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HomeMy WebLinkAbout14 Attachment 1 - 2022 Public Health Goals ReportTRUCKEE D• Public Utility District General Manager TRUCKEE DONNER PUBLIC UTILITY DISTRICT Brian C. Wright 2022 PUBLIC HEALTH GOALS REPORT Executive Leadership Team Joe Horvath Electric Utility Director/ Background AGM Chad J. Reed Provisions of the California Health and Safety Code specify that larger (>10,000 Water Utility Director service connections) water utilities prepare a special report by July 1, 2022 if water Shanna Kuhlemier quality measurements have exceeded any Public Health Goals (PHGs). PHGs are non - District Clerk enforceable goals established by the California Environmental Protection Agency's Scott Crow (Cal -EPA) Office of Environmental Health Hazard Assessment (OEHHA). The regulation Chief Information also requires that where OEHHA has not adopted a PHG for a constituent, the water Officer suppliers are to use the Maximum Contaminant Level Goals (MCLG) adopted by the Steven Poncelet PIO & Strategic Affairs United States Environmental Protection Agency (USEPA). Only constituents which Director have a California primary drinking water standard and for which either a PHG or MCLG Michael Salmon has been set are to be addressed. Chief Financial Officer Jillian Steward There are a few constituents that are routinely detected in water systems at Director of Human levels usually well below the drinking water standards for which no PHG nor MCLG Resources and have been adopted by OEHHA or USEPA including Total Trihalomethanes. These will Risk Management be addressed in a future required report after a PHG has been adopted. Board of Directors Joseph Aguera The regulation specifies what information is to be provided in the report. If a Jeff Bener constituent was detected in the Truckee Donner Public Utility District's (TDPUD) water Chrristta Finn Kim Harris supply between 2019 and 2021, at a level exceeding an applicable PHG or MCLG, this Tony Laliotis report provides the information required under the regulation. Included is the numerical public health risk associated with the Maximum Contaminant Level (MCL) and the PHG or MCLG, the category or type of risk to health that could be associated with each constituent, the best treatment technology available that could be used to reduce the constituent level, and an estimate of the cost to install that treatment if it is appropriate and feasible. What Are PHGs? PHGs are set by the California Office of Environmental Health Hazard Assessment (OEHHA) which is part of Cal -EPA and are based solely on public health risk considerations. None of the practical risk -management factors that are considered by the USEPA or the California Department of Health Services (CDHS) in setting drinking water standards are considered in setting the PHGs. These factors include analytical detection capability, treatment technology available, benefits and costs. The PHGs are not enforceable and are not required to be met by any public water system. MCLGs are the federal equivalent to PHGs. PUBIC SPECIAL DISMICT 11570 Donner Pass Road, Truckee, CA 96161 1 (530) 587-3896 1 tdpud.org RCI.E. o� LFJIDEBSNIP FOUNDATION Water Qualitv Data Considered All of the water quality data collected by the TDPUD water utility between 2019 and 2021, for purposes of determining compliance with drinking water standards was considered. This data was all summarized in our 2019, 2020, and 2021 Annual Water Consumer Confidence Reports which were posted on the TDPUD website for customers to review by July 111 of each subsequent year. Guidelines Followed The Association of California Water Agencies (ACWA) formed a workgroup which prepared guidelines for water utilities to use in preparing these newly required reports. The ACWA and California Department of Public Health guidelines were used in the preparation of this report. Best Available Treatment Technology and Cost Estimates Both the USEPA and CDHS adopt what are known as BATS or Best Available Technologies which are the best known methods of reducing contaminant levels to the MCL. Costs can be estimated for such technologies. However, since many PHGs and all MCI -Gs are set much lower than the MCL, it is not always possible nor feasible to determine what treatment is needed to further reduce a constituent downward to or near the PHG or MCLG, many of which are set at or close to zero. Estimating the costs to reduce a constituent to zero is difficult, if not impossible because it is not possible to verify by analytical means that the level has been lowered to zero. In some cases, installing treatment to try and further reduce very low levels of one constituent may have adverse effects on other aspects of water quality. Constituents Detected That Exceed a PHG or a MCLG The following is a discussion of constituents that were detected in one or more of the TDPUD's drinking water sources at levels above the PHG, or if no PHG, above the MCLG. Arsenic: The MCL for arsenic is 10 parts per billion (ppb), the PHG and MCLG for arsenic is 0.004ppb. We have detected arsenic in 6 of our 10 wells, Glenshire Drive Well at 8.9ppb, Martis Valley Well at 9.9ppb, Airport Well at 6.2ppb, Old Greenwood Well at 2.6ppb, Prosser Village Well at 2.7ppb, and Sanders Well at 8.6ppb. It is important to note that the Glenshire Drive Well, Old Greenwood Well and Prosser Village Well are delivered through a California State Water Resources Control Board (SWRCB) approved blending permit maintaining post blend water deliveries with arsenic concentrations below the MCL. The category of health risk associated with arsenic, and the reason that a drinking water standard was adopted for it, is that continuous long term exposures to drinking water containing arsenic levels above the MCL may increase the risk of cancer. The California Office of Environmental Health Hazard Assessment (OEHHA) has set the PHG at 0.004ppb. The PHG is based on a level that will result in not more than 1 excess cancer in 1 million people who drink 2 liters daily of this water for 70 years. The actual cancer risk may be lower or zero. The BAT that we are using for this report to lower the level below the MCL to .004ppb is fixed bed adsorption system. The estimated cost to install and operate such a treatment system on all 6 Wells that would reliably reduce the Arsenic level to .004ppb would be approximately $8,100,000 initial construction cost with additional estimated O&M cost of an $6,900,000 per year. This would result in an assumed increased cost for each customer of approximately $592 per year. RECOMMENDATIONS FOR FURTHER ACTION The drinking water quality of the Truckee Donner Public Utility District at this time meets all California State Water Resources Control Board and USEPA drinking water standards set to protect public health. To further reduce the levels of the constituents identified in this report that are already below the health -based MCLs established to provide "safe drinking water", additional costly treatment processes would be required. The effectiveness of the treatment processes to provide any significant reductions in constituent levels at these already low values is uncertain. The health protection benefits of these further hypothetical reductions are not at all clear and may not be quantifiable. Therefore, no action is proposed. The money that would be required for these additional treatment processes might provide greater public health protection benefits if spent on other water system operation, surveillance, and monitoring programs.