[Federal Register Volume 83, Number 239 (Thursday, December 13, 2018)]
[Proposed Rules]
[Pages 64059-64078]
[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<PHONE_NUMBER> 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<PHONE_NUMBER>.
    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:<PHONE_NUMBER>; email address:
<EMAIL_ADDRESS>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<EMAIL_ADDRESS>
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

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

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

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

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,

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.
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    \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

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

[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.

    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

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

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)

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.

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.

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.

    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

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

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\