ML20217H774
| ML20217H774 | |
| Person / Time | |
|---|---|
| Issue date: | 03/11/1998 |
| From: | Thompson H NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | Perciasepe R ENVIRONMENTAL PROTECTION AGENCY |
| References | |
| NUDOCS 9804300068 | |
| Download: ML20217H774 (8) | |
Text
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-4 UNITED STATES E
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E NUCLEAR REGULATORY COMMISSION E
E WASHINGTON, D.C. 2055H001 March 11, 1998 Mr. Robert Perciasepe i
Assistant Administrator for Water U.S. Environmental Protection Agency 401 M Street, Southwest Washington, D.C. 20460
Dear Mr. Perciasepe:
i The U.S. Nuclear Regulatory Commission (NRC) has been following the U.S. Environmental
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Protection Agency's (EPA's) recent efforts to revise its drinking water standards for radionuclides. Because of our interest in how these standards may be applied, staff attended your stakeholders' meeting, held on December 11-12,1997, in Arlington, Virginia (noticed in the l
November 7,1997, Federal Reaister). As you are aware, NRC has concerns with EPA's policy
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of linking ground-water protection requirements to its drinking water standards, especially in the l
context that these very low-levels of radiation exposures are needed to protect public health and j
safety. NRC believes that individual protection criteria that uses an all-pathways approach are j
sufficiently protective of the groundwater pathway and represents a more uniform and comprehensive approach to protecting public health and safety, in addition to being consistent with national and international recommendations for radiation protection. Because of the i
importance of a consistent national approach to protection of the public from low levels of radiation, we recommend that these proposed drinking water standards undergo a complete review by EPA's Radiation Advisory Committee of its Science Advisory Board to review the l
differences of opinion regarding both science and policy. To assist the Board in its review, we would request that the comments received from the stakeholders' meeting (including NRC's) be provided to the Committee for its deliberations.
Enclosed are comments basedon our understanding of the draft revisions to the final standards (Enclosure 1). These comments are similar to the written comments provided at the meeting (Enclosure 2). NRC would appreciate your consideration of these comments in developing your standards and formulating a policy on their implementation.
Since ly, L. Thomp
,J e ty Execu D'
or or Regulatory Pr rams i
Enclosures.
l As stated
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cc: Richard Wilson, Acting Assistant Administrator p'g Air and Radiation, EPA Timothy Fields, Acting Assistant Administrator Solid Waste and Emergency Response, EPA g fj 3_
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9804300068 980311 hh h hhh hh PDR ORG EUSEPA PDR
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Mr. Robert P:rciasepe March 11, 1998 Assist nt Administrctor forW t:r U.S. Environm::ntil Protection Agency 401 M Street, Southwest Washington, D.C. 20460
Dear Mr. Perciasepe:
The U.S. Nuclear Regulatory Commission (NRC) has been following the U.S. Environmental Protection Agency's (EPA's) recent efforts to revise its drinking water standards for radionuclides. Because of our interest in how these standards may be applied, staff attended your stakeholders' meeting, held on December 11-12,1997, in Arlington, Virginia (noticed in the November 7,1997, Federal Reaister). As you are aware, NRC has concems with EPA's policy of linking ground-water protection requirements to its drinking water standards, especially in the context that these very low-levels of radiation exposures are needed to protect public health and safety. NRC believes that individual protection criteria that uses an all-pathways approach are sufficiently protective of the groundwater pathway and represents a more uniform and comprehensive approach to protecting public health and safety, in addition to being consistent with national and intemational recommendations for radiation protection. Because of the importance of a consistent national approach to protection of the public from low levels of radiation, we recommend that these proposed drinking water standards undergo a complete review by EPA's Radiation Advisory Committee of its Science Advisory Board to review the differences of opinion regarding both science and policy. To assist the Board in its review, we would request that the comments received from the stakeholders' meeting (including NRC's) be provided to the Committee for its deliberations.
Enclosed are comments based on our understanding of the draft revisions to the final standards (Enclosure 1). These comments are similar to the written comments provided at the meeting (Enclosure 2). NRC would appreciate your consideration of these commena in developing your standards and formulating a policy on their implementation.
Sincerely, OriginalSigned by p.nava oeen ne "UN forOEDOandforthose Hugh L. Thomps Deputy Executive Director highlighted.Please mak for Regulatory Programs remainingdistitutiorL
Enclosures:
As stated g
cc:
Richard Wilson, Acting Assistant Administrator Air and Radiation, EPA g 3 gj/ f gj Timothy Fields, Acting Assistant Administrator Solid Waste and Emergency Response, EPA Additional cc's:
See next page DOCUMENT NAME: S:\\DWM\\PA H LiMXTlE PA_DW.WP D\\ TIC KET: DWM-980015 DISTRIBUTION w/att:
Central File NMSS r/f PAHLr/f DWM r/f & t/f RJohnson KMcConnell SWastler NStablein JHickey NMSS DO r/f JHolonich HThompson CJones, NMSS PUBLIC
- SEE PREVIOUS CONCURRENCE i
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NAME Thaggard/kv KMcConnell EKraus MWeber HNewsome DATE 1/30/98 2/3/98 2/2/98 2/03/98 2/05/98 _
OFC PAHL*
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PEDV NAME MBell JGreeves CPaperiello HT son y
DATE 2/o5/98 2/17/98 2/23/98
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/ /98 OFFICIAL RECORD COPY LSS : YES,_ NOX_
ACNW: YES _ NO _X
s R. Perciasepe cc: Dr. Stephen L. Brown, Chair EPA's Radiation Advisory Committee Dr. K. Jack Kooyoomjiam, Designated Federal Official for the Radiation Advisory Board (1400), EPA l
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U.S. NUCLEAR REGULATORY COMMISSION COMMENTS ON U.S. ENVIRONMENTAL PROTECTION AGENCY DRAFT FINAL DRINKING WATER STANDARDS FOR RADIONUCLIDES
- 1.
SUMMARY
OF DRAFT FINAL STANDARDS On December 11-12,1997, the U.S. Environmental Protection Agency (EPA) held a "Stakeholders' Meeting" in Arlington, Virginia, on revised standards for radionuclides in drinking water (40 CFR Part 141). The purpose of the meeting was to provide information on EPA's approach to revising the standards and to solicit comments from interested parties.
Based on the U.S. Nuclear Regulatory Commission's participation in the stakeholders' meeting, NRC understands that EPA is considering establishing a maximum contaminant level (MCL) for each alpha emitter, based on target risk levels for morbidity (1x10d) and mortality (5x10-5). EPA is also considering maintaining the existing 4 mrem / year dose limit for beta / gamma emitters.
The dose limit would be based on a 4 mrem / year effective dose equivalent, as proposed in 1991, instead of the existing standard which applies to each organ and the whole body. Akin to what EPA is considering regarding alpha emitters, EPA may also replace the 4 mrem / year dose limit for beta-gamma emitters with specific MCLs for each radionuclide. The MCLs would also be based on target risk levels for morbidity and mortality. EPA has interpreted the 1996 Safe Drinking Water Act as requiring MCLs to be set so that the risk level actually achieved under j
the existing MCLs is maintained or reduced. Accordingly, for radionuclides that have a risk level higher than the target risk levels, their MCLs will be set lower than the current MCL. For radionuclides that have a risk level lower than the target risk levels, the MCL will remain the same. For radium, EPA is considering maintaining the current MCL of 5 pCi/L for radium-226 and radium-228 combined. In 1991, EPA had proposed setting a higher MCL of 20 pCi/L each for radium-226 and radium-228. EPA may also establish an MCL for uranium that may be different from the 20 pg/L (30 pCi/L) proposed in 1991.
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- 2. COMMENTS The NRC's interestin these standards is not in the application of the drinking water standard in protecting the Nation's drinking water in public water systems, but rather in the extension of the standards for other purposes, such as ground-water protection and restoration at facilities regulated by the NRC and Agreement States under the Atomic Energy Act of 1954. As reflected in a December 12,1997 letter from Chairman Jackson to Administrator Browner, NRC has previous'y expressed concems about EPA's policy of linking ground-water protection l
requirements to its drinking water MCLs for a vari 3ty of reasons.
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First, MCLs were never developed for the purpose of ground-water protection. Thay were developed to be applied to drinking water from public water systems at the water tap after j
treatment, not directly to ground water in an aquifer. Both the feasibility of drinking water treatment technologies and the cost of treatment are considered in establishing MCLs.
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2-However, ground-water remediation technologies and costs are not considered. Further, application of MCLs directly to ground-water aquifers without consideration of how the ground water will be used could lead to unnecessarily restrictive and burdensome limits being used for ground-water protection. For example, if dilution occurs through pumpage or remediation occurs through natural attenuation, clean-up of a ground water aquifer to a MCL would lead to a l
concentration below the MCL at the water tap. As a result, implementation of MCLs for ground-water protection could lead to an increased cost to the public without a commensurate improvement in protection of public health and safety.
Second, the use of MCLs can lead to inconsistent levels of protection. Because several l
radionuclides could be present in a single drinking water source and each radionuclide could be limited by an individual MCL, the resulting dose and level of protection would be different, depending on the radionuclides present. This is especially germane given that EPA is l
contemplating establishing MCLs for additional radionuclides. In addition, an individual could be i
exposed through additional pathways (e.g., direct exposure and inhalation). The combined l
effects from exposure to all pathways should be considered. The International Commission of Radiological Protection Publication 60 recommends a dose limit for members of the public of 100 mrem / year (1 millisievert) from exposure to radionuclides. NRC dose limits in 10 CFR Part 20 are consistent with this recommendation and are set to allow an adequate margin of safety to account for the possibility of exposure to multiple sources of radiation. Therefore, NRC believes that individual protection criteria (i.e., dose limits), that take into account all pathways, are sufficiently protective of the ground water and represent a more uniform and comprehensive approach to protecting public health and safety. The use of an all-pathways approach to individual protection is also more consistent with recommendations of international and national I
expert bodies. This approach also allows for maintaining and restoring ground water, as well as l
other media, for beneficial use for current and future users.
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3 decommissioning has resulted in licensees being forced to go to extraordinary expense, both in time and dollars, to allow release of sites, without a commensurate improvement in protection of the public health and safety.
l A simple example is the delay in the release of the United Nuclear Corporation's site in Wood River Junction, Rhode Island l
The site met the NRC's requirements for unrestricted release for buildings
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and soilin 1990 At that time, Sr-90 in groundwater was still above the MCL, but well below
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t the concentration that results in a dose of 25 mrem /yr if someone were to consume 2 liters of drinking water a day for 365 days lt took an additional 5 years of natural flushing of the groundwater for
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Sr-90 concentrations to reduce to levels below the MCL; the site was not available for beneficial reuse during this five-year period because it remained under the license l
Delay in releasing the site also consumed valuable resources of the
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regulatory agencies involved and diverted their attention from other health and environmental matters 1
If a 25 mrem /yr all pathway standard had been in place in 1990, the
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license could have been terminated then to allow beneficial use of the site much sooner NRC has observed other sites where remediation of groundwater to attain comp!iance with the MCLs would have been prohibitively expensive and resulted in a minuscule reduction in risk to the public and the environment CONCLUSION 1
NRC believes that the environmental integrity of the nation's drinking water l
needs to be protected; this can be accomplished by limiting radioactive effluents i
from nuclear facilities and by ensuring that these facilities have been properly decommissioned NRC staff believes that EPA should apply the MCLs for drinking water protection i
in public water supplies as intended in the Safe Drinking Water Act 4
f 4
i NRC STAFF COMMENTS FOR EPA'S RADIONUCLIDE STAKEHOLDERS MEETING DECEMBER 11-12,1997 Introductions. NRC staff appreciates the opportunity to participate in this meeting and comment on EPA's strategies for revismg the National Primary Drinking Water Standards for Radionuclides.
The Nuclear Regulatory Commission regulates civilian uses of source, special nuclear, and byproduct material. NRC's mission is to protect the public health and safety, common defense and security, and the environment.
As a regulatory agency, NRC has been required to implement EPA's Sking water standards for radionuclides through our regulatory programs under the Atomic Energy Act. For example, in 1983, EPA imposed the radionuclide drinking water standards as protection and restoration levels for groundwater at uranium mill tailings sites in accordance with 40 CFR Part 192.
In addition, the scientific basis used by EPA in developing the drinking water standards for radionuclides is part of the same information that NRC uses as the basis for our radiation protection requirements in Title 10 of the Code of Federal Regulations.
Consequently, NRC has an interest in any changes that EPA may propose to the drinking water standards for radionuclides.
i NRC only recently received the discussion papers that EPA prepared for this meeting and is continuing to review those papers. The papers raise a number of technically challenging issues that are actively being considered by NRC and other Federal agencies through the Interagency Steering Committee on Radhtion Standards. These issues include such topics as the use of morbidity vs. mortality as the basis for health standards and the expression of standards in terms of risk vs. dose terms. The papers also raise legalissues that deserve additional attention, such as the constraints imposed by the Safe Drinking Water Act Amendments of 1996 on future revisions of EPA's drinking water standards.
NRC did not receive the papers sufficiently early to allow for their thorough review. Consequently, NRC may provide additional comments in the future in respont,e to the Federal Register Notice that announced this meeting or EPA proposals for rulemaking related to the radionuclide drinking water standards.
i NRC's primary interest in the standards is not in the application of the drinking water standards to protect this Nation's drinking water in public water systems, but rather in the extension of the standards for other purposes, such as 1
groundwater protection and restoration.
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EPA has generally applied the radionuclide Maximum Contaminant Levels (MCLs) to determine the adequacy of protection and restoration of groundwater at uranium mill tailings siter, radioactive waste management facilities, and decommissioned nuclear facilities.
The Commission is opposed to the application of MCLs for cleanup of radionuclides in groundwater at sites regulated by NRC or an Agreement State and considers the use of MCLs in such circumstances to be inappropriate for a variety of reasons. These same reasons also suggest that the MCLs should not be used as groundwater protection standards for radioactive waste management facilities, unless they have been appropriately justified.
First, the MCLs were never developed for these purposes. Instead, they were developed to protect the American public by ensuring that the public's drinking water is safe to drink. EPA considers the risk to public health, in addition to the occurrence of radionuclides in drinking water supplies, the feasibility of drinking water treatment technologies, and the cost of treatment is establishing MCLs.
Any proposal by EPA to apply the MCLs for purposes other than drinking water protection under the Safe Drinking Water Act would need to be justified by a thorough consideration of the risks, feasibility, and costs of such an application.
Second, the MCLs do not lead to a consistent radiological dose or risk. The current MCLs are based on International Commission on Radiological Protection Report No. 2, which is over 30 years old. Application of the MCLs result in l
inconsistent lifetime risk levels ranging from less than 1 in one million to almost 1 in one hundred.
Third, the Commission prefers application of "all pathways" standards, such as that recently established in the NRC's rulemaking on radiological criteria for license termination. All pathways standards limit the dose that a person can potentially receive from all pathways, rather than imposing different limits on i
exposures from each pathway.
Because equivalent radiation doses through any exposure pathway would involve equivalent risks to the person exposed, there is no need to impose more rest ictive limits on individual pathways (e.g., ground water).
Use of an all pathways approach results in a more uniform method for protection public health and safety, is more consistent with recommendations of intemational and national expert bodies, and allows greater flexibility.
The result of EPA's use of MCLs as cleanup levels at sites undergoing t