04-1107. Notice of Availability of Draft Revised Ambient Water Quality Criteria Document for Chloroform and Request for Scientific Views

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability and request for scientific views.

SUMMARY:

This notice informs the public about the availability of and requests scientific views on a revised draft human health criteria document for chloroform. The Agency derived the revised criteria according to the procedures and methods in EPA's Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health (2000) (2000 Human Health Methodology).

The Clean Water Act (CWA) requires the Environmental Protection Agency (EPA) to develop and publish and, from time to time, revise criteria for water accurately reflecting the latest scientific knowledge. When final, these criteria will provide EPA's recommendations to States and authorized Tribes as they establish their water quality standards as State or Tribal law or regulation. At this time the Agency is not making final recommendations. Rather the Agency is requesting scientific views on the draft revised criteria because the criteria reflect changes in several of the values used to derive them, including the Reference Dose (RfD), the Relative Source Contribution (RSC) and Bioaccumulation Factors.

DATES:

All scientific information must be submitted to the Agency on or before March 22, 2004.

ADDRESSES:

Scientific views may be submitted electronically, by mail, or through hand-delivery/courier. Follow detailed instructions as provided in section I.C. of the SUPPLEMENTARY INFORMATION section. Copies of the criteria document entitled, Ambient Water Quality Criteria for the Protection of Human Health: Chloroform—Revised Draft (EPA-822-R-04-002) 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: 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/​humanhealth/​docs/​.

FOR FURTHER INFORMATION CONTACT:

Dr. Tala Henry, 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 chloroform. Categories and entities interested in today's notice include:

Category	Examples of interested entities
State/Local/Tribal Government	States and Tribes
Industries discharging pollutants to surface waters	Paper and pulp mills, steam electric generators, organic chemicals/petroleum refining.
Publically-owned treatment works discharging pollutants to surface waters	Drinking water treatment plants, wastewater treatment plants.

This table is not intended to be exhaustive, but rather provides a guide for readers regarding entities likely to be interested in this notice. This table lists the types of entities that EPA is now aware could potentially 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-2003-0082. The official public docket consists of the documents specifically referenced in this notice, any scientific views received, and other information related to this notice. 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. The official public docket is the collection of materials that is available for public viewing 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 Office of Water Docket is [phone]. To view these 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 Internet under the “Federal Register” listings at http://www.epa.gov/​fedrgstr/​.

An electronic version of the public docket is available through EPA's electronic public docket and comment system, EPA Dockets. You may use EPA Dockets at http://www.epa.gov/​edocket/​ to submit or read the scientific views, access the index listing of the contents of the official public docket, and to access those documents in the public docket that are available electronically. Once in the system, select “search,” then key in the appropriate docket identification number.

Certain types of information will not be placed in the EPA Dockets. Information claimed as CBI and other information whose disclosure is restricted by statute is not included in the official public docket. EPA's policy is that copyrighted material will not be placed in EPA's electronic public docket but will be available only in printed, paper form in the official public docket. To the extent feasible, publicly available docket materials will be made available in EPA's electronic public docket. When a document is selected from the index list in EPA Dockets, the system will identify whether the document is available for viewing in EPA's electronic public docket. Although not all docket materials may be available electronically, you may still access any of the publicly available docket materials through the docket facility identified in Section I.B.1.

It is important to note that EPA's policy is that scientific views, whether submitted electronically or in paper, will be made available for public viewing in EPA's electronic public docket as EPA receives them and without change, unless your views and information contain copyrighted material, CBI, or other information whose disclosure is restricted by statute. When EPA identifies a scientific view containing copyrighted material, EPA will provide a reference to that material in the version of the view that is placed in EPA's electronic public docket. The entire printed scientific view, including the copyrighted material, will be available in the public docket.

Scientific views submitted on computer disks that are mailed or delivered to the docket will be transferred to EPA's electronic public docket. Scientific views that are mailed or delivered to the Docket will be scanned and placed in EPA's electronic public docket. Where practical, physical objects will be photographed, and the photograph will be placed in EPA's electronic public docket along with a brief description written by the docket staff.

C. How and to Whom Do I Submit My Scientific Views?

You may submit scientific views electronically, by mail, or through hand delivery/courier. To ensure proper receipt by EPA, identify the appropriate docket identification number in the subject line on the first page of your scientific views. Please ensure that your scientific views are submitted within the specified time period. Scientific views received after the close of the stated time period will be marked “late.” EPA is not required to consider these late scientific views.

1. Electronically. If you submit electronic information as prescribed below, EPA recommends that you include your name, mailing address, and an e-mail address or other contact information in the body of your scientific views. Also include this contact information on the outside of any disk or CD ROM you submit, and in any cover letter accompanying the disk or CD ROM. This ensures that you can be identified as the submitter of the scientific information and allows EPA to contact you in case EPA cannot read your scientific views due to technical difficulties or needs further information on the substance of your scientific views. EPA's policy is that EPA will not edit your scientific views, and any identifying or contact information provided in the body of the scientific views will be included as part of the scientific views that are placed in the official public docket, and made available in EPA's electronic public docket. If EPA cannot read your scientific views due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your scientific views.

i. EPA Dockets. Your use of EPA's electronic public docket to submit scientific views to EPA electronically is EPA's preferred method for receiving scientific views. Go directly to EPA Dockets at http://www.epa.gov/​edocket/​ and follow the online instructions for submitting scientific views. To access EPA's electronic public docket from the EPA Internet Home page, select “Information Sources,” “Dockets,” and “EPA Dockets.” Once in the system, select “search,” and then key in Docket ID No. OW-2003-0082. The system is an “anonymous access” system, which means EPA will not know your identity, e-mail address, or other contact information unless you provide it in the body of your input.

ii. E-mail. Scientific views may be sent by electronic mail (e-mail) to: [e-mail], Attention Docket ID No. OW-2003-0082. In contrast to EPA's electronic public docket, EPA's e-mail system is not an “anonymous access” system. If you send an e-mail with scientific views directly to the Docket without going through EPA's electronic public docket, EPA's e-mail system automatically captures your e-mail address. E-mail addresses that are automatically captured by EPA's e-mail system are included as part of the information that is placed in the official public docket, and made available in EPA's electronic public docket.

iii. Disk or CD ROM. You may submit scientific views on a disk or CD ROM that you mail to the mailing address identified in Section I.C.2. These electronic submissions will be accepted in WordPerfect 9, or higher, or ASCII file format. Avoid the use of special characters and any form of encryption.

2. By Mail. Send your scientific views to: Water Docket in the EPA Docket Center, Environmental Protection Agency, Mailcode 4101T, 1200 Pennsylvania Ave., NW., Washington, DC, 20460, Attention Docket ID No. OW-2003-0082.

3. By Hand Delivery or Courier. Deliver your scientific views to: Water Docket, EPA Docket Center, EPA West, Room B102, 1301 Constitution Ave., NW., Washington, DC, Attention Docket ID No. OW-2003-0082. Such deliveries are only accepted during the Docket's normal hours of operation as identified in section I.B.1.

D. What Should I Consider as I Prepare My Scientific Views for EPA?

You may find these suggestions helpful for preparing your scientific views:

1. Explain your scientific views as clearly as possible.

2. Describe any assumptions that you used.

3. Provide any technical information and/or data you used that support your scientific views.

4. Provide specific examples to illustrate your concerns.

5. Offer alternatives.

6. Make sure to submit your scientific views by the time period deadline identified.

7. To ensure proper receipt by EPA, identify the appropriate docket identification number in the subject line on the first page of your response. It would also be helpful if you provided the name, date, and Federal Register citation related to your views.

II. Background and Today's Notice

A. What are Recommended Water Quality Criteria?

Recommended water quality criteria represent the concentrations of a chemical in water at or below which human health is protected from adverse effects of the chemical. Section 304(a)(1) of 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. Water quality criteria developed under section 304(a) are based solely on data and scientific judgments. They do not consider economic impacts or the technological feasibility of meeting the criteria in ambient water. Section 304(a) criteria provide guidance to States and Tribes in adopting water quality standards. The criteria also provide a scientific basis for EPA to develop Federally promulgated water quality standards under section 303(c) of the CWA.

B. What Is Chloroform and Why Are We Concerned About it?

Chloroform (trichloromethane) is nonflammable and slightly soluble in water. Chloroform is a volatile organic liquid that has a number of industrial and chemical uses. It is manufactured and used as a solvent and as an intermediate in the production of refrigerants, plastics, and other solvents. Because of its volatility, chloroform has the potential to evaporate from water and escape from contaminated environmental media (e.g., water or soil) into air, and may also be released in vapor from some types of industrial or chemical operations. The chief reason for chloroform-related health concerns is that it is generated as a by-product during the chlorination of drinking water. Chloroform has also been detected in a wide variety of foods and beverages. Because chloroform is thought to be ubiquitous in the environment and exposure may occur from several routes of exposure, concerns have been raised over the potential risks posed by exposure of humans to it. For these reasons, EPA has developed ambient water quality criteria for chloroform.

C. Why Did EPA Revise the Chloroform Criteria?

EPA originally published Human Health AWQC for chloroform in 1980 (45 FR 79318, October 1980). These criteria were updated by incorporating newer toxicity values from EPA's Integrated Risk Information System (IRIS) data base and published in the 1992 National Toxics Rule (57 FR 60848). The criteria values promulgated in the National Toxics Rule are the same values included in EPA's most recent compilation of national recommended water quality criteria, published in 2002 (67 FR 79091). The chloroform criteria currently recommended by EPA are: 5.7 μg/L for consumption of water + organisms and 470 μg/L for consumption of organisms only. The 2002 compilation did not include updates to the chloroform criteria based on the 2000 Human Health Methodology. Rather, EPA indicated in the 2002 compilation that updates for chemicals undergoing major reassessments, including chloroform, would be published in the future. The draft revised criteria document announced in this notice is the result of that reassessment.

D. What's New in the Revised Criteria?

The draft revised criteria reflect the Agency's consideration of the recent advances in scientific information available since the 2002 criteria were recommend. We have revised the criteria by implementing EPA's Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health (2002) (EPA-822-B-00-004; 2000 Human Health Methodology). Specifically, we used new:

• Fish Consumption Rate
• Dose Response Parameter
• Relative Source Contribution (RSC)
• Bioaccumulation Factors

1. Fish Consumption Rate. The fish consumption rate used in revising the chloroform criteria is 17.5 grams per day. The value represents the 95th percentile rate for the general U.S. population. The data from which this value was derived and the scientific basis for applying this value in deriving national recommended ambient water quality criteria is described in EPA's 2000 Human Health Methodology. EPA has previously received peer review and scientific views on this value as part of developing the 2000 Human Health Methodology, and therefore, is not requesting scientific views on the fish consumption rate.

2. Dose Response Parameter. The dose response parameter used in revising the chloroform criteria is the Reference Dose (RfD) that was revised by EPA's Integrated Risk Information System (IRIS) program in October 2001 (http://www.epa.gov/​iris/​). The IRIS program performed a detailed review of toxicological information on chloroform during the process of revising the RfD (EPA-635-R-01-001). The RfD published in IRIS is 1 × 10⁻² mg/kg-day. EPA has previously received peer review and scientific views on this value as part of developing the IRIS profile and RfD, and therefore, is not requesting scientific views on the RfD.

3. Relative Source Contribution (RSC). The RSC is taken into account in deriving AWQC for non-carcinogens, and for carcinogens for which a nonlinear approach is used for low-dose extrapolation. In light of the data supporting a nonlinear low-dose extrapolation for chloroform, a RSC is needed for this chemical. EPA recently published a report, Relative Source Contribution for Chloroform (EPA-822-R-01-006, March 2001), in support of the Stage 2 Disinfectants and Disinfection Byproducts—Proposed Rule (68 FR49548). This document examines the RSC to dose through all routes of exposure. The RSC value used in revising the chloroform criteria was derived using exposure data and analysis from that document. From our exposure analysis, it was found that data were insufficient to adequately quantify the exposures from ambient water and freshwater/estuarine fish consumption. Therefore, therefore the default RSC value of 20% was used for the calculation of the AWQC. EPA is particularly interested in receiving scientific views on the data used to derive the RSC and on the value used to calculate the AWQC for chloroform.

4. Bioaccumulation Factors (BAFs). In the 2000 Human Health Methodology EPA recognized that to prevent harmful exposures to chemicals in water by eating contaminated fish and shellfish, national 304(a) water quality criteria for the protection of human health must address the process of chemical bioaccumulation in aquatic organisms. EPA also developed detailed procedures and methods for developing BAFs to derive or revise ambient water quality criteria in the 2000 Human Health Methodology. In deriving the revised chloroform criteria, we have implemented these procedures and methods to develop national trophic-level specific bioaccumulation factors for trophic level 2, 3 and 4 aquatic organisms. The bioaccumulation factors we derived are: 2.8 L/kg for trophic level 2, 3.4 L/kg for trophic level 3, and 3.8 L/kg for trophic level 4. The trophic level 3 and 4 BAF values were derived from laboratory-measured BCFs (Method 3) and the trophic level 2 BAF was derived from the n-octanol-water partition coefficient (K_ow) (Method 4), as described in the 2000 Human Health Methodology. EPA is particularly interested in receiving scientific views on the data used to derive the BAFs and on the value used to calculate the AWQC for chloroform.

E. What Are the Draft Revised National Recommended Water Quality Criteria for Chloroform?

The draft revised criteria for chloroform are: 68 μg/L for consumption of water + organisms and 2,400 μg/L for consumption of organisms only.

F. What Specific Scientific Issues Does EPA Want Views On?

Though the public is welcome to submit scientific views on any component of the chloroform ambient water quality criteria document, EPA is specifically interested in scientific views on the following scientific issues:

• The determination of Relative Source Contribution and the value as estimated.
• The data from which the bioaccumulation factors (BAFs) were derived and the values as estimated.

G. What Is the Status of Existing Recommended Criteria While They Are Being Revised?

Water quality criteria published by EPA are the Agency's recommended water quality criteria until EPA revises or withdraws the criteria. EPA supports using the current section 304(a) criteria for those chemicals for which criteria are being updated and considers them to be scientifically sound until the Agency publishes final revised 304(a) criteria.

Dated: December 23, 2003.

Geoffrey H. Grubbs,

Director, Office of Science and Technology.