Radon in Drinking Water Proposed Rule- Background and Status by sammyc2007


									 Radon in Drinking Water
     Proposed Rule:
     Background and Status

Presentation for the Workshop on Radon
  Occurrence, Health Risks, and Policy

             October 4, 2006

                  Rebecca Allen
     U.S. Environmental Protection Agency
   Office of Ground Water and Drinking Water
     Background: Radon Health Effects
• Radon (Rn-222) is a colorless and odorless naturally occurring gas

• Well-known human carcinogen since 1940’s: World Health Organization, National
  Cancer Institute, National Academy of Sciences and other national and international

• Well studied and agreed upon science; MCLG of zero
    Well-known linear non-threshold carcinogen; extensive epidemiological and
     biological evidence of human lung cancer risks from residential radon exposure

• Indoor radon (from soil) is second
  leading cause of lung cancer
                                                                               u r
                                                                               t s
• From drinking water: NAS (1999)
                                                         0 0

  estimates 168 fatal cancer cases each year               9
                                                           0       5

                                                a n
                                               S og
• From indoor air: NAS-BEIR VI (1999)           .%
                                                                              r tn

  estimates 15,000 to 22,000 lung
  cancer deaths each year

                 Office of Ground Water and Drinking Water
   Regulating Radon in Drinking Water

• Important opportunity for public health protection
    NAS Report on Radon in Drinking Water (1999)
      • “Risks associated with waterborne radon are large in comparison
        with other regulated contaminants in drinking water”
      • radon in drinking water causes 168 fatal cancers per year in
        absence of regulation; 89% from lung cancer due to inhalation of
        radon released from water, and 11% primarily from stomach
        cancer due to ingestion

    SDWA Regulation                Number of Avoided Cancer Cases/Year
       Final Arsenic                                 21-30
    Final Stage 2 DBP                                 73
         Final LT2                                  20-314
     Proposed Radon                                   62

             Office of Ground Water and Drinking Water
            What is unique about the radon
               proposed framework?
   • Proposed Rule published in Federal Register November 1999
        Statutory deadline for final rule August 2000

   • Based on SDWA and multimedia radon exposure

   • Two regulatory options:
       MCL: 300 pCi/L, based on SDWA MCL and radon-specific
        language. MCL is within EPA’s traditional risk range of 10-4 to 10-6

        Alternative MCL: 4000 pCi/Lwater, based on NAS guidance and
WITH     SDWA direction

         Multimedia Mitigation (MMM) program: highly flexible, least-cost
         and cost-effective, not prescriptive; proposed 4 criteria; viewed as
         enhancement of existing state radon programs

   • Regulation applies to all CWSs using ground water and mixed water

                   Office of Ground Water and Drinking Water
                     Proposed Radon Framework
                          for States & CWSs

                                      Does STATE
                                        want to
                                     develop MMM

                         STATE       YES     NO
  Potential for
      up to
                       Chooses                         STATE             CWS Meets
 5,000 to 7,000        4,000/MMM                      Chooses               300
Lives Saved/Year       Option                            300

             STATE                 CWS                Lives Saved/Year       OR
                                   Meets                                 CWS Meets
             MMM                   4,000                                 4,000 AMCL
                                   AMCL                                   with MMM

                     Office of Ground Water and Drinking Water
    Multimedia Mitigation Program
•        EPA approvable program plans (State or CWS) provide
         information on :
    1.       Public participation that occurred in development of MMM plan

    2.       Quantitative goals set by State that achieve risk reduction from:
              Mitigation of existing homes
              New homes built radon-resistant

    3.       Program strategy in 2 key areas:
              Testing/mitigation of existing homes (outreach and real estate sales
              Construction of radon-resistant homes

    4.       Measure and report results: 2-year reports (used for 5-year
             EPA reviews)
        State/CWS must demonstrate “equal or greater” benefits

               Office of Ground Water and Drinking Water
      How did EPA set the proposed
            MCL for Radon?
• MCLG of zero

• Analyzed relative risk to human health at various levels (100 – 4,000
  pCi/L) and associated benefits

• Adjusted from 100 pCi/L to 300 pCi/L using radon-specific SDWA
    Proposed MCL is within Agency’s risk range of 10-4 to 10-6
    Administrator determination that benefits “justify” costs

• Another key consideration was “spread” between MCL and AMCL;
  relatively low MCL increase incentive for States and/or systems to
  adopt AMCL and MMM option

• An MCL of 4,000 pCi/L obviates need for MMM program under SDWA

           Office of Ground Water and Drinking Water
                       Total National Benefits and Costs at
                              Various Radon Levels
                                      (Proposal Estimates)

            800                                      Benefits
            700                                      Costs
    $ Millions, 1997

$ Millions, 500
   1997     400
                         4,000 2,000 1,000   700    500      300   100
                                     Radon Level (pCi/L)

                          Office of Ground Water and Drinking Water
         Goals for Radon Rule

• For States to choose AMCL/MMM option
    Historically, many States expressed interest in MMM programs
• For States to continue and enhance existing State indoor air radon
• To achieve higher rates of risk reduction

• Considerations underlying MMM program criteria:
    Voluntary for States
    Criteria provide each State flexibility to tailor specific needs
    Not much risk reduction needed from MCL to achieve “equal or
     greater” benefits (compared to 300 MCL)
    Can choose to use non-regulatory and regulatory approaches
    Current indoor air programs reducing risk with approaches outlined
     in SDWA
    MMM builds on and enhances existing radon programs
     (infrastructure, networks, new opportunities)

          Office of Ground Water and Drinking Water
        Key Issues and Stakeholder
       Concerns on the Proposed Rule
• 775 commenters on proposed rule
• MCL and Rule Structure
    State and utility comments mixed, but generally didn’t support
     proposed MCL
    Higher MCLs ranging from 500 to 4,000 pCi/L were suggested
    Inclusion of “smokers” in risk estimates
• State Resource Drain
    Resources needed to implement MMM option
    AMCL/MMM option complex and requires tight coordination
     between air and water programs within State
• Tort Liability
    Concern over “dual” MCL
• Equity
    Appearance of unequal risk reduction to consumers from AMCL
     and MMM
           Office of Ground Water and Drinking Water
     What are some options that EPA can
      consider for the final Radon Rule?
1.       Maintain option outlined in 1999 proposed rule

2.       Set MCL between 300 and 4,000 pCi/L with AMCL/MMM
         alternative available

3.       Set MCL = 4,000 pCi/L AMCL with mandatory MMM
     •     Would require statutory change

4.       Set MCL = 4,000 AMCL with no MMM program
     •     Approximately 4 Lives Saved per year

5.       Other alternatives would require Legislative changes

             Office of Ground Water and Drinking Water
            EPA’s Current Activities on
             Radon in Drinking Water
• January 2009 current projected date for final Radon in Drinking
  Water Rule
• Interim activities and remaining work:
    GAO 2002 analysis of EPA’s cost estimates
    GAO recommendations include:
      • Inclusion of mixed water systems in cost analysis
      • Update off-gas risk estimates and assess impact on cost estimates
      • Expand range of assumptions for estimating compliance costs with
        AMCL/MMM option
    Majority of recommendations have been incorporated;
     remaining await MCL decision

    Competing Drinking Water priorities – Final GWR, recently
     finalized Stage 2 and LT2 rules, CCL 3 process, Lead and
     Copper revisions
            Office of Ground Water and Drinking Water
             Report to Congress:
     Radon in Drinking Water Regulations
•        FY03 Appropriations Language, Congress directed
         EPA to:
    1.     Consult with State drinking water, air, and radiation
           programs, and
    2.     Evaluate options to implement a single drinking water
           standard for radon

        EPA interprets “single drinking water standard” as a
         single MCL for all systems (no MMM)

        EPA consulted with ASDWA and CRCPD in 2003

        Anticipate Final report to be sent to Congress by
         end of 2006

                Office of Ground Water and Drinking Water
              Any Questions?

Rebecca Allen
Office of Ground Water and Drinking Water
U.S. Environmental Protection Agency
(202) 564-4689

       Office of Ground Water and Drinking Water

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