Document ID: EPA-HQ-OW-2018-0056-0001
Agency: epa
Document Type: Proposed Rule
Title: Water Quality Standards; Establishment of a Numeric Criterion for Selenium for the State of California
Posted Date: 2018-12-13T05:00Z

[Federal Register Volume 83, Number 239 (Thursday, December 13, 2018)]
[Proposed Rules]
[Pages 64059-64078]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-26781]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 131

[EPA-HQ-OW-2018-0056; FRL-9987-61-OW]
RIN 2040-AF79

Water Quality Standards; Establishment of a Numeric Criterion for 
Selenium for the State of California

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
establish a federal Clean Water Act (CWA) selenium water quality 
criterion applicable to California that protects aquatic life and 
aquatic-dependent wildlife in the fresh waters of California. In 2016, 
the EPA published a revised recommended aquatic life selenium criterion 
for freshwater based on the latest scientific knowledge. The EPA is 
proposing to amend the California Toxics Rule to include a revised 
statewide chronic selenium water quality criterion for California fresh 
waters to protect aquatic life and aquatic-dependent wildlife which 
builds upon the science in the EPA's 2016 Final Aquatic Life Ambient 
Water Quality Criteria for Selenium--Freshwater.

DATES: Comments date: Comments must be received on or before February 
11, 2019.
    Public hearing dates: Tuesday, January 29, 2019 from 9 a.m.-11 a.m. 
PT, Wednesday, January 30, 2019 from 4 p.m.-6 p.m. PT.

ADDRESSES: Comments: Submit your comments, identified by Docket ID No. 
EPA-HQ-OW-2018-0056, at https://www.regulations.gov (our preferred 
method), or the other methods identified at https://www.epa.gov/dockets/commenting-epa-dockets. Once submitted, comments cannot be 
edited or removed from the docket. The EPA may publish any comment 
received to its public docket. Do not submit electronically any 
information you consider to be Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. 
Multimedia submissions (audio, video, etc.) must be accompanied by a 
written comment. The written comment is considered the official comment 
and should include discussion of all points you wish to make. The EPA 
will generally not consider comments or comment contents located 
outside of the primary submission (i.e., on the web, cloud, or other 
file sharing system). For additional submission methods, the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either electronically 
in www.regulations.gov or in hard copy at two Docket Facilities. The 
Office of Water (``OW'') Docket Center is open from 8:30 a.m. until 
4:30 p.m., Monday through Friday, excluding legal holidays. The Docket 
telephone number is (202) 566-2426 and the Docket address is OW Docket, 
EPA West, Room 3334, 1301 Constitution Ave. NW, Washington, DC 20004. 
The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday 
through Friday, excluding legal holidays. The telephone number for the 
Public Reading Room is (202) 566-1744.
    Public Hearings: The EPA is offering two online public hearings so 
that interested parties may provide oral comments on this proposed 
rulemaking. For more details on the public hearings and a link to 
register, please visit https://www.epa.gov/wqs-tech/water-quality-standards-establishment-numeric-criterion-selenium-fresh-waters-california.

FOR FURTHER INFORMATION CONTACT: Julianne McLaughlin, Office of Water, 
Standards and Health Protection Division (4305T), U.S. Environmental 
Protection Agency, 1200 Pennsylvania Avenue NW, Washington, DC 20460; 
telephone number: (202) 566-2542; email address: 
mclaughlin.julianne@epa.gov; or Diane E. Fleck, P.E., Esq., Water 
Division (WTR-2-1), U.S. Environmental Protection Agency Region 9, 75 
Hawthorne Street, San Francisco, CA 94105; telephone number: (415) 972-
3527; email address: Fleck.Diane@EPA.gov.

SUPPLEMENTARY INFORMATION: This proposed rule is organized as follows:

I. General Information
II. Background
    A. Statutory and Regulatory Authority
    B. National Toxics Rule
    C. California Toxics Rule
    D. Litigation
    E. Selenium and Sources of Selenium
III. Proposed Criterion
    A. Approach
    B. Administrator's Determination of Necessity
    C. Proposed Criterion
    D. Implementation
    E. Incorporation by Reference
IV. Endangered Species Act
V. Applicability of the EPA Promulgated Water Quality Standards When 
Final
VI. Implementation and Alternative Regulatory Approaches
II. Economic Analysis
    A. Identifying Affected Entities
    B. Method for Estimating Costs
    C. Results
VIII. Statutory and Executive Orders
    A. Executive Order 12866 (Regulatory Planning and Review) and 
Executive

[[Page 64060]]

Order 13563 (Improving Regulation and Regulatory Review)
    B. Executive Order 13771 (Reducing Regulations and Controlling 
Regulatory Costs)
    C. Paperwork Reduction Act (PRA)
    D. Regulatory Flexibility Act (RFA)
    E. Unfunded Mandates Reform Act (UMRA)
    F. Executive Order 13132 (Federalism)
    G. Executive Order 13175 (Consultation and Coordination With 
Indian Tribal Governments)
    H. Executive Order 13045 (Protection of Children from 
Environmental Health and Safety Risks)
    I. Executive Oder 13211 (Actions That Significantly Affect 
Energy Supply, Distribution, or Use)
    J. National Technology Transfer and Advancement Act of 1995
    K. Executive Order 12898 (Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations)

I. General Information

Applicability

    Entities such as industries, stormwater management districts, or 
publicly owned treatment works (POTWs) that directly or indirectly 
discharge selenium to the fresh waters of California could be 
indirectly affected by this rulemaking because federal water quality 
standards (WQS) promulgated by the EPA would apply to CWA regulatory 
programs, such as National Pollutant Discharge Elimination System 
(NPDES) permitting. Citizens concerned with water quality in California 
could also be interested in this rulemaking. Categories and entities 
that could be affected include the following:

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                                      Examples of potentially-affected
             Category                             entities
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Industry..........................  Industries discharging pollutants to
                                     fresh waters of California.
Municipalities....................  Publicly owned treatment works or
                                     other facilities discharging
                                     pollutants to fresh waters of
                                     California.
Stormwater Management Districts...  Entities responsible for managing
                                     stormwater discharges to fresh
                                     waters of California.
Agriculture.......................  Entities with agriculture drainage
                                     to fresh waters of California.
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    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities that could be affected by this 
action. Any parties or entities who depend upon or contribute to the 
water quality of California waters where the freshwater criterion would 
apply could be indirectly affected by this proposed rule. To determine 
whether your facility or activities could be affected by this action, 
you should carefully examine this proposed rule. If you have questions 
regarding the applicability of this action to a particular entity, 
consult the person listed in the FOR FURTHER INFORMATION CONTACT 
section.

II. Background

A. Statutory and Regulatory Authority

    CWA section 101(a)(2) (33 U.S.C. 1251(a)(2)) establishes a national 
goal, wherever attainable, of ``water quality which provides for the 
protection and propagation of fish, shellfish, and wildlife and 
provides for recreation in and on the water . . .'' In this proposal, 
the relevant goals are the protection and propagation of fish, 
shellfish, and wildlife.
    CWA section 303(c) (33 U.S.C. 1313(c)) directs states to adopt WQS 
for their waters subject to the CWA. CWA section 303(c)(2)(A) \1\ 
requires that whenever a state revises or adopts a new standard that 
the state's WQS specify designated uses of the waters and water quality 
criteria based on those uses. The EPA's regulations at 40 CFR 
131.11(a)(1) provide that ``[s]uch criteria must be based on sound 
scientific rationale and must contain sufficient parameters or 
constituents to protect the designated use [and] [f]or waters with 
multiple use designations, the criteria shall support the most 
sensitive use.'' In addition, 40 CFR 131.10(b) provides that ``[i]n 
designating uses of a water body and the appropriate criteria for those 
uses, the [s]tate shall take into consideration the water quality 
standards of downstream waters and shall ensure that its water quality 
standards provide for the attainment and maintenance of the water 
quality standards of downstream waters.''
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    \1\ CWA 303(c)(2)(A): Whenever the State revises or adopts a new 
standard, such revised or new standard shall be submitted to the 
Administrator. Such revised or new water quality standard shall 
consist of the designated uses of the navigable waters involved and 
the water quality criteria for such waters based upon such uses. 
Such standards shall be such as to protect the public health or 
welfare, enhance the quality of water and serve the purposes of this 
chapter. Such standards shall be established taking into 
consideration their use and value for public water supplies, 
propagation of fish and wildlife, recreational purposes, and 
agricultural, industrial, and other purposes, and also taking into 
consideration their use and value for navigation.
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    States are required to review applicable WQS at least once every 
three years and, if appropriate, revise or adopt new WQS (CWA section 
303(c)(1) \2\ and 40 CFR 131.20). Any new or revised WQS must be 
submitted to the EPA for review and approval or disapproval (CWA 
section 303(c)(2)(A) and (c)(3) \3\ and 40 CFR 131.20 and 131.21). 
Under CWA section 303(c)(4)(B),\4\ the Administrator is authorized to 
determine that a new or revised standard is needed to meet CWA 
requirements.
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    \2\ CWA 303(c)(1): The Governor of a State or the state water 
pollution control agency of such State shall from time to time (but 
at least once each three year period beginning with October 18, 
1972) hold public hearings for the purpose of reviewing applicable 
water quality standards and, as appropriate, modifying and adopting 
standards. Results of such review shall be made available to the 
Administrator.
    \3\ CWA 303(c)(3): If the Administrator, within sixty days after 
the date of submission of the revised or new standard, determines 
that such standard meets the requirements of this chapter, such 
standard shall thereafter be the water quality standard for the 
applicable waters of that State. If the Administrator determines 
that any such revised or new standard is not consistent with the 
applicable requirements of this chapter, he shall not later than the 
ninetieth day after the date of submission of such standard notify 
the State and specify the changes to meet such requirements. If such 
changes are not adopted by the State within ninety days after the 
date of notification, the Administrator shall promulgate such 
standard pursuant to paragraph (4) of this subsection.
    \4\ CWA 303(c)(4): The Administrator shall promptly prepare and 
publish proposed regulations setting forth a revised or new water 
quality standard for the navigable waters involved--(A) if a revised 
or new water quality standard submitted by such State under 
paragraph (3) of this subsection for such waters is determined by 
the Administrator not to be consistent with the applicable 
requirements of this chapter, or (B) in any case where the 
Administrator determines that a revised or new standard is necessary 
to meet the requirements of this chapter. The Administrator shall 
promulgate any revised or new standard under this paragraph not 
later than ninety days after he publishes such proposed standards, 
unless prior to such promulgation, such State has adopted a revised 
or new water quality standard which the Administrator determines to 
be in accordance with this chapter.
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    Under CWA section 304(a), the EPA periodically publishes criteria 
recommendations for states to consider when adopting water quality 
criteria for particular pollutants to meet the CWA section 101(a)(2) 
goals. In establishing numeric criteria, states should adopt water 
quality criteria based on the EPA's CWA section 304(a) criteria, 
section 304(a) criteria modified to reflect site-specific conditions, 
or other scientifically defensible methods (40 CFR 131.11(b)(1)). CWA 
section 303(c)(2)(B) \5\ requires states to adopt

[[Page 64061]]

numeric criteria for all toxic pollutants listed pursuant to CWA 
section 307(a)(1) for which the EPA has published 304(a) criteria, as 
necessary to support the states' designated uses.
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    \5\ CWA 303(c)(2)(B): Whenever a State reviews water quality 
standards pursuant to paragraph (1) of this subsection, or revises 
or adopts new standards pursuant to this paragraph, such State shall 
adopt criteria for all toxic pollutants listed pursuant to section 
1317(a)(1) of this title for which criteria have been published 
under section 1314(a) of this title, the discharge or presence of 
which in the affected waters could reasonably be expected to 
interfere with those designated uses adopted by the State, as 
necessary to support such designated uses. Such criteria shall be 
specific numerical criteria for such toxic pollutants. Where such 
numerical criteria are not available, whenever a State reviews water 
quality standards pursuant to paragraph (1) or revises or adopts new 
standards pursuant to this paragraph, such State shall adopt 
criteria based on biological monitoring or assessment methods 
consistent with information published pursuant to section 1314(a)(8) 
of this title. Nothing in this section shall be construed to limit 
or delay the use of effluent limitations or other permit conditions 
based on or involving biological monitoring or assessment methods or 
previously adopted numerical criteria.
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B. National Toxics Rule

    On December 22, 1992, the EPA promulgated Water Quality Standards; 
Establishment of Numeric Criteria for Priority Toxic Pollutants; 
States' Compliance at 57 FR 60848 (hereafter referred to as the 
National Toxics Rule or NTR).\6\ The NTR established chemical-specific 
numeric criteria for priority toxic pollutants for states that the EPA 
Administrator had determined were not in compliance with the 
requirements of CWA section 303(c)(2)(B). The NTR included selenium 
water quality criteria for the protection of aquatic life in the waters 
of the San Francisco Bay upstream to and including Suisun Bay and the 
Sacramento-San Joaquin Delta; and waters of Salt Slough, Mud Slough 
(north) and the San Joaquin River, Sack Dam to Vernalis. The NTR 
established the following criteria: For waters of the San Francisco Bay 
upstream to and including Suisun Bay and the Sacramento-San Joaquin 
Delta, a chronic criterion of 5 micrograms per liter ([micro]g/L) and 
an acute criterion of 20 [micro]g/L; for Salt Slough and Mud Slough 
(north), a chronic criterion of 5 [micro]g/L and an acute criterion of 
20 [micro]g/L; for the San Joaquin River from Sack Dam to the mouth of 
Merced River, an acute criterion of 20 [micro]g/L; and for the San 
Joaquin River from Sack Dam to Vernalis, a chronic criterion of 5 
[micro]g/L. All criteria are expressed in the total recoverable form of 
selenium.
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    \6\ The NTR is codified at 40 CFR 131.36.
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    The selenium criteria in the NTR were based on the EPA's CWA 
section 304(a) recommended criteria values that existed at the time. 
These recommendations are documented in the EPA's Ambient Water Quality 
Criteria for Selenium--1987, Office of Water, EPA-440/5-87-008, 
September 1987.
    The EPA derived the 1987 freshwater aquatic life recommended 
criteria values for selenium from observed impacts on fish populations 
at a contaminated lake, Belews Lake, in North Carolina. The lake, a 
cooling water reservoir, had been affected by selenium loads from a 
coal-fired power plant. Since aquatic life was exposed to selenium from 
both the water column and diet, the criteria reflect both types of 
exposure in Belews Lake. The EPA derived the 1987 saltwater aquatic 
life recommended criteria values for selenium using data from lab 
studies. The EPA calculated the criteria in accordance with the EPA's 
Guidelines for Deriving Numerical National Water Quality Criteria for 
the Protection of Aquatic Organisms and Their Uses, Office of Research 
and Development, 1985. The 1987 recommended freshwater criteria values 
for total recoverable selenium are 5 [micro]g/L (chronic) and 20 
[micro]g/L (acute), and the saltwater criteria values for total 
recoverable selenium are 71 [micro]g/L (chronic) and 290 [micro]g/L 
(acute).
    In the NTR, the EPA promulgated acute and chronic selenium criteria 
for the San Francisco Bay and Delta based on the 1987 freshwater 
recommended criteria values for selenium, even though the San Francisco 
Bay and Delta are marine and estuarine waters. The EPA used the more 
stringent freshwater values because of a concern that the saltwater 
criteria were not sufficiently protective ``based on substantial 
evidence that there are high levels of selenium bioaccumulation in San 
Francisco Bay and the saltwater criteria fail to account for food chain 
effects'' and ``utilization of the saltwater criteria for selenium in 
the San Francisco Bay/Delta would be inappropriate.'' (57 FR 60898).
    Since the NTR promulgation, the EPA has revised the 1987 CWA 
section 304(a) recommended criteria for selenium to better account for 
bioaccumulation through the food chain in different ecosystems. The EPA 
recently published a revised CWA section 304(a) freshwater recommended 
criterion for selenium: Final Aquatic Life Ambient Water Quality 
Criterion for Selenium--Freshwater 2016, US EPA, Office of Water, EPA 
822-R-16-006, June 2016. The 2016 recommended chronic freshwater 
criterion is comprised of four criterion elements, two of which are 
based on the concentration of selenium in fish tissue and two of which 
are based on the concentration of selenium in the water column. The 
recommended elements are: (1) A fish egg-ovary element of 15.1 mg/kg 
dry weight; (2) a fish whole-body element of 8.5 mg/kg dry weight and/
or a muscle element of 11.3 mg/kg dry weight; (3) a water column 
element of 3.1 [micro]g/L in lotic aquatic systems and 1.5 [micro]g/L 
in lentic aquatic systems; and (4) a water column intermittent element 
derived from the chronic water column element to account for potential 
chronic effects from short-term exposures (one value for lentic and one 
value for lotic aquatic systems).
    The EPA considered the methodology and information used to derive 
the 2016 CWA section 304(a) recommended selenium criterion, along with 
additional information specific to aquatic-dependent wildlife in 
California, in developing a revised selenium criterion for the fresh 
waters of California in this proposed rule.

C. California Toxics Rule

    On May 18, 2000, the EPA promulgated Water Quality Standards; 
Establishment of Numeric Criteria for Priority Toxic Pollutants for the 
State of California at 65 FR 31681 (hereafter referred to as the 
California Toxics Rule or CTR).\7\ The CTR established numeric water 
quality criteria for priority toxic pollutants for inland surface 
waters and enclosed bays and estuaries within California. As referenced 
earlier, CWA section 303(c)(2)(B) requires states to adopt numeric 
water quality criteria for priority toxic pollutants for which the EPA 
has issued CWA section 304(a) recommended criteria reflecting the 
latest scientific knowledge (referred to as CWA 304(a) recommended 
criteria), the presence or discharge of which could reasonably be 
expected to interfere with maintaining designated uses. The EPA 
promulgated the CTR to fill a gap in California WQS that was created in 
1994 when a State court overturned the State's water quality control 
plans which contained water quality criteria for priority toxic 
pollutants including selenium. The CTR included water quality criteria 
for priority toxic pollutants for inland surface waters and enclosed 
bays and estuaries within California. For the authority to promulgate 
the 2000 CTR, the EPA relied on an EPA Administrator's determination 
under section 303(c)(4) of the CWA, included in the 1997 CTR proposal, 
that numeric criteria are necessary in California to meet the 
requirements of section 303(c)(2)(B) to protect the State's

[[Page 64062]]

designated uses.\8\ The criteria that the EPA previously promulgated 
for California in the NTR,\9\ together with the criteria promulgated in 
the CTR and California's designated uses and antidegradation 
provisions, established WQS for priority toxic pollutants for inland 
surface waters and enclosed bays and estuaries in California.
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    \7\ The CTR is codified at 40 CFR 131.38.
    \8\ See the CTR preamble at section E. Rationale and Approach 
for Developing the Final Rule, 1. Legal Basis, ``EPA is using 
section 303(c)(4)(B) as the legal basis for today's final rule.'' 65 
FR 31687, May 18, 2000.
    \9\ The CTR Criteria Table at 40 CFR 131.38(b)(1) includes all 
water quality criteria previously promulgated in the NTR, so that 
readers can find all federally promulgated water quality criteria 
for California in one place. All criteria previously promulgated in 
the NTR are footnoted as such in the CTR.
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    As required by section 7 of the Endangered Species Act (ESA) (16 
U.S.C. 1531 et seq.), the EPA had consulted with the U.S. Fish and 
Wildlife Service (FWS) and the U.S. National Marine Fisheries Service 
(NMFS) (collectively, the Services) concerning the EPA's rulemaking 
actions for California. The EPA initiated consultation in 1994, and in 
March 2000, the Services issued a final Joint Biological Opinion. The 
final Joint Biological Opinion \10\ recorded commitments by the EPA to 
withhold promulgation of (i.e., reserve) the EPA's proposed acute \11\ 
freshwater aquatic life criterion for selenium in the final CTR and 
revise the CWA section 304(a) recommended acute and chronic aquatic 
life criteria for selenium and later update the criteria for California 
consistent with the revised recommendations. Subsequently, the EPA 
reserved the acute freshwater selenium criterion and finalized the 
chronic freshwater selenium criterion in the May 2000 CTR, as well as 
the acute and chronic saltwater selenium criteria.
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    \10\ Final Joint Biological Opinion dated March 24, 2000, from 
the National Marine Fisheries Service, Long Beach, California, and 
the U.S. Fish and Wildlife Service, Sacramento, California, 
concerning the EPA's final rule for the Promulgation of Water 
Quality Standards: Establishment of Numeric Criteria for Priority 
Toxic Pollutants for the State of California (CTR).
    \11\ The proposed freshwater acute selenium criterion in the CTR 
was as follows: The CMC = l/[(f1/CMC1) + (f2/CMC2)] where f1 and f2 
are the fractions of total selenium that are treated as selenite and 
selenate respectively, and f1 + f2 = 1. CMC1 and CMC2 are the CMCs 
for selenite and selenate, respectively, or 185.9 [micro]g/L and 
12.83 [micro]g/L, respectively. This criterion was in the total 
recoverable form. CMC is the continuous maximum concentration.
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    Because a distinct separation generally does not exist between 
freshwater and saltwater aquatic communities, the EPA further 
established the following rule in the CTR \12\ for determining which 
criteria to apply in certain situations: (1) The freshwater criteria 
apply at salinities of 1 part per thousand \13\ and below at locations 
where this occurs 95% or more of the time; (2) the saltwater criteria 
apply at salinities of 10 parts per thousand and above at locations 
where this occurs 95% or more of the time; and (3) at salinities 
between 1 and 10 parts per thousand, the more stringent of the two 
apply.
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    \12\ See the CTR at 40 CFR 131.38 (c)(3).
    \13\ In previous federal rules, including the NTR and the CTR, 
salinity was referred to using the units of parts per thousand 
(ppt). Since these rules were published, the scientific community 
has started referring to salinity in practical salinity units (psu). 
This proposed rule will stay consistent with the CTR terminology, 
but it should be noted that ppt is generally no longer used to 
describe salinity.
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    In addition to the NTR and CTR acute and chronic criteria for 
selenium discussed in the preceding paragraphs, California had also 
adopted site-specific acute and chronic criteria (objectives) in the 
lower San Joaquin River area. In 1990, prior to the NTR, the Central 
Valley Regional Water Quality Control Board (CVRWQCB) adopted, and the 
EPA approved, an acute selenium objective of 12 [micro]g/L maximum 
concentration for the San Joaquin River, mouth of Merced River to 
Vernalis, and a chronic site-specific objective for the Grassland Water 
District, the San Luis National Wildlife Refuge, and the Los Banos 
State Wildlife Refuge of 2 [micro]g/L monthly mean. Therefore, the 
State acute criterion is effective for the San Joaquin River, mouth of 
Merced River to Vernalis.
    In addition, the EPA did not promulgate a chronic criterion for the 
Grassland Water District, the San Luis National Wildlife Refuge, and 
the Los Banos State Wildlife Refuge in the CTR. The CVRWQCB 
subsequently amended its Basin Plan, to apply the chronic 2 [micro]g/L 
monthly mean selenium objective (and an acute 20 [micro]g/L maximum 
concentration objective) only to ``Salt Slough and constructed and 
reconstructed water supply channels in the Grassland watershed listed 
in Appendix 40 [of the CVRWQCB Basin Plan]'' (The Water Quality Control 
Plan (Basin Plan) for the California Regional Water Quality Control 
Board Central Valley Region, Fourth Edition, July 2016). The EPA 
approved this change to California's WQS under CWA section 303(c) in a 
letter dated May 24, 2000. The Basin Plan amendment also included a 
chronic site-specific objective of 5 [micro]g/L (4-day average) for Mud 
Slough (north) and for the San Joaquin River from Sack Dam to Vernalis, 
and an acute objective of 20 [micro]g/L for Mud Slough (north) and the 
San Joaquin River from Sack Dam to the mouth of the Merced River, to be 
consistent with the previously promulgated criteria in the NTR.
    This proposed rule does not apply to the San Joaquin River from 
Sack Dam to Vernalis, Mud Slough, or Salt Slough because they have 
applicable selenium criteria from the NTR and/or approved CVRWQCB site-
specific criteria (objectives). This proposed rule also does not apply 
to the constructed and reconstructed water supply channels in the 
Grassland watershed listed in Appendix 40 of the CVRWQCB's Basin Plan. 
The CVRWQCB's Staff Report for the Basin Plan amendment indicates that 
the existing chronic 2 [micro]g/L monthly mean objective is intended to 
protect both aquatic life and waterfowl from the toxic effects of 
selenium. This proposed rule does apply the revised chronic criterion 
to the waters of the San Luis National Wildlife Refuge and the Los 
Banos State Wildlife Refuge to protect aquatic life and wildlife from 
short-term and long-term exposures of selenium.
    The proposed rule also does not apply to surface waters that are 
tributaries to the Salton Sea. The Colorado River Regional Water 
Quality Control Board adopted, and the EPA approved on May 29, 2000, 
site-specific selenium water quality objectives ``for all surface 
waters that are tributaries to the Salton Sea.'' The site-specific 
objectives consist of an acute objective of 20 [micro]g/L one-hour 
average and a chronic objective of 5 [micro]g/L four-day average (The 
Water Quality Control Plan (Basin Plan) for the California Regional 
Water Quality Control Board Colorado River Basin Region, August 2017).
    The State of California has nine Regional Water Quality Control 
Boards (Regional Boards), each located in and overseeing different 
areas of the State. Each Regional Board has a regional water quality 
control plan (Basin Plan) that sets forth the EPA-approved designated 
(beneficial) uses for the waterbodies it oversees. Once the EPA 
finalizes the proposed criterion, the criterion becomes the applicable 
CWA-effective criterion for CWA implementation purposes by each of the 
Regional Boards.

D. Litigation

    In 2013, two organizations filed a legal complaint against the EPA 
in the United States District Court for the Northern District of 
California. The complaint was based in part on the fact that the EPA 
had previously determined, in the proposed CTR, that an acute criterion 
was necessary to implement section 303(c)(2)(B) of the CWA (62 FR 
42160, August 5, 1997) and the work to update the reserved

[[Page 64063]]

freshwater acute selenium criterion from the 2000 CTR had not yet been 
completed. The EPA ultimately entered into a consent decree resolving 
these claims in 2014 (Our Children's Earth Foundation and Ecological 
Rights Foundation v. U.S. Environmental Protection Agency, et al., 13-
cv-2857 (N.D. Cal., August 22, 2014)).
    Under the terms of the consent decree, the EPA committed to 
proposing selenium criteria for California fresh waters covered by the 
original CTR to protect aquatic life and aquatic-dependent wildlife by 
November 30, 2018. The consent decree also requires that the EPA 
request initiation of any necessary ESA section 7(a)(2) consultation 
with the Services on the proposed selenium criteria no later than nine 
months after the date the EPA proposes the criteria. Further, under the 
consent decree, the EPA is required to finalize its proposal of 
selenium criteria within six months of the later of either making a 
``no effect'' determination, receiving written concurrence from the 
Services, or concluding formal consultation with the Services. In the 
event that the EPA approves selenium criteria for the protection of 
aquatic life and aquatic-dependent wildlife submitted by California for 
all or any portion of fresh waters in the rest of California (i.e., all 
fresh waters not part of the San Francisco Bay and Delta) the EPA would 
no longer be obligated to propose or finalize criteria for such waters.
E. Selenium and Sources of Selenium
    Selenium is an element that occurs naturally in sediments of marine 
origin and enters the aquatic environment when rainwater comes into 
contact with deposits. Selenium is mobilized through anthropogenic 
activities such as agriculture irrigation, mining, and petroleum 
refining. It also comes into contact with the environment due to 
releases from holding ponds associated with mining. Selenium is emitted 
from power plants that burn coal or oil, selenium refineries, smelters, 
milling operations, and end-product manufacturers (e.g. semiconductor 
manufacturers).\14\ Once inorganic selenium is converted into a 
bioavailable form, it enters the food chain and can bioaccumulate. 
Depending on environmental conditions, one or another form of selenium 
such as selenate, selenite or organo-selenium, which differ in 
transformation rates and bioavailability, may predominate in the 
aquatic environment.
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    \14\ U.S. Department of Health and Human Services. Public Health 
Service. Agency for Toxic Substances and Disease Registry. 
Toxicological Profile for Selenium. September 2003 (https://www.atsdr.cdc.gov/toxprofiles/tp92.pdf).
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    Selenium is an essential micronutrient and low levels of selenium 
in the diet are required for normal cellular function in almost all 
animals. However, selenium at amounts not much above the required 
nutritional levels can have toxic effects on aquatic life and aquatic-
dependent wildlife, making it one of the most toxic of the biologically 
essential elements. Egg-laying vertebrates have a lower tolerance than 
do mammals, and the transition from levels of selenium that are 
biologically essential to those that are toxic for these species occurs 
across a relatively narrow range of exposure concentrations. (see Final 
Aquatic Life Ambient Water Quality Criteria for Selenium--Freshwater 
2016, US EPA, Office of Water, EPA 822-R-16-006, June 2016). Elevated 
selenium levels above what is nutritionally required in fish and other 
wildlife inhibit normal growth and reduce reproductive success through 
effects that lower embryo survival, most notably teratogenesis (i.e., 
embryo/larval deformities). The deformities associated with exposure to 
elevated selenium in fish may include skeletal, craniofacial, and fin 
deformities, and various forms of edema that result in mortality. 
Elevated selenium exposure in birds can reduce reproductive success 
including decreased fertility, reduced egg hatchability (embryo 
mortality), and increased incidence of deformities in embryos.
    Scientific studies \15\ indicate that selenium toxicity to aquatic 
life and aquatic-dependent wildlife is driven by diet (i.e., the 
consumption of selenium-contaminated prey) rather than by direct 
exposure to dissolved selenium in the water column. Unlike other 
bioaccumulative contaminants such as mercury, the single largest step 
in selenium accumulation in aquatic environments occurs at the base of 
the food web where algae and other microorganisms accumulate selenium 
from water. The vulnerability of a species to selenium toxicity is 
determined by a number of factors in addition to the amount of 
contaminated prey consumed. A species' sensitivity to selenium, its 
population status, and the duration, timing and life stage of exposure 
are all factors to consider. In addition, the hydrologic conditions and 
water chemistry of a water body affect bioaccumulation; in general, 
slow-moving, calm waters or lentic waters enhance the production of 
bioavailable forms of selenium (selenite), while faster-moving waters 
or lotic waters limit selenium uptake given the rapid movement and 
predominant form of selenium (selenate). The EPA considered these and 
other factors in determining the proposed selenium criterion for 
California.
---------------------------------------------------------------------------

    \15\ Scientific studies used in the development of this 
rulemaking can be found in this proposed rule's docket, as well as 
dockets EPA-HQ-OW-2004-0019 and EPA-HQ-OW-2015-0392.
---------------------------------------------------------------------------

Sources of Selenium in California
    Selenium is found in the upper Cretaceous and Tertiary marine and 
sedimentary deposits that form the California Coast Ranges and inland 
Central Valley basin. Sedimentary rocks, particularly shales, have the 
highest naturally occurring selenium content and the natural weathering 
of geologic strata containing selenium can lead to selenium leaching 
into groundwater and surface water. Two major categories of 
anthropogenic activities are known to cause increased selenium 
mobilization and introduction into aquatic systems. The first is human 
disturbances to the geological sedimentary deposits; the second is 
irrigation of selenium-rich soils. Additional sources include five oil 
refineries along the San Francisco Bay, which are not included in the 
scope of this proposal.
    In California, areas with Tertiary and Cretaceous marine 
sedimentary deposits are known to have elevated selenium. Watersheds in 
these areas may have elevated selenium levels in water, especially if 
human disturbances to the geological sedimentary deposits in these 
areas are high. For instance, human disturbances have included 
expanding the width and depth of open drainage channels for flood 
control purposes in agricultural and urbanized areas and conducting 
construction activities in the upland hills that contain marine shales. 
These activities have disrupted and exposed the underlying selenium-
bearing marine sedimentary deposits subjecting them to erosion, 
weathering, and transport to downslope areas in the watershed.
    Irrigation of selenium-rich soils for crop production in arid and 
semi-arid regions of California can mobilize selenium and move it off-
site in drainage water that has leached through soil. Where deposits of 
Cretaceous marine shales occur, they can weather to produce high 
selenium soils. In semi-arid areas of California, irrigation water 
applied to soils containing soluble selenium can leach selenium. The 
excess water (from tile drains to irrigation return flow) containing 
selenium can be discharged into basins, ponds, or streams. For example,

[[Page 64064]]

elevated selenium levels at the Kesterson Reservoir in California 
originated from agricultural irrigation return flow collected in tile 
drains that discharged into the reservoir.

III. Proposed Criterion

A. Approach

    In 2016, the EPA updated its CWA section 304(a) recommendation for 
a chronic aquatic life criterion for selenium for freshwater, based on 
the latest scientific knowledge on selenium toxicity and 
bioaccumulation (Final Aquatic Life Ambient Water Quality Criteria for 
Selenium--Freshwater 2016, US EPA, Office of Water, EPA 822-R-16-006, 
June 2016). This information was not available when the EPA finalized 
the NTR or the CTR in 1992 and 2000, respectively. The EPA is now 
proposing a revised chronic selenium criterion to protect aquatic life 
and aquatic-dependent wildlife for the fresh waters of California based 
on this latest scientific knowledge and consistent with its obligation 
under the consent decree.
    This chronic freshwater selenium criterion will apply to California 
waters in a manner consistent with the CTR. The freshwater and 
saltwater aquatic life criteria listed in the CTR apply as follows: (1) 
The freshwater criteria apply at salinities of 1 part per thousand and 
below at locations where this occurs 95% or more of the time; (2) 
saltwater criteria apply at salinities of 10 parts per thousand and 
above at locations where this occurs 95% more of the time; and (3) at 
salinities between 1 and 10 parts per thousand the more stringent of 
the two apply.
    The proposed criterion would establish levels of selenium that 
protect California's aquatic life and aquatic-dependent wildlife 
designated (beneficial) uses for fresh waters of California consistent 
with California's implementation of the CTR. California's applicable 
designated uses for the protection of aquatic life and aquatic-
dependent wildlife are listed in Table 2.
---------------------------------------------------------------------------

    \16\ Refer to document titled, ``Applicable Designated 
(Beneficial) Uses for California,'' in the docket associated with 
this rulemaking, to find designated uses captured in the California 
Regional Water Quality Control Boards' Water Quality Control Plans 
(i.e., Regional Boards' Basin Plans).

  Table 2--Applicable Designated (Beneficial) Uses for California \16\
------------------------------------------------------------------------
             Use                   Abbreviation          Definition
------------------------------------------------------------------------
Warm Freshwater Habitat......  WARM                 Uses of water that
                                                     support warm water
                                                     ecosystems
                                                     including, but not
                                                     limited to,
                                                     preservation or
                                                     enhancement of
                                                     aquatic habitats,
                                                     vegetation, fish,
                                                     or wildlife,
                                                     including
                                                     invertebrates.
Cold Freshwater Habitat......  COLD                 Uses of water that
                                                     support cold water
                                                     ecosystems
                                                     including, but not
                                                     limited to,
                                                     preservation or
                                                     enhancement of
                                                     aquatic habitats,
                                                     vegetation, fish,
                                                     or wildlife,
                                                     including
                                                     invertebrates.
Migration of Aquatic           MIGR                 Uses of water that
 Organisms.                                          support habitats
                                                     necessary for
                                                     migration or other
                                                     temporary
                                                     activities by
                                                     aquatic organisms,
                                                     such as anadromous
                                                     fish.
Spawning, Reproduction, and/   SPWN                 Uses of water that
 or Early Development.                               support high
                                                     quality aquatic
                                                     habitats suitable
                                                     for reproduction
                                                     and early
                                                     development of
                                                     fish.
Estuarine Habitat............  EST                  Uses of water that
                                                     support estuarine
                                                     ecosystems
                                                     including, but not
                                                     limited to,
                                                     preservation or
                                                     enhancement of
                                                     estuarine habitats,
                                                     vegetation, fish,
                                                     shellfish, or
                                                     wildlife (e.g.,
                                                     estuarine mammals,
                                                     waterfowl,
                                                     shorebirds).
Wildlife Habitat.............  WILD                 Uses of water that
                                                     support terrestrial
                                                     ecosystems
                                                     including, but not
                                                     limited to,
                                                     preservation or
                                                     enhancement of
                                                     terrestrial
                                                     habitats,
                                                     vegetation,
                                                     wildlife (e.g.,
                                                     mammals, birds,
                                                     reptiles,
                                                     amphibians,
                                                     invertebrates), or
                                                     wildlife water and
                                                     food sources.
Rare, Threatened, or           RARE                 Uses of water that
 Endangered Species.                                 support habitats
                                                     necessary, at least
                                                     in part, for the
                                                     survival and
                                                     successful
                                                     maintenance of
                                                     plant or animal
                                                     species established
                                                     under state or
                                                     federal law as
                                                     rare, threatened or
                                                     endangered.
------------------------------------------------------------------------

B. Administrator's Determination of Necessity

    As noted above, as part of the prior CTR rulemaking, the EPA 
invoked its authority under CWA section 303(c)(4)(B) when it proposed 
acute and chronic selenium criteria for fresh waters in California not 
subject to numeric criteria. The basis for that 303(c)(4)(B) 
determination was California's lack of numeric criteria, including 
selenium criteria as required by CWA section 303(c)(2)(B), which 
directs states to adopt numeric criteria for those toxic pollutants for 
which the EPA has published CWA 304(a) recommended criteria. In 1997, 
the EPA proposed acute and chronic aquatic life criteria for selenium 
based on the EPA's then-current CWA 304(a) recommended criteria. 
Through the course of that rulemaking, the EPA consulted with the 
Services pursuant to section 7(a) of the Endangered Species Act. As 
part of that consultation process, the EPA committed to reserving (not 
promulgating) the proposed acute criterion. Because the EPA did not 
finalize the proposed acute criterion, nor did it reconsider the 
accompanying section 303(c)(4)(B) determination, the EPA remained 
subject to a statutory duty to promulgate an acute selenium criterion 
for California. The EPA did promulgate chronic selenium criteria in 
2000, but also committed to proposing revised chronic criteria by 2003. 
The Services incorporated the EPA's commitments as Terms and Conditions 
in the final biological opinion on the effects of the final 
promulgation of the CTR.
    Today's proposal of a revised chronic selenium criterion is 
necessary to complete actions initiated pursuant to the Administrator's 
1997 and 2000 CTR determinations. The EPA is proposing a revised 
numeric selenium criterion, to comply with CWA section 303(c)(2)(B). 
The EPA is proposing a chronic criterion for California based on the 
EPA's current CWA 304(a) recommended criterion for selenium, which only 
includes a chronic criterion. The current science shows that an acute 
criterion is not necessary to protect from the lethal effects of 
selenium if a protective chronic criterion is in place, which by 
definition protects against

[[Page 64065]]

sublethal effects and effects of short-term elevations of selenium that 
are introduced into the food web and could result in chronic effects. 
Therefore, if a protective chronic selenium criterion, such as the EPA 
is proposing today, is ultimately promulgated, an acute criterion would 
no longer be necessary to meet the requirements of the CWA, and so the 
Administrator's determinations contained in the 1997 and 2000 preambles 
to the CTR will be negated insofar as they called for the promulgation 
of an acute selenium criterion.

C. Proposed Criterion

    Water quality criteria establish the maximum allowable pollutant 
level that is protective of the designated uses of a water body. States 
adopt or, as in this case, the EPA may promulgate criteria as part of 
WQS. Under the CWA, WQS are used to derive water quality-based effluent 
limitations (WQBELs) in permits for point source dischargers, thereby 
limiting the amount of pollutants that may be discharged into a water 
body to maintain its designated uses. The EPA is proposing a selenium 
water quality criterion for California comprised of criterion elements 
of fish tissue, bird tissue, and a performance-based approach to be 
used by California to translate the tissue criterion elements into 
protective water column elements on a site-specific basis. The EPA is 
proposing selenium fish and bird tissue elements because they reflect 
biological uptake through diet, the predominant pathway for selenium 
toxicity, and because they are most predictive of the observed 
biological endpoint of concern: Reproductive toxicity.
    The EPA is proposing the freshwater selenium criterion in 
California that is depicted in Table 3. The EPA is proposing its 
recommended 2016 CWA section 304(a) selenium criterion for freshwater 
with the addition of a bird tissue criterion element and the 
replacement of the 304(a) selenium monthly average exposure water 
column criterion element with a performance-based approach \17\ for 
translating the tissue elements into corresponding water-column 
elements on a site-specific basis. This performance-based approach 
maximizes the flexibility for the State to develop water-column 
translations specifically tailored to each individual waterbody. The 
available data indicate that applying the criterion in Table 3 would 
protect aquatic life and aquatic-dependent wildlife from the toxic 
effects of selenium, recognizing that fish tissue elements and the bird 
tissue element supersede any translated site-specific water column 
elements and that the fish egg-ovary element supersedes all other fish 
tissue elements. The proposed tissue criterion elements consist of a 
bird egg criterion element of 11.2 mg/kg dry weight, a fish egg-ovary 
criterion element of 15.1 mg/kg dry weight, a fish whole-body criterion 
element of 8.5 mg/kg dry weight or a fish muscle criterion element of 
11.3 mg/kg dry weight. The fish tissue and bird tissue criterion 
elements were developed to protect aquatic and aquatic-dependent 
wildlife populations from impacts caused by selenium. Tissue data 
provide instantaneous point measurements that reflect integrative 
accumulation of selenium over time and space in fish or birds at a 
given site. California will have flexibility in how they interpret a 
discrete fish sample to represent a given species' population at a 
site. Generally, fish and bird tissue samples collected to calculate 
average tissue concentrations (often in composites) for a species at a 
site are collected in one sampling event, or over a short interval due 
to logistical constraints and cost for obtaining samples. The proposed 
performance-based approach consists of a methodology, Draft Translation 
of Selenium Tissue Criterion Elements to Site-Specific Water Column 
Criterion Elements for California Version 1, August 8, 2018, available 
in the docket for this rulemaking, to translate the tissue criterion 
elements to site-specific water column criterion elements (discussed in 
greater detail below Table 3). The EPA is also proposing an 
intermittent exposure water column element that would be derived from 
the site-specific water column criterion elements. The EPA is proposing 
that the bird tissue element be independently applicable from and 
equivalent to the fish tissue elements, but that all tissue elements 
will supersede translated water column elements for the specific taxon 
when both are measured.
---------------------------------------------------------------------------

    \17\ A performance-based approach relies on the state or 
authorized tribe adopting a process (i.e., a criterion derivation 
methodology, with associated implementation procedures) rather than 
a specific outcome (e.g., numeric criterion or concentration of a 
pollutant) in its water quality standards regulation. In instances 
where the EPA promulgates a water quality standard (including a 
performance-based approach) for a state or authorized tribe, the EPA 
is held to the same requirements and expectations for that water 
quality standard as the state or authorized tribe. The concept of a 
performance-based approach was first described in the Federal 
Register Notice EPA Review and Approval of State and Tribal Water 
Quality Standards--Final Rule (65 FR 24641-24653; April 27, 2000).
---------------------------------------------------------------------------

    The EPA is proposing the following criterion:
BILLING CODE 6560-50-P

[[Page 64066]]

[GRAPHIC] [TIFF OMITTED] TP13DE18.007

BILLING CODE 6560-50-C
Performance-Based Approach for Translating Tissue Criterion Elements to 
Site-Specific Water Column Criterion Elements
    As part of the proposed criterion depicted in Table 3, the EPA is 
including a methodology, incorporated by reference, to translate the 
fish tissue criterion elements' concentrations and the bird tissue 
criterion element's concentration into site-specific water column 
concentrations. This is considered a performance-based approach to 
developing site-specific water column elements consistent with other 
elements of the criterion. This set of binding procedures for 
translating fish and bird tissue criterion elements is detailed in the 
Draft Translation of Selenium Tissue Criterion Elements to Site-
Specific Water Column Criterion Elements for California, Version 1, 
August 8, 2018 and is located in the docket for this rulemaking. The 
performance-based approach provides two methodologies for deriving 
site-specific water column criterion elements: The mechanistic modeling 
approach and the empirical bioaccumulation factor (BAF) approach.

[[Page 64067]]

    The mechanistic modeling approach uses scientific knowledge of the 
physical and chemical processes underlying bioaccumulation to establish 
a relationship between the concentrations of selenium in the water 
column and the concentration of selenium in the tissue of aquatic and 
aquatic-dependent organisms. The mechanistic modeling approach enables 
formulation of site-specific models of trophic transfer of selenium 
through aquatic food webs and translation of the tissue elements into 
an equivalent site-specific water column selenium element. It is also 
the approach used to develop the 2016 CWA 304(a) recommended selenium 
criterion water column elements.
    The empirical BAF approach establishes a site-specific relationship 
between water column selenium concentrations and fish (or bird) tissue 
selenium concentrations by measuring both directly and using the 
relationship between them to determine a site-specific water column 
criterion element.
    If, after soliciting comment, the EPA finalizes a selenium 
criterion that includes the proposed performance-based approach as part 
of the federal promulgation, each resulting site-specific water column 
criterion element would be applicable for CWA purposes, without the 
need for EPA approval under CWA section 303(c). Importantly, for public 
transparency, the EPA recommends that California maintain a list of the 
resulting site-specific water column criterion elements and the 
underlying data used for their respective derivation on their publicly 
accessible website.
    The proposed chronic selenium criterion applies to the entire 
aquatic community, including fish, amphibians, invertebrates, and 
aquatic-dependent wildlife. Based on the analysis in the accompanying 
Technical Support Document (TSD) to this proposed rule (Aquatic Life 
and Aquatic-Dependent Wildlife Selenium Water Quality Criterion for 
Fresh Waters of California) and the EPA's previous work (Final Aquatic 
Life Ambient Water Quality Criteria for Selenium--Freshwater 2016, US 
EPA, Office of Water, EPA 822-R-16-006, June 2016), as well as 
currently available data, fish and birds are considered the most 
sensitive taxa to selenium effects. Selenium criterion elements based 
on fish tissue (egg-ovary, whole body, and/or muscle) or bird egg 
tissue data will override the performance-based translated water column 
concentrations because fish and bird tissue concentrations provide the 
most robust and direct information on potential selenium effects in 
fish and birds.
    Although selenium may cause acute toxicity at high concentrations, 
i.e., toxicity from a brief but highly elevated concentration of 
selenium in the water, chronic dietary exposure poses the highest risk 
to aquatic life and aquatic-dependent wildlife. Chronic toxicity occurs 
primarily through maternal transfer of selenium to eggs and causes 
subsequent reproductive effects, such as larval and embryo structural 
deformity, edema, and mortality. Because chronic effects of selenium 
are observed at much lower concentrations than acute effects, the 
chronic criterion is also expected to protect aquatic and aquatic-
dependent communities from any potential acute effects of selenium. 
However, some high concentration, short-term exposures could be 
detrimental by causing significant long-term, residual, bioaccumulative 
effects (i.e., by the introduction of a significant selenium load into 
the system). Therefore, the EPA is also proposing the performance-based 
approach be used to address intermittent exposure criterion to selenium 
to prevent long-term detrimental effects from these high concentration, 
short-term exposures. The EPA's proposed intermittent exposure 
criterion element should be derived mathematically, from the 
performance-based site-specific monthly water column elements for 
lentic and/or lotic waters using the equation shown in Table 3. The 
equation expresses the intermittent exposure water criterion element in 
terms of the 30-day average chronic water criterion element, for a 
lentic or lotic system, as appropriate, while accounting for the 
fraction in days of any 30-day period the intermittent spikes occur and 
for the background concentration occurring during the remaining time. 
The intermittent exposure criterion calculation is consistent with the 
EPA's national 304(a) recommended freshwater aquatic life criterion for 
selenium (see Section 3.3.) and is meant to be used in situations where 
a noncontinous discharge is present in the water body of interest.
    The EPA solicits comment on the Draft Translation of Selenium 
Tissue Criterion Elements to Site-Specific Water Column Criterion 
Elements for California, Version 1, August 8, 2018 and how it has been 
applied in this proposed rule and requests any additional information 
for consideration by the EPA. The EPA specifically solicits comment on 
whether it would be appropriate to include a method for a larger scale 
(e.g., ecoregional or state-wide) water column translation from fish or 
bird egg tissue in a performance-based approach, and if so, what 
methods are available and appropriate for this large scale translation. 
Such an approach would need, for example, methods for selecting sites 
from a larger area and would need to specify in the performance-based 
approach how decisions will be made using information from multiple 
sites.
    Additionally, the EPA is soliciting public comment on an 
alternative to the proposed criterion whereby the criterion would be 
expressed in the same manner as in this proposed rule (same bird 
tissue, fish tissue, and intermittent exposure criterion elements as 
presented in Table 3), however, in addition to the performance-based 
approach to translate site-specific water column criterion elements, 
the EPA would include the water column criterion elements from the 
Agency's 2016 CWA section 304(a) selenium criterion for freshwater: A 
lotic water column criterion element of 3.1 [micro]g/L and a lentic 
water column criterion element of 1.5 [micro]g/L. The derivation of 
these water column criterion elements is described in detail in the 
accompanying TSD to this proposed rule and the EPA's previous work in 
its 2016 CWA section 304(a) selenium criterion for freshwater. The EPA 
also solicits comment on an alternative that would be expressed in the 
same manner as the proposed criterion (same bird tissue, fish tissue, 
and intermittent exposure criterion elements as presented in Table 3), 
and include the EPA water column criterion elements from the Agency's 
2016 CWA section 304(a) selenium criterion for freshwater, instead of 
including the performance-based approach.
    The EPA also solicits comment on the criterion structure whereby 
rather than proposing one criterion that protects applicable aquatic 
life and wildlife designated uses, the rule, if finalized, would 
consist of two separate criteria with one intended to protect the 
applicable aquatic life designated uses and one intended to protect the 
applicable wildlife designated uses. The two separate criteria would be 
structured as follows: (1) An aquatic life criterion, consisting of the 
same fish tissue elements and performance-based approach presented in 
Table 3, to protect the applicable aquatic life designated uses; and 
(2) an aquatic-dependent wildlife criterion, consisting of the same 
bird tissue element and performance-based approach presented in Table 
3, to protect the applicable wildlife designated uses. The EPA solicits 
comment on the criterion structure and whether one criterion or two 
separate criteria are preferred for

[[Page 64068]]

implementation reasons. This approach could also utilize either the 
performance-based approach to translate tissue elements to site-
specific water-column elements or the water-column elements from the 
Agency's 2016 CWA section 304(a) selenium criterion for freshwater. If 
the proposed rule is finalized as currently written, one criterion (as 
shown in Table 3) would be used to protect both aquatic life and 
aquatic-dependent wildlife designated uses in the waters covered by 
this proposed rule, as opposed to two separate criteria, each intended 
to protect a separate designated use.

D. Implementation

    The EPA is proposing that for purposes of assessing attainment of 
the criterion, the bird tissue element be independently applicable from 
the fish tissue elements (i.e., if the bird tissue element is exceeded, 
the criterion is not being attained for the applicable wildlife 
designated use), but that all tissue elements will supersede translated 
water column elements for the specific taxon when both are measured 
(i.e., if both of the tissue elements are being met, the criterion is 
being attained even if the water column element is exceeded). 
Additionally, fish egg-ovary data supersedes any whole-body, muscle, or 
translated water column element data for that taxon when fish-egg ovary 
are measured (i.e., if the fish egg-ovary element is being met, the 
criterion is being attained even if the whole-body, muscle, or water 
column elements are not being met). Similarly, the bird tissue element 
supersedes translated water column elements for that taxon when both 
are measured. California has flexibility in how to evaluate individual 
and composite samples for each taxon. The State's assessment 
methodology should make its decision-making process in this situation 
clear. This construct is equivalent to the EPA's CWA 304(a) recommended 
selenium criterion in that tissue criterion elements have primacy over 
water column criterion elements.
    Selenium concentrations in fish and bird tissue are primarily a 
result of selenium bioaccumulation via dietary exposure. Because of 
this, fish and bird tissue concentrations in waters with new inputs of 
selenium may not fully represent potential effects on fish, birds, and 
the aquatic ecosystem. New inputs are defined as new anthropogenic 
activities resulting in the release of selenium into a lentic or lotic 
aquatic system. New inputs do not refer to seasonal variability of 
selenium that occurs naturally within a system (e.g. spring run-off 
events or precipitation-driven pulses). In this circumstance fish 
tissue data and bird tissue data may not fully represent potential 
effects on the aquatic ecosystem, making the use of a translated water 
column element derived using the mechanistic model portion of the 
performance-based approach more appropriate to protect the entire 
aquatic ecosystem.
    Because tissue concentrations alone may present challenges when 
attempting to incorporate them directly in NPDES permits, the EPA is 
also proposing a performance-based approach for California to use to 
translate tissue elements to site-specific water column concentrations. 
These translated water column criterion concentrations would not 
prevent California from also using the tissue criterion elements for 
monitoring and regulation of pollutant discharges. In implementing the 
water quality criterion for selenium under the NPDES permits program, 
California may need to establish additional procedures due to the 
unique components of the selenium criterion. Where California uses a 
translated selenium water column concentration only (as opposed to 
using both the water column and fish tissue or bird tissue elements) 
for conducting reasonable potential (RP) determinations and 
establishing WQBELs per 40 CFR 122.44(d), existing implementation 
procedures used for other aquatic life protection criteria may be 
appropriate. However, if California also decides to use the selenium 
fish tissue criterion elements and bird tissue criterion element for 
NPDES permitting purposes, additional state WQS implementation 
procedures (IPs) will likely be needed to determine the need for and 
development of WQBELs necessary to ensure that the tissue criterion 
element(s) are met.

E. Incorporation by Reference

    The EPA is proposing that the final EPA regulatory text will 
incorporate one EPA document by reference. In accordance with the 
requirements of 1 CFR 51.5, the EPA is proposing to incorporate by 
reference the final version of the EPA's current Draft Translation of 
Selenium Tissue Criterion Elements to Site-Specific Water Column 
Criterion Elements for California, Version 1, August 8, 2018, discussed 
in Section III.C. of this preamble. The EPA has made, and will continue 
to make, this document available electronically through 
www.regulations.gov at the docket associated with this rulemaking and 
at the appropriate EPA office (see the ADDRESSES section of this 
preamble for more information).

IV. Endangered Species Act

    Pursuant to section 7(a)(2) of the Endangered Species Act (ESA), 
the EPA is consulting with the FWS and NMFS concerning the EPA's 
rulemaking action for the selenium water quality criterion in 
California. The EPA will transmit to the Services documentation that 
supports the selenium water quality criterion in this proposed rule. As 
a result of this consultation, the EPA may modify some provisions of 
this proposed rule.

V. Applicability of the EPA Promulgated Water Quality Standards When 
Final

    Under the CWA, Congress gave states primary responsibility for 
developing and adopting WQS for their waters (CWA section 303(a)-(c)). 
Although the EPA is proposing a selenium criterion for the protection 
of aquatic life and aquatic-dependent wildlife for the fresh waters of 
California, California continues to have the option to adopt and submit 
to the EPA selenium criteria (objectives) for the State's waters 
consistent with CWA section 303(c) and the EPA's implementing 
regulations at 40 CFR part 131. The EPA encourages California to 
expeditiously adopt selenium criteria. Consistent with CWA section 
303(c)(4) and the terms of the consent decree, if California adopts and 
submits selenium criteria for the protection of aquatic life and 
aquatic-dependent wildlife, and the EPA approves such criteria before 
finalizing this proposed rule, the EPA would not proceed with the 
promulgation for those waters for which the EPA approves California's 
criteria. Under those circumstances, federal promulgation would no 
longer be necessary to meet the requirements of the Act.
    If the EPA finalizes this proposed rule and California subsequently 
adopts and submits selenium criteria for the protection of aquatic and 
aquatic-dependent wildlife for California, the EPA would approve 
California's criteria if those criteria meet the requirements of 
section 303(c) of the CWA and the EPA's implementing regulation at 40 
CFR part 131. If the EPA's federally-promulgated criteria are more 
stringent than the State's criteria, the EPA's federally-promulgated 
criteria are and will be the applicable water quality standard for 
purposes of the CWA until the Agency withdraws those federally-
promulgated standards. The EPA would expeditiously undertake such a 
rulemaking to withdraw the federal criteria if and when California 
adopts and the EPA approves corresponding criteria. After the EPA's 
withdrawal of

[[Page 64069]]

federally promulgated criteria, the State's EPA-approved criteria would 
become the applicable criteria for CWA purposes. If the State's adopted 
criteria are as stringent or more stringent than the federally-
promulgated criteria, then the State's criteria would become the CWA 
applicable WQS upon the EPA's approval (40 CFR 131.21(c)).

VI. Implementation and Alternative Regulatory Approaches

    The federal WQS regulation at 40 CFR part 131 provides several 
tools that California has available to use at its discretion when 
implementing or deciding how to implement these aquatic life criteria, 
once finalized. Among other things, the EPA's WQS regulation: (1) 
Specifies how states and authorized tribes establish, modify or remove 
designated uses, (2) specifies the requirements for establishing 
criteria to protect designated uses, including criteria modified to 
reflect site-specific conditions, (3) authorizes and provides 
regulatory guidelines for states and authorized tribes to adopt WQS 
variances that provide time to achieve the applicable WQS, and (4) 
allows states and authorized tribes to authorize the use of compliance 
schedules in NPDES permits to meet WQBELs derived from the applicable 
WQS. Each of these approaches are discussed in more detail in the next 
sections.
Designated Uses
    The EPA's proposed selenium criterion applies to fresh waters of 
California where the protection of aquatic life and aquatic-dependent 
wildlife are designated uses. The federal regulations at 40 CFR 131.10 
provide information on establishing, modifying, and removing designated 
uses. If California removes designated uses such that no aquatic life 
or aquatic-dependent wildlife uses apply to any particular water body 
segment affected by this rule and adopts the highest attainable 
use,\18\ the State must also adopt criteria to protect the newly 
designated highest attainable use consistent with 40 CFR 131.11. It is 
possible that criteria other than the federally promulgated criteria 
would protect the highest attainable use. If the EPA finds removal or 
modification of the designated use and the adoption of the highest 
attainable use and criteria to protect that use to be consistent with 
CWA section 303(c) and the implementing regulation at 40 CFR part 131, 
the Agency would approve the revised WQS. The EPA would then undertake 
a rulemaking to withdraw the corresponding federal WQS for the relevant 
water(s).
---------------------------------------------------------------------------

    \18\ If a state or authorized tribe adopts a new or revised WQS 
based on a required use attainability analysis, then it must also 
adopt the highest attainable use (40 CFR 131.10(g)). Highest 
attainable use is the modified aquatic life, wildlife, or recreation 
use that is both closest to the uses specified in section 101(a)(2) 
of the Act and attainable, based on the evaluation of the factor(s) 
in 40 CFR 131.10(g) that preclude(s) attainment of the use and any 
other information or analyses that were used to evaluate 
attainability. There is no required highest attainable use where the 
state demonstrates the relevant use specified in section 101(a)(2) 
of the Act and sub-categories of such a use are not attainable (see 
40 CFR 131.3(m)).
---------------------------------------------------------------------------

Site-Specific Criteria
    The regulations at 40 CFR 131.11 specify requirements for modifying 
water quality criteria to reflect site-specific conditions. In the 
context of this rulemaking, a site-specific criterion (SSC) is an 
alternative value to the federal selenium criterion that would be 
applied on an area-wide or water body-specific basis that meets the 
regulatory test of protecting the designated uses, being scientifically 
defensible, and ensuring the protection and maintenance of downstream 
WQS. A SSC may be more or less stringent than the otherwise applicable 
federal criterion. A SSC may be called for when further scientific data 
and analyses indicate that a different selenium concentration (e.g., a 
different fish tissue or bird tissue criterion element) may be needed 
to protect the aquatic life and aquatic-dependent wildlife-related 
designated uses in a particular water body or portion of a water body.
WQS Variances
    California's WQS provide sufficient authority to apply WQS 
variances when implementing a federally promulgated criterion for 
selenium, as long as such WQS variances are adopted consistent with 40 
CFR 131.14 and submitted to the EPA for review and approval under CWA 
section 303(c). Federal regulations at 40 CFR 131.14 define a WQS 
variance as a time-limited designated use and criterion, for a specific 
pollutant or water quality parameter, that reflects the highest 
attainable condition during the term of the WQS variance. WQS variances 
adopted in accordance with 40 CFR 131.14 (including a public hearing 
consistent with 40 CFR 25.5) provide a flexible but defined pathway for 
states and authorized tribes to meet their NPDES permit obligations by 
allowing dischargers the time they need (as demonstrated by the state 
or authorized tribe) to make incremental progress toward meeting WQS 
that are not immediately attainable but may be in the future. When 
adopting a WQS variance, states and authorized tribes specify the 
interim requirements of the WQS variance by identifying a quantitative 
expression that reflects the highest attainable condition (HAC) during 
the term of the WQS variance, establishing the term of the WQS 
variance, and describing the pollutant control activities expected to 
occur over the specified term of the WQS variance. WQS variances help 
states and authorized tribes focus on improving water quality, rather 
than pursuing a downgrade of the underlying water quality goals through 
modification or removal of a designated use, as a WQS variance cannot 
lower currently attained water quality. WQS variances provide a legal 
avenue by which NPDES permit limits can be written to comply with the 
WQS variance rather than the underlying WQS for the term of the WQS 
variance. If dischargers are still unable to meet the WQBELs derived 
from the applicable WQS once a WQS variance term is complete, the 
regulation allows the state and authorized tribe to adopt a subsequent 
WQS variance if it is adopted consistent with 40 CFR 131.14. The EPA is 
proposing a criterion that applies to use designations that California 
has already established. California's WQS currently include the 
authority to use WQS variances when implementing criteria, as long as 
such WQS variances are adopted consistent with 40 CFR 131.14. 
California may use EPA-approved WQS variance procedures when adopting 
such WQS variances.
Compliance Schedules
    The EPA's regulations at 40 CFR 122.47 and 40 CFR 131.15 address 
how permitting authorities can use permit compliance schedules in NPDES 
permits if dischargers need additional time to undertake actions like 
facility upgrades or operation changes to meet their WQBELs based on 
the applicable WQS. The EPA's regulation at 40 CFR 122.47 allows 
permitting authorities to include compliance schedules in their NPDES 
permits, when appropriate and where authorized by the state or 
authorized tribe, in order to provide a discharger with additional time 
to meet its WQBELs implementing applicable WQS. The EPA's regulation at 
40 CFR 131.15 requires that states and authorized tribes that choose to 
allow the use of NPDES permit compliance schedules adopt specific 
provisions authorizing their use and obtain the EPA approval under CWA 
section 303(c) to ensure that a decision to allow permit compliance 
schedules is transparent and allows for public input (80 FR 51022, 
August 21, 2015). The EPA's approval of the state's or authorized 
tribe's permit compliance schedule authorizing provision (CSAP)

[[Page 64070]]

as a WQS pursuant to 40 CFR 131.15 ensures that any NPDES permit that 
contains a compliance schedule meets the requirement that the WQBEL 
derive from and comply with all applicable WQS (40 CFR 
122.44(d)(1)(vii)(A)).
    California is authorized to administer the NPDES program and has 
adopted several mechanisms to authorize compliance schedules in NPDES 
permits. In 2008, California adopted a statewide CSAP that the EPA 
subsequently approved under CWA section 303(c), the Policy for 
Compliance Schedules in National Pollutant Discharge Elimination System 
Permits, SWRCB Resolution No. 2008-0025, April 15, 2008. This EPA-
approved regulation authorizes the use of permit compliance schedules 
consistent with 40 CFR 131.15, and is not affected by this rule. The 
CSAP will allow California, as the permitting authority, to use permit 
compliance schedules, as appropriate, for the purpose of achieving 
compliance with a WQBEL based on a final federal selenium criterion 
that is more stringent than the existing criteria for California, as 
soon as possible.

VII. Economic Analysis

    The proposed criterion would serve as a basis for development of 
new or revised NPDES permit conditions for point source dischargers and 
additional best management practice (BMP) controls on nonpoint sources 
of pollutant loadings. The EPA cannot be certain of whether a 
particular discharger would change their operations if this proposed 
criterion were finalized and the discharger were found to have 
reasonable potential to cause or contribute to an exceedance of a WQS. 
Moreover, the EPA cannot anticipate how California would implement the 
criterion. California is authorized to administer the NPDES program and 
retains discretion in implementing WQS. In addition to examples laid 
out in Section VI--any of which would be consistent with the regulatory 
requirement at 40 CFR 122.44(d)(1)(i) to ensure that State NPDES 
permits comply with the applicable CWA WQS--the State can calculate 
water column criterion elements on a site-specific basis relying on the 
performance-based approach. Despite this discretion, if California 
determines that a permit is necessary, such permit would need to comply 
with the EPA's regulations at 40 CFR 122.44(d)(1)(i). Still, to best 
inform the public of the potential impacts of this proposed rule, the 
EPA made some assumptions to evaluate the potential costs associated 
with State implementation of the EPA's proposed criterion. The EPA 
chose to evaluate the expected costs associated with State 
implementation of the Agency's proposed selenium criterion based on 
available information. This analysis is documented in Economic Analysis 
for Proposed Selenium Water Quality Standards Applicable to the State 
of California, which can be found in the docket for this rulemaking. 
The EPA seeks public comment on all aspects of the economic analysis 
including, but not limited to, its assumptions relating to the baseline 
criteria, affected entities, implementation, and compliance costs.
    For the economic analysis, the EPA assumed the baseline to be full 
implementation of existing water quality criteria (i.e., ``baseline 
criteria'') and then estimated the incremental impacts for compliance 
with the selenium criterion in this proposed rule. Aside from the 
freshwater chronic criterion of 5 [mu]g/L established under the CTR, 
the EPA assumed that the following sites have site-specific criteria: 
The San Joaquin River from Sack Dam to Vernalis, Mud Slough, Salt 
Slough, the constructed and reconstructed water supply channels in the 
Grassland watershed, the surface water tributaries to the Salton Sea, 
and the San Francisco Bay Delta. There are approximately 76 existing 
selenium impairments pursuant to the existing baseline freshwater 
criterion of 5 [mu]g/L. The EPA assumes that the California Regional 
Water Quality Control Boards will develop total maximum daily loads 
(TMDLs) and implementation plans to bring all these waters into 
compliance with baseline criteria. Therefore, any incremental costs 
identified by the economic analysis to comply with the proposed 
criterion above and beyond the baseline are attributable to this 
proposed rule.
    For point source costs, any NPDES-permitted facility that 
discharges selenium could potentially incur compliance costs. The types 
of affected facilities could include industrial facilities and publicly 
owned treatment works (POTWs) discharging wastewater to fresh surface 
waters.
    To facilitate this analysis, the EPA interpreted the proposed 
criterion as the lentic and lotic water-column elements from the 
Agency's 2016 CWA section 304(a) selenium criterion for freshwater, and 
refer to this as the economic analysis criterion. Using the proposed 
performance-based approach detailed in Draft Translation of Selenium 
Tissue Criterion Elements to Site-Specific Water Column Criterion 
Elements for California Version 1, August 8, 2018, site-specific water-
column translations of tissue elements may be more or less stringent 
than the economic analysis criterion for lentic and lotic waters. 
Because the economic analysis criterion reflects the 20th percentile of 
a national set of tissue element translations (see Figure 3.9 on page 
92 of the EPA's 2016 selenium criterion document), the use of these 
values as proxies for the site-specific translations using the 
performance-based approach may be more or less conservative with 
respect to estimating potential associated costs of implementation. 
Hereafter in this section, the term ``economic analysis criterion'' 
refers to the lentic value of 1.5 [mu]g/L and the lotic value of 3.1 
[mu]g/L as proxies for the performance-based approach water-column 
translations of the tissue elements.

A. Identifying Affected Entities

    The EPA estimated costs to municipal, industrial, and other 
dischargers under the proposed criterion. The EPA used its Integrated 
Compliance Information System National Pollutant Discharge Elimination 
System (ICIS-NPDES) database to identify individually permitted 
facilities in California whose NPDES permits contain effluent 
limitations and/or monitoring requirements for selenium. The EPA 
excluded facilities that discharge to saltwater, as well as the 
facilities discharging to waters where SSC are in place for selenium 
(listed above). Based on this review, the EPA identified 110 facilities 
to evaluate for reasonable potential to cause or contribute to an 
exceedance of the applicable proposed criterion (i.e., the lentic or 
lotic water column value applicable based on the receiving water). 
Nineteen facilities demonstrated reasonable potential to exceed the 
applicable proposed criterion that results in the need for water 
quality-based effluent limits that could be lower than current limits. 
Even though the EPA only had sufficient data to analyze 110 facilities 
for reasonable potential to exceed the proposed criterion, the EPA 
identified 249 potentially affected facilities. See the Economic 
Analysis for more details.

B. Method for Estimating Costs

    The EPA estimated costs for point source dischargers that receive 
more stringent limits based on the proposed criterion and existing 
effluent concentrations. The EPA reviewed facility permits, existing 
treatment systems, and available treatment technologies to develop 
likely compliance scenarios and associated incremental costs for each 
permittee to meet their proposed effluent limitations.

[[Page 64071]]

After the EPA costed for the facilities that demonstrated reasonable 
potential to exceed the proposed criterion, it extrapolated those costs 
to the remaining potentially affected facilities, when possible.
    To estimate costs for nonpoint source controls, the EPA compared 
available water quality measurements for selenium against the economic 
analysis criterion to identify lentic and lotic fresh waters that might 
be incrementally impaired under the proposed criterion. Although the 
State of California's implementation procedures may result in different 
waters identified as impaired for selenium and the State may choose a 
different approach to achieving water quality criteria, the EPA 
assumed, for the purpose of its cost analysis, that nonpoint 
dischargers of agricultural drainage return flows to impaired waters in 
regions with a high percentage of irrigated cropland would need to 
implement BMPs to reduce irrigation drainage. To estimate the potential 
incremental impact of the rule on nonpoint sources, the EPA identified 
the incrementally impaired waters with high proportions of cropland. 
The EPA's estimate for incremental BMPs costs included annualized costs 
for implementing drip irrigation to replace a less efficient type of 
irrigation to reduce the return flow from agricultural areas 
surrounding the impaired waters. The EPA also estimated the potential 
administrative costs to government entities to develop TMDLs for the 
potentially impaired waters.

C. Results

    The EPA provides estimated costs to point source dischargers by 
type, based on capital and operation and maintenance costs, reported on 
an annual basis as the sum of annual O&M costs and capital costs 
annualized at a 3% discount rate over the 20-year life of the capital 
equipment. Total costs, if all controls were implemented in the first 
year, range from $34.1 to 50.2 million per year; when reflecting a 5-
year phase-in due to NPDES permit cycle, total costs range from $31.0 
to 45.7 million per year. Deferring some cost to later years reduces 
the total amount and is likely given the 5-year NPDES permit renewal 
cycle and staggered TMDL development.
    The estimated costs to nonpoint sources that may result from state 
implementation of the proposed criterion range from $9.9 to $11.0 
million per year, using a 13-year TMDL phase-in period. The EPA 
annualized BMP capital costs over the expected useful life of the BMPs 
using a 3% discount rate and added annual operation and maintenance 
costs to derive annual cost estimates. See the Economic Analysis for 
more details.
    If there are incrementally impaired waters under the proposed 
criterion, then the California Regional Water Quality Control Boards 
may need to develop TMDLs for these waters, thereby incurring 
incremental government regulatory costs. If there is a separate TMDL 
for each of the 28 incrementally impaired waterbodies, and each TMDL 
costs between $37,000 and $40,000 to complete,\19\ then the cumulative 
costs for doing all of them in a single year may be $1.0 million to 
$1.1 million. Distributing this cost uniformly over 13 years results in 
annual costs of $0.08 to $0.09 million.
---------------------------------------------------------------------------

    \19\ These unit cost estimates derive from values provided in a 
U.S. EPA draft report from 2001, entitled The National Costs of the 
Total Maximum Daily Load Program (EPA 841-D-01-003), escalated to 
$2017. These unit costs per TMDL represent practices from nearly 20 
years ago, and therefore may not reflect increased costs of analysis 
using more sophisticated contemporary methods.
---------------------------------------------------------------------------

    Note that, while this analysis is based on the best publicly 
available data, it may not fully reflect the impact of the proposed 
criterion. If additional monitoring data were available, or if the 
California Regional Water Quality Control Boards increase monitoring of 
ambient conditions in future assessment periods, additional impairments 
may be identified under the baseline and/or proposed criteria. 
Conversely, there may be fewer waters identified as impaired for 
selenium after California has fully implemented baseline activities to 
address sources of existing impairments for selenium or other 
contaminants (e.g., planned baseline BMPs for stormwater discharges 
from urban or industrial sources for metals TMDLs).
    Table 4 shows aggregate costs for point source controls, nonpoint 
source BMPs, and administrative costs for the 3% discount rate, where 
the total annual cost ranges from $41 million to $57 million. The 7% 
discount rate estimates of total annual costs range from $45 million to 
$61 million. See the economic analysis for full derivation.

             Table 4--Summary of Total Annual Cost Estimates
                            [Millions; 2017$]
------------------------------------------------------------------------
                Cost type                    Low cost        High cost
------------------------------------------------------------------------
Point Sources \1\.......................           $31.0           $45.7
Nonpoint Sources \1\....................             9.9            11.0
Government Administration \2\...........            0.04            0.04
                                         -------------------------------
    Total...............................            40.9            56.7
------------------------------------------------------------------------
\1\ Annual costs include capital costs annualized over the 20-year
  expected life of the equipment at 3% plus annual operating and
  maintenance costs. Annual costs also reflect a 5-year implementation
  period for point sources and a 13-year implementation period for
  nonpoint source BMPs.
\2\ Total TMDL development costs are uniformly distributed over 13
  years.

VIII. Statutory and Executive Orders

A. Executive Order 12866 (Regulatory Planning and Review) and Executive 
Order 13563 (Improving Regulation and Regulatory Review)

    As determined by the Office of Management and Budget (OMB), this 
action is a significant regulatory action and was submitted to OMB for 
review. Any changes made during OMB's review have been documented in 
the docket. The EPA evaluated the potential costs to NPDES dischargers 
associated with State implementation of the EPA's proposed criteria. 
This analysis, Economic Analysis for Proposed Selenium Water Quality 
Standards Applicable to the State of California, is summarized in 
Section VII of the preamble and is available in the docket.

B. Executive Order 13771 (Reducing Regulations and Controlling 
Regulatory Costs)

    This action is expected to be an Executive Order 13771 regulatory 
action. Details on the estimated costs of this proposed rule can be 
found in the EPA's analysis of the potential costs and benefits 
associated with this action.

[[Page 64072]]

C. Paperwork Reduction Act (PRA)

    This action does not impose an information collection burden under 
the PRA. While actions to implement these WQS could entail additional 
paperwork burden, this action does not directly contain any information 
collection, reporting, or record-keeping requirements.

D. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. This 
action will not impose any requirements on small entities. The EPA-
promulgated WQS are implemented through various water quality control 
programs including the NPDES program, which limits discharges to 
navigable waters except in compliance with a NPDES permit. CWA Section 
301(b)(1)(C) \20\ and the EPA's implementing regulations at 40 CFR 
122.44(d)(1) and 122.44(d)(1)(A) provide that all NPDES permits shall 
include any limits on discharges that are necessary to meet applicable 
WQS. Thus, under the CWA, the EPA's promulgation of WQS establishes 
standards that the state implements through the NPDES permit process. 
While the state has discretion in developing discharge limits, as 
needed to meet the WQS, those limits, per regulations at 40 CFR 
122.44(d)(1)(i), ``must control all pollutants or pollutant parameters 
(either conventional, nonconventional, or toxic pollutants) which the 
Director determines are or may be discharged at a level that will 
cause, have the reasonable potential to cause, or contribute to an 
excursion above any [s]tate water quality standard, including [s]tate 
narrative criteria for water quality.'' As a result of this action, the 
State of California will need to ensure that permits it issues include 
any limitations on discharges necessary to comply with the WQS 
established in the final rule. In doing so, the State will have a 
number of choices associated with permit writing. While California's 
implementation of the rule may ultimately result in new or revised 
permit conditions for some dischargers, including small entities, the 
EPA's action, by itself, does not impose any of these requirements on 
small entities; that is, these requirements are not self-implementing.
---------------------------------------------------------------------------

    \20\ 301(b) Timetable for Achievement of Objectives. In order to 
carry out the objective of this chapter there shall be achieved--
(1)(C): Not later than July 1, 1977, any more stringent limitation, 
including those necessary to meet water quality standards, treatment 
standards, or schedules of compliance, established pursuant to any 
State law or regulations (under authority preserved by section 1370 
of this title) or any other Federal law or regulation, or required 
to implement any applicable water quality standard established 
pursuant to this chapter.
---------------------------------------------------------------------------

E. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandates as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. As these water quality criteria are not self-
implementing, the action imposes no enforceable duty on any state, 
local or tribal governments or the private sector.

F. Executive Order 13132 (Federalism)

    Under the technical requirements of Executive Order 13132, the EPA 
has determined that this proposed rule may not have federalism 
implications but believes that the consultation requirements of the 
Executive Order have been satisfied in any event. On several occasions 
over the course of February 2018 through September 2018, the EPA 
discussed with the California State Water Quality Control Board and 
several Regional Water Quality Control Boards the Agency's development 
of the federal rulemaking and clarified early in the process that if 
and when the State decided to develop and establish its own selenium 
standards, the EPA would instead assist the State in its process. 
During these discussions, the EPA explained the scientific basis for 
the fish and bird tissue elements of the selenium criterion and the 
methodologies for translating the tissue elements to water column 
values; the external peer review process and the comments the Agency 
received on the derivation of the criterion; the Agency's consideration 
of those comments and responses; possible alternatives for a criteria 
or criterion matrix; and the overall timing of the federal rulemaking 
effort. The EPA coordinated with the State and considered the State's 
initial feedback in making the Agency's decision to propose and solicit 
comment on the criterion matrix and the various options described in 
Section III. Proposed Criterion of this proposed rulemaking.
    The EPA specifically solicits comments on this proposed action from 
state and local officials.

G. Executive Order 13175 (Consultation and Coordination With Indian 
Tribal Governments)

    This action does not have tribal implications as specified in 
Executive Order 13175. This proposed rule does not impose substantial 
direct compliance costs on federally recognized tribal governments, nor 
does it substantially affect the relationship between the federal 
government and tribes, or the distribution of power and 
responsibilities between the federal government and tribes. Thus, 
Executive Order 13175 does not apply to this action.
    Consistent with the EPA Policy on Consultation and Coordination 
with Indian Tribes, the EPA consulted with tribal officials during the 
development of this action. The EPA will continue to communicate with 
the tribes prior to its final action.

H. Executive Order 13045 (Protection of Children From Environmental 
Health and Safety Risks)

    The EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that concern environmental health or safety risks 
that the EPA has reason to believe may disproportionately affect 
children, per the definition of ``covered regulatory action'' in 
section 2-202 of the Executive Order. This action is not subject to 
Executive Order 13045 because it does not concern an environmental 
health risk or safety risk.

I. Executive Order 13211 (Actions That Significantly Affect Energy 
Supply, Distribution, or Use)

    This action is not a ``significant energy action'' because it is 
not likely to have a significant adverse effect on the supply, 
distribution, or use of energy.

J. National Technology Transfer and Advancement Act of 1995

    This proposed rulemaking does not involve technical standards.

K. Executive Order 12898 (Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations)

    The human health or environmental risk addressed by this action 
will not have potential disproportionately high and adverse human 
health or environmental effects on minority, low-income or indigenous 
populations. The criteria in this proposed rule would support the 
health and abundance of aquatic life and aquatic-dependent wildlife in 
California and would, therefore, benefit all communities that rely on 
these ecosystems.

List of Subjects in 40 CFR Part 131

    Environmental protection, Incorporation by reference, Indians--
lands, Intergovernmental relations, Reporting and recordkeeping 
requirements, Water pollution control.

[[Page 64073]]

    Dated: November 29, 2018.
Andrew R. Wheeler,
Acting Administrator.

    For the reasons set forth in the preamble, the EPA proposes to 
amend 40 CFR part 131 as follows:

PART 131--WATER QUALITY STANDARDS

0
1. The authority citation for part 131 continues to read as follows:

    Authority: 33 U.S.C. 1251 et seq.

0
2. Amend Sec.  131.38 by revising the table in paragraph (b)(1) and 
paragraphs (c)(3)(ii) and (iii) to read as follows:

Sec.  131.38   Establishment of numeric criteria for priority toxic 
pollutants for the State of California.

* * * * *
    (b)(1) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                            A                                      B Freshwater                     C Saltwater             D Human health (10-\6\ risk
-------------------------------------------------------------------------------------------------------------------------      for carcinogens) for
                                                                                                                                  consumption of:
                                                             Criterion       Criterion       Criterion       Criterion   -------------------------------
                                                              maximum       continuous        maximum       continuous       Water and
             Number compound                  CAS No.        conc.\d\        conc.\d\        conc.\d\        conc.\d\        organisms    Organisms only
                                                           ([micro]g/L)    ([micro]g/L)    ([micro]g/L)    ([micro]g/L)    ([micro]g/L)    ([micro]g/L)
                                                                B1              B2              C1              C2              D1              D2
--------------------------------------------------------------------------------------------------------------------------------------------------------
1. Antimony.............................         7440360  ..............  ..............  ..............  ..............      \a\ \s\ 14    \a\ \t\ 4300
2. Arsenic \b\..........................         7440382     \i\ \m\ \w\     \i\ \m\ \w\      \i\ \m\ 69      \i\ \m\ 36  ..............  ..............
                                                                     340             150
3. Beryllium............................         7440417  ..............  ..............  ..............  ..............           (\n\)           (\n\)
4. Cadmium \b\..........................         7440439     \e\ \i\ \m\     \e\ \i\ \m\      \i\ \m\ 42     \i\ \m\ 9.3           (\n\)           (\n\)
                                                             \w\ \x\ 4.3         \w\ 2.2
5a. Chromium (III)......................        16065831     \e\ \i\ \m\     \e\ \i\ \m\  ..............  ..............           (\n\)           (\n\)
                                                                 \o\ 550         \o\ 180
5b. Chromium (VI) \b\...................        18540299  \i\ \m\ \w\ 16  \i\ \m\ \w\ 11    \i\ \m\ 1100      \i\ \m\ 50           (\n\)           (\n\)
6. Copper \b\...........................         7440508     \e\ \i\ \m\     \e\ \i\ \m\     \i\ \m\ 4.8     \i\ \m\ 3.1            1300  ..............
                                                              \w\ \x\ 13         \w\ 9.0
7. Lead \b\.............................         7439921     \e\ \i\ \m\     \e\ \i\ \m\     \i\ \m\ 210     \i\ \m\ 8.1           (\n\)           (\n\)
                                                                  \z\ 65         \z\ 2.5
8. Mercury \b\..........................         7439976      [Reserved]      [Reserved]      [Reserved]      [Reserved]       \a\ 0.050       \a\ 0.051
9. Nickel \b\...........................         7440020     \e\ \i\ \m\     \e\ \i\ \m\      \i\ \m\ 74     \i\ \m\ 8.2         \a\ 610        \a\ 4600
                                                                 \w\ 470          \w\ 52
10. Selenium \b\........................         7782492           (\p\)      (\q\ \aa\)     \i\ \m\ 290      \i\ \m\ 71           (\n\)           (\n\)
11. Silver \b\..........................         7440224     \e\ \i\ \m\  ..............     \i\ \m\ 1.9  ..............  ..............  ..............
                                                                     3.4
12. Thallium............................         7440280  ..............  ..............  ..............  ..............     \a\ \s\ 1.7     \a\ \t\ 6.3
13. Zinc \b\............................         7440666     \e\ \i\ \m\     \e\ \i\ \m\      \i\ \m\ 90      \i\ \m\ 81  ..............  ..............
                                                             \w\ \x\ 120         \w\ 120
14. Cyanide \b\.........................           57125          \o\ 22         \o\ 5.2           \r\ 1           \r\ 1         \a\ 700         \a\ \j\
                                                                                                                                                 220,000
15. Asbestos............................         1332214  ..............  ..............  ..............  ..............         \k\ \s\  ..............
                                                                                                                               7,000,000
                                                                                                                                fibers/L
16. 2,3,7,8-TCDD (Dioxin)...............         1746016  ..............  ..............  ..............  ..............             \c\             \c\
                                                                                                                             0.000000013     0.000000014
17. Acrolein............................          107028  ..............  ..............  ..............  ..............         \s\ 320         \t\ 780
18. Acrylonitrile.......................          107131  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                   0.059            0.66
19. Benzene.............................           71432  ..............  ..............  ..............  ..............     \a\ \c\ 1.2      \a\ \c\ 71
20. Bromoform...........................           75252  ..............  ..............  ..............  ..............     \a\ \c\ 4.3     \a\ \c\ 360
21. Carbon Tetrachloride................           56235  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                    0.25             4.4
22. Chlorobenzene.......................          108907  ..............  ..............  ..............  ..............     \a\ \s\ 680     \a\ \j\ \t\
                                                                                                                                                  21,000
23. Chlorodibromomethane................          124481  ..............  ..............  ..............  ..............     \a\ \c\ \y\      \a\ \c\ 34
                                                                                                                                    0.41
24. Chloroethane........................           75003  ..............  ..............  ..............  ..............  ..............  ..............
25. 2-Chloroethylvinyl Ether............          110758  ..............  ..............  ..............  ..............  ..............  ..............
26. Chloroform..........................           67663  ..............  ..............  ..............  ..............      [Reserved]      [Reserved]
27. Dichlorobromomethane................           75274  ..............  ..............  ..............  ..............     \a\ \c\ \y\      \a\ \c\ 46
                                                                                                                                    0.56
28. 1,1-Dichloroethane..................           75343  ..............  ..............  ..............  ..............  ..............  ..............
29. 1,2-Dichloroethane..................          107062  ..............  ..............  ..............  ..............     \a\ \c\ \s\  \a\ \c\ \t\ 99
                                                                                                                                    0.38
30. 1,1-Dichloroethylene................           75354  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                   0.057             3.2
31. 1,2-Dichloropropane.................           78875  ..............  ..............  ..............  ..............        \a\ 0.52          \a\ 39
32. 1,3-Dichloropropylene...............          542756  ..............  ..............  ..............  ..............      \a\ \s\ 10   \a\ \t\ 1,700
33. Ethylbenzene........................          100414  ..............  ..............  ..............  ..............   \a\ \s\ 3,100  \a\ \t\ 29,000
34. Methyl Bromide......................           74839  ..............  ..............  ..............  ..............          \a\ 48       \a\ 4,000
35. Methyl Chloride.....................           74873  ..............  ..............  ..............  ..............           (\n\)           (\n\)
36. Methylene Chloride..................           75092  ..............  ..............  ..............  ..............     \a\ \c\ 4.7   \a\ \c\ 1,600
37. 1,1,2,2-Tetrachloroethane...........           79345  ..............  ..............  ..............  ..............     \a\ \c\ \s\  \a\ \c\ \t\ 11
                                                                                                                                    0.17
38. Tetrachloroethylene.................          127184  ..............  ..............  ..............  ..............     \c\ \s\ 0.8    \c\ \t\ 8.85
39. Toluene.............................          108883  ..............  ..............  ..............  ..............       \a\ 6,800     \a\ 200,000
40. 1,2-Trans-Dichloroethylene..........          156605  ..............  ..............  ..............  ..............         \a\ 700     \a\ 140,000
41. 1,1,1-Trichloroethane...............           71556  ..............  ..............  ..............  ..............           (\n\)           (\n\)
42. 1,1,2-Trichloroethane...............           79005  ..............  ..............  ..............  ..............     \a\ \c\ \s\  \a\ \c\ \t\ 42
                                                                                                                                    0.60

[[Page 64074]]

 
43. Trichloroethylene...................           79016  ..............  ..............  ..............  ..............     \c\ \s\ 2.7      \c\ \t\ 81
44. Vinyl Chloride......................           75014  ..............  ..............  ..............  ..............       \c\ \s\ 2     \c\ \t\ 525
45. 2-Chlorophenol......................           95578  ..............  ..............  ..............  ..............         \a\ 120         \a\ 400
46. 2,4-Dichlorophenol..................          120832  ..............  ..............  ..............  ..............      \a\ \s\ 93     \a\ \t\ 790
47. 2,4-Dimethylphenol..................          105679  ..............  ..............  ..............  ..............         \a\ 540       \a\ 2,300
48. 2-Methyl-4,6-Dinitrophenol..........          534521  ..............  ..............  ..............  ..............        \s\ 13.4         \t\ 765
49. 2,4-Dinitrophenol...................           51285  ..............  ..............  ..............  ..............      \a\ \s\ 70  \a\ \t\ 14,000
50. 2-Nitrophenol.......................           88755  ..............  ..............  ..............  ..............  ..............  ..............
51. 4-Nitrophenol.......................          100027  ..............  ..............  ..............  ..............  ..............  ..............
52. 3-Methyl-4-Chlorophenol.............           59507  ..............  ..............  ..............  ..............  ..............  ..............
53. Pentachlorophenol...................           87865      \f\ \w\ 19      \f\ \w\ 15              13             7.9    \a\ \c\ 0.28     \a\ \c\ \j\
                                                                                                                                                     8.2
54. Phenol..............................          108952  ..............  ..............  ..............  ..............      \a\ 21,000     \a\ \j\ \t\
                                                                                                                                               4,600,000
55. 2,4,6-Trichlorophenol...............           88062  ..............  ..............  ..............  ..............     \a\ \c\ 2.1     \a\ \c\ 6.5
56. Acenaphthene........................           83329  ..............  ..............  ..............  ..............       \a\ 1,200       \a\ 2,700
57. Acenaphthylene......................          208968  ..............  ..............  ..............  ..............  ..............  ..............
58. Anthracene..........................          120127  ..............  ..............  ..............  ..............       \a\ 9,600     \a\ 110,000
59. Benzidine...........................           92875  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                 0.00012         0.00054
60. Benzo(a)Anthracene..................           56553  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
61. Benzo(a)Pyrene......................           50328  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
62. Benzo(b)Fluoranthene................          205992  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
63. Benzo(ghi)Perylene..................          191242  ..............  ..............  ..............  ..............  ..............  ..............
64. Benzo(k)Fluoranthene................          207089  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
65. Bis(2-Chloroethoxy)Methane..........          111911  ..............  ..............  ..............  ..............  ..............  ..............
66. Bis(2-Chloroethyl)Ether.............          111444  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                   0.031             1.4
67. Bis(2-Chloroisopropyl)Ether.........          108601  ..............  ..............  ..............  ..............       \a\ 1,400         \a\ \t\
                                                                                                                                                 170,000
68. Bis(2-Ethylhexyl)Phthalate..........          117817  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                     1.8             5.9
69. 4-Bromophenyl Phenyl Ether..........          101553  ..............  ..............  ..............  ..............  ..............  ..............
70. Butylbenzyl Phthalate...............           85687  ..............  ..............  ..............  ..............       \a\ 3,000       \a\ 5,200
71. 2-Chloronaphthalene.................           91587  ..............  ..............  ..............  ..............       \a\ 1,700       \a\ 4,300
72. 4-Chlorophenyl Phenyl Ether.........         7005723  ..............  ..............  ..............  ..............  ..............  ..............
73. Chrysene............................          218019  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
74. Dibenzo(a,h)Anthracene..............           53703  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
75. 1,2 Dichlorobenzene.................           95501  ..............  ..............  ..............  ..............       \a\ 2,700      \a\ 17,000
76. 1,3 Dichlorobenzene.................          541731  ..............  ..............  ..............  ..............             400           2,600
77. 1,4 Dichlorobenzene.................          106467  ..............  ..............  ..............  ..............             400           2,600
78. 3,3'-Dichlorobenzidine..............           91941  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                    0.04           0.077
79. Diethyl Phthalate...................           84662  ..............  ..............  ..............  ..............  \a\ \s\ 23,000         \a\ \t\
                                                                                                                                                 120,000
80. Dimethyl Phthalate..................          131113  ..............  ..............  ..............  ..............     \s\ 313,000   \t\ 2,900,000
81. Di-n-Butyl Phthalate................           84742  ..............  ..............  ..............  ..............   \a\ \s\ 2,700  \a\ \t\ 12,000
82. 2,4-Dinitrotoluene..................          121142  ..............  ..............  ..............  ..............    \c\ \s\ 0.11     \c\ \t\ 9.1
83. 2,6-Dinitrotoluene..................          606202  ..............  ..............  ..............  ..............  ..............  ..............
84. Di-n-Octyl Phthalate................          117840  ..............  ..............  ..............  ..............  ..............  ..............
85. 1,2-Diphenylhydrazine...............          122667  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                   0.040            0.54
86. Fluoranthene........................          206440  ..............  ..............  ..............  ..............         \a\ 300         \a\ 370
87. Fluorene............................           86737  ..............  ..............  ..............  ..............       \a\ 1,300      \a\ 14,000

[[Page 64075]]

 
88. Hexachlorobenzene...................          118741  ..............  ..............  ..............  ..............         \a\ \c\         \a\ \c\
                                                                                                                                 0.00075         0.00077
89. Hexachlorobutadiene.................           87683  ..............  ..............  ..............  ..............     \a\ \c\ \s\  \a\ \c\ \t\ 50
                                                                                                                                    0.44
90. Hexachlorocyclopentadiene...........           77474  ..............  ..............  ..............  ..............     \a\ \s\ 240     \a\ \j\ \t\
                                                                                                                                                  17,000
91. Hexachloroethane....................           67721  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                     1.9             8.9
92. Indeno(1,2,3-cd) Pyrene.............          193395  ..............  ..............  ..............  ..............  \a\ \c\ 0.0044   \a\ \c\ 0.049
93. Isophorone..........................           78591  ..............  ..............  ..............  ..............     \c\ \s\ 8.4     \c\ \t\ 600
94. Naphthalene.........................           91203  ..............  ..............  ..............  ..............  ..............  ..............
95. Nitrobenzene........................           98953  ..............  ..............  ..............  ..............      \a\ \s\ 17     \a\ \j\ \t\
                                                                                                                                                   1,900
96. N-Nitrosodimethylamine..............           62759  ..............  ..............  ..............  ..............     \a\ \c\ \s\     \a\ \c\ \t\
                                                                                                                                 0.00069             8.1
97. N-Nitrosodi-n-Propylamine...........          621647  ..............  ..............  ..............  ..............       \a\ 0.005         \a\ 1.4
98. N-Nitrosodiphenylamine..............           86306  ..............  ..............  ..............  ..............     \a\ \c\ \s\  \a\ \c\ \t\ 16
                                                                                                                                     5.0
99. Phenanthrene........................           85018  ..............  ..............  ..............  ..............  ..............  ..............
100. Pyrene.............................          129000  ..............  ..............  ..............  ..............         \a\ 960      \a\ 11,000
101. 1,2,4-Trichlorobenzene.............          120821  ..............  ..............  ..............  ..............  ..............  ..............
102. Aldrin.............................          309002           \g\ 3  ..............         \g\ 1.3  ..............         \a\ \c\         \a\ \c\
                                                                                                                                 0.00013         0.00014
103. alpha-BHC..........................          319846  ..............  ..............  ..............  ..............  \a\ \c\ 0.0039   \a\ \c\ 0.013
104. beta-BHC...........................          319857  ..............  ..............  ..............  ..............   \a\ \c\ 0.014   \a\ \c\ 0.046
105. gamma-BHC..........................           58899        \w\ 0.95  ..............        \g\ 0.16  ..............       \c\ 0.019       \c\ 0.063
106. delta-BHC..........................          319868  ..............  ..............  ..............  ..............  ..............  ..............
107. Chlordane..........................           57749         \g\ 2.4      \g\ 0.0043        \g\ 0.09       \g\ 0.004         \a\ \c\         \a\ \c\
                                                                                                                                 0.00057         0.00059
108. 4,4'-DDT...........................           50293         \g\ 1.1       \g\ 0.001        \g\ 0.13       \g\ 0.001         \a\ \c\         \a\ \c\
                                                                                                                                 0.00059         0.00059
109. 4,4'-DDE...........................           72559  ..............  ..............  ..............  ..............         \a\ \c\         \a\ \c\
                                                                                                                                 0.00059         0.00059
110. 4,4'-DDD...........................           72548  ..............  ..............  ..............  ..............         \a\ \c\         \a\ \c\
                                                                                                                                 0.00083         0.00084
111. Dieldrin...........................           60571        \w\ 0.24       \w\ 0.056        \g\ 0.71      \g\ 0.0019         \a\ \c\         \a\ \c\
                                                                                                                                 0.00014         0.00014
112. alpha-Endosulfan...................          959988        \g\ 0.22       \g\ 0.056       \g\ 0.034      \g\ 0.0087         \a\ 110         \a\ 240
113. beta-Endosulfan....................        33213659        \g\ 0.22       \g\ 0.056       \g\ 0.034      \g\ 0.0087         \a\ 110         \a\ 240
114. Endosulfan Sulfate.................         1031078  ..............  ..............  ..............  ..............         \a\ 110         \a\ 240
115. Endrin.............................           72208       \w\ 0.086       \w\ 0.036       \g\ 0.037      \g\ 0.0023        \a\ 0.76    \a\ \j\ 0.81
116. Endrin Aldehyde....................         7421934  ..............  ..............  ..............  ..............        \a\ 0.76    \a\ \j\ 0.81
117. Heptachlor.........................           76448        \g\ 0.52      \g\ 0.0038       \g\ 0.053      \g\ 0.0036         \a\ \c\         \a\ \c\
                                                                                                                                 0.00021         0.00021
118. Heptachlor Epoxide.................         1024573        \g\ 0.52      \g\ 0.0038       \g\ 0.053      \g\ 0.0036         \a\ \c\         \a\ \c\
                                                                                                                                 0.00010         0.00011
119-125. Polychlorinated biphenyls        ..............  ..............       \u\ 0.014  ..............        \u\ 0.03         \c\ \v\         \c\ \v\
 (PCBs).................................                                                                                         0.00017         0.00017
126. Toxaphene..........................         8001352            0.73          0.0002            0.21          0.0002         \a\ \c\         \a\ \c\
                                                                                                                                 0.00073         0.00075
                                         ---------------------------------------------------------------------------------------------------------------
    Total Number of Criteria \h\........  ..............              22              21              22              20              92              90
--------------------------------------------------------------------------------------------------------------------------------------------------------
Footnotes to Table In Paragraph (b)(1):
\a\ Criteria revised to reflect the Agency q1* or RfD, as contained in the Integrated Risk Information System (IRIS) as of October 1, 1996. The fish
  tissue bioconcentration factor (BCF) from the 1980 documents was retained in each case.
\b\ Criteria apply to California waters except for those waters subject to objectives in Tables III-2A and III-2B of the San Francisco Regional Water
  Quality Control Board's (SFRWQCB) 1986 Basin Plan that were adopted by the SFRWQCB and the State Water Resources Control Board, approved by the EPA,
  and which continue to apply. For copper and nickel, criteria apply to California waters except for waters south of Dumbarton Bridge in San Francisco
  Bay that are subject to the objectives in the SFRWQCB's Basin Plan as amended by SFRWQCB Resolution R2-2002-0061, dated May 22, 2002, and approved by
  the State Water Resources Control Board. The EPA approved the aquatic life site-specific objectives on January 21, 2003. The copper and nickel aquatic
  life site-specific objectives contained in the amended Basin Plan apply instead.
\c\ Criteria are based on carcinogenicity of 10 (-6) risk.
\d\ Criteria Maximum Concentration (CMC) equals the highest concentration of a pollutant to which aquatic life can be exposed for a short period of time
  without deleterious effects. Criteria Continuous Concentration (CCC) equals the highest concentration of a pollutant to which aquatic life can be
  exposed for an extended period of time (4 days) without deleterious effects. ug/L equals micrograms per liter.
\e\ Freshwater aquatic life criteria for metals are expressed as a function of total hardness (mg/L) in the water body. The equations are provided in
  matrix at paragraph (b)(2) of this section. Values displayed above in the matrix correspond to a total hardness of 100 mg/l.
\f\ Freshwater aquatic life criteria for pentachlorophenol are expressed as a function of pH, and are calculated as follows: Values displayed above in
  the matrix correspond to a pH of 7.8. CMC = exp(1.005(pH)-4.869). CCC = exp(1.005(pH)-5.134).

[[Page 64076]]

 
\g\ This criterion is based on 304(a) aquatic life criterion issued in 1980, and was issued in one of the following documents: Aldrin/Dieldrin (EPA 440/
  5-80-019), Chlordane (EPA 440/5-80-027), DDT (EPA 440/5-80-038), Endosulfan (EPA 440/5-80-046), Endrin (EPA 440/5-80-047), Heptachlor (440/5-80-052),
  Hexachlorocyclohexane (EPA 440/5-80-054), Silver (EPA 440/5-80-071). The Minimum Data Requirements and derivation procedures were different in the
  1980 Guidelines than in the 1985 Guidelines. For example, a ``CMC'' derived using the 1980 Guidelines was derived to be used as an instantaneous
  maximum. If assessment is to be done using an averaging period, the values given should be divided by 2 to obtain a value that is more comparable to a
  CMC derived using the 1985 Guidelines.
\h\ These totals simply sum the criteria in each column. For aquatic life, there are 23 priority toxic pollutants with some type of freshwater or
  saltwater, acute or chronic criteria. For human health, there are 92 priority toxic pollutants with either ``water + organism'' or ``organism only''
  criteria. Note that these totals count chromium as one pollutant even though the EPA has developed criteria based on two valence states. In the
  matrix, the EPA has assigned numbers 5a and 5b to the criteria for chromium to reflect the fact that the list of 126 priority pollutants includes only
  a single listing for chromium.
\i\ Criteria for these metals are expressed as a function of the water-effect ratio, WER, as defined in paragraph (c) of this section. CMC = column B1
  or C1 value x WER; CCC = column B2 or C2 value x WER.
\j\ No criterion for protection of human health from consumption of aquatic organisms (excluding water) was presented in the 1980 criteria document or
  in the 1986 Quality Criteria for Water. Nevertheless, sufficient information was presented in the 1980 document to allow a calculation of a criterion,
  even though the results of such a calculation were not shown in the document.
\k\ The CWA 304(a) criterion for asbestos is the MCL.
\l\ [Reserved].
\m\ These freshwater and saltwater criteria for metals are expressed in terms of the dissolved fraction of the metal in the water column. Criterion
  values were calculated by using the EPA's Clean Water Act 304(a) guidance values (described in the total recoverable fraction) and then applying the
  conversion factors in Sec.   131.36(b)(1) and (2).
\n\ The EPA is not promulgating human health criteria for these contaminants. However, permit authorities should address these contaminants in NPDES
  permit actions using the State's existing narrative criteria for toxics.
\o\ These criteria were promulgated for specific waters in California in the National Toxics Rule (``NTR''), at Sec.   131.36. The specific waters to
  which the NTR criteria apply include: Waters of the State defined as bays or estuaries and waters of the State defined as inland, i.e., all surface
  waters of the State not ocean waters. These waters specifically include the San Francisco Bay upstream to and including Suisun Bay and the Sacramento-
  San Joaquin Delta. This section does not apply instead of the NTR for this criterion.
\p\ No acute criterion applies except as follows. A criterion of 20 [micro]g/L was promulgated for specific waters in California in the NTR in the total
  recoverable form and still applies to waters of the San Francisco Bay upstream to and including Suisun Bay and the Sacramento-San Joaquin Delta;
  waters of Salt Slough; Mud Slough (north); and the San Joaquin River, Sack Dam to the mouth of Merced River. The State of California adopted and the
  EPA approved site-specific acute criteria that still apply to the San Joaquin River, mouth of Merced to Vernalis; Salt Slough; constructed and
  reconstructed water supply channels in the Grassland watershed listed in Appendix 40 of the State of California Central Valley Regional Water Quality
  Control Board Basin Plan; and all surface waters that are tributaries to the Salton Sea.
\q\ The chronic criterion specified in footnote aa applies except as follows. A chronic criterion of 5 [micro]g/L was promulgated for specific waters in
  California in the NTR in the total recoverable form and still applies to waters of the San Francisco Bay upstream to and including Suisun Bay and the
  Sacramento-San Joaquin Delta; waters of Salt Slough; Mud Slough (north); and the San Joaquin River, Sack Dam to Vernalis. Footnote aa does not apply
  instead of the NTR for these waters. The State of California adopted and the EPA approved a site-specific criterion for the Salt Slough, constructed
  and reconstructed water supply channels in the Grassland watershed listed in appendix 40 of the State of California Central Valley Regional Water
  Quality Control Board Basin Plan, and all surface waters that are tributaries to the Salton Sea; therefore, footnote aa does not apply to these
  waters.
\r\ These criteria were promulgated for specific waters in California in the NTR. The specific waters to which the NTR criteria apply include: Waters of
  the State defined as bays or estuaries including the Sacramento-San Joaquin Delta within California Regional Water Board 5, but excluding the San
  Francisco Bay. This section does not apply instead of the NTR for these criteria.
\s\ These criteria were promulgated for specific waters in California in the NTR. The specific waters to which the NTR criteria apply include: Waters of
  the Sacramento-San Joaquin Delta and waters of the State defined as inland (i.e., all surface waters of the State not bays or estuaries or ocean) that
  include a MUN use designation. This section does not apply instead of the NTR for these criteria.
\t\ These criteria were promulgated for specific waters in California in the NTR. The specific waters to which the NTR criteria apply include: Waters of
  the State defined as bays and estuaries including San Francisco Bay upstream to and including Suisun Bay and the Sacramento-San Joaquin Delta; and
  waters of the State defined as inland (i.e., all surface waters of the State not bays or estuaries or ocean) without a MUN use designation. This
  section does not apply instead of the NTR for these criteria.
\u\ PCBs are a class of chemicals which include aroclors 1242, 1254, 1221, 1232, 1248, 1260, and 1016, CAS numbers 53469219, 11097691, 11104282,
  11141165, 12672296, 11096825, and 12674112, respectively. The aquatic life criteria apply to the sum of this set of seven aroclors.
\v\ This criterion applies to total PCBs, e.g., the sum of all congener or isomer or homolog or aroclor analyses.
\w\ This criterion has been recalculated pursuant to the 1995 Updates: Water Quality Criteria Documents for the Protection of Aquatic Life in Ambient
  Water, Office of Water, EPA-820-B-96-001, September 1996. See also Great Lakes Water Quality Initiative Criteria Documents for the Protection of
  Aquatic Life in Ambient Water, Office of Water, EPA-80-B-95-004, March 1995.
\x\ The State of California has adopted and the EPA has approved site specific criteria for the Sacramento River (and tributaries) above Hamilton City;
  therefore, these criteria do not apply to these waters.
\y\ The State of California adopted and the EPA approved a site-specific criterion for New Alamo Creek from Old Alamo Creek to Ulatis Creek and for
  Ulatis Creek from Alamo Creek to Cache Slough; therefore, this criterion does not apply to these waters.
\z\ The State of California adopted and the EPA approved a site-specific criterion for the Los Angeles River and its tributaries; therefore, this
  criterion does not apply to these waters.
aa Proposed California Freshwater Selenium Ambient Chronic Water Quality Criterion for Protection of Aquatic Life and Aquatic-Dependent Wildlife

[[Page 64077]]

[GRAPHIC] [TIFF OMITTED] TP13DE18.008

General Notes to Table in Paragraph (b)(1)

    1. The table in this paragraph (b)(1) lists all of the EPA's 
priority toxic pollutants whether or not criteria guidance are 
available. Blank spaces indicate the absence of national section 304(a) 
criteria guidance. Because of variations in chemical nomenclature 
systems, this listing of toxic pollutants does not duplicate the 
listing in appendix A to 40 CFR part 423-126 Priority Pollutants. The 
EPA has added the Chemical Abstracts Service (CAS) registry numbers, 
which provide a unique identification for each chemical.
    2. The following chemicals have organoleptic-based criteria 
recommendations that are not included on this chart: Zinc, 3-methyl-4-
chlorophenol.
    3. Freshwater and saltwater aquatic life criteria apply as 
specified in paragraph (c)(3) of this section.
* * * * *
    (c) * * *
    (3) * * *
    (ii) For waters in which the salinity is equal to or greater than 
10 parts per

[[Page 64078]]

thousand 95% or more of the time, the applicable criteria are the 
saltwater criteria in Column C, except for selenium in waters of the 
San Francisco Bay upstream to and including Suisun Bay and the 
Sacramento-San Joaquin Delta where the applicable criteria are the 
freshwater criteria in Column B of the National Toxic Rule (``NTR'') at 
Sec.  131.36.
    (iii) For waters in which the salinity is between 1 and 10 parts 
per thousand as defined in paragraphs (c)(3)(i) and (ii) of this 
section, the applicable criteria are the more stringent of the 
freshwater or saltwater criteria, except for selenium in waters of the 
San Francisco Bay upstream to and including Suisun Bay and the 
Sacramento-San Joaquin Delta where the applicable criteria are the 
freshwater criteria in Column B of the NTR. However, the Regional 
Administrator may approve the use of the alternative freshwater or 
saltwater criteria if scientifically defensible information and data 
demonstrate that on a site-specific basis the biology of the water body 
is dominated by freshwater aquatic life and that freshwater criteria 
are more appropriate; or conversely, the biology of the water body is 
dominated by saltwater aquatic life and that saltwater criteria are 
more appropriate. Before approving any change, the EPA will publish for 
public comment a document proposing the change.
* * * * *
[FR Doc. 2018-26781 Filed 12-12-18; 8:45 am]
 BILLING CODE 6560-50-P