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HomeMy WebLinkAbout19 Water Quality RegulationsTo: From: Date: Subject: enda Item # 19 Board of Directors Brian Wright May 04, 2016 Review of Water Quality Regulations Associated with Lead, Copper and Radon 1. WHY THIS MATTER IS BEFORE THE BOARD This workshop is to review Federal and State drinking water regulations related to the Lead and Copper Monitoring Rule and the monitoring of radiological contaminants found in groundwater. 2. HISTORY The Truckee Donner Public Utility District delivers drinking water to roughly 13,000 customer service connections throughout the Town of Truckee, the community of Hirschdale, and some of the adjacent unincorporated areas. The District utilizes local groundwater resources, pumped from 12 strategically located deep groundwater wells, in meeting the service area's daily and summer peak demands. In addition to the maintenance and operation of the wells, the District maintains compliance with state and federal drinking water regulations through regularly scheduled groundwater monitoring and sampling plans. Included in the District's water quality monitoring plan are the water quality sampling requirements prescribed under the EPA's Lead and Copper Monitoring Rule (LCMR), and the State's gross -alpha particle and radionuclide testing. 3. NEW INFORMATION The Lead and Copper Monitoring Rule I was established by the U.S. Environmental Protection Agency (EPA) in 1991 with the goal of reducing exposures to harmful levels of lead (Pb) and copper (Cu). According to the EPA, lead has been known to cause damage to the brain, red blood cells and the kidney, especially in children and pregnant women. Copper has been known to cause stomach and intestinal distress, liver and kidney damage, and complications of Wilson Is disease in genetically predisposed individuals. The current MCL for lead (Pb) is .015 mg/L, and for copper is 1.3 mg/L. Sources of lead and copper contamination in public drinking water systems can be traced back to lead service lateral pipe materials, as well as residential plumbing that contains copper with lead based solder. Leaching of lead and copper from residential plumbing into drinking water is enhanced by the corrosive properties of the water, if not properly managed. The TDPUD water distribution system does not contain lead water service laterals that the District's staff is aware of. The LCMR initial sampling requirements call for lead an copper testing to be completed every six months. Once compliance has been established, the sampling requirements are reduced to every three years. The last sampling period for the Truckee Main System was in 2013, where all 30 of the District's sampling locations tested "non -detect" for lead and copper. The next round of sampling will take place in the Summer of 2016. The last round of sampling for the Hirschdale System was in 2015, where all five sample locations tested "non -detect" for lead and copper. The Radionuclide Rule was established by the EPA in 2000 in an effort to reduce exposures to naturally occurring radionuclides in drinking water and the risk of cancer. The rule establishes MCLs for combined radium-226 and radium 228, gross alpha particle radioactivity, and beta particle and photon activity. The California Department of Public Health (CDPH) and the State Water Resources Control Board (SWRCB) had previously set MCLs for uranium, strontium, radium, gross -alpha and gross -beta particle activity, as well as tritium. In the State of California, the Constituents of Concern (COC), for gross -alpha and radiological testing of groundwater are uranium, radon, tritium, strontium and gross - alpha particle activity. Here is an overview of the key points regarding radiological compliance with potable groundwater sources: • In the State of California, the Constituents of Concern (COC) for radionuclides include: uranium, radon, tritium, strontium, gross -alpha and gross -beta; • Alpha particles are a type of radiation emitted by some radionuclides. Uranium-238, radium-226, and radon-222 are examples of alpha particle emitters; • The MCL for gross -alpha particle activity has been set at 15pCi/L by the EPA and adopted by the SWRCB; • The MCL for Radium (combined) has been set at 5pCi/L by the EPA and a detectable reporting limit (DLR) has been set at 1 pCi/L by the SWRCB; • Radon is a naturally occurring gas, and is a product of uranium decay. Radon occurs in groundwater and easily transfers to the atmosphere. A radon concentration of 10,000pCi/L in water converts to approximately 1pCi/L in air. Radon is naturally present in environments where uranium and radium concentrations in geologic materials are high, and tends to be abundant in granitic terrains and certain types of sedimentary deposits; • In the State of California there currently is no regulatory requirement for monitoring of radon in drinking water. The EPA has established an "Advisory MCL" for radon at 4,000pCi/L and the SWRCB has established a DLR at 100pCi/L; and • All of the groundwater source wells within the TDPUD water utility are either well below the DLR or "non -detect" for all radium and gross -alpha water quality reporting standards. 4. FISCAL IMPACT This workshop item has no direct fiscal impact. Funding for water quality compliance testing in accordance with the Lead and Copper Rule, and the Radionuclide Rule are included in the Board approved FY16-17 Water Operations Budget. 5. RECOMMENDATION Receive this report and provide staff with any additional feedback. Michael D. Holley General Manager / Water Utility Manager