EPA Summary of Radon in Drinking Water Stakeholders' Meeting

The purpose of this meeting was to seek input from interested parties ("stakeholders") on the development of the radon in drinking water regulation. In particular, the meeting sought information and comments regarding (1) major technical issues (e.g., occurrence, treatment technology, analytical methods); (2) implementation issues (e.g., multimedia mitigation program); and (3) preferred opportunities for public involvement. A copy of the meeting agenda and a list of key EPA contacts is found in Attachment A.

The meeting began with an introduction and agenda overview by facilitators James Kohanek (TLI Systems, Inc.) and Paul Locke (Environmental Law Institute). They emphasized that the majority of the meeting would be dedicated to receiving stakeholder input, after brief presentations by staff persons from the Environmental Protection Agency (EPA or the Agency). They also pointed out that background papers and presentation overheads had been prepared and distributed to stakeholders.

Cynthia Dougherty (Director, Office of Ground Water and Drinking Water (OGWDW)) and Mary Smith (Director, Indoor Environments Division, Office of Air and Radiation (OAR)) began by emphasizing that EPA is committed to using an open and transparent process to implement the new Safe Drinking Water Act (SDWA) amendments. Both formal input, through meetings like this one and written comments, as well as informal input, through conversations with EPA staff members, are encouraged. The key people in the Indoor Environments Division are Dave Rowson and Laura Kolb. Sylvia Malm is the team leader for the radon in drinking water rule in the OGWDW. Their telephone numbers and e-mail addresses are contained in Attachment A.

Bill Diamond, Director, Standards and Risk Management Division, OGWDW, discussed the background to the radon rule and current EPA perspectives. He reviewed the development of the 1991 proposed Maximum Contaminant Level (MCL) (300 picocuries per liter (pCi/L)). This MCL corresponds to a risk level of 10^-4, at the top end of the Agency's approach to risk reduction. The Agency estimated that approximately 27,000 mostly small public groundwater systems would be affected at this proposed MCL. Mr. Diamond pointed out that Congress had addressed unresolved disagreements about costs and risks by establishing the provisions of the 1996 SDWA amendments. Mr. Diamond noted that the 1996 SDWA amendments do not change the underlying health-based paradigm for developing drinking water regulations, including radon. The SDWA still requires that the MCL be set as close as possible to the Maximum Contaminant Level Goal (MCLG). The starting point for the rule will continue to be a risk level of 10^-4 to 10^-6. The Agency will conduct more thorough data collection and uncertainty analysis, within the time constraints of the statutory deadlines. The 1996 amendments do give EPA greater flexibility for (1) cost-benefit analysis (with some discretion) and (2) small systems implementation. In addition to the mandates contained in the 1996 amendments, EPA is under a court stipulated deadline (December 6, 2000) to take certain actions with regard to other radionuclides for which MCLs were proposed in 1991.

EPA would like stakeholders to focus discussion on the development of the MCL, the Alternative MCL (AMCL) and the multi-media mitigation program. The Agency will also meet the Small Business Regulatory Enforcement Fairness Act (SBREFA) requirements. The National Academy of Sciences (NAS) is providing an independent review of the risk assessment for radon in drinking water, as documented in previous studies and may undertake a new analysis if viewed as necessary. The NAS will also assess the health risk reduction benefits of mitigating radon in indoor air for EPA's use in developing the proposed multi-media mitigation program. The NAS is scheduled to complete its work in July, 1998.

Mr. Diamond emphasized that the Agency is committed to meeting its deadlines under the SDWA amendments. In order to meet the regulation proposal deadline of August, 1999, the health risk reduction and cost analysis, due February 1999, will have a somewhat abbreviated comment period due to the stakeholder involvement anticipated before its publication. He reiterated that the proposed regulation and the guidelines for multi-media mitigation state programs will be promulgated together. He stated that it is important that the regulation be clear and workable, focus on risk reduction and incorporate Congressional intent.

During the stakeholder input period following Mr. Diamond's talk, several persons asked for clarification of the NAS' role. Mr. Diamond indicated that the NAS will be building on the existing risk assessment and developing new analysis, if viewed as necessary. Consideration will also be given to new risk studies from the scientific community, and exposure information available from states, water suppliers and others. He also noted that EPA's revised cancer risk assessment guidelines will be provided to the NAS for their consideration. EPA will ask the NAS to provide a "usable" document for EPA's regulatory development process. The NAS meetings will be open to the public, although the possibility exists that its executive session will be closed.

Jim Taft, Chief, Targeting and Analysis Branch, Standards and Risk Management Division, OGWDW, discussed the technical foundation for the radon in drinking water regulation.

Regarding analytical methods, Mr. Taft pointed out that an important criterion in selecting a method is that it be a reliable, cost-effective method. The method contained in the 1991 proposed rule has been published in the supplement of the 19th Edition of Standard Methods. EPA is in the process of transferring its Performance Evaluation (PE) program to a third party. The future of the national laboratory certification program is uncertain. The four day time limit (from sample collection to analysis) is based on radon's short half-life and sampling techniques, taking into account the demands placed on laboratories. Special collection vials are necessary to gather samples.

During the stakeholder input period, participants pointed out that EPA has embarked on an Agency-wide effort to streamline its approach to analytical methods and asked how this effort will impact radon in water testing. Mr. Taft acknowledged that streamlining is a cross-cutting issue. At the present time it is not possible to assess its impact on the radon in water analytical procedures. The impact of the probable shift of the performance evaluation (PE) program to a third party is a concern, as is the uncertain future of the national laboratory certification program.

Regarding treatment technology, Mr. Taft stated that the 1991 proposed regulation identified aeration as the Best Available Technology (BAT). Since the 1996 SDWA amendments require EPA to withdraw the radon portion of the 1991 proposed radionuclides in drinking water regulation, the development process for the new proposed radon regulation will include consideration of the radon BAT. The 1996 amendments require EPA to investigate technologies applicable to small systems (such as point-of-entry (POE) devices) as possible compliance treatment technologies. These devices will be examined as compliance technologies for small drinking water systems. Granular activated carbon (GAC) devices might be a better technology for very small systems. However, the use of GAC raises concerns about gamma radiation exposure (as the carbon bed becomes spent), the susceptibility to sudden removal efficiency drop-off, and the proper method of disposal of the used carbon beds, which may contain residual radioactivity.

During the stakeholder input period, participants asked about the disposal of spent GAC. Mr. Bill Labiosa, from EPA's OGWDW, pointed out that it is best to use GAC in situations where it is unlikely to adsorb a great deal of radiation. Stakeholders asked for guidance concerning waste disposal and off-gassing from GAC units. Stakeholders pointed out that at least some states require permits for GAC systems and regulate disposal of associated waste. Stakeholders added that some towns will not permit the dumping of GAC waste if it is radioactive. More research is needed to determine how to remove radiation from the carbon beds and regenerate them. Also, some towns do not allow aeration of water without a permit. EPA should be aware that water treatment facilities in and around residential areas trigger protests and this cost should be factored into the cost-benefit analysis. Stakeholders also mentioned that EPA should be aware that the MCL and other aspects of the regulation are likely to be applied as de facto standards for private wells. It was suggested that EPA specifically address this area and provide guidance for private wells.

Stakeholders expressed concern about co-occurrence. Several mentioned that co-occurrence raises cost estimates considerably, and asked how they could most effectively assist EPA regarding evaluation of this issue. Mr. Taft suggested that stakeholders continue to participate in this process, and also participate in two up-coming meetings: (1) a stakeholders meeting on cost-benefit issues in Washington, D.C. on September 23-24, 1997 and (2) a design workshop for cost-benefit analysis that EPA has scheduled for early November, 1997, in Denver, Colorado. The Denver workshop will be open to the public, but participation will be limited to 25 invitees. It will relate to a number of regulations, including radon in drinking water. Stakeholders also expressed concern about BAT availability and costs for small systems, which may not have the resources and expertise to adopt the BAT. Stakeholders from some states asked EPA to provide flexibility in implementation for small systems. Other stakeholders remarked that treatment technologies for trihalomethane (THM), lead and copper may work at cross-purposes with radon treatment. Stakeholders also asked how to balance affordability issues with issues of population sensitivity. There may be sensitive sub-populations that need protection.

Stakeholders requested additional information about the ambient air standard for radon, and how it related to aeration as the BAT. There is no radon National Ambient Air Quality Standard (NAAQS), although some state and local permitting agencies may have requirements.

Regarding occurrence, Mr. Taft stated that the mean system radon level is 246 pCi/L according to NIRS. NIRS indicated that 27,000 water systems serving 19 million people exceeded the proposed MCL. Smaller systems exceed this mean more often than larger systems. Some commenters on the 1991 proposal were concerned that levels of radon in well water were higher than projected by EPA. Commenters also recommended that EPA should examine higher than average regional levels, temporal variability, point of compliance questions, radon decay, and differences among water systems.

EPA is now updating its occurrence database to assess whether new occurrence data that has become available since 1991 can be included. The Agency expects to complete its update by Spring, 1998. Occurrence and risk characterization information will be used to assess costs and benefits associated with various possible MCLs.

Stakeholders suggested that EPA look at the disparate numbers in the 1991 occurrence data and the EPA Science Advisory Board (SAB) comments. The issue of sensitive subpopulations was raised; EPA noted that it has entered into an agreement with the Centers for Disease Control and Prevention (CDC) regarding the assessment of vulnerable populations. The Agency will be making efforts to use its new paradigm on vulnerable populations to quantify the benefits to such populations, as well as costs of treatment technology. Treatment affordability will be discussed from both a nationwide and state perspective at a stakeholders' meeting on July 22-23, 1997 in Washington, D.C.

Stakeholders discussed among themselves whether there had been any identified subpopulations that were particularly vulnerable to radon. Some stated that no such subpopulations have been identified according to the National Academy of Sciences report on the biological effects of ionizing radiation (BEIR) IV, but that children and other typically sensitive populations should be considered sensitive with regard to radon exposure. Smokers, obviously, are more sensitive to radon exposure in air. BEIR VI will consider sensitive subpopulations in greater detail.

A report and summary of a recent EPA survey on community water systems is now available. The report is made up of two volumes. Volume 1 contains an executive summary and volume 2 contains the detailed report. A copy of the report can be obtained by telephoning (202) 260-2814.

Stakeholders were interested in whether EPA had carried out any analyses of variability in radon levels in water at different times during the day. Work by graduate students at universities in New England indicates that time of day, weather, and day of the week may be linked to sampling variability. Stakeholders also urged EPA to consult widely with persons and organizations that may have occurrence data and to use such data once available. To the extent it is available and has been checked for quality assurance and control, EPA stated that such data will be considered. The Agency will look at arithmetic and geometric means and carry out statistical analyses before reaching a conclusion about which parameters describe the data most precisely. Stakeholders reminded the Agency of the necessity of checking the accuracy and quality of the data available from other sources.

Other stakeholders pointed out that consumer confidence reporting requirements may also dictate that state data be made public and creating such reports may give states an incentive to collect and distribute water quality data useful for occurrence purposes. Timing will be the issue; consumer confidence data will not be available in time for the promulgation of the radon in drinking water regulation. The suggestion was made to factor into the risk calculations the vagaries of sampling and analysis. States do not have ample resources to address small incremental risks, especially given the holding times and sampling protocols.

Stakeholders pointed out that studies in Iowa showed an increase of radon levels from well head to outlet, which was apparently linked to scale formation in pipes. With regard to the problem of scaling, EPA believes that increased radon levels due to scale formation is an isolated problem, found to date only in Iowa. Stakeholders in New Mexico commented that in their state the radon levels at the distribution point can be higher than radon measured at the intake point.

G. Stakeholder Input Regarding Other Issues Associated with the Technical Foundation of the Proposed Radon Drinking Rule

Stakeholders asked how EPA is defining the term "costs" in its analysis. The Agency will be evaluating a number of factors, and will be carrying out sensitivity analyses to determine the most important cost factors. Regarding sampling for compliance, EPA may use an approach similar to the monitoring protocol currently under consideration ("chemical monitoring reform", but would like suggestions about how many samples are needed, and how frequently sampling should be carried out. At least one state stakeholder mentioned that the minimum four-day holding time requirement is difficult to meet because of the size of the state and lack of laboratory facilities, and another suggested suspending the 4-day limit.

Stakeholders asked whether other radionuclides will be regulated, and were told that EPA plans to decide how to address them by December 6, 2000. One stakeholder meeting will be held in the fall of 1997 to discuss radionuclide-related issues. Others may be held but they are not scheduled yet. The Agency has not yet decided whether to monitor lead-210 as a radon decay product.

Dave Rowson, Director, Center for Healthy Buildings, Indoor Environments Division, OAR discussed the multi-media mitigation program.

Mr. Rowson pointed out that the multi-media program laid out by Congress in the 1996 SDWA amendments is new. It will require coordination of the voluntary, technology-based radon in indoor air guidelines with the regulatory, health-based radon in water standard being developed. At present, EPA is focusing on mitigation of homes and radon-resistant new construction as two key ways that states can achieve health benefits for radon in indoor air to meet risk reduction criteria pursuant to the multi-media program. Mr. Rowson asked participants for specific comments regarding the conceptual framework proposed for multi-media programs, as outlined in his presentation overheads and presentation.

Mr. Rowson pointed out that the NAS will provide the key factors for EPA to determine what the AMCL could be by looking at the data on the water-air transfer factor and the national average level of radon in ambient air. Targeted risk reduction will be based on the MCL; approved multi-media programs will need to "make up the difference" between the MCL and AMCL by reducing risks to radon in indoor air through mitigation, radon-resistant construction and, possibly, through other channels. Public water systems (PWSs) in states with approved multi-media programs could then comply with the AMCL. The SDWA requires EPA to approve multi-media mitigation programs that achieve equivalent or greater risk reduction than would be achieved by regulating the public water supply at the MCL level.

In response to questions, Mr. Rowson mentioned that (1) there is good national occurrence data regarding radon in indoor air; and (2) in the coming year, almost all states will have programs for radon in indoor air. Mr. Rowson also mentioned that a wide variety of state activities are implemented in efforts to lower risks associated with radon in indoor air. States that have been most successful have engaged in a long-term, sustained public outreach program that encompasses real estate transactions, the construction of radon-resistant new homes, education of health professionals, and other channels.

Stakeholders said that it is important to remember that the major focus should be upon the source of the radon and source control. Given that 95% of radon exposure comes from air, and not water, EPA should reassess the need to regulate radon in drinking water. EPA pointed out that it can exercise flexibility in developing the level of the regulatory standard in drinking water, but not with regard to whether radon in water itself is regulated.

EPA considers how to factor smoking into health benefits assessments for radon, but according to Mr. Rowson, the multi-media mitigation program will not give states "credit" for anti-smoking campaigns. EPA clarified that the Office of Air and Radiation, Indoor Environments Division, will have the lead in developing the multimedia guidelines, and will work closely with OGWDW in preparing the guidelines. These will be proposed at the same time as the radon in drinking water regulation.

Mr. Rowson asked for input regarding how the "baseline" for risk reduction should be determined for the multi-media programs. In response, stakeholders asked whether current risk reduction programs and on-going efforts will be eligible for multi-media "credit." They also wanted to know what data or information would be used to set the baseline. State programs can change from year to year, noted one participant, depending upon the funding available. How would EPA compare activist states with states that have less aggressive programs? Some stakeholders said that they interpreted the 1996 SDWA amendments so that if states' existing programs already meet the necessary radon reduction levels, no additional efforts are needed. Mr. Rowson noted that there is a difference of interpretation concerning what activities should be considered in the baseline and that EPA will need to address this issue as the multi-media program guidelines are developed. Mr. Rowson noted that EPA's interpretation is that previous risk reduction accomplishments would not count toward the necessary multi-media health benefits.

Other stakeholders wanted to know whether the states' radon in indoor air programs could remain voluntary, given this multi-media program. EPA stated that the SDWA does not address this point. The multi-media program guidelines could specify that states commit to meeting certain goals (e.g., number of homes mitigated, number of new buildings constructed with radon resistant features by a certain time), in order to comply with AMCL, rather than the MCL. Stakeholders asked how states would be treated if these goals were not met. EPA stated that the SDWA amendments indicate that multi-media programs must achieve equivalent risk or greater reduction than would be achieved by meeting the MCL. Under the 1996 SDWA amendments, EPA may approve only programs that are expected to achieve such risk reduction. Without an approved multi-media mitigation program, PWSs would then be required to comply with the MCL. Alternatively, if a multi-media program is approved and then a state (or individual PWS) does not carry out the approved plan, EPA would work with the State to try to correct the problem (the statute directs EPA to notify the State and provide an opportunity for the State to correct the deficiency). Under this scenario, compliance with the MCL, rather than the AMCL would then be required.

In addition to mitigating existing homes and building new homes with radon-resistant features, stakeholders were interested in whether measures such as public education, incentives for radon testing and outreach programs would be treated in a multi-media program. The NAS assessment will be used by EPA to develop guidelines for states of PWSs regarding how to calculate such risk reduction. Stakeholders commented that the methods used to count the risk reduction for both radon in air and water need to be clear and consistent.

Stakeholders raised the issue of equity as a serious concern. One example mentioned was apartment dwellers with high levels of radon in water who would not gain individual health benefits in a multi-media program based on reducing radon levels in single family homes and new buildings. This scenario was described as similar to arguing for the removal of lead from gasoline, versus lead-paint removal from homes. If the multi-media program favors high income, affluent areas, the multi-media program will be inequitable. Some stakeholders suggested that it might be necessary to limit trading among water systems and allow for extensive community input regarding the multi-media program structure. EPA stated that the SDWA only requires the State to achieve equal or greater risk reduction (to what would have been achieved by meeting the MCL) through the multi-media mitigation program, but does not require that the health benefits accrue to the same individuals or communities. EPA stated that they will need to consider this issue as they develop the regulations and guidelines. Some stakeholders suggested that one way to address equity issues is to have a strong system of accountability and transparent, measurable goals to which states must adhere. Stakeholders were also interested to know how a multi-media program would be structured in a state or geographical area where radon in indoor air levels were low. EPA stated that the guidelines would not change for areas with lower radon in indoor air levels, but these areas may be constrained on how much risk reduction they can achieve through multi-media mitigation programs.

Stakeholders noted that the SDWA amendments allow public water systems, under certain circumstances, to develop multi-media programs of their own initiative. They wanted to know how EPA would accommodate such programs and urged the Agency to be flexible. Participants also pointed out, and EPA agreed, that the amount of risk reduction to be achieved (difference between the AMCL and the MCL) is what is needed to be made up in the multi-media mitigation program.

Some stakeholders said the SIRG (State Indoor Radon Grants) program funds, which are tied to activities undertaken pursuant to the Indoor Radon Abatement Act, should be made available for multi-media programs. Stakeholders also commented that in many states, the drinking water and indoor radon programs are in different agencies; these programs currently are not well coordinated, or not coordinated at all. EPA and stakeholders noted that efforts will need to be made to bridge this gap.

After Mr. Rowson concluded his remarks and addressed stakeholder questions, Sylvia Malm, of the OGWDW, lead a discussion of options for continued stakeholder involvement.

To launch the discussion, Ms. Malm noted that there are several options for keeping informed, including the National Drinking Water Hotline (800-426-4791) and EPA's home page at http://www.epa.gov/OGWDW. She also mentioned several options that EPA or others could pursue as opportunities for stakeholder input, including technical advisory groups, stakeholder meetings, focus workshops and others. She posed several questions for discussion: Are there any other issues, in addition to the ones discussed here today, that should be discussed? What should be the goals of the stakeholder process? What participants should be involved and what should be the timing for stakeholder input? Ms. Malm asked participants for feedback about options for involvement and options for information exchange.

The issues for continued discussion that stakeholders identified were: (1) saving lives; (2) meeting the mandates of the statute; (3) achieving the practical implementation of the regulation; (4) making science-based, objective decisions; (5) obtaining "buy-in" from all who will be implementing the rule and guidelines; and (6) impacts on private well owners. Stakeholders felt that buy-in is more likely than consensus. A process should be developed for reconciling differences between public water systems and states with regard to the multi-media program.

Stakeholders commented that it would be valuable for EPA to circulate preliminary drafts at an early stage, so that ample time to comment was available. In particular, BAT and criteria for state multi-media programs should be distributed early. State stakeholders are concerned about resources available for program implementation. Stakeholders were also concerned about the order in which issues would be reviewed.

It was pointed out that risk communication materials will be needed to explain the MCL, AMCL, the multi-media program, and other aspects of the SDWA program implementation. Stakeholders advised EPA to consider layers of participation -- separate out the technical issues, for example, and create a technical panel to address them. This group could produce a "strawman" document for further review. If timing permitted, this technical group could make a presentation to the NAS. Also, outreach should be undertaken for groups that are not now involved, but should be involved. Meetings should be held around the country, as they have been for the ground water disinfection rule.

Stakeholders also asked for a briefing on the NAS proceedings, if feasible given the timing. Dr. Steve Simon, the NAS task manager for risk assessment of radon in drinking water, graciously agreed. Some of the technical issues, such as sampling and analysis, could be addressed now, independently of the NAS.

For keeping informed, participants suggested the use of e-mail (or faxes, for those without e-mail). EPA pointed out that OGWDW home page (URL address: http//www.epa.gov/ogwdw) will provide status reports.

The meeting closed with a brief wrap-up by James Kohanek and Paul Locke, who thanked stakeholders for attending and stated that a copy of this meeting summary would be sent to all participants and other interested parties.

Attachment A

Agenda

RADON IN DRINKING WATER
STAKEHOLDERS' MEETING

To seek input from interested parties ("stakeholders") on development of EPA's radon in drinking water rule, specifically:

a) Major technical issues (e.g., occurrence, treatment technology, analytical methods)

8:30 - 9:00	REGISTRATION
9:00 - 9:15	INTRODUCTIONS AND AGENDA OVERVIEW Facilitators: James Kohanek, Technical & Legal Information Systems Paul Locke, Environmental Law Institute
9:15 - 9:30	OPENING REMARKS Cynthia Dougherty, Director Office of Ground Water & Drinking Water (OGWDW) Mary Smith, Director Indoor Environments Division, Office of Air and Radiation
9:30 - 10:00	OVERVIEW: Background and Current EPA Perspectives Bill Diamond, Director Standards & Risk Management Division, OGWDW 1991 Proposal 1996 SDWA Requirements Deadline Challenges Goals of Stakeholder Involvement NAS Study MCL & Alternative MCL Options Update on Radionuclides Stakeholder Questions
10:00 - 12:00	TECHNICAL FOUNDATION FOR PROPOSED RADON IN DRINKING WATER RULE James Taft, Chief Targeting and Analysis Branch, Standards and Risk Management Division, OGWDW Analytical Methods EPA Background 1991: Liquid scintillation and Lucas cell Response to 1991 comments 1997 plan: Assess other methods, sampling, holding time, and implementation Treatment Technology EPA Background 1991: Aeration selected as BAT Response to 1991 comments 1997 plan: Re-evaluate aeration & GAC taking into account small system affordability Treatment risks & pre/post treatment requirements Occurrence EPA Background 1991: National Inorganics & Radionuclides Survey Proposed Monitoring Schedule Response to 1991 comments 1997 plan: Update occurrence and exposure analyses taking into account available new data Include indoor air comparison and co-occurrence
10:20 - 10:35	BREAK
10:35 - 12:15	STAKEHOLDER INPUT ON TECHNICAL ISSUES
12:15 - 1:15	LUNCH (on your own)
1:15 - 3:15	MULTIMEDIA MITIGATION PROGRAMS: ISSUES FOR GUIDELINES DEVELOPMENT & IMPLEMENTATION David Rowson, Director Center for Healthy Buildings, Indoor Environments Division Office of Radiation & Indoor Air Radon in Indoor Air Health Risks Background on EPA's Radon in Indoor Air Program SDWA Multimedia Mitigation Program Framework Potential Concept for Multimedia Mitigation Program Guidelines Key Issues for Stakeholder Input - For what new risk reduction efforts should states get credit? - How should states measure, document and report results? - How should public water systems be treated if states do/do not have an approved multimedia plan? - What are the barriers and incentives for states and public water systems to implement multimedia programs? - Other key issues?
3:15 - 3:30	BREAK
3:30 - 4:15	OPTIONS FOR CONTINUED STAKEHOLDER INVOLVEMENT Sylvia Malm, OGWDW EPA Background Options for In-Depth Involvement in Key Issues Options for Providing or Receiving Information Stakeholder Input on Options for Continued Involvement
4:15 - 4:30	WRAP UP & NEXT STEPS Facilitators: James Kohanek and Paul Locke

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Summary of Radon in Drinking Water Stakeholders' Meeting

EXECUTIVE SUMMARY

Attachment A

Agenda

RADON IN DRINKING WATER STAKEHOLDERS' MEETING

RADON IN DRINKING WATER
STAKEHOLDERS' MEETING