1. Lead in Drinking Water EPA’s Lead and Copper Rule Rick Rogers, Chief Drinking Water Branch U. S. EPA Region 3 District of Columbia Council of Governments Board of Directors Meeting April 14, 2004

2. Focus of the Lead & Copper Rule Protect public health through corrosion control treatment Reduce lead health risks in the community through drinking water exposure

3. How does lead get to the glass? Dissolved Fraction: –Direct leaching from fresh metal surface –Dissolution of mineral scale Particulate Fraction : –Suspension of mineral scale particles –Suspension of lead particles from solder or pipe wall worsened by partial replacement of lead service lines

4. How Does Corrosion Treatment Work? Insulation mechanism –treatment lays down mineral scale –“insulates” pipe wall from water Corrosivity mechanism –reduce water’s aggressiveness toward metal and mineral pH and other water chemistry adjustments

5. Why no Maximum Contaminant Level? Old MCL was 50 ppb leaving plant Sources of lead are in customer plumbing Water utility authority ends before in- house plumbing begins Lead-bearing components widespread Use treatment technique to lower contaminant level

6. EPA regulates Lead in drinking water under the Lead and Copper Rule Should be called: Corrosion Control Rule Water suppliers must : –optimize treatment to control corrosion in customers’ plumbing treatment effectiveness is measured by lead and copper tap samples –monitor tap water levels of Lead at “worst case” homes –achieve Lead Action Level of 15 ppb

7. EPA’s lead action level Maximum Contaminant Level Goal = 0 Action level - treatment technique trigger level –not an enforceable single sample value –15 ppb at the 90th percentile value no more than 10% of samples may exceed Action Level determined with 100 samples/six months reduced monitoring = 50 samples/year or 50 samples/3years

8. Sample site/sample collection Sample sites are private homes Homeowners collect the samples Sites must have sources of lead –lead service lines or lead solder Sentinel homes used to monitor corrosion control treatment effectiveness

9. If Action Level (15 ppb) is exceeded, water system must: Optimize corrosion control treatment Educate customers about health effects of lead, occurrence in drinking water, actions to reduce exposure Intensify tap water monitoring Initiate Lead Service Line Replacement Program (replace at least 7%/year) –(if corrosion control has already been optimized)