[Federal Register: January 3, 2001 (Volume 66, Number 2)]
[Proposed Rules]               
[Page 423-472]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03ja01-29]                         
 

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Part III





Environmental Protection Agency





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40 CFR Parts 413, 433, 438, 463, 464, 467, and 471



Effluent Limitations Guidelines, Pretreatment Standards, and New Source 
Performance Standards for the Metal Products and Machinery Point Source 
Category; Proposed Rule


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 413, 433, 438, 463, 464, 467, and 471

[FRL-6897-6]
RIN 2040-AB79

 
Effluent Limitations Guidelines, Pretreatment Standards, and New 
Source Performance Standards for the Metal Products and Machinery Point 
Source Category; Proposed Rule

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: This proposal represents the Agency's second look at Clean 
Water Act national effluent limitations guidelines and pretreatment 
standards for wastewater discharges from metal products and machinery 
facilities. EPA initially proposed effluent limitations guidelines and 
pretreatment standards for a portion of this category on May 30, 1995 
(60 FR 28210). This proposal completely replaces the 1995 proposal. 
Today's proposed regulation would establish technology-based effluent 
limitations guidelines and pretreatment standards for wastewater 
discharges associated with the operation of new and existing metal 
products and machinery facilities. The metal products and machinery 
industry includes facilities that manufacture, rebuild, or maintain 
metal products, parts, or machines.
    EPA estimates that compliance with this regulation will reduce the 
discharge of conventional pollutants by at least 115 million pounds per 
year, priority pollutants by 12 million pounds per year, and 
nonconventional metal and organic pollutants by 43 million pounds per 
year for an estimated compliance cost of $1.98 billion (pre-tax, 1999$) 
annually. EPA estimates that the annual benefits of the proposal range 
from $0.4 billion to $1.1 billion. In addition, this proposal solicits 
comment on new methodologies for expanding the analysis to include 
additional categories of recreational benefits.

DATES: EPA must receive comments on the proposal by May 3, 2001. EPA is 
conducting a public meeting (9:00 AM--12:00 PM) and hearing on the 
pretreatment standards (1:00 PM--4:00 PM) for this proposed rule on 
each of the following dates: February 6, 2001 in Oakland, CA; February 
13, 2001 in Dallas, TX; and February 22, 2001 in Washington, DC.

ADDRESSES: Submit written comments to, Mr. Michael Ebner, Office of 
Water, Engineering and Analysis Division (4303), U.S. EPA, 1200 
Pennsylvania Ave., NW, Washington, DC 20460 if by mail and to Mr. 
Michael Ebner, U.S. EPA, 401 M St., SW, Room 611 West Tower, 
Washington, DC 20460 if by hand delivery. Comments may also be sent via 
E-mail to ``mpm.comments@epa.gov''. Please submit any references cited 
in your comments. EPA requests an original and three copies of your 
comments and enclosures (including references). Commenters who want EPA 
to acknowledge receipt of their comments should enclose a self-
addressed, stamped envelope. No facsimiles (faxes) will be accepted. 
For additional information on how to submit electronic comments see 
``SUPPLEMENTARY INFORMATION, How to Submit Comments.''
    EPA will be holding public meetings and pretreatment hearings on 
today's proposal on three separate dates. The meeting in Oakland, CA 
will be held at the Oakland Mariott, City Center, 1001 Broadway, 
Oakland, CA 96607. The meeting in Dallas, TX will be held in the 
Oklahoma and Texas rooms at the EPA Region 6 Offices, 1455 Ross Avenue, 
Dallas, TX. The meeting in Washington, DC will be held in EPA's 
Auditorium, Waterside Mall, 401 M St. SW, Washington, DC.
    EPA established the public record for this proposed rulemaking 
under docket number W-99-23. It is located in the Water Docket, East 
Tower Basement, 401 M St. SW, Washington, DC 20460. The record is 
available for inspection from 9 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. For access to the docket materials, call 
(202) 260-3027 to schedule an appointment. You may have to pay a 
reasonable fee for copying.

FOR FURTHER INFORMATION CONTACT: For technical information concerning 
today's proposed rule, contact Mr. Michael Ebner at (202) 260-5397 or 
Ms. Shari Barash at (202) 260-7130. For economic information contact 
Dr. Lynne Tudor at (202) 260-5834.

SUPPLEMENTARY INFORMATION:

Regulated Entities

    Entities potentially regulated by this action include:

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           Category                  Examples of regulated entities
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Industry.....................   Facilities that manufacture,
                                maintain, or rebuild metal parts,
                                products or machines used in the
                                following sectors: Aerospace, Aircraft,
                                Bus & Truck, Electronic Equipment,
                                Hardware, Household Equipment,
                                Instruments, Job Shops, Mobile
                                Industrial Equipment, Motor Vehicles,
                                Office Machines, Ordnance, Precious
                                Metals and Jewelry, Printed Wiring
                                Boards, Railroad, Ships and Boats,
                                Stationary Industrial Equipment, and
                                Miscellaneous Metal Products.
Government...................   State and local government
                                facilities that manufacture, maintain,
                                or rebuild metal parts, products or
                                machines (e.g., a town that operates its
                                own bus, truck, and/or snow removal
                                equipment maintenance facility).
                                Federal facilities that
                                manufacture, maintain, or rebuild metal
                                parts, products or machines (e.g., U.S.
                                Naval Shipyards).
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EPA does not intend the preceding table to be exhaustive, but rather it 
provides a guide for readers regarding entities likely to be regulated 
by this action. This table lists the types of entities that EPA is now 
aware could potentially be regulated by this action. Other types of 
entities not listed in the table could also be regulated. To determine 
whether your facility is regulated by this action, you should carefully 
examine the applicability criteria proposed in Sections III and VI.C 
and detailed further in section 438.1 of the proposed rule. If you have 
questions regarding the applicability of this action to a particular 
entity, consult one of the persons listed for technical information in 
the preceding FOR FURTHER INFORMATION CONTACT section.

How To Submit Comments

    Electronic comments must be identified by the docket number W-99-23 
and must be submitted as an ASCII, or WordPerfect 5/6/7/8/9 or 
Microsoft Word 97 file avoiding the use of special characters and any 
form of encryption. EPA also will accept comments and data on disks in 
Word Perfect 5/6/7/8/9, Microsoft Word 97 or ASCII file format. 
Electronic comments on this notice may be filed online at some Federal 
Depository Libraries. No confidential business information (CBI) should 
be sent via e-mail. In the public record for

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the final MP&M regulation, EPA will respond to comments from the 1995 
Phase I proposal as well as today's proposal. Therefore, comments 
submitted on the Phase I rule do not need to resubmitted in response to 
this proposal.

Public Meeting and Pretreatment Hearing Information:

    In each location, the public meeting will be held in the morning 
and the pretreatment hearing will be held in the afternoon (see DATES 
and ADDRESSES for dates and locations of public meetings and 
pretreatment hearings). During the public meeting, EPA will present 
information on the applicability of the proposed regulation, the 
technology options selected as the basis for the proposed limitations 
and standards, and the compliance costs and pollutant reductions. EPA 
will also allow time for questions and answers during this session. 
During the pretreatment hearing, the public will have the opportunity 
to provide oral comment to EPA. EPA will not address any issues raised 
during the pretreatment hearing at that time, but these comments will 
be recorded and included in the public record for the rule. Persons 
wishing to present formal comments at the public hearing should contact 
Mr. Michael Ebner before the hearing and should have a written copy of 
their comments for submittal.

Protection of Confidential Business Information

    EPA notes that many documents in the record supporting the proposed 
rule have been claimed as CBI and, therefore, EPA has not included 
these documents in the public record. To support the rulemaking, EPA is 
presenting certain information in aggregated form or, alternatively, is 
masking facility identities in order to preserve confidentiality 
claims. Further, the Agency has withheld from disclosure some data not 
claimed as CBI because release of this information could indirectly 
reveal information claimed to be confidential.
    Facility-specific data, claimed as CBI, are available to the 
company that submitted the information. To ensure that EPA protects all 
CBI in accordance with EPA regulations, any requests for company-
specific data should be submitted to EPA on company letterhead and 
signed by the official authorized to receive such data. The request 
must list the specific data requested and include the following 
statement, ``I certify that EPA is authorized to transfer confidential 
business information submitted by my company, and that I am authorized 
to receive it.''

Supporting Documentation

    Several key documents support the proposed regulations:
    1. ``Development Document for the Proposed Effluent Limitations 
Guidelines and Standards for the Metal Products & Machinery Point 
Source Category'' [EPA-821-B-00-005]: This document presents EPA's 
methodology and technical conclusions concerning the Metal Products & 
Machinery Point Source Category.
    2. ``Economic, Environmental, and Benefits Analysis of the Proposed 
Metal Products & Machinery Rule'' [EPA-821-B-00-008]: This document 
presents the methodology employed to assess economic and environmental 
impacts of the proposed rule and the results of the analysis.
    3. Cost-Effectiveness Analysis of the Proposed Effluent Limitations 
Guidelines and Standards for the Metal Products & Machinery Point 
Source Category'' [EPA-821-B-00-007] This document analyzes the cost-
effectiveness of the proposed regulation.
    4. ``Statistical Support Document for the Proposed Effluent 
Limitations Guidelines and Standards for the Metal Products & Machinery 
Industry'' [EPA-821-B-00-006]: This document establishes the 
statistical methodology for developing numerical discharge limitations.
    Major supporting documents are available in hard copy from the 
National Service Center for Environmental Publications (NSCEP), U.S. 
EPA/NSCEP, P.O. Box 42419, Cincinnati, Ohio, USA 45242-2419, (800) 490-
9198, http://www.epa.gov/ncepihom/. You can obtain electronic copies of 
this preamble and rule as well as the technical and economic support 
documents for today's proposal at http://www.epa.gov/ost/guide/mpm.

Overview

    The preamble describes the terms, acronyms, and abbreviations used 
in this notice; the background documents that support these proposed 
regulations; the legal authority of these rules; a summary of the 
proposal; background information; and the technical and economic 
methodologies used by the Agency to develop these regulations. This 
preamble also solicits comment and data on specific areas of interest.
    In addition, this preamble proposes to update references in the 
relevant parts of the Code of Federal Regulations (CFR) to include the 
Metal Products & Machinery Point Source Category. References in 40 CFR 
would be updated in the Electroplating (part 413), Metal Finishing 
(part 433), Plastic Molding and Forming (part 463), Metal Molding and 
Casting (part 464), Aluminum Forming (467), and Nonferrous Metals 
Forming and Metal Powders (part 471) effluent guidelines point source 
categories.

Table of Contents

I. Legal Authority
II. Background
    A. Statutory Authorities
    B. Existing Regulation for Metals Industries
    C. 1995 Proposal for Phase I Sectors
    D. Summary of Most Significant Changes from 1995 Proposal
III. Scope of Proposal
IV. Industry Description
V. Summary of Data Collection Activities
    A. Existing Data Sources
    B. Survey Questionnaires
    C. Wastewater Sampling and Site Visits
    D. Industry Submitted Data
    E. Summary of Public Participation
VI. Industry Subcategorization
    A. Methodology and Factors Considered for Basis of 
Subcategorization
    B. Proposed Subcategories
    C. General Description of Facilities in Each Subcategory
VII. Water Use and Wastewater Characteristics
    A. Wastewater Sources and Characteristics
    B. Pollution Prevention, Recycle, Reuse, and Water Conservation 
Practices
VIII. Development of Effluent Limitations Guidelines and Standards
    A. Overview of Technology Options
    B. Determination of Long-Term Averages, Variability Factors, and 
Limitations
IX. Best Practicable Control Technology Currently Available (BPT)
    A. General Metals Subcategory
    B. Metal Finishing Job Shops Subcategory
    C. Non-Chromium Anodizing Subcategory
    D. Printed Wiring Board Subcategory
    E. Steel Forming & Finishing Subcategory
    F. Oily Wastes Subcategory
    G. Railroad Line Maintenance Subcategory
    H. Shipbuilding Dry Dock Subcategory
X. Best Conventional Pollutant Control Technology (BCT)
    A. July 9, 1986 BCT Methodology
    B. Discussion of BCT Option for Metal-Bearing Wastewater
    C. Discussion of BCT Option for Oily Wastewater
XI. Best Available Technology Economically Achievable (BAT)
    A. General Metals Subcategory
    B. Metal Finishing Job Shops Subcategory
    C. Non-Chromium Anodizing Subcategory
    D. Printed Wiring Board Subcategory
    E. Steel Forming & Finishing Subcategory
    F. Oily Wastes Subcategory
    G. Railroad Line Maintenance Subcategory
    H. Shipbuilding Dry Dock Subcategory
XII. Pretreatment Standards for Existing Sources (PSES)
    A. Need for Pretreatment Standards
    B. Overview of Technology Options for PSES
    C. Overview of Low Flow Exclusions
    D. General Metals Subcategory

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    E. Metal Finishing Job Shops Subcategory
    F. Non-Chromium Anodizing Subcategory
    G. Printed Wiring Board Subcategory
    H. Steel Forming & Finishing Subcategory
    I. Oily Wastes Subcategory
    J. Railroad Line Maintenance Subcategory
    K. Shipbuilding Dry Dock Subcategory
XIII. New Source Performance Standards (NSPS) and Pretreatment 
Standards for New Sources (PSNS)
    A. NSPS for the General Metals Subcategory
    B. PSNS for the General Metals Subcategory
    C. NSPS for the Metal Finishing Job Shops Subcategory
    D. PSNS for the Metal Finishing Job Shops Subcategory
    E. NSPS for the Non-Chromium Anodizing Subcategory
    F. PSNS for the Non-Chromium Anodizing Subcategory
    G. NSPS for the Printed Wiring Board Subcategory
    H. PSNS for the Printed Wiring Board Subcategory
    I. NSPS for the Steel Forming and Finishing Subcategory
    J. PSNS for the Steel Forming and Finishing Subcategory
    K. NSPS for the Oily Wastes Subcategory
    L. PSNS for the Oily Wastes Subcategory
    M. NSPS for the Railroad Line Maintenance Subcategory
    N. PSNS for the Railroad Line Maintenance Subcategory
    O. NSPS for the Shipbuilding Dry Dock Subcategory
    P. PSNS for the Shipbuilding Dry Dock Subcategory
XIV. Issues Related to the Methodology Used to Determine POTW 
Performance
    A. Assessment of Acceptable POTWs
    B. Assessment of Acceptable Data
    C. Assessment of Removals When Effluent Is Below the Analytical 
Method Minimum Level
XV. Methodology for Estimating Costs & Pollutant Reductions
XVI. Economic Impact and Social Cost Analysis
    A. Introduction
    B. Facility Level Impacts
    C. Firm Level Impacts
    D. Impacts on Governments
    E. Community Level Impacts
    F. Foreign Trade Impacts
    G. Impacts on New Facilities
    H. Social Costs
XVII. Cost Effectiveness Analysis
    A. Methodology
    B. Cost-Effectiveness Analysis for Indirect Dischargers
    C. Cost-Effectiveness Analysis for Direct Dischargers
XVIII. Non-Water Quality Environmental Impacts
    A. Air Pollution
    B. Solid Waste
    C. Energy Requirements
XIX. Water Quality, Sewage Sludge, and Other Environmental Impacts
    A. Introduction
    B. Beneficial Impacts of the MP&M Proposed Rule
XX. Benefit Analysis
    A. Overview of Benefits
    B. Reduced Human Health Risk
    C. Ecological, Recreational, and Nonuser Benefits
    D. Productivity Changes: Cleaner Sewage Sludge (Biosolids)
    E. Total Estimated Benefits of the Proposed MP&M Rule
    F. Benefit-Cost Comparison
XXI. Regulatory Implementation
    A. Compliance Dates
    B. Implementation of Limitations and Standards
    C. Monitoring Flexibility
    D. Pollution Prevention Alternative for the Metal Finishing Job 
Shops Subcategory
    E. Upset and Bypass Provisions
    F. Variances and Modifications
    G. Relationship of Effluent Limitations and Pretreatment 
Standards to NPDES Permits and Local Limits
    H. Best Management Practices
XXII. Related Acts of Congress, Executive Orders, and Agency 
Initiatives
    A. Paperwork Reduction Act
    B. Unfunded Mandates Reform Act (UMRA)
    C. Regulatory Flexibility Act (RFA) as Amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA)
    D. Executive Order 12866: Regulatory Planning and Review
    E. Executive Order 13132: Federalism
    F. Executive Order 12898: Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
    G. Executive Order 13045: Protection of Children from 
Environmental Health Risks and Safety Risks
    H. Executive Order 13084: Consultation and Coordination With 
Indian Tribal Governments
    I. National Technology Transfer and Advancement Act
    J. Plain Language Directive
    K. Executive Order 13158: Marine Protected Areas
    L. Coastal Zone Act Reauthorization Amendments (CZARA)
XXIII. Solicitation of Data and Comments
XXIV. Guidelines for Submission of Analytical Data
    A. Types of Data Requested
    B. Analytes Requested
    C. Quality Assurance/ Quality Control (QA/QC) Requirements
Appendix A to the Preamble:Abbreviations, Acronyms, and Other Terms 
Used in This Document.

I. Legal Authority

    EPA is proposing this regulation under the authorities of sections 
301, 304, 306, 307, 308, 402 and 501 of the Clean Water Act, 33 U.S.C. 
Sections 1311, 1314, 1316, 1317, 1318, 1342 and 1361 and under 
authority of the Pollution Prevention Act of 1990 (PPA), 42 U.S.C. 
13101 et seq., Pub L. 101-508, November 5, 1990.

II. Background

A. Statutory Authorities

1. Clean Water Act
    Congress adopted the Clean Water Act (CWA) to ``restore and 
maintain the chemical, physical, and biological integrity of the 
nation's waters'' (Section 101(a), 33 U.S.C. 1251(a)). To achieve this 
goal, the CWA prohibits the discharge of pollutants into navigable 
waters except in compliance with the statute. The CWA confronts the 
problem of water pollution on a number of different fronts. Its primary 
reliance, however, is on establishing restrictions on the types and 
amounts of pollutants discharged from various industrial, commercial, 
and public sources of wastewater.
    Congress recognized that regulating only those sources that 
discharge effluent directly into the nation's waters would not be 
sufficient to achieve the CWA's goals. Consequently, the CWA requires 
EPA to promulgate nationally applicable pretreatment standards which 
restrict pollutant discharges for those who discharge wastewater 
indirectly through sewers flowing to publicly-owned treatment works 
(POTWs) (Sections 307(b) and (c), 33 U.S.C. 1317(b) and (c)). EPA 
establishes national pretreatment standards for those pollutants in 
wastewater from indirect dischargers which may pass through or 
interfere with POTW operations. Generally, the Agency develops 
pretreatment standards to ensure that wastewater from direct and 
indirect industrial dischargers are subject to similar levels of 
treatment. In addition, EPA requires POTWs to implement local treatment 
limits applicable to their industrial indirect dischargers to satisfy 
any local requirements (40 CFR 403.5).
    Direct dischargers must comply with effluent limitations in 
National Pollutant Discharge Elimination System (``NPDES'') permits; 
indirect dischargers must comply with pretreatment standards. EPA 
establishes these limitations and standards by regulation for 
categories of industrial dischargers and bases them on the degree of 
control that can be achieved using various levels of pollution control 
technology.
a. Best Practicable Control Technology Currently Available (BPT)--Sec. 
304(b)(1) of the CWA
    In the guidelines for an industry category, EPA defines BPT 
effluent limits for conventional, toxic,\1\ and non-

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conventional pollutants. In specifying BPT, EPA looks at a number of 
factors. EPA first considers the cost of achieving effluent reductions 
in relation to the effluent reduction benefits. The Agency also 
considers the age of the equipment and facilities, the processes 
employed and any required process changes, engineering aspects of the 
control technologies, non-water quality environmental impacts 
(including energy requirements), and such other factors as the Agency 
deems appropriate (CWA 304(b)(1)(B)). Traditionally, EPA establishes 
BPT effluent limitations based on the average of the best performances 
of facilities within the industry of various ages, sizes, processes or 
other common characteristics. Where existing performance is uniformly 
inadequate, EPA may require higher levels of control than currently in 
place in an industrial category if the Agency determines that the 
technology can be practically applied.
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    \1\ In the initial stages of EPA CWA regulation, EPA efforts 
emphasized the achievement of BPT limitations for control of the 
``classical'' pollutants (e.g., TSS, pH, BOD5). However, 
nothing on the face of the statute explicitly restricted BPT 
limitation to such pollutants. Following passage of the Clean Water 
Act of 1977 with its requirement for point sources to achieve best 
available technology limitations to control discharges of toxic 
pollutants, EPA shifted its focus to address the listed priority 
toxic pollutants under the guidelines program. BPT guidelines 
continue to include limitations to address all pollutants.
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b. Best Available Technology Economically Achievable (BAT)--Sec. 
304(b)(2) of the CWA
    In general, BAT effluent limitations guidelines represent the best 
existing economically achievable performance of direct discharging 
plants in the industrial subcategory or category. The factors 
considered in assessing BAT include the cost of achieving BAT effluent 
reductions, the age of equipment and facilities involved, the processes 
employed, engineering aspects of the control technology, potential 
process changes, non-water quality environmental impacts (including 
energy requirements), and such factors as the Administrator deems 
appropriate. The Agency retains considerable discretion in assigning 
the weight to be accorded to these factors. An additional statutory 
factor considered in setting BAT is economic achievability. Generally, 
EPA determines the economic achievability on the basis of the total 
cost to the industrial subcategory and the overall effect of the rule 
on the industry's financial health. The Agency may base BAT limitations 
upon effluent reductions attainable through changes in a facility's 
processes and operations. As with BPT, where existing performance is 
uniformly inadequate, EPA may base BAT upon technology transferred from 
a different subcategory within an industry or from another industrial 
category. In addition, the Agency may base BAT upon process changes or 
internal controls, even when these technologies are not common industry 
practice.
c. Best Conventional Pollutant Control Technology (BCT)--Sec. 304(b)(4) 
of the CWA
    The 1977 amendments to the CWA required EPA to identify effluent 
reduction levels for conventional pollutants associated with BCT 
technology for discharges from existing industrial point sources. BCT 
is not an additional limitation, but replaces Best Available Technology 
(BAT) for control of conventional pollutants. In addition to other 
factors specified in Section 304(b)(4)(B), the CWA requires that EPA 
establish BCT limitations after consideration of a two-part ``cost-
reasonableness'' test. EPA explained its methodology for the 
development of BCT limitations in July 1986 (51 FR 24974).
    Section 304(a)(4) designates the following as conventional 
pollutants: biochemical oxygen demand (BOD5), total 
suspended solids (TSS), fecal coliform, pH, and any additional 
pollutants defined by the Administrator as conventional. The 
Administrator designated oil and grease as an additional conventional 
pollutant on July 30, 1979 (44 FR 44501).
d. New Source Performance Standards (NSPS)--Sec. 306 of the CWA
    NSPS reflect effluent reductions that are achievable based on the 
best available demonstrated control technology. New facilities have the 
opportunity to install the best and most efficient production processes 
and wastewater treatment technologies. As a result, NSPS should 
represent the greatest degree of effluent reduction attainable through 
the application of the best available demonstrated control technology 
for all pollutants (i.e., conventional, non-conventional, and priority 
pollutants). In establishing NSPS, the CWA directs EPA to take into 
consideration the cost of achieving the effluent reduction and any non-
water quality environmental impacts and energy requirements.
e. Pretreatment Standards for Existing Sources (PSES)--Sec. 307(b) of 
the CWA
    PSES are designed to prevent the discharge of pollutants that pass 
through, interfere with, or are otherwise incompatible with the 
operation of publicly owned treatment works (POTWs). The CWA authorizes 
EPA to establish pretreatment standards for pollutants that pass 
through POTWs or interfere with treatment processes or sludge disposal 
methods at POTWs. Pretreatment standards are technology-based and 
analogous to BAT effluent limitations guidelines.
    The General Pretreatment Regulations, which set forth the framework 
for implementing categorical pretreatment standards, are found at 40 
CFR part 403. Those regulations contain a definition of pass through 
that addresses localized rather than national instances of pass through 
and establish pretreatment standards that apply to all non-domestic 
dischargers. See 52 FR 1586, January 14, 1987.
f. Pretreatment Standards for New Sources (PSNS)--Sec. 307(b) of the 
CWA
    Like PSES, PSNS are designed to prevent the discharges of 
pollutants that pass through, interfere with, or are otherwise 
incompatible with the operation of POTWs. New indirect dischargers have 
the opportunity to incorporate into their plants the best available 
demonstrated technologies. The Agency considers the same factors in 
promulgating PSNS as it considers in promulgating NSPS.
2. Pollution Prevention Act
    The Pollution Prevention Act of 1990 (PPA) (42 U.S.C. 13101 et 
seq., Pub. L. 101-508, November 5, 1990) makes pollution prevention the 
national policy of the United States. The PPA identifies an 
environmental management hierarchy in which pollution ``should be 
prevented or reduced whenever feasible; pollution that cannot be 
prevented should be recycled in an environmentally safe manner, 
whenever feasible; pollution that cannot be prevented or recycled 
should be treated in an environmentally safe manner whenever feasible; 
and disposal or release into the environment should be employed only as 
a last resort* * *'' (42 U.S.C. 13103). In short, preventing pollution 
before it is created is preferable to trying to manage, treat or 
dispose of it after it is created. According to the PPA, source 
reduction reduces the generation and release of hazardous substances, 
pollutants, wastes, contaminants or residuals at the source, usually 
within a process. The term source reduction ``* * * includes equipment 
or technology modifications, process or procedure modifications, 
reformulation or redesign of products, substitution of raw materials, 
and improvements in housekeeping, maintenance, training, or inventory

[[Page 428]]

control. The term `source reduction' does not include any practice 
which alters the physical, chemical, or biological characteristics or 
the volume of a hazardous substance, pollutant, or contaminant through 
a process or activity which itself is not integral to or necessary for 
the production of a product or the providing of a service.'' In effect, 
source reduction means reducing the amount of a pollutant that enters a 
waste stream or that is otherwise released into the environment prior 
to out-of-process recycling, treatment, or disposal.

B. Existing Regulation for Metals Industries

    EPA has established effluent guidelines regulations for thirteen 
industrial categories which may perform operations that are sometimes 
found in MP&M facilities. These effluent guidelines are:
     Electroplating (40 CFR part 413);
     Iron and Steel Manufacturing (40 CFR part 420);
     Nonferrous Metals Manufacturing (40 CFR part 421);
     Ferroalloy Manufacturing (40 CFR part 424);
     Metal Finishing (40 CFR part 433);
     Battery Manufacturing (40 CFR part 461);
     Metal Molding & Casting (40 CFR part 464);
     Coil Coating (40 CFR part 465);
     Porcelain Enameling (40 CFR part 466);
     Aluminum Forming (40 CFR part 467);
     Copper Forming (40 CFR part 468);
     Electrical and Electronic Components (40 CFR part 469); 
and
     Nonferrous Metals Forming and Metal Powders (40 CFR part 
471).
    In 1986, the Agency reviewed coverage of these regulations and 
identified a significant number of metals processing facilities 
discharging wastewater that these 13 regulations did not cover. Based 
on this review, EPA performed a more detailed analysis of these 
facilities that were not subject to national effluent guidelines and 
pretreatment standards. This analysis identified the discharge of 
significant amounts of pollutants. This analysis resulted in the 
decision to develop national limitations and standards for the 
``Machinery Manufacturing and Rebuilding'' (MM&R) point source 
category. In 1992, EPA changed the name of the category to ``Metal 
Products and Machinery'' (MP&M) to clarify coverage of the category (57 
FR 19748).
    EPA recognizes that in some cases unit operations performed in 
industries covered by the existing effluent guidelines are the same as 
unit operations performed at MP&M facilities. In general, when unit 
operations and their associated wastewater discharges are already 
covered by an existing effluent guideline, they will remain covered 
under that effluent guideline. (See Sec. 438.1(b)). However, for the 
existing Electroplating (40 CFR 413) and Metal Finishing (40 CFR 433) 
effluent guidelines some facilities will be covered by this proposal. 
EPA is proposing to replace the existing Electroplating (40 CFR 413) 
and Metal Finishing (40 CFR 433) effluent guidelines with the MP&M 
regulations for all facilities in the Printed Wiring Board subcategory 
(see proposed rule Sec. 438.40) and the Metal Finishing Job Shops 
subcategory (see proposed rule Sec. 438.20). (See Table II.B-1 for 
clarification for details and Section VI.C for a discussion of 
subcategory-specific applicability).
    When a facility covered by an existing metals effluent guidelines 
(other than Electroplating or Metal Finishing) discharges wastewater 
from unit operations not covered under that existing metals guideline 
but covered under MP&M, the facility will need to comply with both 
regulations. (See Sec. 438.1(c)). In those cases, the permit writer or 
control authority (e.g., Publicly Owned Treatment Works) will combine 
the limitations using an approach that proportions the limitations 
based on the different in-scope production levels (for production-based 
standards) or wastewater flows. POTWs refer to this approach as the 
``combined wastestream formula'' (40 CFR 403.6(e)), while NPDES permit 
writers refer to it as the ``building block approach.'' Permit writers 
and local control authorities currently issue permits and control 
mechanisms for many facilities in other effluent guidelines categories 
where overlaps with more than one effluent limitation guidelines 
regulation occur (e.g., Organic Chemicals, Plastics, and Synthetic 
Fibers; Pesticide Manufacturing; Pesticide Formulating, Packaging and 
Repackaging; and Pharmaceutical Manufacturing). See Sections III and 
VI.C of this preamble for additional discussion of applicability.

                          Table II.B-1.--Clarification of Coverage by MP&M Subcategory
----------------------------------------------------------------------------------------------------------------
                                                                 Proposing to continue      Proposing to cover
                                      Proposing to continue to   to cover under 40 CFR    under  40 CFR Part 438
             Subcategory               cover under 40 CFR Part      Part 433  (Metal        (Metal Products &
                                        413  (Electroplating)          Finishing)               Machinery)
----------------------------------------------------------------------------------------------------------------
General Metals......................  Existing facilities that  Existing facilities      All new and existing
                                       are currently covered     that are currently       direct dischargers in
                                       by 413 AND are indirect   covered (or new          this subcategory
                                       dischargers that          facilities that would    regardless of annual
                                       introduce less than or    be covered) by 433 AND   wastewater discharge
                                       equal to 1 million        are indirect             volume and all new and
                                       gallons per year into a   dischargers that         existing indirect
                                       POTW.                     introduce less than or   dischargers in this
                                                                 equal to 1 million       subcategory with
                                                                 gallons per year into    annual wastewater
                                                                 a POTW.                  discharges greater
                                                                                          than 1 million gallons
                                                                                          per year.(See Sec.
                                                                                          438.10).
Metal Finishing Job Shops...........  none (see non-chromium    none (see non-chromium   All new and existing
                                       anodizing).               anodizing).              direct and indirect
                                                                                          discharges under this
                                                                                          subcategory. These
                                                                                          facilities would no
                                                                                          longer be covered by
                                                                                          413 or 433. (See Sec.
                                                                                          438.20).

[[Page 429]]


Non-Chromium Anodizers..............  Existing indirect         New and existing         Existing and new direct
Note: Facilities that perform          dischargers that are      indirect dischargers     dischargers that only
 anodizing with chromium or with the   currently covered by      (not covered by 413)     perform non-chromium
 use of dichromate sealants (or        413 AND that only         that only perform non-   anodizing (or do not
 commingle their non-chromium          perform non-chromium      chromium anodizing (or   commingle their non-
 anodizing process wastewater with     anodizing (or do not      do not commingle their   chromium anodizing
 wastewaster from other MP&M           commingle their non-      non-chromium anodizing   wastewater with other
 subcategories) will be covered by     chromium anodizing        wastewater with other    process wastewater for
 40 CFR 438.                           wastewater with other     process wastewater for   discharge). (See Sec.
                                       process wastewater for    discharge).              438.30).
                                       discharge).

Printed Wiring Board (Printed         None....................  None...................  All new and existing
 Circuit Board).                                                                          direct and indirect
                                                                                          dischargers under this
                                                                                          subcategory. These
                                                                                          facilities would no
                                                                                          longer be covered by
                                                                                          413 or 433. (See Sec.
                                                                                          438.40).
Steel Forming & Finishing...........  N/A.....................  N/A....................  All new and existing
                                                                                          direct and indirect
                                                                                          discharges under this
                                                                                          subcategory as
                                                                                          described. (See Sec.
                                                                                          438.50).
Oily Waste..........................  N/A.....................  N/A....................  All new and existing
                                                                                          direct and indirect
                                                                                          dischargers under this
                                                                                          subcategory as
                                                                                          described. (See Sec.
                                                                                          438.60) (This
                                                                                          subcategory excludes
                                                                                          new and existing
                                                                                          indirect dischargers
                                                                                          that introduce less
                                                                                          than or equal to 2 MGY
                                                                                          into a POTW.
                                                                                          Facilities under the
                                                                                          cutoff are not and
                                                                                          will not be covered by
                                                                                          national categorical
                                                                                          regulations).
Railroad Line Maintenance...........  N/A.....................  N/A....................  All new and existing
                                                                                          direct dischargers
                                                                                          under this subcategory
                                                                                          as described. (See
                                                                                          Sec.  438.70) There
                                                                                          are no national
                                                                                          categorical
                                                                                          pretreatment standards
                                                                                          for these facilities.
Shipbuilding Dry Docks..............  N/A.....................  N/A....................  All new and existing
                                                                                          direct dischargers
                                                                                          under this subcategory
                                                                                          as described. (See
                                                                                          Sec.  438.80) There
                                                                                          are no national
                                                                                          categorical
                                                                                          pretreatment standards
                                                                                          for these facilities.
----------------------------------------------------------------------------------------------------------------

EPA does not intend the preceding table to be exhaustive, but rather it 
provides a guide for readers regarding the clarification of the 
proposed applicability to the Electroplating, Metal Finishing, and 
Metal Products & Machinery effluent guidelines. In order to determine 
whether EPA is proposing to regulate a particular facility by this 
action, please carefully examine the applicability criteria detailed in 
the codified text of this proposed rule accompanying today's preamble.

C. 1995 Proposal for Phase I Sectors

    On May 30, 1995, EPA published a proposal entitled, ``Effluent 
Limitations Guidelines, Pretreatment Standards, and New Source 
Performance Standards: Metal Products and Machinery'' (60 FR 28210). 
Throughout this preamble, EPA refers to this 1995 proposal as the 
``Phase I'' or the ``1995'' proposal for the Metal Products and 
Machinery industry. EPA initially divided the industry into two phases 
based on industrial sector as the Agency believed that would make the 
regulation more manageable. The Phase I proposal included the following 
industry sectors: Aerospace; Aircraft; Electronic Equipment; Hardware; 
Mobile Industrial Equipment; Ordnance; and Stationary Industrial 
Equipment. At that time, EPA planned to propose a rule for the Phase II 
sectors approximately three years after the MP&M Phase I proposal.
    EPA received over 4,000 pages of public comment on the Phase I 
proposal. One area where commenters from all stakeholder groups (i.e, 
industry, environmental groups, regulators) were in agreement was that 
EPA should not divide the industry into two separate regulations. 
Commenters raised concerns regarding the regulation of similar 
facilities with different compliance schedules and potentially 
different limitations solely based on whether they were in a Phase I or 
Phase II MP&M industrial sector. Furthermore, many facilities performed 
work in multiple sectors. In such cases, permit writers and control 
authorities (e.g., POTWs) would need to decide which MP&M rule (Phase I 
or II) applied to a facility.
    Based on these comments, EPA decided to combine the two phases of 
the regulation into one proposal--today's proposal. Today's proposal 
will completely replace the 1995 proposal. Under the 304(m) decree as 
amended, these MP&M rules are to be promulgated in December 2002. EPA 
developed today's proposal using data from both the Phase I and II data 
collection efforts. (See Section V for discussion on MP&M data 
collection efforts). In the public

[[Page 430]]

record for the final MP&M regulation, EPA will respond to comments from 
the 1995 Phase I proposal as well as today's proposal. Therefore, 
comments submitted on the Phase I rule do not need to be resubmitted in 
response to this proposal. In addition, compliance deadlines proposed 
in the 1995 Phase I proposal would obviously no longer apply.

D. Summary of Most Significant Changes from 1995 Proposal

    In addition to the merging of the Phase I and Phase II industry 
sectors under one proposed rule, as discussed in Section II.C. above, 
there were several areas of comments from the 1995 proposal that EPA 
attempted to address in today's proposed rule.
Use of Aluminum and Iron as Indicator Parameters
    In the 1995 proposal, EPA proposed pretreatment standards for 
existing sources (PSES) for seven metals and cyanide as well as oil & 
grease. Aluminum and iron were two of the seven metals with numerical 
pretreatment standards. As discussed in the Phase I preamble (60 FR 
28228), EPA intended to regulate aluminum and iron as indicator metals 
for removal of non-regulated metals that may be processed at MP&M 
sites. Due to the fact that the optimal pH levels for the removal of 
aluminum (pH = 7.5-8) and iron (pH = 10.5) represent the end points of 
the pH range for the removal of most metals that EPA expected to be in 
MP&M wastewater, the Agency concluded that the removal of aluminum and 
iron would indicate effective removal of other metal types. EPA 
received many comments from various stakeholder groups, including 
Publicly Owned Treatment Works (POTWs) on this issue. The comments from 
POTWs indicated that in addition to MP&M sites using aluminum and iron 
as treatment chemicals, POTWs also use coagulants and flocculation aids 
containing these metals for treatment. Many POTWs considered it 
desirable to receive discharges containing aluminum and iron as it may 
reduce their treatment chemical costs. Therefore, EPA has decided not 
to propose pretreatment standards for aluminum and iron from indirect 
discharging MP&M facilities in today's combined MP&M proposal. However, 
EPA is proposing aluminum limitations for facilities in one subcategory 
(i.e., Non-Chromium Anodizing) that discharge directly into the 
nation's surface waters (see Section VI for a discussion on 
subcategorization).
Use of Oil and Grease as an Indicator Parameter
    EPA also received many comments on the Phase I proposal regarding 
regulation of another pollutant, oil & grease (O&G), as an indicator 
parameter. In an effort to reduce the burden of analytical monitoring 
for organic pollutants on the Phase I MP&M facilities, EPA chose to 
propose the use of O&G as an indicator parameter for organic 
pollutants. EPA proposed a limit (daily maximum of 35 mg/L and a 
monthly average of 17 mg/L) that demonstrated good removals of organic 
pollutants in MP&M wastewater. As discussed in the preamble of the 1995 
proposal (60 FR 28231), EPA identified several organic pollutants (2-
methylnapthalene, 2-propanone, n-octadecane, and n-tetradecane) that 
would ``pass through'' a POTW (see Section XII for a discussion of POTW 
pass through). EPA stated that ``these organic pollutants are more 
likely to partition to the oily phase than the water phase, thus EPA 
believed that the treatment and removal of oil and grease in wastewater 
will also result in significant removals of these pollutants.'' Many 
commenters stated that the pretreatment standard proposed for O&G was 
too stringent. They commented that EPA typically does not establish 
pretreatment standards for conventional pollutants such as O&G and that 
local POTWs are in the best position to establish standards for O&G, 
where necessary, taking into account POTW design and current O&G 
loading and that the typical local limits for O&G are between 100-200 
mg/L.
    Based on these comments, EPA expanded its wastewater sampling and 
analysis program to include a variety of potential organic pollutant 
indicators. EPA investigated the correlation of organic pollutant 
concentrations and removals at MP&M sites with the following 
parameters: Oil & Grease (as Hexane Extractable Material (HEM)), Total 
Organic Carbon (TOC), Chemical Oxygen Demand (COD), 5-Day Biochemical 
Oxygen Demand (BOD5), Total Petroleum Hydrocarbon (as Silica 
Gel Treated-Hexane Extractable Material (SGT-HEM)), and Total 
Recoverable Phenolics. EPA determined TOC to be the best correlation 
for removal of organic pollutants from MP&M wastewater.
    To determine which parameter best indicated the amount of organic 
pollutants in an MP&M wastestream, EPA researched the analytical 
methods for each parameter to determine what organic constituents the 
method measures, how the method measures them, and the limitations of 
the method. Because sampling at MP&M facilities generally lasted five 
days, EPA did not have enough data available to statistically establish 
a correlation on a site level. Therefore, EPA grouped all of the data 
from EPA sampling at MP&M facilities into the following organic-
pollutant-bearing wastestream categories that fed sampled treatment 
systems: machining and grinding, washing and maintenance, wastewater 
expected to have low concentrations of organic compounds, and oily 
wastewater from shipbuilding dry docks. The Agency chose to group the 
wastestreams in this manner in order to determine if a particular 
organic indicator parameter was more appropriate for different types of 
wastewater. That is, machining and grinding wastewater tended to have 
more concentrated organic constituents while wastewater from washing 
and maintenance was more dilute. EPA also identified other unit 
operations (apart from washing and maintenance) that resulted in 
wastewater with low concentrations of organic constituents. And, EPA 
chose to analyze wastewater from shipbuilding dry docks separately 
because of the type of treatment in place. Shipbuilding dry docks tend 
to treat their wastewater with dissolved air flotation (DAF); 
therefore, the Agency analyzed the data from these facilities in order 
to determine the best organic indicator parameter for these treatment 
systems.
    For each wastewater type and its associated wastewater treatment 
system, EPA characterized the composition of organic pollutants in all 
of the influent samples, in all of the effluent samples, and the total 
samples (influent, effluent, and intermediate sampling points) 
associated with the treatment system. EPA studied the correlation of 
the concentration of each indicator parameter noted above to the sum of 
the concentrations of the organic pollutants by calculating the Pearson 
and Spearman Rank correlation coefficients and comparing the 
coefficients of each parameter against each other. Additionally, EPA 
compared the general removal of the sum of organic pollutant compounds 
with the removal of each indicator parameter (see the Technical 
Development Document for a detailed discussion of these analyses).
    EPA determined TOC to be the best overall indicator parameter for 
the evaluated MP&M wastestreams because this analysis measures all 
types of organic compounds. Total recoverable phenolics, O&G (as HEM), 
Total Petroleum Hydrocarbons (as SGT-HEM), and BOD5 analyses 
only measure

[[Page 431]]

specific organic components so they would not measure all possible 
organic compounds in an effluent stream.
    In addition to expanding its sampling program, EPA considered a 
variety of approaches to address the comments on the use of O&G as an 
indicator for organic pollutants. EPA considered the use of a Total 
Organics list or an organics management plan (similar to the Total 
Toxic Organics (TTO) list and solvent management plan used in the Metal 
Finishing effluent guidelines (40 CFR 433)) as well as allowing 
facilities to choose from a list of possible indicator pollutants 
(where they would demonstrate a correlation to their wastewater) or to 
choose to monitor for the specific organic pollutants themselves. EPA 
shared these ideas with small entity representatives during the SBREFA 
process (see Section XXII.C for a discussion on the SBREFA process) and 
with stakeholders during various public meetings and industry 
conferences. (See Section V.E for a discussion on EPA's public outreach 
efforts).
    EPA has decided to propose three alternatives to allow for maximum 
flexibility while ensuring reductions in the amount of organic 
pollutants discharged from MP&M facilities. EPA is proposing to require 
MP&M facilities within the scope of this rule to either: (1) Meet a 
numerical limit for the total sum of a list of specific organic 
pollutants (similar to the TTO parameter used in the Metal Finishing 
effluent guidelines); (2) meet a numerical limit for the specified 
indicator parameter; or (3) develop and certify the implementation of 
an organics management plan. (See Section XXI.C.2 for a discussion on 
regulatory implementation and proposed monitoring flexibility).
Variability of MP&M Process Wastewater Discharges
    EPA also revised its analytical wastewater sampling program to 
address two other issues raised by commenters in response to the 1995 
proposal. First, commenters stated that EPA's analytical data did not 
accurately reflect the variability in the wastewater flow and pollutant 
concentration experienced over time at MP&M sites. More specifically, 
metal finishing and electroplating job shops stated that EPA did not 
account for the variability of the metal types and products processed 
at their facilities; and therefore, EPA's proposed numerical limits did 
not accurately reflect pollutant concentrations achievable by these 
types of facilities (see Section VI.C.2. for a description of metal 
finishing job shops). EPA has addressed this by performing specific 
sampling targeted to assess the wastewater variability at metal 
finishing and electroplating job shops. EPA sampled raw wastewater from 
a variety of unit operations as well as wastewater treatment systems at 
three job shops for five days each. After a period of a few months, the 
Agency then returned to each facility a second and/or a third time for 
three days of analytical wastewater sampling. In addition, when 
determining proposed limits for the Metal Finishing Job Shops 
subcategory, EPA, when possible, only used data collected from metal 
finishing and electroplating facilities. However, EPA had to transfer 
data from the General Metals subcategory for several pollutants that 
are being proposed in the Metal Finishing Job Shops subcategory. Based 
on this approach, the limits for facilities in the Metal Finishing Job 
Shop subcategory include increased variability factors as compared to 
the General Metals subcategory (i.e., the subcategory that EPA 
considers to be the most similar in terms of raw wastewater 
characterization).
    Second, commenters stated the variability factors that EPA used in 
the development of limitations were relatively small. Commenters 
expressed their view that EPA's variability factors did not reflect the 
variations in raw wastewater pollutant concentrations nor the 
variations in the effectiveness of treatment technologies (particularly 
in the case of cyanide). Section VIII.B of today's preamble discusses 
the statistical methodology used for developing variability factors. In 
an effort to ensure that the variability factors represent the 
variability found in MP&M wastewater, EPA performed 44 sampling 
episodes during post-1995 proposal data collection in addition to the 
27 sampling episodes performed during the Phase I data collection 
effort. EPA also specifically included sampling of 20 cyanide 
destruction systems.
    In addition, the Agency has collected long-term effluent data from 
facility Compliance Reports and Discharge Monitoring Reports in an 
effort to perform a ``real world'' check on the achievability of 
today's proposed limits. This data is available for review in the 
public record for today's proposal (see Section 6.6.1 of the public 
record). Indirect dischargers file compliance monitoring reports with 
their control authority (e.g., POTW) at least twice per year as 
required under the General Pretreatment Standards (40 CFR part 403) 
while direct discharges file discharge monitoring reports with their 
permitting authority at least once per year. The Agency received these 
reports from 14 well-operated BAT facilities whose analytical data EPA 
used in establishing limitations. EPA sent letters to nine facilities 
requesting this data. In addition, five sites provided EPA with this 
data during site visits or sampling episodes or as part of their 
questionnaire response. Because this data is not in a form that allows 
direct use for calculating limits or for comparison to the proposed 
limits, EPA was not able to use this data in setting or evaluating the 
compliance aspects of the limits and standards in today's proposal. 
However, following proposal, EPA will reformat and evaluate this long-
term effluent monitoring data in relation to the proposed limits. In 
cases where EPA finds a facility in its costing database that was used 
to set the numerical limits and is not in compliance with the proposed 
pollutant limitations, EPA will reassess the achievability of these 
limits by a well-operated BAT system. When a system is not achieving 
the proposed limits consistently it may be because either the system is 
not achieving the projected long-term average (LTA) or the system has 
higher variability than EPA determined using its standard methodology. 
EPA requests comment on its methodology for determining LTAs and 
variability factors. In cases where EPA determines that improved system 
operation will allow the limits to be consistently achieved it will 
include additional treatment costs for the facility in its cost 
estimations for the final rule where EPA has not already done so. EPA 
concludes, in following the approach described above, that it will 
address the concerns of commenters on the Phase I proposed rule related 
to the achievability of the numerical limits by well operated and 
economically achievable treatment systems. EPA requests comment on this 
method of performing a ``real world'' check on the achievability of its 
proposed limits.
    Finally, as compared to the 1995 proposed limits, today's proposed 
numerical limits for total cyanide have increased almost one order of 
magnitude from 0.03 mg/L for the daily maximum and 0.02 for the monthly 
average to 0.21 and 0.12, respectively. This increase is largely due to 
increased variability factors.
Low Discharge Flow Exclusion
    Another significant change from the 1995 proposal is EPA's proposed 
low wastewater discharge flow exclusion (``low flow cutoff'') for 
indirect dischargers. In the 1995 proposed rule, EPA set a low flow 
cutoff at one million gallons per year (1 MGY) for all indirect

[[Page 432]]

discharging facilities included in the Phase I sectors. This meant that 
EPA proposed to exclude, from the MP&M pretreatment standards, 
facilities discharging less than 1 MGY to a POTW. The Agency included 
the low flow cutoff to reduce the potentially large burden on POTWs 
related to issuing permits or other control mechanisms to thousands of 
the smallest MP&M Phase I sector facilities. EPA received many comments 
on the level of the proposed flow cutoff. Based on these comments and 
the recommendations of the SBREFA panel (see Section XXII.C on the 
SBREFA process), EPA analyzed a range of flow cutoffs for indirect 
dischargers ranging from no flow cutoff to 6.25 million gallons per 
year. EPA notes that at 6.25 million gallons per year, the General 
Pretreatment Standards (40 CFR part 403) classify indirect discharging 
facilities as ``Significant Industrial Users'' (SIUs). Under the 
General Pretreatment Standards, control authorities (e.g., POTWs) must 
issue permits or other control mechanisms to SIUs and, therefore, no 
POTW burden reductions are realized above a flow cutoff of 6.25 MGY. 
(However, there may be some minimal increase in burden for modifying 
permits or control mechanisms).
    EPA estimates that there are a total of 89,000 facilities within 
the scope of the proposed rule. Many of these facilities are small 
facilities and may be contributing minimal pollutant loadings to the 
environment. A low flow exclusion allows regulatory authorities to 
focus attention on those facilities with significant discharges. This 
may also improve the cost-effectiveness of the rule. In developing 
today's proposal, EPA considered POTW burden, costs, pollutant 
removals, and economic impacts of the various flow cutoffs.
    Unlike the 1995 proposal, EPA is now proposing to subcategorize 
(i.e., subdivide) the MP&M category (see Section VI of this preamble 
for a discussion on subcategorization of the industry). Therefore, EPA 
has analyzed the various low flow cutoffs by subcategory, noting in 
particular which subcategories are not currently covered under existing 
pretreatment standards. When existing pretreatment standards already 
cover all facilities in a particular subcategory, POTWs will not be 
relieved of their administrative burden, regardless of whether or not a 
low flow exclusion exists in the MP&M pretreatment standards. But other 
factors, such as a disproportionate economic impact have been 
considered.
    The combination of subcategorization of the industry, current 
coverage under existing pretreatment standards, and analysis of a range 
of low flow cutoffs has led EPA to propose different levels for the low 
flow exclusion for indirect dischargers in various subcategories. For 
example, EPA is proposing the 1 MGY cutoff for indirect dischargers in 
the General Metals subcategory, but is proposing no flow cutoff for 
indirect dischargers in the Printed Wiring Board subcategory (see 
Section VI.C. for descriptions of the proposed subcategories). This 
difference is partially due to the fact that under the Electroplating 
and Metal Finishing pretreatment standards (40 CFR parts 413 and 433), 
EPA already regulates (thus it already requires POTWs to issue control 
mechanisms for) all indirect discharging facilities in the proposed 
Printed Wiring Board subcategory (approximately 620 facilities). In 
addition, EPA does not project any severe or moderate economic impacts 
for the small estimated number of printed wiring board facilities (52) 
that would be eligible for a low flow cutoff of 1 MGY. In contrast, EPA 
has not previously established pretreatment standards for approximately 
75 percent of the indirect discharging facilities in the proposed 
General Metals subcategory (approximately 26,000 total facilities). 
Approximately 23,000 indirect dischargers in the proposed General 
Metals Subcategory discharge less than 1 MGY. If EPA did not exclude 
these facilities, the number of permit issuances that POTWs are 
responsible for would increase significantly. There are approximately 
30,000 industrial users currently covered nationally by existing 
pretreatment standards for all effluent guidelines. Low flow exclusions 
being proposed for the General Metals and Oily Wastes subcategories, 
POTWs (or other control authorities) would have to issue an additional 
51,000 permits/control mechanisms. EPA discusses further the rationale 
for proposing a low flow cutoff exclusion for certain subcategories in 
Section XII.
Mass-Based v. Concentration-Based Limits
    EPA also received many comments on the issue of mass-based versus 
concentration-based limits. In the 1995 proposal, EPA proposed 
concentration-based limits with the requirement that control 
authorities (e.g., POTWs) implement them as mass-based limits. EPA 
notes that under the NPDES permit program, the Agency already requires 
permit writers to implement effluent limitations guidelines as mass-
based limits whenever feasible (40 CFR 122.45(f)). EPA proposed 
requiring this conversion to mass-based limits because the Agency 
believed that it was necessary to ensure the use of water conservation 
and pollution prevention practices similar to those that were part of 
EPA's selected option (60 FR 28230). EPA expected permit writers and 
control authorities to use historical flow as a basis for the 
conversion to mass-based limits for facilities that demonstrated good 
water conservation practices. However, for facilities that did not have 
good water conservation in place, EPA provided detailed guidance to 
permit writers and control authorities in the Technical Development 
Document (TDD) for the 1995 proposal. The TDD included information on a 
full range of water use levels (in gallons/sq.ft.) for a large variety 
of MP&M operations as well as guidance on how permit writers and 
control authorities could determine if a facility was using good water 
conservation practices.
    EPA received comments on the administrative burden on POTWs 
associated with implementation of mass-based limits. The commenters 
stated that the burden was largely due to the fact that most MP&M 
facilities do not collect production information on a wastestream-by-
wastestream basis. POTWs have continued to voice these concerns at 
recent public stakeholder meetings. To address this issue, EPA 
collected additional MP&M unit operation-specific information on 
pollution prevention practices, water use, and wastewater generation in 
the data collection efforts that followed the Phase I proposal.
    In today's proposal, EPA is again proposing concentration-based 
limits (for all but one subcategory) and is providing detailed 
information on water use levels for specific unit operations in the 
Technical Development Document. However, the Agency is no longer 
proposing to require control authorities (e.g., POTWs) or permit 
writers to implement the limits on a mass basis. Instead EPA is 
proposing to authorize control authorities and permit writers to decide 
when it is most appropriate to implement mass-based limits. EPA 
believes that this approach will reduce implementation burden on POTWs 
and will result in increased use of water conservation practices at the 
facilities where POTWs and permit writers think it is most needed. EPA 
believes that MP&M facilities that use the best pollution prevention 
and water conservation practices may request that the control authority 
or permit writer use mass-based limits in their permits or other 
control mechanisms. (See Section XXI.B for a discussion on regulatory 
implementation).

[[Page 433]]

III. Scope of Proposal

    Today's proposed effluent guideline applies to process wastewater 
discharges from existing or new industrial sites engaged in 
manufacturing, rebuilding, or maintenance of metal parts, products or 
machines to be used in one of the following industrial sectors:
     Aerospace;
     Aircraft;
     Bus and Truck;
     Electronic Equipment;
     Hardware;
     Household Equipment;
     Instruments;
     Job Shops;
     Mobile Industrial Equipment;
     Motor Vehicle;
     Office Machine;
     Ordnance;
     Precious Metals and Jewelry;
     Printed Wiring Boards;
     Railroad;
     Ships and Boats;
     Stationary Industrial Equipment; and
     Miscellaneous Metal Products.
    EPA has identified these eighteen industrial sectors in the MP&M 
category; these sectors manufacture, maintain and rebuild metal 
products under more than 200 different SIC codes. See Appendix A of 
today's proposed rule for a description of typical products within 
these eighteen MP&M industrial sectors. Although EPA is using these 18 
industrial sectors to generally describe the scope of today's proposal, 
the Agency notes that it is not using these industrial sectors to 
subcategorize (or subdivide) the regulations for the industry. EPA's 
analysis to date suggests that the industrial sectors do not correlate 
well with the types of waste generated, and many facilities perform 
operations covered by multiple sectors. Instead, EPA is proposing to 
define subcategories based on unit operations performed and the nature 
of the waste generated (see Section VI of today's notice for a 
discussions on subcategorization and subcategory-specific 
applicability).
    EPA does not intend to include maintenance or repair of metal 
parts, products, or machines that occur only as ancillary activities at 
facilities that it did not include in the 18 industrial sectors. (See 
Sec. 438.1(d)). EPA believes that these ancillary repair and 
maintenance activities would typically generate only small quantities 
of wastewater. In most cases, these periodic repair and maintenance 
activities at facilities not in one of the 18 industrial sectors would 
comprise only a very small portion of the total wastewater flow at the 
facility. The Agency believes local limits will be adequate to address 
these discharges for indirect dischargers and that permit writers can 
establish limits using Best Professional Judgement (BPJ) to regulate 
these ancillary waste streams for direct dischargers. Permit writers 
should consult the effluent limitations guidelines and standards for 
the primary category of such a facility (See 40 CFR Chapter I, 
Subchapter N for all existing effluent limitations guidelines and 
standards). As an example, EPA does not intend for the MP&M proposal to 
include process wastewater discharges from an on-site machine or 
maintenance shop at a facility engaged in the manufacture of organic 
chemicals when the facility operates that shop to maintain the 
equipment related to manufacturing their products (i.e., organic 
chemicals). As discussed above, these wastewaters can be regulated 
through local limits or through BPJ using the Organic Chemicals, 
Plastics, and Synthetic Fibers (OCPSF) regulations. Alternatively, 
since aircraft is an in-scope MP&M industrial sector, EPA is proposing 
to include process wastewater discharges from activities related to 
maintaining or repairing aircraft or other related (metal) equipment 
(e.g., deicing vehicles) at airports.
    EPA also intends to cover wastewater from MP&M operations related 
to maintenance and repair of metal products, parts, and machinery at 
military installations. For example, this proposal includes wastewater 
generated from the maintenance and repair of aircraft, cars, trucks, 
buses, tanks (or other armor personnel carriers), and industrial 
equipment--all of which are commonly performed at military 
installations.
    Today's proposal only covers process wastewater generated at MP&M 
facilities. EPA is not covering non-process wastewater which includes 
sanitary wastewater, non-contact cooling water, and storm water. EPA 
has characterized typical MP&M unit operations as belonging to one or 
more of the following types: Assembly/disassembly; metal deposition; 
metal shaping; organic deposition; printed wiring board; surface 
finishing; surface preparation; and dry dock operations. Typical unit 
operations at MP&M facilities include any one or more of the following: 
abrasive blasting, abrasive jet machining, acid treatment, adhesive 
bonding, alkaline cleaning for removal of oil, alkaline treatment, 
anodizing, aqueous degreasing, assembly, barrel finishing, brazing, 
burnishing, calibration, chemical conversion coating, chemical milling, 
chromate conversion coating, corrosion preventive coating, disassembly, 
electrical discharge machining, electrochemical machining, electroless 
plating, electrolytic cleaning, electroplating, electron beam 
machining, electropolishing, floor cleaning, grinding, heat treating, 
hot-dip coating, impact deformation, laminating, laser beam machining, 
machining, metal spraying, painting (spray/brush or immersion), photo 
resist applications, physical vapor deposition, plating, plasma arc 
machining, polishing, pressure deformation, rinsing, salt bath 
descaling, soldering, solvent degreasing, sputtering, stripping (paint 
or metallic coating), testing, thermal cutting, thermal infusion, 
ultrasonic machining, vacuum metalizing, washing finished product, 
welding, wet air pollution control, and numerous sub-operations within 
those listed above. EPA notes that not all MP&M unit operations 
generate process wastewater. In addition, many of these operations 
frequently have associated rinses that remove materials that preceding 
processes deposit on the surface of the workpiece and water-discharging 
air pollution control devices which become contaminated with process 
contaminants removed from the air. EPA is including both of these 
wastewater flows under the scope of today's proposed regulation. (See 
Sec. 438.2(e)).
    The Agency is also including under today's proposed regulation 
wastewater discharges from non-contact, nondestructive testing 
performed at MP&M facilities. (See Sec. 438.2(e)). A common source of 
``nondestructive testing'' wastewater is photographic waste from 
nondestructive X-ray examination of parts. The Agency is proposing to 
cover this wastewater because of the potential concentration of silver 
in the wastewater discharge.
    EPA is not covering wastewater generated from electroplating-type 
operations during semiconductor wafer manufacturing or wafer 
fabrication processes (i.e., tape automated bonding--``TAB'' and 
controlled collapse chip connection--``C-4'') occurring in a ``clean 
room'' environment because it believes that these operations are much 
different than the other electroplating operations that EPA is covering 
by these guidelines and do not contribute significant amounts of 
pollutants to the wastewater discharge. (See Sec. 438.1(e)). The new 
and emerging technologies involved in semiconductor wafer fabrication 
add microscopic amounts of metal (usually copper) to only selective 
portions of the wafer to

[[Page 434]]

enhance circuitry and decrease wafer size. Other electroplating 
operations that EPA is proposing to cover under this guideline 
generally occur on a larger scale and produce a more concentrated 
metal-bearing wastewater. Moreover, the wafer fabrication processes 
occur in a clean room with a highly-controlled atmosphere and using 
highly-purified materials and specialized tools that are much different 
from typical metal-finishing equipment. These specialized tools and 
conditions enable the manufacturer to add microscopic levels (less than 
one micron) of metal to only one side of the wafer, in contrast to the 
non-selective, macroscopic (micron to micron-inch) plating used in 
common metal finishing. Therefore, EPA is proposing not to cover 
wastewater from wafer fabrication processes under this rule. However, 
in today's proposal the Agency is covering wastewater generated from 
electroplating during semiconductor final wafer assembly. (See 
Sec. 438.1(e)).
    EPA is proposing to cover wastewater generated from washing 
vehicles only when it occurs as a preparatory step prior to performing 
an MP&M unit operation (e.g., prior to disassembly to perform engine 
maintenance or rebuilding). (See Sec. 438.1(f)). MP&M facilities may 
perform these preparatory washes to remove oils, dirt and grit prior to 
performing the maintenance or repair operations and as a result the 
combined wastewater contains significant amounts of oil and grease 
along with total suspended solids. However, this proposed regulation 
does not cover the washing of cars, aircraft or other vehicles when it 
is performed only for aesthetic/cosmetic purposes because EPA does not 
expect these washes to contain significant concentrations of 
pollutants. (See Sec. 438.1(f)).
    EPA is also proposing to cover wastewater generated from unit 
operations performed by drum reconditioners/refurbishers to prepare 
drums for reuse. (See Sec. 438.1(a)). These facilities perform 
operations on metal drums such as chaining, caustic washing, acid 
cleaning, acid etching, impact deformation, leak testing, corrosion 
inhibition, shot blasting, and painting. The Agency considers 
facilities that perform these operations as part of the Stationary 
Industrial Equipment sector. However, the Agency notes that it is 
currently considering the development of an effluent guideline for the 
drum reconditioning industry. If EPA develops regulations for this new 
industrial category, it is possible that the Agency would cover these 
facilities under that rule and not under the MP&M regulation. EPA 
solicits comment on whether these facilities would be more 
appropriately covered under the MP&M rule or under a new industrial 
category for drum reconditioners.
    EPA did not collect information with respect to MP&M operations at 
gasoline service stations (SIC code 5541), passenger car rental 
facilities (SIC code 7514), or utility trailer and recreational vehicle 
rental facilities (SIC code 7519); therefore, this proposed regulation 
does not cover process wastewater generated by maintenance and repair 
activities when they occur at gasoline stations or car rental 
facilities. (See Sec. 438.1(g)). As discussed in Sections VI.C and XII 
of this notice, EPA is proposing to exclude facilities in the General 
Metals and Oily Waste subcategories that discharge MP&M process 
wastewater below a specified flow rate (one and two million gallons per 
year, respectively). EPA expects that many facilities that only perform 
repair and maintenance activities (e.g., auto repair shops, light 
aircraft maintenance) will be excluded as most will fit into the 
applicability of either the General Metals or Oily Waste subcategories 
and have process wastewater discharges below the subcategory-specific 
flow cutoffs.
    EPA is proposing to cover MP&M process wastewater at mixed-use 
facilities (i.e., any municipal, private, U.S. military or federal 
facility which contains both industrial and commercial/administrative 
buildings at which one or more industrial sites conduct operations 
within the facility's boundaries). (See Sec. 438.1(h)). However, unlike 
the typical industrial facility, such as an aircraft or electronic 
equipment manufacturing plant with one primary manufacturing activity, 
the majority of military installations are mixed-use facilities and are 
more like municipalities with several small industries as well as other 
operations within their boundaries. Many of these installations also 
include a variety of tenant activities, including contractor and other 
Department of Defense federal agency activities. At these mixed-use 
facilities, EPA is proposing to cover wastewater from manufacturing, 
maintenance and repair activities performed on metal parts, products or 
machines (e.g. maintenance and repair of vehicles and aircraft). (See 
Sec. 438.1(h)). EPA concluded that these types of operations will 
generate wastewater containing either high metals content or high oil 
and grease, or both. EPA is not proposing to cover wastewater from 
other non-metal repair, maintenance or manufacturing operations at 
mixed-use facilities such as wastewater from residential housing, 
schools, churches, recreational parks, shopping centers, gas stations, 
utility plants, and hospitals. The Agency believes that wastewater 
generated from these activities will not contain the same types and 
concentrations of pollutants (such as metals and oil and grease) as 
wastewater from MP&M operations. Finally, the geographic size of many 
military installations (for example, over 300 square miles at Fort 
Hood, TX and over 1.1 million acres at the China Lake Naval Air Warfare 
Center, CA) makes it difficult to treat them as a single facility. 
Therefore, EPA is proposing to allow wastewater generated at different 
sites (individual buildings as well as outdoor locations where 
manufacturing, rebuilding, or maintenance occur on metal parts, 
products, or machines) within a mixed-use facility to be dealt with as 
separate discharges for the purpose of applying the appropriate low 
flow cutoff (when applicable). EPA is proposing to allow the control 
authority to use its discretion in determining which wastewater 
discharges can be considered separate discharges for the purposes of 
applying the appropriate low flow cutoff (when applicable). The 
determination would likely be based on the degree of proximity between 
industrial operations and a practical application of the requirements 
for applicable MP&M subcategories. Control authorities (and permit 
writers) will have to determine when it is appropriate to apply 
standards for more than one subcategory to a mixed-use facility and 
when to use the combined waste stream formula (or building block 
approach). For example, a military installation that generates 
wastewater from vehicle maintenance operations that is treated in a 
separate wastewater system than wastewater generated from its metal 
finishing operations could be covered by both the Oily Wastes 
subcategory for its vehicle maintenance operations and by the General 
Metals subcategory for it surface finishing operations. (See Section VI 
for a discussion of subcategorization and subcategory-specific 
applicability).
    EPA seeks information from other facilities that believe they would 
fall within this mixed-use facility category. In addition, EPA seeks 
comments on the choice to allow control authorities to make a 
determination concerning applying the low flow cutoffs to separate 
discharges and the factors for making such a decision as well as 
alternative ways to divide a mixed-use facility.
    See Section II.B for a discussion on the applicability of today's 
proposed rule with respect to the thirteen existing

[[Page 435]]

metals-related effluent limitations guidelines and standards 
regulations.

IV. Industry Description

    As described in Section III, the MP&M industry is comprised of 
facilities that manufacture, rebuild, or maintain metal parts, products 
or machines to be used in one of 18 industrial sectors. Based on 
results of the MP&M survey database, there are an estimated 89,000 MP&M 
sites. Based on detailed survey results, an estimated 63,000 MP&M sites 
discharge process water. Of the facilities discharging process 
wastewater, EPA estimates that 93 percent are indirect dischargers and 
7 percent are direct dischargers. The Agency estimates that there are 
approximately 26,000 facilities that fall into one of three zero 
discharge categories: zero discharge, non-water-using, or contract 
haulers.
    MP&M water-discharging sites range in size from less than 10 
employees to sites with tens of thousands of employees and from 
wastewater discharge flow rates of less than 100 gallons per year to 
wastewater discharge flow rates exceeding 100 million gallons per year. 
Of water discharging facilities, approximately 98 percent of MP&M sites 
have 500 or fewer employees and approximately 78 percent of MP&M sites 
have 100 or fewer employees. EPA estimates that facilities with less 
than 100 employees discharge approximately 11 percent of the total 
annual wastewater discharged by the MP&M industry and that facilities 
having between 100 and 500 employees discharge approximately 50% of the 
industry total flow. Facilities with greater than 500 employees 
discharge 39 percent of the industry total.
    MP&M facilities are located throughout the United States. The 
Agency received survey data from every EPA region and 48 separate 
states. EPA estimates that the largest concentrations of MP&M 
facilities are located in EPA Regions III (MD, PA, VA, WV), V (IL, IN, 
MI, MN, OH, WI), and IX (AZ, CA, HI). In addition EPA estimates the 
seven states with the largest concentrations of MP&M facilities are: 
California (25 percent), Pennsylvania (23 percent), Virginia (11 
percent), Ohio (5 percent), Colorado (4 percent), Texas (3 percent), 
and Indiana (2 percent).
    EPA estimates that approximately 3 percent of the industry (water 
dischargers and zero dischargers) generates annual revenues less than 
$100,000, approximately 41 percent generate annual revenues between 
$100,000 and $500,000, approximately 5 percent generate annual revenues 
between $500,000 and $1,500,000, and approximately 33 percent generate 
over $5,000,000 annual revenues. The Agency notes that facilities with 
annual revenues greater than $5,000,000 discharge approximately 73 
percent of the total wastewater discharged by the industry.
    Although facilities in the MP&M industry produce a wide range of 
products, the operations performed can be described by two types of 
activities: manufacturing, and rebuilding/maintenance. Manufacturing is 
the series of unit operations necessary to produce metal products, and 
is generally performed in a production environment. Rebuilding/
maintenance is the series of unit operations necessary to disassemble 
used metal products into components, replace the components or 
subassemblies or restore them to original function, and reassemble the 
metal product. These operations are intended to keep metal products in 
operating condition and can be performed in either a production or a 
non-production environment.
    Table IV-1, below, summarizes the estimated number of MP&M sites 
(water dischargers and zero dischargers) and total discharge flow 
(prior to implementation of the proposed rule) by activity or activity 
combination. The largest number of sites, approximately 44,000, perform 
``rebuilding/maintenance only'' and account for approximately 9 percent 
of the total estimated discharge flow for the industry. ``Manufacturing 
only'' represents the next largest number of facilities (27,000) and 
represents the largest percentage of the total estimated discharge flow 
for the industry (75.2 percent).

                   Table IV-1.--MP&M Sites * and Total Discharge Flow by Activity Combination
----------------------------------------------------------------------------------------------------------------
                                                     Estimated         Total
                                                     number of       estimated     Percentage of   Percentage of
                    Activity                           water      discharge flow    total water        total
                                                    discharging    (million gal/    discharging   discharge flow
                                                    MP&M sites          yr)         MP&M sites
----------------------------------------------------------------------------------------------------------------
Manufacturing, Rebuilding/Maintenance...........           7,400          11,200             8.3             9.1
Manufacturing Only..............................          27,000          91,700            30.4            75.2
Rebuilding/Maintenance Only.....................          44,000          11,100            49.5             9.1
Unknown/others..................................          10,500           8,100            11.8             6.6
                                                 ---------------------------------------------------------------
    Total **....................................          89,000         122,000           100.0          100.0
----------------------------------------------------------------------------------------------------------------
* This table includes all MP&M sites, for a presentation of this distribution for water discharging sites only,
  see the Technical Development Document for today's proposal.
** Totals may not add due to rounding.

    Of the 26,000 sites that achieve zero discharge of process 
wastewater, many use but do not discharge process water. Based on 
information from the MP&M Detailed Surveys, site visits, and technical 
literature (see Section V for a discussion of the data collection 
activities), these sites achieve zero discharge of process wastewater 
in one or more of the following ways:
     Sites contract haul for off-site disposal all process 
wastewater generated on site;
     Sites discharge process wastewater to either on-site 
septic systems or deep-well injection systems;
     Sites perform end-of-pipe treatment and reuse all process 
wastewater generated on site;
     Sites perform either in-process or end-of-pipe evaporation 
to eliminate wastewater discharges; or
     Sites perform in-process recirculation and recycling to 
eliminate wastewater discharges.
    EPA's Underground Injection Control (UIC) Program, authorized by 
the Safe Drinking Water Act, regulates shallow on-site systems and deep 
wells that discharge fluids or wastewater into the subsurface and thus 
may endanger underground sources of drinking water.
    If a facility disposes any wastewater (other than solely sanitary 
waste) into a shallow disposal system (e.g., septic system or a floor 
drain connected to a dry well) that well is covered by the UIC program. 
If you think you have a UIC

[[Page 436]]

disposal well on your facility, you should contact your State UIC 
Program authority to determine your compliance status.
    EPA published the Class V Rule in the Federal Register on December 
7, 1999 (64 FR 68545), which affected facilities using on site systems 
to dispose waste associated with motor vehicle service and repair in 
state-designated groundwater protection areas. The EPA is scheduled to 
develop additional requirements for other Class V wells that receive 
endangering waste. Contact your State UIC Program for more information 
on these developing regulations.

V. Summary of Data Collection Activities

A. Existing Data Sources

    While developing today's proposal, EPA reviewed data from other 
metals industry effluent guidelines, the National Risk Management 
Research Laboratory (NRMRL) treatability database, the 50 POTW Study, 
the Domestic Sewage Study, and the Toxics Release Inventory (TRI).
    For the MP&M technology effectiveness assessment effort, EPA 
reviewed sampling data collected to characterize treatment systems for 
the development of effluent guidelines for other metals industries (see 
Section II.B for a discussion on other metals industry effluent 
guidelines). For several previous effluent guidelines, EPA used 
treatment data from metals industries to develop the Combined Metals 
Database (CMDB), which served as the basis for developing limits for 
these industries. EPA also developed a separate database used as the 
basis for limits for the Metal Finishing category. EPA used the CMDB 
and Metal Finishing data as a guide in identifying well-designed and 
well-operated MP&M treatment systems. EPA did not use these data in 
developing the MP&M technology effectiveness concentrations, since the 
Agency collected sufficient data from MP&M sites to develop technology 
effectiveness concentrations.
    EPA also reviewed the Technical Development Documents (TDDs), 
sampling episode reports, and supporting record materials for the other 
metals industries' rulemakings to identify available data. EPA used 
these data for the preliminary assessment of the MP&M industry, but did 
not use these data for estimating MP&M pollutant loadings because EPA 
obtained sufficient data for the MP&M sampling program to characterize 
the MP&M unit operations.
    EPA's National Risk Management Research Laboratory (NRMRL) 
developed a treatability database (formerly called the Risk Reduction 
Engineering Laboratory (RREL) database) to provide data on the removal 
and destruction of chemicals in various types of media, including 
water, soil, debris, sludge, and sediment. This database contains 
treatability data from POTWs and industrial facilities for various 
pollutants. The database includes physical and chemical data for each 
pollutant, the types of treatment used to treat the specific 
pollutants, the types of wastewater treated, the size of the POTW or 
industrial site, and the treatment concentrations achieved. EPA used 
this database as one means to assess removal of MP&M pollutants of 
concern by POTWs.
    In September 1982, EPA published the Fate of Priority Pollutants in 
Publicly Owned Treatment Works, referred to as the 50 POTW Study. The 
purpose of this study was to generate, compile, and report data on the 
occurrence and fate of the 129 priority pollutants in 50 POTWs. The 
report presents all of the data collected, the results of preliminary 
evaluations of these data, and the results of calculations to determine 
the quantity of priority pollutants in the influent to POTWs; 
discharged from the POTWs; in the effluent from intermediate process 
streams; and in the POTW sludge streams. EPA used the data from this 
study as one means to assess removal by POTWs of MP&M pollutants of 
concern (see Section XII.A for additional discussion on the use of the 
50 POTW Study).
    In February 1986, EPA issued the ``Report to Congress on the 
Discharge of Hazardous Wastes to Publicly Owned Treatment Works'', 
referred to as the Domestic Sewage Study (DSS). This report, which was 
based in part on the 50 POTW Study, revealed a significant number of 
sites discharging pollutants to POTWs, which are a threat to the 
treatment capability of the POTW. These pollutants were not regulated 
by national categorical pretreatment standards at that time. EPA used 
the information in the DSS in developing the Preliminary Data Summary 
(PDS) for the MP&M category (October 1989).
    The Toxics Release Inventory (TRI) database contains specific toxic 
chemical release and transfer information from manufacturing facilities 
throughout the United States. EPA considered using the TRI database in 
developing the MP&M effluent guidelines. However, EPA did not use TRI 
data on wastewater discharges from MP&M sites because sufficient data 
were not available for effluent guidelines development. For example, in 
developing the MP&M effluent guidelines, EPA uses wastewater influent 
concentrations to characterize a facility's wastewater and to calculate 
treatment efficiency (i.e., percent removal across the treatment 
system). TRI does not provide concentrations for the influent to a 
facility's treatment system. EPA also did not use the data on 
wastewater discharge because many MP&M sites do not meet the reporting 
thresholds for the TRI database.

B. Survey Questionnaires

    As discussed in Section II.C, EPA originally intended to propose 
the MP&M rulemaking in two phases. Therefore, EPA's data collection 
efforts, particularly the use of survey questionnaires, was handled in 
two phases to collect data from the relevant industrial sectors. EPA 
distributed two screener and six detailed questionnaires (surveys) 
between 1989 and 1996. For a list of surveys by distribution date, see 
the Technical Development Document for today's proposed rule.
1. Screener Surveys
    EPA developed and distributed two screener surveys. In 1990, EPA 
distributed 8,342 screener surveys to sites believed to be engaged in 
the original seven Phase I MP&M sectors. In 1996, EPA distributed 5,325 
screener surveys to sites believed to be engaged in the eleven Phase II 
MP&M sectors. The purpose of the screener surveys was to identify sites 
to receive the more detailed follow-up surveys and to make a 
preliminary assessment of the MP&M industry.
    In each case, EPA identified the SIC codes applicable to the 
respective MP&M sectors and then calculated the number of sites to 
receive the screener within each SIC code by a coefficient of variation 
(CV) minimization procedure (see the respective Database Summary 
Reports for the screener surveys in the public record for a detailed 
discussion of the CV procedure). Based on the number of sites selected 
within each SIC code, the Agency purchased a list of randomly selected 
names and addresses from Dun & Bradstreet. This list included twice the 
number of sites specified by the CV minimization procedure for each SIC 
code. Dun & Bradstreet randomly selected the requested number of sites 
from the Dun & Bradstreet database for each SIC code. From this list of 
potential recipient sites, the Agency randomly selected sites to 
receive the screener surveys. For a more detailed discussion on the 
screener surveys, see the Technical

[[Page 437]]

Development Document for today's proposed rule.
    EPA also sent the 1996 screener survey to 1,750 randomly selected 
sites in Ohio for the purpose of collecting information for an 
environmental benefits study. (See Section XX.F or the Economic, 
Environmental, and Benefits Analysis for today's proposed rule for a 
detailed discussion of EPA's Ohio Benefits Case Study).
2. Industrial Detailed Surveys
    Based on responses to the 1990 screener, EPA sent a more detailed 
survey to a select group of water-using MP&M sites. The Agency designed 
this survey to collect detailed technical and financial information. 
EPA selected 1,020 detailed survey recipients from the following three 
groups of sites:
     Water-discharging 1989 screener respondents (860 sites);
     Water-using 1989 screener respondents that did not 
discharge process water (74 sites); and
     Water-discharging sites from well-known MP&M companies 
that did not receive the 1989 screener (86 sites).
    EPA used information from the first two groups of survey recipients 
to develop pollutant loadings and reductions and to develop compliance 
cost estimates. Because EPA did not randomly select the third group of 
recipients, EPA did not use the data to develop national estimates.
    In an effort to reduce burden on survey recipients for the second 
phase of the data collection effort, EPA developed two similar detailed 
surveys. Based on the development of the 1995 MP&M proposal, EPA chose 
to collect more detailed information from sites with annual process 
wastewater discharges greater than one million gallons per year (1 
MGY). EPA sent the ``long'' detailed survey to all 353 1996 screener 
respondents who indicated they discharged one million or more gallons 
of MP&M process wastewater annually and performed MP&M operations. The 
Agency sent the ``short'' detailed survey to 101 randomly selected 1996 
screener respondents who indicated they discharged less than one 
million gallons of MP&M process wastewater annually and performed MP&M 
operations.
    The detailed surveys collected information to identify the site 
location and contact person, number of employees, facility age, process 
wastewater discharge status and destination, and wastewater discharge 
permits and permitting authority as well as general information about 
metal types processed, MP&M products and production levels, water use 
for unit operations, and wastewater discharge from unit operations. EPA 
used the process information to evaluate water use and discharge 
practices and sources of pollutants for each MP&M unit operation. EPA 
also requested detailed information on MP&M wet unit operations, 
pollution prevention practices, wastewater treatment technologies, 
costs for water use and wastewater treatment systems, and wastewater/
sludge disposal costs. EPA also requested each site to provide block 
diagrams of the production process and the wastewater treatment system. 
The unit operation information included: metal types processed, 
production rate, operating schedule, chemical additives, volume and 
destination of process wastewater and rinse waters, in-process 
pollution prevention technologies, and in-process flow control 
technologies. The information EPA requested for each wastewater 
treatment unit included: operating flow rate, design capacity, 
operating time, chemical additives, and unit operations discharging to 
each treatment unit. In addition, EPA asked each site to provide the 
type of MP&M wastewater sampling data collected. EPA used these data to 
characterize the industry, to perform subcategorization analyses, to 
identify best management practices, to evaluate performance of the 
treatment technology for inclusion in the regulatory options, and to 
develop regulatory compliance cost estimates.
    EPA also collected detailed financial and economic information 
about the site or the company owning the site. In addition, the 1996 
long detailed questionnaire included a section that requested 
supplemental information on other MP&M facilities owned by the company. 
EPA included this voluntary section to measure the combined impact of 
proposed MP&M effluent guidelines on companies with multiple MP&M 
facilities that discharge process wastewater. This section requested 
the same information collected in the 1996 MP&M screener survey. 
Responses to questions in this section provided the size, industrial 
sector, revenue, unit operations, and water usage of the company's 
other MP&M facilities.
    The 1996 short survey included the identical general site and 
process information and economic information collected in the long 
detailed survey. However, to minimize the burden on facilities 
discharging less than one million gallons of process wastewater, EPA 
did not require these facilities to provide the detailed information on 
MP&M unit operations or treatment technologies that the Agency 
requested in the long survey. For a question-by-question comparison of 
the short and long 1996 detailed surveys, see the Technical Development 
Document for today's proposed rule.
    Finally, EPA developed a detailed survey, under a separate 
rulemaking effort, to collect detailed information from facilities that 
are currently covered by the Iron and Steel Manufacturing effluent 
guidelines. Following field sampling of iron and steel sites and review 
of the completed industry surveys, EPA decided that some iron and steel 
operations would be more appropriately covered by the MP&M rule because 
they were more like MP&M operations (see Section VI.C.5 for a 
discussion on the Steel Forming & Finishing subcategory). Based on 
EPA's decision regarding these operations, the Agency coded and entered 
process information from 47 iron and steel surveys into the MP&M 
costing input database.
3. Municipality Survey
    EPA distributed the municipality surveys in 1996 to city and county 
facilities that might operate MP&M facilities. The Agency designed this 
survey to measure the impact of this rule on municipalities and other 
government entities that perform maintenance and rebuilding operations 
on MP&M products (e.g., bus and truck, automobiles).
    The Agency sent the municipality survey to 150 city and county 
facilities randomly selected from the Municipality Year Book-1995 based 
on population and geographic location. EPA allocated sixty percent of 
the sample to municipalities and 40 percent to counties. The 60/40 
distribution was approximately proportional to their aggregate 
populations in the frame. EPA divided the municipality sample and the 
county sample into three size groupings as measured by population. For 
municipalities, the population groupings were: less than 10,000 
residents, 10,000-50,000 residents, and 50,000 or more residents. For 
counties, the population groupings were: less than 50,000 residents, 
50,000-150,000 residents, and 150,000 or more residents. The geographic 
stratification conformed to the Census definitions of Northeast, North 
Central, South, Pacific, and Mountain states. The technical questions 
in the Municipality Survey were basically identical to the 1996 short 
detailed survey; however, EPA adapted the financial and economic 
questions so that they were appropriate for these facilities.

[[Page 438]]

4. Federal Facilities Survey
    In April 1998, EPA distributed the federal facilities detailed 
survey to the following federal agencies:
     Department of Energy;
     Department of Defense;
     National Aeronautics and Space Administration (NASA);
     Department of Transportation (including the United States 
Coast Guard);
     Department of the Interior;
     Department of Agriculture; and
     United States Postal Service.
EPA designed this survey to assess the impact of the MP&M effluent 
limitations guidelines and standards on federal agencies that operate 
MP&M facilities. EPA distributed the survey to federal agencies likely 
to perform industrial operations on metal products or machines. The 
Agency requested that the representatives of the seven listed federal 
agencies voluntarily distribute copies of the survey to sites they 
believed performed MP&M operations. The information collected in the 
1996 federal survey was identical to the long survey. After engineering 
review and coding, EPA entered data from 44 federal surveys into the 
database. Because EPA did not randomly select the survey recipients, 
data from these questionnaires was not used to develop national 
estimates.
5. POTW Survey
    EPA distributed the Publicly Owned Treatment Works (POTW) survey in 
November 1997. The Agency designed this survey to estimate benefits 
associated with implementation of the MP&M regulations and to estimate 
possible costs and burden that POTWs might incur in writing MP&M 
permits or other control mechanisms. The Agency sent the POTW survey to 
150 POTWs with flow rates greater than 0.50 million gallons per day. 
EPA randomly selected the recipients from the 1992 Needs Survey Review, 
Update, and Query System Database (RUQus). The Agency divided the POTW 
sample into two strata by daily flow rates: 0.50 to 2.50 million 
gallons, and 2.50 million gallons or more.
    In addition to the total volume of wastewater treated at the site, 
the POTW survey requested the number of industrial permits written, the 
cost to write the permits, the permitting fee structure, the percentage 
of industrial dischargers covered by National Categorical Standards 
(i.e., effluent guidelines), and the percentage of permits requiring 
expensive administrative activities. EPA used this information to 
estimate administrative burden and costs. In addition, EPA requested 
information on the use or disposal of sewage sludge generated by the 
POTW. The Agency only required POTWs that received discharges from an 
MP&M facility to complete those questions. The sewage sludge 
information requested included the amount generated, use or disposal 
method, metal levels, use or disposal costs, and the percentage of 
metal loadings from MP&M facilities. The Agency used this information 
to assess the potential changes in sludge handling resulting from the 
MP&M rule and to estimate economic benefits to the POTW (See Section 
XIX.B.2 for a discussion of the results of the POTW survey.)

C. Wastewater Sampling and Site Visits

    The Agency visited 201 MP&M sites to collect information about MP&M 
unit operations, water use practices, pollution prevention and 
treatment technologies, and waste disposal methods, and to evaluate 
sites for potential inclusion in the MP&M sampling program (described 
below). In general, the Agency visited sites to encompass the range of 
sectors, unit operations, and wastewater treatment technologies within 
the MP&M industry.
    The Agency based site selection on information contained in the 
MP&M screener and detailed surveys. The Agency also contacted regional 
EPA personnel, state environmental agency personnel, and local 
pretreatment coordinators to identify MP&M sites believed to be 
operating in-process source reduction and recycling technologies or 
end-of-pipe wastewater treatment technologies. The Agency also 
attempted to visit sites of various sizes. EPA visited sites with 
wastewater flows ranging from less than 200 gallons per day to more 
than 1,000,000 gallons per day. Site-specific selection criteria are 
discussed in site visit reports (SVRs) prepared for each site visited 
by EPA.
    In addition to performing site visits, EPA conducted wastewater 
sampling episodes at 72 sites to obtain data on the characteristics of 
MP&M wastewater and solid wastes, and to assess the following: The 
loading of pollutants to surface waters and POTWs from MP&M sites; the 
effectiveness of technologies designed to reduce and remove pollutants 
from MP&M wastewater; design and operational parameters; and the 
variation of MP&M wastewater characteristics across unit operations, 
metal types processed in each unit operation, and sectors.
    The Agency used information collected during MP&M site visits to 
identify candidate sites for sampling. The Agency used the following 
general criteria to select sites for sampling:
     The site performed MP&M unit operations EPA was evaluating 
for development of the MP&M regulation;
     The site processed metals through MP&M unit operations for 
which the metal type/unit operation combination needed to be 
characterized for the sampling database;
     The site performed in-process source reduction, recycling, 
or end-of-pipe treatment technologies that EPA was evaluating for 
technology option development; and
     The site performed unit operations in a sector that EPA 
was evaluating for development of the MP&M regulation.
The Agency also attempted to sample at sites of various sizes. EPA 
sampled at sites with wastewater flows ranging from less than 200 
gallons per day to more than 1,000,000 gallons per day.
    In addition, EPA worked with several stakeholders to collect site 
visit and sampling data from MP&M facilities. Following the 1995 
proposal of the Phase I MP&M rule, the Association of American 
Railroads (AAR), the Hampton Roads Sanitation District (HRSD), and the 
Los Angeles County Sanitation Districts (LACSD) proposed potential 
sampling sites to the Agency, and EPA visited these sites to identify 
candidates for sampling. After conducting site visits, EPA selected 
five sites for sampling episodes to characterize end-of-pipe treatment 
technologies in metal finishing and aircraft parts job shops and the 
railroad and shipbuilding industrial sectors. EPA prepared detailed 
sampling plans based on the information collected during the five site 
visits, and supported AAR, HRSD and LACSD sampling episodes for the 
collection of wastewater samples, and EPA prepared the sampling episode 
reports.
    The Agency collected the following types of information during each 
sampling episode:
     Dates and times of sample collection;
     Flow data corresponding to each sample;
     Production data corresponding to each sample of wastewater 
from MP&M unit operations;
     Design and operating parameters for source reduction, 
recycling, and treatment technologies characterized during sampling;
     Information about site operations that had changed since 
the site visit or that were not included in the SVR; and
     Temperature and pH of the sampled wastestreams.
    EPA documented all data collected during sampling episodes in the

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sampling episode report (SER) for each sampled site which are located 
in the MP&M Administrative Record. Non-confidential information from 
these reports is available in the public record for this proposal. For 
detailed information on sampling and preservation procedures, 
analytical methods, and quality assurance/quality control procedures 
see the Technical Development Document for today's proposed rule.

D. Industry Submitted Data

    EPA evaluated other industry data in developing the MP&M effluent 
guidelines. The data sources reviewed include: public comments to the 
1995 MP&M Phase I proposed rule; the Metal Finishing F006 Benchmark 
Study (September 1998); data supporting the 180-Day Accumulation Time 
Under RCRA for Waste Water Treatment Sludges From the Metal Finishing 
Industry Final Rule (65 FR 12377, March 8, 2000); data provided by the 
Aluminum Anodizing Council (AAC), the American Wire Producers 
Association (AWPA), and the Aerospace Association; data and storm water 
pollution prevention plans provided by several shipbuilding sites, and 
data from periodic compliance monitoring reports/discharge monitoring 
reports for several sites that were part of EPA's wastewater sampling 
program. Data submitted with the MP&M Phase I comments did not include 
the quality control data required to verify the accuracy of sample 
analyses and, therefore, EPA did not use the data. These data sources 
are located in the MP&M Administrative Record. Non-confidential 
information is available in the public record for this proposal.

E. Summary of Public Participation

    EPA has met regularly with industry trade associations and their 
members at various association annual meetings and conferences. There 
are over 20 trade associations that represent facilities that were part 
of the initial scope of the MP&M proposed rule. These trade 
associations have formed an informal coalition (referred to as the 
``MP&M'' coalition) that coordinates regular meetings with 
representatives from the various affected industries. In the past year, 
EPA has also participated in several of the Small Business 
Administration's ``Small Business Roundtable'' meetings.
    As discussed in detail in Section XXII.C, EPA conducted outreach 
and convened a Small Business Advocacy Review Panel. For this proposed 
rule, the small entity representatives included nine small MP&M 
facility owner/operators, one small municipality, and the following six 
trade associations representing different sectors of the industry: 
National Association of Metal Finishers (NAMF)/Association of 
Electroplaters and Surface Finishers (AESF)/MP&M Coalition; the 
Association Connecting Electronics Industries (also known as IPC); 
Porcelain Enamel Institute; American Association of Shortline Railroads 
(ASLRA); Electronics Industry Association (EIA); and the American Wire 
Producers Association (AWPA).
    Because many facilities affected by this proposal are indirect 
dischargers, the Agency also conducted outreach to publicly owned 
treatment works (POTWs) individually and through the Association of 
Municipal Sewerage Agencies (AMSA). EPA also conducted a survey of 150 
POTWs to assess the burden associated with implementing the proposed 
MP&M rule (see Section V.B.5 above for discussion of the POTW survey). 
In addition, EPA made a concerted effort to consult with pretreatment 
coordinators and state and local entities that will be responsible for 
implementing this regulation.
    EPA sponsored three stakeholders' meetings between November 1997 
and May 2000. Two meetings were held in Washington, DC, and the third 
was held in Chicago, IL. The primary objectives of the meetings were to 
present the Agency's current thinking regarding the technology bases 
for the MP&M proposed rule and to solicit comments, issues, and new 
ideas from interested stakeholders, including members of environmental 
groups.
    EPA provided information on the potential technology options and 
in-process pollution prevention practices as well as the potential 
subcategories. EPA also provided preliminary information on pollutant 
reductions, compliance costs, and potential monitoring flexibility.
    Most recently, EPA has put up a website (http://www.epa.gov/ost/
guide/mpm) to provide ongoing information on the MP&M project. The site 
includes background information, links to related documents, and 
information presented at MP&M stakeholders meetings.

VI. Industry Subcategorization

A. Methodology and Factors Considered for Basis of Subcategorization

    EPA may divide a point source category (e.g., MP&M) into groupings 
called ``subcategories'' to provide a method for addressing variations 
between products, raw materials, processes, and other factors which 
result in distinctly different effluent characteristics. Regulation of 
a category by using formal subcategories provides that each subcategory 
has a uniform set of effluent limitations which take into account 
technological achievability and economic impacts unique to that 
subcategory. In some cases, effluent limitations within a subcategory 
may be different based on consideration of the factors described in 
section 304(b)(2)(b) of the CWA, 33 U.S.C. 1314(b)(2)(B). The CWA 
requires EPA, in developing effluent limitations guidelines and 
pretreatment standards, to consider a number of different 
subcategorization factors. The statute also authorizes EPA to take into 
account other factors that the Agency deems appropriate. Stakeholders 
specifically suggested that EPA consider subcategories based on 
industry sector or type of activity within an industry sector (e.g., 
repair and maintenance versus manufacturing), some of which appear to 
have very low baseline pollutant loadings.
    EPA considered the following factors in its evaluation of potential 
MP&M subcategories:
     Unit operation;
     Activity;
     Raw materials;
     Products;
     Size of site;
     Location;
     Age;
     Nature of the waste generated;
     Economic impacts;
     Treatment costs;
     Total energy requirements;
     Air pollution control methods;
     Solid waste generation and disposal; and
     POTW burden.
One result of grouping similar facilities into subcategories is the 
increased likelihood that the regulations are practicable, and it 
diminishes the need to address variations between facilities through a 
variance process (Weyerhaeuser Co. V. Costle, 590 F.2d 1011, 1053 (D.C. 
Cir. 1978)).
    EPA considered subcategorizing the MP&M category by industrial 
sector (e.g., aerospace, aircraft, bus and truck, electronic equipment, 
hardware, household equipment, instruments, job shops, mobile 
industrial equipment, motor vehicles, office machines, ordnance, 
precious metals and jewelry, printed wiring boards, railroad, ships and 
boats, stationary industrial equipment, and miscellaneous metal 
products). Sectors are broadly defined and not only include 
manufacturing and repair facilities within the sector (e.g., 
shipbuilding facilities in the ship and boat sector), but also include 
facilities that produce products that are used within the sector (e.g., 
a facility that

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manufactures hydraulic pumps used on ships is also in the ship and boat 
sector). The Agency determined that subcategorization based solely on 
industrial sector would require much more detailed subcategorization 
scheme than the approach proposed (see below). Adopting a 
subcategorization scheme based on industrial sector would complicate 
the implementation of the limitations and standards because permit 
writers might be required to develop facility-specific limitations 
across multiple subcategories.
    The Agency determined that wastewater characteristics, unit 
operations, and raw materials used to produce products within a given 
sector are not always the same from site to site, and they are not 
always different from sector to sector. Within each sector, sites can 
perform a variety of unit operations on a variety of raw materials. For 
example, a site in the aerospace sector may primarily machine aluminum 
missile components and not perform any surface treatment other than 
alkaline cleaning. Another site in that sector may electroplate iron 
parts for missiles and perform little or no machining. Wastewater 
characteristics from these sites may differ because of the different 
unit operations performed and different raw materials used.
    Based on the analytical data collected for this rule, EPA has not 
found a statistically significant difference in industrial wastewater 
discharge among industrial sectors when performing similar unit 
operations for cadmium, chromium, copper, cyanide, lead, manganese, 
molybdenum, nickel, oil & grease, silver, tin, TSS, and zinc. (The 
analytical data are available in the public record for this 
rulemaking.) For example, a facility that performs electroplating in 
the process of manufacturing office machines produces metal-bearing 
wastewater with similar chemical characteristics as a facility that 
performs electroplating in the process of manufacturing a part for a 
bus. Similarly, a facility that performs repair and maintenance on a 
airplane engine produces oil-bearing wastewater that has similar 
chemical characteristics to a facility that performs repair and 
maintenance on construction machinery.
    Most MP&M unit operations are not unique to a particular sector and 
are performed across all sectors. For example, all sectors may perform 
several of the major wastewater-generating unit operations (e.g., 
alkaline treatment, acid treatment, machining, electroplating). And, 
for the most part, the unit operations that are rarely performed (e.g., 
abrasive jet machining) are not performed in all sectors, but are also 
not limited to a single sector. Therefore, a facility in any one of the 
18 industrial sectors can generate metal-bearing or oil-bearing 
wastewater (or a combination of both) depending on what unit operations 
the facility performs.
    In addition, two facilities that may be part of the same sector may 
generate wastewater with vastly different chemical characteristics and 
thus require different types of treatment. For example, an automobile 
manufacturer and an automobile repair facility are both part of the 
motor vehicle sector. However, the automobile manufacturer may perform 
unit operations that generate metal-bearing and oil-bearing wastewater 
(aqueous degreasing, electroplating, chemical conversion coating, etc.) 
while the automobile repair facility may perform unit operations that 
only generate oil-bearing wastewater (machining, aqueous degreasing, 
impact deformation, painting, etc.).
    Due to the numerous MP&M facilities that could fall under the scope 
of multiple sectors, EPA determined that a regulation based on MP&M 
industrial sector would create a variety of implementation issues for 
State and local regulators as well as for those multiple-sector 
facilities. Therefore, as mentioned above, EPA is not proposing to use 
industrial sector to subcategorize the industry.
    In the Phase I proposal, EPA did not subcategorize the Phase I 
segment of MP&M sectors (see 60 FR 28221; May 30, 1995). As discussed 
in Section II.C, the scope of the 1995 proposal differed from today's 
proposal in that it only covered seven of the 18 MP&M industrial 
sectors. For today's proposal, EPA performed the analysis for 
determining whether or not to subcategorize considering all facilities 
under the scope of today's rule (i.e., both Phase I and II industrial 
sectors). See Section III for a discussion on the scope of today's 
proposal. Based on this analysis, EPA determined that it is necessary 
to subcategorize the MP&M industry.
    A variety of factors influenced EPA's decision to subcategorize the 
MP&M industry. First, EPA found two basic types of wastestreams in the 
industry: (1) wastewater with high metals content (metal-bearing), and 
(2) wastewater with low concentration of metals, and high oil and 
grease content (oil-bearing). The type of wastewater a facility 
generates is directly related to the unit operations it performs. For 
example, unit operations such as machining, grinding, aqueous 
degreasing, and impact or pressure deformation tend to generate a 
wastewater with high oil and grease (and associated organic pollutants) 
loadings without significant concentrations of metal pollutants. While 
other unit operations such as electroplating, conversion coating, 
chemical etching and milling, and anodizing generate higher metals 
loadings with moderate/low oil and grease concentrations.
    Although many facilities generate both metal- and oil-bearing 
wastewater, there are a large number of facilities that only generate 
oil-bearing wastewater. Such facilities are typically machine shops and 
maintenance and repair facilities. Since the wastewater at these 
facilities primarily contains oil and grease and other organic 
constituents, treatment technologies at these facilities focus on oil 
removal only and do not require the chemical precipitation step needed 
for treating metal-bearing wastewater. Treatment technologies in place 
at these facilities generally include ultrafiltration, or chemical 
emulsion breaking followed by either gravity floatation, coalescing 
plate oil/water separators, or dissolved air flotation (DAF). 
Therefore, EPA first divided the industry on the basis of unit 
operations performed and the nature of the wastewater generated, 
resulting in the following two groups: (1) metal-bearing with or 
without oily and organic constituents group; and (2) oil-bearing only 
group. As a second step, EPA performed an analysis to see if there were 
any significant differences in the subcategorization factors within the 
two basic groups.
    When looking at facilities with metal-bearing wastewater (with or 
without oil-bearing wastewater), EPA identified several groups of 
facilities which could potentially be subcategorized by dominant 
product, raw materials used, and/or nature of the waste generated. In 
two subcategories, EPA also considered economic impacts as a factor in 
subcategorization because of the reduced ability of these facilities to 
afford treatment costs. There were also two subcategories where the 
number of facilities that were not currently covered by an existing 
effluent guidelines regulation was large enough to present an 
unacceptable burden to POTWs.
    Based on the currently available data, EPA is proposing to 
subcategorize the metal-bearing (with or without oil-bearing 
wastewater) MP&M facilities into the following subcategories: non-
chromium anodizing; metal finishing job shops; printed wiring board 
facilities; steel forming and finishing facilities; and general metals 
facilities. EPA describes its rationale for

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subcategorization below (see Section VI.C for additional detailed 
discussion and applicability of each of these subcategories).
    The non-chromium anodizers are different from other MP&M facilities 
in that all of their products are primarily of one metal type--anodized 
aluminum--and most importantly, they do not use chromic acid or 
dichromate sealants in their anodizing process. Based on EPA's limited 
data for these facilities, EPA expects that these facilities have very 
low levels of metals (with the exception of aluminum) or toxic organic 
pollutants in their wastewater discharges. EPA determined that other 
MP&M facilities had much greater concentrations of a wider variety of 
metals. In addition, due to the presence of large quantities of 
aluminum, these facilities require much larger wastewater treatment 
systems to remove the large amounts of aluminum and low levels of alloy 
metals. The need for larger treatment systems results in higher costs 
and large economic impacts for this potential subcategory. EPA found 
that as many as 60 percent of the non-chromium anodizers could 
experience closures as a result of complying with the proposed 
regulation (see Section XVI for a discussion of economic impacts). 
Therefore, based on the difference in raw materials used, product 
produced, nature of the waste generated (i.e., low levels of pollutants 
discharged), treatment costs, and projected economic impacts, EPA 
concluded that a basis exists for subcategorizing the non-chromium 
anodizing facilities in the MP&M industry.
    EPA investigated whether or not to subcategorize the metal 
finishing and electroplating job shops covered by the Metal Finishing 
(40 CFR part 433) and Electroplating (40 CFR part 413) effluent 
guidelines. Although the facilities have metal types that require the 
same treatment technologies as many other metals-bearing facilities, 
EPA determined these facilities to be different due to the variability 
of their raw materials and products as well as the slightly higher 
level of economic impacts incurred as compared to other costed 
facilities. As discussed in Section VI.C.2 below, this subcategory 
includes only those facilities who perform the six operations defining 
the applicability of the Metal Finishing and Electroplating effluent 
guidelines and who are ``job shops'' by the definition provided in the 
Metal Finishing effluent guidelines (i.e., they own less than 50 
percent of the products processed on site on an annual area basis). 
(See 40 CFR 433.11). Because these facilities are job shops and perform 
work on a contract basis, they cannot always predict the type of 
plating or other finishing operations required. In addition, because 
these facilities perform work on a large variety of metal types from 
various customers, the wastewater generated at these facilities can 
vary from week to week (or even day to day). EPA performed wastewater 
sampling to specifically identify the variability in the wastewater 
generated at metal finishing job shops and found that the variability 
factors calculated solely on the analytical wastewater sampling data of 
metal finishing and electroplating job shops is higher for most 
pollutant parameters than those calculated for similar metal-bearing 
subcategories (e.g., General Metals) (see Section II.D for a discussion 
of EPA's job shop variability wastewater sampling and Section VIII.B 
for a discussion on determining limits and variability factors). In 
addition, EPA found that up to 10 percent of the indirect discharging 
metal finishing job shops subcategory could experience facility 
closures as a result of compliance with the proposed regulatory 
technology option (see Section VIII for a discussion of technology 
options). Therefore, EPA concluded that it has an appropriate basis for 
subcategorizing metal finishing and electroplating job shops.
    EPA determined that there is a basis for establishing a different 
subcategory for the printed wiring board facilities from the other 
facilities in the group of metal-bearing (with or without oil-bearing 
wastewater) facilities based on raw materials, unit operations 
performed, dominant product, and nature of the waste generated. First, 
these facilities process a more consistent mix of metal types 
(primarily copper, tin, and lead) than other MP&M facilities to produce 
a specific product. EPA has concluded that this more consistent mix of 
metal types enables the printed wiring board facilities to tailor their 
treatment technology and incorporate more of the advanced pollution 
prevention and recovery technologies (e.g., ion exchange). Printed 
wiring board facilities generally work with copper-clad laminate 
material, allowing them to target copper for removal in their 
wastewater treatment systems or recover the copper using in-process ion 
exchange. Second, these facilities apply, develop, and strip 
photoresist--a set of unit operations which is largely unique to this 
proposed subcategory. This process results in a higher concentration of 
a more consistent group of organic constituents than other facilities 
in the metal-bearing group. Finally, the nature of the wastewater 
generated at these facilities may also be different due to the fact 
that these facilities perform more lead-bearing operations (e.g., lead/
tin electroplating, wave soldering) than other MP&M facilities.
    Steel forming and finishing is another proposed subcategory under 
the metal bearing (with or without oil-bearing wastewater) group of 
MP&M facilities. These facilities perform both cold forming and 
finishing operations on steel at stand-alone facilities as well as at 
steel manufacturing facilities. EPA formerly covered these facilities 
under the 1982 Iron and Steel Manufacturing effluent guidelines (40 CFR 
part 420). Typical operations include: acid pickling, annealing, 
conversion coating (e.g., zinc phosphate, copper sulfate), hot dip 
coating and/or electroplating of steel wire or rod, heat treatment, 
welding, drawing, patenting, and oil tempering. EPA concluded that the 
basis for subcategorization is the difference in the raw material and 
dominant product at these facilities. Facilities in this subcategory 
only process steel and for the most part produce uniformly-shaped 
products such as wire, rod, bar, pipe and tube. In addition, this is 
the only subcategory where EPA is proposing to cover forming operations 
under the MP&M regulations. Effluent guidelines specific to forming 
operations exist for all other common metal types (e.g., Aluminum 
Forming (40 CFR part 467); Copper Forming (40 CFR part 468); and 
Nonferrous Metals Forming & Metal Powders (40 CFR part 471)).
    Finally, after subcategorization of the non-chromium anodizing, 
metal finishing job shops, printed wiring board facilities, steel 
forming and finishing facilities, EPA is proposing to group the 
remaining metal-bearing (with or without oil-bearing wastewater) group 
of MP&M facilities into a subcategory entitled ``General Metals.'' This 
subcategory would be a ``catch-all'' for facilities that did not fall 
into any of the previous subcategories but whose wastewater, at a 
minimum, requires metals removal and may also require the preliminary 
treatment steps of oil/water separation, chromium reduction, and 
cyanide destruction. For example, wastewater generated from most 
manufacturing operations and heavy rebuilding operations (e.g., 
aircraft/aerospace, automobile, bus/truck, railroad) would be regulated 
under the proposed General Metals subcategory.
    When looking at facilities with only oil-bearing wastewater for 
potential further subcategorization, EPA found that there were two 
types of facilities that were different from the other

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facilities in that group based on size, location, and dominant product/
activity. The first type of facility includes MP&M operations that 
occur in shipbuilding dry docks or similar structures, and the second 
includes railroad line maintenance facilities (see VI.C.8 and VI.C.9, 
respectively, for a detailed description of these proposed 
subcategories). Dry docks (and similar structures such as graving 
docks, building ways, lift barges, and marine railways) are large, 
outdoor areas exposed to precipitation that shipyards use to perform 
final assembly, maintenance, rebuilding and repair work on large ships 
and boats. Due to their size, outdoor location, low level of pollutant 
loadings discharged to the environment, and the fact this wastewater is 
unique to the shipbuilding industry, EPA believes that a basis exists 
to subcategorize shipbuilding dry docks and similar structures. This 
proposed subcategory does not include other MP&M operations that occur 
at shipyards (e.g., shore-side operations).
    Similarly, railroad line maintenance facilities are outdoor 
facilities where light maintenance and cleaning of railroad cars, 
engines and car-wheel trucks occur. Due to their outdoor location, unit 
operations performed, and low level of pollutant loadings discharged to 
the environment, EPA concluded that there is a basis to subcategorize 
railroad line maintenance facilities. EPA notes that this proposed 
subcategory does not include railroad manufacturing operations or 
railroad overhaul/rebuilding facilities.
    Finally, after subcategorization of the shipbuilding dry dock and 
railroad line maintenance facilities, EPA is proposing to group the 
remaining oily-bearing wastewater group of MP&M facilities into a 
subcategory entitled ``Oily Wastes.'' This subcategory would be a 
``catch-all'' for facilities that did not fall into the two above 
``oily'' subcategories but whose wastewater does not have metals 
loadings at levels where they can be effectively treated. Following 
further analysis, EPA has decided not to propose pretreatment standards 
for indirect discharging facilities in the shipbuilding dry dock and 
railroad line maintenance subcategories (see Section XII for a 
discussion pertaining to pretreatment standards).

B. Proposed Subcategories

    As discussed above in Section VI.A, EPA has determined that a basis 
exists for dividing the MP&M category into the following subcategories 
for the proposed rule: General Metals, Non-Chromium Anodizing, Metal 
Finishing Job Shops, Printed Wiring Boards, Steel Forming and 
Finishing, Oily Wastes, Railroad Line Maintenance, and Shipbuilding Dry 
Dock. In Section VI.C below, EPA describes each subcategory and defines 
the applicability of the rule for facilities in each subcategory. EPA 
notes that with the exception of the two general subcategories (General 
Metals and Oily Wastes), the remaining proposed subcategories would not 
have been relevant to the subcategorization of the Phase I MP&M 
proposal. The facilities that have been further subcategorized in 
today's proposal were all part of the Phase II MP&M sectors (see 
Section II.C for a discussion on the 1995 Phase I proposal).
    EPA believes its proposed subcategories make sense, for the reasons 
discussed above, but requests comment on other possible subcategories. 
In particular, it has been suggested that the large General Metals 
subcategory be further subdivided into industrial sectors based on 
preliminary analyses which suggest that discharges from some sectors 
may be low enough to warrant exclusion from this regulation. Some of 
the wastewaters in these sectors may be covered by other effluent 
guidelines. EPA requests comment on further subdivision of the General 
Metals subcategory. Commenters should include data to support their 
suggestions where possible.

C. General Description of Facilities in Each Subcategory

1. General Metals
    As discussed above in Section VI.A, EPA has created the General 
Metals subcategory as a ``catch-all'' for MP&M facilities that 
discharge metal-bearing wastewater (with or without oil-bearing 
wastewater) that do not fit the applicability of the Printed Wiring 
Board, Non-Chromium Anodizing, Metal Finishing Job Shops, or Steel 
Forming and Finishing subcategories. Therefore, the General Metals 
subcategory may include facilities from 17 of the 18 MP&M industrial 
sectors (i.e., all except the printed wiring board sector). This 
subcategory also includes General Metals facilities that are owned and 
operated by states and municipalities. (See Section III for a 
discussion on the general scope of today's proposal). General Metals 
facilities likely perform manufacturing or heavy rebuilding of metal 
products, parts, or machines. Facilities that perform metal finishing 
or electroplating operations on-site, but do not meet the definition of 
a job shop (i.e., captive shops), would fit in the applicability of the 
General Metals subcategory.
    EPA estimates that there are approximately 26,000 indirect 
dischargers and 3,800 direct dischargers that could be covered by this 
proposed subcategory. EPA currently regulates 26 percent of the 
facilities in this subcategory by existing effluent guidelines. Based 
on responses to its questionnaires, the Agency estimates that the Metal 
Finishing (40 CFR part 433) and Electroplating (40 CFR part 413) 
effluent guidelines cover approximately 16 percent of these facilities 
and other metals related effluent guidelines (such as those discussed 
in Section II.B.) cover a portion of the wastewater discharges at an 
additional 10 percent of these facilities.
    EPA is proposing to exclude, from the MP&M regulations, indirect 
discharging facilities that would fall into the General Metals 
subcategory when they discharge less than or equal to 1 million gallons 
per year (MGY) of MP&M process wastewater to the POTW. (See Sections 
II.D, III, and XII for discussions on the proposed low flow cutoff and 
its impact on POTW burden reduction). In cases where these General 
Metals facilities discharge less than or equal to 1 MGY to a POTW, 
these pretreatment standards proposed today do not apply; however, 
facilities are still subject to other applicable pretreatment 
standards, including those established under parts 413 and 433. See 
Sections IX, XI, and XII of this preamble for information on compliance 
costs, pollutant reductions, and economic impacts associated with the 
MP&M rule for the General Metals subcategory.
2. Metal Finishing Job Shops
    Facilities in the Metal Finishing Job Shops subcategory must meet 
the following criteria: (1) Discharge wastewater from one or more of 
the six operations identified in the applicability of the Metal 
Finishing (40 CFR part 433) and Electroplating (40 CFR part 413) 
effluent limitations guidelines regulations; and (2) must meet the 
definition of a job shop. The six identifying operations are: 
Electroplating, Electroless Plating, Anodizing, Coating (chromating, 
phosphating, passivation, and coloring), Chemical Etching and Milling, 
and Printed Circuit Board Manufacture (i.e, Printed Wiring Boards). As 
in the Metal Finishing effluent guidelines (40 CFR part 433), EPA 
defines a ``job shop'' as ``a facility which owns not more than 50 
percent (on an annual area basis) of the materials undergoing metal 
finishing.'' EPA is proposing to include printed

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wiring board job shops in this subcategory based on the unique 
economics of job shop operation. However, EPA solicits comment on the 
variability of the raw materials, products, and wastewater at printed 
wiring board job shops. EPA also solicits comment on including printed 
wiring board job shops under this subcategory or whether EPA should 
include them in the Printed Wiring Board Subcategory (see Section 
VI.C.4 for a discussion on the Printed Wiring Board Subcategory).
    The Agency estimates that there are approximately 1,500 indirect 
dischargers and 15 direct dischargers in the proposed Metal Finishing 
Job Shops subcategory. EPA currently regulates all facilities in this 
subcategory by the existing Metal Finishing or Electroplating effluent 
guidelines and standards. EPA is proposing to cover all of these 
facilities under this proposed rule. Therefore, under today's proposal, 
facilities subject to the Metal Finishing Job Shops subcategory would 
no longer be covered by the effluent limitations guidelines and 
standards in 40 CFR part 413 or 40 CFR part 433. (See Sec. 438.20(a)). 
EPA estimates that today's proposal could reduce pollutant loadings 
from this subcategory by an additional 1.75 million toxic pound 
equivalents \2\ annually over the reductions currently achieved.
---------------------------------------------------------------------------

    \2\ EPA uses toxic pound-equivalents to indicate the amount of 
toxicity that a pollutant may exert on human health and aquatic 
life. The Agency calculates toxic pound-equivalents by multiplying 
the mass of pollutants discharged (or removed) by that pollutant's 
toxic weighting factor (TWF). EPA develops TWFs using a combination 
of toxicity data on human health and aquatic life and are relative 
to the toxicity of copper. (See Section XVII of today's notice or 
the Cost-Effectiveness Analysis Document for this proposed rule for 
a more detailed discussion of toxic weighting factors).
---------------------------------------------------------------------------

    EPA has identified approximately 30,000 facilities that meet the 
definition of job shop but do not discharge wastewater from one or more 
of the six identifying metal finishing operations as defined in 40 CFR 
part 433. EPA does not consider such job shops to be part of the Metal 
Finishing Job Shops subcategory. For example, these other job shops 
perform assembly, painting, and machining on a contract basis and are 
likely to fall in the General Metals or Oily Waste subcategories.
    EPA is considering an alternative compliance option for this 
subcategory which includes the demonstration of specified pollution 
prevention practices for all facilities in the subcategory (or possibly 
only those facilities below a specified flow cutoff). See Section XXI.D 
for a discussion on the pollution prevention alternative for Metal 
Finishing Job Shops. Also see Sections IX, XI, and XII of this preamble 
for information on compliance costs, pollutant reductions, and economic 
impacts for the Metal Finishing Job Shops subcategory.
3. Non-Chromium Anodizing
    Facilities covered under the proposed Non-Chromium Anodizing 
subcategory must perform aluminum anodizing without the use of chromic 
acid or dichromate sealants in their MP&M operations. Anodizing is a 
surface conversion operation used to alter the properties of aluminum 
for better corrosion resistence and heat transfer. Generally, non-
chromium anodizing facilities perform sulfuric acid anodizing; however, 
facilities can use other acids, such as oxalic acid, for aluminum 
anodizing. EPA is not including anodizers that use chromic acid or 
dichromate sealants under this subcategory. EPA is proposing to cover 
those facilities in the General Metals subcategory or the Metal 
Finishing Job Shops subcategory (if they operate as a job shop). EPA 
solicits comment on the chromium content of sulfuric acid anodizing 
baths, anodizing dyes/sealants, and other wastewater from sulfuric acid 
anodizing.
    EPA estimates that there are approximately 190 indirect dischargers 
and, to date, has not identified any direct dischargers in the Non-
Chromium Anodizing subcategory. The wastewater generated at non-
chromium anodizing facilities contains very low levels of metals (with 
the exception of aluminum) and toxic organic pollutants. In addition, 
as discussed in Section VI.A, above, EPA determined that compliance 
with the proposed regulation would cause 60 percent of the indirect 
discharging facilities in this subcategory to close. Therefore, for the 
reasons discussed in Section XII.F below, EPA is proposing to exclude 
wastewater from indirect discharging non-chromium anodizing facilities 
(that also do not use dichromate sealants) from the MP&M categorical 
pretreatment standards. Such facilities would still need to comply with 
the pretreatment standards of the Metal Finishing (40 CFR part 433) or 
Electroplating (40 CFR part 413) effluent guidelines for their non-
chromium anodizing wastewater and the general pretreatment standards at 
40 CFR part 403. EPA is proposing limits for direct dischargers in this 
subcategory. EPA solicits comment on whether the applicable standards 
for indirect discharging non-chromium anodizers should be transferred 
from 40 CFR part 433 to the MP&M regulation in order to include all 
non-chromium anodizers under one regulation. Because today's proposal 
includes a monitoring waiver for pollutants that are not present (see 
Section XXI.C.1 for a discussion on the monitoring waiver), the Agency 
believes that transferring the pretreatment standards for these 
facilities to the MP&M regulation would allow non-chromium anodizing 
indirect dischargers to reduce the number of parameters for which they 
have to monitor. See Section IX, XI, and XII of this preamble for 
information on compliance costs, pollutant reductions, and economic 
impacts for the Non-Chromium Anodizing subcategory.
    Some facilities that could potentially fall into the Non-Chromium 
Anodizing subcategory may also perform other metal surface finishing 
operations at their facilities. If these facilities commingle their 
wastewater from their non-chromium anodizing operations with wastewater 
from other surface finishing operations (e.g., chromic acid anodizing, 
electroplating, chemical conversion coating, etc.) for treatment, they 
would not be covered by the Non-Chromium Anodizing subcategory. 
Instead, the General Metals or Metal Finishing Job Shop subcategories 
would apply. However, for facilities that discharge their non-chromium 
anodizing wastewater separate from their other surface finishing 
wastewater, control authorities and permit writers would apply the 
appropriate limits to each discharge.
4. Printed Wiring Board
    EPA is proposing the Printed Wiring Board subcategory to cover 
wastewater discharges from the manufacture, maintenance, and repair of 
printed wiring boards (i.e., circuit boards). This subcategory does not 
include job shops that manufacture, maintain or repair printed wiring 
boards--EPA is covering these facilities under the Metal Finishing Job 
Shops subcategory, see Section VI.C.2 above for a discussion. EPA 
currently regulates all facilities in this subcategory by the existing 
Metal Finishing or Electroplating effluent guidelines and standards. 
EPA is proposing to cover all of these facilities under this proposed 
rule. Therefore, under today's proposal, facilities subject to the 
Printed Wiring Board subcategory would no longer be covered by the 
effluent limitations guidelines and standards in 40 CFR part 413 or 40 
CFR part 433. Printed wiring board facilities perform unique operations 
including applying, developing and stripping of photoresist, lead/tin 
soldering, and wave soldering. EPA estimates that there are 
approximately 620 indirect

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dischargers and 11 direct dischargers in the proposed Printed Wiring 
Board subcategory. See Sections IX, XI, XII, and XVI of this preamble 
for information on compliance costs, pollutant reductions, and economic 
impacts for the Printed Wiring Board subcategory.
5. Steel Forming & Finishing
    Although many facilities may perform MP&M operations with steel, 
EPA is proposing to establish the Steel Forming & Finishing subcategory 
for process wastewater discharges from facilities that perform MP&M 
operations (listed in Section III) or cold forming operations on steel 
wire, rod, bar, pipe, or tube. This subcategory does not include 
facilities that perform those operations on base materials other than 
steel. In a separate notice, EPA is proposing to revise the Iron and 
Steel Manufacturing effluent guidelines. The proposed revisions to the 
Iron and Steel regulations include revising the applicability to 
exclude those facilities that EPA has determined to be appropriately 
regulated by the MP&M proposed rule. EPA based this decision on the 
information gathered during the data collection effort for the proposed 
revision to the Iron & Steel Manufacturing regulations.
    The MP&M Steel Forming & Finishing proposed subcategory does not 
cover wastewater generated from performing any hot steel forming 
operations; or wastewater from cold forming, electroplating or 
continuous hot dip coating of steel sheet, strip, or plates. As 
mentioned above, the new proposed Iron & Steel Manufacturing effluent 
guidelines cover wastewater from such operations.
    EPA estimates that there are approximately 110 indirect dischargers 
and 43 direct dischargers in the Steel Forming & Finishing subcategory 
of the proposed MP&M regulation. All facilities in this subcategory 
have permits or other control mechanisms under the existing Iron and 
Steel Manufacturing regulation (40 CFR part 420).
    EPA is proposing to cover wastewater from these steel forming and 
finishing operations, regardless of whether they occur at a stand-alone 
facility or at a steel manufacturing facility. When a steel 
manufacturing facility performs these MP&M steel forming and finishing 
operations and commingles the wastewater for treatment with wastewater 
from other non-MP&M unit operations, control authorities (e.g., POTWs) 
and permit writers will need to set limits which account for both the 
MP&M and the Iron & Steel regulations. As mentioned previously, EPA 
refers to this approach as the combined waste stream formula or the 
building block approach. For facilities that choose to discharge their 
MP&M Steel Forming & Finishing wastewater separate from their Iron & 
Steel wastewater, control authorities and permit writers will apply the 
appropriate limits to each discharge. See Sections IX, XI, and XII of 
this preamble for information on compliance costs, pollutant 
reductions, and economic impacts for the Steel Forming & Finishing 
subcategory.
6. Oily Wastes
    EPA has created the Oily Wastes subcategory as a ``catch-all'' for 
MP&M facilities that discharge only oil-bearing wastewater and that do 
not fit the applicability of the other MP&M subcategories. EPA is 
defining the applicability of this subcategory by the presence of 
specific unit operations. Facilities in the Oily Wastes subcategory 
must not fit the applicability of the Railroad Line Maintenance or 
Shipbuilding Dry Dock subcategories and must only discharge wastewater 
from one or more of the following MP&M unit operations: alkaline 
cleaning for oil removal, aqueous degreasing, corrosion preventive 
coating, floor cleaning, grinding, heat treating, impact deformation, 
machining, pressure deformation, solvent degreasing, testing (e.g., 
hydrostatic, dye penetrant, ultrasonic, magnetic flux), painting, steam 
cleaning, and laundering. EPA is defining ``corrosion preventive 
coating'' to mean the application of removable oily or organic 
solutions to protect metal surfaces against corrosive environments. 
Corrosion preventive coatings include, but are not limited to: 
petrolatum compounds, oils, hard dry-film compounds, solvent-cutback 
petroleum-based compounds, emulsions, water-displacing polar compounds, 
and fingerprint removers and neutralizers. Corrosion preventive coating 
does not include electroplating, painting, chemical conversion coating 
(including phosphate conversion coating) operations. EPA is soliciting 
comment on the differences in metals content of wastewater generated 
from ``light'' phosphoric acid operations (such as some phosphoric acid 
etching operations and cleaning operations using phosphoric acid 
solutions) and from phosphate conversion coating. EPA is considering 
including phosphoric acid etching and cleaning using phosphoric acid 
solutions in the definition of ``oily operations'' discussed above. 
However, the Agency is not considering the inclusion of phosphate 
conversion coating as one of the ``oily operations.'' Based on EPA's 
database for this proposal, EPA believes that wastewater generated from 
phosphate conversion coating operations contains high levels of zinc 
and manganese.
    If a facility discharges wastewater from any of the above listed 
operations but also discharges wastewater from other MP&M operations, 
it does not meet the criteria of the Oily Wastes subcategory. 
Facilities in this subcategory are predominantly machine shops or 
maintenance and repair shops. EPA has determined that other MP&M unit 
operations generate metal-bearing wastewater or combination metal- and 
oil-bearing wastewater and require different treatment technology 
(i.e., chemical precipitation). EPA included wastewater from floor 
cleaning and testing operations based on review of the analytical data 
that confirmed little or no metals content in these two streams. This 
subcategory also includes state- and municipally-owned facilities only 
performing the listed operations.
    Like the General Metals subcategory, the Oily Wastes subcategory 
may include a number of facilities from each of 17 of the 18 MP&M 
industrial sectors (i.e., all except the printed wiring board sector). 
(See Section III for a discussion on the general scope of today's 
proposal).
    EPA estimates that there are approximately 28,500 indirect 
dischargers and 900 direct dischargers in the Oily Wastes subcategory. 
EPA has concluded that less than 1 percent of the MP&M process 
wastewater discharged from facilities in this subcategory are covered 
by an existing effluent guideline.
    For the reasons stated in Section XII, EPA is proposing to exclude 
from the MP&M regulations indirect discharging facilities that would 
fall into the Oily Wastes subcategory when they discharge less than or 
equal to 2 MGY of MP&M process wastewater to the POTW. EPA is also 
seriously considering a higher flow cutoff of 3 MGY for these indirect 
dischargers. See Sections IX, XI, XII of this preamble for information 
on compliance costs, pollutant reductions, and economic impacts for the 
Oily Wastes subcategory.
7. Railroad Line Maintenance
    EPA has developed the Railroad Line Maintenance subcategory to 
cover facilities that perform routine cleaning and light maintenance on 
railroad engines, cars, and car-wheel trucks and similar parts or 
machines. More specifically these facilities only discharge wastewater 
from MP&M unit

[[Page 445]]

operations that EPA defines as oily operations (see Section VI.C.6, 
above) and/or washing of final product. For other primarily oily 
subcategories (oily wastes and shipbuilding dry docks), EPA does not 
consider the unit operation ``washing of final product'' an MP&M 
``oily'' operation; however, EPA has reviewed the analytical wastewater 
sampling data for this wastestream at railroad line maintenance 
facilities and determined that there is little or no metal content. 
This subcategory does not include railroad manufacturing facilities or 
railroad overhaul or heavy maintenance facilities. Railroad line 
maintenance facilities are similar to facilities in the Oily Wastes 
subcategory in that they produce oil-bearing wastewater and do not 
perform MP&M operations that generate wastewater that require metals 
removal treatment technology.
    EPA estimates that there are approximately 800 indirect dischargers 
and 35 direct dischargers in the Railroad Line Maintenance 
subcategories. The wastewater generated at railroad line maintenance 
facilities contains very low levels of metals and toxic organic 
pollutants. For the reasons discussed in Section XII, EPA is proposing 
to exclude wastewater from indirect discharging railroad line 
maintenance facilities from the MP&M regulations. However, EPA is 
proposing to regulate conventional pollutants for direct dischargers in 
this subcategory. See Sections IX, XI, and XII of this preamble for 
information on compliance costs, pollutant reductions, and economic 
impacts for the Railroad Line Maintenance subcategory.
8. Shipbuilding Dry Dock
    EPA has created the Shipbuilding Dry Dock subcategory to 
specifically cover MP&M process wastewater generated in or on dry docks 
and similar structures such as graving docks, building ways, marine 
railways and lift barges at shipbuilding facilities (or shipyards). 
Shipbuilding facilities use these structures to perform maintenance, 
repair or rebuilding of existing ships, or the final assembly and 
launching of new ships (including barges). Shipbuilders use these 
structures to reach surfaces and parts that would otherwise be under 
water. Since dry docks and similar structures include sumps or 
containment systems, they also enable shipyards to control the 
discharge of pollutants to the surface water. Typical MP&M operations 
that occur in dry docks and similar structures include: abrasive 
blasting, hydroblasting, painting, welding, corrosion preventive 
coating, floor cleaning, aqueous degreasing, and testing (e.g., 
hydrostatic testing). Not all of these unit operations generate 
wastewater. EPA is also proposing to cover wastewater generated when a 
shipyard cleans a ship's hull in a dry dock (or similar structure) for 
removal of marine life (e.g., barnacles) only when in preparation for 
performing MP&M operations. EPA discusses typical MP&M unit operations 
in Section III.
    EPA is proposing that this subcategory only cover wastewater 
generated from MP&M operations that occur in or on these structures. 
The Agency is not including MP&M process wastewater that is generated 
at other locations at the shipyard (``on-shore'' operations) in this 
proposed subcategory. EPA expects that wastewater from these ``on-
shore'' shipbuilding operations (e.g., electroplating, plasma arc 
cutting) will fall under either the General Metals or Oily Wastes 
subcategories of the proposed MP&M regulation. Also, EPA is not 
including wastewater generated on-board ships when they are afloat 
(i.e., not in dry docks or similar structures). For U.S. military 
ships, EPA is in the process of establishing standards to regulate 
discharges of wastewater generated on-board these ships when they are 
in U.S. waters and are afloat under the Uniform National Discharge 
Standards (UNDS) pursuant to section 312(n) of the CWA. (See 64 FR 
25125, May 10, 1999). However, when ships are located in dry docks or 
similar structures, EPA is proposing to cover process wastewater 
generated and discharged from MP&M operations inside and outside the 
vessel (including bilge water).
    EPA identified three other types of water streams in or on dry 
docks and similar structures: flooding water, dry dock ballast water, 
and storm water. Flooding water enters and exits the dry dock or 
similar structure prior to performing any MP&M operations. For example, 
in a graving dock, the gates are opened allowing flooding water in and 
ships to float inside the chamber. Then the flooding water is drained, 
leaving the ship's exterior exposed so shipyard employees can perform 
repair and maintenance on the ship's hull. Dry dock ballast water 
serves a similar purpose. It is used to lower (or sink) the dry dock so 
that a ship can float over it. Then the dry dock ballast water is 
pumped out, raising the dry dock with the ship on top. Finally, since 
these structures are located outdoors and are exposed to the elements, 
storm water may fall in or on the dry dock or similar structures. EPA 
is proposing to exclude all three of these water streams from the MP&M 
regulation. Flooding water and dry dock ballast water do not come into 
contact with MP&M operations. In addition, EPA has determined that 
storm water at these facilities is covered by EPA's recent Storm Water 
Multi-Sector General permit, similar general permits issued by 
authorized states, and individual storm water permits. In general, 
storm water permits at shipyards include best management practices 
(BMPs) that are designed to prevent the contamination of storm water. 
For example, these practices include sweeping of areas after completion 
of abrasive blasting or painting. If EPA were to cover storm water in 
dry docks (or similar structures) under today's proposed rule, it would 
be unlikely that EPA would set numerical limits similar to those it is 
proposing for process wastewater. Most likely, EPA would set BMPs 
similar to those currently used in the storm water permits. Therefore, 
in an effort to avoid duplication of coverage, EPA is not covering 
storm water in dry docks (or similar structures) under today's 
proposal.
    EPA estimates that there are 6 indirect dischargers and 6 direct 
dischargers in the Shipbuilding Dry Dock subcategory. The Agency notes 
that many shipbuilders operate multiple dry docks (or similar 
structures) and that this is the number of estimated facilities (not 
dry docks) that discharge MP&M process wastewater from dry docks (and 
similar structures). Many shipyards only perform dry MP&M unit 
operations in their dry docks (and similar structures) or do not 
discharge wastewater generated in dry docks (and similar structures) 
from MP&M unit operations. Many shipyards prefer to handle this 
wastewater as hazardous, and contract haul it off-site due to the 
possible presence of copper (used as anti-foulant) in paint chips from 
abrasive blasting operations. EPA has determined that shipyards 
currently discharging MP&M wastewater from dry docks have oil/water 
separation technology in place, such as dissolved air flotation (DAF).
    The wastewater discharged from dry docks and similar structures 
contains very low levels of metals and toxic organic pollutants. For 
the reasons discussed in Section XII, EPA is proposing to exclude 
wastewater from indirect discharging dry docks and similar structures 
at shipbuilding facilities from the MP&M regulations. However, EPA is 
proposing to regulate conventional pollutants for direct dischargers in 
this subcategory. See Sections IX, XI, and XIII of this preamble for 
information on compliance costs, pollutant reductions, and

[[Page 446]]

economic impacts for the Shipbuilding Dry Dock subcategory.

VII. Water Use and Wastewater Characteristics

A. Wastewater Sources and Characteristics

    EPA classified the MP&M unit operations into the following three 
groups depending on their water use and discharge: (1) Unit operations 
that typically use process water and discharge process wastewater; (2) 
unit operations that typically either do not use process water or use 
process water but do not discharge wastewater; and (3) miscellaneous 
operations reported in the MP&M questionnaires by fewer than five 
respondents.
    Process wastewater includes any water that, during manufacturing or 
processing, comes into direct contact with or results from the 
production or use of any raw materials, intermediate products, finished 
products, by-products, or waste products. Process wastewater includes 
wastewater from wet air pollution control devices. For the purposes of 
the MP&M regulation, EPA does not consider non-contact cooling water or 
storm water a process wastewater nor does it consider non-aqueous 
wastes used as processing liquids, such as spent solvents or quench 
oil, as process wastewater. (See Section III for detailed discussion on 
general applicability of today's proposed rule).
    Wastewater from the operations that use process water have 
different characteristics depending on the unit operation from which 
they are derived. EPA discusses the five different types of MP&M 
process wastewater below. First, oil-bearing wastewater is typically 
generated from the use of metal shaping coolants and lubricants, 
surface preparation solutions used to remove oil and dirt from 
components, and associated rinses. Some examples of oil-bearing 
wastewater are: Machining and grinding coolants and lubricants; 
pressure and impact deformation lubricants; dye penetrant and magnetic 
flux testing; and alkaline cleaning solutions and rinses used to remove 
oil and dirt. This wastewater typically requires preliminary treatment 
to remove oil and grease. The most common type of treatment for oil-
bearing wastewater is chemical emulsion breaking followed by gravity 
separation and oil skimming. EPA also identified MP&M facilities that 
used membrane separation technologies for oil and grease removal.
    Second, hexavalent chromium-bearing wastewater typically consists 
of concentrated surface preparation or metal deposition solutions, 
sealants, and associated rinses. Some examples of hexavalent chromium-
bearing wastewater are: Chromic acid treatment solutions and rinses; 
chromate conversion coating solutions and rinses; and chromium 
electroplating solutions and rinses. This wastewater typically requires 
preliminary treatment to reduce the hexavalent chromium to trivalent 
chromium for subsequent chemical precipitation and settling. Typically, 
MP&M facilities use sodium metabisulfite or gaseous sulphur dioxide as 
reducing agents in the reduction of hexavalent chromium-bearing 
wastewater.
    Third, many surface preparation or metal deposition solutions and 
their associated rinses generate process wastewater that contains 
cyanide. Two examples of cyanide-bearing wastewater are: Cyanide-
bearing alkaline treatment solutions and rinses (typically used as a 
surface treatment step prior to electroplating with cyanide solutions) 
and cyanide-bearing electroplating solutions and rinses. This 
wastewater typically requires preliminary treatment to destroy cyanide 
and facilitate subsequent chemical precipitation and settling. MP&M 
facilities most often use sodium hypochlorite for the destruction of 
cyanide by alkaline chlorination.
    Fourth, concentrated surface preparation or metal deposition 
solutions and their associated rinses can generate process wastewater 
that contain complexed or chelated metals. In particular, electroless 
plating operations and their rinses typically produce this type of 
wastestream. This wastewater requires preliminary treatment to break 
and/or precipitate the complexes for subsequent chemical precipitation 
and settling. MP&M facilities typically use sodium borohydride, 
hydrazine, sodium hydrosulfite, or sodium dimethyldithiocarbamate (DTC) 
as reducing and precipitating agents in this preliminary treatment 
process.
    For the MP&M proposal, EPA based the estimated costs and pollutant 
removals associated with the treatment of chelated or complexed metals 
on the use of DTC. When DTC is used appropriately, it may effectively 
enhance the removal of some difficult to treat pollutants without 
impacting the environment or POTW operations. However, DTC is toxic to 
aquatic life and to activated sludge and thus can upset POTW 
operations. DTC can combine to form, or break down to, a number of 
other toxic chemicals, including thiram and ziram (both EPA registered 
fungicides) and other thiurams, other dithiocarbamates, carbon 
disulfide, and dimethylamine. EPA's pollutant of concern list (see 
below for a description of the development of this list) contained 
ziram, carbon disulfide, and N-nitrosodimethylamine. Ziram is known to 
be toxic to aquatic life at the following levels: LC50 less than 10 ug/
L (parts per billion) for several varieties of bluegill and trout; LC 
50 between 10 and 100 ug/L in other studies (AQUIRE data base at http:/
/www.epa.gov/medecotx/quicksearch.htm.) EPA solicits comment on the use 
of DTC for the treatment of chelated wastewater and its potential 
harmful effects on the environment and on POTW operations. The Agency 
is particularly interested in receiving data and information on 
alternative treatments for wastewater containing chelated or complexed 
metals.
    Finally, virtually all MP&M process wastewater contains some 
metallic pollutants. Metal shaping solutions, surface preparation 
solutions, metal deposition solutions, and surface finishing solutions 
typically produce the most concentrated metal-bearing wastewater. MP&M 
facilities most commonly use chemical precipitation (usually with 
either lime or sodium hydroxide) and settling for metals removal. Many 
facilities also use coagulants and flocculants to assist chemical 
precipitation and settling.
    As discussed in Section V.C, EPA conducted wastewater sampling 
episodes at 71 MP&M facilities to obtain data on the characteristics of 
MP&M wastewater and solid wastes, and to assess the following: the 
loading of pollutants to surface waters and POTWs from MP&M sites; the 
effectiveness of technologies designed to reduce and remove pollutants 
from MP&M wastewater; and the variation of MP&M wastewater 
characteristics across unit operations, metal types processed in each 
unit operation, and sectors. Although EPA analyzed the wastewater from 
these facilities for approximately 324 pollutant parameters (including 
conventional, nonconventional, and priority pollutants), it did not 
consider all of these pollutants for potential regulation. Rather, EPA 
reduced the list to 132 pollutants (referred to as pollutants of 
concern or POCs) for further consideration by retaining only those 
pollutants that met the following criteria:
     EPA detected the pollutant parameter in at least three 
samples collected during the MP&M sampling program.
     The average concentration of the pollutant parameter in 
samples of

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wastewater from MP&M unit operations and influents-to-treatment was at 
least five times the minimum level (ML) or the average concentration of 
effluent-from-treatment wastewater samples exceeded five times the 
minimum level. EPA defines the ML as ``the lowest level at which the 
entire analytical system must give a recognizable signal and an 
acceptable calibration point for the analyte.'' (Development Document 
for Final Effluent Limitations Guidelines and Standards for the 
Centralized Waste Treatment Industry. U.S. EPA).
     EPA analyzed the pollutant parameter in a quantitative 
manner following the appropriate quality assurance/quality control (QA/
QC) procedures. To meet this criteria, the Agency excluded wastewater 
analyses performed solely for certain semi-quantitative ``screening'' 
purposes. EPA performed these semi-quantitative analyses only in 
unusual cases (e.g. to qualitatively screen for the presence of a rare 
metal such as osmium).
    From the list of 132 pollutants that passed the editing criteria 
above, EPA selected the regulated pollutants for each subcategory. See 
Section 7 of the technical development document for more information on 
the selection of pollutants to regulate. The Agency also used the 
pollutant parameters on the POC list to calculate the pollutant 
removals for each technology option.

B. Pollution Prevention, Recycle, Reuse and Water Conservation 
Practices

    The data gathered to support this rule indicate that a number of 
pollution prevention and water conservation practices exist in the MP&M 
industry. EPA determined that some of these pollution prevention, 
recycling, and water conservation practices were broadly applicable to 
the MP&M category and included these in the technology options (see 
Section VIII.A).
    A large number of additional pollution prevention practices were 
site specific and could not be used as the basis for a national 
standard. However, EPA considers it important to make this site-
specific pollution prevention information available for possible use by 
MP&M sites. Therefore, the Technical Development Document (TDD) 
contains a summary of the pollution prevention practices identified 
during the development of this rule. EPA also collected data on water 
use and wastewater generation at facilities employing pollution 
prevention and good water use practices. The TDD contains this data and 
discusses the applicability of the more prevalent pollution practices 
identified in this category (e.g., drag-out reduction, flow reduction, 
coolant and paint curtain recycling). EPA is soliciting comment and 
data on any of the pollution prevention, recycle, reuse and water 
conservation practices that it discusses in the TDD as well as 
additional information about these types of technologies that EPA did 
not discuss in the TDD. In addition, EPA is requesting data and comment 
on its flow data from facilities with pollution prevention and good 
water use practices in place. See Section XXI.D for a discussion on a 
pollution prevention alternative that EPA is considering for facilities 
in the Metal Finishing Job Shops subcategory.

VIII. Development of Effluent Limitations Guidelines and Standards

A. Overview of Technology Options

    In developing its technology options, EPA determined that a 
different set of wastewater treatment technologies was appropriate for 
facilities that performed unit operations that produced primarily 
metal-bearing wastewater than for those facilities that performed unit 
operations that produced primarily oily wastes (see Section VI.C.6 for 
list of the unit operations that generate primarily oily only 
wastewater). EPA concluded that the following subcategories typically 
produce metal-bearing wastewater (with or without associated oily-
bearing wastestreams) and evaluated metals control technologies for 
these subcategories: General Metals, Metal Finishing Job Shops, Non-
Chromium Anodizing, Printed Wiring Boards, and Steel Forming and 
Finishing. For the remaining subcategories (Oily Wastes, Railroad Line 
Maintenance, and Shipbuilding Dry Docks), EPA evaluated oily wastewater 
treatment technologies. The following sections discuss the wastewater 
treatment technologies that EPA evaluated for each subcategory at each 
regulatory level (BPT, BAT, PSES, NSPS, and PSNS). See Section VI for a 
discussion on subcategorization.
1. Wastewater Treatment Technologies for Metal-Bearing Wastewater
    MP&M facilities in the General Metals subcategory, the Metal 
Finishing Job Shops subcategory, the Non-Chromium Anodizing 
subcategory, the Printed Wiring Board subcategory, and the Steel 
Forming and Finishing subcategory produce primarily metal-bearing 
wastewater. EPA evaluated the following four wastewater treatment 
technology options for the MP&M industry subcategories whose unit 
operations produce metal-bearing wastewater (and may also produce oily 
wastewater):
    Option 1. Segregation of wastewater streams, preliminary treatment 
steps as necessary (including oils removal using oil-water separation 
by chemical emulsion breaking), chemical precipitation using lime or 
sodium hydroxide, and sedimentation using a clarifier.
    Option 1, as well as each of the three other options considered by 
EPA for the metal-bearing wastewater subcategories, includes the 
segregation of wastestreams and preliminary treatment of certain 
wastestreams. Segregation of wastewater and subsequent preliminary 
treatment allows for the most efficient, effective, and economic means 
for removing pollutants in certain wastestreams. For example, if a 
facility segregates its oil-bearing wastewater from its metal-bearing 
wastewater, then the facility can design an oil removal treatment 
technology based on only the oily waste flow volume and not on the 
combined metal-bearing and oil-bearing wastewater flow. Therefore, 
preliminary treatment technologies are more effective and less costly 
on segregated wastestreams, prior to adding wastewater that does not 
contain the pollutants being treated with the preliminary treatment. 
EPA includes these preliminary treatment steps, as applicable whenever 
it refers to chemical precipitation and sedimentation treatment.
    As mentioned previously in Section VII (Water Use and Wastewater 
Characteristics), unit operations performed at MP&M sites produce 
wastewater with varying characteristics (i.e., oil-bearing, hexavalent 
chromium-bearing, cyanide-bearing, complexed metals). Wastewater with 
these characteristics requires preliminary treatment before the 
chemical precipitation step for metals removal. EPA included the 
following preliminary steps in Option 1 for the metal-bearing 
wastewater subcategories: removal of oil and grease through chemical 
emulsion breaking, gravity separation, and oil skimming; destruction of 
cyanide using sodium hypochlorite; reduction of hexavalent chromium to 
trivalent chromium which can subsequently be precipitated as a chromium 
hydroxide; and chemical reduction/precipitation of chelated or 
complexed metals. EPA has also included the contract hauling of any 
wastewater associated with organic solvent degreasing as part of the 
Option 1 technology.
    Option 1 consists of preliminary treatment for specific pollutants 
and end-of-pipe treatment with chemical precipitation (usually 
accomplished by raising the pH with an alkaline chemical such as lime 
or sodium hydroxide, also

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known as caustic, to produce insoluble metal hydroxides) followed by 
clarification and sludge dewatering. This treatment has been widely 
used throughout the metals industry and is well documented to be 
effective for removing metal pollutants. As with a number of previously 
promulgated regulations, EPA is proposing BPT on the basis that all 
process wastewater, except solvent-bearing wastewater, will be treated 
through chemical precipitation and clarification end-of-pipe treatment.
    Option 1 treatment systems (chemical precipitation with gravity 
clarification) sampled by EPA demonstrated effective removal for 
targeted metals. (Targeted metals are those metals that an MP&M 
facility was operating its wastewater treatment system to remove.)
    Option 2. In-process flow control and pollution prevention, 
segregation of wastewater streams, preliminary treatment steps as 
necessary (including oils removal using oil-water separation by 
chemical emulsion breaking), chemical precipitation using lime or 
sodium hydroxide, and sedimentation using a clarifier.
    Option 2 builds on Option 1 by adding in-process pollution 
prevention, recycling, and water conservation methods which allow for 
recovery and reuse of materials. As discussed in Section VII.B, 
techniques or technologies, such as centrifugation or skimming for 
metal working fluids, or water paint curtains, may in some cases save 
money for companies by allowing materials to be used over a longer 
period before they need to be disposed. Using these techniques along 
with water conservation also leads to the generation of less pollution 
and results in more effective treatment of the wastewater that is 
generated. The incorporation of pollution prevention practices can lead 
to smaller wastewater flows and increased pollutant concentrations. 
However, the treatment of metal-bearing wastewater by chemical 
precipitation is relatively independent of influent metal 
concentration. For example, a well-operated chemical precipitation and 
clarification treatment system can achieve the same effluent 
concentration with an influent stream of 1,000 gallons per minute (gpm) 
and 10 parts per million (ppm) as it can achieve with an influent 
stream which is 500 gpm and 20 ppm. In fact, within a broad range of 
influent concentrations, the more highly concentrated wastewater 
influent, when treated down to the technology effectiveness 
concentrations of a chemical precipitation and clarification treatment 
system, results in better pollutant removals and less mass of pollutant 
in the discharge. In addition, the cost of a treatment system is 
largely dependent on the size, which in turn is largely dependent on 
flow. As a result, good recycle and water conservation practices may 
result in cost savings, though there may also be associated cost 
increases, depending on site specific factors (e.g., costs associated 
with capital investment for pollution prevention equipment). Option 2 
in-process pollution prevention and water conservation technologies 
include:
     Flow reduction using flow restrictors, conductivity 
meters, and/or timed rinses, for all flowing rinses, plus 
countercurrent cascade rinsing for all flowing rinses;
     Centrifugation and recycling of painting water curtains; 
and
     Centrifugation and pasteurization to extend the life of 
water-soluble machining coolants reducing discharge volume.
    Option 3. Segregation of wastewater streams, preliminary treatment 
steps as necessary (including oils removal by ultrafiltration), 
chemical precipitation using lime or sodium hydroxide, and solids 
separation using a microfilter.
    This option differs from Option 1 in that an ultrafilter replaces 
the oil water separator for the removal of oil and grease and a 
microfilter, rather than a clarifier, follows chemical precipitation. 
EPA determined through sampling episodes that ultrafiltration systems 
are very effective for the removal of oil and grease at MP&M 
facilities. Ultrafilters sampled by EPA demonstrated effective removal 
of oil and grease. Additionally, EPA also collected treatment 
effectiveness data for solids removal after chemical precipitation 
through microfiltration. Microfilters sampled by EPA at MP&M facilities 
achieved long-term average effluent concentrations for targeted metals 
that were, in several cases, an order of magnitude lower than the long-
term averages achieved by Option 2.
    Option 4. In-process flow control and pollution prevention, 
segregation of wastewater streams, preliminary treatment steps as 
necessary (including oils removal by ultrafiltration), chemical 
precipitation using lime or sodium hydroxide, and solids separation 
using a microfilter.
    This option builds on Option 3 by adding in-process pollution 
prevention, recycling, and water conservation methods which allow for 
recovery and reuse of materials. EPA included the same water 
conservation and pollution control technologies in Option 4 as in 
Option 2.
    For all of the subcategories with metal-bearing wastewater, EPA 
determined that Option 2 costed less than Option 1 and demonstrated 
greater pollutant removals. Likewise, for all subcategories with metal-
bearing wastewater, Option 4 costed less than Option 3 and demonstrated 
greater pollutant removals. As discussed above, the incorporation of 
water conservation and pollution prevention technologies results in 
greater pollutant removals and less mass of pollutant in the discharge. 
In addition, the cost of a treatment system is largely dependent on the 
size, which in turn is largely dependent on flow. As a result, Options 
2 and 4, which include water conservation and pollution prevention, 
have smaller flows requiring treatment and are projected to cost less 
than Options 1 and 3, respectively. Therefore, for the remainder of the 
discussions in this preamble regarding technology options for 
subcategories with metal-bearing wastewater, EPA only considers Options 
2 and 4. The Agency has fully evaluated Options 1 and 3, and a 
discussion of the results of this evaluation is contained in the 
Technical Development Document. EPA requests comment on its 
determination that pollution prevention, recycle and water conservation 
result in net cost savings to facilities, and examples of any specific 
situations where this may not be true.
2. Wastewater Treatment Technologies for Oily Wastewater
    MP&M facilities in the Oily Wastes subcategory, the Railroad Line 
Maintenance subcategory, and the Shipbuilding Dry Dock subcategory 
produce primarily oil-bearing wastewater. EPA evaluated the following 
six wastewater treatment technology options for the MP&M industry 
subcategories whose unit operations produce only oily wastewater (see 
Section VI.C.6 for a discussion of oily unit operations):
    Option 5. Oil-water separation by Chemical Emulsion Breaking.
    Chemical emulsion breaking is used to break stable oil/water 
emulsions (oil dispersed in water, stabilized by electrical charges and 
emulsifying agents). A stable emulsion will not separate or break down 
without chemical treatment. Chemical emulsion breaking is applicable to 
wastewater streams containing emulsified coolants and lubricants such 
as machining and grinding coolants and impact or pressure deformation 
lubricants as well as cleaning solutions that contain emulsified oils.
    Treatment of spent oil/water emulsions involves using chemicals to 
break the emulsion followed by gravity differential separation. The 
major

[[Page 449]]

equipment required for chemical emulsion breaking includes reaction 
chambers with agitators, chemical storage tanks, chemical feed systems, 
pumps and piping. Factors to be considered for destroying emulsions are 
type of chemicals, dosage and sequence of addition, pH, mixing, heating 
requirements, and retention time. EPA describes this technology option 
in more detail in Section 8 of the Technical Development Document.
    In an effort to evaluate this technology option, EPA performed 
sampling episodes at several facilities in the Oily Wastes subcategory 
that employed chemical emulsion breaking followed by gravity separation 
and oil skimming.
    Option 6. In-process Flow Control, Pollution Prevention, and Oil-
water separation by chemical emulsion breaking.
    This option builds on Option 5 by adding in-process pollution 
prevention, recycling, and water conversation methods which allow for 
recovery and reuse of materials. EPA included the same pollution 
prevention techniques or technologies discussed in Option 2 such as 
flow reduction and reuse, paint curtain recycling and/or recirculation, 
and coolant recycling, as applicable.
    Option 7. Oil-water separation by ultrafiltration.
    In the MP&M industry, ultrafiltration is applied in the treatment 
of oil/water emulsions. In ultrafiltration, a semi-permeable 
microporous membrane performs the separation. Wastewater is sent 
through membrane modules under pressure. Water and low-molecular-weight 
solutes (for example, salts and some surfactant) pass through the 
membrane and are removed as permeate. Emulsified oil and suspended 
solids are rejected by the membrane and are removed as concentrate. The 
concentrate is reticulated through the membrane unit until the flow of 
the permeate drops. The permeate may either be discharged or passed 
along to another treatment unit. The concentrate is contained and held 
for further treatment or disposal. EPA describes this technology option 
in more detail in Section 8 of the Technical Development Document.
    In an effort to evaluate this technology option, EPA performed 
sampling episodes at several facilities in the Oily Wastes subcategory 
that employed ultrafiltration. EPA also collected data on 
ultrafiltration systems at metal-bearing facilities which segregated 
their oily wastestreams for treatment.
    Option 8. In-process Flow Control, Pollution Prevention, and Oil-
water separation by Ultrafiltration.
    This option builds on Option 7 by adding in-process pollution 
prevention, recycling, and water conversation methods which allow for 
recovery and reuse of materials. EPA included the same water 
conservation and pollution control technologies in Option 8 as in 
Option 6.
    Option 9. Oil-water Separation by Dissolved Air Flotation.
    Dissolved air flotation (DAF) is commonly used to remove suspended 
solids and dispersed oil and grease from oily wastewater. DAF is the 
process of using fine bubbles to induce suspended particles to rise to 
the surface of a tank where they can be collected and removed. The 
major components of a conventional DAF unit include a centrifugal pump, 
a retention tank, an air compressor, and a flotation tank. EPA 
describes this technology option in more detail in Section 8 of the 
Technical Development Document.
    In an effort to evaluate this technology option, EPA performed 
sampling episodes at several facilities in the Railroad Line 
Maintenance and Shipbuilding Dry Dock subcategories that employed 
dissolved air flotation (DAF). EPA compared the effluent concentrations 
achieved by these DAF systems to effluent concentration achieved by DAF 
systems in other industry categories (e.g., industrial laundries).
    Option 10. In-process Flow Control, Pollution Prevention, and Oil-
water separation by Dissolved Air Flotation.
    This option builds on Option 9 by adding in-process pollution 
prevention, recycling, and water conversation methods which allow for 
recovery and reuse of materials. EPA included the same water 
conservation and pollution control technologies in Option 10 as in 
Option 6 and 8.
    For all of the subcategories with only oily wastewater, EPA 
determined that the options that involved water conservation and 
pollution prevention costed less and removed more pollutant than those 
options that did not include these technologies or techniques. As 
discussed above, the incorporation of water conservation and pollution 
prevention technologies results in greater pollutant removals and less 
mass of pollutant in the discharge. In addition, the cost of a 
treatment system is largely dependent on the size, which in turn is 
largely dependent on flow. As a result, Options 6, 8, and 10, which all 
include water conservation and pollution prevention, cost less than 
their counterpart options (Options 5, 7, and 9, respectively) that did 
not include these pollution prevention technologies or techniques. 
Therefore, for the remainder of the discussions in this preamble 
regarding technology options for subcategories with oily wastewater, 
EPA only considers Options 6, 8, and 10. However, the Agency fully 
evaluated Options 5, 7, and 9, and discusses the results of this 
evaluation in the Technical Development Document.

B. Determination of Long-Term Averages, Variability Factors, and 
Limitations

1. Overview of Limitations Calculations
    EPA visited over 200 facilities and sampled wastewater from 71 MP&M 
facilities covering all the industrial sectors covered by this proposed 
rule. (See Section III for a discussion on applicability). In addition 
to sampling to characterize the process wastewater, EPA sampled 46 end-
of-pipe chemical precipitation and clarification treatment systems, 5 
microfilters, 5 oil-water emulsion breaking and gravity separation 
systems, 16 ultrafilters, and 4 chemical emulsion breaking and DAF 
systems. EPA reviewed the treatment data gathered and identified data 
considered appropriate for calculating limitations for the MP&M 
industry. EPA identified data from well-designed and well-operated 
treatment systems and focused on data for specific pollutants processed 
and treated on site. The data editing procedures used for this 
assessment consisted of four major steps:
     Assessment of the performance of the entire treatment 
system;
     Identification of process upsets during sampling that 
impacted the treatment effectiveness of the system;
     Identification of pollutants not present in the raw 
wastewater at sufficient concentrations to evaluate treatment 
effectiveness; and
     Identification of treatment chemicals used in the 
treatment system.

EPA describes the evaluation criteria used for each of these steps 
below. The Agency excluded data that failed one or more of the 
evaluation criteria from calculation of the limitations.
    Assessment of Treatment System Performance. EPA assessed the 
performance of the entire treatment system during sampling. The Agency 
excluded data for systems identified as not being well-designed or 
well-operated from use in calculating BPT limitations. EPA first 
identified the metals processed on site, as well as if the site 
performed unit operations likely to generate oil and grease and 
cyanide. EPA focused on these pollutants because MP&M facilities 
typically design and operate their treatment systems to treat and 
remove these

[[Page 450]]

pollutants. EPA then performed the following technical analyses of the 
treatment systems:

--Based on the pollutants processed or treated on site, EPA excluded 
data from systems that were not operated at the proper pH for removal 
of the pollutants.
--EPA excluded data from chemical precipitation and clarification 
systems that did not have solids removal indicative of effective 
treatment. In general, EPA identified as having poor solids removal 
systems that did not achieve at least 90 percent removal of total 
suspended solids (TSS) and had effluent TSS concentrations greater than 
50 milligrams per liter. EPA made site-specific exceptions to this 
rule.
--EPA excluded data from chemical precipitation and clarification 
systems at which the concentration of most of the metals present in the 
influent stream did not decrease, indicating poor treatment.

    Although EPA believes this is an appropriate practice, in order to 
focus on facilities with well-run treatment systems, it also introduces 
a risk of biasing estimates of treatment effectiveness upwards with 
respect to identifying pollutant removals on a national basis. If a 
particular metal is not able to be effectively removed by a particular 
treatment train, but its concentration fluctuates randomly over time in 
both the influent and the effluent, then retaining only data showing 
positive ``removals'' may give a misleading impression of effectiveness 
of that treatment technology nationally. Some commenters have raised 
this issue in the past particularly with respect to boron, which those 
commenters believe is not effectively removed by certain treatment 
trains where EPA's data (edited to include only decreases) appears to 
show removals. EPA is continuing to assess this concern both with 
regards to metals in general and with regards to boron in particular. 
EPA requests comment on this issue and suggestions for addressing it. 
EPA is planning to do a re-analysis of its estimates of its baseline 
load and removals for boron and will provide results of this analysis 
when available. This analysis will be placed in Section 6.8 of the 
public record.
    Identification of Process Upsets Occurring During Sampling. EPA 
reviewed the sampling episode reports for each of the sampled sites and 
identified any process upsets that resulted in poor treatment during 
one or more days of the sampling episode. EPA excluded the data 
affected by the process upsets.
    Identification of Pollutants Not Present in the Raw Wastewater at 
Sufficient Concentrations to Evaluate Removal. EPA excluded data for 
pollutants that it did not detect in the treatment influent streams at 
a sampled facility, or it detected at concentrations less than 10 times 
the minimum level. Because these proposed limitations are technology-
based, EPA requires that a facility must demonstrate pollutant removal 
through treatment in order for that data to be used in the calculation 
of effluent limitations. Therefore, the Agency determined that for a 
BPT/BAT facility to demonstrate effective treatment, the pollutant must 
be present in the wastewater at a treatable concentration--which EPA 
defined as 10 times the minimum level for this proposal. EPA also 
excluded data for pollutants that were not processed on site. In 
addition, EPA reviewed the water use practices for the sampled sites 
and excluded data from sites that may have been diluting the raw 
wastewater and reducing the concentration of pollutants processed on 
site. Because these proposed MP&M effluent guidelines include water 
conservation practices and pollution prevention technologies, EPA 
reviewed the data to ensure that the facilities it used as the basis 
for BPT limitations had these practices and technologies in place.
    Identification of Wastewater Treatment Chemicals. EPA identified 
treatment chemicals used in each of the sampled treatment systems to 
determine if the removal of the metals used as treatment chemicals were 
consistent with removal of other metals on site, indicating a well-
designed and well-operated system. If a sampled facility used a metal 
as a treatment chemical, and the facility treated the metal to a 
concentration consistent with other metals removed on site, EPA 
included the metal in calculation of the BPT limitations. If the 
sampled facility used a metal as a treatment chemical and the treatment 
system did not remove it to a concentration consistent with other 
metals removed on site, EPA excluded the treatment chemical from 
calculation of the limitations. (Note that this practice may raise 
similar concerns to those discussed above with respect to editing out 
data that do not show positive removals.) The Agency used the data 
remaining after these data editing procedures to calculate the 
limitations.

Calculation of Limitations

    The Technical Development Document and the Statistical Support 
Document contain a detailed description of the statistical methodology 
used for the calculation of limitations. EPA based the effluent 
limitations and standards in today's notice on widely-recognized 
statistical procedures for calculating long-term averages and 
variability factors. The following presents a summary of the 
statistical methodology used in the calculation of effluent 
limitations.
    Effluent limitations for each subcategory are based on a 
combination of long-term average effluent values and variability 
factors that account for variation in day-to-day treatment performance 
within a treatment plant. The long-term averages are average effluent 
concentrations that have been achieved by well-operated treatment 
systems using the proposed treatment technologies described in Section 
VIII. The purpose of the variability factor is to allow for normal 
variation in effluent concentrations. A facility that designs and 
operates its treatment system to achieve a long-term average on a 
consistent basis should be able to comply with the daily and monthly 
limitations in the course of normal operations.
    EPA developed the variability factors and long-term averages from a 
database composed of individual measurements on treated effluent based 
on EPA sampling data. EPA sampling data reflects the performance of a 
system over a three to five day period, although not necessarily over 
consecutive days.
    EPA performed the following steps in order to calculate the 
proposed limitations for each pollutant. For each subcategory, EPA 
calculated the arithmetic long-term average concentration of a 
pollutant for each facility representing the proposed treatment 
technology, and determined the median from the arithmetic average 
concentrations. For each pollutant, this median concentration is the 
long-term average (LTA) concentration that EPA used in determining the 
proposed effluent limitations.
    The Agency then used the modified delta-lognormal distribution to 
estimate daily and monthly variability factors. This is the same 
distributional model used by EPA in the final rulemakings for the Pulp 
and Paper and Centralized Waste Treatment. The modified delta-lognormal 
distribution models the data as a mixture of non-detect observations 
and measured values. EPA selected this distribution because the data 
for most analytes consisted of a mixture of measured values and non-
detects. The modified delta-lognormal distribution assumes that all 
non-detects have a value equal to the sample specific

[[Page 451]]

detection limit and that the detected values follow a lognormal 
distribution.
    The Agency fit the daily concentration data from each facility that 
had enough detected concentration values for parameter estimation to a 
modified delta lognormal distribution. The daily variability factor for 
each pollutant at each facility is the ratio of the estimated 99th 
percentile of the distribution of the daily pollutant concentration 
values divided by the expected value of the distribution of the daily 
values. (EPA assumed that the furthest excursion from the LTA that a 
well-operated plant using the proposed technology option could be 
expected to make on a daily basis was a point below which 99 percent of 
the data for that facility falls, under the assumed distribution.) The 
pollutant daily variability factor for a treatment technology is the 
average of the pollutant daily variability factors from the facilities 
with that technology. EPA calculates the daily maximum limitation as 
the product of the pollutant LTA concentration and the daily 
variability factor.
    The Agency calculates the monthly maximum limitation in much the 
same way. However, it bases the variability factor (known as the 
monthly variability factor) on the 95th percentile of the distribution 
of four-day average pollutant concentrations instead of the 99th 
percentile. Therefore, the monthly variability factor for each 
pollutant at each facility is the estimated 95th percentile of the 
distribution of the 4-day average pollutant concentration values 
divided by the expected value of the distribution of the daily values. 
The pollutant monthly variability factor for a treatment technology is 
the average of the pollutant monthly variability factors from the 
facilities with that technology. EPA calculates the maximum monthly 
average limitation as the product of the pollutant LTA concentration 
and the monthly variability factor.
    There were several instances where variability factors could not be 
calculated directly from the MP&M database because there were not at 
least two effluent values measured above the minimum detection level 
for a specific pollutant. In these cases, the sample size of the data 
is too small to allow distributional assumptions to be made. Therefore, 
in order to assume a variability factor for a pollutant, the Agency 
transferred variability factors from other pollutants that exhibit 
similar treatability characteristics within the treatment system. The 
Technical Development Document and the Statistical Support Document 
provide detailed information on the transfer of variability factors.

IX. Best Practicable Control Technology Currently Available (BPT)

    As discussed in Section II, in the guidelines for an industry 
category, EPA defines BPT effluent limits for conventional, toxic 
(priority), and non-conventional pollutants for direct discharging 
facilities. In specifying BPT, EPA looks at a number of factors. EPA 
first considers the cost of achieving effluent reductions in relation 
to the effluent reduction benefits. The Agency also considers the age 
of the equipment and facilities, the processes employed and any 
required process changes, engineering aspects of the control 
technologies, non-water quality environmental impacts (including energy 
requirements), and such other factors as the Agency deems appropriate 
(CWA 304(b)(1)(B)). Traditionally, EPA establishes BPT effluent 
limitations based on the average of the best performances of facilities 
within the industry of various ages, sizes, processes or other common 
characteristics. Where existing performance is uniformly inadequate, 
EPA may require higher levels of control than currently in place in an 
industrial category if the Agency determines that the technology can be 
practically applied. See ``A Legislative History of the Federal Water 
Pollution Control Act Amendments of 1972'', U.S. Senate Committee of 
Public Works, Serial No. 93-1, January 1973, p. 1468.
    In addition, CWA Section 304(b)(1)(B) requires a cost-
reasonableness assessment for BPT limitations. In determining the BPT 
limits, EPA must consider the total cost of treatment technologies in 
relation to the effluent reduction benefits achieved. This inquiry does 
not limit EPA's broad discretion to adopt BPT limitations that are 
achievable with available technology unless the required additional 
reductions are ``wholly out of proportion to the costs of achieving 
such marginal level of reduction.'' See Legislative History, op. cit. 
p. 170. Moreover, the inquiry does not require the Agency to quantify 
benefits in monetary terms. See, for example, American Iron and Steel 
Institute v. EPA, 526 F.2d 1027 (3rd Cir., 1975). For the BPT cost-
reasonableness assessment, EPA used the total pounds of COD removed for 
the General Metals, Metal Finishing Job Shops, Non-Chromium Anodizing, 
Steel Forming and Finishing, and Oily Wastes, and Railroad Line 
Maintenance subcategories because this parameter best represented the 
pollutant removals without counting removals of individual pollutants 
more than once. EPA used O&G for the cost-reasonableness assessment for 
the Shipbuilding Dry Dock subcategories because it best represented the 
pollutant removals for these subcategories without counting removals of 
individual pollutants more than once.
    In balancing costs against the benefits of effluent reduction, EPA 
considers the volume and nature of expected discharges after 
application of BPT, the general environmental effects of pollutants, 
and the cost and economic impacts of the required level of pollution 
control. In past effluent limitations guidelines and standards, BPT 
cost-reasonableness has ranged from $0.94/lb-removed to $34.34/lb-
removed in 1996 dollars. In developing guidelines, the Act does not 
require or permit consideration of water quality problems attributable 
to particular point sources, or water quality improvements in 
particular bodies of water. Therefore, EPA has not considered these 
factors in developing the limitations being proposed today. See 
Weyerhaeuser Company v. Costle, 590 F. 2d 1011 (D.C. Cir. 1978).
    Table IX-1 below summarizes the pounds of pollutants removed for 
direct dischargers, and Table IX-2 summarizes the costs, costs per 
pound removed, and economic impacts for direct dischargers associated 
with each of the proposed options by subcategory. (See Section XII for 
summary tables for indirect dischargers.)

                       Table IX-1.--Pounds of Pollutants Removed by the Proposed BPT Option for Direct Dischargers by Subcategory
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        Priority and      Priortiy and
 Subcategory \1\  (number of                        TSS  (lbs         O&G  (lbs         COD  (lbs      nonconventional   nonconventional   Cyanide  (lbs
         facilities)          Selected  option     removed/yr)       removed/yr)       removed/yr)       metals (lbs     organics  (lbs     removed/yr)
                                                                                                         removed/yr)       removed/yr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
General Metals (3,794)......  Option 2........  10.1 million....  7.8 million.....  181 million.....  4 million.......  5 million.......         184,000
Metal Finishing Job Shops     Option 2........  13,000..........  14,400..........  232,000.........  34,000..........  4,600...........           5,700
 (15) \2\.

[[Page 452]]


Printed Wiring Boards (11)    Option 2........  51,000..........  238,000.........  1.3 million.....  172,000.........  22,000..........           1,400
 \2\.
Steel Forming and Finishing   Option 2........  884,000.........  101,000.........  4.5 million.....  387,000.........  76,000..........           1,100
 (43).
Oily Waste (911)............  Option 6........  349,000.........  885,000.........  5.1 million.....  81,000..........  127,000.........              10
Railroad Line Maintenance     Option 10.......  9,000...........  47,400..........  59,000..........  1,000...........  78..............               0
 (34).
Shipbuilding Dry Dock (6)...  Option 10.......  650.............  8.5 million.....  0...............  1,400...........  700.............              0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ EPA did not identify any direct discharging facilities in the Non-Chromium Anodizing subcategory; therefore, there are no estimated removals. See
  Section IX.C.
\2\ Although EPA is not revising limits for TSS and O&G for these two subcategories, removals are reported based on incidental removals for the proposed
  MP&M Option 2 technology for BPT control of toxic and nonconventional pollutants.

    EPA notes that the pounds removed presented in Table IX-1 may 
differ from the pounds removed presented in the Economic Analysis 
section (Section XVI). This difference is a result of the fact that 
when performing certain economic analyses (e.g., cost-effectiveness), 
the Agency does not include facilities (or the associated pollutant 
loadings and removals) that closed at the baseline (i.e., EPA predicted 
that these facilities would close prior to the implementation of the 
MP&M rule). Table IX-1 above estimates that annual pounds removed by 
the selected option for all of the direct discharging facilities in 
EPA's questionnaire data base that discharged wastewater at the time 
the data were collected.

     Table IX-2.--Annualized Costs and Economic Impacts of the Proposed BPT Option for Direct Dischargers by
                                                   Subcategory
----------------------------------------------------------------------------------------------------------------
                                                                                     Economic
                                                                                      impacts
                                                                                     (facility     BPT cost per
                                                           Annualized compliance   closures) of   pound  removed
    Subcategory \1\  (number of        Selected option       costs for selected      selected      \2\ (1996 $/
            facilities)                                       option  ($1996)         option      pound removed)
                                                                                    (Percent of
                                                                                     regulated
                                                                                   subcategory)
----------------------------------------------------------------------------------------------------------------
General Metals (3,794)............  Option 2.............  230 million..........         20 (1%)            1.22
Metal Finishing Job Shops (15)....  Option 2.............  1.3 million..........               0            5.60
Printed Wiring Boards (11)........  Option 2.............  2.5 million..........               0            1.92
Steel Forming and Finishing (43)..  Option 2.............  29.3 million.........               0            6.51
Oily Waste (911)..................  Option 6.............  11.2 million.........               0            2.18
Railroad Line Maintenance (34)....  Option 10............  1.18 million.........               0           20.00
Shipbuilding Dry Dock (6).........  Option 10............  2.15 million.........               0           0.25
----------------------------------------------------------------------------------------------------------------
\1\ EPA did not identify any direct discharging facilities in the Non-Chromium Anodizing subcategory; therefore,
  there are no estimated costs. See Section IX.C for estimates based on a model facility.
\2\ EPA based the pounds used in calculating the BPT cost reasonableness on the COD removals only (shown in
  Table IX-1) for each subcategory, except for the use of oil and grease removals only (shown in Table IX-1) for
  the shipbuilding dry dock subcategory.

A. General Metals Subcategory

1. Need for BPT Regulation
    EPA describes the General Metals subcategory in Section VI.C.1 of 
this preamble. The Agency estimates that there are approximately 3,800 
direct discharging facilities in the General Metals subcategory. EPA 
estimates that the direct discharging facilities in the General Metals 
subcategory currently discharge substantial quantities of pollutants 
into the surface waters of the United States, including 8.2 million 
pounds per year of oil and grease, 10.9 million pounds per year of 
total suspended solids, 187 million pounds of COD, 5.2 million pounds 
per year of priority and nonconventional metal pollutants, 5.2 million 
pounds of priority and nonconventional organic pollutants, and 187,000 
pounds per year of cyanide. As a result of the quantity of pollutants 
currently discharged directly to the nation's waters by General Metals 
facilities, EPA determined that there was a need for BPT regulation for 
this subcategory.
2. Selected BPT Option
    Facilities in the General Metals subcategory generally perform unit 
operations such as cleaning, etching, electroplating, electroless 
plating, and conversion coating that produce metal-bearing wastewater. 
In addition, some of these facilities also perform machining and 
grinding, impact deformation, and surface preparation operations that 
generate oily wastewater. Therefore, EPA considered technology options 
1 through 4 for this subcategory because technologies included in these 
options treat both oily wastewater as well as metal-bearing wastewater. 
As explained above, EPA only discusses Options 2 and 4 in detail in 
this preamble since these options costed less and removed more 
pollutant than Options 1 and 3 (respectively). See Section VIII.A.1 for 
a discussion of technology options.
    The Agency is proposing Option 2 as the basis for the new BPT 
regulation for the General Metals subcategory. EPA's decision to 
propose BPT limitations based on Option 2 treatment reflects primarily 
two factors: (1) The degree of effluent reductions attainable, and (2) 
the total cost of the proposed treatment technologies in relation to 
the effluent reductions achieved. No basis could be found for 
identifying different BPT limitations based on age, size, process or 
other engineering factors. Neither the age nor the size of a facility 
in the General Metals subcategory will directly

[[Page 453]]

affect the treatability of MP&M process wastewater. For facilities in 
this subcategory, the most pertinent factors for establishing the 
limitations are costs of treatment and the level of effluent reductions 
obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 2, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of COD removed. EPA 
estimates that implementation of Option 2 will cost $1.22 per pound of 
COD removed (1996 $). The Agency has concluded that the costs of BPT 
Option 2 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 2 represents the average of the 
best performing facilities due to the prevalence of chemical 
precipitation followed by sedimentation in this subcategory. 
Approximately 22 percent of the direct discharging facilities in the 
General Metals subcategory employ chemical precipitation followed by a 
clarifier (Option 2) while less than 1 percent employ microfiltration 
after chemical precipitation (Option 4).
    Based on the available data base, Option 4 on an annual basis only 
removes an additional 66,000 pounds of TSS, 12,300 pounds of O&G, 
15,000 pounds of priority metals, and 880,000 pounds of nonconventional 
metals, while removing 324,000 pounds less COD and 31,000 pounds less 
priority and nonconventional organic pollutants than Option 2. Although 
there is a large amount of additional removals of TSS and 
nonconventional metals for Option 4 when considered across the entire 
population (3,800 facilities), the Agency determined that these 
additional removals were not significant when considered on a per 
facility basis. In addition, Option 4's annualized cost is $52 million 
more than Option 2. EPA concluded that the lack of significant 
additional pollutant removals per facility achieved by Option 4 (and 
the fact that it removes less COD and organic pollutants) support the 
selection of Option 2 as the BPT technology basis.
3. Calculation of BPT Limitations for the General Metals Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. In 
general, the Agency calculated BPT limitations for this subcategory 
using data from General Metals facilities employing Option 2 
technology. For cyanide limitations, EPA used data from all 
subcategories where cyanide destruction systems were sampled. If data 
was not sufficient for developing BPT limitations for an individual 
pollutant in this subcategory, the Agency transferred data from another 
subcategory (see the Technical Development Document for a more detailed 
discussion). See the proposed rule Sec. 438.12 following this preamble 
for a list of the proposed BPT limitations for the General Metals 
Subcategory. (See Section XXI.C for a discussion of monitoring 
flexibility.) The Statistical Development Document contains detailed 
information on which facilities EPA used in calculating the proposed 
BPT limitations.

B. Metal Finishing Job Shops Subcategory

1. Need for BPT Regulation
    EPA describes the Metal Finishing Job Shops subcategory in Section 
VI.C.2 of this preamble. The Agency estimates that there are 
approximately 15 direct discharging facilities in the Metal Finishing 
Job Shops subcategory. EPA has previously promulgated BPT and BAT 
limitations for all of the facilities in this subcategory at 40 CFR 
part 413 (Electroplating Pretreatment Standards) and at 40 CFR part 433 
(Metal Finishing Effluent Limitations Guidelines and Pretreatment 
Standards). However, EPA developed the existing regulations applicable 
to the facilities in the Metal Finishing Job Shops subcategory 
approximately 20 years ago, and since that time, advances in 
electroplating and metal finishing processes, water conservation, 
pollution prevention, and wastewater treatment have occurred. EPA is 
proposing new BPT effluent limitations guidelines for this subcategory.
    EPA estimates that direct discharging facilities in the Metal 
Finishing Job Shops subcategory currently discharge substantial 
quantities of pollutants into the surface waters of the United States, 
including 17,900 pounds per year of oil and grease, 20,500 pounds per 
year of TSS, 287,400 pounds per year of COD, 44,000 pounds per year of 
priority and nonconventional metal pollutants, 6,000 pounds per year of 
priority and nonconventional organic pollutants, and 6,000 pounds per 
year of cyanide. As a result of the quantity of pollutants currently 
discharged directly to the nation's waters by metal finishing job shop 
facilities, EPA determined that there was a need for BPT regulation for 
this subcategory.
2. Selected BPT Option
    Facilities in the Metal Finishing Job Shops subcategory generally 
perform unit operations such as cleaning, etching, electroplating, 
electroless plating, passivating, and conversion coating that produce 
metal-bearing wastewater. In addition, some of these facilities also 
perform machining and grinding, impact deformation, and surface 
preparation operations that generate oily wastewater. Therefore, EPA 
considered technology options 1 through 4 for this subcategory because 
technologies included in these options treat both oily wastewater as 
well as metal-bearing wastewater. As explained above, EPA only 
discusses Options 2 and 4 in detail in this preamble since these 
options costed less and removed more pollutant than Options 1 and 3, 
respectively.
    The Agency is proposing Option 2 as the basis for BPT regulation 
for the Metal Finishing Job Shops subcategory. The new BPT limitations 
incorporate more stringent effluent requirements for priority metals, 
nonconventional pollutants, cyanide, and organic pollutants (by way of 
an indicator parameter) as compared to the limitations contained in 40 
CFR 433.13. EPA has included the conventional pollutants, TSS and oil 
and grease, in the new BPT regulation for this subcategory at the same 
level as 40 CFR 433.13. EPA's decision to propose BPT limitations based 
on Option 2 treatment reflects primarily two factors: (1) The degree of 
effluent reductions attainable and (2) the total cost of the proposed 
treatment technologies in relation to the effluent reductions achieved. 
No basis could be found for identifying different BPT limitations based 
on age, size, process or other engineering factors. Neither the age nor 
the size of a facility in the Metal Finishing Job Shop subcategory will 
directly affect the treatability of MP&M process wastewater. For 
facilities in this subcategory, the most pertinent factors for 
establishing the limitations are costs of treatment and the level of 
effluent reductions obtainable. EPA based its decision not to revise 
the conventional pollutant limitations on the use of the alternate 
organics control parameters (i.e., TOC or TOP) and the small additional 
removals of TSS obtainable after the incidental removal due to control 
of the metals.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 2, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of COD removed. EPA 
estimates that implementation of Option 2 will cost $5.60 per pound of 
COD removed (1996$). The Agency has concluded that the costs of BPT 
Option 2 are achievable and are reasonable as compared to the removals 
achieved by this option.

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    The technology proposed in Option 2 represents the average of the 
best performing facilities due to the prevalence of chemical 
precipitation followed by sedimentation in the subcategory. The Agency 
estimates that 100 percent of the direct discharging facilities in the 
Metal Finishing Job Shops subcategory employ chemical precipitation 
followed by a clarifier (Option 2) while no facilities employ 
microfiltration after chemical precipitation (Option 4). Because no 
facilities in this subcategory employ microfiltration after chemical 
precipitation for solids separation, the Agency concluded that Option 4 
does not represent the average of the best treatment.
    Based on the available data base, Option 4 on an annual basis only 
removes an additional 6,900 pounds of priority and nonconventional 
metals, while removing 1,500 pounds less COD, and 600 pounds less 
priority and nonconventional organic pollutants than Option 2. EPA 
concluded that the lack of significant overall additional pollutant 
removals achieved by Option 4 (and the fact that it removes less COD, 
and organic pollutants) support the selection of Option 2 as the BPT 
technology basis.
3. Calculation of BPT Limitations for the Metal Finishing Job Shops 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. In 
general, EPA calculated the new BPT limitations for this subcategory 
using data from facilities in the Metal Finishing Job Shops subcategory 
employing Option 2 technology. As discussed above, EPA did not 
calculate new limitations for TSS or oil and grease for this 
subcategory. Instead, EPA set them at the same level as in the Metal 
Finishing effluent guidelines (40 CFR 433.13). For cyanide limitations, 
EPA used data from all subcategories where cyanide destruction systems 
were sampled. If data was not sufficient for developing BPT limitations 
for an individual pollutant in this subcategory, the Agency transferred 
data from another subcategory (see the Technical Development Document 
for a more detailed discussion). See the proposed rule Sec. 438.22 
following this preamble for a list of the proposed BPT limitations for 
the Metal Finishing Job Shops subcategory. (See Section XXI.C for a 
discussion of monitoring flexibility.) The Statistical Development 
Document contains detailed information on which facilities EPA used in 
calculating the proposed BPT limitations.

C. Non-Chromium Anodizing Subcategory

1. Need for BPT Regulation
    EPA describes the Non-Chromium Anodizing subcategory in Section 
VI.C.3 of this preamble. EPA's survey of the MP&M industry did not 
identify any non-chromium anodizing facilities discharging directly to 
surface waters. All of the non-chromium anodizing facilities in EPA's 
data base are either indirect or zero dischargers. EPA consequently 
could not evaluate any treatment systems in place at direct discharging 
non-chromium anodizing facilities for establishing BPT limitations. 
Therefore, EPA relied on technology transfer based on information and 
data from indirect discharging facilities in the Non-Chromium Anodizing 
subcategory. The Agency concluded that the technology in place at some 
indirect discharging non-chromium anodizers is appropriate to use as 
the basis for regulation of direct dischargers because the pollutant 
profile of the wastewater generated at non-chromium anodizers 
discharging directly would be similar in character to that from 
indirect discharging non-chromium anodizers and the model technologies 
in place at indirect dischargers are effective in treating the 
conventional pollutants that are generally not regulated in 
pretreatment standards.
    EPA has previously promulgated BPT and BAT limitations for all of 
the facilities in this subcategory at 40 CFR part 433 (Metal Finishing 
Effluent Limitations Guidelines and Pretreatment Standards). However, 
EPA developed the regulations applicable to this subcategory 
approximately 20 years ago, and since that time, advances in anodizing 
processes, water conservation, pollution prevention, and wastewater 
treatment have occurred. EPA is proposing to set new BPT effluent 
limitations guidelines for this subcategory for metals, but is not 
revising the limitations for conventional pollutants (TSS and oil and 
grease). EPA based its decision not to revise the limitations for 
conventional pollutants on the small additional removals attainable 
after the incidental removal due to control of the metals.
    The current regulations in 40 CFR part 433 require non-chromium 
anodizing facilities to meet effluent limitations for 7 metal 
pollutants. EPA's data show that these seven metals are present only in 
very small quantities in the current discharges at non-chromium 
anodizing facilities. Under the Metal Finishing effluent guidelines, 
EPA did not establish a BPT limit for aluminum, the metal found in the 
largest quantity in non-chromium anodizers wastewater. The Agency has 
determined that direct discharging facilities in the Non-Chromium 
Anodizing subcategory should have a limit for aluminum and thus is 
proposing to replace BPT in 40 CFR part 433 with new MP&M effluent 
limitations that more appropriately reflect the pollutants found in 
non-chromium anodizing wastewater. EPA notes that the Agency expects a 
reduction in monitoring burden associated with this revision for direct 
discharging non-chromium anodizing facilities.
2. Selected BPT Option
    Facilities in the Non-Chromium Anodizing subcategory generally 
perform unit operations such as cleaning, etching, and anodizing of 
aluminum, that produce metal-bearing wastewater. The majority of the 
metal found in anodizing wastewater is aluminum. In addition, some of 
these facilities also perform machining and grinding, impact 
deformation, and surface preparation operations that generate oily 
wastewater. Therefore, EPA considered technology options 1 through 4 
for this subcategory because technologies included in these options 
treat both oily wastewater as well as metal-bearing wastewater. As 
explained above, EPA only discusses Options 2 and 4 in detail in this 
preamble since these options costed less and removed more pollutant 
than Options 1 and 3 (respectively).
    The Agency is proposing Option 2 as the basis for BPT regulation 
for the Non-Chromium Anodizing subcategory. Although EPA did not 
identify any existing non-chromium anodizers, EPA estimated the cost of 
treatment and pollutant removal for a median-sized direct discharging 
facility with a wastewater flow of 6.25 MGY, based on the 
characteristics of a similarly sized indirect discharging non-chromium 
anodizer facility. Because direct dischargers are more likely to have 
treatment in place, EPA provided the model facility with treatment in 
place equivalent to Option 1. Therefore at the model direct discharging 
non-chromium anodizing facility, EPA estimates that implementation of 
Option 2 will cost $0.83 per pound COD removed (1996$), and has found 
that cost to be reasonable. EPA estimates that Option 2 would remove 
25,700 pounds of pollutants per median-sized facility per year 
(including 9,200 pounds of TSS as incidental removals based on the 
control of metals and 1,240 pounds of aluminum).

[[Page 455]]

    Additionally, because solids separation by microfiltration is not 
used by any non-chromium anodizer facilities, the Agency concluded that 
Option 4 does not represent best practicable control technology for 
this subcategory.
3. Calculation of BPT Limitations for the Non-Chromium Anodizing 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. Because 
EPA's survey did not identify any direct dischargers in this 
subcategory, EPA used data from indirect discharging facilities to 
develop the BPT limitations. The Agency identified two indirect 
discharging facilities in this subcategory that achieved very good 
pollutant reductions (including, on average, 96 percent reduction of 
aluminum and incidental removals of 95 percent for TSS). Therefore, EPA 
determined that the data from these facilities were appropriate for the 
development of BPT limitations. If data was not sufficient for 
developing BPT limitations for an individual pollutant in this 
subcategory, the Agency transferred data from another subcategory (see 
the Technical Development Document for a more detailed discussion). In 
the case of TSS and oil and grease, EPA used the limitations in 40 CFR 
part 433.13. See the proposed rule Sec. 438.32 following this preamble 
for a list of the proposed BPT limitations for the Non-Chromium 
Anodizers Subcategory. (See Section XXI.C for a discussion of 
monitoring flexibility.) The Statistical Development Document contains 
detailed information on which facilities EPA used in calculating the 
proposed BPT limitations.

D. Printed Wiring Board Subcategory

1. Need for BPT Regulation
    EPA describes the Printed Wiring Board subcategory in Section 
VI.C.4 of this preamble. The Agency estimates that there are 
approximately 11 direct discharging facilities in this subcategory. EPA 
has previously promulgated BPT and BAT limitations for all of the 
facilities in this subcategory at 40 CFR part 433 (Metal Finishing 
Effluent Limitations Guidelines and Pretreatment Standards). However, 
EPA developed the regulations applicable to this subcategory 
approximately 20 years ago, and since that time, advances in printed 
wiring board manufacturing processes, water conservation practices, 
pollution prevention techniques, and wastewater treatment have 
occurred. EPA is proposing to set new BPT effluent limitations 
guidelines for this subcategory.
    EPA estimates that direct discharging facilities in the Printed 
Wiring Board subcategory currently discharge substantial quantities of 
pollutants into the surface waters of the United States, including 
262,000 pounds per year of oil and grease, 100,000 pounds per year of 
total suspended solids, 1.7 million pounds per year of COD, 242,000 
pounds per year of priority and nonconventional metal pollutants, 
35,000 pounds per year of priority and nonconventional organic 
pollutants, and 1,600 pounds per year of cyanide. As a result of the 
quantity of pollutant currently discharged directly to the nation's 
waters by printed wiring board facilities, EPA determined that there 
was a need for BPT regulation for this subcategory.
2. Selected BPT Option
    Facilities in the Printed Wiring Board subcategory generally 
perform unit operations such as cleaning, etching, masking, 
electroplating, electroless plating, applying, developing and stripping 
of photoresist, and tin/lead soldering that produce metal-bearing and 
organic-bearing wastewater. Therefore, EPA considered technology 
options 1 through 4 for this subcategory. As explained above, EPA only 
discusses Options 2 and 4 in detail in this preamble since these 
options costed less and removed more pollutant than Options 1 and 3 
(respectively).
    The Agency is proposing Option 2 as the basis for BPT regulation 
for the Printed Wiring Board subcategory. The new BPT limitations 
incorporate more stringent effluent requirements for priority metals, 
nonconventional pollutants, cyanide, and organic pollutants (by way of 
an indicator parameter) as compared to the limitations contained in 40 
CFR part 433.13. EPA has included the conventional pollutants, TSS and 
oil and grease, in the new BPT regulation for this subcategory at the 
same level as 40 CFR part 433.13. Removals for these pollutants are 
incidental removals based on the increased control of metals and 
organic pollutants (by way of an indicator parameter) by the proposed 
BPT technology options. EPA's decision to propose BPT limitations based 
Option 2 treatment for priority metals, nonconventional pollutants, 
cyanide and organic pollutants reflects primarily two factors: (1) The 
degree of effluent reductions attainable and (2) the total cost of the 
proposed treatment technologies in relation to the effluent reductions 
achieved. No basis could be found for identifying different BPT 
limitations based on age, size, process or other engineering factors. 
Neither the age nor the size of a facility in the Printed Wiring Board 
subcategory will directly affect the treatability of MP&M process 
wastewater. For facilities in this subcategory, the most pertinent 
factors for establishing the limitations are costs of treatment and the 
level of effluent reductions obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 2, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of COD removed. EPA 
estimates that implementation of Option 2 will cost $1.92 per pound of 
COD removed (1996$). The Agency has concluded that the costs of BPT 
Option 2 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 2 represents the average of the 
best performing facilities due to the prevalence of chemical 
precipitation followed by sedimentation in this subcategory. The Agency 
estimates that 100 percent of the direct discharging facilities in the 
Printed Wiring Board subcategory employ chemical precipitation and 
sedimentation treatment (Option 2); however, the Agency did identify 
indirect dischargers in this subcategory with Option 4 technology in 
place. In fact, EPA collected wastewater treatment samples at one 
indirect discharging printed wiring board manufacturing facility that 
employed Option 4 technology.
    Based on the available data base, Option 4 on an annual basis only 
removes an additional 48,000 pounds of priority and nonconventional 
metals, while removing 9,000 less pounds of COD, and 250 less pounds of 
priority and nonconventional organic pollutants than Option 2. In 
addition, Option 4's annualized cost is $2 million more than Option 2. 
EPA concluded that the lack of significant overall additional pollutant 
removals achieved by Option 4 (and the fact that it removes less COD, 
and organic pollutants) support the selection of Option 2 as the BPT 
technology basis.
3. Calculation of BPT Limitations for the Printed Wiring Board 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. In 
general, EPA calculated the new BPT limitations for this subcategory 
using data from facilities in the Printed Wiring Board subcategory 
employing Option 2 technology. As discussed above, EPA

[[Page 456]]

did not calculate new limitations for TSS or oil and grease for this 
subcategory. Instead, EPA set them at the same level as in the Metal 
Finishing effluent guidelines (40 CFR part 433.13). For cyanide 
limitations, EPA used data from all subcategories where cyanide 
destruction systems were sampled. If data was not sufficient for 
developing BPT limitations for an individual pollutant in this 
subcategory, the Agency transferred data from another subcategory (see 
the Technical Development Document for a more detailed discussion). See 
the proposed rule Sec. 438.42 following this preamble for a list of the 
proposed BPT limitations for the Printed Wiring Board subcategory. (See 
Section XXI.C. for a discussion of monitoring flexibility.) The 
Statistical Development Document contains detailed information on which 
facilities EPA used in calculating the proposed BPT limitations.

E. Steel Forming and Finishing Subcategory

1. Need for BPT Regulation
    EPA describes the Steel Forming & Finishing subcategory in Section 
VI.C.5 of this preamble. The Agency estimates that there are 
approximately 43 direct discharging facilities in this subcategory. EPA 
has previously promulgated BPT and BAT limitations for all of the 
facilities in this subcategory at 40 CFR part 420 (Iron and Steel 
Manufacturing Effluent Limitations Guidelines and Pretreatment 
Standards). However, EPA developed the regulations applicable to this 
subcategory approximately 20 years ago, and since that time, changes in 
the industry, particularly in growth of the number of facilities 
conducting steel forming and finishing operations without the presence 
of the typical steel manufacturing processes, and changes in water 
conservation practices, pollution prevention techniques, and wastewater 
treatment have occurred. In addition, the operations covered by this 
proposed rule are segments of the forming and finishing subcategories 
in 40 CFR part 420. The proposed MP&M subcategory is comprised of 
limitations and standards based on specific forming and finishing 
operations only.
    EPA estimates that direct discharging facilities in the new Steel 
Forming & Finishing subcategory currently discharge substantial 
quantities of pollutants into the surface waters of the United States, 
including 195,000 pounds per year of oil and grease, 1.08 million 
pounds per year of total suspended solids, 6 million pounds per year of 
COD, 771,000 pounds per year of priority and nonconventional metal 
pollutants, 168,000 pounds per year of priority and nonconventional 
organic pollutants, and 2,300 pounds per year of cyanide. As a result 
of the quantity of pollutant currently discharged directly to the 
nation's waters by steel forming & finishing facilities, EPA determined 
that there was a need for BPT regulation for this subcategory. In a 
separate notice, EPA is proposing to revise other subcategories in the 
Iron and Steel Manufacturing effluent guidelines.
2. Selected BPT Option
    Facilities in the proposed MP&M Steel Forming & Finishing 
subcategory generally perform unit operations such as acid pickling, 
annealing, conversion coating (e.g., zinc phosphate, copper sulfate), 
hot dip coating, electroplating, heat treatment, welding, and drawing 
of steel bar, rod, and wire that produce metal-bearing and oil-bearing 
wastewater. Therefore, EPA considered technology options 1 through 4 
for this subcategory. As explained above, EPA only discusses Options 2 
and 4 in detail in this preamble since these options costed less and 
removed more pollutant than Options 1 and 3 (respectively).
    The Agency is proposing Option 2 as the basis for the new BPT 
regulation for the Steel Forming & Finishing subcategory. EPA's 
decision to propose BPT limitations based on Option 2 treatment 
reflects primarily two factors: (1) the degree of effluent reductions 
attainable and (2) the total cost of the proposed treatment 
technologies in relation to the effluent reductions achieved. No basis 
could be found for identifying different BPT limitations based on age, 
size, process or other engineering factors. Neither the age nor the 
size of a facility in the Steel Forming and Finishing subcategory will 
directly affect the treatability of MP&M process wastewater. For 
facilities in this subcategory, the most pertinent factors for 
establishing the limitations are costs of treatment and the level of 
effluent reductions obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 2, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of COD removed. EPA 
estimates that implementation of Option 2 will cost $6.51 per pound of 
COD removed ($1996). The Agency has concluded that the costs of BPT 
Option 2 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 2 represents the average of the 
best performing facilities due to the prevalence of chemical 
precipitation followed by sedimentation in this subcategory. The Agency 
estimates that 64 percent of the direct discharging facilities in this 
subcategory employ chemical precipitation followed by sedimentation 
(Option 2). Because no facilities in this subcategory employ 
microfiltration after chemical precipitation for solids separation, the 
Agency concluded that Option 4 does not represent best practicable 
control technology.
3. Calculation of BPT Limitations for the Steel Forming & Finishing 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. In 
general, EPA calculated BPT limitations for this subcategory using data 
transferred from facilities employing Option 2 technology in the 
General Metals subcategory. However, EPA determined that mass-based 
limitations (rather than concentration-based limitations developed for 
the General Metals subcategory) are more appropriate for this 
subcategory. Facilities in this subcategory keep close track of their 
production on a mass basis primarily because of their prior regulation 
under the mass-based Iron & Steel Manufacturing effluent guidelines. 
Furthermore, EPA determined that mass-based limitations are appropriate 
for this subcategory due to the uniform nature of the products produced 
(wire, rod, bar, pipe, and tube). The uniform nature of the products 
produced by this industry makes for an easier conversion from 
concentration-based to mass-based limitations. One of the primary 
reasons that EPA is not requiring mass-based limitations for other 
subcategories is the fact that most MP&M facilities do not collect 
production information on a wastestream-by-wastestream basis, and 
therefore development of mass-based limitations could create a 
significant burden for both the POTW and the MP&M facility. In the case 
of the Steel Forming and Finishing subcategory, EPA is able to use the 
industry's production information to propose production-based 
limitations for the steel forming and finishing subcategory.
    EPA solicits paired treatment system influent and effluent data 
from Steel Forming & Finishing facilities, so that limits may better 
reflect treatment at steel forming and finishing facilities. EPA also 
solicits comment on whether to allow concentration-based limits for 
this subcategory and any rationale for doing so. For cyanide 
limitations, EPA used data from all subcategories where cyanide 
destruction systems were sampled (see the Technical

[[Page 457]]

Development Document for a more detailed discussion). See the proposed 
rule Sec. 438.52 following this preamble for a list of the proposed BPT 
limitations for the Steel Forming & Finishing subcategory. (See Section 
XXI.C for a discussion of monitoring flexibility.) The Statistical 
Development Document contains detailed information on which facilities 
EPA used in calculating the proposed BPT limitations.

F. Oily Wastes Subcategory

1. Need for BPT Regulation
    EPA describes the Oily Wastes subcategory in Section VI.C.6 of this 
preamble. EPA estimates that approximately 900 MP&M direct discharging 
facilities in the Oily Wastes subcategory currently discharge 
substantial quantities of pollutants into the surface waters of the 
United States, including 965,000 pounds per year of oil and grease, 
414,00 pounds per year of total suspended solids, 6.4 million pounds 
per year of COD, 595,000 pounds per year of priority and 
nonconventional metal pollutants, and 135,000 pounds per year of 
priority and nonconventional organic pollutants. As a result of the 
quantity of pollutant currently discharged directly to the nation's 
waters by Oily Waste facilities, EPA determined that there was a need 
for BPT regulation for this subcategory.
2. Selected BPT Option
    Facilities in the Oily Wastes subcategory generally perform unit 
operations such as alkaline cleaning and its associated rinses to 
remove oil and dirt from components, machining and grinding producing 
wastewater containing coolants and lubricants, and dye penetrant and 
magnetic flux testing that produce mainly oil-bearing wastewater (see 
Section VI.C.6 for a list of the unit operations that define the 
applicability of this subcategory). Because of the oily nature of the 
wastewater, EPA considered technology options 5 through 8 for this 
subcategory. (EPA did not consider oily wastewater treatment using DAF 
(Options 9 and 10) because it was not widely used by facilities in this 
subcategory. The Agency analyzed the DAF options for the Railroad Line 
Maintenance and Shipbuilding Dry Dock subcategories only.) As explained 
above, EPA only discusses Options 6 and 8 in detail in this preamble 
since these options costed less and removed more pollutant than Options 
5 and 7 (respectively).
    The Agency is proposing Option 6, oil-water separation by chemical 
emulsion breaking, gravity separation, and oil skimming, as the basis 
for the new BPT regulation for the Oily Wastes subcategory. EPA's 
decision to propose BPT limitations based on Option 6 treatment 
reflects primarily two factors: (1) the degree of effluent reductions 
attainable and (2) the total cost of the proposed treatment 
technologies in relation to the effluent reductions achieved. No basis 
could be found for identifying different BPT limitations based on age, 
size, process or other engineering factors. Neither the age nor the 
size of a facility in the Oily Wastes subcategory will directly affect 
the treatability of MP&M process wastewater. For facilities in this 
subcategory, the most pertinent factors for establishing the 
limitations are costs of treatment and the level of effluent reductions 
obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 6, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of COD removed. EPA 
estimates that implementation of Option 6 will cost $2.18 per pound of 
COD removed (1996$). The Agency has concluded that the costs of BPT 
Option 6 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 6 represents the average of the 
best performing facilities due to the prevalence of chemical emulsion 
breaking and oil-skimming in this subcategory. The Agency estimates 
that 11 percent of the direct discharging facilities in the Oily Wastes 
subcategory perform oil-water separation through chemical emulsion 
breaking (Option 6) while only 4 percent employ ultrafiltration (Option 
8).
    Based on the available data base, Option 8 on an annual basis only 
removes an additional 19,000 pounds of TSS, 56,600 pounds of O&G, while 
removing 1.42 million less pounds of COD, 12,000 less pounds of 
priority and nonconventional metals, and 2,400 less pounds of priority 
and nonconventional organic pollutants than Option 6. In addition, 
Option 8's annualized cost is $43 million more than Option 6. EPA 
concluded that the lack of significant overall additional pollutant 
removals achieved by Option 8 do not justify its use as a basis for BPT 
for this subcategory.
3. Calculation of BPT Limitations for the Oily Wastes subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. EPA 
calculated BPT limitations for this subcategory using data from 
facilities in the Oily Wastes subcategory employing Option 6 
technology. See the proposed rule Sec. 438.62 following this preamble 
for a list of the proposed BPT limitations for the Oily Wastes 
subcategory. (See Section XXI.C for a discussion of monitoring 
flexibility.) The Statistical Development Document contains detailed 
information on which facilities EPA used in calculating the proposed 
BPT limitations.

G. Railroad Line Maintenance Subcategory

1. Need for BPT Regulation
    EPA describes the Railroad Line Maintenance subcategory in Section 
VI.C.7 of this preamble. The Agency estimates that there are 
approximately 34 direct discharging facilities in this subcategory. EPA 
determined that BPT limitations for this subcategory were necessary 
because of the oil and grease and potential TSS loads that facilities 
in this subcategory generate. EPA estimates that direct discharging 
facilities in the Railroad Line Maintenance subcategory currently 
discharge substantial quantities of pollutants into the surface waters 
of the United States, including 52,000 pounds per year of oil and 
grease, 170,000 pounds per year of COD, 18,000 pounds per year of total 
suspended solids, 54,000 pounds per year of priority and 
nonconventional metal pollutants, and 1,600 pounds per year of priority 
and nonconventional organic pollutants. As a result of the quantity of 
pollutant currently discharged directly to the nation's waters by 
Railroad Line Maintenance facilities, EPA determined that there was a 
need for BPT regulation for this subcategory.
2. Selected BPT Option
    Facilities in the Railroad Line Maintenance subcategory generally 
perform unit operations that produce mainly oil-bearing wastewater such 
as alkaline cleaning and its associated rinses to remove oil and dirt 
from components, and machining and grinding which use coolants and 
lubricants. Because of the oily nature of the wastewater, EPA 
considered technology options 7 through 10 for this subcategory. (EPA 
did not consider oily wastewater treatment using oil-water separation 
through emulsion breaking (Options 5 and 6) for this subcategory 
because a large number of railroad line maintenance facilities 
currently use DAF (Options 9 and 10)). As explained above, EPA only 
discusses Options 8 and 10 in detail in this preamble since these 
options costed less and removed

[[Page 458]]

more pollutant than Options 7 and 9 (respectively).
    The Agency is proposing Option 10, oil-water separation by DAF, as 
the basis for the new BPT regulation for the Railroad Line Maintenance 
subcategory. EPA's decision to propose BPT limitations based on Option 
10 treatment reflects primarily two factors: (1) the degree of effluent 
reductions attainable and (2) the total cost of the proposed treatment 
technologies in relation to the effluent reductions achieved. No basis 
could be found for identifying different BPT limitations based on age, 
size, process or other engineering factors. Neither the age nor the 
size of a facility in the Railroad Line Maintenance subcategory will 
directly affect the treatability of MP&M process wastewater. For 
facilities in this subcategory, the most pertinent factors for 
establishing the limitations are costs of treatment and the level of 
effluent reductions obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 10, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of O&G removed. EPA 
estimates that implementation of Option 10 will cost $20.00 per pound 
of COD removed (1996$). The Agency has concluded that the costs of BPT 
Option 10 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 10 represents the average of the 
best performing facilities due to the prevalence of DAF in this 
subcategory. The Agency estimates that 91 percent of the direct 
discharging facilities in the Railroad Line Maintenance subcategory 
employ DAF (Option 10) while no facilities employ ultrafiltration 
(Option 8). Because no facilities in this subcategory employ 
ultrafiltration for removal of O&G, the Agency concluded that Option 8 
does not represent best practicable control technology.
3. Calculation of BPT Limitations for the Railroad Line Maintenance 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. EPA 
calculated BPT limitations for this subcategory using data from 
facilities in the Railroad Line Maintenance subcategory employing 
Option 10 technology. In cases where data from the Railroad Line 
Maintenance subcategory was not sufficient for a particular pollutant, 
the Agency transferred effluent data from facilities in the 
Shipbuilding Dry Dock subcategory in order to develop a proposed BPT 
limitation (see the Technical Development Document for a more detailed 
discussion). See the proposed rule Sec. 438.72 following this preamble 
for a list of the proposed BPT limitations for the Railroad Line 
Maintenance subcategory. (See Section XXI.C for a discussion of 
monitoring flexibility.) The Statistical Development Document contains 
detailed information on which facilities EPA used in calculating the 
proposed BPT limitations.

H. Shipbuilding Dry Dock Subcategory

1. Need for BPT Regulation
    EPA describes the Shipbuilding Dry Dock subcategory in Section 
VI.C.8 of this preamble. The Agency estimates that there are six direct 
discharging facilities in this subcategory. The Agency notes that many 
shipbuilders operate multiple dry docks (or similar structures) and 
that this is the number of estimated facilities (not dry docks) that 
discharge MP&M process wastewater from dry docks (and similar 
structures). EPA determined that BPT limitations for this subcategory 
were necessary because of the oil and grease and potential TSS loads 
that facilities in this subcategory generate. EPA estimates that direct 
discharging facilities in the Shipbuilding Dry Dock subcategory 
currently discharge substantial quantities of pollutants into the 
surface waters of the United States, including 8.5 million pounds per 
year of oil and grease, 18,400 pounds per year of total suspended 
solids, 976,000 pounds per year of COD, 88,500 pounds per year of 
priority and nonconventional metal pollutants, and 6,000 pounds per 
year of priority and nonconventional organic pollutants. As a result of 
the quantity of pollutant currently discharged directly to the nation's 
waters by Shipbuilding Dry Dock facilities, EPA determined that there 
was a need for BPT regulation for this subcategory.
2. Selected BPT Option
    Facilities in the Shipbuilding Dry Dock subcategory generally 
perform unit operations that produce mainly oil-bearing wastewater such 
as abrasive blasting, hydroblasting, painting, welding, corrosion 
preventive coating, floor cleaning, aqueous degreasing, and testing 
(e.g., hydrostatic testing). Because of the oily nature of the 
wastewater, EPA considered technology options 7 through 10 for this 
subcategory. (EPA did not consider oily wastewater treatment using oil-
water separation through chemical emulsion breaking (Options 5 and 6) 
for this subcategory because all of the shipbuilding dry dock 
facilities in EPA's database currently use DAF (Options 9 and 10)). As 
explained above, EPA only discusses Options 8 and 10 in detail in this 
preamble since these options costed less and removed more pollutant 
than Options 7 and 9 (respectively).
    The Agency is proposing Option 10, oil-water separation by DAF, as 
the basis for the new BPT regulation for the Shipbuilding Dry Dock 
subcategory. EPA's decision to propose BPT limitations based Option 10 
treatment reflects primarily two factors: (1) The degree of effluent 
reductions attainable and (2) the total cost of the proposed treatment 
technologies in relation to the effluent reductions achieved. No basis 
could be found for identifying different BPT limitations based on age, 
size, process or other engineering factors. Neither the age nor the 
size of a facility in the Shipbuilding Dry Dock subcategory will 
directly affect the treatability of MP&M process wastewater. For 
facilities in this subcategory, the most pertinent factors for 
establishing the limitations are costs of treatment and the level of 
effluent reductions obtainable.
    In Table IX-1 above, EPA presents the annual pollutant removals for 
direct dischargers for Option 10, and in Table IX-2 above, it presents 
the cost per pound removed using only the pounds of O&G removed. EPA 
estimates that implementation of Option 10 will cost $0.25 per pound of 
O&G removed (1996$). The Agency has concluded that the costs of BPT 
Option 10 are achievable and are reasonable as compared to the removals 
achieved by this option.
    The technology proposed in Option 10 represents the average of the 
best performing facilities due to the prevalence of DAF in this 
subcategory. According to EPA's database, 100 percent of the direct 
discharging facilities in the Shipbuilding Dry Dock subcategory employ 
DAF (Option 10) while no facilities employ ultrafiltration (Option 8). 
Because no facilities in this subcategory employ ultrafiltration for 
removal of O&G, the Agency concluded that Option 8 does not represent 
best practicable control technology.
3. Calculation of BPT Limitations for the Shipbuilding Dry Dock 
Subcategory
    EPA explained its data editing procedures and statistical 
methodology for calculating BPT limitations in Section VIII.B. EPA 
calculated BPT limitations for this subcategory using data from 
facilities in the Shipbuilding Dry Dock subcategory employing Option 10 
technology. See the proposed rule Sec. 438.82 following this preamble 
for a

[[Page 459]]

list of the proposed BPT limitations for the Shipbuilding Dry Dock 
subcategory. (See Section XXI.C. for a discussion of monitoring 
flexibility.) The Statistical Development Document contains detailed 
information on which facilities EPA used in calculating the proposed 
BPT limitations.

X. Best Conventional Pollutant Control Technology (BCT)

A. July 9, 1986 BCT Methodology

    The BCT methodology, promulgated in 1986 (51 FR 24974), discusses 
the Agency's consideration of costs in establishing BCT effluent 
limitations guidelines. EPA evaluates the reasonableness of BCT 
candidate technologies (those that are technologically feasible) by 
applying a two-part cost test:
    (1) The POTW test; and
    (2) The industry cost-effectiveness test.
    In the POTW test, EPA calculates the cost per pound of conventional 
pollutant removed by industrial dischargers in upgrading from BPT to a 
BCT candidate technology and then compares this cost to the cost per 
pound of conventional pollutant removed in upgrading POTWs from 
secondary treatment. The upgrade cost to industry must be less than the 
POTW benchmark of $0.25 per pound (in 1976 dollars).
    In the industry cost-effectiveness test, the ratio of the 
incremental BPT to BCT cost divided by the BPT cost for the industry 
must be less than 1.29 (i.e., the cost increase must be less than 29 
percent).

B. Discussion of BCT Option for Metal-Bearing Wastewater

    For today's proposed rule, EPA considered whether or not to 
establish BCT effluent limitation guidelines for MP&M sites that would 
attain incremental levels of effluent reduction beyond BPT for TSS. The 
only technology option identified to attain further TSS reduction is 
the addition of multimedia filtration to existing BPT systems. For the 
BCT option, EPA considered the addition of multimedia filtration to the 
BPT technology option for the General Metals, Metal Finishing Job 
Shops, Non-Chromium Anodizing, Printed Wiring Board, and Steel Forming 
and Finishing subcategories (i.e., the metal-bearing subcategories).
    EPA applied the BCT cost test to use of multimedia filtration 
technology as a means to reduce TSS loadings. EPA split the MP&M sites 
into three flow categories: less than 10,000 gallons per year (gpy)); 
10,000 gpy to 1,000,000 gpy; and greater than 1,000,000 gpy. For each 
of these three flow categories, EPA chose a representative site for 
which EPA had estimated the costs of installing the Option 2 
technologies discussed under BPT (See Section IX above). The Agency 
evaluated the costs of installing a polishing multimedia filter to 
remove an estimated additional 35 percent of the TSS discharged after 
chemical precipitation and clarification treatment. This estimated 
removal reflects the reduced TSS concentrations seen when filters are 
used after chemical precipitation and sedimentation in the MP&M 
industry. The cost per pound removed for facilities discharging greater 
than 1 MGY was $13/lb of TSS (in 1976 dollars), the cost per pound 
removed for facilities discharging between 10,000 and 1,000,000 gpy was 
$518/lb and the cost per pound removed for facilities discharging less 
than 10,000 gpy was $1,926/lb of TSS (in 1976 dollars). All of these 
cases individually as well as combined exceed the $0.25/lb (in 1976 
dollars) POTW cost test value. Because these costs exceed the POTW 
benchmark, the first part of the cost test fails; therefore, the second 
part of the test was unnecessary. Therefore, EPA determined that 
multimedia filtration does not pass the cost test for BCT regulations 
development. In light of the above, EPA is proposing to set BCT 
limitations for the General Metals, Metal Finishing Job Shops, Non-
Chromium Anodizing, Printed Wiring Board, and Steel Forming and 
Finishing subcategories equivalent to BPT limitations for their 
respective subcategories.

C. Discussion of BCT Option for Oily Wastewater

    For today's proposed rule, EPA considered whether or not to 
establish BCT effluent limitation guidelines for MP&M facilities that 
would attain incremental levels of effluent reduction beyond BPT for 
O&G. EPA considered the addition of an ultrafilter to existing BPT 
systems (oil-water separation by chemical emulsion breaking, gravity 
separation, and oil skimming) as a viable technology option to attain 
further O&G reduction. EPA considered this BCT option for the Oily 
Wastes, Railroad Line Maintenance, and Shipbuilding Dry Dock 
subcategories.
    EPA applied the BCT cost test to use of ultrafiltration technology 
as a means to reduce O&G loadings. EPA split the MP&M sites into three 
flow categories: less than 10,000 gallons per year (gpy); 10,000 gpy to 
1,000,000 gpy; and greater than 1,000,000 gpy. For each of these three 
flow categories, EPA chose a representative site for which EPA had 
estimated the costs of installing the Option 2 technologies discussed 
under BPT (See Section IX above). The Agency evaluated the costs of 
installing an ultrafilter to remove an estimated additional 36 percent 
of the O&G discharged after oil-water separation by chemical emulsion 
breaking, gravity separation, and oil skimming. This estimated removal 
reflects the reduced O&G concentrations seen when ultrafilters are used 
after chemical emulsion breaking with oil skimming in the MP&M 
industry. The cost per pound removed for facilities discharging greater 
than 1 MGY was $238/lb of O&G (in 1976 dollars), the cost per pound 
removed for facilities discharging between 10,000 and 1,000,000 gpy was 
$2,213/lb, and the cost per pound removed for facilities discharging 
less than 10,000 gpy was $5,031/lb of O&G (in 1976 dollars). All of 
these cases individually as well as combined exceed the $0.25/lb (in 
1976 dollars) POTW cost test value. Because these costs exceed the POTW 
benchmark, the first part of the cost test fails; therefore, the second 
part of the test was unnecessary. Therefore, EPA determined that 
ultrafiltration does not pass the cost test for BCT regulations 
development. In light of the above, EPA is proposing to set BCT 
limitations for the Oily Wastes, Railroad Line Maintenance and 
Shipbuilding Dry Dock subcategories equivalent to BPT limitations for 
their respective subcategories.

XI. Best Available Technology Economically Achievable (BAT)

    EPA considers the following factors in establishing the best 
available technology economically achievable (BAT) level of control: 
the age of process equipment and facilities, the processes employed, 
process changes, the engineering aspects of applying various types of 
control techniques, the costs of applying the control technology, 
economic impacts imposed by the regulation, non-water quality 
environmental impacts such as energy requirements, air pollution and 
solid waste generation, and other such factors as the Administrator 
deems appropriate (section 304(b)(2)(B) of the Act). In general, the 
BAT technology level represents the best existing economically 
achievable performance among plants with shared characteristics. In 
making the determination about economic achievability, the Agency takes 
into consideration factors such as plant closures and product line 
closures. Where existing wastewater treatment performance is uniformly 
inadequate,

[[Page 460]]

BAT technology may be transferred from a different subcategory or 
industrial category. BAT may also include process changes or internal 
plant controls which are not common industry practice.
    EPA considered the same 10 technology options for BAT as it 
discussed under BPT. EPA did not include the application of filters, 
discussed under BPT, as a BAT option. Data collected during sampling at 
MP&M facilities demonstrated very little, if any, additional removal of 
many metal pollutants resulting from the use of filters as compared to 
concentrations of the same metals after the chemical precipitation and 
clarification treatment followed by gravity settling. Thus, although 
filtration is demonstrated to be effective in achieving additional 
removals of suspended solids, and as such EPA considered it for the 
basis of BPT, multimedia or sand filtration does not reflect the best 
available technology performance for priority and nonconventional 
pollutants.
    For all of the MP&M subcategories (except Railroad Line Maintenance 
and Shipbuilding Dry Dock subcategories), EPA is proposing BAT 
limitations equivalent to BPT. For the Railroad Line Maintenance and 
Shipbuilding Dry Dock subcategories, EPA is not proposing BAT 
limitations. EPA briefly discusses the BAT selection for each of the 
subcategories below and refers to Section IX for a detailed discussion 
of the need for BPT regulation, the selected BPT technology option, the 
calculation of BPT limitations, and the estimated removals and costs of 
BPT for each subcategory.

A. General Metals Subcategory

    EPA has not identified any more stringent economically-achievable 
treatment technology option which it considered to represent BAT level 
of control applicable to General Metals subcategory facilities. 
Therefore, the Agency is proposing to establish BAT equivalent to BPT 
for toxic and nonconventional pollutants for the General Metals 
subcategory. EPA estimates that 20 facilities (less than 1 percent of 
the direct dischargers in this subcategory) will close as a result of 
BAT based on Option 2. EPA found this option to be economically 
achievable for the subcategory as a whole. Additionally, the Agency 
believes that Option 2 represents the ``best available'' technology as 
it achieves a high level of pollutant control, treating all priority 
pollutants to very low levels, often at or near the analytical minimum 
level.
    EPA did evaluate BPT Option 4 as a basis for establishing BAT more 
stringent than the BPT level of control being proposed today. EPA 
estimates that the economic impact due to the additional controls at 
Option 4 levels would result in 35 facility closures (1 percent of the 
direct dischargers in this subcategory). See Section XVI.E for a 
discussion on job losses. While EPA does not have a bright line for 
determining what level of impact is economically achievable for the 
industry as a whole, EPA looked for a breakpoint that would mitigate 
adverse economic impacts without greatly affecting the toxic pound 
equivalents being removed under the proposed rule. By selecting Option 
2 as BAT, EPA was able to reduce facility closures by 43 percent, while 
only losing about 1.5 percent of the toxic pound equivalents that would 
be removed under Option 4. Option 4 resulted in some level of improved 
pollutant reductions; however, the amounts are not very large and the 
cost of implementing the level of control associated with Option 4 is 
disproportionately high. Thus, EPA rejected Option 4 as a basis for BAT 
for this subcategory.

B. Metal Finishing Job Shops Subcategory

    The Agency is proposing to establish BAT equivalent to BPT for 
toxic and nonconventional pollutants for the Metal Finishing Job Shop 
subcategory. EPA estimates that no facilities will close as a result of 
BAT based on Option 2. Therefore, the Agency found this Option to be 
economically achievable. Additionally, the Agency believes that Option 
2 represents the ``best available'' technology as it achieves a high 
level of pollutant control, treating all priority pollutants to very 
low levels, often at or near the analytical minimum level.
    EPA did evaluate transferring technology reflected in BPT Option 4 
as a basis for establishing BAT more stringent than the BPT level of 
control being proposed today. As was the case for BAT based on Option 
2, EPA estimates that no facilities would close as a result of BAT 
based on Option 4. Therefore, EPA does consider Option 4 to be 
economically achievable for this subcategory. However, EPA is not 
proposing to establish BAT limitations based on Option 4 because it 
determined that Option 2 achieves nearly equivalent reductions in 
pound-equivalents for much less cost. By selecting Option 2 as the 
basis for BAT, EPA reduced annualized compliance costs by $1.1 million 
(1996$) while only losing 2 percent of the toxic pound equivalents that 
would be removed under Option 4. The Agency concluded that the 
additional costs of Option 4 do not justify the lack of significant 
additional pollutant removals achieved for direct dischargers in this 
subcategory. Therefore, EPA determined that Option 2 is the ``best 
available'' technology economically achievable for the Metal Finishing 
Job Shop subcategory.

C. Non-Chromium Anodizing Subcategory

    The Agency is proposing to establish BAT equivalent to BPT for 
toxic and nonconventional pollutants for the Non-Chromium Anodizing 
subcategory. As mentioned in the BPT discussion, EPA's survey of the 
MP&M industry did not identify any non-chromium anodizing facilities 
discharging directly to surface waters. All of the non-chromium 
anodizing facilities in EPA's data base are either indirect or zero 
dischargers. EPA consequently could not evaluate any treatment systems 
in place at direct discharging non-chromium anodizing facilities for 
establishing BAT limitations. Therefore, EPA relied on information and 
data from indirect discharging facilities in the Non-Chromium Anodizing 
subcategory. Based on this analysis the Agency believes that Option 2 
represents the ``best available'' technology as it achieves a high 
level of pollutant control, treating all priority pollutants to very 
low levels, often at or near the analytical minimum level.
    EPA did evaluate transferring technology reflected in BPT Option 4 
as a basis for establishing BAT more stringent than the BPT level of 
control being proposed today. However, EPA is not proposing to 
establish BAT limitations based on Option 4 because it determined that 
Option 2 achieves nearly equivalent reductions in pound-equivalents for 
much less cost. EPA used a facility with a flow of 6.25 MGY (the median 
discharge flow for indirect discharging facilities in this subcategory) 
to model the costs and pollutant loads reduced for a direct discharging 
facility. Because direct dischargers are more likely to have treatment 
in place, EPA provided the model facility with treatment in place 
equivalent to Option 1. Based on this model facility, EPA estimated 
that annualized compliance costs per facility for Option 2 will be 
$41,000 (1996$) less than Option 4, and Option 2 will remove only 83 
pound-equivalents less than Option 4. The Agency concluded that the 
additional costs of Option 4 do not justify the additional pollutant 
removals achieved for direct dischargers in this subcategory. 
Therefore, EPA determined that Option 2 is the ``best available'' 
technology economically

[[Page 461]]

achievable for the Non-Chromium Anodizing subcategory.

D. Printed Wiring Board Subcategory

    The Agency is proposing to establish BAT equivalent to BPT for 
toxic and nonconventional pollutants for the Printed Wiring Board 
subcategory. EPA estimates that no facilities will close as a result of 
BAT based on Option 2. Therefore, the Agency found this option to be 
economically achievable. Additionally, the Agency believes that Option 
2 represents the ``best available'' technology as it achieves a high 
level of pollutant control, treating all priority pollutants to very 
low levels, often at or near the analytical minimum level.
    EPA did evaluate BPT Option 4 as a basis for establishing BAT more 
stringent than the BPT level of control being proposed today. As was 
the case for BAT based on Option 2, EPA estimates that no facilities 
would close as a result of BAT based on Option 4. Therefore, EPA does 
consider Option 4 to be economically achievable for this subcategory. 
However, EPA is not proposing to establish BAT limitations based on 
Option 4 because it determined that Option 2 achieves nearly equivalent 
reductions in pound-equivalents for much less cost. By selecting Option 
2 as the basis for BAT, EPA reduced annualized compliance costs by $2 
million (1996$) while only losing 3 percent of the toxic pound 
equivalents that would be removed under Option 4. The Agency concluded 
that the additional costs of Option 4 do not justify the lack of 
significant additional pollutant removals achieved for direct 
dischargers in this subcategory. Therefore, EPA determined that Option 
2 is the ``best available'' technology economically achievable for the 
Printed Wiring Board subcategory.

E. Steel Forming & Finishing Subcategory

    The Agency is proposing to establish BAT equivalent to BPT for 
toxic and nonconventional pollutants for the Steel Forming & Finishing 
subcategory. EPA estimates that no facilities will close as a result of 
BAT based on Option 2. Therefore, the Agency found this Option to be 
economically achievable. Additionally, the Agency believes that Option 
2 represents the ``best available'' technology as it achieves a high 
level of pollutant control, treating all priority pollutants to very 
low levels, often at or near the analytical minimum level.
    EPA did evaluate transferring technology reflected in BPT Option 4 
as a basis for establishing BAT more stringent than the BPT level of 
control being proposed today. EPA is not proposing to establish BAT 
limitations based on Option 4 because it determined that Option 2 
achieves nearly equivalent reductions in pound-equivalents for much 
less cost. By selecting Option 2 as the basis for BAT, EPA reduced 
annualized compliance costs by $2.6 million (1996$) while only losing 3 
percent of the toxic pound equivalents that would be removed under 
Option 4. The Agency concluded that the additional costs of Option 4 do 
not justify the insignificant additional pollutant removals achieved 
for direct dischargers in this subcategory.

F. Oily Wastes Subcategory

    EPA has not identified any more stringent economically-achievable 
treatment technology option which it considered to represent BAT level 
of control applicable to Oily Wastes subcategory facilities. Therefore, 
the Agency is proposing to establish BAT equivalent to BPT for toxic 
and nonconventional pollutants for the Oily Wastes subcategory. EPA 
estimates that no facilities will close as a result of BAT based on 
Option 6. Additionally, the Agency believes that Option 6 represents 
the ``best available'' technology as it achieves a high level of 
pollutant control, treating all priority pollutants to very low levels, 
often at or near the analytical minimum level.
    EPA did evaluate BPT Option 8 (ultrafiltration) as a basis for 
establishing BAT more stringent than the BPT level of control being 
proposed today. As was the case for BAT based on Option 6, EPA 
estimates that no facilities would close as a result of BAT based on 
Option 8. Therefore, EPA does consider Option 8 to be economically 
achievable for this subcategory. However, based on the available data 
base, EPA is not proposing to establish BAT limitations based on Option 
8 because it removes fewer pound-equivalents than Option 6. Therefore, 
the Agency determined that Option 6 is the ``best available'' 
technology economically achievable for the removal of priority 
pollutants from wastewater generated at Oily Wastes subcategory 
facilities.

G. Railroad Line Maintenance Subcategory

    EPA is not proposing to establish BAT regulations for the Railroad 
Line Maintenance subcategory. The Agency concluded that the facilities 
in this subcategory discharge very few pounds of toxic pollutants. EPA 
estimates that 34 railroad line maintenance facilities discharge 1,100 
pound equivalents per year to surface waters, or about 32 pound 
equivalents per year per facility. The Agency based the loadings 
calculations on EPA sampling data, which found very few priority toxic 
pollutants at treatable levels in raw wastewater. Therefore, 
nationally-applicable regulations are unnecessary at this time and 
direct dischargers will remain subject to permit limitations for toxic 
and nonconventional pollutants established on a case-by-case basis 
using best professional judgement.

H. Shipbuilding Dry Dock Subcategory

    EPA is not proposing to establish BAT regulations for the 
Shipbuilding Dry Dock subcategory because of the small number of 
facilities in this subcategory. EPA estimates that there are 6 
shipbuilding facilities operating one or more dry docks in the U.S. 
that discharge directly to surface waters. EPA determined that 
nationally-applicable regulations are unnecessary at this time because 
of the small number of facilities in this subcategory. The Agency 
believes that limitations established on a case-by-case basis using 
best professional judgement can more appropriately address individual 
toxic and nonconventional pollutants that may be present at these six 
facilities.

XII. Pretreatment Standards for Existing Sources (PSES)

A. Need for Pretreatment Standards

    Indirect dischargers in the MP&M industrial category, like the 
direct dischargers, use raw materials that contain many priority 
pollutant and nonconventional metal pollutants. These indirect 
facilities may discharge many of these pollutants to POTWs at 
significant mass or concentration levels, or both. EPA estimates that 
indirect discharging facilities annually discharge approximately 125 
million pounds of priority and nonconventional metals, and 47 million 
pounds of priority and nonconventional organic pollutants.
    Unlike direct dischargers whose wastewater will receive no further 
treatment once it leaves the facility, indirect dischargers send their 
wastewater to POTWs for further treatment, which occurs unless there is 
a bypass, upset, or sewer overflow. EPA establishes pretreatment 
standards for those BAT pollutants that pass through POTWs. Therefore, 
for indirect dischargers, before proposing pretreatment standards, EPA 
examines whether the pollutants discharged by the industry ``pass 
through'' POTWs to waters of the U.S. or interfere with POTW operations 
or sludge disposal practices on a national basis. Generally, to 
determine if pollutants pass through POTWs, EPA compares the percentage

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of the pollutant removed by well-operated POTWs achieving secondary 
treatment with the percentage of the pollutant removed by facilities 
meeting BAT effluent limitations. In this manner, EPA can ensure that 
the combined treatment at indirect discharging facilities and POTWs is 
at least equivalent to that obtained through treatment by direct 
dischargers.
    This approach to the definition of pass-through satisfies two 
competing objectives set by Congress: (1) That standards for indirect 
dischargers be equivalent to standards for direct dischargers, and (2) 
that the treatment capability and performance of POTWs be recognized 
and taken into account in regulating the discharge of pollutants from 
indirect dischargers. Rather than compare the mass or concentration of 
pollutants discharged by POTWs with the mass or concentration of 
pollutants discharged by BAT facilities, EPA compares the percentage of 
the pollutants removed by BAT facilities to the POTW removals. EPA 
takes this approach because a comparison of the mass or concentration 
of pollutants in POTW effluents with pollutants in BAT facility 
effluents would not take into account the mass of pollutants discharged 
to the POTW from other industrial and non-industrial sources, nor the 
dilution of the pollutants in the POTW to lower concentrations from the 
addition of large amounts of other industrial and non-industrial water.
    The primary source of the POTW percent removal data is the ``Fate 
of Priority Pollutants in Publicly Owned Treatment Works'' (EPA 440/1-
82/303, September 1982), commonly referred to as the ``50-POTW Study.'' 
This study presents data on the performance of 50 well-operated POTWs 
that employ secondary biological treatment in removing pollutants. Each 
sample was analyzed for three conventional, 16 non-conventional, and 
126 priority toxic pollutants.
    At the time of the 50-POTW sampling program, which spanned 
approximately 2\1/2\ years (July 1978 to November 1980), EPA collected 
samples at selected POTWs across the U.S. The samples were subsequently 
analyzed by either EPA or EPA-contract laboratories using test 
procedures (analytical methods) specified by the Agency or in use at 
the laboratories. Laboratories typically reported the analytical method 
used along with the test results. However, for those cases in which the 
laboratory specified no analytical method, EPA was able to identify the 
method based on the nature of the results and knowledge of the methods 
available at the time.
    Each laboratory reported results for the pollutants for which it 
tested. If the laboratory found a pollutant to be present, the 
laboratory reported a result. If the laboratory found the pollutant not 
to be present, the laboratory reported either that the pollutant was 
``not detected'' or a value with a ``less than'' sign () indicating 
that the pollutant was below that value. The value reported along with 
the ``less than'' sign was the lowest level to which the laboratory 
believed it could reliably measure. EPA subsequently established these 
lower levels as the minimum levels of quantitation (MLs). In some 
instances, different laboratories reported different (sample-specific) 
MLs for the same pollutant using the same analytical method.
    Because of the variety of reporting protocols among the 50-POTW 
Study laboratories (pages 27 to 30, 50-POTW Study), EPA reviewed the 
percent removal calculations used in the pass-through analysis for 
previous industry studies, including those performed when developing 
effluent guidelines for Organic Chemicals, Plastics, and Synthetic 
Fibers (OCPSF) Manufacturing, Centralized Waste Treatment (CWT), and 
Commercial Hazardous Waste Combustors. EPA found that, for 12 
parameters, different analytical minimum levels were reported for 
different rulemaking studies (10 of the 21 metals, cyanide, and one of 
the 41 organics).
    To provide consistency for data analysis and establishment of 
removal efficiencies, EPA reviewed the 50-POTW Study, standardized the 
reported MLs for use in the final rules for CWT and Transportation 
Equipment Cleaning Industries and for this proposed rule and the Iron 
and Steel proposed rule. A more detailed discussion of the methodology 
used and the results of the ML evaluation are contained in the record 
for today's proposal.
    In using the 50-POTW Study data to estimate percent removals, EPA 
has established data editing criteria for determining pollutant percent 
removals. Some of the editing criteria are based on differences between 
POTW and industry BAT treatment system influent concentrations. For 
many toxic pollutants, POTW influent concentrations were much lower 
than those of BAT treatment systems. For many pollutants, particularly 
organic pollutants, the effluent concentrations from both POTW and BAT 
treatment systems were below the level that could be found or measured. 
As noted in the 50-POTW Study, analytical laboratories reported 
pollutant concentrations below the analytical threshold level, 
qualitatively, as ``not detected'' or ``trace,'' and reported a 
measured value above this level. Subsequent rulemaking studies such as 
the 1987 OCPSF study used the analytical method nominal ``minimum 
level'' (ML) established in 40 CFR part 136 for laboratory data 
reported below the analytical threshold level. Use of the nominal 
minimum level (ML) may overestimate the effluent concentration and 
underestimate the percent removal. Because the data collected for 
evaluating POTW percent removals included both effluent and influent 
levels that were close to the analytical detection levels, EPA devised 
hierarchal data editing criteria to exclude data with low influent 
concentration levels, thereby minimizing the possibility that low POTW 
removals might simply reflect low influent concentrations instead of 
being a true measure of treatment effectiveness.
    EPA has generally used hierarchic data editing criteria for the 
pollutants in the 50-POTW Study. For today's proposal, as in previous 
rulemakings, EPA used the following editing criteria:
     Substitute the standardized pollutant-specific analytical 
minimum level for values reported as ``not detected,'' ``trace,'' 
``less than [followed by a number],'' or a ``number'' less than the 
standardized analytical minimum level,
     Retain pollutant influent and corresponding effluent 
values if the average pollutant influent level is greater than or equal 
to 10 times the pollutant minimum level (10 x ML), and
     If none of the average pollutant influent concentrations 
are at least 10 times the minimum level, then retain average influent 
values greater than or equal to two times the minimum level (2 x ML) 
along with the corresponding average effluent values. (In most cases, 
2 x ML will be equal to or less than 20 g/l.)

EPA then calculates each POTW percent removal for each pollutant based 
on its average influent and its average effluent values. The national 
POTW percent removal used for each pollutant in the pass-through test 
is the median value of all the POTW pollutant specific percent 
removals.
    The rationale for retaining POTW data using the ``10 x ML'' editing 
criterion is based on the BAT organic pollutant treatment performance 
editing criteria initially developed for the 1987 OCPSF regulation (52 
FR 42522, 42545-48; November 5, 1987). BAT treatment system designs in 
the OCPSF industry typically achieved at least 90 percent removal of 
toxic pollutants. Since most

[[Page 463]]

of the OCPSF effluent data from BAT biological treatment systems had 
values of ``not detected,'' the average influent concentration for a 
compound had to be at least 10 times the analytical minimum level for 
the difference to be meaningful (demonstration of at least 90 percent 
removal) and qualify effluent concentrations for calculation of 
effluent limits.
    Additionally, due to the large number of pollutants of concern for 
the MP&M industry, EPA also used data from the National Risk Management 
Research Laboratory (NRMRL) Treatability Database (formerly called the 
Risk Reduction Engineering Laboratory (RREL) database) to augment the 
POTW database for the pollutants which the 50-POTW Study did not cover. 
EPA notes that the 50 POTW Study contains percent removal data for all 
of the pollutants for which EPA is proposing effluent limitations and 
pretreatment standards. The RREL database was used to estimate 
incidental pollutant reductions achieved by the technology for some 
pollutants that are not being expressly limited. This database provides 
information, by pollutant, on removals obtained by various treatment 
technologies. The database provides the user with the specific data 
source and the industry from which the wastewater was generated. For 
each pollutant of concern EPA considered for this proposed rule that 
was not found in the 50-POTW database, EPA used data from the NRMRL 
database, using only treatment technologies representative of typical 
POTW secondary treatment operations (activated sludge, activated sludge 
with filtration, aerated lagoons). EPA further edited these files to 
include information pertaining only to domestic or industrial 
wastewater. EPA used pilot-scale and full-scale data only, and 
eliminated bench-scale data and data from less reliable references. 
These and other aspects of the methodology used for this proposal are 
described in Section 7 of the Technical Development Document.
    The results of the POTW pass-through analysis for indirect 
dischargers are discussed in Sections XII.D to XII.K for each 
subcategory. In addition, Section XIV of today's proposal discusses 
several issues related to the editing criteria applied to the 50-POTW 
data base. EPA solicits comments on its pass-through methodology, 
including the revised editing criteria discussed above as well as the 
additional issues described in Section XIV and in the record for 
today's proposal.

B. Overview of Technology Options for PSES

    Indirect discharging MP&M facilities generate wastewater with 
similar pollutant characteristics to direct discharging facilities. 
Hence, in evaluating technology options for PSES, EPA considered the 
same ten treatment technologies discussed previously for BPT and BAT. 
However, as described below, along with the technology options, EPA 
also evaluated ``low flow'' exclusions for indirect discharging 
facilities (see Sections II.D and VI for additional discussion on the 
low flow exclusions).

C. Overview of Low Flow Exclusions

    For each subcategory, EPA evaluated various low flow exclusions 
(also referred to as ``flow cutoffs'') for indirect dischargers. The 
Agency considered several factors in determining what flow level, if 
any, is appropriate for excluding facilities from compliance with 
pretreatment standards. For several of the subcategories, EPA 
considered the local control authorities' increased burden associated 
with the development of new permits or other control mechanisms for 
MP&M facilities. For some subcategories, the Agency considered flow 
exclusions as a way to reduce economic impacts. EPA also considered the 
amount of pollutant (in pound-equivalents) discharged per year by the 
subcategory and by each of the facilities on an average annual basis, 
in conjunction with the costs of regulation, to identify an appropriate 
level for an exclusion. In cases where EPA is proposing an option that 
also specifies a flow cutoff, it means that facilities with annual 
wastewater flow below the cutoff would not be subject to the MP&M 
categorical pretreatment standards. These facilities would remain 
subject to the general pretreatment regulation at 40 CFR part 403 or 
their existing categorical pretreatment standards (e.g., 40 CFR part 
413 or part 433). For the Metal Finishing Job Shops subcategory, 
although the proposed option does not contain a flow cutoff, several 
other options with various flow cutoffs are discussed in today's 
proposal. Some of these options would require excluded facilities to 
remain covered by categorical pretreatment standards under 40 CFR part 
413 (Electroplating) and 40 CFR part 433 (Metal Finishing). In 
addition, some indirect discharging facilities in the General Metals 
subcategory that discharge less than 1 MGY will remain covered by the 
pretreatment standards in 40 CFR part 433. EPA is not proposing 
pretreatment standards for the Non-Chromium Anodizing subcategory. 
Therefore, all indirect discharging facilities in this subcategory will 
remain subject to the applicable pretreatment standards in 40 CFR part 
413 or 40 CFR part 433.
    In this section, the Agency discusses only some of the flow cutoff 
options for each subcategory. EPA presents its analysis of a full range 
of flow cutoff options for indirect dischargers in each subcategory in 
the Technical Development Document.
    Table XII.C-1 below summarizes the pounds of pollutants removed by 
the proposed options for indirect dischargers in each subcategory, and 
Table XII.C-2 summarizes the costs and economic impacts associated with 
the proposed options for indirect dischargers in each subcategory with 
proposed standards. EPA is not proposing pretreatment standards for the 
Non-Chromium Anodizing, Railroad Line Maintenance, and Shipbuilding Dry 
Dock subcategories for the reasons described later in this section. 
(See Section IX for summary tables for direct dischargers).

   Table XII.C-1.--Annual Pounds of Pollutant Removed by the Proposed PSES Option for Indirect Dischargers by
                                                   Subcategory
----------------------------------------------------------------------------------------------------------------
                                                            Priority and         Priority and
      Subcategory (number of         Selected option      nonconventional      nonconventional     Cyanide (lb-
           facilities)                (flow cutoff)     metals (lb-removed/     organics (lb-       removed/yr)
                                                                yr)              removed/yr)
----------------------------------------------------------------------------------------------------------------
General Metals (3,055)...........  Option 2 (1 MGY)...  28.1 million.......  7.7 million........        284,000.
Metal Finishing Job Shops (1,514)  Option 2...........  2.4 million........  47,000.............      1 million.
Printed Wiring Boards (621)......  Option 2...........  2.6 million........  14,000.............        230,000.
Steel Forming and Finishing (110)  Option 2...........  617,000............  16,000.............            181.

[[Page 464]]


Oily Waste (226).................  Option 6 (2 MGY)...  191,000............  1.1 million........              0.
----------------------------------------------------------------------------------------------------------------


    Table XII.C-2.--Annual Costs and Economic Impacts of the Proposed PSES Option for Indirect Dischargers by
                                                   Subcategory
----------------------------------------------------------------------------------------------------------------
                                                                                                     Economic
                                                                                                      impacts
                                                                                                     (facility
                                                                         Annualized compliance     closures) of
   Subcategory (number of facilities)        Selected option (flow     costs for selected option     selected
                                                    cutoff)                     ($1996)               option
                                                                                                    (percent of
                                                                                                     regulated
                                                                                                  subcategory *)
----------------------------------------------------------------------------------------------------------------
General Metals (3,055)..................  Option 2 (1 MGY)..........  1.57 billion..............         24 (1%)
Metal Finishing Job Shops (1,514).......  Option 2..................  178 million...............       128 (10%)
Printed Wiring Boards (621).............  Option 2..................  147 million...............          7 (1%)
Steel Forming and Finishing (110).......  Option 2..................  24 million................          6 (6%)
Oily Waste (226)........................  Option 6 (2 MGY)..........  10 million................         14 (1%) 
----------------------------------------------------------------------------------------------------------------
* Baseline closures will not be regulated and, therefore, are not included when estimating the percentage of
  regulatory closures (% regulatory closures = regulatory closures/all facilities in subcategory excluding
  baseline closures).

D. General Metals Subcategory

1. Need for PSES
    As discussed in Section XII.A, one of the factors that EPA uses to 
determine the need for pretreatment standards is whether the pollutants 
discharged by an industry pass through a POTW. The Agency only applied 
the pass-through analysis to pollutants that it selected for regulation 
under BAT. For the General Metals subcategory, EPA determined that 13 
pollutants pass through; and therefore, EPA is proposing pretreatment 
standards equivalent to BAT for these pollutants.
2. Selected PSES Options
    As discussed in Section XII.B, in the Agency's engineering 
assessment of the best available technology for pretreatment of 
wastewater from the General Metals Subcategory, EPA considered the same 
technology options for PSES as it did for BAT with the additional 
consideration of a flow cutoff. The Agency is proposing BAT Option 2 
with a 1 MGY flow cutoff for PSES. EPA is proposing Option 2 for many 
of the same reasons it selected that option for BPT and BAT (See 
Sections IX.A and XI.A) and provides additional rationale below.
    EPA determined that Option 2 represented the best available 
technology and that Option 2 with a 1 MGY flow cutoff was economically 
achievable and greatly reduced the burden on POTWs. This option results 
in 24 facility closures (less than 1 percent of the indirect 
discharging General Metals subcategory population). See Section XVI.E 
for a discussion on job losses. Additionally, the Agency believes that 
Option 2 represents the ``best available'' technology as it achieves a 
high level of pollutant control, treating all priority pollutants to 
very low levels, often at or near the analytical minimum level. 
Approximately 15 percent of the indirect discharging facilities in the 
General Metals subcategory employ chemical precipitation followed by a 
sedimentation (Option 2) while 1 percent employ microfiltration after 
chemical precipitation (Option 4).
    EPA did evaluate Option 4 with a 1 MGY flow cutoff as a basis for 
establishing PSES. EPA estimates that the economic impact due to the 
additional controls at Option 4 levels would result in 92 facility 
closures (less than 1 percent of the indirect dischargers in this 
subcategory). See Section XVI.E for a discussion on job losses. While 
EPA does not have a bright line for determining what level of impact is 
economically achievable for the industry as a whole, EPA looked for a 
breakpoint that would mitigate adverse economic impacts without greatly 
affecting the toxic pound equivalents being removed under the proposed 
rule. By selecting Option 2 as PSES, EPA was able to reduce facility 
closures by more than two-thirds, while only losing a little over one 
percent of the toxic pound equivalents from control under Option 4. The 
Agency concluded that the additional facility closures associated with 
Option 4 do not justify the insignificant additional pollutant removals 
achieved for indirect dischargers in this subcategory.
    Considering the large number of indirect dischargers in the General 
Metals subcategory which have the potential to be covered by this 
proposed regulation, an important issue to the affected industry and to 
permit writers is the potentially enormous administrative burden 
associated with issuing permits or other control mechanisms for all of 
these facilities. Therefore, in developing this proposal, EPA has 
looked for means of reducing the administrative burden, reducing 
monitoring requirements, and reducing reporting requirements. In order 
to meet this end, the Agency is proposing a 1 million gallon per year 
(MGY) flow cutoff for the General Metals subcategory. Under this 
proposed option, facilities in the General Metals subcategory that 
discharge greater than 1 MGY of MP&M process wastewater would be 
subject to the proposed categorical pretreatment standards. Facilities 
in the General Metals subcategory that discharge 1 MGY or less would 
not be subject to MP&M PSES requirements. However, some of the 
facilities in this subcategory discharging under 1 MGY are currently 
covered by 40 CFR part 433, Metal Finishing PSES or PSNS, and these 
indirect dischargers would remain subject to those pretreatment 
standards and the general pretreatment standards at 40 CFR part 403.
    The Agency determined that the 1 MGY flow cutoff was appropriate 
for the

[[Page 465]]

General Metals subcategory based on several factors. First, and the 
most important factor, was the overall size of the General Metals 
subcategory. EPA estimates that there are over 26,000 indirect 
discharging facilities in the General Metals subcategory, of which 74 
percent are not currently regulated by nationally established effluent 
guidelines. Establishing an MP&M pretreatment standard for all 26,000 
facilities would greatly increase the number of permits or other 
control mechanisms for which local authorities are responsible. (EPA 
estimates that there are approximately 30,000 control mechanisms 
today.) EPA concluded that this increased permit burden was not 
reasonable and therefore explored potential flow cutoffs as a way to 
reduce the impact on POTW permitting authorities.
    Second, EPA is proposing the 1 MGY flow cutoff for this subcategory 
based in part on the small number of pound-equivalents that would be 
removed by facilities with annual wastewater flows less than or equal 
to 1 MGY. EPA determined that 89 percent of the indirect discharging 
facilities in the General Metals subcategory discharge less than or 
equal to 1 MGY, yet these facilities are responsible for less than 6 
percent of the total pound-equivalents currently discharged. If the 
Agency proposed pretreatment standards for facilities in the General 
Metals subcategory that discharged less than or equal to 1 MGY, it 
estimates average removals of only 22 pound-equivalents per facility 
per year for those facilities. EPA recently decided not to promulgate 
pretreatment standards for two industrial categories, Industrial 
Laundries (64 FR 45072) and Landfills (65 FR 3008), based on low 
removals of toxic pound equivalents by facilities in those categories. 
In the industrial laundries rule, EPA decided not to promulgate 
pretreatment standards based on 32 toxic pound equivalents per facility 
per year, and in the landfills effluent guidelines, EPA decided not to 
promulgate pretreatment standards for non-hazardous landfills based on 
the removal of only 14 toxic pound equivalents per facility per year. 
In both instances, the Agency considered that the small additional 
removals that would be achieved through regulation did not warrant 
adoption of national categorical standards.
    The Agency concluded that regulation of facilities discharging only 
22 pound-equivalents per year was not justified by the additional 
permitting burden associated with these facilities. Although this 
decision is based upon a subset of small facilities, and not an entire 
subcategory as was done before, EPA believes this approach would allow 
Control Authorities to focus their efforts on the facilities 
discharging the vast majority of the pollutants, rather than 
dissipating their limited resources on sites contributing much less to 
the overall problem. EPA acknowledges that this may create an economic 
advantage for the smaller facilities, and solicits comment on this 
exclusion.
    EPA also closely evaluated Option 2 with a 2 MGY flow cutoff for 
the General Metals subcategory. The Agency is not proposing this option 
because it does not reduce the number of facility closures (24) or 
further reduce the burden on control authorities in a significant way, 
and there is a significant number of pound equivalents associated with 
facilities discharging between 1 and 2 MGY. EPA determined that only 3 
percent more of the facilities in this subcategory discharge between 1 
and 2 MGY. This small number of facilities accounts for an additional 
13 percent of the annual pollutant discharge load (in pound-
equivalents). If EPA proposed Option 2 with a 2 MGY flow cutoff, the 
economic impacts would not be reduced. Based on these considerations, 
EPA is not proposing the 2 MGY flow cutoff for the General Metals 
subcategory. EPA concluded that the 1 MGY flow cutoff was the most 
appropriate option in terms of balancing POTW burden reduction with 
pollutant removals and mitigating economic impacts. Table XII.C-1 above 
shows the pounds of pollutants removed by the proposed option, and 
Table XII.C-2 summarizes the costs and economic impacts associated with 
the proposed option. Where these General Metals facilities discharge 
less than or equal to 1 MGY to a POTW, these pretreatment standards 
proposed today do not apply; however, facilities are still subject to 
other applicable pretreatment standards, including those established 
under parts 413 and 433. EPA requests comment on the 1 MGY flow cutoff 
and whether a higher or lower cutoff would be appropriate. EPA also 
requests comment on whether the flow cutoff should be different for 
facilities currently covered under 40 CFR part 413 or part 433 and 
whether or not that would create an unfair economic advantage for those 
facilities (e.g., captive electroplating shops in General Metals 
remaining regulated under 40 CFR part 433 but Metal Finishing Job Shops 
being regulated under the proposed MP&M rule).
3. Calculation of PSES
    Based on the results of the pass-through analysis discussed in 
Section XII.D.1, EPA is proposing pretreatment standards for existing 
sources in the General Metals subcategory equivalent to those 
limitations proposed for BAT for the pollutants listed at Sec. 438.15 
(as provided in the codified regulation that accompanies this 
preamble). EPA determined that all of the pollutants listed in 
Sec. 438.15 (except for Total Sulfide, TOC, and TOP) pass through 
POTWs. EPA is proposing a limitation for total sulfide based on 
potential POTW interference or upset associated with discharges of 
total sulfide from MP&M facilities. EPA is proposing limitations for 
TOC and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXI.C. for a discussion of monitoring 
flexibility.) (See Section XXII.C. for a discussion of monitoring 
flexibility.)
4. Compliance Date
    EPA is proposing to establish a three-year deadline for compliance 
with PSES. Design and construction of systems adequate for compliance 
with PSES will be a substantial undertaking for many MP&M sites.

E. Metal Finishing Job Shops Subcategory

1. Need for PSES
    As discussed above in Section XII.A., one of the factors that EPA 
uses to determine the need for pretreatment standards is whether the 
pollutants discharged by an industry pass through a POTW. The Agency 
only applies the pass-through analysis to pollutants that it selected 
for regulation under BAT. For the Metal Finishing Job Shops 
subcategory, EPA determined that 12 pollutants pass through; and 
therefore, EPA is proposing pretreatment standards equivalent to BAT 
for these pollutants.
2. Selected PSES Option
    As discussed in Section XII.B, in the Agency's engineering 
assessment of the best available technology for pretreatment of 
wastewater from the Metal Finishing Job Shops Subcategory, EPA 
considered the same technology options for PSES as it did for BAT with 
the additional consideration of a flow cutoff. The Agency is proposing 
BAT Option 2 for PSES for many of the same reasons it selected that 
option for BPT and BAT (See Section IX.B and XI.B) and provides 
additional rationale below. EPA is proposing that pretreatment 
standards based on Option 2 be applied to all facilities (i.e., no flow 
exclusion) for the Metal Finishing Job Shops subcategory.

[[Page 466]]

    The Agency estimates that 1,514 metal finishing job shop facilities 
currently discharge MP&M process wastewater to POTWs. The Agency 
projects that 128 of these facilities (10 percent of the indirect 
discharging facilities when baseline closures are taken into 
consideration) might close as a result of the proposed option (see 
Section XVI.E for a discussion on job losses). EPA concluded that this 
level of impact was economically achievable for the subcategory as a 
whole, but in an effort to minimize the impacts, considered several 
flow exclusions and compliance alternatives.
    The Agency believes that Option 2 represents the ``best available'' 
technology as it achieves a high level of pollutant control, treating 
all priority pollutants to very low levels, often at or near the 
analytical minimum level. Approximately 55 percent of the indirect 
discharging facilities in the Metal Finishing Job Shops subcategory 
employ chemical precipitation followed by sedimentation (Option 2) 
while less than 1 percent employ microfiltration after chemical 
precipitation (Option 4).
    EPA did evaluate Option 4 as a basis for establishing PSES. EPA 
estimates that the economic impact due to the additional controls at 
Option 4 levels would result in 393 facility closures (32 percent of 
the indirect discharging facilities in this subcategory). (See Section 
XVI.E for a discussion on job losses). Thus, EPA rejected Option 4 as 
not economically achievable.
    The Agency evaluated Option 2 with several levels of flow cutoffs, 
compliance options, and various combinations of the two. EPA analyzed 
the cutoffs and alternative compliance options in terms of reduction in 
economic impacts and quantity of toxic pound-equivalents discharged to 
the environment. EPA did not consider the reduction in POTW burden for 
this subcategory, unlike the General Metals subcategory, because EPA 
has already established PSES for all of the facilities in this 
subcategory under 40 CFR part 413 and 40 CFR part 433, and local 
control authorities would not have to develop entirely new permits (or 
other control mechanisms) for these facilities.
    With respect to alternatives, first, EPA analyzed a 1 MGY flow 
cutoff, which would exclude 831 of the 1,514 estimated metal finishing 
job shop facilities (or 457 of the 1,231 facilities after baseline 
closures are removed from the analysis), and would reduce the economic 
impacts for 23 of the 128 facilities EPA projected would close under 
Option 2. This represents less than 2 percent of the 1,231 metal 
finishing jobs that operate in the baseline and 18 percent of the 
projected facility closures under Option 2. This means that there are 
still 105 of the 128 facilities that EPA predicts to close with a 1 MGY 
flow cutoff. Further, EPA determined that the proposed regulation would 
control an average of 135 pound-equivalents per year from facilities 
discharging less than 1 MGY. This is higher than the level at which EPA 
has previously determined that discharges are not significant enough to 
warrant national regulation. Facilities discharging less than 1 MGY are 
associated with removals under the proposed option of about 61,000 
pound-equivalents (or about 3 percent of the removals associated with 
the proposed option) at an incremental cost-effectiveness of about $300 
per pound-equivalent ($1981). This is higher than has generally been 
associated with pretreatment standards in the past, though not 
necessarily higher than has been associated with the smaller facilities 
regulated with pretreatment standards in the past. This is to be 
expected since smaller facilities incur the same level of costs for 
monitoring as larger facilities and are sometimes forced to purchase 
larger capacity treatment units than they would need due to 
availability. Nonetheless, the Agency concluded that the pollutant 
reductions associated with Option 2 were feasible and achievable and 
the economic impacts were not substantially mitigated under the 1 MGY 
flow cutoff, so a 1 MGY flow cutoff is not being proposed for the Metal 
Finishing Job Shops subcategory. EPA requests comment on the use of a 
flow cutoff for this subcategory.
    Second, EPA considered an option with (a) MP&M pretreatment 
standards for facilities discharging greater than 1 MGY and (b) a 
pollution prevention alternative for those discharging less than 1 MGY. 
Under this option, EPA would exclude from the MP&M numeric pretreatment 
standards based on Option 2 those metal finishing job shops discharging 
less than 1 MGY that choose to perform the pollution prevention and 
water conservation activities discussed in Section XXI.D (referred to 
as the ``P2 alternative''). EPA would require the low flow facilities 
to continue to meet the pretreatment standards codified at 40 CFR part 
433, which remain unchanged by today's proposal. All facilities 
discharging greater than 1 MGY (and those facilities discharging less 
than 1 MGY but not choosing the P2 alternative) would be subject to the 
MP&M pretreatment standards for this subcategory. In analyzing this 
option, EPA assumed that all facilities discharging less than 1 MGY 
chose the P2 alternative. EPA's analysis shows that this option would 
reduce the facility closures for 23 of the 128 facilities EPA projected 
would close under Option 2 (no flow cutoff). As with the 1 MGY flow 
cutoff approach discussed above, this represents less than 2 percent of 
the 1,231 metal finishing jobs that operate in the baseline and about 
18% of the closures projected by the proposed option. Further, although 
the P2 alternative would be somewhat effective in reducing toxic 
discharges, the option is not as protective as the numeric pretreatment 
standards based on Option 2. For facilities discharging less than 1 
MGY, EPA estimates that the P2 alternative would control 59 pound-
equivalents per facility per year (compared to 135 pound-equivalents 
per facility at Option 2). Thus, EPA is not proposing the option of a 1 
MGY flow cutoff combined with a P2 alternative for today's proposal. 
EPA solicits comment and data on the pollutant reductions that can be 
achieved using the practices outlined in Section XXI.D.
    Third, EPA analyzed a 2 MGY flow cutoff, which would exclude 1,024 
facilities (66 percent) from MP&M pretreatment standards. Excluding a 
larger number of facilities (compared to the 1 MGY cutoff option) 
resulted in a smaller number of facility closures. For this option, EPA 
predicts that 59 facilities (approximately 5 percent of the indirect 
discharging facilities) might close. EPA estimates that the facilities 
discharging less than 2 MGY represent less than 12 percent of the total 
pound-equivalents currently discharged by facilities in this 
subcategory. For facilities discharging less than 2 MGY, EPA estimates 
that pretreatment standards would remove an average of 189 pound-
equivalents per facility per year. While a 2 MGY flow cutoff reduced 
the number of facility closures, EPA concluded that the pollutant 
reductions associated with Option 2 were feasible and achievable and is 
not proposing a 2 MGY flow cutoff. EPA requests comment on the 2 MGY 
flow cutoff for this subcategory.
    Fourth, EPA analyzed the 2 MGY flow cutoff with the pollution 
prevention alternative for those facilities below the cutoff. Under 
this option, EPA would exclude from the MP&M numeric pretreatment 
standards based on Option 2 those metal finishing job shops discharging 
less than 2 MGY that choose to perform the pollution prevention and 
water conservation activities discussed in Section XXI.D (i.e. the P2 
alternative). EPA would require the low flow facilities to continue to 
meet the

[[Page 467]]

pretreatment standards codified at 40 CFR part 433, which remain 
unchanged by today's proposal. All facilities discharging greater than 
2 MGY (and those facilities discharging less than 2 MGY but not 
choosing the P2 alternative) would be subject to the MP&M pretreatment 
standards for this subcategory. In analyzing this option, EPA assumed 
that all facilities discharging less than 2 MGY chose the P2 
alternative. EPA's analysis shows that this option may not reduce the 
number of facility closures any further than a 1 MGY flow cutoff (or 1 
MGY P2 Alternative). The model facilities representing the facilities 
that close with flows of 2 MGY or less would require annualized costs 
to be reduced at least 68 percent in order to avoid closure. Since 
there are some compliance costs associated with implementing the 
practices of the P2 alternative, EPA estimates that these may close 
under the P2 Alternative. See Section XVI.E for a discussion on job 
losses. Although the P2 alternative reduces the number of facility 
closures as compared to an option with no flow cutoff, the option is 
not as protective as numeric pretreatment standards based on Option 2. 
For facilities discharging less than 2 MGY, EPA estimates that the P2 
alternative would control an average of 67 pound-equivalents per 
facility per year (compared to 189 pound-equivalents per facility at 
Option 2). Thus, EPA is not proposing the option of 2 MGY flow cutoff 
combined with a P2 alternative. EPA solicits comment and data on the 
pollutant reductions that can be achieved using the practices outlined 
in Section XXI.D.
    In summary, for all of the flow cutoff and P2 alternatives that EPA 
considered for this subcategory, the Agency identified no combination 
that would significantly reduce the economic impacts without also 
significantly reducing control of pollutants. At all the flow cutoffs 
and compliance alternatives, EPA concluded that the potential removals 
the Agency would be choosing to forego were above levels which EPA has 
previously determined insufficient to warrant national categorical 
pretreatment standards. Thus, EPA is not proposing a flow cutoff for 
this subcategory. Under the proposed option, all facilities in this 
subcategory would be subject to the pretreatment standards, which would 
reduce pass through of pollutants based on a technology EPA has 
determined to be technologically feasible and economically achievable. 
The Agency is soliciting comment on alternatives that might reduce the 
economic impact and still provide acceptable environmental protection, 
including all of the options discussed above. See Section XXI.D for a 
discussion of the P2 alternative and Section XXIII for solicitation of 
comments on this issue. Table XII.C-1 above shows the pounds of 
pollutants removed by the proposed option, and Table XII.C-2 summarizes 
the costs and economic impacts associated with the proposed option.
3. Calculation of PSES
    Based on the results of the pass-through analysis discussed in 
Section XII.E.1., EPA is proposing pretreatment standards for existing 
sources in the Metal Finishing Job Shops subcategory equivalent to 
those limitations proposed for BAT for the pollutants listed at 
Sec. 438.25 (as provided in the codified regulation that accompanies 
this preamble). EPA determined that all of the pollutants listed in 
Sec. 438.25 (except for Total Sulfide, TOC, and TOP) pass through 
POTWs. EPA is proposing a limitation for total sulfide based on 
potential POTW interference or upset associated with discharges of 
total sulfide from MP&M facilities. EPA is proposing limitations for 
TOC and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXII.C. for a discussion of monitoring 
flexibility.)
4. Compliance Date
    EPA is proposing to establish a three-year deadline for compliance 
with PSES. Design and construction of systems adequate for compliance 
with PSES will be a substantial undertaking for many MP&M sites.

F. Non-Chromium Anodizing Subcategory

1. Rationale for Not Proposing PSES
    EPA is proposing to not establish PSES for the Non-Chromium 
Anodizing subcategory based on the economic impacts associated with 
Option 2 and the small quantity of toxic pollutants discharged by 
facilities in this subcategory remaining covered at an economically-
achievable flow cutoff. EPA determined that 60 percent of the indirect 
discharging facilities in this subcategory would close as a result of 
complying with Option 2 based standards. Pretreatment standards for 
this subcategory based on either Option 2 or Option 4 would require 
facilities to remove large quantities of aluminum, a metal that is 
beneficial to POTWs because it assists in the flocculation of 
wastewater prior to sedimentation. Aluminum anodizers use a large 
quantity of water in their anodizing processes and produce a wastewater 
that contains mostly aluminum. If the Agency proposed pretreatment 
standards for this subcategory, even without regulating aluminum, the 
standards would require facilities to install very large treatment 
systems (because of their high flow volume) and would result in the 
removal of large quantities of aluminum in order to remove small 
quantities of other metals such as nickel, zinc, and manganese. 
Therefore, EPA determined that the benefits of the aluminum discharge 
to POTWs outweighed the benefits gained from the removal of small 
quantities of other metals. In addition, because EPA has already 
promulgated pretreatment standards for non-chromium anodizers at 40 CFR 
parts 413 and 433, there is already a level of control for the small 
quantities of other metals being discharged along with the aluminum. 
Facilities subject to this subcategory must still comply with 
applicable PSES limitations (either 40 CFR part 413 or 40 CFR part 
433). 40 CFR 438.40(b).

G. Printed Wiring Board Subcategory

1. Need for PSES
    As discussed above in Section XII.A, one of the factors that EPA 
uses to determine the need for pretreatment standards is whether the 
pollutants discharged by an industry pass through a POTW. The Agency 
only applies the pass-through analysis to pollutants that it selected 
for regulation under BAT. For the Printed Wiring Board subcategory, EPA 
determined that 9 pollutants pass through; and therefore, EPA is 
proposing pretreatment standards equivalent to BAT for these 
pollutants.
2. Selected PSES Option
    As discussed in Section XII.B above, in the Agency's engineering 
assessment of the best available technology for pretreatment of 
wastewater from the Printed Wiring Board Subcategory, EPA considered 
the same technology options for PSES as it did for BAT with the 
additional consideration of a flow cutoff exclusion. The Agency is 
proposing Option 2 for PSES for many of the same reasons it selected 
that option for BPT and BAT (See Section IX.D and XI.D) and provides 
additional rationale below. EPA also determined that pretreatment 
standards based on Option 2 for all facilities (i.e., no flow 
exclusion) are appropriate for the Printed Wiring Board subcategory. 
The Agency estimates that 621 printed wiring board facilities currently 
discharge MP&M process wastewater to POTWs. The Agency projects that 7 
of these facilities (1 percent of the current indirect

[[Page 468]]

discharging population) might close as a result of the MP&M regulation 
(see Section XVI.E for a discussion on job losses). EPA concluded that 
this level of impact was economically achievable for the subcategory as 
a whole, but in an effort to minimize the impacts (and or maintain 
existing limitations for facilities where potential removals may not be 
sufficient to warrant national regulation), considered flow exemptions 
and compliance alternatives.
    The Agency believes that Option 2 represents the ``best available'' 
technology as it achieves a high level of pollutant control, treating 
all priority pollutants to very low levels, often at or near the 
analytical minimum level. Approximately 80 percent of the indirect 
discharging facilities in the Printed Wiring Board subcategory employ 
chemical precipitation followed by sedimentation (Option 2) while 2 
percent employ microfiltration after chemical precipitation (Option 4).
    EPA did evaluate Option 4 as a basis for establishing PSES. EPA 
estimates that the economic impact due to the additional controls at 
Option 4 levels would result in 18 more facility closures than Option 2 
(total of 25 closures). EPA itEPA is not proposing to establish PSES 
limitations based on Option 4 because it determined that Option 2 
achieves nearly equivalent reductions in pound-equivalents for much 
less cost. By selecting Option 2 as the basis for PSES, EPA reduced 
annualized compliance costs by $75 million (1996$) while only losing 
0.5 percent of the toxic pound equivalents that would be removed under 
Option 4. The Agency concluded that the additional costs of Option 4 do 
not justify the additional insignificant amount of pollutant removals 
achieved for indirect dischargers in this subcategory. Therefore, EPA 
determined that Option 2 is the ``best available'' technology 
economically achievable for the Printed Wiring Board subcategory.
    Although EPA concluded that the level of economic impact associated 
with Option 2 with no flow cutoff was economically achievable, it 
considered flow exclusions in an effort to minimize the impacts and/or 
maintain existing limitations for facilities where potential removals 
may not be significant enough to warrant national regulations. EPA did 
not consider the reduction in POTW burden for this subcategory, unlike 
the General Metals subcategory, because EPA has already established 
PSES for all of the facilities in this subcategory under 40 CFR parts 
413 and 433, and local control authorities would not have to develop 
entirely new permits (or other control mechanisms) for these 
facilities. EPA analyzed a 1 MGY flow cutoff, which would exclude 85 
facilities, but would not reduce economic impacts. The same 7 
facilities that EPA predicted to close with no flow cutoff are also 
expected to close with a 1 MGY flow cutoff. EPA determined that the 
proposed regulation would remove a total of less than 500 pound 
equivalents from the facilities discharging less than 1 MGY (after 
removing baseline closures from the analysis), or less than 10 pound-
equivalents per facility. The incremental removals beyond current 
regulations is very small for facilities less than 1 MGY, and therefore 
EPA will consider the 1 MGY cutoff at final. However, the Agency 
concluded that the pollutant reductions associated with Option 2 were 
feasible and achievable, the economic impacts were not mitigated at a 1 
MGY flow cutoff for this subcategory, and POTW burden would not be 
reduced with a flow cutoff, and is thus not proposing a 1 MGY flow 
cutoff for this subcategory. The Agency solicits comments on a 1 MGY 
flow cutoff, with the existing regulation applying to facilities under 
1 MGY. EPA also solicits comment on the implementation and market 
consequences of this option. Table XII.C-1 above shows the pounds of 
pollutants removed by the proposed option, and Table XII.C-2 summarizes 
the costs and economic impacts associated with the proposed option.
3. Calculation of PSES
    Based on the results of the pass-through analysis discussed in 
Section XII.G.1., EPA is proposing pretreatment standards for existing 
sources in the Printed Wiring Board subcategory equivalent to those 
limitations proposed for BAT for the pollutants listed at Sec. 438.45 
(as provided in the codified regulation that accompanies this 
preamble). EPA determined that all of the pollutants listed in 
Sec. 438.45 (except for Total Sulfide, TOC, and TOP) pass through 
POTWs. EPA is proposing a limitation for total sulfide based on 
potential POTW interference or upset associated with discharges of 
total sulfide from MP&M facilities. EPA is proposing limitations for 
TOC and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXI.C for a discussion of monitoring 
flexibility.)
4. Compliance Date
    EPA is proposing to establish a three-year deadline for compliance 
with PSES. Design and construction of systems adequate for compliance 
with PSES will be a substantial undertaking for many MP&M sites.

H. Steel Forming and Finishing Subcategory

1. Need for PSES
    As discussed above in Section XII.A, one of the factors that EPA 
uses to determine the need for pretreatment standards is whether the 
pollutants discharged by an industry pass through a POTW. The Agency 
only applies the pass-through analysis to pollutants that it selected 
for regulation under BAT. For the Steel Forming and Finishing 
subcategory, EPA determined that 13 pollutants pass through; and 
therefore, EPA is proposing pretreatment standards equivalent to BAT 
for these pollutants.
2. Selected PSES Option
    As discussed in Section XII.B above, in the Agency's engineering 
assessment of the best available technology for pretreatment of 
wastewater from the Steel Forming and Finishing Subcategory, EPA 
considered the same technology options for PSES as it did for BAT with 
the additional consideration of a flow cutoff exclusion. The Agency is 
proposing Option 2 for PSES for many of the same reasons it selected 
that option for BPT and BAT (See Section IX.E and XI.E) and provides 
additional rationale below. EPA is proposing pretreatment standards 
based on Option 2 for all facilities (i.e., no flow exclusion) for the 
Steel Forming and Finishing subcategory.
    The Agency estimates that 110 steel forming and finishing 
facilities currently discharge MP&M process wastewater to POTWs. The 
Agency projects that 6 of these facilities (6 percent of the current 
indirect discharging population) might close as a result of the MP&M 
regulation (see Section XVI.E for a discussion on job losses). EPA 
concluded that this level of impact was economically achievable for the 
subcategory as a whole, but in an effort to minimize the impacts, 
considered flow exemptions and compliance alternatives.
    The Agency believes that Option 2 represents the ``best available'' 
technology as it achieves a high level of pollutant control, treating 
all priority pollutants to very low levels, often at or near the 
analytical minimum level. Approximately 63 percent of the indirect 
discharging facilities in the Steel Forming and Finishing subcategory 
employ chemical precipitation followed by sedimentation (Option 2) 
while no facilities employ microfiltration after chemical precipitation 
(Option 4).
    EPA did evaluate Option 4 as a basis for establishing PSES. EPA 
estimates

[[Page 469]]

that the economic impact due to the additional controls at Option 4 
levels would result in the same number of facility closures (6) as 
Option 2. Therefore, EPA does consider Option 4 to be economically 
achievable for this subcategory. However, EPA is not proposing to 
establish PSES limitations based on Option 4 because it determined that 
Option 2 achieves nearly equivalent reductions in pound-equivalents for 
much less cost. By selecting Option 2 as the basis for PSES, EPA 
reduced annualized compliance costs by $12 million (1996$) while only 
losing 0.6 percent of the toxic pound equivalents that would be removed 
under Option 4. The Agency concluded that the additional costs of 
Option 4 do not justify the additional insignificant pollutant removals 
achieved for indirect discharging facilities in this subcategory. 
Therefore, EPA determined that Option 2 is the ``best available'' 
technology economically achievable for the Steel Forming and Finishing 
subcategory.
    Although EPA concluded that the level of economic impact associated 
with Option 2 with no flow cutoff was economically achievable, it 
considered flow exclusions in an effort to minimize the impacts. EPA 
did not consider the reduction in POTW burden for this subcategory, 
unlike the General Metals subcategory, because EPA has already 
established PSES for all of the facilities in this subcategory under 40 
CFR 420, and local control authorities would not have to develop 
entirely new permits (or other control mechanisms) for these 
facilities. However, to mitigate economic impacts (and or maintain 
existing limitations for facilities where potential removals may not be 
sufficient to warrant national regulation), EPA analyzed a 1 MGY flow 
cutoff, which would exclude 21 facilities (after accounting for 
baseline closures), and a 2 MGY flow cutoff which would exclude 30 
facilities. Neither a 1 MGY flow cutoff nor a 2 MGY flow cutoff would 
reduce economic impacts. The same 6 facilities that EPA predicted to 
close with no flow cutoff are also expected to close with either a 1 or 
2 MGY flow cutoff. However, a 1 MGY flow cutoff would eliminate less 
than 100 total pound-equivalents that would be removed under the 
proposed option, or less than 5 pound-equivalents per excluded 
facility, while a 2 MGY flow cutoff would eliminate less than 200 
pound-equivalents total, or less than 7 pound-equivalents per excluded 
facility. These incremental removals beyond current regulations are 
very small, and therefore EPA will consider the 1 and 2 MGY cutoffs as 
final. Although a 3 MGY flow cutoff would reduce projected economic 
impacts by half (3 projected closures instead of 6), it would eliminate 
2,157 pound-equivalent removals, or about 58 pound-equivalents per 
facility. These incremental removals are nearly twice the removals (on 
a per facility basis) than would have been realized by regulating 
industrial laundry and landfill facilities. Because EPA has concluded 
that the proposed option is feasible and achievable, and POTW burden 
would not be reduced with a flow cutoff, EPA is not proposing a flow 
cutoff for the Steel Forming and Finishing subcategory. However, EPA 
solicits comment on flow cutoffs at the 1, 2, and 3 MGY levels. Under 
these scenarios, existing regulations in 40 CFR part 420 would continue 
to apply to the excluded facilities. Unlike the facilities in the Metal 
Finishing Job Shops or Printed Wiring Board subcategories, the 
facilities in the MP&M Steel Forming & Finishing subcategory are 
covered in their current regulations as parts of several subcategories, 
thus creating problems for control authorities in implementing the 
appropriate requirements. EPA solicits comment on implementation and 
market consequences of these options. Table XII.C-1 above shows the 
pounds of pollutants removed by the proposed option, and Table XII.C-2 
summarizes the costs and economic impacts associated with the proposed 
option.
3. Calculation of PSES
    Based on the results of the pass-through analysis discussed in 
Section XII.H.1., EPA is proposing pretreatment standards for existing 
sources in the Steel Forming and Finishing subcategory equivalent to 
those limitations proposed for BAT for the pollutants listed at 
Sec. 438.55 (as provided in the codified regulation that accompanies 
this preamble). EPA determined that all of the pollutants listed in 
Sec. 438.55 (except for Total Sulfide, TOC, and TOP) pass through 
POTWs. EPA is proposing a limitation for total sulfide based on 
potential POTW interference or upset associated with discharges of 
total sulfide from MP&M facilities. EPA is proposing limitations for 
TOC and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXI.C for a discussion of monitoring 
flexibility.)
4. Compliance Date
    EPA is proposing to establish a three-year deadline for compliance 
with PSES. Design and construction of systems adequate for compliance 
with PSES will be a substantial undertaking for many MP&M sites.

I. Oily Wastes Subcategory

1. Need for PSES
    As discussed in Section XII.A, two of the factors that EPA uses to 
determine the need for pretreatment standards is whether the pollutants 
discharged by an industry pass through or interfere with a POTW. For 
the Oily Wastes subcategory, EPA is proposing pretreatment standards 
equivalent to BAT for the following three pollutants or pollutant 
parameters: TOC, TOP and total sulfide.
2. Selected PSES Option
    As discussed in Section XII.B, in the Agency's engineering 
assessment of the best available technology for pretreatment of 
wastewater from the Oily Wastes Subcategory, EPA considered the same 
technology options for PSES as it did for BAT with the additional 
consideration of a flow cutoff exclusion. The Agency is proposing BAT 
Option 6 with a 2 MGY flow cutoff for PSES. The Agency is proposing 
Option 6 for PSES for many of the same reasons it selected that option 
for BPT and BAT (See Section IX.F and XI.F) and provides additional 
rationale below. EPA is proposing the 2 MGY flow cutoff primarily to 
reduce the burden on POTWs, and solicits comment on a 3 MGY cutoff as a 
possible alternative to further reduce impacts.
    EPA determined that Option 6 represented the best available 
technology and that Option 6 with a 2 MGY flow cutoff was economically 
achievable and greatly reduced the burden on POTWs. This option results 
in 14 facility closures (less than 1 percent of the indirect 
discharging Oily Wastes subcategory population). See Section XVI.E for 
a discussion on job losses. Additionally, the Agency believes that 
Option 6 represents the ``best available'' technology as it achieves a 
high level of pollutant control, treating all priority pollutants to 
very low levels, often at or near the analytical minimum level. 
According to EPA's detailed questionnaires, approximately 44 percent of 
the indirect discharging facilities in the Oily Wastes subcategory 
employ oil-water separation by chemical emulsion breaking followed by 
gravity separation and oil skimming (Option 6) while no facilities 
employ ultrafiltration (Option 8).
    EPA did evaluate BPT Option 8 with a 2 MGY flow cutoff as a basis 
for establishing PSES more stringent than the level of control being 
proposed

[[Page 470]]

today. EPA estimates that the economic impact due to the additional 
controls at Option 8 levels would result in the same number of facility 
closures (14) as Option 6. Therefore, EPA does consider Option 8 to be 
economically achievable for this subcategory. However, based on the 
available data base, EPA is not proposing to establish PSES limitations 
based on Option 8 because it removes fewer pound-equivalents than 
Option 6. Therefore, the Agency determined that Option 6 is the ``best 
available'' technology economically achievable for the removal of 
priority pollutants from wastewater generated at Oily Wastes 
subcategory facilities.
    Considering the large number of indirect dischargers which have the 
potential to be covered by this proposed regulation, an important issue 
to the affected industry and to permit writers is the potentially 
enormous administrative burden associated with issuing permits or other 
control mechanisms for all these facilities. Therefore, in developing 
this proposal, EPA has looked for means of reducing the administrative 
burden, reducing monitoring requirements, and reducing reporting 
requirements. In order to meet this end, the Agency is proposing a 2 
MGY flow cutoff for the Oily Wastes subcategory. Under this proposed 
option, facilities in the Oily Wastes subcategory that discharge 
greater than 2 MGY per year of MP&M process wastewater would be subject 
to the proposed pretreatment standards. However, those facilities in 
the Oily Wastes subcategory that discharge 2 MGY or less would not be 
subject to MP&M PSES requirements. These facilities would, however, 
remain subject to the existing general pretreatment standards at 40 CFR 
Part 403.
    The Agency is proposing the 2 MGY flow cutoff exclusion for the 
Oily Wastes subcategory based on several factors. First, and the most 
important factor, was the overall size of the Oily Wastes subcategory. 
EPA estimates that there are approximately 28,500 indirect discharging 
facilities in the Oily Wastes subcategory, of which over 99 percent are 
not currently regulated by categorical pretreatment standards. 
Establishing an MP&M pretreatment standard for all 28,500 facilities 
would nearly double the number of permits that local authorities are 
currently responsible for. EPA concluded that this increased permit 
burden was not reasonable given the projected loadings reductions and 
therefore explored potential flow cutoffs as a way to reduce the impact 
on POTW permitting authorities.
    Second, EPA is proposing the 2 MGY flow cutoff for this subcategory 
based in part on the small number of pound-equivalents that would be 
removed by facilities with annual wastewater flows less than or equal 
to 2 MGY. EPA determined that after removing facilities that close in 
the baseline (``baseline closures'') from the analysis, over 99 percent 
of the indirect discharging facilities in the Oily Wastes subcategory 
discharge less than or equal to 2 MGY. EPA estimates average removals 
of only 2 pound-equivalents per facility per year for these facilities.
    In addition, EPA determined that for those facilities in this 
subcategory that discharge between 1 and 2 MGY the MP&M regulation 
would remove an average of 31 pound-equivalents per year per facility. 
These reductions, as discussed previously, are lower than those 
projected for industrial laundries and landfills, for which EPA 
determined national regulation was not warranted. The Agency concluded 
that regulation of facilities discharging only 2 pound-equivalents per 
year (with those discharging between 1 and 2 MGY at 31 pound-
equivalents per year) was not justified by the additional permitting 
burden associated with these facilities. EPA believes this approach 
would allow Control Authorities to focus their efforts on the 
facilities discharging the vast majority of the pollutants, rather than 
dissipating their limited resources on sites contributing much less to 
the overall problem. EPA does note, however, that the indirect 
discharging facilities that discharge less than or equal to 2 MGY are 
responsible for an estimated 78 percent of the total pound-equivalents 
currently discharged (approximately 51,000 of the 65,000 pound-
equivalents discharged after removing baseline closures from the 
analysis).
    EPA also closely evaluated Option 6 with a 3 MGY flow cutoff for 
the Oily Waste subcategory. Based on EPA's data collection efforts, 
after removing facilities that close in the baseline (``baseline 
closures'') from the analysis, over 99 percent of the indirect 
discharging facilities in the Oily Wastes subcategory discharge less 
than or equal to 3 MGY. The Agency determined that after removing 
baseline closures from the analysis there are approximately 64 indirect 
discharge facilities in this subcategory between 2 and 3 MGY and that 
they discharge an average of 24 pound-equivalents per year per 
facility. If EPA proposed Option 2 with a 3 MGY flow cutoff, the 
economic impacts would decrease slightly (12 facility closures rather 
than 14 at the proposed option). The Agency concluded that the 3 MGY 
flow cutoff was not necessary to reduce POTW burden for the Oily Wastes 
subcategory although it would reduce the economic impact somewhat. EPA 
solicits comment on a 3 MGY cutoff, but notes that these approximately 
28,160 facilities are responsible for an estimated 81 percent of the 
total pound-equivalents currently discharged (approximately 52,500 of 
the 65,000 pound-equivalents discharged after removing baseline 
closures from the analysis).
    Therefore, EPA is proposing the 2 MGY flow cutoff but is also 
seriously considering a 3 MGY cutoff. EPA believes this approach would 
allow Control Authorities to focus their efforts on the facilities 
discharging the vast majority of the pollutants, rather than 
dissipating their limited resources on sites contributing much less to 
the overall problem. Table XII.C-1 above shows the pounds of pollutants 
removed by the proposed option, and Table XII.C-2 summarizes the costs 
and economic impacts associated with the proposed option (both tables 
include facilities that close in the baseline). EPA's methodology for 
identifying baseline closures is discussed in Section XVI.
3. Calculation of PSES
    Based on the results of the pass-through analysis discussed in 
Section XII.I.1., EPA is proposing pretreatment standards for existing 
sources in the Oily Wastes subcategory equivalent to those limitations 
proposed for BAT for the pollutants listed at Sec. 438.65 (as provided 
in the codified regulation that accompanies this preamble). EPA is 
proposing a pretreatment standard for total sulfide based on potential 
POTW interference or upset associated with discharges of total sulfide 
from MP&M facilities. EPA is proposing pretreatment standards for TOC 
and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXI.C for a discussion of monitoring 
flexibility.)
4. Compliance Date
    EPA is proposing to establish a three-year deadline for compliance 
with PSES. Design and construction of systems adequate for compliance 
with PSES will be a substantial undertaking for many MP&M sites.

J. Railroad Line Maintenance Subcategory

1. Rationale for Not Proposing PSES
    EPA is proposing to not establish PSES for the Railroad Line 
Maintenance subcategory based on the small quantity

[[Page 471]]

of toxic pollutants discharged by facilities in this subcategory. The 
Agency estimates that there are 799 indirect discharging railroad line 
maintenance facilities that currently discharge 1,800 pound-equivalents 
per year to our nation's waters (taking into account removals at the 
POTW), or just over 2 pound-equivalents per facility per year. Based on 
this analysis, EPA preliminarily concluded that there is no need to 
develop nationally applicable regulations for this subcategory due to 
the low levels of pollutants discharged by facilities in this 
subcategory.

K. Shipbuilding Dry Dock Subcategory

1. Rationale for Not Proposing PSES
    EPA is proposing to not establish PSES for the Shipbuilding Dry 
Dock subcategory based on the small number of facilities in this 
subcategory and on the small quantity of toxic pollutants removed by 
the technology options evaluated by EPA for this proposal. The Agency 
estimates that there are 6 indirect discharging facilities that have 
one or more dry docks that currently discharge 852 pound-equivalents 
per year to our nation's waters (taking into account removals at the 
POTW). On a national basis, Option 8 (ultrafiltration + P2) removed 
less than 1 pound-equivalent per year while Option 10 (DAF plus P2) 
only removed 26 pound-equivalents per year (or less than 5 pound-
equivalents removed per facility per year). The Agency estimates that 
all of these facilities currently have DAF treatment in place. EPA 
determined that nationally-applicable regulations are unnecessary at 
this time because of the small number of facilities in this subcategory 
and based on the small amount of toxic pounds removed by the technology 
options evaluated by the Agency. The Agency believes that pretreatment 
local limits implemented on a case-by-case basis can more appropriately 
address any individual toxic parameters present at these six 
facilities.

XIII. New Source Performance Standards (NSPS) and Pretreatment 
Standards for New Sources (PSNS)

    Section 307(c) of the Act calls for EPA to promulgate pretreatment 
standards for new sources (PSNS) at the same time that it promulgates 
new source performance standards (NSPS). New facilities have the 
opportunity to incorporate the best available demonstrated technologies 
including process changes, in-plant controls, and end-of-pipe treatment 
technologies.
    The same technologies discussed previously for BAT and PSES are 
available as the basis for NSPS and PSNS. Since new sites have the 
potential to install pollution prevention and pollution control 
technologies more cost effectively then existing sources, EPA strongly 
considered the more advanced treatment options for NSPS and PSNS. The 
Agency discusses its analysis of these more stringent options for NSPS 
and PSNS on a subcategory-by-subcategory basis below.

A. NSPS for the General Metals Subcategory

1. Need for NSPS
    EPA expects that new facilities in the General Metals subcategory 
will discharge similar quantities of the same pollutants that existing 
sources discharge. Therefore, the need for NSPS regulation is the same 
as the need for BPT regulation. (See Section IX.A.1).
2. Selected NSPS Option
    EPA is proposing New Source Performance Standards for this 
subcategory based on BAT Option 4. The Agency determined that Option 4 
is the best available demonstrated technology for the removal of 
pollutants in this subcategory. EPA's analytical data shows that Option 
4 is capable of achieving much lower long-term averages than Option 2 
for several of the metal pollutants of concern. In addition, EPA's data 
shows that microfiltration greatly reduces the variability in the 
concentration of the metal pollutants in the treatment effluent. 
Although Option 4 costs $54,500 (1996$) more than Option 2 annually for 
a new facility with a wastewater flow of 1.1 MGY (the wastewater flow 
for a representative direct discharging facility in the General Metals 
subcategory), EPA is proposing Option 4 because of the lower levels of 
metal pollutants in the wastewater effluent. EPA noted in the 
discussion of its consideration of this technology for BPT/BAT that it 
is not being proposed for BPT because the additional removals, while 
large when considered across the entire population of existing 
facilities, were not significant on a per facility basis, and because 
of concerns with potential increased loadings (relative to Option 2) of 
COD and organic pollutants. EPA requests comment on basing NSPS on 
Option 2 for the same reasons it is proposing to base BPT/BAT on Option 
2.
    The Agency also strongly considered proposing NSPS based on 
ultrafiltration for oil and grease removal and chemical precipitation 
followed by sedimentation for TSS and metals removal. This option is 
equivalent to BAT Option 2 with the oil/water separator replaced by an 
ultrafilter. The Agency is soliciting comment and data on this NSPS 
option for the final rule.
3. Calculation of NSPS Limitations
    The Agency is proposing NSPS limitations for all of the pollutants 
that it proposed BPT and BAT limitations for in this subcategory. The 
NSPS limitations for this subcategory can be found in the proposed rule 
(which accompanies this preamble) at Sec. 438.16. (See Section XXI.C. 
for a discussion of monitoring flexibility.) EPA based these proposed 
regulations on EPA sampling episodes at four facilities that employed 
Option 4 technologies. Three of the four facilities are General Metals 
facilities while the fourth is a printed wiring board manufacturer. The 
Agency used the same statistical methods for determining the effluent 
limitations for NSPS as it described in Section VIII. Because of the 
limited number of facilities that EPA has analytical sampling data on 
for Option 4, the Agency is soliciting comment and data on Option 4 
technologies. Specifically, the Agency is interested in wastewater 
treatment data from MP&M facilities employing Option 4 technologies 
(ultrafiltration for oil and grease removal and microfiltration 
following chemical precipitation for removal of TSS and metals). See 
Section XXIII ``Solicitation of Comments.''
4. NSPS Analysis
    The Agency also performed an economic analysis in order to 
determine if Option 4 presented a barrier to entry for new facilities 
in the General Metals subcategory. EPA determined that the cost of 
compliance with NSPS based on Option 4 would make up only 0.04 percent 
of a new facility's projected revenues. Therefore, EPA concluded that 
NSPS based on Option 4 would not create a barrier to entry.

B. PSNS for the General Metals Subcategory

1. Need for PSNS
    EPA expects that new facilities in the General Metals subcategory 
will discharge similar quantities of the same pollutants that existing 
sources discharge. Therefore, the need for PSNS regulation is the same 
as the need for PSES regulation. (See Section XII.D.1).
2. Selected PSNS Option
    EPA is proposing Pretreatment Standards for New Sources for this 
subcategory based on BAT Option 4 for the same reasons it is proposing 
this option for NSPS. EPA is also requesting comment on basing PSNS on 
Option 2, as with NSPS. In addition, EPA is

[[Page 472]]

proposing a 1 MGY flow cutoff exclusion for PSNS. This is the same flow 
cutoff level that EPA is proposing for PSES for the existing indirect 
discharging facilities in the General Metals subcategory. The Agency 
concluded that a 1 MGY flow cutoff is appropriate for new indirect 
discharging facilities in the General Metals subcategory based on the 
potential POTW permitting burden that would be associated with 
developing and then maintaining permits for new sources with low flows 
and the likelihood that these facilities discharge a small amount of 
pound-equivalents at these low flow rates. The Agency assumes that the 
pound-equivalents removed per facility for new facilities with flows 
below or equal to 1 MGY would be even lower than the 22 pound-
equivalents per facility for similarly sized existing sources in this 
subcategory. The Agency concluded that a similar (or even smaller) 
amount of pollutant removal is not significant and does not justify 
regulation of these facilities by a national categorical regulation. 
EPA solicits comment on whether it is appropriate to exclude new 
sources that discharge process wastewater equal to 1 million gallons or 
less for the reasons described above.
    The Agency also strongly considered proposing PSNS based on 
ultrafiltration for oil and grease removal and chemical precipitation 
followed by sedimentation for TSS and metals removal. This option is 
equivalent to BAT Option 2 with the oil/water separator replaced by an 
ultrafilter. The Agency is soliciting comment and data on this PSNS 
option for the final rule.
3. Calculation of PSNS Limitations
    The Agency is proposing PSNS limitations for the same pollutants 
that it proposed PSES regulations. The PSNS limitations for this 
subcategory can be found in the proposed rule (which accompanies this 
preamble) at Sec. 438.17. EPA determined that all of the pollutants 
listed in Sec. 438.17 (except for Total Sulfide, TOC, and TOP) pass 
through POTWs. EPA is proposing a limitation for total sulfide based on 
potential POTW interference or upset associated with discharges of 
total sulfide from MP&M facilities. EPA is proposing limitations for 
TOC and TOP as part of a compliance alternative for organic pollutant 
discharges. (See Section XXI.C. for a discussion of monitoring 
flexibility.) The Agency based these proposed limitations on the same 
four EPA sampling episodes that EPA discussed in Section XIII.A.3.
4. PSNS Analysis
    Like NSPS, the Agency determined that the cost of compliance with 
PSNS based on Option 4 would make up only 0.09 percent of a new 
facility's projected revenues and concluded that this would not create 
a barrier to entry.

C. NSPS for the Metal Finishing Job Shops Subcategory

1. Need for NSPS
    EPA expects that new facilities in the Metal Finishing Job Shops 
subcategory will discharge similar quantities of the same pollutants 
that existing sources discharge. Therefore, the need for NSPS 
regulation is the same as the need for BPT regulation. (See Section 
IX.B.1).
2. Selected NSPS Option
    EPA is proposing New Source Performance Standards for this 
subcategory based on BAT Option 4. The Agency determined that Option 4 
is the best available demonstrated technology for the removal of 
pollutants in this subcategory. EPA's analytical data shows that Option 
4 is capable of achieving much lower long term averages than Option 2 
for several of the metal pollutants of concern. In addition, EPA's data 
shows that microfiltration greatly reduces the variability in the 
concentration of the metal pollutants in the treatment effluent. 
Although Option 4 costs $72,500 (1996$) more than Option 2 annually for 
a new facility with a wastewater flow of 6.0 MGY (the wastewater flow 
for a representative direct discharging facility in the Metal Finishing 
Job Shops), EPA is proposing Option 4 because of the lower levels of 
metal pollutants in the treated wastewater effluent. EPA is not 
proposing Option 4 for BPT for this subcategory because of the lack of 
significant overall pollutant removals achieved, and the fact that it 
removes less COD, O&G, and organic pollutants. EPA requests comment on 
using Option 2 as the basis for NSPS.
    The Agency also strongly considered proposing NSPS based on 
ultrafiltration for oil and grease removal and chemical precipitation 
followed by sedimentation for TSS and metals removal. This option is 
equivalent to BAT Option 2 with the oil/water separator replaced by an 
ultrafilter. The Agency is soliciting comment and data on this NSPS 
option for the final rule.
3. Calculation of NSPS Limitations
    The Agency is proposing NSPS limitations for all of the pollutants 
that it proposed BPT and BAT limitations for in this subcategory. The 
NSPS limitations for this subcategory can be found in the proposed rule 
(which accompanies this preamble) at Sec. 438.26. (See Section XXI.C 
for a discussion of monitoring flexibility.) EPA based these proposed 
regulations on the same four EPA sampling episodes that it used to 
calculate NSPS for the General Metals subcategory. See Section XIII.A.
4. NSPS Analysis
    The Agency also performed an economic analysis in order to 
determine if Option 4 presented a barrier to entry for new facilities 
in the Metal Finishing subcategory. EPA determined that the cost of 
compliance with NSPS based on Option 4 would make up only 1.41 percent 
of a new facility's projected revenues. Therefore, EPA concluded that 
NSPS based on Option 4 would not create a barrier to entry.

D. PSNS for the Metal Finishing Job Shops Subcategory

1. Need for PSNS
    EPA expects that new facilities in the Metal Finishing Job Shops 
subcategory will discharge similar quantities of the same pollutants 
that existing sources discharge. Therefore, the need for PSNS 
regulation is the same as the need for PSES regulation. (See Section 
XII.E.1).
2. Selected PSNS Option
    EPA is proposing Pretreatment Standards for New Sources for this 
subcategory based on BAT Option 4 for the same reasons it is proposing 
this option for NSPS. EPA is also requesting comment on PSNS limits 
based on Option 2. In addition, EPA is not proposing a flow cutoff 
exclusion for PSNS for this subcategory for the same reasons that it 
did not propose a flow cutoff for PSES, but is requesting comment on 
flow cutoffs of 1 and 2 MGY, as with PSES. (See Section XII.E.)
    The Agency also strongly considered proposing PSNS based on 
ultrafiltration for oil and grease removal and chemical precipitation 
followed by sedimentation for TSS and metals removal. This option is 
equivalent to BAT Option 2 with the oil/water separator replaced by an 
ultrafilter. The Agency is soliciting comment and data on this PSNS 
option for the final rule.
3. Calculation of PSNS Limitations
    The Agency is proposing PSNS limitations for the same pollutants 
that it proposed PSES regulations. The PSNS limitations for this 
subcategory can be found in the proposed rule (which accompanies this 
preamble) at Sec. 438.27. EPA determined that all of the pollutants 
listed in Sec. 438.27 (except for Total Sulfide, TOC, and TOP) pass 
through POTWs. EPA is proposing a


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