[Federal Register Volume 74, Number 71 (Wednesday, April 15, 2009)]
[Pages 17484-17487]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-8638]



[EPA-HQ-OW-2009-0224; FRL-8892-5]

Ocean Acidification and Marine pH Water Quality Criteria

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of data availability (NODA).


SUMMARY: This NODA provides interested parties with information 
submitted to EPA on ocean acidification and solicits additional 
pertinent data or information that may be useful in addressing this 
issue. In addition, EPA is notifying the public of its intent to review 
the current aquatic life criterion for marine pH to determine if a 
revision is warranted to protect the marine designated uses of States 
and Territories pursuant to Section 304(a)(1) of the Clean Water Act. 
The NODA also solicits additional scientific information and data, as 
well as ideas for effective strategies for Federal, State, and local 
officials to address the impacts of ocean acidification. This 
information can then be used as the basis for a broader discussion of 
ocean acidification and marine impacts. EPA also requests information 
pertaining to monitoring marine pH and implementation of pH water 
quality standards.

DATES: Comments must be received on or before June 15, 2009.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OW-
2009-0224, 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 2822T; 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-
0224. 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.
    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 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 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].


I. General Information

A. Does This Action Apply to Me?

    1. This information may be useful to scientists involved in 
studying mechanisms of carbon dioxide absorption, conversion, and 
retention in marine waters as well as those studying the effects of the 
formation of carbonic acids and lowered pH on altered carbon cycles and 
carbonate structures necessary to aquatic life.
    2. This information may be useful to Federal, State, Tribal, and 
Territorial managers of water quality programs.
    3. This information may be useful to ocean and coastal managers.

B. What Should I Consider as I Prepare My Comments for EPA?

    Information submitted in response to this NODA should address the 
nature and characteristics of altered carbon chemistry in marine 
waters, including changes in pH and biological calcification processes. 
It should also address the significance of potential modification to 
the national marine pH criterion for State and Federal Water Programs 
authorized by the Clean Water Act. EPA is soliciting additional 
scientific information, data and ideas for effective strategies for 
Federal, State, and local officials to use to address the potential 
impacts of ocean acidification. Specifically:
    1. EPA is soliciting technical information on measurement of ocean 
acidification in marine coastal waters, including:
    a. Technological advances in rapid, continuous, or remote 
measurement of pH;
    b. Long-term empirical pH data and carbon chemistry measurements, 
especially those that may demonstrate ocean acidification;
    c. Empirical data to demonstrate spatial and temporal variability 
of pH in near-coastal waters;
    d. Methods to statistically evaluate variability of pH in near-
coastal waters;
    e. Other approaches (e.g., carbon chemistry), methods and 
indicators that could reflect ocean acidification.
    2. EPA is soliciting technical information on effects of ocean 
acidification on marine biota, including:
    a. Survival, growth, reproduction, and recruitment of reef-building 
corals and crustose coralline algae;

[[Page 17485]]

    b. Anticipated persistence of coral reef communities under future 
pH scenarios;
    c. Survival, growth, reproduction, and recruitment of other (non-
coral) marine calcifying organisms;
    d. Potential changes in community structure and marine trophic 
    e. Variability of effects in tropical, temperate and polar regions;
    f. Estimates of response rates (e.g., rapid, gradual, non-linear) 
of populations and communities to ocean acidification;
    g. Adaptability to ocean acidification and broad implications for 
ecosystem resilience;
    h. Methods or estimates of the combined and relative importance of 
ocean acidification in concert with other natural and anthropogenic 
stressors (e.g., storm damage, pollution, overfishing).
    3. EPA is soliciting scientific views on the information presented 
in the bibliography of this notice.
    4. EPA is soliciting information related to EPA's current CWA 
304(a) recommended pH criterion for marine waters, including how the 
criterion could be best expressed, particularly with respect to natural 
    5. EPA is soliciting information regarding State and Territorial 
implementation of the pH criterion related to new information on ocean 
    6. EPA is soliciting potential strategies for State and Federal 
water programs to coordinate and enhance Federal data collection 
efforts, including:
    a. Approaches to designated uses for water quality standards that 
account for different pH regimes (e.g., specific designated uses for 
areas with organisms that may be more sensitive to significant pH 
fluctuations such as coral, shellfish, other calcifying organisms) (CFR 
131.10, for additional information on designated uses http://www.epa.gov/waterscience/standards/about/uses.htm);
    b. Scientifically defensible approaches to set and monitor pH 
    7. EPA is soliciting information that may be used to develop 
guidance and information on ocean acidification pursuant to Clean Water 
Act Section 304(a)(2) for States and the public. This information may 
include information on the mechanisms of ocean acidification, 
methodology development for analysis, and statistical analysis.

II. Background on Ocean Acidification

    Ocean acidification refers to the decrease in the pH of the Earth's 
oceans caused by the uptake of carbon dioxide (CO2) from the 
atmosphere. Oceans have been absorbing about one-third of the 
anthropogenic CO2 emitted into the atmosphere since pre-
industrial times. As more CO2 dissolves in the ocean, it 
reduces ocean pH, which changes the chemistry of the water. These 
changes present potential risks across a broad spectrum of marine 
    Biological effects are projected based on models that predict lower 
pH regimes in marine waters over the next 50-100 years. Using these 
predictions, reduced pH conditions and/or increased CO2 
saturation have been simulated in the lab and have shown the potential 
to impact marine life. The majority of the effects observed in lab 
studies have occurred at pH levels beyond the allowed variability of 
0.2 units in the CWA 304(a) recommended criteria for marine pH. For 
instance, ocean acidification related reductions in pH is forecast to 
reduce calcification rates in corals and may affect economically 
important shellfish species including oysters, scallops, mussels, 
clams, sea urchins, crabs, and lobsters. A recent field study on marine 
plankton described reduced shell weight over time ``consistent with 
reduced calcification today induced by ocean acidification'' (Moy et 
al. 2009). One study demonstrated effects at pH changes of less than 
0.2, describing effects on squid metabolism (0.2 is the allowed pH 
variation from normal conditions under current EPA criteria 
recommendation) (Portner 2008). Impacts to shellfish and other 
calcifying organisms that represent the base of the food web may have 
implications for larger organisms that depend on shellfish and other 
calcifying organisms for prey.
    Current research indicates the impact of ocean acidification on 
marine organisms will largely be negative, and the impacts may differ 
from one life stage to another. There may be interactions between 
CO2 saturation, temperature, and other stressors which are 
not fully understood. Preliminary projections indicate that oceans will 
become more acidic over time and overall, the net effect is likely to 
disrupt the normal functioning of many marine and coastal ecosystems.
    The first comprehensive national study of how CO2 
emissions are absorbed into the oceans has been commissioned by the 
National Oceanic and Atmospheric Administration (NOAA). The National 
Academies' Committee on the Development of an Integrated Science 
Strategy for Ocean Acidification Monitoring, Research, and Impacts 
Assessment is charged with recommending priorities for a national 
research, monitoring, and assessment plan to advance understanding of 
the biogeochemistry of carbon dioxide uptake in the ocean and the 
relationship to atmospheric levels of carbon dioxide, and to reduce 
uncertainties in projections of increasing ocean acidification and the 
potential effects on living marine resources and ocean ecosystems. The 
18-month project started on September 16, 2008 (http://dels.nas.edu/osb/acidification.shtml).

A. Examples of EPA Activities and Publications Related to Ocean 

    EPA is currently involved in a number of initiatives both solely 
and in partnership with other Federal agencies. Below is a list of 
current and future projects related to the issue of ocean 
acidification, the development of biocriteria to help classify and 
protect marine resources, and tools for the assessment of potential 
impacts to marine resources that comprise marine designated uses.
     EPA released the ``Stony Coral Rapid Bioassessment 
Protocol'' (RBP); EPA/600/R-06/167, July 2007, which provides a 
methodology for assessing the health and condition of stony corals, 
calcifying organisms that are sensitive to ocean acidification. Use of 
the RBP by interested States and Territories provides the ability to 
establish a baseline for coral reef structural health, provides the 
capacity to derive biocriteria for corals and reef structures, and 
provides a scientifically defensible method for assessing use 
attainment in marine waters, as well as evaluating the impact of 
stressors, such as ocean acidification on corals and coral reef 
structures. http://www.epa.gov/bioiweb1/coral/coral biocriteria.html.
     EPA is also developing a technical guidance framework to 
aid States and Territories in their development, adoption, and 
implementation of coral reef biocriteria in their respective water 
quality standards. EPA plans to publish this coral biocriteria 
framework document by December 2009 to assist in this effort. This 
document will complement the ``Stony Coral Rapid Bioassessment 
Protocol'' (RBP) described above.
     EPA has supported the development of the Coral Mortality 
and Bleaching Output (COMBO) model to project the effects of climate 
change on coral reefs by calculating impacts from changing sea surface 
temperature and CO2 concentration, and from episodic high 
temperature bleaching events. Having been applied to Hawaii and the 
Eastern Caribbean, the model is intended to serve as a tool for climate

[[Page 17486]]

change policy analysis, and for use by resource managers and biologists 
in projecting coral reef impacts at local-to-regional scales.
     The Coastal Research and Monitoring Strategy presents a 
basic assessment of the Nation's coastal research and monitoring needs, 
and recommends an integrated framework to address the needs of the 
Nation and the coastal States and Tribes in order to protect vital 
coastal resources. http://www.epa.gov/owow/oceans/nccr/H2Ofin.pdf.
     The National Coastal Condition Report III (NCCR III), 
December 2008, is the third in a series of reports describing the 
ecological health of U.S. coastal waters at a regional and national 
scale. First issued in 2001 and updated periodically thereafter, the 
NCCR is one of only a few statistically-significant measures of U.S. 
water quality on a nationwide basis. NCCR III assesses the condition of 
the Nation's coastal waters, including Alaska and Hawaii, based 
primarily on coastal monitoring data collected in 2001 and 2002. It 
presents an analysis of temporal changes in estuarine condition from 
1990 to 2002 for the Nation's coastal waters and by region. http://www.epa.gov/owow/oceans/nccr3/downloads.html.
     EPA, working with other Federal agencies, as well as 
State, regional, and local partners, undertakes site-specific 
monitoring of coastal and ocean waters. For example, EPA and the State 
of Florida, in consultation with NOAA, implement the Water Quality 
Protection Program (WQPP) for the Florida Keys National Marine 
Sanctuary. The WQPP includes a water quality monitoring program which 
has funded three long-term monitoring projects: overall water quality; 
coral reef and hardbottom community health; and seagrass community 
health. http://www.epa.gov/region4/water/coastal/index.html.

III. What Are Water Quality Criteria?

    Water quality criteria are scientifically derived 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 the chemical concentrations in 
ambient water. Section 304(a)(2) requires EPA to develop and publish 
and, from time to time, revise, information, including information on 
factors necessary to restore and maintain the integrity of navigable 
waters, ground waters, waters of the contiguous zone, and the oceans; 
protection and propagation of shellfish, fish, and wildlife; and 
measurement and classification of water quality.
    Section 304(a) recommended 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, recreational use, 
industrial use). EPA's section 304(a) 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 defensible 
water quality standards that differ from these recommendations.

A. Why Is EPA Reviewing the Aquatic Life Criteria for pH for Marine 

    EPA's current CWA 304(a) recommended criterion for marine pH 
states: ``pH range of 6.5 to 8.5 for marine aquatic life (but not 
varying more than 0.2 units outside of the normally occurring range)''. 
This criterion applies to open-ocean waters within 3 miles of a State 
or Territory's shoreline where the depth is substantially greater than 
the euphotic zone.
    On December 17, 2007, EPA received a petition from the Center for 
Biological Diversity asking EPA to revise its recommended national 
marine pH water quality criterion for the protection of aquatic life 
and also asked EPA to publish information and provide guidance on ocean 
    Following careful consideration of the petitioner's request and 
supporting information, EPA is issuing this notice to solicit 
additional scientific information and data to fill data gaps to inform 
EPA's next steps and determine whether changes in existing criteria are 
    In this NODA, EPA is only requesting information and data relevant 
to addressing ocean acidification under the CWA. After the comment 
period closes on this NODA, EPA plans to evaluate the information 
received in considering whether the revision of the recommended marine 
pH criterion is warranted at this time. EPA intends to make final its 
decision regarding the evaluation of the information received within 
one year. If necessary, additional public review and comment will be 
requested during revision of the pH criterion.

IV. References Related to Ocean Acidification

America's Living Oceans (``Living Oceans''), Final Report of the Pew 
Oceans Commission, pg. 90 (2003).
Andersson, A.J., et al., Coastal Ocean CO2--Carbonic 
Acid--Carbonate Sediment System of the Anthropocene. Global 
Biogeochemical Cycles, 20:GB1S92 (2006).
Andersson, A.J.; Mackenzie, F.T.; Bates, N.R. Life on the Margin: 
Implications of Ocean Acidification on Mg-calcite, High Latitude and 
Cold-Water Marine Calcifiers. Marine Ecology (ISSN: 0171-8630); 
Volume 373, No., pp. 265-273; 2008.
Atkinson, M.J.; Cuet, P. Possible Effects of Ocean Acidification on 
Coral Reef Biogeochemistry: Topics for Research. Marine Ecology 
(ISSN: 0171-8630); Volume 373, No., pp. 249-256; 2008.
Balch, W.M.; Fabry, V.J. Ocean Acidification: Documenting its Impact 
on Calcifying Phytoplankton at Basin Scales. Marine Ecology (ISSN: 
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Bindoff, N.L., et al., Chapter 5: Observations: Oceanic Climate 
Change and Sea Level, Climate Change 2007: The Physical Science 
Basis. Contribution of Working Group I to the Fourth Assessment 
Report of the IPCC (2007).
Bradley, P., W. Davis, W. Fisher, H. Bell, V. Chan, C. LoBue, W. 
Wiltse. Biological criteria for protection of U.S. coral reefs. 
Proceedings of the 11th International Coral Reef Symposium, July 7-
11, 2008.
Buddemeier, R.W., P.L. Jokiel, K.M. Zimmerman, D.R. Lane, J. M. 
Carey, G.C. Bohling, J.A. Martinich. (2008) A modeling tool to 
evaluate regional coral reef responses to changes in climate and 
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Caldeira, K. & Wickett M.E., Anthropogenic Carbon and Ocean pH. 
Nature 425:365 (2003).
Caldeira, K. and 25 others, Comment on ``Modern-age Buildup of 
CO2 and Its Effects on Seawater Acidity and Salinity'' by 
Hugo A. Lo[aacute]iciga. Geophysical Research Letters 34:L18608 
Chavez, F.P., et al., Chapter 15: Coastal Oceans, North American 
Carbon Budget and Implications for the Global Carbon Cycle, U.S. 
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Dore, J., et al., Climate-driven changes to the atmospheric 
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[[Page 17487]]

Dupont, S.; Havenhand, J.; Thorndyke, W.; Peck, L.; Thorndyke, M. 
Near-future Level of CO2-driven Ocean Acidification 
Radically Affects Larval Survival and Development in the Brittlestar 
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Feely, R.A., et al., Carbon Dioxide and Our Ocean Legacy (2006).
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CaCO3 System in the Oceans. Science 305:362-366 (2004).
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Detecting Anthropogenic CO2 in the Oceans. Global 
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Guionette, J.M, et al., Will Human-induced Changes in Seawater 
Chemistry Alter the Distribution of Deep-Sea Scleractinian Corals? 
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in the Cephalopod Sepia Offpicinalis under Elevated Seawater 
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    Dated: April 9, 2009.
Michael H. Shapiro,
Acting Assistant Administrator for Water.
[FR Doc. E9-8638 Filed 4-14-09; 8:45 am]