E6-2558. Notice of Availability of Final Aquatic Life Ambient Water Quality Criteria for Nonylphenol

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability.

SUMMARY:

The Environmental Protection Agency (EPA) announces the availability of final recommended aquatic life ambient water quality criteria for nonylphenol. The Clean Water Act (CWA) requires EPA to develop and publish, and from time to time revise, criteria for water accurately reflecting the latest scientific knowledge. These criteria provide EPA's recommendations to states and authorized tribes as they establish their water quality standards as state or tribal law or regulation. An EPA water quality criterion does not substitute for CWA or EPA regulations, nor is it a regulation. It does not impose legally binding requirements on the EPA, states, authorized tribes or the regulated community. State and tribal decision makers have discretion to adopt approaches that differ from EPA's guidance on a case-by-case basis.

ADDRESSES:

Copies of the criteria document entitled, Aquatic Life Ambient Water Quality Criteria—Nonylphenol—Final (EPA-822-R-05-005) may be obtained from EPA's Water Resource Center by phone at [phone], or by e-mail to [e-mail] or by conventional mail to: U.S. EPA Water Resource Center, 4101T, 1200 Pennsylvania Avenue NW., Washington, DC 20460. You can also download the document from EPA's Web site at http://www.epa.gov/​waterscience/​criteria/​nonylphenol/​.

FOR FURTHER INFORMATION CONTACT:

Dr. Frank Gostomski, Health and Ecological Criteria Division (4304T), U.S. EPA, 1200 Pennsylvania Avenue NW., Washington, DC 20460; [phone]; [e-mail].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Interested Entities

Entities potentially interested in today's notice are those that produce, use, or regulate nonylphenol. Categories and entities interested in today's notice include:

Category	Examples of interested entities
State/Local/Tribal Government	States and Tribes.
Nonylphenol Dischargers	Sewage treatment plants.
Nonylphenol Users	Producers of surfactants.

This table is not intended to be exhaustive, but rather provides a guide for readers regarding the entities likely to be interested in this notice. Other types of entities not listed in the table could also be interested.

B. How Can I Get Copies of This Document and Other Related Information?

1. Docket. EPA has established an official public docket for this notice under Docket ID No. OW-2003-0080. The official public docket also consists of the draft criteria document, and scientific views received. Although a part of the official docket, the public docket does not include Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Publicly available docket materials are available either electronically through http://www.regulations.gov or in hard copy at the Water Docket in the EPA Docket Center, (EPA/DC) EPA West, Room B102, 1301 Constitution Ave., NW., Washington, DC. The EPA Docket Center 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], and the telephone number for the Water Docket is [phone]. To view these documents and materials, please call ahead to schedule an appointment. Every user is entitled to copy 266 pages per day before incurring a charge. The Docket may charge 15 cents a page for each page over the 266-page limit plus an administrative fee of $25.00.

2. Electronic Access. You may access this Federal Register document electronically through the EPA's Internet listings under the Federal Register at http://www.epa.gov/​fedrgstr/​.

II. Background and Today's Notice

A. What Are EPA Recommended Ambient Water Quality Criteria?

An EPA recommended ambient water quality criterion is a level of a pollutant or other measurable substance in water that, when met, will protect aquatic life and/or human health. Section 304 (a) of the Clean Water Act (CWA) requires EPA to develop and publish and, from time to time, revise, recommended ambient water quality criteria to accurately reflect the latest scientific knowledge. Ambient water quality criteria developed under section 304 (a) provide guidance to states and tribes in adopting water quality criteria into their water quality standards under section 303 (c) of the CWA. Once adopted by a state or tribe, the water quality standards are then a basis for developing regulatory controls on the discharge or release of pollutants and other alterations of water quality. EPA's section 304 (a) criteria also provide a scientific basis for EPA to develop any necessary federal water quality regulations under section 303 (c) of the CWA.

The recommended criteria in today's notice are based on the factors specified in Section 304(a) of the Clean Water Act, including the kind and extent of effects of the pollutant on human health and aquatic organisms. EPA's recommended criteria are used by the states and tribes in developing their regulatory criteria under Section 303(c) of the CWA. Under the Clean Water Act, regulatory criteria must protect the designated use, independent of the economic and technical feasibility of meeting the criteria. Economic and technical feasibility factors are considered by states and tribes when they adopt designated uses into their water quality standards under Section 303(c) of the Act and when states, tribes, and EPA consider variance requests for regulatory controls. Moreover, states and tribes may also consider alternative scientifically-defensible approaches to adopting criteria into their water quality standards.

B. What Is Nonylphenol and Why Are We Concerned About It?

Nonylphenol is an organic chemical used primarily as an intermediate to produce nonionic surfactants of the nonylphenol ethoxylate type. It is produced in large quantities in the United States. It is toxic to aquatic organisms and is found in ambient waters. Environmental exposure occurs mainly from its release as a breakdown product from industrial and domestic sewage treatment plant effluents. Nonylphenol is moderately soluble and resistant to natural degradation in water. Because of nonylphenol's toxicity, chemical properties, and widespread use as a chemical intermediate, concerns have been raised over the potential risks to aquatic organisms posed by exposure to it. For these reasons, EPA has developed ambient water quality criteria for nonylphenol.

C. What Are the National Recommended Ambient Water Quality Criteria for Nonylphenol?

Freshwater: Aquatic life should not be affected unacceptably if the:

One-hour average concentration of nonylphenol does not exceed 28 μg/L more than once every three years on the average (Criteria Maximum Concentration (CMC) or Acute Criterion); and Four-day average concentration of nonylphenol does not exceed 6.6 μg/L more than once every three years on the average (Criteria Continuous Concentration (CCC) or Chronic Criterion).

Saltwater: Aquatic life should not be affected unacceptably if the:

One-hour average concentration of nonylphenol does not exceed 7.0 μg/L more than once every three years on the average (Criteria Maximum Concentration (CMC) or Acute Criterion); and Four-day average concentration of nonylphenol does not exceed 1.7 μg/L more than once every three years on the average (Criteria Continuous Concentration (CCC) or Chronic Criterion).

D. Why Is EPA Notifying the Public About the Final Aquatic Life Ambient Water Quality Criteria for Nonylphenol and How Did the Criteria Change?

Today, EPA is notifying the public that the final aquatic life ambient water quality criteria for nonylphenol are available. In a separate Federal Register on January 5, 2004 (69 FR 340), EPA notified the public that draft aquatic life ambient water quality criteria for nonylphenol were available and solicited scientific input. Based on the information and data submitted, EPA revised the draft criteria and is now making the final aquatic life ambient water quality criteria for nonylphenol available to the public. The freshwater acute criterion of 28 μg/L did not change. Recalculation of the final acute/chronic ratio for nonylphenol resulted in changing the final freshwater chronic criterion from 5.9 μg/L to 6.6 μg/L. The saltwater acute criterion changed from 6.7 μg/L to 7.0 μg/L. The saltwater chronic criterion changed from 1.4 μg/L to 1.7 μg/L.

E. What Other Activities Is EPA Engaged in Related to Nonylphenol?

As part of its Environmental Stewardship program, EPA is developing the Safer Detergents Stewardship Initiative (SDSI). The SDSI would help ensure the health, safety, and vitality of U.S. waters by encouraging the development, manufacture, and use of safer detergents.

The Agency is initiating this new program, in part, because of the increasing levels of nonylphenol in certain receiving streams, which appear to correlate with increasing production and use of nonylphenol ethoxylate surfactants. By encouraging the manufacture and use of safer surfactants, the SDSI aims to reduce the quantity of nonylphenol ethoxylates discharged to ambient waters. The SDSI and the recommended ambient water quality criteria for nonylphenol complement one another as components in EPA's efforts to protect U.S. waters.

SDSI is cosponsored by the Office of Prevention, Pesticides and Toxic Substances (OPPTS) and the Office of Water (OW). To learn more about the SDSI, visit http://www.epa.gov/​dfe/​ or for further information, contact David DiFiore, Economics, Exposure and Technology Division (7406M), U.S. EPA, 1200 Pennsylvania Avenue, NW., Washington, DC 20460; [phone]; [e-mail].

Dated: February 16, 2006.

Ephraim S. King,

Director, Office of Science and Technology.