[Federal Register Volume 74, Number 249 (Wednesday, December 30, 2009)]
[Notices]
[Pages 69086-69087]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-30992]
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ENVIRONMENTAL PROTECTION AGENCY
[FRL-9097-8; OW-2009-0921]
Draft 2009 Update Aquatic Life Ambient Water Quality Criteria for
Ammonia--Freshwater
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of availability of draft criteria and request for
scientific views.
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SUMMARY: Pursuant to section 304(a) of the Clean Water Act (CWA), the
Environmental Protection Agency (EPA) is announcing the availability of
draft national recommended water quality criteria for ammonia for the
protection of aquatic life. The draft criteria are based on EPA's
Guidelines for Deriving Numerical National Water Quality Criteria for
the Protection of Aquatic Organisms and Their Uses (1985), (EPA/R-85-
100). EPA's recommended section 304(a) water quality criteria provide
guidance to States and authorized tribes in adopting water quality
standards for protecting aquatic life and human health and provide
guidance to EPA for promulgating Federal regulations under CWA section
303(c), when such action is necessary.
DATES: Scientific views must be received on or before March 1, 2010.
Comments postmarked after this date may not be considered.
ADDRESSES: Submit your scientific views, identified by Docket ID No.
EPA-HQ-OW-2009- 0921, by one of the following methods:
http://www.regulations.gov: Follow the on-line
instructions for submitting comments.
E-mail: [email protected].
Mail: U.S. Environmental Protection Agency; EPA Docket
Center (EPA/DC) Water Docket, MC 28221T; 1200 Pennsylvania Avenue, NW.,
Washington, DC 20460.
Hand Delivery: EPA Docket Center, 1301 Constitution Ave,
NW., EPA West, Room 3334, Washington DC. Such deliveries are only
accepted during the Docket's normal hours of operation, and special
arrangements should be made for deliveries of boxed information.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OW-2009-
0921. EPA's policy is that all comments received will be included in
the public docket without change and may be made available online at
http://www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through http://www.regulations.gov or e-mail. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an e-mail comment directly to EPA without
going through http://www.regulations.gov your e-mail address will be
automatically captured and included as part of the comment that is
placed in the public docket and made available on the Internet. If you
submit an electronic comment, EPA recommends that you include your name
and other contact information in the body of your comment and with any
disk or CD-ROM you submit. If EPA cannot read your comment due to
technical difficulties and cannot contact you for clarification, EPA
may not be able to consider your comment. Electronic files should avoid
the use of special characters, any form of encryption, and be free of
any defects or viruses. For additional information about EPA's public
docket visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
Docket: All documents in the docket are listed in the http://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 http://www.regulations.gov or in hard copy at the Office of Water
Docket/EPA/DC, 1301 Constitution Ave, NW., EPA West, Room 3334,
Washington DC. This Docket Facility is open from 8:30 a.m. until 4:30
p.m., EST, Monday through Friday, excluding legal holidays. The
telephone number for the Public Reading Room is (202) 566-1744, and the
telephone number for the Office of Water Docket is (202) 566-2426.
FOR FURTHER INFORMATION CONTACT: Lisa Huff, Health and Ecological
Criteria Division (4304T), U.S. EPA, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460; (202) 566-0787; [email protected].
SUPPLEMENTARY INFORMATION:
I. What Are Water Quality Criteria?
Water quality criteria are either narrative descriptions of water
quality or scientifically derived numeric values that protect aquatic
life or human health from the deleterious effects of pollutants in
ambient water.
Section 304(a)(1) of the Clean Water Act requires EPA to develop
and publish and, from time to time, revise, criteria for water quality
accurately reflecting the latest scientific knowledge. Water quality
criteria developed under section 304(a) are based solely on data and
scientific judgments on the relationship between pollutant
concentrations and environmental and human health effects. Section
304(a) criteria do not reflect consideration of economic impacts or the
technological feasibility of meeting pollutant concentrations in
ambient water.
Section 304(a) criteria provide guidance to States and authorized
tribes in adopting water quality standards that ultimately provide a
basis for controlling discharges or releases of pollutants. The
criteria also provide guidance to EPA when promulgating Federal
regulations under section 303(c) when such action is necessary. Under
the CWA and its implementing regulations, States and authorized tribes
are to adopt water quality criteria to protect designated uses (e.g.,
public water supply, aquatic life, recreational use, or industrial
use). EPA's recommended water quality criteria do not substitute for
the CWA or regulations, nor are they regulations themselves. Thus,
EPA's recommended criteria do not impose legally binding requirements.
States and authorized tribes have the discretion to adopt, where
appropriate, other scientifically
[[Page 69087]]
defensible water quality criteria that differ from these
recommendations.
II. What Are the Ammonia Criteria?
EPA is today publishing draft national recommended water quality
criteria (NRWQC) for ammonia for protecting aquatic life. These draft
criteria updates are based on EPA's Guidelines for Deriving Numerical
National Water Quality Criteria for the Protection of Aquatic Organisms
and Their Uses (1985), (EPA/R-85-100). These Guidelines describe the
Agency's current approach for deriving national recommended water
quality criteria to protect aquatic life. Toxicity data and other
information on the effects of ammonia were obtained from reliable
sources and subjected to both internal and external scientific peer
review. The NRWQC for ammonia saltwater are not being updated at this
time.
Freshwater: Freshwater aquatic organisms and their uses should not
be affected unacceptably if--
1. The one-hour average concentration of total ammonia nitrogen (in
mg N/L) does not exceed, more than once every three years on the
average, the CMC (acute criterion), which is dependent on the aquatic
organisms present.
2A. The thirty-day average concentration of total ammonia nitrogen
(in mg N/L) does not exceed, more than once every three years on the
average, the CCC (chronic criterion), which is dependent on the aquatic
organisms present.
2B. In addition, the highest four-day average within the 30-day
period should not exceed 2.5 times the CCC.
The acute and chronic criteria concentrations are expressed as
functions of temperature and pH, such that values differ across sites,
and differ over time within a site. See draft criteria document (pp.
34-38) for actual equations describing this function. As temperature
decreases, invertebrates, but not fish, become less sensitive to
ammonia, and below a particular temperature threshold, fish become the
most sensitive genera.
Acute Criteria: At pH=8, where freshwater mussels are present, the
criterion concentration ranges from 1.90 mg N/L at 30[deg] C to 9.81 mg
N/L at 0[deg] C. At pH=8, where freshwater mussels are absent the
criterion concentration ranges from 3.29 mg N/L at 30[deg] C to 9.99 mg
N/L at 0[deg] C.
Chronic Criteria: At pH=8, where freshwater mussels are present,
irrespective of whether fish early life stages (ELS) are present or
absent, the criterion ranges from 0.186 mg N/L at 30[deg] C to 0.817 mg
N/L at 0[deg] C. When freshwater mussels are absent, the values range
from 1.33 mg N/L at 30[deg] C to 2.32 mg N/L at 0[deg] C at times when
fish ELS are present, and from 1.33 mg N/L at 30[deg] C to 5.87 mg N/L
at 0[deg] C at times when fish ELS are absent.
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Draft 2009 ammonia Current 1999
criteria (at pH 8 criteria (at pH 8
and 25[deg] C) and 25[deg] C)
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Acute......................... 2.9 mg N/L mussels 5.6 mg N/L salmon
present. present.
5.0 mg N/L mussels
absent.
Chronic....................... 0.26 mg N/L mussels 1.2 mg N/L fish
present. early life stages
present.
1.8 mg N/L mussels
absent.
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Note: These criteria values are appropriate at the standard
normalized pH and temperature; the criteria values are a function of
the variability of pH and temperature.
The water quality criteria for ammonia saltwater are not being
updated at this time.
III. What is the Relationship Between the Water Quality Criteria and
State or Tribal Water Quality Standards?
As part of the water quality standards triennial review process
defined in Section 303(c)(1) of the CWA, the States and authorized
Tribes are responsible for maintaining and revising water quality
standards. Water quality standards consist of three principal elements:
designated uses, water quality criteria to protect those uses, and
antidegradation requirements, providing for protection of existing
water uses and limitations on degradation of high quality waters.
Section 303(c)(1) requires States and authorized Tribes to review and
modify, if appropriate, their water quality standards at least once
every three years.
States and authorized Tribes must adopt water quality criteria that
protect designated uses. States may develop their criteria based on
EPA's recommended section 304(a) water quality criteria or other
scientifically defensible methods. A State's criteria must contain
sufficient parameters or constituents to protect the designated uses.
Consistent with 40 CFR 131.21, new or revised water quality criteria
adopted into law by States and authorized Tribes on or after May 30,
2000 are in effect for CWA purposes only after EPA approval.
IV. Where Can I Find More Information About Water Quality Criteria and
Water Quality Standards?
For more information about water quality criteria and Water Quality
Standards refer to the following: Water Quality Standards Handbook (EPA
823-B94-005a); Advanced Notice of Proposed Rule Making (ANPRM),
(63FR36742); Water Quality Criteria and Standards Plan--Priorities for
the Future (EPA 822-R-98-003); Guidelines and Methodologies Used in the
Preparation of Health Effects Assessment Chapters of the Consent Decree
Water Criteria Documents (45FR79347); Methodology for Deriving Ambient
Water Quality Criteria for the Protection of Human Health (2000), EPA-
822-B-00-004); Guidelines for Deriving Numerical National Water Quality
Criteria for the Protection of Aquatic Organisms and Their Uses (EPA
822/R-85-100); National Strategy for the Development of Regional
Nutrient Criteria (EPA 822-R-98-002); and EPA Review and Approval of
State and Tribal Water Quality Standards (65FR24641).
You can find these publications through EPA's National Service
Center for Environmental Publications (NSCEP, previously NCEPI) or on
the Office of Science and Technology's Home-page (http://www.epa.gov/waterscience).
Dated: December 23, 2009.
Peter S. Silva,
Assistant Administrator for Water.
[FR Doc. E9-30992 Filed 12-29-09; 8:45 am]
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