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###### Environmental Protection Agency

          - [FRL-6700-1] 

# FOR FURTHER INFORMATION CONTACT: 

                        Any member of the public wishing further information concerning this meeting or wishing to submit brief oral comments must contact Dr. Donald Barnes, Designated Federal Officer, Science Advisory Board (1400A), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC 20460; telephone (202) 564-4533; FAX (202) 501-0323; or via e-mail at                         *barnes.don@epa.gov.*                         Requests for oral comments must be in writing (e-mail preferred) and received by Dr. Barnes no later than noon Eastern Time on May 26, 2000.                    

## 2. Drinking Water Committee (DWC) Meeting—June 5-7, 2000 

The Drinking Water Committee of the US EPA Science Advisory Board (SAB), will meet from June 5 through 7, 2000. Days one and two of the meeting, June 5 and 6, 2000, will be held at the Holiday Inn Georgetown, 2101 Wisconsin Avenue, NW, Washington, DC 20007, phone: (202) 338-4600 . On day three, June 7, 2000, the Committee will meet in conference room 6013, USEPA, Ariel Rios Building North, 1200 Pennsylvania Avenue, NW, Washington, DC 20004; phone: (202) 564-4533. The meeting will begin by 9 a.m. on June 5 and adjourn no later than 3 p.m. on June 7, 2000. 

*Purpose of the Meeting*                        —The Drinking Water Committee will conduct a review of EPA's proposed drinking water regulation for arsenic. The Committee will conduct this review in fulfillment of its responsibilities under Section 1412(e) of the Safe Drinking Water Act (SDWA as amended in August 1996) which states that:                     

The Administrator shall request comments from the Science Advisory Board (established under the Environmental Research, Development, and Demonstration Act of 1978) prior to proposal of a maximum contaminant level goal and national primary drinking water regulation. The Board shall respond, as it deems appropriate, within the time period applicable for promulgation of the national primary drinking water standard concerned. This subsection shall, under no circumstances, be used to delay final promulgation of any national primary drinking water standard. 

*Background*                        —The current National Primary Drinking Water Regulation for arsenic is 50 µg/Liter (0.05 milligrams per liter—mg/L). This regulatory level has been in effect since 1976 and is based on a U.S. Public Health Service standard whose origins date back to 1942. The 1996 Amendments to the Safe Drinking Water Act required the Agency to proceed on two tracks to update the standard: on the one hand, the Agency was directed to develop an arsenic research strategy by February 1997 designed to serve as roadmap for filling gaps in our understanding of the scientific issues surrounding arsenic and, at the same time, to work toward proposing a new primary drinking water regulation by January 1, 2000 and to promulgate a final rule by January 1, 2001.                     

                        In response, the Agency met its deadline for developing the research plan and is currently implementing the plan, together with external partners. EPA has also been updating and assembling the various risk management components that will be needed to propose a revised regulation: risk characterization, analytical methods, occurrence, treatment technologies, costs, and benefits. The most challenging of these has been the risk characterization and the underlying risk assessment of the health effects of arsenic. To assist the Agency in its efforts, EPA asked the National Academy of Sciences' National Research Council (NRC) to evaluate all relevant national and international literature concerning the health effects of arsenic and to provide the Agency with its assessment of these data and information. The NRC published its report, Arsenic in Drinking Water in March, 1999. That report concluded that studies in Taiwan, Chile, and Argentina link arsenic to skin, bladder and lung                               ( print page 30590)                            cancer and to noncancer effects. The NRC report recommended that EPA lower its MCL.                    

### Charge to the Committee—A. Arsenic Health Effects 

Charge Question 1: Concentration of inorganic arsenic as principal form causing health effects—Does the SAB have perspectives on this issue that it believes EPA should consider in developing its risk assessment? 

EPA has identified inorganic arsenic as the principal form causing health effects, and the literature indicates that most arsenic in drinking water is inorganic. EPA's MCLG and MCL do not distinguish between arsenate and arsenite. 

Charge Question 2: Implications of natural arsenic exposure through food—Does SAB agree with the implied NRC perspective that relative source contribution of food should be taken into consideration in the setting of the drinking water standard and how might we consider this and communicate it to the public? 

The 1999 NRC report estimated the daily inorganic food intake by assuming that 10% of the arsenic in seafood is inorganic, and all other foods are 100% inorganic arsenic. NRC noted that these assumptions set an upper bound on the contribution from food, which is about 10 μg a day for adults. The NRC report stated that “The significance of the intake of inorganic arsenic from food increases as the concentration of arsenic in water decreases. If [drinking] water contains 50 μg/L of inorganic arsenic, arsenic in food might not be significant. However, if [drinking] water contains 5 μg/L of arsenic and 2 L per day is consumed, the contribution of inorganic arsenic from diet and water are comparable (NRC report).” Further, “The public health significance of daily ingestion of a given amount of arsenic in drinking water will be influenced by the background levels of arsenic consumed in food (NRC report).” “Consideration of arsenic in food might affect both the dose-response relationship for arsenic in drinking water in the study population and the implications for risk from arsenic in drinking water in the United States where dietary arsenic might differ from that in the study population in Taiwan (NRC report)”. 

Charge Question 3: Accounting for Cardiovascular Health End Point—Is precautionary advice on use of low-arsenic water in preparation of infant formula appropriate given the available information? 

The NRC report was inconclusive about the health risks to the pregnant woman, developing fetus, infants, lactating women, and children. Given the potential for cardiovascular disease (as evidenced by EPA's Utah studies and extensive other data) and uncertainty about risks to infants, EPA plans to issue a health advisory to recommend use of low-arsenic water in preparation of infant formula. 

### B. Arsenic Treatment Charge for the SAB 

Charge Question 4: Decision tree for waste disposal options for arsenic treatment brines and spent media—Based upon a review of the submitted materials, does the SAB believe that the EPA produced an accurate projection of the likely disposal options for arsenic residuals and the distribution of these options by treatment type? What are the SAB's views on the advantages and the limitations of the various waste disposal options? What effect, if any, would the SAB's analysis of these advantages and limitations have on the probabilities assigned? What are the SAB's views on which options will be more likely used by small systems (less than 10,000 people), and which will be more likely used by larger ones? 

EPA identified waste disposal options that will likely be used for arsenic treatment residuals. EPA considered three types or residuals: brines or liquid wastes, sludges, and solid wastes. Ultimately, liquid wastes would be disposed at sanitary sewers, evaporation ponds, or be directly discharged. Chemical precipitation is assumed to be an intermediate step for the disposal of some brines. Sludges would be either mechanically, or non-mechanically dewatered prior to ultimate disposal at a landfill. Solid wastes would typically be disposed at non-hazardous landfills. EPA assigned national selection probabilities to each of these options in a decision tree. These probabilities are an estimation of the likelihood of a treatment plant opting for a particular disposal option given the size of the system, whether it is surface water or groundwater, and the type of arsenic removal treatment technology used. 

The Toxicity Characteristic (TC) that identifies wastes as hazardous waste used 100 times the interim primary drinking water standards for eight metals. Although six of the drinking water standards have changed, the TC values have not. However, some people are concerned that after the drinking water MCL is lowered, the TC for arsenic will be lowered to 100 times the new MCL, and that many drinking water treatment residuals will be subject to costly hazardous waste management regulations even though the Office of Solid Waste has stated that the simple 100 times criterion will not be used when the TC regulatory levels are revised, but rather, more sophisticated modeling tools would be used. Consequently, the important questions relating to waste disposal do not relate to hazardous waste disposal. Rather, for brines, they relate to questions such as TDS (total dissolved solids) restrictions in waters receiving brine, and restrictions on sanitary sewer discharge due to TBLLs (technically based local limits). For sludge disposal, they relate to restrictions that may be placed on land application, which may result in more systems using landfills. 

Charge Question 5: Decision tree for ground water treatment technologies—Does the SAB agree with the principal “branches” of EPA's decision tree described in the submitted documents and the likelihood that these options will be used for systems of various sizes with various source water characteristics? What views does the SAB have on EPA's description of the advantages and limitations of these treatment technologies? Would the SAB's views on the these advantages and limitations affect the probabilities assigned? 

EPA has identified treatment technologies that will likely be used to treat arsenic in groundwater systems. These include ion exchange, activated alumina, reverse osmosis, coagulation-assisted microfiltration, greensand filtration, and point-of-use and point-of-entry devices. The EPA has also identified non-treatment options such as regionalization and alternate source. EPA consulted with small utilities and AWWA in order to identify issues which would affect selection of treatment technologies for small systems, which included cost, complexity of operation, chemical handling issues, and frequency of maintenance on point-of-use devices. EPA has assigned selection probabilities to each of these options in a decision tree that form the basis for the Agency's overall cost projections.

                        Availability of Review Materials—Additional information on the materials provided to the Committee for this review can be obtained by contacting Ms. Irene Dooley, US EPA Office of Water by telephone at (202) 260-9531 or by e-mail at                         *dooley.irene@epa.gov.*

# FOR FURTHER INFORMATION CONTACT:

                        Any member of the public wishing further information concerning this meeting or wishing to submit brief oral comments (10 minutes or less) must contact Thomas O. Miller, Designated Federal Officer, Science Advisory Board                               ( print page 30591)                            (1400A), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC 20460; telephone (202) 564-4558; FAX (202) 501-0582; or via e-mail at                         *miller.tom@epa.gov.*                         Requests for oral comments must be in                         *writing*                         (e-mail, fax or mail) and received by Mr. Miller no later than noon Eastern Time on May 30, 2000.                     

## 3. SAB Executive Committee (EC) Teleconference—June 12, 2000 

The Executive Committee (EC) of US EPA's Science Advisory Board will conduct a public teleconference meeting on Monday, June 12, 2000 between the hours of 1 and 3 pm Eastern Daylight Time. The meeting will be coordinated through a conference call connection in Room 6013 in the USEPA, Ariel Rios Building North, 1200 Pennsylvania Avenue, NW, Washington, DC. The public is encouraged to attend the meeting in the conference room noted above. However, the public may also attend through a telephonic link, to the extent that lines are available. Additional instructions about how to participate in the conference call can be obtained by calling Ms. Priscilla Tillery-Gadsen no earlier than one week prior to the meeting (beginning on May 29) at (202) 564-4533, or via e-mail at tillery.priscilla@epa.gov. 

*Purpose of the Meeting*                        —In this meeting, the Executive Committee plans to review reports from some of its Committees/Subcommittee, most likely including the following:                     

                        (a) EC Subcommittee on Data from the Testing of Human Subjects:                         *“Report on Data from the Testing of Human Subjects”*

                        (b) EC Subcommittee on Review of Cancer Guidelines:                         *“Applicability of the Agency's Cancer Risk assessment Guidelines to Children”*

                        (c) Environmental Engineering Committee (EEC):                         *“Commentary on Measures of Environmental Technology Performance.”*

*Availability of Review Materials*                        —Drafts of the reports that will be reviewed at the meeting should be available to the public at the SAB website (http://www.epa.gov/​sab) by close-of-business on May 25, 2000.                     

# FOR FURTHER INFORMATION CONTACT:

                        Any member of the public wishing further information concerning this meeting or wishing to submit brief oral comments must contact Dr. Donald Barnes, Designated Federal Officer, Science Advisory Board (1400A), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC 20460; telephone (202) 564-4533; FAX (202) 501-0323; or via e-mail at                         *barnes.don@epa.gov.*                         Requests for oral comments must be in writing (e-mail preferred) and received by Dr. Barnes no later than noon Eastern Time on June 5, 2000.                     

## Providing Oral or Written Comments at SAB Meetings 

                        It is the policy of the Science Advisory Board to accept written public comments of any length, and to accommodate oral public comments whenever possible. The Science Advisory Board expects that public statements presented at its meetings will not be repetitive of previously submitted oral or written statements.                         *Oral Comments:*                         In general, each individual or group requesting an oral presentation at a face-to-face meeting will be limited to a total time of ten minutes. For teleconference meetings, opportunities for oral comment will usually be limited to no more than three minutes per speaker and no more than fifteen minutes total. Deadlines for getting on the public speaker list for a meeting are given above. Speakers should bring at least 35 copies of their comments and presentation slides for distribution to the reviewers and public at the meeting.                         *Written Comments:*                         Although the SAB accepts written comments until the date of the meeting (unless otherwise stated), written comments should be received in the SAB Staff Office at least one week prior to the meeting date so that the comments may be made available to the committee for their consideration. Comments should be supplied to the appropriate DFO at the address/contact information noted above in the following formats: One hard copy with original signature, and one electronic copy via e-mail (acceptable file format: WordPerfect, Word, or Rich Text files (in IBM-PC/Windows 95/98 format). Those providing written comments and who attend the meeting are also asked to bring 25 copies of their comments for public distribution.                     

*General Information*                        —Additional information concerning the Science Advisory Board, its structure, function, and composition, may be found on the SAB Website (                        *http://www.epa.gov/​sab*) and in The FY1999 Annual Report of the Staff Director which is available from the SAB Publications Staff at (202) 564-4533 or via fax at (202) 501-0256. Committee rosters, draft Agendas and meeting calendars are also located on our website.                     

*Meeting Access*                        —Individuals requiring special accommodation at this meeting, including wheelchair access to the conference room, should contact the DFO at least five business days prior to the meeting so that appropriate arrangements can be made.                     

Dated: May 5, 2000. 

Donald G. Barnes, 

Staff Director, Science Advisory Board. 

[FR Doc. 00-12021 Filed 5-11-00; 8:45 am] 

BILLING CODE 6560-50-P