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HomeMy WebLinkAboutResolution No. 07-7000 - Adopt 2007 Water System Report on Public Health GoalsRESOLUTION NO. 07-7000 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DOWNEY ADOPTING THE 2007 CITY OF DOWNEY WATER SYSTEM REPORT ON PUBLIC HEALTH GOALS. WHEREAS, Provisions of the California Health and Safety Code (Section 116470) specify that a public water system serving more than 10,000 service connections must prepare a Public Health Goals Report (Report) by July 1 , 2007 that provides information on the detection of any contaminants in the public water system from 2004 through 2006 that exceed the Public Health Goals (PHGs). WHEREAS, the City is an urban supplier of water providing water to a population of approximately 1 12,000 through approximately 22,500 service connections; and WHEREAS, the City provides over 17,000 acre-feet of water to its customers annualjy; and WHEREAS, Section 116470 requires that the Report be prepared every three years; and WHEREAS, Section 116470 requires that the Report be made available for public inspection and that a public hearing be held prior to adoption of the Report; and WHEREAS, the City has, therefore, prepared and made available for public review, draft copies of the Report, and provided proper notice of the public hearing to be held before the City Council of the City of Downey on July 10, 2007; and WHEREAS, all remarks and suggestions brought to the attention of the City were considered prior to the adoption of the Report. NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF DOWNEY DOES HEREBY RESOLVE AS FOLLOWS: SECTION 1. The 2007 City of Downey Water System Report On Public Health Goals, attached hereto as Exhibit “A“ and incorporated by this reference, is hereby adopted and ordered filed with the City Clerk. SECTION 2. The Public Works Director is hereby authorized and directed to make available to the public copies of the Report no later than 30 days after Council adoption. SECTION 3. That the City Clerk shall certify to the adoption of this Resolution. //// RESOLUTION NO. 07-7000 PAGE TWO APPROVED AND ADOPTED this 10th dw of July, 209 mkaFfIM,IS ATTEST: KATHLEEN L. MIDSTOKKE, City Clerk I HEREBY CERTIFY that the foregoing Resolution was adopted by the City Council of the City of Downey at a regular meeting held on the 10th day of July, 2007, by the following vote, to wit AYES : NOES: ABSENT: ABSTAIN : 5 Council Members: Bayer, Cartozian, Gafin, Guerra, Mayor Trejo 0 Council Member: None 0 Council Member: None 0 Council Member: None V6a£ZaDV.%MM-) KATHLEEN L. MIDSTOKKE, City Clerk RESOLUTION NO. 07-7000 EXHIBIT “A“ ( City of Downey Water System Report On Public Health Goals •• • • • • • • • • EPg Prepared by Utilities Division Department of Public Works City of Downey June 2007 RESOLUTION NO. 07.7000 Report onPublicHmlthGoals Background Provisions of the California Health and Safety Code (Section 116470) specify that a public water system serving more than 10,000 service connections must prepare a brief report by July 1, 2007 that gives information on the “detection“ of any contaminants that exceed the Public Health Goals (PHGs). PHGs are non-enforceable goals established by the California Environmental Protection Agency (Cal-EPA)’s Office of Environmental Health Hazard Assessment (OEHHA). The law also requires that where OEHHA has not adopted a PHG for a constituent, the water suppliers are to use the Maximum Contaminant Level Goals (MCLGs) adopted by the United States Environmental Protection Agency (USEPA). The purpose of the report was to give water customers access to information on levels of contaminants that fall below the enforceable mandatory standards such as Maximum Contaminant Levels (MCLs). Additionally, this requirement intends to provide an idea of Lhc cost to totally eliminate any trace of the contaminant from drinking water without regard to how minimal the risk might be. Drinking Water Standard, PHGs and MCLGs The USEPA and the California Department of Health Services (CDHS or DHS) establish drinking water standards at very conservative levels to provide protection to consumers against all but very low to negligible risks. MCLs are the regulatory definition of what is “safe“. Adopted MCLs are the criteria utilized to ensure that a public water system is in compliance with drinking water standards. Per standard health effects language specified in California Drinking Water Regulations, Title 22, Code of Regulations, drinking water which meets DHS standards is associated with little to no risk and should be considered safe PHGs are set by the OEHH A and are based solely on public health risk considerations. None of the practical risk-management factors that are considered by the USEF'A or the CDHS in setting drinking water standards (MCLs) are considered in setting the MCLGs or PHGs. These factors include analytical detection capability, treatment technology availability, 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. ( Attachment No. 1 is a list of all regulated constituents with their MCLs and PHGs or MCLGs.) PGHs and MCLGs are, or may be set at, very low levels where the health risks are very lou' or, in the case of MCLGs of zero, the health risk is zero. Determinations of health City of Downey Water System 2007 Report On Public Health Goals 1 RESOLUTION NO. 07-7000 ( risk at these low levels are frequently theoretically based on risk assessments with many assumptions and mathematical extrapolations. Many contaminants are considered to be carcinogenic and the USEPA has set the MCLGs at zero, which cannot be measured by the practical available analytical methods. If a constituent was detected in the water supply between 2004 and 2006 at a level above an applicable PHG or MCLG, this report provides the information required by the law. Included is the numerical public health risk associated with the MCL and the PH(J 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 annualized cost of the treatment system is included Water Quality Data Considered All of the water quality data collected from our water system between 2004 and 2006 for purposes of determining compliance with drinking water standards was considered. This data was summarized in our 2004, 2005, and 2006 Annual Water Quality- Reports (Consumer Confidence Report or CCR), which were mailed to all of our customers (see attachment No. 2) before July 1 of the following year. 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 MCLGs are set much lower than the MCL, it is neither 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 zero. Estimating the costs to reduce a constituent to a low PHG level (sometimes to non-detect levels or zero) is difficult, if not impossible and highly speculative because it is not possible to verify by analytical means that the level has been lowered to zero. In some cases, installing treatment facility to try and further reduce very low levels of one constituent may have adverse effects on other aspects of water quality. Therefore, they have limited value and may not warrant significant investment of agency time and money Where appropriate, the best available technology (BAT) available that could be used to reduce the constituent level, and an estimate of the annualized cost to design, install and operate that treatment has been estimated. This annualized cost assumes that the cost will be equally shared by each of the 22,500 service connections in the system. City of Downey Water System 2007 Report On Public Health Goals 2 RESOLUTION NO. 07-7000 Constituents Detected That Exceed a PHG or a MCLG The following are discussions of constituents that were detected in one or more of our drinking water sources at levels above the PHG, or if no PHG, above the MCLG. State or EPA MCL 0.005 0.005 15 5 20 0.01 5% 0.015 1.3 Detection Above PHG or MCLG ND – 0.0008 ND – 0.0042 10 1.8ND ND – 6.9 ND – 0.002 ND 1.5% 0.0064 0.2 + of Well DetectedPararneters/Constituents or 'MCLG, 0.0008 0.00006 '0' l019 n4 0.000004 '0 0.002 0.17 Trichloroethytene -E)-mg/L Tetrachloroethyle©t ! Gross Alpha. 'i/LRadium- 228 Uranium -pCI/L Arsenic-n Coliform (') , Lead-mg/L (Action Level, er-mg/L (Action Level, 2 9 20 7 6 11 System-wide s System-wide RO NA Corrosion Control Trichloroethylene (TCE) and Tetrachtotoethytene (PCE) There are two groundwater wells that have TCE levels above the PHG of 0.0008 mg/L, and nine that have PCE levels above the PHG of 0.00006 mg/L. The two wells that have TC'E levels above the PHG are included in the nine wells that exceed the PCE PHG. The category of health risk associated with TCE and PCE, and the reason that a drinking water standard was adopted for it, is that people who drink water containing TCE or PCE above the MCLs throughout their lifetime could experience an increased risk of getting cancer. Per California Drinking Water Regulation of Section 64468.2, Title 22, California Code of Regulations (CCR), that “Drinking water which meets this standard (the MCLs) is associated with little to none of this risk and should be considered safe with respect to TCE or PCE.“ The BAT to lower the TCE and/or PCE levels below the MCLs is Granular Activated Carbon (GAC). Since the TCE or PCE levels in the subject wells are already below the MCL, GAC with a long empty bed contact time would be required. The estimated cost to install and operate such a treatment system at nine wells that would reliably reduce the TCE and PCE level to below the PHGs would be approximately 86.6 million per year, which includes annualized capital costs and operation and maintenance (O&M) costs. This would result in an annual cost of $294 per year per service connection for the life of the treatment system. City of Downey Water System 2007 Report On Public Health Goals 3 RESOLUTION NO. 07-7000 ( Gross Alpha Gross Alpha has been detected from all 20 groundwater wells in the system. The MCL is 15 pCI/L and the MCLG is zero. The levels detected in our system were below the MCL, but were above the level of the MCLG. The CDHS has determined that gross alpha is a health concern at certain levels of exposure. This radiological constituent is a naturally occurring contaminant in some groundwater and surface water supplies. This constituent has been shown to cause cancer in laboratory animals such as rats and mice when the animals are exposed at high levels over their lifetimes. Constituents that cause cancer in laboratory animals also may increase the risk of cancer in humans who are exposed over long periods of time. CDHS has set the MCL drinking water standard for gross alpha at 15 picoCuries per Liter (pCI/L) to reduce the risk of cancer or other adverse health affects that have been observed in laboratory animals. Uranium Uranium has been detected from six wells. The MCL is 20 pCI/L and the PHG is 0.43 pCI/L. The levels detected in our system were below the MCL at all times, but were above the PHG level. CDHS has determined that uranium is a health concern at certain levels of exposure. This radiological constituent is a naturally occurring contaminant in some groundwater and surface water supplies. Exposure to uranium in drinking water may result in toxic effects to the kidney. This constituent has also been shown to cause cancer in laboratory animals such as rats and mice when the animals are exposed at high levels over their lifetimes. Constituents that cause cancer in laboratory animals also may increase the risk of cancer in humans who are exposed over long periods of time. CDHS has set the MCL drinking water standard for uranium at 20 pCI/L to reduce the risk of cancer or other adverse health affects that have been observed in laboratory animals. Radium Radium-228 has been detected in seven wells. The MCL for total Radium is 5 pCI/L and the PHG for Radium-228 is 0.019 pCI/L. The levels detected in our system were below the MCL at all times, but were above the PHG level. The CDHS has determined that radium is a health concern at certain levels of exposure. This radiological constituent is a naturally occurring contaminant in some groundwater and surface water supplies. This constituent has been shown to cause cancer in laboratory animals such as rats and mice when the animals are exposed at high levels [ City of Downey Water System 2007 Report On Public Health Goals 4 RESOLUTION NO. 07-7000 iover their lifetimes. Constituents that cause cancer in laboratory animals also may increase the risk of cancer in humans who are exposed over long periods of time. The Best Available Technology identified to treat these radiological contaminants (Gross Alpha, Uranium, and Radium) is Reverse Osmosis (RO) treatment. We have determined that the cost to install and operate a RO removal system to treat the groundwater wells in our system in order to meet the PHG levels would be approximately $46 million annually, which includes construction and annual operational cost. This translates into an annual cost of $2,034 per service connection for the life of the treatment system. Arsenic There are eleven wells that have arsenic levels between ND (Non-Detection) and 0.002 mg/L that are below USEP A’s newly adopted MCL drinking water standard of 0.010 mg/L, but above the PHG of 0.000004 mg/L. The PHG is based on the mortality of arsenic-induced lung and urinary bladder cancers observed in epidemiological studies of population in Taiwan, Chile, and Argentina. The risk estimates were based on a low- dose linear extrapolation approach although the mode of carcinogen action is not fully understood. Arsenic is a naturally occurring contaminant in the earth’s crust and is widely distributed throughout the environment including groundwater and surface water supplies. All humans are exposed to microgram quantities of arsenic largely from food and to a lesser degree from drinking water and the air. USEPA has set the drinking water MCL standard for arsenic at 0.010 mg/L to reduce the risk of cancer or other potential adverse health affects \ The Best Available Technology identified to treat arsenic is Reverse Osmosis (RO) treatment. The cost to install and operate a RO removal system to treat the groundwater wells in our system in order to meet the PHG level would be approximately $25 million annually, which includes construction and annual operational cost. This translates into an annual cost of $1,090 per service connection for the life of the treatment system conform Bacteria The MCL for coliform is 5% positive samples of all samples taken in a month. The MCLG is zero positive samples. The reason for the coliform drinking water standard is to minimize the possibility of the water containing pathogens, which are organisms that cause waterborne disease. Because coliform is only a surrogate indicator of the potential presence of pathogens, it is not possible to state a specific numerical health risk. conform bacteria are indicator organisms that are ubiquitous in nature and are not generally considered harmful. They are used because of the ease in monitoring and \ City of Downey Water System 2007 Report On Public Health Goals 5 RESOLUTION NO. 07-7000 analysis. If a positive sample is found, it indicates a potential problem that needs to be investigated. It is not at all unusual for a system to have an occasional positive sample. It is difficult, if not impossible to assure that a system will never get a positive sample. Per the Total conform Rule, the City collects a total of 25 coliform samples weekly throughout the distribution system. During the three-year period of 2004 through 2006, there was only one month where positive samples were observed. In the month of June 2004, of the 125 samples taken from the distribution system, two of them were positive. - Three conformation samples were then collected for each of the positive samples, and all six of the confirmation samples were negative. The monthly percentage of positive samples was 1.5%, which is below the MCL of 5% but above the MCLG of zero. We have implemented, and will continue to utilize the best available technologies by CDHS in Section 64447, Title 22, California Code of Regulation. to prevent any microbiological contamination. These include protection of wells by appropriate construction and maintenahce activities, proper preventative maintenance of the distribution system such as flushing, an effective cross-connection control program, an effective monitoring and surveillance program and maintaining positive pressures throughout our distribution system. [ Lead and Copper There is no MCL for lead or copper. Instead, the 90th percentile value of all samples collected from household taps in the service area cannot exceed an Action Level of 0.015 mg/L for lead and 1.3 mg/L for copper. The PHG for lead is 0.002 mg/L. The PHG for copper is 0.17 mg/L. The category of health risk for lead is damage to the kidneys or nervous system of humans. The category of health risk for copper is gastrointestinal rrrrtatlon. Based on extensive sampling of our distribution system, our 90th percentile value for lead was 0.0064 mg/L and 0.2 mg/L for copper. Our water system is in full compliance with the Lead and Copper Rule. Therefore, we are deemed by CDHS to have “optimized corrosion control“ for our system. In general, optimizing corrosion control is considered to be the best available technology to deal with corrosion issues and any lead or copper findings. We continue to monitor our water quality parameters that relate to corrosivity, such as the pH, hardness, alkalinity, and total dissolved solids, and will take action, if necessary, to maintain our system in an “optimized corrosion control” condition. Since we are meeting the “optimized corrosion control“ requirements, it is not prudent to initiate additional corrosion control treatment as it involves the addition of other chemicals into the distribution system, which could result in other water quality issues. Therefore, no estimate of cost has been included. City of Downey Water System 2007 Report On Public Health Goals 6 RESOLUTION NO. 07-7000 Recommendations For Further Action The drinking water quality of the City of Downey Water System meets all CDHS and USEPA drinking water standards set to protect public health. Additional costly treatment processes would be required to further reduce the levels of the constituents identified in this report, which are already significantly below the MCLs established to provide “safe drinking water”. The costs associated with the Best Available Treatment Technology are rough estimates for capital equipment installation and operational expenditures. Other associated costs, such as land acquisition to meet facility space requirement, is not included. The effectiveness of the treatment processes to provide 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. Attachments 1. Table of Regulated Constituents with MCLs, PHGs or MCLGs 2, Water Quality Reports for 2004, 2005 and 2006 City of Downey Water System 2007 Report On Public Health Goals 7