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Nutrient Criteria Development; Notice of Ecoregional Nutrient Criteria

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Information about this document as published in the Federal Register.

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Environmental Protection Agency (EPA).


Notice of Ecoregional Nutrient Criteria for Lakes and Reservoirs, and Rivers and Streams.


Pursuant to Section 304(a) of the Clean Water Act (CWA), the Environmental Protection Agency (EPA) announces the publication and availability of nine additional Section 304(a) ecoregional nutrient criteria documents for lakes and reservoirs, and rivers and streams within specific geographic regions (ecoregions) of the United States. These nine documents supplement the seventeen ecoregional nutrient criteria documents for lakes and reservoirs, rivers and streams and wetlands announced by EPA on January 9, 2001 (66 FR 1671). These documents give States, Territories, and authorized Tribes (Hereafter, this Federal Register Notice refers to these entities as “States and authorized Tribes.” Throughout this document, reference to States and Start Printed Page 9270Authorized Tribes is intended to include Territories) information to develop numeric nutrient criteria for lakes and reservoirs, rivers and streams, and wetlands within several different nutrient ecoregions. An ecoregion is a geographic area with assumed relative homogeneity of ecological characteristics. EPA's section 304(a) criteria recommendations represent enrichment conditions (total phosphorous, total nitrogen, chlorophyll a and some form of water clarity, i.e. Secchi depth or turbidity) of surface waters that are minimally affected by human activities and to provide for the protection and propagation of aquatic life and recreation. Draft criteria documents have undergone external peer review, and a summary of these comments is available on EPA's Internet website: (​ost/​standards/​nutrient.html).

While the nine documents available today contain EPA's scientific recommendations regarding ecoregional nutrient criteria, the information and recommendations are not regulations and do not impose legally binding requirements on EPA, States, authorized Tribes, or the public. They may not apply to a particular situation based upon the circumstances. States and authorized Tribes retain the discretion to adopt water quality criteria that differ from these recommendations based on other scientifically defensible approaches to developing regional or local nutrient criteria. EPA may revise these section 304(a) water quality criteria recommendations in the future.

EPA is making these recommended section 304(a) nutrient water quality criteria available to the public in accordance with the Agency's process for publishing new and revised criteria (see Federal Register, December 10, 1998, 63 FR 68354 and in the EPA document titled, “National Recommended Water Quality—Correction,” EPA 822-Z-99-001, April 1999). EPA invites the public to provide scientific views on these criteria. EPA will review and consider information submitted on significant scientific issues and site-specific data that might not have otherwise been identified by the Agency during development of these criteria. After EPA reviews the new information, the Agency may publish revised nutrient water quality criteria recommendations or publish a notice informing the public that the submitted information does not warrant revision of the criteria.

EPA encourages the public to provide additional data that could help States and or authorized Tribes refine these recommended nutrient water quality criteria. EPA identified specific sections within each document where the public could greatly assist States and authorized Tribes in the task of augmenting the database for deriving ecoregional nutrient water quality criteria. For example, the public can provide information about the historical conditions and trends of the water resources within an ecoregion related to eutrophication resulting from human activities. EPA will forward all comments received on a particular ecoregional criterion or set of criteria to the appropriate State or Tribe to help foster water quality criteria refinement.

EPA's Office of Water, Office of Science and Technology prepared this document. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.


EPA will accept significant scientific information submitted to the Agency within 90 days of publication of this notice in the Federal Register. You should adequately document any scientific information and provide enough supporting information to indicate that acceptable and scientifically defensible procedures were used and that the results are reliable.


You can get copies of the set or any document from the U.S. National Service Center for Environmental Publications (NSCEP), 11029 Kenwood Road, Cincinnati, OH 45242; (513) 489-8190 or toll free (800) 490-9198. The documents are also available electronically at​waterscience/​standards/​nutrient.html. The waterbody-specific technical guidance manuals, which present the nutrient criteria derivation methodology used by EPA to develop the nutrient water quality criteria, are also available from EPA's nutrient website. Please send an original and two copies of written significant scientific information to Robert Cantilli (MC-4304), U.S. EPA, Ariel Rios Building, 1200 Pennsylvania Ave., NW , Washington, DC 20460. Written significant scientific information may be submitted electronically in ASCII or Word Perfect 5.1, 5.2, 6.1, 8.0 or 9.0 formats to

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Robert Cantilli, U.S. EPA, Health and Ecological Criteria Division (4304), Office of Science and Technology, Ariel Rios Building, 1200 Pennsylvania Ave., NW, Washington, DC 20460; or call (202) 566-1091; or e-mail

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States and Tribes consistently identify excessive levels of nutrients as a major reason why as much as half of the surface waters surveyed in this country do not meet water quality objectives, such as full support of aquatic life. In 2000, EPA published nutrient criteria technical guidance manuals for lakes and reservoirs and for rivers and streams, and in 2001 EPA published a draft guidance manual for estuarine and coastal marine waters. These manuals provide techniques for assessing nutrient conditions as well as methods for developing nutrient criteria for specific water body types. These and related documents are available from EPA's nutrient website:​waterscience/​standards/​nutrient.html. EPA is currently developing a guidance manual for wetlands.

In addition to developing guidance for specific waterbody types, EPA will publish specific nutrient water quality criteria recommendations under section 304(a) for every type of waterbody (where applicable) for all of the 14 nutrient ecoregions that EPA identified in the continental United States. On January 9, 2001, EPA announced the availability of ecoregional nutrient criteria documents for lakes and reservoirs in eight ecoregions, for rivers and streams in eight ecoregions (several of which overlap with the eight ecoregions for lakes and reservoirs), and for wetlands in one ecoregion. Those ecoregions were chosen based on the availability of nutrient data within each ecoregion. Today, EPA announces the availability of nine additional ecoregional nutrient criteria documents for lakes and reservoirs, and rivers and streams in ecoregions for which criteria recommendations were not developed in January 2001. These nine bring the total of ecoregional nutrient criteria documents to 26 and results in nutrient criteria covering about 90% of the freshwater waterbodies of the U.S. (excluding wetlands).

EPA also provided guidance on development and adoption of nutrient criteria into water quality standards. More recently, on November 14, 2001, Geoffrey H. Grubbs, Director of the Office of Science and Technology, in EPA's Office of Water provided this guidance to EPA, and State and Interstate Water Program Directors. This memorandum can be viewed electronically at:​waterscience/​standards/​nutrient.html

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Dated: February 15, 2002.

Geoffrey H. Grubbs,

Director, Office of Science and Technology.

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[FR Doc. 02-4790 Filed 2-27-02; 8:45 am]