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HomeMy WebLinkAbout75D - WATER QUALITY REPORT REQUEST FOR _COUNCIL ACTION CITY COUNCIL MEETING DATE: ~ ~ CLERK OF COUNCIL USE ONLY: JULY 6, 2004 TITLE: APPROVED D As Recommended D As Amended D Ordinance on 1st Reading D Ordinance on 2nd Reading D Implementing Resolution D Set Public Hearing For PUBLIC HEARING - REPORT ON WATER QUALITY RELATIVE TO PUBLIC HEALTH GOALS CONTINUED TO FILE NUMBER RECOMMENDED ACTION Receive and file the report on Water Quality relative to Public Health Goals. DISCUSSION _he California Environmental Protection Agency Office of Environmental Health Hazard Assessment establishes Public Health Goals (PHGs) for drinking water contaminants. The PHGs are guidelines and are not requirements for any public water system. PHGs are frequently much lower than the Maximum Contaminant Levels established by the United States Environmental Protection Agency (USEPA). Under provisions of the California Health and Safety Code, the City is required to prepare a special report identifying water quality measurements that have exceeded PHGs (Exhibit 1). For the years 2001, 2002, and 2003, the report shows that Santa Ana's drinking water continues to meet all State of California, Department of Health Services and USEPA drinking water standards set to protect public health. The City's drinking water content of naturally occurring uranium and copper levels exceeded the recommended PHG levels. However, no additional treatment is proposed, as reports conclude that treatment will not be cost effective and will not result in a significant reduction of the contaminants. The report also states that optimized corrosion control is the best available technology to reduce the copper levels. The California Department of Health Services has determined that the City has optimized .corrosion control with our treatment and monitoring procedures. The mplementation of new treatment technologies is therefore not ecommended. 75D-1 Public Hearing - To Public Health July 6, 2004 Page 2 Water Quality Relative Goals State law specifies that and responding to public hearing complies with the a public hearing for the purpose comments on the report be held. State's requirement. of accepting This public ENVIRONMENTAL IMPACT In accordance with the California Environmental Quality Act, recommended action is not considered a CEQA proj ect. Therefore, environmental documentation is required. the no FISCAL IMPACT There is no fiscal impact associated with this action. 12 JGR/TC/RFCA06!Zl/04pubhearingH20qualityhealthgoals 75D-2 8 8 8 EXHIBIT 1 CITY OF SANTA ANA REPORT ON WATER QUALITY RELATIVE TO PUBLIC HEALTH GOALS Background: Provisions of the California Health and Safety Code (Reference No.1) specify that large water utilities prepare a special report by July 1, 2004, if their water quality measurements have exceeded any Public Health Goals (PHGs). PHGs are non-enforceable goals established by the Cal-EP A'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 supplier is to use Maximum Contaminant Level Goals (MCLGs) adopted by the United States Environmental Protection Agency (USEP A). Only constituents which have a California primary drinking water standard and for which either a PHG or MCLG has been set are to be addressed. (Reference No. 2 is a list of all regulated constituents with the MCLs and PHGs or MCLGs). There are a few constituents that are routinely detected in water systems at levels usually well below the drinking water standards for which no PHG nor MCLG has yet been adopted by OEHHA ofUSEPA including Total Trihaomethans. These will be addressed in a future required report after a PHG has been adopted. The law specifies what information is to be provided in the report. (Reference No.1) If a constituent was detected in the City's water supply in 2003 at a level exceeding an applicable PHG or MCLG, this report provides the information required by law. Included is the numerical public health risk associated with the 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 treatment if appropriate and feasible. What Are PHGs? PHGs are set by the California Office of Environmental Hazard Assessment (OEHHA), which is part ofCal-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 (MCLs) 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 federal equivalent to PHGs. Water Quality Data Considered: All of the water quality data collected by our water system between 2001 and 2003 for the purpose of detennining compliance with drinking water standards was considered. This data was all summarized in our 2001, 2002, and 2003 Annual Water Quality Reports, which were mailed to all of our customers. (Reference No.3) 1 75D-3 Guidelines Followed: The Association of California Water Agencies (ACWA) formed a work group, which prepared guidelines for water utilities to use in preparing these required reports. The ACW A guidelines were used in the preparation of this report. Best Available Technology and Cost Estimates: Both the USEPA and CDHS adopt what are known as BATs or Best Available Technology, 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 MCLGs are set lower than the MCL, it is not always possible nor feasible to detennine 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 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 our drinking water sources at levels above PHG. Naturally Occurring Uranium The PHG for Natural Uranium is 0.43 pCi/L. The MCL or drinking water standard for Natural Uranium is 20 pCiIL. We have detected Natural Uranium in 13 of our 20 wells at levels 3.0 to 11.4 pCi/L. The levels detected were below the MCL. The category of health risk associated with Natural Uranium, and the reason that a drinking water standard was adopted for it, is that people who drink water containing Natural Uranium above the MCL throughout their lifetime could experience an increased risk of cancer. The 20 pCi/L MCL established by the CDHS if complied with should have no adverse health effect. The numerical risk for cancer for water containing Uranium at the PHG level of 0.43 pCiIL is one case in ] ,000,000. The large water system BAT for Natural Uranium to lower the levels below the PHG is Ion Exchange. Total water production for all affected wells is 32,446 gallons per minute. Based on the USEPA studies, the initial cost to treat one thousand gallons of water at 80 percent removal efficiency for large water systems ranges from $0.54 to $1.68. The on going cost for the treatment ranges from $0.54 to $0.66 per thousand gallons of water treated. For the City of Santa Ana, the estimated cost to install such treatment systems (Ion Exchange) ranges between $6.45 and $20.0 Million. The cost to operate the treatment facilities will range from $6.45 to $7.9 million per year. The cost to build the treatment facilities would result in an assumed increased cost for each customer of$18.53 to $57.45 in the first year and from $18.50 to $22.70 per customer annually. 2 75D-4 8 8 8 Copper The PHG for copper is 0.17 mglL. There is no MCL for Copper. Instead the 90th percentile value of all samples ITom household taps in the distribution system cannot exceed an Action Level of 1.3 mg/L for copper. The category of health risk for copper is gastrointestinal irritation. Numerical health risk data on copper have not yet been provided by OEHHA, the State agency responsible for providing that information. All of our source water samples for copper in 2003 were less than the PHG. Based on extensive sampling of our distribution system in 2003, our 90th percentile value for copper was 0.3mg/L. Our water system is in full compliance with the Federal and State Lead and Copper Rule. Based on our extensive sampling, it was detennined according to State Regulatory requirements that we meet the Action Levels for copper. Therefore, we are deemed by CDHS to have "Optimized Corrosion Control" for our system. In general, optimizating corrosion control is considered to be the best available technology to deal with corrosion issues and with any lead or copper fmdings. We continue to monitor our water quality parameters that relate to corrosively, such as pH, hardness, alkalinity, and total dissolved solids. Action will be taken 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, and there could be additional water quality issues raised. Therefore, no estimate of cost has been included. Recommendations for Further Action: The drinking water quality of the City of Santa Ana meets all State of California, Department of Health Services and USEP A drinking water standards set to protect the public health. To further reduce the levels of the constituents identified in this report that are already significantly below the health-based Maximum Contaminant Levels established to provide "safe drinking water", an additional costly treatment process would be required. The effectiveness of the treatment process to provide any significant reductions in the constituents' 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. 3 75D-5 75D-6