f/EPA
United States
Environmental Protection
Agency
Effluent Guidelines
Program Plan 14
January 2021
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U.S. Environmental Protection Agency
Office of Water (4303T)
1200 Pennsylvania Avenue, NW
Washington, DC 20460
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Table of Contents
TABLE OF CONTENTS
Page
1. EXECUTIVE SUMMARY 1-1
2. BACKGROUND 2-1
2.1 The Clean Water Act and the Effluent Guidelines Program 2-1
2.2 Effluent Limitations Guidelines and Pretreatment Standards Overview 2-1
2.3 Effluent Guidelines Review and Planning Process 2-3
3. SUMMARY OF PUBLIC COMMENTS RECEIVED ON THE PRELIMINARY EFFLUENT
GUIDELINES PROGRAM PLAN 14 3-1
4. SUMMARY OF ANNUAL REVIEW ACTIVITIES 4-1
5. REVIEWS OF INDUSTRIAL WASTEWATER DISCHARGES AND TREATMENT
TECHNOLOGIES 5-1
5.1 ELG Program Framework 5-1
5.2 Effluent Limitations Guidelines Database 5-1
5.3 Nutrient Discharges in Industrial Wastewater 5-2
5.3.1 Nutrient Discharge Rankings 5-3
5.3.2 Prioritization of PSCs for Further Review from the Nutrient Discharge Rankings
5-7
5.4 Industrial Wastewater Treatment Technology Information in the Industrial Wastewater
Treatment Technology Database 5-9
5.5 Industrial Wastewater Treatment Technologies Reviews 5-9
5.6 Industrial Discharges to Impaired Waters 5-11
5.7 Review of Industrial Wastewater Discharge Monitoring Report Concentration Data.. 5-12
5.7.1 Data Used in the Analysis 5-12
5.7.2 Methodology and Considerations for the Analysis 5-13
5.7.3 Results of the Analysis 5-14
5.7.4 Potential Analysis Refinements 5-17
6. ONGOING ELG STUDIES 6-1
6.1 Detailed Study of the Petroleum Refining Category (40 CFR Part 419) 6-1
6.2 Detailed Study of Electrical and Electronic Components Category (40 CFR Part 469). 6-1
6.3 Study of Oil and Gas Extraction Wastewater Management 6-2
6.4 Study of Per- and Polyfluoroalkyl Industrial Sources and Discharges 6-2
6.5 Study of Meat and Poultry Products Point Source Category (40 CFR Part 432) 6-3
7. ONGOING ELG RULEMAKING 7-1
7.1 Steam Electric Power Generating Point Source Category (40 CFR Part 423) 7-1
8. SUMMARY TABLE OF PLANS FOR EXISTING POINT SOURCE CATEGORIES 8-1
9. REFERENCES FOR PLAN 14 9-1
in
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List of Tables and Figures
LIST OF TABLES
Page
Table 2-1. Statutorily Prescribed Levels of Control 2-2
Table 5-1. Data Sources Used for Nutrients Impaired Waters Analysis 5-6
Table 5-2. WERF Nutrient Removal Methods and Treatment Objectives 5-8
Table 5-3. Preliminary Technology Review Findings 5-10
Table 5-4. Results of the Cross-Category Concentration Analysis 5-15
Table 8-1. Summary of Plans from EPA's Review of Existing Industrial Categories 8-1
LIST OF FIGURES
Page
Figure 5-1. Top Ten PSCs Discharging Total Nitrogen in 2018 5-5
Figure 5-2. Top Ten PSCs Discharging Total Phosphorus in 2018 5-5
iv
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1—Executive Summary
1. Executive Summary
Effluent Guidelines Program Plan 14 (Plan 14) fulfills the requirement in Clean Water Act (CWA)
Section 304(m) to biennially publish a plan for new and revised effluent limitations guidelines, after
public review and comment. EPA published Preliminary Effluent Guidelines Program Plan 14
(Preliminary Plan 14) on October 24, 2019.
Plan 14 provides updates on EPA's reviews of industrial wastewater discharges and treatment
technologies discussed in Preliminary Plan 14 including analyses of industrial sources and discharges of
nutrients, proposed treatment technology reviews, and the effluent limitations guidelines database, and
presents preliminary results from some new analyses.
Plan 14 also provides updates on ongoing point source category (PSC) studies, including EPA's decision
to conclude the Petroleum Refining Category study and planned next steps for the detailed study on the
Electrical and Electronic Components (E&EC) Category. Plan 14 provides an update on the Per- and
Polyfluoroalkyl Substances (PFAS) Multi-Industry study, the scope of which includes Organic
Chemicals, Plastics, and Synthetic Fibers (OCPSF) manufacturers and formulators, airports, rug and
textile manufacturers, pulp and paper manufacturers, and the metal finishing PSC (added to the scope of
the study after the Preliminary Plan 14 was published). Plan 14 describes the types of information
regarding PFAS that have been received to date, that EPA primarily received this information through
outreach to stakeholders, and that EPA continues to evaluate this information to inform decisions about
how best to address industrial PFAS discharges.
Finally, Plan 14 discusses several actions that are included in EPA's Fall Regulatory Agenda, including
revisions to 40 CFR Part 437 to increase flexibility for centralized waste treaters who treat produced
water from oil and gas extraction; initiating an effort to evaluate BAT limitations for two waste streams
(landfill leachate and legacy wastewater) at steam electric power plants, that were addressed in the 2015
Steam Electric Rule, but vacated in an April 2019 decision in U.S. Court of Appeals for the Fifth
Circuit; and an advance notice of proposed rulemaking for the OCPSF PSC to solicit additional
information and data about PFAS manufacturers and formulators.
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2—Background
2. Background
This section explains how the Effluent Guidelines Program fits into EPA's National Water Program,
provides an overview of the Effluent Guidelines Program, and summarizes EPA's procedures for
revising and developing effluent limitations guidelines and standards (ELGs) (i.e., the effluent
guidelines planning process).
2.1 The Clean Water Act and the Effluent Guidelines Program
The CWA is focused on two types of controls for point source discharges of pollutants to waters of the
United States: (1) technology-based controls, based on ELGs and, (2) water quality-based controls,
based on state water quality standards.
The CWA directs EPA to promulgate technology-based ELGs that reflect pollutant reductions
achievable in categories or subcategories of industrial point sources through implementation of available
treatment technologies. 33 U.S.C. 1311(b) and 1314(b). ELGs apply to pollutants discharged from
industrial facilities to surface water (direct discharges) and to publicly owned treatment works (POTWs)
(indirect discharges). EPA's technology-based standards ensure that industrial facilities with similar
characteristics will, at a minimum, meet similar effluent guidelines or pretreatment standards
representing the performance of the "best" pollution control technologies, regardless of their location or
the nature of their receiving water or POTW into which they discharge.
The CWA also gives states the primary responsibility for establishing, reviewing, and revising water
quality standards. Effluent guidelines are not specifically designed to ensure that regulated discharges
meet the water quality standards of the receiving water body. For this reason, while technology-based
ELGs in discharge permits may meet or exceed water quality standards, the CWA also requires EPA and
authorized states to establish water quality-based effluent limitations as stringent as necessary to meet
water quality standards. 33 U.S.C. 1311(b)(1)(C). Water quality-based limits may require industrial
facilities to meet requirements that are more stringent than those in the ELGs.
To date, EPA has promulgated ELGs for 59 industrial categories. See EPA's Industrial Effluent
Guidelines webpaee1 for more information. These ELGs apply to between 35,000 and 45,000 U.S.
direct dischargers, as well as another 129,000 facilities that discharge to POTWs. Based on pollutant
reduction estimates from each ELG, EPA estimates that the regulations altogether prevent the discharge
of over 700 billion pounds of pollutants annually.2
2.2 Effluent Limitations Guidelines and Pretreatment Standards Overview
EPA promulgates technology-based limitations for conventional, toxic, and nonconventional pollutants
in accordance with six statutorily prescribed levels of control (Table 2-1). The limitations are based on
performance of specific technologies, but the regulations do not require use of a specific control
technology to achieve the limits. For more information, see EPA's Learn about Effluent Guidelines
webpaee.3
1 See https://www.epa.gov/eg/indnstrial-efflnent-giiidelines.
2 Estimated from the difference between discharges in each point source category before ELG promulgation and expected
decrease in discharge post promulgation, based on a review of ELG development documents.
3 See https://www.epa.gov/eg/learn-abont-efflnent-gnidelines.
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2—Background
The CWA specifies different levels of control based on the type of pollutant at issue (i.e., conventional,
toxic, or nonconventional). CWA section 304(a)(4) designates the following as conventional pollutants:
biochemical oxygen demand (BOD5), total suspended solids, 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). EPA has identified 65 pollutants
and classes of pollutants as toxic, among which 126 specific substances have been designated by EPA as
priority toxic pollutants (Appendix A to Part 423, reprinted after 40 CFR Part 423.17). All other
pollutants are considered nonconventional.
Table 2-1. Statutorily Prescribed Levels of Control
l.e\ol of
(01H ml
( \\ A Slalulon
UolVivncc
Description
Best
Practicable
Control
Technology
(BPT)
CWA sections
301(b)(1)(A) and
304(b)(1), 33
U.S.C.
1311(b)(1)(A) and
1314(b)(1)
EPA develops effluent limitations based on BPT for conventional, toxic, and
nonconventional pollutants. EPA establishes BPT effluent limitations based on the
average of the best performance of facilities within an industry of various ages,
sizes, processes, or other common characteristics. Where existing performance is
uniformly inadequate, BPT may reflect higher levels of control than currently in
place in an industrial category if the Agency determines that the technology can be
practically applied.
Best
Conventional
Pollutant
Control
Technology
(BCT)
CWA sections
301(b)(2)(E) and
304(b)(4), 33
U.S.C.
1311(b)(2)(E) and
1314(b)(4)
BCT addresses conventional pollutants from existing industrial point sources. EPA
establishes BCT limitations by considering the factors specified in Section
304(b)(4)(B), including a two part "cost-reasonableness" test. This methodology
was published in a Federal Register notice on July 9, 1986 (51 FR 24974).
Best Available
Technology
Economically
Achievable
(BAT)
CWA sections
301(b)(2)(A) and
304(b)(2), 33
U.S.C.
1311(b)(2)(A) and
1314(b)(2)
EPA develops effluent limitations based on BAT for toxic and nonconventional
pollutants. BAT represents the best available economically achievable performance
of plants in an industrial subcategory or categoiy. Factors considered in
establishing BAT include the age of equipment and facilities involved, the process
employed, the engineering aspects of control techniques or process changes, the
cost of achieving such effluent reduction, non-water quality environmental impacts
(including energy requirements), and such other factors as the Administrator deems
appropriate. 33 U.S.C. 1314(b)(2)(B). BAT limitations may be based 011 end-of-
pipe wastewater treatment or effluent reductions attainable through changes in a
facility's processes and operations.
Standards of
Performance
for New
Sources
(NSPS)
CWA section 306,
33 U.S.C. 1316
EPA develops effluent limitations based 011 NSPS for conventional, toxic, and
nonconventional pollutants. NSPS reflect effluent reductions based 011 the best
available demonstrated control technology. 33 U.S.C. 1316(a)(1). In establishing or
revising NSPS. EPA considers the cost of achieving such effluent reduction and
any non-water quality, environmental impact and energy requirements. 33 U.S.C.
1316(b)(1)(B).
Pretreatment
Standards for
Existing
Sources
(PSES)
CWA section
307(b), 33 U.S.C.
1317(b)
EPA develops PSES for nonconventional and toxic pollutants. PSES are national,
uniform, technology-based standards that apply to indirect dischargers. They are
designed to prevent the discharge of pollutants that pass through, interfere with, or
are otherwise incompatible with the operation of POTWs 33 U.S.C. 1317(b)(1).
The Agency considers the same factors for PSES as it does for BAT limitations. 33
U.S.C. 1314(b)(2)(B).
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2—Background
Table 2-1. Statutorily Prescribed Levels of Control
l.e\ol of
(oiH ml
( \\ A Sliilulon
UolVivncc
Description
Standards for
New Sources
(PSNS)
307(c), 33 U.S.C.
1317(c)
uniform, technology-based standards that apply to new indirect dischargers. Like
PSES. they are designed to prevent the discharges of pollutants that pass through,
interfere with, or are otherwise incompatible with the operation of POTWs. PSNS
are issued at the same time as NSPS. 33 U.S.C. 1317(c). The Agency considers the
same factors in promulgating PSNS as it considers in promulgating NSPS. 33
U.S.C. 1316(a)(1).
EPA and states implement ELGs for point sources that discharge pollutants into surface waters through
National Pollutant Discharge Elimination System (NPDES) permits.4 POTWs, states, and EPA enforce
pretreatment standards for point sources that discharge to POTWs.5
2.3 Effluent Guidelines Review and Planning Process
The CWA contains multiple provisions requiring EPA to review and revise the limitations, standards,
and guidelines that apply to new and existing as well as direct and indirect dischargers. To provide
transparency to the public, EPA has initiated the development of a document that will present the
framework and the process that EPA uses to evaluate PSCs, gather information, and otherwise consider
whether to promulgate or revise an ELG.
For existing direct dischargers, those who discharge into navigable waters, the CWA requires EPA to
review effluent limitations "at least every five years and, if appropriate, revise[]" those limitations.6 The
CWA also requires EPA to publish regulations providing "guidelines for effluent limitations, and, at
least annually thereafter, revise, if appropriate, such regulations."7 Historically, rather than conducting
separate reviews, EPA consolidates its review of effluent limitations required under section 301(d) into
its review of ELGs under section 304(b).8
For indirect dischargers, those who discharge to POTWs, the CWA requires EPA "from time to time" to
publish proposed regulations establishing pretreatment standards.9 The CWA also requires EPA to
"review at least annually . . . and, if appropriate, revise guidelines for pretreatment."10
For new sources, both direct and indirect, the CWA requires EPA to "publish (and from time to time
thereafter [] revise) a list of categories of sources, which shall, at the minimum, include . . " and
"propose and publish regulations establishing Federal standards of performance for new sources within
4 See CWA sections 301(a), 301(b), and 402; 33 U.S.C. 1311(a), 1311(b), and 1342.
5 See CWA sections 307(b) and 307(c); 33 U.S.C. 1317(b) and 1317(c).
6 See CWA section 301(d); 33 U.S.C. 1311(d).
7 See CWA section 304(b); 33 U.S.C. 1314(b). See also Our Children's Earth v. EPA, 527 F.3d 842, 848-49 (9th Cir. 2008)
("Sections 304(b) and (m) require an annual review of "guidelines for effluent limitations" applicable to direct dischargers
and revision "if appropriate.").
8 See Our Children's Earth v. EPA, 527 F.3d 842, 849 (9th Cir. 2008) (discussing EPA's processes of combining the reviews
required under sections 301(d) and 304(b)).
9 See CWA section 307(b); 33 U.S.C. 1317(b).
10 See CWA section 304(g); 33 U.S.C. 1314(g).
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2—Background
such category . . "u The CWA further provides that, "[t]he Administrator shall, from time to time, as
technology and alternatives change, revise such standards following the procedure required by this
subsection for promulgation of such standards."12
In the 1987 Amendments to the CWA, Congress added a provision that requires EPA to biennially
publish in the Federal Register a "plan" that "establishes] a schedule for the annual review and revision
of promulgated effluent guidelines," identifies certain categories of sources for which ELGs have not
previously been published, and establishes a schedule for promulgating ELGs for certain categories of
sources for which such guidelines have not previously been published.13 The biennial planning
requirement was enacted after the CWA provisions regarding review and revision of effluent limitations
and ELGs and informs EPA's obligations under those provisions. When read together, these provisions
require EPA to annually review ELGs and revise those guidelines, if appropriate; and to biennially
publish a plan as described above.
While the CWA requires EPA to annually "review" effluent limitations guidelines and pretreatment
guidelines,14 it does not require EPA to make a "yes" or "no" determination every year on whether to
revise the guidelines. The CWA simply requires EPA to "review" the guidelines every year. "Review"
means "to view or see again," "to examine or study again," "to look back on," or "to go over or examine
critically or deliberately."15 Unlike other sections of the CWA where Congress required EPA to
"approve or disapprove"16 or "determine"17 something, Congress simply required EPA to "review" the
guidelines and revise them if appropriate. If Congress intended to mandate EPA to make a "yes" or
"no" determination on whether to revise the guidelines each year, Congress would have expressed that
clearly in the statute.
Congress's 1987 amendments to the CWA support this understanding of EPA's annual obligation to
"review" ELGs. When Congress amended the CWA in 1987 to add the biennial planning requirements,
Congress used the word "review" rather than "approve or disapprove" or "determine" when describing
EPA's annual obligation to evaluate ELGs.18 Congress had an opportunity in these amendments to
impose additional decision-making requirements on EPA's periodic evaluation of ELGs, for example by
requiring EPA to annually "determine" whether to revise the guidelines, but chose not to.
Where Congress intended to impose a specific obligation on EPA, it knew how to specify that in the
statute. For example, in 304(m), Congress was clear that EPA had to promulgate ELGs by a date certain
for newly identified PSCs discharging toxic and nonconventional pollutants that had no ELGs.19 Unlike
the clarity it provided regarding newly identified PSCs, for existing sources, Congress required only
11 See CWA section 306(b)(1); 33 U.S.C. 1316(b)(1).
12 See CWA section 306(b)(1)(B); 33 U.S.C. 1316(b)(1)(B).
13 See CWA section 304(m); 33 U.S.C. 1314(m).
14 See CWA sections 304(b), 304(m)(l)(A), and 304(g); 33 U.S.C. 1314(b), 1314(m)(l)(A), 1314(g).
15 See "Review," Merriam-Webster.com Dictionary, available at https://www.merriam-webster.com/dictionaw/review (last
visited Oct. 2, 2020).
16 See CWA section 304(1)(2); 33 U.S.C. 1314(1)(2).
17 See e.g., CWA section 301(g)(4)(B); 33 U.S.C. 1311(g)(4)(B).
18 See CWA section 304(m)(l)(A); 33 U.S.C. 1314(m)(l)(A).
19 NRDC v. EPA, 542 F.3d 1235 (9th Cir. 2008).
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2—Background
publication of a plan which establishes a schedule for the annual review and revision, if appropriate, of
existing ELGs in accordance with section 304(b) and a process for public comment on the plan.
The review and revise provisions in the CWA are distinct from the review and revise provisions in the
Clean Air Act (CAA). While courts have found that a provision in the CAA requiring EPA to
periodically review and revise National Ambient Air Quality Standards (NAAQS) requires EPA to make
a "yes" or "no" determination as part of the periodic review and revision, that CAA provision is
distinguishable from the review and revise provisions in the CWA.20 The CAA requires EPA to:
Not later than December 31, 1980, and at five-year intervals thereafter, the Administrator shall
complete a thorough review of the criteria published under section 7408 of this title and the
national ambient air quality standards promulgated under this section and shall make such
revisions in such criteria and standards and promulgate such new standards as may be
appropriate in accordance with section 7408 of this title and subsection (b) of this section. The
Administrator may review and revise criteria or promulgate new standards earlier or more
frequently than required under this paragraph.21
Notably, this CAA provision requires EPA to "complete" a "thorough" review within the statutorily
prescribed period. Conversely, the CWA only requires EPA to "review" the relevant limitations and
guidelines within the statutorily prescribed period. The CAA's language requires a process with more
finality and thoroughness than the process the CWA requires.
Similarly, this CAA provision requires EPA to revise the criteria and standards "as may be appropriate"
while the CWA requires EPA to revise effluent limitations and guidelines and pretreatment guidelines
"if appropriate." The CAA's use of "as ... appropriate" implies that EPA will have determined whether
a revision is appropriate by the end the prescribed review period while the CWA's use of "if
appropriate" recognizes that EPA may not have determined whether a revision is appropriate by the end
of the prescribed review period.
The CAA's review and revise language is distinguishable from the review and revise language in CWA
section 304(b) in particular because the CAA does not have a subsequently enacted section like CWA
section 304(m) that provides further direction to EPA on its periodic review obligations under CWA
section 304(b). As noted above, CWA section 304(m) requires EPA to publish a plan for the annual
review and revision, if appropriate, of promulgated ELGs and makes no mention of any requirement to
approve or disapprove or to make any final determination regarding each of the fifty-nine promulgated
ELGs each year. This statutory language does not meet the Supreme Court's admonition that a
mandatory duty must be a "specific, unequivocal command." See Norton v. S. Utah Wilderness
Alliance, 542 U.S. 55, 63 (2004).
The CAA's review and revise provisions are further distinguishable from the CWA's review and revise
provisions due to the timeframes the statutes provide. While the CAA gives EPA five or eight years to
"review and revise" pollutant standards,22 the CWA gives EPA only one year to review the guidelines.
20 See e.g., Environmental Defense Fund v. Thomas, 870 F.2d 892, 899-900 (2nd Cir. 1989) ("we cannot agree with appellees
that the Administrator may simply make no formal decision to revise or not to revise...").
21 Clean Air Act section 109(d)(1); 42 U.S.C. 7409(d)(1) (emphasis added).
22 See e.g., Clean Air Act section 109(d)(1); 42 U.S.C. 7409(d)(1) (requiring EPA to review and revise, as appropriate, air
quality criteria and national ambient air quality standards every five years); Clean Air Act section 112(d)(6); 42 U.S.C.
7412(d)(6) (requiring EPA to review and revise, as necessary, hazardous air pollutant standards every eight years).
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2—Background
A mandatory duty for EPA to complete the analyses necessary to make a "yes" or "no" determination on
whether to revise the guidelines for each of the categories of sources every year should not be ascribed
to EPA in the absence of explicit evidence of such Congressional intent.
To increase transparency and stakeholder awareness, EPA includes in its biennial plans information on
its review of existing effluent limitations guidelines and pretreatment standards and any industries
reviewed for potential development of new effluent guidelines or pretreatment standards.
Plan 14 summarizes public comments received on the Preliminary Plan 14, describes ongoing planning
activities, including projects EPA initiated as part of its 2019 annual review, and presents findings of
EPA's effluent guidelines planning efforts, including PSC studies and ELG rulemakings (U.S. EPA,
2019a).
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3—Summary of Public Comments Received on the Preliminary Effluent Guidelines Program Plan 14
3. Summary of Public Comments Received on the Preliminary Effluent Guidelines
Program Plan 14
EPA published its Preliminary Plan 14 and provided a 30-day public comment period starting on
October 24, 2019 (see 84 FR 57019). EPA received 18 public comment letters23 on the Preliminary Plan
14 representing seven private citizens, six trade associations, and four environmental organizations.
EPA received comments on most of the topics presented in Preliminary Plan 14. See Response to
Comments for the Effluent Guidelines Program Plan 14 for all comment responses (U.S. EPA, 2020a).
The following summarizes the comments and is organized by topic.
Nutrient Review
Some commenters recommended that when considering the need for further actions to address nutrients,
EPA consider the relatively small percentage of total nutrient loadings attributable to any one specific
industrial category when compared to the total of nutrient loadings in the United States, including non-
point sources of nutrients.
One commenter requested that EPA acknowledge the efforts POTWs have taken in attempting to reduce
their associated nutrient discharges.
There were also specific comments on revising the methodology used in analyzing nutrient data and
EPA is in the process of evaluating those comments and revising the methodology as appropriate. See
Section 5.3 for updates on EPA's review of nutrients in industrial discharges.
Several commenters suggested that EPA should revise the existing Meat and Poultry Products ELGs,
because they contend, the existing regulations do not adequately address discharges from this PSC. See
Section 6.5 for updates on EPA's study of this category.
Per- and Polyfluoroalkyl Substance Review
Several commenters supported EPA's efforts to address PFAS in industrial point source wastewater
discharges, including the multi-industry PFAS Study announced in Preliminary Plan 14 and EPA's
PFAS Action Plan.
One commenter requested that EPA include landfills in its detailed study, as they are known indirect
dischargers of PFAS.
A commenter stated that "existing authorities could be better utilized to protect against PFAS
contamination" and that "EPA should utilize these authorities to track PFAS use in commercial and
industrial facilities in order to identify PFAS discharges in the absence of a CWA-approved analytical
method." The commenter suggested that EPA can and should prioritize addressing PFAS at the source
rather than through drinking water regulations that will impact rate payers.
A commenter requested that EPA clarify its review of PFAS in the Organic Chemicals Plastics and
Synthetic Fibers category as the industry is broad and complex. The commenter also indicated that EPA
should consider addressing PFAS chemicals in a substance-specific manner rather than as a class, to
more precisely describe the historical and current PFOA and long-chain PFAS use and manufacturing,
23 One organization submitted a second comment as a replacement to a previous comment submitted during the comment
period. EPA reviewed and responded to the updated version of the comment instead of the initial comment submitted. As
such, the original version of the comment is not included in this count.
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3—Summary of Public Comments Received on the Preliminary Effluent Guidelines Program Plan 14
and to develop validated, reproducible analytical methods to monitor for PFAS in industrial wastewater
discharges before limits can be set.
Another commenter urged "EPA to take steps to develop ELGs for industries discharging or likely to
discharge PFAS in our waters, and to take steps so it can better gather and publicize critical information
regarding PFAS discharges" (e.g., adding PFAS to the list of TRI chemicals).
See Section 6.4 for updates on the PFAS Multi-Industry Study.
Detailed Study of the Petroleum Refining Category
One commenter stated that they "support EPA's conclusion that no further action regarding the Refinery
ELGs is necessary or appropriate."
Another commenter commented that EPA should continue to study refineries in order to consider PFAS
discharges from refineries.
See Section 6.1 for updates on the Petroleum Refining Detailed Study.
Detailed Study of the E&EC Category
EPA received comments encouraging an update to the pretreatment standards for the E&EC PSC
because of changes in the industry since the ELGs for this PSC were issued in 1983.
See Section 6.2 for updates on the detailed study of the E&EC Category.
Oil and Gas Extraction Wastewater Management
One commenter stated that they "support EPA's decision to complete the Study of Oil and Gas
Extraction Wastewater Management Under the Clean Water Act."
Another commenter disagreed with EPA's categorization of this activity as a study, stating that it is "... a
survey of stakeholders to better characterize current management practices as they relate to discharges of
oil and gas extraction wastewater, and potential challenges, benefits, and barriers to altering EPA's
regulations to allow for discharges in a wider array of circumstances."
This commenter also expressed support for site-specific assessments and treatment plans to ensure that
the discharge of produced water does not impact the environment or downstream drinking water
facilities, rather than national rulemaking.
See Section 6.3 for updates on the Oil and Gas Extraction Wastewater Management study.
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4—Summary of Annual Review Activities
4. Summary of Annual Review Activities
The Preliminary Plan 14 discussed two annual reviews, both the 2017 and the 2018 reviews. Plan 14
presents a summary of the 2019 annual review and identifies additional analyses expected to be part of
the 2020 annual review. This section does not discuss detailed studies or rulemakings for specific
industrial categories that are described in subsequent sections.
For the 2017 annual review, Preliminary Plan 14 discussed EPA's cross-industry review of nutrients in
industrial discharges, (Section 3.3), based on the most recent data available at the time of the review,
specifically 2015 discharge monitoring reports (DMR) and Toxics Release Inventory (TRI) data; EPA's
review of PFAS in industrial discharges (Section 3.4) based on 2016 DMR data; EPA's review of
discharges to impaired waters (Section 3.8); and EPA's consideration of economic indicators as a
component to the ELGs review process (Section 3.7). These reviews looked across all existing ELGs,
including relevant data for industries with existing ELGs, and data for some industries that are not
currently regulated by ELGs.
Preliminary Plan 14 also discussed EPA's intention to continue using peer-reviewed information on
industrial wastewater treatment technologies compiled in the Industrial Wastewater Treatment
Technology (IWTT) Database since 2012 (Section 3.5), along with other information sources to review
technologies that could prompt revisions for certain ELGs (Section 3.6). Preliminary Plan 14 also
discussed EPA's activities to construct and populate the ELG Database (Section 3.1). EPA plans to
continue this effort with the goal of including all 59 ELGs in the final database, which should be made
available on EPA's website in Spring 2020.
For the 2018 annual review, EPA expanded the dataset used to review PFAS in industrial discharges to
include 2017 DMR data. At the time that the 2018 review of PFAS discharges was conducted, 2017 was
the most current year of DMRs available.
For the 2019 annual review, Plan 14 describes how EPA expanded the dataset for the cross-industry
review of nutrient discharges to include 2018 DMR data and incorporated the results of its nutrient
estimation tool to rank and prioritize categories for further review (see Section 5.3). EPA also initiated a
cross-category review of 2017 DMR monthly average concentration data for all reported pollutants (see
Section 5.7). As described generally in Section 5 of this Plan 14, EPA also continued development of the
other analyses and tools. At the time the 2019 review of nutrient discharges was conducted, 2018 was
the most current year of DMRs available. Subsequent annual review activities will look at updated
DMRs.
EPA will present its 2020 annual review as part of Preliminary Effluent Guidelines Plan 15 and expects
to expand the dataset for the cross-category review of DMR data to include 2018 data. Results of these
and any additional reviews will be discussed in Preliminary Effluent Guidelines Program Plan 15.
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5. Reviews of Industrial Wastewater Discharges and Treatment Technologies
This section describes EPA's ongoing ELG program planning activities and analyses, listed below, to
identify industrial categories for potential development of new or revised ELGs and summarizes the data
sources and limitations used to complete the reviews. It also presents the findings and next steps for the
associated planning activities. In Preliminary Plan 14, EPA discussed an economic screening analysis
that it may use in the future to prioritize industrial categories for further review. EPA did not receive
comments on this analysis and has not revised the analysis, however it is a tool the Agency may use in
future to when conducting annual reviews. Plan 14 discusses the following actions that EPA has taken.
• Continued developing an ELG Database that will ultimately include information across all
regulated PSCs in a consolidated, searchable database (see Section 5.1).
• Continued a cross-industry review of nutrient discharges in industrial wastewater and
incorporated results from a tool to estimate nutrient discharges from industrial sources that
are underrepresented in readily available datasets (see Section 5.3).
• Continued to compile wastewater treatment technology information in the IWTT Database
and populate the information in the IWTT web application for public use (see Section 5.4).
• Continued to screen, prioritize, and further review specific industrial wastewater treatment
technologies that may be more broadly evaluated as technology options for future studies and
rulemakings (see Section 5.4).
• Continued review of impaired waters, specifically related to nutrients, to determine if specific
industrial sources were contributing to impairments, (see Section 5.6).
• Initiated a cross-category review of monthly average DMR concentration data (see Section 5.7).
5.1 ELG Program Framework
As mentioned in Section 2.3, the CWA contains multiple provisions requiring EPA to review and revise
the limitations, standards, and guidelines that apply to new and existing as well as direct and indirect
dischargers. To provide transparency and clarity to the public and to better explain the discretion that
EPA maintains regarding review of ELGs and its rulemaking schedule, EPA has initiated the
development of a document that will present the framework and the process that EPA uses to evaluate
PSCs, gather information, and otherwise consider whether to promulgate or revise an ELG.
5.2 Effluent Limitations Guidelines Database
EPA has compiled information on its ELGs for the 59 different PSCs24 into a consolidated ELG
Database and is in the process of developing a web-based application to allow the public to query the
information. The database, once publicly available, and ultimately the web application, will facilitate
searching for information within and across ELGs. The database captures information from the Code of
Federal Regulations (CFR) (40 CFR Parts 405 through 471),25 as well as from the technical
development documents supporting promulgated rules. The ELG Database includes the following
information.
24 See EPA's Industrial Effluent Guidelines webpage (https://www.epa.gov/eg/indnstrial-efflnent-giiidelines') for a list of the
59 point source categories.
25 See https://www.eefr.gov/egi-bin/text-
idx?Sl 7a295bbe0feaae8ea6b4b85da954&me=true&tpl=/eefrbrowse/Title40/40tab_02.tpL
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
• Regulations promulgated (e.g., BPT, BAT, BCT, NSPS, PSES and PSNS).
• Applicability of the ELGs, including definitions of any regulated subcategories.
• Waste streams or process operations associated with each regulation.
• Pollutant limitations.
• CFR references to best management practices, monitoring requirements, and narrative
limitations.
• Rule history, including promulgation and revision dates.
• Technology bases for the underlying the regulations.
The database web application provides EPA and the public with consolidated information about the
requirements and development of current existing ELGs. EPA and the public will be able to search the
regulations for a specific PSC or compare regulations across multiple PSCs more quickly,
systematically, and comprehensively.
EPA plans to use this information to more easily compare specific pollutant limitations, and the
associated technology bases, across industries to identify limitations that may be based on outdated
technologies, or limitations developed using less sensitive analytical methods than are now available.
5.3 Nutrient Discharges in Industrial Wastewater
Nutrient pollution is one of the most widespread, costly, and challenging environmental problems
impacting water quality in the United States. Excessive nitrogen and phosphorus in surface water can
lead to a variety of problems, including eutrophication and harmful algal blooms, with impacts on
drinking water, recreation, and aquatic life. A wide range of human activities contribute to nutrient
pollution from both point and nonpoint sources, including stormwater discharges, runoff, leaking septic
systems, fertilizer, atmospheric deposition, and wastewater discharges.
As part of the 2017 and 2018 annual review of ELGs and to more comprehensively screen industrial
wastewater as a source of nutrients, EPA initiated a cross-industry review of publicly available data on
nutrient discharges from industrial PSCs, as described in Preliminary Plan 14 (U.S. EPA, 2019a). For
that review, EPA ranked and prioritized PSCs for further review based on their annual reported
discharges of nutrients in wastewater and developed a method to estimate potential nutrient discharges
from industrial facilities that are likely to discharge nutrients but are not reported in the publicly
available discharge data. EPA then ranked industrial categories by the nutrient loads in their wastewater
discharges. See The EPA's Review of Nutrient in Industrial Wastewater Discharge ("Previous Nutrients
Report") (U.S. EPA, 2019b) for the methodology and results of the nutrients review.
EPA further reviewed sources of nutrients, nutrient wastewater discharges, and typical wastewater
treatment technologies or best management practices used to control nutrient discharges from the top
two ranking categories: Pulp, Paper, and Paperboard (40 CFR Part 430) and Meat and Poultry Products
(40 CFR Part 432). For the review of the Pulp, Paper, and Paperboard PSC, EPA concluded that the
Agency would review this category when additional information becomes available. See Section 4 of the
Previous Nutrients Report for a summary of the Pulp, Paper, and Paperboard category review. For the Meat
and Poultry Products industry, EPA is continuing to study and collect data to fill large data gaps on the
indirect dischargers associated with this industry (U.S. EPA, 2019b). See Section 6.5 for additional
details on this study.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
In support of its 2019 annual review of ELGs, EPA updated and refined the cross-industry review of
nutrient discharges. Specifically, EPA refreshed the nutrient discharge rankings and nutrient estimations
using 2018 DMR data and combined the reported and estimated data to assess the total potential nutrient
discharges from each PSC. Section 5.3.1 briefly summarizes the methods and findings of EPA's current
review of nutrient discharges. To provide additional context for the discharges, EPA also began
analyzing industrial discharges to nutrient impaired waters as described in Section 5.3.1.2. For
additional details on the methodology and analyses completed for the current nutrients review, see
EPA's Review of Nutrients in Industrial Wastewater Discharge ("Current Nutrients Report") (U.S. EPA,
2020b). Section 5.3.2 presents the prioritization of PSCs for further review of nutrients in industrial
wastewater discharges.
5.3.1 Nutrient Discharge Rankings
For the 2019 cross-industry review of nutrients, EPA used 2018 publicly available data to screen
industrial categories based on reported and estimated total nitrogen and total phosphorus loads
discharged to receiving waters. The goal of this review was to identify additional industries with
potentially greater nutrient loads relative to other PSCs and prioritize for further review those PSCs that
may be candidates for controlling nutrient discharges through ELGs development or revision.
Consistent with its previous cross-industry review of nutrients, EPA downloaded and analyzed 2018
DMR data from EPA's Water Pollutant 1 ogling Tool (Loading Tool).26'27 Data from the Loading Tool
were used since it provides facility-level total nitrogen and phosphorus data from the raw ICIS-NPDES
DMR data. The ICIS-NPDES flow and concentration data, which is certified to be accurate from the
facility, is reported at the outfall level in a variety of forms according to individual permit conditions.
For example, the nutrient parameters reported in DMRs vary by industry and NPDES permit and may
include total nitrogen, ammonia, nitrate, phosphate, total phosphorus and/or other nitrogen or
phosphorus species. See Section 2.1.3.1 in the Previous Nutrients Report for a detailed discussion of the
DMR nutrient aggregation methodology (U.S. EPA, 2019b). These annual total nitrogen and total
phosphorus loads were grouped by PSC as described next.
Individual facility data are commonly reported by Standard Industrial Classification (SIC) or North
American Industry Classification System (NAICS) code rather than PSC, so EPA used established
crosswalks within the Loading Tool to match individual facility data to the most appropriate PSC or
potential PSC based on the facility's reported SIC or NAICS code. EPA then grouped the discharge data
by PSC. See Section 3 of the Loading Tool Technical Users Document for more information on these
crosswalks (U.S. EPA, 2012). EPA summed the reported facility aggregated total nitrogen and total
phosphorous loads in each PSC to calculate a reported total nitrogen and total phosphorous load by
category. This is the same methodology used in Preliminary Plan 14. To provide additional context for
the reported discharges, EPA used the load and flow reported by each facility to calculate the range of
total nitrogen and total phosphorus concentrations discharged by facilities in each PSC.
So far, we have described the processing of reported data (reported in DMRs). Next, EPA estimated
nutrient loadings for facilities that did not report nutrient data. Reported DMR data are only available for
26 See https://echo.epa.gov/trends/loading-tool/water-poHntion-search.
27 Because the nutrient discharge rankings methodology specifically includes an analysis of concentration data, EPA did not
use TRI data, which only includes reported annual loadings, for this review. Additionally, Emergency Planning and
Community Right-to-Know Act (EPCRA) Section 313 Chemical List only includes the following nutrient parameters:
ammonia, nitrate compounds, and yellow or white phosphorus compounds.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
pollutants specified in the facilities' NPDES permits. Currently, only 14 of the 59 ELGs contain
technology-based limitations for nitrogen and/or phosphorus (11 for nitrogen parameter only, one for
phosphorus parameter only, and two for both nitrogen and phosphorus) (U.S. EPA, 2019b).28 Facilities
may also have permit limits for nutrients to meet specific water quality standards or requirements.
Overall, the limits included in facility permits for nutrients vary widely. As presented in Preliminary
Plan 14, EPA developed the Nutrient Estimation Tool (Nutrient Tool) to fill gaps in the available
industrial nutrient wastewater discharge data. The Nutrient Tool identifies and estimates nutrient
discharges for industries whose nutrient discharges may be underrepresented in the DMR dataset. See
Section 5.1 of EPA's previous Nutrients Report for a discussion of the data sources and methodology of
the Nutrient Tool (U.S. EPA, 2019b).29
The Nutrient Tool uses known nutrient discharge data within defined industrial sectors or subsectors
(based on SIC codes), as reported on DMRs, to estimate nutrient discharges for facilities within that
sector or subsector that do not have reported nutrient discharges but based on their industrial
classification are presumed likely to discharge nutrients. The estimation considers, within each SIC
code, elements such as the median nutrient concentration and flow, as well as the percent of facilities
within the SIC code that have reported discharges. The actual discharges may be somewhat higher or
lower than estimated because this estimate is based on a median concentration.
EPA added the estimated and reported total nitrogen and total phosphorous loads for each PSC and
ranked the categories based on the total reported plus estimated load (calculated using the Nutrient
Tool). EPA also calculated the range of concentrations across the combined reported and estimated data
sets.
5.3.1.1 Nutrient Discharge Rankings Results
The nutrient discharge rankings results based on the 2018 DMR data show that industrial facilities
reported discharges of more than 205,000,000 pounds of total nitrogen and 25,500,000 pounds of total
phosphorous to surface waters. With the Nutrient Tool EPA estimated that industrial facilities may have
discharged an additional 215,000,000 pounds of total nitrogen and 128,000,000 pounds of total
phosphorus directly to surface waters in 2018 (ERG, 2020a and 2020b).
Figure 5-1 and Figure 5-2 below present the percent allocation of total discharged load (reported and
estimated) of total nitrogen and total phosphorus, respectively, by the top ten PSCs. Section 5.3.2
discusses EPA's prioritization of PSCs for further review based on the nutrient discharge rankings. See
the Nutrients Report for a detailed breakout of reported and estimated discharge load (ERG, 2020a and
2020b).
28 EPA did not include PSCs with requirements that include zero discharge of pollutants.
29 The Nutrient Tool includes discharges of total nitrogen, ammonia (as N), nitrate (as N), total phosphorus, and phosphate
(as P). The Tool does not use data from the TRI because TRI data do not include underlying pollutant concentrations or
wastewater flows.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
Metal Finishing All other industries
10.600.000 lbs/yr 50.500.000 lbs/yr
3% 12°/
Organic Chemicals, Plastics and
Synthetic Fibers
14.100.000 lbs/yr
3%
Explosives
Manufacturing
18,700.000 lbs/jr
4%
Steam Electric Power
Generating
30,100.000 lbs/yr
7%
Drinking Water Treatment
31,300,000 lbs/yr
8%
Meat and Poultry Products
39.200.000 lbs/yr
9%
Construction and Development
71.400,000 lbs/yr
17%
Hospital
66.100,000 lbs/yr
16%
Pulp, Paper and Paperboard
44,900.00 lbs/yr
11%
Gum and Wood Chemicals Manufacturing
42,800.000 lbs/yr
10%
Figure 5-1. Top Ten PSCs Discharging Total Nitrogen in 2018
Steam Electric Power Generating
3.180.000 lbs/yr
2%
Metal Finishing
3.440.000 lbs/yr
2%
Organic Chemicals, Plastics
aud Synthetic Fibers
5,410.000 lbs/yr
4%
Pulp. Paper and Paperboar d
7.250.000 lbs/yr
5%
Plastics Molding and Forming
7.280.000 lbs/yr
5%
Mineral Mining and Processing
7.880.000 lbs/yr
5%
All other industries
18.900.000 lbs/yr
12%
Meat and Poultry Products
42.200,000 lbs/yr
27%
Hospital
.000.000 lbs/yr
16%
Construction and Development
14.500.000 lbs/yr
9%
Iron and Steel Manufacturing
19.600.000 lbs/yr
13%
Figure 5-2. Top Ten PSCs Discharging Total Phosphorus in 2018
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
5.3.1.2 Assessing Industrial Discharges to Waters Impaired for Nutrients
As part of this cross-industry nutrients review, EPA began evaluating impaired waters data to identify
PSCs potentially discharging nutrients to nutrient impaired waters. This analysis aims to provide
additional context on the potential impact of nutrient discharges from prioritized PSCs. Table 5-1
summarizes the datasets used for this analysis.
Table 5-1. Data Sources Used for Nutrients Impaired Waters Analysis
Diilii Sou i cos
Brief Description
1 so in Impiiiivd \\ aloi s
\nal\sis
ICIS-NPDES
ICIS-NPDES is an information management system
maintained by EPA's Office of Compliance to track permit
compliance and enforcement status of facilities regulated by
NPDES under the CVVA. ICIS-NPDES contains permit and
discharge monitoring information, including the location of
facilities and outfalls.
EPA compiled a list of facility
and outfall locations reported by
all NPDES permitted facilities in
2017 and DMR discharge data
reported in 2018.
National Hydrography
Dataset Plus (NHD
Plus) (Version 2.1)
NHD Plus is a national geospatial surface water framework.
It is a geospatial dataset that, among other things, contains
shapefiles and attribute data for all hvdrologic features in a
given area. In the NHD Plus data, each body of water in the
U.S is split into smaller subsections and assigned an
identifying code called the Reach code.
EPA used the NHD dataset in
order to associate the facility
outfall (or facility location in the
absence of specific outfall
locations) to the nearest water
body segment using the Reach
code.
Assessment and Total
Maximum Daily Load
Tracking and
Implementation
System (ATTAINS)
ATTAINS is an online system for accessing information
about the conditions in the nation's surface waters. The
CVV A requires states, territories, and authorized tribes
(states for brevity) to monitor water pollution and report to
EPA every two years on the waters they have evaluated.
This process is called assessment. This information reported
to EPA by states is available in ATTAINS. The public
information is made available via ATTAINS web services,
geospatial services, as well as through other EPA tools
including "How's My Waterway", and "Envirofacts."
EPA used ATTAINS data to
identify the impairment status and
causes, if applicable, associated
with Reach codes. For this
analysis. EPA considered a water
to be nutrient impaired if the
impairment cause was one or
more of the following: algal
growth, ammonia, nutrients, or
oxygen depletion.
EPA counted the number of facilities discharging nutrients where at least one outfall is discharging to
waters impaired for algal growth, ammonia, nutrients, or oxygen depletion. The location of facilities and
outfalls were based on the permit data in the ICIS-NPDES database, and the surface water impairment
was based on the ATTAINS dataset. EPA then calculated the percent of facilities in each industry that
may be discharging to waters impaired for nutrient-related causes using the following approach:
1. From the 2018 DMR data, EPA summed all reported total nitrogen and total phosphorus
loads for each PSC.
2. EPA calculated the reported total nitrogen and total phosphorus loads for facilities in each
PSC that may be discharging to nutrient impaired waters.
3. EPA divided the load from facilities that may be discharging to nutrient impaired waters
from step 2 by the total load discharged from each PSC from step 1 to calculate the percent
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
of the PSC's total nitrogen and total phosphorus load that is likely discharged to nutrient
impaired waters.
EPA has identified the following considerations regarding the analysis.
• For this analysis, if a facility's outfall location information was not available in ICIS-
NPDES, EPA used the facility's location to determine the National Hydrography Dataset
Plus (NHD Plus) reach that is closest to the facility. Thus, some discharge locations and
receiving waters may be incorrectly identified, affecting the accuracy of estimated discharge
loads into impaired waters.
• Although required to report impaired waters in ATTAINS every two years, the most recent
reporting year varies by state. Some of the data are from as far back as 2002. Furthermore,
many states do not monitor or assess all waters within their boundaries for impairments,
resulting in incomplete data concerning waters impaired by nitrogen and phosphorus
pollution in these states.
• ATTAINS data also do not include coastal regions and Great Lakes waterbodies.30
EPA used the results of this analysis to provide additional context when prioritizing PSCs for further
review (see Section 5.3.2).
5.3.2 Prioritization of PSCs for Further Review from the Nutrient Discharge Rankings
In order to prioritize PSCs for further review, EPA reviewed PSCs whose summed total load (reported
and estimated) makes up 95 percent of the total nitrogen and total phosphorous load, respectively, in
2018 across all PSCs, see the Current Nutrients Report (U.S. EPA, 2020b). EPA did not review facilities
from categories where the ELGs were promulgated or revised in the past seven years: Construction and
Development (Revised March 6, 2014), Steam Electric Power Generating (Revised 2020), Oil and Gas
Extraction (Revised June 2016), and Dental Office (Promulgated June 14, 2017).
For the top PSCs, EPA reviewed the total load across the PSC to determine if the majority of the load is
associated with multiple facilities (hereafter referred to as widespread). EPA did not prioritize PSCs that
have high annual loads due to discharges from less than three facilities, which may not be representative
of discharges across the category. For a breakdown of estimated and reported loads, see the Current
Nutrients Report (U.S. EPA, 2019b).
To provide context for the magnitude of the discharges and facilitate EPA's further prioritization of
PSCs, EPA then compared the range of reported concentrations for each PSC to wastewater treatment
levels associated with varying degrees of nutrient removal obtainable with current technology. The
levels include no nutrient removal with effluent TN greater than 15 mg/L at Level 1 up to Level 5 with
TN less than 2 mg/L (WERF, 2011, U.S. EPA, 2015). For this review, EPA compared 2018 DMR
median and third quartile concentration value (i.e., 50 percent and 75 percent of facilities, respectively)
to Level 2 (the least stringent treatment objective targeting nutrients) and Level 5 (the most stringent
treatment objective targeting nutrients). Table 5-2 describes these treatment levels. Additionally, EPA
compares PSC concentrations to nutrient levels achieved in POTWs using biological nutrient removal
30 See EPA's Waters Assessed as Impaired due to Nutrient-Related Causes for a more detailed discussion of this.
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(BNR) processes. BNR levels of technology are the same as level 4, at 3 mg N/L and 0.1 mg P/L
(Jeyanayagam, 2005).
Table 5-2. WERF Nutrient Removal Methods and Treatment Objectives
I rOillllHMII I.OC'I
Nutrient Riino\al Mechanism
1 iviilimwil Ohjoc(i\os
Total Nitrogen
1 oliil
Phosphorous
Level 2
Nitrification/Denitrification and Biological
Phosphorus Removal
8 mg/L
1 mg/L
Level 4
BNR, Nitrification/Denitrification and Biological
Phosphorus Removal. High Rate Clarification and
Denitrification Filtration
3 mg/L
0.1 mg/L
Level 5
Nitrification/Denitrification and Biological
Phosphorus Removal. High Rate Clarification
Denitrification Filtration. Micro filtration/Reverse
Osmosis on about Half the Flow
< 2 mg/L
< 0.02 mg/L
Source: WERF, 2011
The following sections present the results of EPA's review based on the total nitrogen rankings
(discussed in Section 5.3.2.1) and the total phosphorus rankings (discussed in Section 5.3.2.2). For the
PSCs prioritized for each of the nutrient discharge rankings, EPA also reviewed the results of the
nutrient impaired waters analysis (see Section 2.5 of the Current Nutrient Report for the methodology of
the nutrient impaired waters analysis and how it was applied).
5.3.2.1 Prioritizing Industries Based on Total Nitrogen Discharge Rankings
From the total nitrogen discharge rankings, 16 PSCs cumulatively make up 95 percent of the total load
in 2018. For most of the PSCs with widespread discharges, at least 75 percent of facilities are reporting
total nitrogen concentrations at or below 2 mg/L. However, some of the PSCs are discharging above 8
mg/L. Therefore, EPA prioritized PSCs with widespread discharges (i.e., not resulting from a few
facilities with high loads), and concentrations above 8 mg/L. This level of nitrogen is commonly
achieved by POTWs with biological nutrient removal (BNR) processes, and by any of EPA case study
facilities (U.S. EPA, 2015). In these PSCs, at least 25 percent of facilities are discharging concentrations
greater than what POTWs with BNR can achieve. See Section 3.1 of the Current Nutrient Report for a
discussion of EPA's review of the total nitrogen discharge rankings for each top PSC.
From this review, EPA is prioritizing the following PSCs for further review: Fertilizer Manufacturing
(40 CFR Part 418) and Explosives Manufacturing (40 CFR Part 457).
5.3.2.2 Prioritizing Industries Based on Total Phosphorus Discharge Rankings
From the total phosphorus discharge rankings, 15 PSCs cumulatively make up 95 percent of the total
load in 2018. EPA first evaluated whether the 2018 total load for each PSC was being driven by a few
facilities, which would not be representative of the industry. If the 2018 total load appeared widespread,
EPA compared the median and third percentile concentrations across the top PSCs. All top PSCs had the
third quartile concentrations above Level 5 for total phosphorus (<0.02 mg/L), indicating that very few
facilities in the top PSCs may be implementing advanced phosphorus removal. Therefore, EPA
prioritized PSCs where the total phosphorus discharges appear widespread among the PSCs facilities
and the 75th percentile concentration value is greater than Level 2 for total phosphorus (1 mg/L).
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From this review, EPA is currently prioritizing the following PSCs for further review: Plastics Molding
and Forming (40 CFR Part 463) and Miscellaneous Foods and Beverages (no current ELGs). See the
Current Nutrients Report (U.S. EPA, 2020b) for more details on this prioritization.
5.4 Industrial Wastewater Treatment Technology Information in the Industrial Wastewater
Treatment Technology Database
EPA continued to collect industrial wastewater treatment performance information to populate the
IWTT Database and made the information available to the public through the IWTT web application.31
EPA identified and screened additional references across a broad range of industries from key technical
conferences on wastewater treatment, including the 2018 Water Environment Federation's Technical
Exhibit and Conference. The IWTT Database currently contains performance data for 58 different
treatment technologies, some of which may be components of a larger treatment system. The IWTT
database contains wastewater treatment technology performance data for 34 industrial PSCs and
removal performance for 195 individual pollutant parameters.
5.5 Industrial Wastewater Treatment Technologies Reviews
EPA received no comment on the industrial wastewater treatment technology review methodology that
it described in Preliminary Plan 14 (see Section 3.6 of Preliminary Plan 14). EPA has the following
goals for the technology reviews.
• Enhance EPA's ability to identify and prioritize industries for further study based on
wastewater treatment technology availability, capabilities, and performance.
• Inform industry studies and rulemakings based on advances/changes in wastewater treatment
technologies.
• Consolidate wastewater treatment technology background information for future reference
and use.
• Collect preliminary information and data on treatment technology costs, where available.
EPA's methodology consists of a three-phase approach to identify and prioritize for further review
technologies that can inform its ELG planning process. The three phases are: (1) technology screening;
(2) preliminary technology review; and (3) technology study.
EPA first focused its technology screening review on nutrient removal in industrial wastewaters. As a
starting point, EPA evaluated the data available in IWTT to identify technologies that have been used to
treat ammonia, nitrogen, and phosphorus, gathering the following details to prioritize technologies for
further review.32
• Number of treatment systems and their scale (full or pilot).
• Average percent removal.
• Number of industries studied.
31 See https://www.epa.gov/eg/indnstrial-wastewater-treatment-techiiologv-database-iwtt.
32 EPA notes that the number of studies in IWTT is a function of how much information EPA has identified through literature
reviews conducted to date and has been entered into the IWTT database and that it is not an exhaustive collection of the
available literature. However, IWTT's structure facilitates this type of information search in a way that is much more readily
available to the Agency than through other research methods available.
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Based on the results of data evaluated in IWTT and the understanding that biological treatment methods
are often used for nutrient removal, and EPA's evaluation of recent research and development trends,
EPA prioritized and developed preliminary treatment technology reviews for suspended growth systems
(activated sludge), membrane bioreactors (MBR), and moving bed biofilm reactors (MBBR) because
these categories cover the main types of biological treatment for which EPA had data. In addition, EPA
also developed a preliminary technology review for membrane systems generally because MBRs include
membranes as the solids separation mechanism and membranes can also be used to remove nutrients
directly in some cases. EPA also considered available information for membrane systems including
microfiltration, ultrafiltration, nanofiltration, and reverse osmosis.
For the four selected technologies, EPA further reviewed data from IWTT and conducted a targeted
literature search to understand the treatment removal mechanisms and identify treatable industrial
wastewater and pollutants targeted for removal. The reviews focused on pilot or full-scale
implementation of the wastewater treatment systems from data sources from 2010 or later to focus on
new applications of these technologies. With these reviews, EPA aims to prioritize at least one
wastewater treatment technology for a detailed technology study that has potential applications across
PSCs.
Table 5-3 summarizes key findings and pollutants removed for each technology identified by EPA from
its review of available data. All four technologies are applicable across a range of industries. See the
Status Update of EPA 's Industrial Wastewater Treatment Technology Reviews memorandum (ERG,
2021) for further discussion and citations.
Table 5-3. Preliminary Technology Review Findings
Tcchnulo£k Description
Targcl
Pollutant*
l-'indings
Activated Sludge
Widely used biological
treatment method using
suspended biomass to
degrade organic pollutants.
Organics
Nutrients
• Much of the current activated sludge research involves
modifying or reconfiguring activated sludge units to provide
nutrient removal.
• Innovations in activated sludge for nutrient removal include:
o Deammonification - Sidestream process to remove
ammonia.
o Nitrition and denitrition - Sidestream technology for
ammonia removal that is effective for treating concentrate
and filtrate recycle streams from dewatering
anaerobically digested biosolids
o OpenCell - Waste activated sludge pretreatment
technology to generate carbon for denitrification
operations.
o Integrated fixed-film activated sludge - Hybrid treatment
that retrofits existing activated sludge environments with
fixed or mobile attached biomass structures to increase
reactor capacity without adding basins.
Moving Bed Biorcactor
Biological treatment
technology using buoyant
free-moving plastic biofilm
carriers in a reactor tank.
The biomass is retained in
the reactor
Organics
Nutrients
• MBBR has advantages over conventional activated sludge:
o Provides higher biomass concentration resulting in
smaller reactor volumes.
o Produces less sludge since the biomass is retained within
the reactor on carriers.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
Table 5-3. Preliminary Technology Review Findings
Tech unlock Description
Tar»e(
Pollutants
l-'indin'^s
o More resistant to load fluctuations.
• MBBR innovations focus on modifying configurations to
optimize treatment for different wastewater characteristics
(e.g., high organic content, high ammonia content).
• MBBRs can be used anywhere conventional activated sludge
may be used. Industrial applications include petroleum
refining, oil and gas extraction, mining, food and beverage
manufacturing, meat and poultry processing, and organic
chemicals manufacturing,
Membrane Biorcactor
Uses a combination of
suspended growth
biological treatment with
membrane filtration for
solids removal.
Organics
Nutrients
• Because membranes are more effective at removing solids,
MBR can produce effluent with lower solids and nutrients
concentrations than conventional activated sludge.
• MBRs can be used as the primary biological component of
an activated sludge wastewater treatment system, as part of a
nutrient removal treatment system, or as a polishing step
following traditional biological treatment
• Membrane costs and cleaning usually make MBR more
expensive than conventional activated sludge. Although
MBR has historically been more expensive than
conventional activated sludge, recent advances in membrane
technology have resulted in cost decreases.
• Recent developments in MBR technology focus on
water/wastewater reuse, fouling control, high strength
wastewater treatment (e.g., food processing), and nutrient
control.
Membranes
Physical barrier that allows
certain substances to pass
through while blocking
others. Pollutants removed
depend on the membrane
pore si/e.
Metals,
suspended and
dissolved
solids, oils and
greases,
viruses,
bacteria.
• Membranes can produce effluent with lower concentrations
than conventional wastewater separation mechanisms such
as gravity settling or multimedia filtration.
• Although membranes have historically been more expensive
than conventional wastewater treatment, recent advances in
membrane technology have resulted in cost decreases.
• Membranes can be used across industries for both
pretreatment of process water and wastewater treatment
across a variety of industries. In wastewater treatment,
membranes may be used to treat the entire waste stream or
for pretreating individual waste streams prior to an end-of-
pipe wastewater treatment system.
• Recent developments in membrane technology focus on
water/wastewater reuse, fouling control, high strength
wastewater treatment (e.g., oil and gas industry, metals
processing), and nutrient control.
Source: ERG, 2021
5.6 Industrial Discharges to Impaired Waters
As described in Preliminary Plan 14, EPA reviewed available information that CWA section 303(d)
requires states to submit biennially to EPA concerning waters that do not meet state water quality
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
standards. The 303(d) database includes information about the location of impaired waterbodies and
categories of probable sources and probable causes of their impairment. At that time, the available data
were not robust enough to be used for ELG planning because few states had relevant data entered into
the system housing that information.
As indicated in Preliminary Plan 14, EPA anticipates future improvements in state data submissions
about impaired waterbodies as implementation of the 303(d) electronic reporting system known as
ATTAINS 2.0 continues. The 303(d) database in the ATTAINS 2.0 framework is expected to yield a
more substantial and usable dataset when states identify an industrial or municipal point source as the
probable cause of an impairment. This improvement over the previous reporting framework could prove
to be useful in future effluent guidelines program planning efforts.
5.7 Review of Industrial Wastewater Discharge Monitoring Report Concentration Data
As part of EPA's 2019 review of ELGs, EPA evaluated concentration data reported by industrial
facilities on DMRs. This analysis, referred to as the cross-category concentration analysis, compares
facility wastewater discharge pollutant concentrations across industrial PSCs to identify categories that
have relatively high pollutant concentration discharges compared to other PSCs and provides a means of
prioritizing specific PSCs for further review and study. Section 5.7.1 provides a discussion of the data
sources, Section 5.7.2 presents the analysis methodology and considerations, Section 5.7.3 provides a
summary of the results, and Section 5.7.4 discusses future potential refinements EPA is considering
making to the analysis. For additional details on the methodology, data quality review, considerations,
and findings from the cross-category concentration analysis, see EPA's Review of Industrial Wastewater
Discharge Monitoring Report (DMR) Data (U.S. EPA, 2020c).
5.7.1 Data Used in the Analysis
For this analysis, EPA evaluated available industrial wastewater discharge data reported on DMRs.
Facilities that directly discharge wastewater to surface waters of the United States pursuant to a NPDES
permit are required to report monitoring data via DMRs for pollutants listed in their NPDES permits.
Facilities send DMRs electronically to their respective NPDES permitting authority (state or EPA). The
DMR data are stored in EPA's centralized program database, ICIS-NPDES. ICIS-NPDES captures
pollutant-specific permit limits, monitoring requirements, and DMR data, including, but not limited to,
facility-, outfall-, and monitoring-period-specific pollutant discharge concentrations, quantities, and
wastewater flows. EPA downloaded DMR data from ICIS-NPDES to rank PSCs by the concentrations
of pollutants in their discharges relative to other PSCs.
EPA downloaded the following three sets of DMR data for calendar year 2017:
• 2017 DMR Industrial Monthly Average Concentration Data (ERG, 2020c)
• 2017 DMR Industrial Monthly Average Quantity Data (ERG, 2020d)
• 2017 DMR Flow Data (ERG, 2020e)
EPA used 2017 data for this review because they were the most recent and complete set of industrial
wastewater discharge data available when this review began.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
5.7.2 Methodology and Considerations for the Analysis
EPA focused the cross-category concentration analysis on toxic and nonconventional pollutants. EPA
excluded conventional pollutants,33 pollutants in drilling fluid, pollutants measured in units that are not
comparable with units for concentration or quantity data (e.g., percent), and whole effluent toxicity
(WET) parameters.
Facilities may monitor and report concentration and quantity data for different statistical bases (i.e.,
averages, maximums, or minimums) and frequencies (e.g., annually, monthly, or daily) depending on
their NPDES permit requirements. To maintain comparability between data reported by facilities and
account for variability of the data throughout the year, EPA used concentration and quantity data
reported as monthly averages in this analysis.
To prepare the data for the analysis, EPA calculated discharged concentrations of pollutants from
reported quantity and flow data (when reported concentration data were not available) and then
combined these calculated monthly average concentration data with reported monthly average
concentration data for all facilities and all monitoring periods into a static database (ERG, 2020f). EPA
then averaged all the monthly average concentrations from 2017 (both reported and calculated) to
calculate a single 2017 average monthly concentration for each pollutant reported for each facility that
could be compared with other facilities for use in the cross-category concentration analysis.
EPA used established crosswalks maintained in the Loading Tool documentation to relate individual
facility and reported pollutants to the most appropriate PSC, commonly based on the facility's primary
reported SIC or North American Industry Classification System (NAICS) code.34
Once the data set was processed, as described above, EPA followed the steps outlined below to compare
wastewater discharge pollutant concentrations across pollutants for facilities in each PSC to identify
categories that have relatively high pollutant concentration discharges compared to other categories. See
EPA's Review of Industrial Wastewater Discharge Monitoring Report (DMR) Data (U.S. EPA, 2020c)
for further details on the methodology.
Step 1: Calculate Median Pollutant Concentrations by PSC
From the concentration dataset, EPA calculated the median of the average monthly
concentrations (hereafter referred to as the median concentration) for each pollutant discharged
by facilities in each PSC. If a pollutant was only reported by one facility within a PSC, EPA
excluded that pollutant from this analysis, because it is unlikely to be representative of
discharges within the PSC.
Step 2: Identify PSCs with Highest Median Concentrations by Pollutant
For each pollutant, EPA sorted the median pollutant concentrations for the PSCs from highest to
lowest and assigned the PSC a rank.
33 CWA section 304(a)(4) designates the following as conventional pollutants: biochemical oxygen demand (BOD5), total
suspended solids, 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).
34 EPA did not review facilities that do not have an industrial classification (did not report a SIC code), facilities that report a
SIC code of 4952 (publicly and privately owned treatment works), and facilities that report a SIC code but are not industrial
facilities.
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
Steps 3: Identify the Number of Top Ranked Pollutants by PSCs and Develop an Overall PSC
Score
For each PSC, EPA counted the number of pollutants where the median concentration for the
PSC was among the five highest median concentrations for the pollutant across all PSCs. To
normalize for the varying number of pollutants reported by each PSC, EPA divided the count of
top-ranking pollutants in the PSC by the total number of pollutants reported by more than one
facility in the PSC. This provided a directly comparable "score" for each PSC representing the
percent of pollutants in the PSC with median concentrations ranked in the top five across PSCs.
Step 4: Rank and Prioritize PSCs for Further Review
EPA ranked each PSC by the PSC score (percent of pollutants with median concentrations
ranked in the top five across PSCs) developed in Step 3 to prioritize categories for further
review.
EPA identified several limitations of the cross-category concentration analysis, which include but are
not limited to:
• Analysis is relative to what other categories are reporting and does not consider the extent of
discharge. A PSC that discharges larger concentrations relative to other categories may or
may not indicate the potential for reducing or eliminating pollutant discharges within that
PSC.
• Analysis uses median concentration and does not directly account for the range of
concentration data within a PSC.
• Analysis does not compare the median pollutant concentrations for a PSC to any national
effluent limitations, if there are any, or to specific permit limits.
• Analysis does not consider the magnitude (i.e., pollutant loading) or toxicity of the pollutants
being discharged.
• Analysis may rank higher those PSCs whose facilities monitor and report pollutants unique
to the PSC simply because few other PSCs report those pollutants.
Even with these limitations, EPA considers the cross-category concentration analysis an appropriate
method to provide a screening-level review of industrial discharges, as it provides an indication of the
extent to which a PSC has larger concentrations of pollutant discharges relative to other PSCs. This
analysis considers all DMR data reported as concentration and quantity simultaneously, including
facilities with only monitoring requirements. To the extent possible, EPA will address the limitations
associated with the analysis as part of the prioritized PSCs review, which will include a review of the
range and magnitude of concentrations.
5.7.3 Results of the Analysis
Table 5-4 presents the results of the cross-category concentration analysis, including the following
information for each PSC:
• PSC score. Percent of pollutants reported by more than one facility where the PSCs median
concentration ranked among the top five highest median concentrations reported for the
pollutant across all PSCs. Value is calculated from the number of pollutants that rank in the
5-14
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
top five and the number of pollutants with data reported. The table is sorted from highest to
lowest PSC Score.
• Number ofpollutants that rank in the top five. Number of pollutants reported by more than
one facility where the PSC's median concentration ranked among the top five highest median
concentrations reported for the pollutant across all PSCs.
• Number of pollutants with data reported. Number of pollutants that were reported by more
than one facility within a PSC and, therefore, considered in the cross-category concentration
analysis for the PSC.
• Total number of pollutants with data. Total number of pollutants with monitoring data within
the PSC in the considered dataset. This includes pollutants that were only reported by one
facility within the PSC. Provides an indication of the number of pollutants that were
excluded from the analysis because they were only reported by a single facility within a PSC
and thus may not be representative of discharges within the category as a whole.
• Total number of facilities. Total number of facilities reporting data within the PSC.
Table 5-4. Results of the Cross-Category Concentration Analysis
40
(IK
Pari
PS( Nil 1110
PSC Score
(Pcrccnl of
Polliiiiinis
lliiil Kiink in
(lie Top l"i\e)
Niiinher of
PolllllillllS
lliiil Kiink in
(lie lop l"i\c
Niiinher of
Polliiiiinis with
Diilii Reported
b\ More lliiin
One l"iicili(\
loliil
Number of
PolllllillllS
willi Diilii
loliil
Niiinher of
l-'iicililics
469
Electrical and electronic
components
100%
2
2
15
5
446
Paint formulating
100%
1
1
13
5
438
Metal products and
machinery
92%
11
12
35
89
417
Soap and detergent
manufacturing
79%
41
52
82
11
454
Gum and wood chemicals
manufacturing
75%
3
4
15
4
414
Organic chemicals, plastics
and synthetic fibers
64%
52
81
223
259
425
Leather tanning and finishing
60%
3
5
20
2
437
Centralized waste treatment
59%
13
22
139
9
455
Pesticide chemicals
57%
4
7
54
57
408
Canned and preserved
seafood processing
56%
5
9
13
25
409
Sugar processing
55%
6
11
33
12
429
Timber products processing
52%
17
33
58
65
461
Battery manufacturing
50%
1
2
6
2
457
Explosives manufacturing
50%
3
6
16
7
435
Oil & gas extraction
49%
21
43
166
78
433
Metal finishing
47%
26
55
110
402
439
Pharmaceutical
manufacturing
47%
14
30
122
27
420
Iron and steel manufacturing
46%
24
52
91
104
419
Petroleum refining
46%
18
39
170
316
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
Table 5-4. Results of the Cross-Category Concentration Analysis
PS( Score
Number of
(Percent of
Number of
Polliiiiinis w ith
Toliil
40
Polliiiiinis
PolllllillllS
Diilii Reported
Number of
loliil
(IR
lliiil Kiink in
lliiil Kiink in
b\ More lliiin
PolllllillllS
Number ol°
Pari
PS( Nil me
(lie Tup l"i\e)
Ihc l op l i\e
One l"iicilil\
willi Diilii
l-'iicililics
415
Inorganic chemicals
manufacturing
45%
19
42
99
97
445
Landfills
44%
16
36
125
154
443
Paving and roofing materials
(tars and asphalt)
44%
7
16
32
38
432
Meat and poultry products
42%
11
26
41
163
450
Construction and
development
42%
13
31
63
45
423
Steam electric power
generating
40%
22
55
189
458
471
Nonferrous metals forming
and metal powders
39%
9
23
58
32
444
Waste combustors
38%
3
8
19
4
418
Fertilizer manufacturing
37%
7
19
33
32
436
Mineral mining and
processing
36%
14
39
70
213
430
Pulp, paper and paperboard
35%
11
31
69
137
421
Nonferrous metals
35%
11
31
62
40
manufacturing
449
Airport deicing
35%
6
17
43
64
442
Transportation equipment
cleaning
35%
8
23
68
39
464
Metal molding and casting
(foundries)
33%
5
15
48
34
406
Grain mills
33%
3
9
17
23
405
Dairy products processing
29%
6
21
33
56
NA
Drinking water treatment
28%
11
39
121
1276
410
Textile mills
27%
4
15
86
42
NA
Food service establishments
25%
2
8
15
117
468
Copper forming
25%
1
4
15
6
NA
Independent and standalone
labs
22%
2
9
80
18
422
Phosphate manufacturing
22%
2
9
14
15
NA
Unassigned waste facility
22%
9
41
115
134
NA
Miscellaneous foods and
beverages
22%
5
23
40
70
434
Coal mining
21%
7
33
47
1713
412
Concentrated animal feeding
operation (CAFO)
20%
1
5
10
18
424
Ferroalloy manufacturing
19%
3
16
40
8
407
Canned and preserved fruits
and vegetables processing
19%
3
16
26
47
426
Glass manufacturing
18%
4
22
57
25
460
Hospital
18%
3
17
24
145
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5—Reviews of Industrial Wastewater Discharges and Treatment Technologies
Table 5-4. Results of the Cross-Category Concentration Analysis
PS( Score
Number of
(Percent of
Number of
Polliiiiinis w ith
Toliil
40
Polliiiiinis
PolllllillllS
Diilii Reported
Number ol°
Tol;il
(IR
lliiil Kiink in
lliiil Kiink in
b\ More lliiin
PolllllillllS
Number ol°
Pari
PS( Niimc
(lie Tup l"i\e)
Ihc l op l i\e
One l"iicilil\
willi Diilii
l-'iicililics
411
Cement manufacturing
17%
4
23
42
48
451
Concentrated aquatic animal
production
13%
2
15
27
179
467
Aluminum forming
13%
1
8
24
9
440
Ore mining and dressing
10%
3
29
50
82
428
Rubber manufacturing
6%
1
18
94
46
463
Plastics molding and forming
0%
0
10
28
34
NA
Printing & publishing
-
0
0
7
2
NA
Industrial laundries
-
0
0
2
2
NA
Tobacco products
-
0
0
2
1
465
Coil coating
-
0
0
1
1
458
Carbon black manufacturing
-
0
0
4
2
447
Ink formulating
-
0
0
1
1
Source: ERG, 2020f
NA: Not Applicable
5.7.4 Potential A nalysis Refinements
EPA envisions the cross-category concentration analysis to be a dynamic screening level analysis that
can be adapted in future annual reviews and ELG planning cycles to further refine EPA's prioritization
of PSCs for review. As such, EPA has identified the following steps and plans to take them in future
reviews to expand the scope of the current analysis.
• Update DMR data. Industrial facilities submit new DMRs continuously, based on permit and
reporting requirements. EPA may refresh the cross-category concentration analysis with
updated DMR data to review the current state of discharges within and across PSCs. This
will capture changes based on updated permitting requirements and the incorporation of
emerging pollutants that are added to permits to address water quality criteria and standards.
• Evaluate pollutant loads. The current cross-category concentration analysis uses
concentration data submitted through DMRs. EPA may perform the cross-category analysis
using pollutant loads (pounds of pollutants discharged per year) instead of, or in addition to,
concentrations to capture the magnitude of the discharge and account for the impact of
facility and industry flow.
• Include TRIdata. If conducting a pollutant loads analysis, EPA may also consider
incorporating TRI data, to assess discharges of additional toxic pollutants not reported on
DMRs, as well as indirect discharges. The TRI program only requires reporting of pollutant
loads; it does not provide data on pollutant concentrations or facility flows.
• Focus analysis on specific group(s) of pollutants. EPA may perform the cross-category
concentration analysis for a specific group of pollutants (e.g., metals, organics, toxics),
depending on Agency priorities or the availability of a viable technology to treat specific
pollutants or pollutant groups.
5-17
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6—Ongoing ELG Studies
6. Ongoing ELG Studies
This section summarizes the status of EPA's ongoing ELG studies.
6.1 Detailed Study of the Petroleum Refining Category (40 CFR Part 419)
EPA is concluding its detailed study of wastewater discharges from the petroleum refining industry (40
CFR 419) and is not taking further action on this source category at this time. EPA initiated this study to
investigate concerns about increased discharges of metals from petroleum refineries due to
implementation of wet air-pollution controls and changes in crude oil feedstock. As part of the study,
EPA also investigated discharges of dioxin and dioxin-like compounds from petroleum refineries to
discern whether these pollutants were being discharged at detectible concentrations. EPA conducted
extensive data collection activities as part of this study, including visiting 10 refineries, collecting
detailed questionnaire responses from 21 refineries, reviewing 80 NPDES permits, and attending annual
meetings with representatives from the refining industry and petroleum refining trade associations since
2014.
The data EPA gathered on the impact of wet air-pollution controls and changes in crude oil feedstock
during the detailed study was inconclusive. The data did not demonstrate whether implementation of wet
air-pollution controls or changes in crude oil feedstocks have had an impact on the characteristics of the
wastewater generated by the industry. The Agency found some limited published information about the
potential presence of naphthenic acids and alkylated polynuclear aromatic hydrocarbons (alkylated
PAHs) in wastewaters from processing heavier crudes; however, there was no actual data on discharges
of these pollutants for EPA to evaluate.
The information EPA gathered on discharges of dioxin and dioxin-like compound from petroleum
refineries indicated that dioxin discharges found during an initial review of the petroleum refining
industry were primarily due to discharges from a single refinery that was in upset at the time they
reported their effluent data. Additional details about the study, information EPA collected as part of the
study, and limitations on available data are provided in the Final 2019 Petroleum Refining Detailed
Study Report (U.S. EPA, 2019c).
EPA discussed its proposed decision to conclude this study in Preliminary Plan 14 and did not receive
any comments that warrant EPA changing its proposed decision. More detailed responses to the
comments EPA received on its proposed decision are included in the Comment Response Document for
Preliminary Plan 14 (U.S. EPA, 2020a).
Though EPA is concluding this particular study of the petroleum refining industry, EPA will continue to
review the petroleum refining category, consistent with the CWA. EPA will continue to collaborate with
the industry and other stakeholders regarding future data assessments and methodologies.
6.2 Detailed Study of Electrical and Electronic Components Category (40 CFR Part 469)
As the result of the 2015 Annual Review (U.S. EPA, 2016), EPA decided to conduct a detailed study of
the E&EC PSC (40 CFR Part 469). The E&EC ELGs were issued in 1983 and have not been revised.
EPA intends to study if considerable changes and innovations achieved by this industry warrant
considering revisions to the existing ELGs.
As part of the detailed study of the E&EC industry, EPA is working to identify the population of
facilities subject to the regulation to study further. EPA has been in contact with industry trade groups
6-1
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6—Ongoing ELG Studies
likely to be associated with regulated facilities and has started building a profile of the regulated
community. EPA has searched permitting databases for facilities that have a discharge permit that
contains conditions from the E&EC ELGs. This type of search will only yield partial lists as most E&EC
facilities discharge their wastewater to a POTW and will not be present in those databases. EPA has also
been contacting permitting authorities to build a database of those facilities that discharge to a POTW.
To date, EPA has acquired information on over 100 facilities permitted as an E&EC facility discharging
to POTWs. EPA has also acquired permits and monitoring reports from many of these facilities which
discuss treatment technologies being used and the concentration of contaminants in their waste stream.
At this time, EPA has conducted five site visits, all of which yielded valuable information regarding
manufacturing techniques, chemicals used, and changes to the industry since the rule was issued.
6.3 Study of Oil and Gas Extraction Wastewater Management
In May of 2018, EPA initiated a study of the management of produced water from the onshore oil and
gas extraction industry. During the study EPA held more than 80 meetings and conference calls with
states, tribes and stakeholders and held a public meeting in October 2018 to provide an overview of the
input received from these various groups. On May 15, 2019, EPA released a draft study report for public
input. The draft study report describes the outreach activities and what EPA learned during the study
period. After considering public input received on the draft report, EPA published a final report in May
of 2020. The Agency is still determining what, if any, next steps should be taken regarding produced
water management under the CWA. See. and Gas Management webpaee35 for more
information.
In the 2020 Fall Regulatory Agenda, EPA announced it is initiating rulemaking to revise definitions in
the Centralized Waste Treaters Effluent Guideline (40 CFR Part 437) to increase flexibility for
centralized waste treaters who treat and discharge produced water from oil and gas extraction (40 CFR
Part 437). EPA plans to propose revising sections 40 CFR Part 437 to expand the beneficial use of
treated produced waters by allowing, under certain circumstances, the discharge of produced waters
from Centralized Waste Treatment facilities and from POTWs. These revisions would allow more
flexibility in the discharge, and ultimately the management of treated produced waters for agricultural
uses, reuse for oil recovery, and other uses to alleviate water scarcity.
6.4 Study of Per- and Polyfluoroalkyl Industrial Sources and Discharges
As described in the October 2019 Preliminary Plan 14, EPA is conducting a Multi-industry Detailed
Study of industrial PFAS use, treatment and discharges to surface water and POTWs focusing on four
PSCs: PFAS manufacturers, pulp and paper manufacturers, textile and carpet manufacturers, and
airports. After publication of the Preliminary Plan 14, an additional PSC, Metal Finishers, was added to
the Study. The addition of this new category was based on information and data received by EPA from
the metal finishers industry and a review of PFAS source inventories conducted by states (ERG, 2019a,
2019b, 2019c, 2020g, 2020h). As part of the detailed study, EPA is collecting facility-specific
information such as the types of PFAS compounds discharged, discharge concentrations, treatment
methods, and facility flow rates. This information has primarily been collected through outreach to
stakeholders, including company representatives, trade associations, state, regional, and local
wastewater regulatory authorities, treatment technology vendors, and non-governmental organizations.
EPA is evaluating this information to inform decisions about how best to address industrial PFAS
35 See EPA's Oil and Gas Management webpage for more information: https://www.epa. gov/eg/studv-oi 1-and-gas-extraction~
wastewater-inanagement
6-2
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6—Ongoing ELG Studies
discharges. The Agency is continuing to collect information and intends to provide for public review and
comment the information and data regarding PFAS manufacturers and formulators that EPA has
collected to date. EPA will request public comment on this information and data and solicit additional
information and data regarding discharges of PFAS from these facilities to inform potential future
revisions to the wastewater discharge requirements that apply to the OCPSF PSC. EPA intends to
publish an advanced notice of proposed rulemaking (ANPRM) to solicit data and information regarding
manufacturers of PFAS and the presence and treatment of PFAS in discharges from this industrial
category. EPA also intends to request information regarding PFAS formulators, which are facilities that
produce a variety of PFAS products and materials from PFAS feedstocks. EPA will provide data and
information on the other PSCs once data collection and analysis is completed.
While EPA takes additional steps regarding PFAS manufacturers and formulators, EPA will continue its
Multi-industry Detailed Study described above to collect additional information about PFAS discharges
from the four remaining PSCs included in the study. While there has been significant study in recent
years on the presence of PFAS in the environment, and the presence of PFAS in drinking water in
particular, there has been relatively little study of the discharges of PFAS into water. As a result, there is
limited information about PFAS discharges, including the types of PFAS compounds discharged,
concentrations of PFAS discharged, and the significant sources of PFAS discharges. EPA has collected
more of this type of information for PFAS manufacturers and formulators than it has for the other four
categories included in the study but expects that the detailed study will help fill some of these data gaps
and help EPA identify appropriate future actions to address PFAS discharges for the four remaining
categories included in the study. Further study of the remaining four categories is needed before
initiating rulemaking to address PFAS discharges from these categories.
Embarking on an effluent guidelines rulemaking is a significant deployment of limited Agency time and
resources, generally entailing many years and significant resources. Before EPA embarks on such an
endeavor, EPA would want some idea that there are promising candidate technologies that might reflect
BAT. More specifically, developing effluent guidelines requires EPA to gather information on industry
practices, characteristics of discharges (e.g., pollutants, flow variability, stormwater), technologies or
practices used to prevent or treat the discharge, and economic characteristics. EPA identifies the best
available technology that is economically achievable for that industry and sets regulatory requirements
based on the performance of that technology. Before EPA were to initiate such a significant undertaking,
EPA would want to have this type of information. Given the data EPA currently has, taking the
additional steps described above regarding PFAS manufacturers and formulators and continuing the
detailed study on the four other PSCs included in the study is warranted.
6.5 Study of Meat and Poultry Products Point Source Category (40 CFR Part 432)
As a result of the cross-industry review of nutrients in industrial wastewater and the results of the Meat
and Poultry Products preliminary category review, EPA initiated a detailed study of wastewater
discharges from the Meat and Poultry Products PSC (40 CFR Part 432). In February 2020, EPA met
with trade associations and provided an overview of the data available and the data needed to determine
if a rule revision might be appropriate.
EPA is in the process of building an industry profile of Meat and Poultry Products facilities based on
publicly available sources. To develop a list of facilities potentially included in this PSC, EPA evaluated
Meat and Poultry Products industry directories from the U.S. Department of Agriculture (USDA) Food
Safety Inspection Service (FSIS), the U.S. Food and Drug Administration (FDA), and the National
Renderers Association. To further develop this list, EPA is also evaluating information from POTW
6-3
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6—Ongoing ELG Studies
Annual Reports, EPA's ICIS-NPDES database, and EPA's TRI database. Based on EPA's preliminary
review, the Meat and Poultry Products industry includes roughly 7,000 facilities of which about 1,200
have NPDES permits, for storm water discharges or process wastewater discharges. Approximately 500
facilities have DMR data in ICIS-NPDES. EPA is currently reviewing the contents of these permits and
associated DMRs to better understand the industry. EPA's review is currently limited to facilities with
effluent limits (based on ELGs, WQBELs or TMDLs) and NPDES permits, which tend to include only
large, direct discharge facilities. EPA does not have as much information on smaller direct discharge
facilities and indirect discharge facilities because those facilities do not submit information about
nitrogen discharges in EPA's ICIS NPDES database. EPA is working to collect this information through
other means to inform its evaluation of this PSC.
EPA is also evaluating data to determine which wastewater treatment technologies are currently in use
and the effectiveness of nutrient removal. Specifically, EPA is reviewing NPDES permits, POTW
annual reports, and available indirect discharge inspection reports from significant industrial users. EPA
is also reviewing information to identify candidates for site visits to learn more about the industry
operations and wastewater treatment. Furthermore, EPA is evaluating available data to identify other
treatment technologies that may be available to the industry (but not necessarily currently in use by the
Meat and Poultry Products facilities) to treat their wastewater beyond the existing ELG requirements.
Additionally, to better document the impacts of the Meat and Poultry Products industry on the
environment, EPA is conducting literature searches for any documented environmental or human health
impacts associated with Meat and Poultry Products facilities. EPA is studying the proximity of Meat and
Poultry Products wastewater discharges to impaired waters. Since nutrients are the primary concern,
EPA is estimating the nutrient loadings associated with Meat and Poultry Products wastewater
discharges and developing watershed and water quality eutrophication models. Modeling locations will
be determined by factors that include the availability of data and the magnitude of discharge loadings.
Widely used and peer reviewed water quality models will be used. These models would be used to
evaluate environmental improvement due to pollutant loading removals resulting from potential Meat
and Poultry Products wastewater treatment improvements.
Developing effluent guidelines is a resource intensive endeavor that requires EPA to gather information
on industry practices, characteristics of discharges (e.g., pollutants, flow variability, stormwater),
technologies or practices used to prevent or treat the discharge, and economic characteristics. EPA
identifies the appropriate level of technology as prescribed by the CWA and sets effluent limitations
based on the performance of that technology. Given the data gaps, EPA has identified in the Meat and
Poultry Products category, conducting a detailed study is needed to gather more information prior to
deciding if a revision to the ELG is appropriate. As such, EPA is announcing that the Agency will
conduct a detailed study of the Meat and Poultry Products category.
EPA typically performs ELG revisions on both direct and indirect dischargers concurrently, as the
economic impacts to the industry are not cleanly severable between those classes of dischargers. EPA
considers a detailed study the best way to account for the complexity of the industry, address the data
gaps described above, and inform a decision as to whether or not engaging in a rulemaking is
appropriate. This study will facilitate a more complete understanding the total number of facilities, the
locations of the facilities across the US, the size of the facilities, and the characteristics of the processes
and wastewater generated.
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7—Ongoing ELG Rulemaking
1. Ongoing ELG Rulemaking
This section summarizes the status of EPA's ongoing ELG rulemaking efforts.
7.1 Steam Electric Power Generating Point Source Category (40 CFR Part 423)
EPA promulgated new ELG's for the Steam Electric Power Generating PSC in 2015. That rule was
subject to legal challenge and in addition the agency received two petitions for administrative
reconsideration. In response to the two administrative petitions, EPA agreed to reconsider the Effluent
Guidelines for two waste streams: flue gas desulfurization (FGD) wastewater and bottom ash (BA)
transport water. The legal challenges to the 2015 ELGs for these two waste streams were held in
abeyance while EPA reconsidered the ELG's.
EPA completed its reconsideration of the ELG's for FGD wastewater and BA transport water in August
2020, establishing effluent limits for FGD wastewater and for BA transport water to better protect public
health and the environment by limiting wastewater discharges into surface waters and wastewater
treatment plants, while also reducing costs. See the Effluent Guidelines website36 for further details.
EPA conducted a webinar on November 5, 2020 to inform the public, industry, and state and local
officials about the contents of the new rule.
Meanwhile, on April 12, 2019, the U.S. Court of Appeals for the Fifth Circuit rendered a decision on the
legal challenges to portions of the 2015 rule that had not been held in abeyance.
The Fifth Circuit struck down as unlawful aspects of the 2015 ELG's pertaining to effluent limitations
for "legacy" wastewater and combustion residual leachate. These provisions had been challenged by
environmental group petitioners. The Fifth Circuit held that EPA's legacy wastewater limitations were
arbitrary and capricious under the Administrative Procedure Act (APA) and that EPA's leachate
limitations were unlawful under the CWA, pursuant to the familiar Chevron test for reviewing an
agency's interpretation of a statute that it administers. The Court vacated those portions of the 2015
ELG rule and remanded them to the Agency "for reconsideration consistent with this opinion." In the
2020 Fall Regulatory Agenda, EPA announced its plan to initiate a rulemaking to revise the Steam
Electric ELG's to establish Best Available Technology Economically Achievable limitations for these
two waste streams (landfill leachate and legacy wastewater) that were vacated by the Fifth Circuit in its
April 2019 decision. The schedule for this rulemaking has yet to be determined.
36 See the following website for further details: https://www.epa.gov/eg/2020~steam-electric~reconsideration-nile~doeiiments
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8—Summary Table of Plans for Existing Point Source Categories
8. Summary Table of Plans for Existing Point Source Categories
Table 8-1 summarizes the plans for future activity based on EPA's review of the effluent guidelines and
pretreatment standards of the existing PSCs. As explained in Section 2.3, above, EPA does not interpret
the CWA as requiring it to decide every year whether to revise the effluent guidelines and pretreatment
standards. The table below summarizes the status of EPA's ongoing review process. EPA uses the
following codes to describe its findings and potential next steps for each industrial category.
A. EPA recently promulgated or revised effluent guidelines or pretreatment standards for this
category.
B. EPA is undergoing rulemaking for this category.
C. No further action is appropriate for the effluent guidelines and pretreatment standards for
this category at this time.
D. EPA intends to continue the review or study of this category.
E. EPA intends to initiate a review or study of this category.
F. EPA plans to or is in the process of issuing an ANPRM for this category.
Table 8-1. Summary of Plans from EPA's Review of Existing Industrial Categories
N«i.
liulusln ( ;ik'iior\ Misled ;ilph;ihcMic;ill> )
40 ( I K Part
l-'inriin^ls)
1
Airport De icing
449
C
2
Aluminum Forming
467
C
3
Asbestos Manufacturing
427
c
4
Battery Manufacturing
461
c
5
Canned and Preserved Fruits and Vegetable Processing
407
c
6
Canned and Preserved Seafood Processing
408
c
7
Carbon Black Manufacturing
458
c
8
Cement Manufacturing
411
c
9
Centralized Waste Treatment
437
B
10
Coal Mining
434
C
11
Coil Coating
465
C
12
Concentrated Animal Feeding Operations (CAFO)
412
C
13
Concentrated Aquatic Animal Production
451
c
14
Construction and Development
450
c
15
Copper Forming
468
c
16
Dairy Products Processing
405
c
17
Dental Offices
441
A
18
Electrical and Electronic Components
469
D
19
Electroplating
413
C
20
Explosives Manufacturing
457
E
21
Ferroalloy Manufacturing
424
C
22
Fertilizer Manufacturing
418
E
23
Glass Manufacturing
426
C
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8—Summary Table of Plans for Existing Point Source Categories
Table 8-1. Summary of Plans from EPA's Review of Existing Industrial Categories
No.
liulusln ( ;ik'iior\ (listed ;ilph;ihelic;ill> )
40 ( I K Piirl
l-'inriiiii^s)
24
Grain Mills
406
C
25
Gum and Wood Chemicals
454
C
26
Hospitals
460
c
27
Ink Formulating
447
c
28
Inorganic Chemicals
415
c
29
Iron and Steel Manufacturing
420
c
30
Landfills
445
c
31
Leather Tanning and Finishing
425
c
32
Meat and Poultry Products
432
D
33
Metal Finishing
433
E
34
Metal Molding and Casting
464
C
35
Metal Products and Machinery
438
C
36
Mineral Mining and Processing
436
c
37
Nonferrous Metals Forming and Metal Powders
471
c
38
Nonferrous Metals Manufacturing
421
c
39
Oil and Gas Extraction
435
B
40
Ore Mining and Dressing
440
C
41
Organic Chemicals. Plastics, and Synthetic Fibers
414
F
42
Paint Formulating
446
C
43
Paving and Roofing Materials (Tars and Asphalt)
443
C
44
Pesticide Chemicals
455
c
45
Petroleum Refining
419
c
46
Pliarinaceutical Manufacturing
439
c
47
Phosphate Manufacturing
422
c
48
Photographic
459
c
49
Plastics Molding and Forming
463
E
50
Porcelain Enameling
466
c
51
Pulp, Paper and Paperboard
430
D
52
Rubber Manufacturing
428
C
53
Soap and Detergent Manufacturing
417
C
54
Steam Electric Power Generating
423
B
55
Sugar Processing
409
C
56
Textile Mills
410
D
57
Timber Products Processing
429
C
58
Transportation Equipment Cleaning
442
C
59
Waste Combustors
444
C
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9—References for Plan 14
9. References for Plan 14
1. ERG. 2019a. Eastern Research Group, Inc. Notes from Meeting with the City of Grand
Rapids, Michigan Water Resource Recovery Facility. (October). EPA-HQ-OW-2018-0618.
DCN 08769.
2. ERG. 2019b. Eastern Research Group, Inc. Notes from Meeting with Great Lakes Water
Authority (GLWA). (October). EPA-HQ-OW-2018-0618. DCN 08786.
3. ERG. 2019c. Eastern Research Group, Inc. EPA 's PFAS Multi-Industry Study: Notes from
Meeting with Michigan Department of Environment, Great Lakes, and Energy.
(November). EPA-HQ-OW-2018-0618. DCN 08787.
4. ERG. 2020a. Eastern Research Group, Inc. 2018 DMR Data - Total Nitrogen. EPA-HQ-
OW-2018-0618. DCN 08776.
5. ERG. 2020b. Eastern Research Group, Inc. 2018 DMR Data - Total Phosphorus. EPA-HQ-
OW-2018-0618. DCN 08777.
6. ERG. 2020c. Eastern Research Group, Inc. 2017 DMR Industrial Monthly Average
Concentration Data. EPA-HQ-OW-2018-0618. DCN 08766.
7. ERG. 2020d. Eastern Research Group, Inc. 2017 DMR Industrial Monthly Average
Quantity Data. EPA-HQ-OW-2018-0618. DCN 08767.
8. ERG. 2020e. Eastern Research Group, Inc. 2017 DMR Flow Data. EPA-HQ-OW-2018-
0618. DCN 08768.
9. ERG. 2020f. Eastern Research Group, Inc. Index of Tables and Queries for 2017 DMR
Data Processing. EPA-HQ-OW-2018-0618. DCN 08770.
10. ERG. 2020g. Eastern Research Group, Inc. EPA's PFAS Detailed Study: Notes from
Meeting with Wisconsin Department of Natural Resources. (January). EPA-HQ-OW-2018-
0618. DCN 08788.
11. ERG. 2020h. Eastern Research Group, Inc. Notes from Meeting with National Association
of Surface Finishing. (February). EPA-HQ-OW-2018-0618. DCN 08789.
12. ERG. 2021. Eastern Research Group, Inc. Status Update of EPA's Industrial Wastewater
Treatment Technology Reviews. (January). EPA-HQ-OW-2018-0618. DCN 08792.
13. Jeyanayagam, Sam. 2005. True Confessions of the Biological Nutrient Removal Process.
Florida Water Resources Journal: January 2005. EPA-HQ-OW-2018-0618. DCN 08791.
14. U.S. EPA. 2012. Technical Users Background Document for the Discharge Monitoring
Report (DMR) Pollutant Loading Tool. (January). Available online at:
https://echo.epa.gov/trends/loading-tool/water-pollution-
Search/results/?s=546008a2bc3d6f6e2fd0ce45cb789d7d35c77c40. EPA-HW-OW-2014-
0170-0058.
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9—References for Plan 14
15. U.S. EPA. 2015. Case Studies on Implementing Low-Cost Modifications to Improve
Nutrient Reduction at Wastewater Treatment Plants. Washington, D.C. (August). EPA-HQ-
OW-2018-0618. DCN 08790.
16. U.S. EPA. 2016. The 2015 Annual Effluent Guidelines Review Report. Washington, D.C.
(June). EPA-821-R-16-002. EPA-HQ-OW-2015-0665-0299.
17. U.S. EPA. 2019a. The EPA 's Review of Nutrients in Industrial Wastewater Discharge.
Washington, D.C. (October). EPA-HQ-OW-2018-0618-0569.
18. U.S. EPA. 2019b. Preliminary Effluent Guidelines Program Plan 14. Washington, D.C.
(October). EPA-821-R-19-005. EPA-HQ-OW-2018-0618-0572.
19. U.S. EPA. 2019c. Final 2019 Petroleum Refining Detailed Study Report. Washington, D.C.
(September). EPA-HQ-OW-2018-0618-0349.
20. U.S. EPA. 2020a. Comment Response Document for Preliminary Plan 14. Washington,
D.C. (December). EPA-HQ-OW-2018-0618. DCN 08781.
21. U.S. EPA. 2020b. EPA 's Review of Nutrients in Industrial Wastewater Discharge.
Washington, D.C. (December). EPA-HQ-OW-2018-0618. DCN 08784.
22. U.S. EPA. 2020c. Eastern Research Group, Inc. EPA's Review of Industrial Wastewater
Discharge Monitoring Report (DMR) Data. (December). EPA-HQ-OW-2018-0618. DCN
08785.
23. WERF. 2011. Water Environment Research Foundation. Striking the Balance Between
Nutrient Removal in Wastewater Treatment and Sustainability. (October 14). EPA-HQ-
OW-2018-0618-0509.
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