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HomeMy WebLinkAbout75C - PH - WATER QUALITY RPTREQUEST FOR COUNCIL ACTION CITY COUNCIL MEETING DATE: CLERK OF COUNCIL USE ONLY: JULY 16, 2019 TITLE: APPROVED PUBLIC HEARING — REPORT ON ❑ As Recommended WATER QUALITY RELATIVE TO ❑ Or Amended ❑ Ordinance on 9s' Reading PUBLIC HEALTH GOALS ❑ Ordinance on 2^a Reading (STRATEGIC PLAN NO. 5, 6) ❑ Implementing Resolution ❑ Set Public Hearing For CONTINUED TO FILE NUMBER CITY M AGER RECOMMENDED ACTION Receive and file the report on Water Quality Relative to Public Health Goals. DISCUSSION The 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 (MCLs) 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 every three years identifying water quality measurements that have exceeded PHGs (Exhibit 1). For the years of 2016, 2017, and 2018, the report depicts 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 (Exhibit 2). While the City's drinking water content of naturally occurring uranium, arsenic, perchlorate, and hexavalent chromium levels exceeded the recommended PHG levels (Exhibit 3), the report finds that for these naturally occurring elements, additional treatment would be very expensive, marginally effective, and would not result in significant reduction of the contaminants; therefore, no action is proposed. State law specifies that a public hearing be held for the purpose of accepting and responding to public comments on the report. This public hearing meets the legal requirement. STRATEGIC PLAN ALIGNMENT Approval of this item supports the City's efforts to meet Goal #5 - Community Health, Livability, Engagement & Sustainability, Objective #6 (focus projects and programs on improving the health and wellness of all residents). 75C-1 Public Hearing — Report on Water Quality Relative to Public Health Goals July 16, 2019 Page 2 ENVIRONMENTAL IMPACT There is no environmental impact associated with this action. FISCAL IMPACT is no fiscal impact associated with this action a Fuad Execute Director Public qorks Agency FS/NS/RR Exhibits: 1. City of Santa Ana Report on Water Quality Relative to Public Health Goals 2. California Health and Safety Code § 116470 3. Listing of all Regulated Constituents with MCLs and PHGs or MCI -Gs 75C-2 EXHIBIT 1 JUNE 2019 861 Village Oaks Drive, Suite 100 -Covina, California 91724 Phone: (626) 967-6202 • Fax: (626)331.7065 • Website:www.stetsonengineers.com Northern California Southern California < Arizona • Colorado * Oregon 75C-3 2019 Public Health Goals (PHGs) Report City of Santa Ana 1.0 Introduction Under the Calderon -Sher Safe Drinking Water Act of 1996 public water systems in California serving greater than 10,000 service connections must prepare a report containing information on 1) detection of any contaminant in drinking water at a level exceeding a Public Health Goal (PHG), 2) estimate of costs to remove detected contaminants to below the PHG using Best Available Technology (BAT), and 3) health risks for each contaminant exceeding a PHG. This report must be made available to the public every three years. The initial report was due on July 1, 1998, and subsequent reports are due every three years thereafter. This report has been prepared to address the requirements set forth in Section 116470 of the California Health and Safety Code. It is based on water quality analyses during calendar years 2016, 2017, and 2018 or, if certain analyses were not performed during those years, the most recent data available. The report has been designed to be as informative as possible, without unnecessary duplication of information contained in the Consumer Confidence Reports, which are mailed to customers by July 1st of each year. There are no regulations explaining requirements for the preparation of PHGs reports. A workgroup of the Association of California Water Agencies (ACWA) Water Quality Committee has prepared suggested guidelines for water utilities to use in preparing PHGs reports. The ACWA guidelines were used in the preparation of this 2019 report. These guidelines include tables of cost estimates for BAT. The State of California (State) provides ACWA with numerical health risks and category of health risk information for contaminants with PHGs. This health risk information is appended to the ACWA guidelines. City of Santa Ana 1 2019 PHGs Report 75C-4 2.0 California Drinking Water Regulatory Process California Health and Safety Code Section 116365 requires the State to develop a PHG for every contaminant with a primary drinking water standard or for any contaminant the State is proposing to regulate with a primary drinking water standard. A PHG is the level of a contaminant in drinking water that poses no significant health risk if consumed for a lifetime. The process of establishing a PHG is a risk assessment based strictly on human health considerations. PHGs are recommended targets and are not required to be met by any public water system. The State office designated to develop PHGs is the California Environmental Protection Agency's Office of Environmental Health Hazard Assessment (OEHHA). The PHG is then forwarded to the State Water Resources Control Board, Division of Drinking Water (DDW) for use in revising or developing a Maximum Contaminant Level (MCL) in drinking water. The MCL is the highest level of a contaminant that is allowed in drinking water. California MCLs cannot be less stringent than federal MCLs and must be as close as is technically and economically feasible to the PHGs. DDW is required to take treatment technologies and cost of compliance into account when setting an MCL. Each MCL is reviewed at least once every five years. Total chromium and two radiological contaminants (gross alpha particle and gross beta particle) have MCLs but do not yet have designated PHGs. For these contaminants, the Maximum Contaminant Level Goal (MCLG), the federal U.S. Environmental Protection Agency (USEPA) equivalent of PHGs, is used in the 2019 PHGs Report. N-nitrosodimethylamine (NDMA) has a PHG of 3 nanograms per liter, but is not regulated in drinking water with a primary drinking water standard. Bromodichloromethane, bromoform, and dichloroacetic acid are three disinfection byproducts that have federal MCI -Gs of 0 but are not individually regulated with primary drinking water standards. According to the ACWA guidance and instructions from City of Santa Ana 2 2019 PHGs Report 75C-5 DDW, these four chemicals do not have to be included in the 2019 PHGs Report because they do not have an existing MCL. 3.0 Identification of Contaminants Section 116470(b)(1) of the Health and Safety Code requires public water systems serving more than 10,000 service connections to identify each contaminant detected in drinking water that exceeded the applicable PHG. Section 116470(f) requires the MCLG to be used for comparison if there is no applicable PHG. The City of Santa Ana (City) water system has approximately 44,838 service connections. The following constituents were detected at one or more locations within the drinking water system at levels that exceeded the applicable PHGs or MCLGs: • Arsenic — naturally -occurring in local groundwater • Bromate — formed when naturally -occurring bromide reacts with ozone during the disinfection process. • Coliform Bacteria, Total — naturally -occurring in the environment but can also be an indicator of the presence of other pathogenic organisms originating from sewage, livestock or other wildlife. • Perchlorate — industrial contamination in groundwater • Gross alpha particle activity (gross alpha) — naturally -occurring in local groundwater and surface water purchased from MWDSC • Gross beta particle activity (gross beta) — naturally -occurring in surface water purchased from MWDSC • Uranium — naturally -occurring in local groundwater and in surface water purchased from MWDSC. The accompanying chart shows the applicable PHG or MCLG and MCL for each contaminant identified above. The chart includes the maximum, minimum, and average City of Santa Ana 3 2019 PHGs Report 75C-6 concentrations of each contaminant in drinking water supplied by the City in calendar years 2016 through 2018. 4.0 Numerical Public Health Risks Section 116470(b)(2) of the Health and Safety Code requires disclosure of the numerical public health risk, determined by OEHHA, associated with the MCLs, Action Levels, PHGs and MCLGs. Available numerical health risks developed by OEHHA for the contaminants identified above are shown on the accompany chart. Only numerical risks associated with cancer -causing chemicals have been quantified by OEHHA. Arsenic — OEHHA has determined the health risk associated with the PHG is 1 excess case of cancer in a million people. USEPA has determined the risk associated with the MCL is 2.5 excess cases of cancer in 1,000 people exposed over a 70-year lifetime. Bromate — OEHHA has determined the theoretical health risk associated with the PHG is 1 excess case of cancer in a million people. USEPA has determined the risk associated with the MCL is 1 excess cases of cancer in 10,000 people exposed over a 70-year lifetime. Coliform Bacteria, Total — OEHHA has not established a PHG. USEPA has established an MCLG of 0. Gross Alpha — OEHHA has not established a PHG. USEPA has established an MCLG of 0 and the risk associated with the MCL is 1 excess case of cancer in 1,000 people over a lifetime exposure. Gross Beta — OEHHA has not established a PHG. USEPA has established an MCLG of 0 and the risk associated with the MCL is 2 excess cases of cancer in 1,000 people over a lifetime exposure. City of Santa Ana 4 2019 PHGs Report 75C-7 Perchlorate — OEHHA has not established a numerical health risk for perchlorate because PHGs for non -carcinogenic chemicals in drinking water are set at a concentration at which no known or anticipated adverse health risks will occur, with an adequate margin of safety. Uranium — OEHHA has determined the theoretical health risk associated with the PHG is 1 excess case of cancer in a million people. USEPA has determined the risk associated with the MCL is 5 excess cases of cancer in 100,000 people exposed over a 70-year lifetime. 5.0 Identification of Risk Categories Section 116470(b)(3) of the Health and Safety Code requires identification of the category of risk to public health associated with exposure to the contaminant in drinking water, including a brief, plainly worded description of those terms. The risk categories and definitions for the contaminants identified above are shown on the accompanying chart. 6.0 Description of Best Available Technology Section 116470(b)(4) of the Health and Safety Code requires a description of the best available technology , if any is available on a commercial basis, to remove or reduce the concentrations of the contaminants identified above. The BATS are shown on the accompanying chart. 7.0 Costs of Using Best Available Technologies and Intended Actions Section 116470(b)(5) of the Health and Safety Code requires an estimate of the aggregate cost and cost per customer of utilizing the BATs identified to reduce the concentration of a contaminant to a level at or below the PHG or MCLG. In addition, Section 116470(b)(6) requires a brief description of any actions the water purveyor City of Santa Ana 5 2019 PHGs Report 75C-8 intends to take to reduce the concentration of the contaminant and the basis for that decision. Arsenic — The BATs for removal of arsenic in water for large water systems are: activated alumina, coagulation/filtration, electrodialysis, ion exchange, lime softening, oxidation/filtration, and reverse osmosis. Arsenic was detected above the PHG in the local groundwater (Wells 37 and 38). The City is in compliance with the MCL for arsenic. The estimated cost to reduce arsenic levels in local groundwater to below the PHG of 0.004 microgram per liter (tag/1) using ion exchange was calculated. Because the DDW detection limit for purposes of reporting (DLR) for arsenic is 2 tag/I, treating arsenic to below the PHG level means treating arsenic to below the DLR of 2 tag/l. There are numerous factors that may influence the actual cost of reducing arsenic levels to the PHG. Achieving the water quality goal for arsenic could be approximately $1,500,000 per year, or $32 per household per year. Bromate — The BATs for removal of bromate in water for large water systems are: coagulation/filtration optimization, granular activated carbon, and reverse osmosis. Bromate was detected above the PHG in surface water supplied by MWDSC. The City is in compliance with the MCL for bromate. The estimated cost to reduce bromate levels in MWDSC surface water to below the PHG of 0.1 pg/l using reverse osmosis was calculated. Because the DDW detection limit for purposes of reporting (DLR) for bromate is 1 tag/l, treating bromate to below the PHG level means treating bromate to below the DLR of 1 tag/l. There are numerous factors that may influence the actual cost of reducing bromate levels to the PHG. Achieving the water quality goal for bromate could range from approximately $2,610,000 to $22,230,000 per year, or between $58 and $496 per household per year. Coliform Bacteria, Total — The BAT for removal of coliform bacteria in drinking water has been determined by USEPA to be disinfection. The City already disinfects all water served to the public. Chlorine or chloramines is used to disinfect the water because it is City of Santa Ana 6 2019 PHGs Report 75C-9 an effective disinfectant and residual concentrations can be maintained to guard against biological contamination in the water distribution system. Coliform bacteria are indicator organisms that are ubiquitous in nature. They are a useful tool because of the ease in monitoring and analysis. The City collects weekly samples for total coliforms at various locations in the distribution system and monthly at each well. If coliform bacteria are detected in the drinking water sample, it indicates a potential problem that needs to be investigated and followed up with additional sampling. It is not unusual for a system to have an occasional positive sample. Although USEPA set the MCLG for total coliforms at 0 percent positive, there is no commercially available technology that will guarantee 0 percent positive every single month; therefore, the cost of achieving the PHG cannot be estimated. The City will continue several programs that are in place to prevent contamination of the water supply with microorganisms. These include: Disinfection using chlorine or chloramines and maintenance of a chlorine residual at every point in the distribution system Monitoring throughout the distribution system to verify the absence of total coliform and the presence of a protective chlorine residual • Flushing program in which water pipelines known to have little use are flushed to remove stagnant water and bring in fresh water with residual disinfectant • Cross -connection control program that prevents the accidental entry of non - disinfected water into the drinking water system. Gross Alpha, Gross Beta, and Uranium — The only BAT for the removal of gross alpha in water for large water systems is reverse osmosis, which can also remove gross beta, and uranium, if detected. Gross alpha was detected above the MCLG in the local groundwater and in the surface water supplied by MWDSC. Gross beta was detected above the MCLG in the surface water supplied by MWDSC. Uranium was detected above the PHG in the local groundwater (Wells 16, 18, 20, 21, 24, 27, 28, 29, 30, 33, City of Santa Ana 7 2019 PHGs Report 75C-10 34, 35, 36, 37, 38, 39, and 41) and in the surface water supplied by MWDSC. The cost of providing treatment using reverse osmosis to reduce gross alpha levels in local groundwater and in MWDSC surface water to the MCLG of 0 picoCurie per liter (pCi/1) (and consequently gross beta in MWDSC surface water below the MCLG; and uranium in local groundwater and in MWDSC surface water below the PHG) was calculated. Because the DLR for gross alpha is 3 pCi/l, treating gross alpha to 0 pCi/I means treating it to below the DLR of 3 pCi/I. Achieving the water quality goal for gross alpha could range from $8,690,000 to $74,100,000 per year, or between $194 and $1,651 per household per year. Perchlorate — The BATS for removal of perchlorate in water are: ion exchange and biological fluidized bed reactor. Perchlorate was detected above the PHG in the local groundwater (Well 24). The City is in compliance with the MCL for perchlorate. The estimated cost to reduce perchlorate levels in local groundwater to below the PHG of 1 pg/I using ion exchange was calculated. Because the DLR for perchlorate is 4 pg/I, treating perchlorate to below the PHG level means treating perchlorate to below the DLR of 4 lag/l. There are numerous factors that may influence the actual cost of reducing perchlorate levels to the PHG. Achieving the water quality goal for perchlorate could range from $105,000 to $226,000 per year, or between $2.33 and $5.04 per household per year. All Contaminants — In addition, a cost estimate to treat all water produced or purchased by the City using ion exchange and reverse osmosis to remove all the contaminants detected above the PHGs or MCLGs was calculated. All the contaminants listed in the accompanying chart may be removed to non -detectable levels by ion exchange and reverse osmosis, except total coliform bacteria. As shown on the accompanying chart, achieving the water quality goals for all contaminants, except total coliform bacteria, using ion exchange and reverse osmosis could range from $8,800,000 to $74,300,000 per year, or between $196 and $1,657 per household per year. City of Santa Ana 8 2019 PHGs Report 75C-11 For additional information, please contact Mr. Robert Hernandez, Water Services Quality Supervisor, at (714) 647-3341, or write to the City of Santa Ana, 220 South Daisy Avenue, Santa Ana, California 92703. City of Santa Ana 2019 PHGs Report 75C-12 wo 9 S Uia V wN �' V C v ,Ua o g a «� rc 0 LL O W 3° ° y° K m K W w w aU LU Li W V b b b N a a .o- a C'h N u a ry r N N p y y W 6 f Z x y p o x I 140 U K Ufa Z U U w U U U I F MO U U N a j z z o c N z 3 zo U a OWE Z N Z Z N m ONE w ul z m Z Z Z v Z v Z m U> 0 Z N e m a UKJ a0f e p I p w w Elm e = E Qy W �n E e K J c U U' a FF U W J C z2_ ° 2 a € ° 4 U a n m a 8 v' Ko u m o 0¢ m E U o e ° o o m u o Er z¢`ma U`ci5 w m � 0 o v° z � a U= ro ° Eyy`� 6'ctlb iE E2 mcE Oam'F°v c'rvc� v 3' ooc SEU m F �jp U;m�OW OxK Bi �II II F WASH III 4D < II II 11 OK 3 8 9 2 E Y '5 �v 5 Eo 5 � yv �i YyL' E 8W - E _ � � m d E vat 8 � _ $ I 3 E� E ° NW j �D v f 9 wmcEa �F 0 K E „la. "C Nja a G E 11gaa s s� e� EaEeEm v. g E ES aao mEE6.p�na.E€ �nH9P o'er o .,F i E.6 iwi .=Eccy L°°c 883 5 tai .6 v° yMANUiEao0 jjQQ��EEE E U yU_W F'U'JJ^II I ",Hq 11MMWwa � sa�9zzzImy JV— IQ 75C-14 "n I IAfE OF CALI FORK IA - ;'- AUTHENTICATED t..� ELECTRONIC LEGAL MATERIAL ". State of California HEALTH AND SAFETY CODE Section 116470 EXHIBIT 2 116470. (a) Asa condition of its operating permit, every public water system shall annually prepare a consumer confidence report and mail or deliver a copy of that report to each customer, other than an occupant, as defined in Section 799.28 of the Civil Code, of a recreational vehicle park. A public water system in a recreational vehicle park with occupants as defined in Section 799.28 of the Civil Code shall prominently display on a bulletin board at the entrance to or in the office of the park, and make available upon request, a copy of the report. The report shall include all of the following information: (1) The source of the water purveyed by the public water system. (2) A brief and plainly worded definition of the terms "maximum contaminant level," "primary drinking water standard," and "public health goal:' (3) If any regulated contaminant is detected in public drinking water supplied by the system during the past year, the report shall include all of the following information: (A) The level of the contaminant found in the drinking water, and the corresponding public health goal and primary drinking water standard for that contaminant. (13) Any violations of the primary drinking water standard that have occurred as a result of the presence of the contaminant in the drinking water and a brief and plainly worded statement of health concerns that resulted in the regulation of that contaminant. (C) The public water system's address and phone number to enable customers to obtain further information concerning contaminants and potential health effects. (4) Information on the levels of unregulated contaminants, if any, for which monitoring is required pursuant to state or federal law or regulation. (5) Disclosure of any variances or exemptions from primary drinking water standards granted to the system and the basis therefor. (b) On or before July 1, 1998, and every three years thereafter, public water systems serving more than 10,000 service connections that detect one or more contaminants in drinking water that exceed the applicable public health goal, shall prepare a brief written report in plain language that does all of the following: (1) Identifies each contaminant detected in drinking water that exceeds the applicable public health goal. (2) Discloses the munerieal public health risk, determined by the office, associated with the maximum contaminant level for each contaminant identified in paragraph (1) and the numerical public health risk determined by the office associated with the public health goal for that contaminant. 75C-15 (3) Identifies the category of risk to public health, including, but not limited to, carcinogenic, mutagenic, teratogenic, and acute toxicity, associated with exposure to the contaminant in drinking water, and includes a brief plainly worded description of these terms. (4) Describes the best available technology, if any is then available on a commercial basis, to remove the contaminant or reduce the concentration of the contaminant. The public water system may, solely at its own discretion, briefly describe actions that have been taken on its own, or by other entities, to prevent the introduction of the contaminant into drinking water supplies. (5) Estimates the aggregate cost and the cost per customer of utilizing the technology described in paragraph (4), if any, to reduce the concentration of that contaminant in drinking water to a level at or below the public health goal. (6) Briefly describes what action, if any, the local water purveyor intends to take to reduce the concentration of the contaminant in public drinking water supplies and the basis for that decision. (c) Public water systems required to prepare a report pursuant to subdivision (b) shall hold a public hearing for the purpose of accepting and responding to public comment on the report. Public water systems may hold the public hearing as part of any regularly scheduled meeting. (d) The department shall not require a public water system to take any action to reduce or eliminate any exceedance of a public health goal. (c) Enforcement of this section does not require the department to amend a public water system's operating permit. (f) Pending adoption of a public health goal by the Office of Environmental Health Hazard Assessment pursuant to subdivision (c) of Section 116365, and in lieu thereof, public water systems shall use the national maximum contaminant level goal adopted by the United States Environmental Protection Agency for the corresponding contaminant for purposes of complying with the notice and hearing requirements of this section. (g) This section is intended to provide an alternative form for the federally required consumer confidence report as authorized by 42 U.S.C. Section 300g-3(c). (Repealed and added by Stats. 1996, Ch. 755, Sec. 12. Effective January 1, 1997.) 75C-16 EXHIBIT 3 (Units are in milligrams per liter (mg/L), unless otherwise noted.) Last Update: March 13, 2019 This table includes: For comparison: California's maximum contaminant levels (MCLs) Detection limits for purposes of reporting (DLRs) Federal MCLs and Public health goals (PHGs) from the Office of Environmental Health Hazard Assessment Maximum Contaminant Level OEHHA Goals (MCLGs) (US Also, the PHG for NDMA (which is not yet regulated) is included at the bottom of this table. Ems_ Regulated Contaminant MCL I DLR PHG Date f MCL MCLG PHG Chemicals with MCLs in 22 CCR §64431—Inorganic Chemicals Aluminum I 1 I n n5 I n R 9nn1 = micron nbers per rater; for I 7 MFL 10.2 MFL I 7 MFL 1 2003 7 MFL 1 7 MFL Total - OEHHA withdrew the 0.05 0.01 I Novh. 2001 I 1999 I 0.1 0.1 L PHG Hexavalent - 0.01-mg/L MCL & __ __ 0.00002 2011 :rcury (inorganic) 0,002 0.001 1 0.0012 0.002 0.002 rev2005199g :kel 0.1 0.01 0.012 2001 :rate (as nitrogen, N) 10 as N 0.4 45 as NO3 2018 10 10 =10 as N :rite as N 1 as N 0.4 1 as N 2018 1 1 :rate + Nitrite as N 10 as N -- 10 as N 2018 rchlorate 0.006 0.004 0.001 2015 denium 0.05 0.005 0.03 2010 0.05 0.05 allium 0.002 0.001 0.0001 1999 0.002 0.0005 ev2004 Copper and Lead, 22 CCR §64672.3 Values referred to as MCLs for lead and copper are not actually MCLs; instead, they are called 'Action Levels" under the lead and copper rule U.U1b I U.UUb I U.000L I 2UU9 U.U1b I zero Radionuclides with MCLs in 22 CCR §64441 and §64443—Radioactivity [units are picocuries per liter (pCi/L), unless otherwise stated; n/a = not applicable] ; alpha particle activity- OEHHA ided in 2003 that a PHG was not 15 1 3 1 none n/a 15 zero in 2003 that a PHG was not I4 mrem/yr I 4 I none I n/a I 4 mrem/yr zero '.6 - 1 0.05 12006 R 1 1 n n14 9nnF Page 1 of 3 6/17/2019 75C-17 Regulated Contaminant MCL DLR PHG Date of PHG Radium-226 + Radium-228 5 Strontium-90 8 2 0.35 2006 Tritium 20,000 1 1,000 1 400 2006 Uranium 20 1 1 1 0.43 2001 Chemicals with MCLs in 22 CCR §64444-Organic Chemicals (a) Volatile Organic Chemicals (VOCs) Benzene 0.001 0.0005 0.00016 2001 Carbon tetrachloride 0.0005 0.0005 0.0001 2000 1,2-Dichlorobenzene 0.6 0.0005 0.6 1997 ev2009 1,4-Dichlorobenzene -DCB 0.005 0.0005 0.006 1997 1,1-Dichloroethane 1,1-DCA 0.005 0.0005 0.003 2003 1,2-Dichloroethane (1,2-DCA) 0.0005 0.0005 0.0004 1999 rev2005 1,1-Dichloroeth lene 1,1-DCE 0.006 0.0005 1 0.01 1999 cis-1,2-Dichloroeth lene 0.006 0.0005 0.013 2018 trans-1,2-Dichloroeth lene 0.01 0.0005 0.05 2018 Dichloromethane (Methylene chloride) 0.005 0.0005 0.004 2000 1,2-Dichloro ro ane 0.005 0.0005 0.0005 1999 1,3-Dichloropropene 0,0005 0.0005 0.0002 1999 rev2006 Eth (benzene 0.3 0.0005 0.3 1997 Methyl tertiary butyl ether MTBE 0.013 0.003 0.013 1999 Monochlorobenzene 0.07 0.0005 0.07 2014 Styrene 0.1 0.0005 0.0005 2010 1,1,2,2-Tetrachloroethane 0.001 0.0005 1 0.0001 2003 Tetrachloroeth lene PCE 0.005 0.0005 1 0.00006 2001 Toluene 0.15 0.0005 0.15 1999 1,2,4-Trichoorobenzene 0.005 0.0005 0.005 1999 1,1,1-Trichloroethane 1,1,1-TCA 0.200 0.0005 1 2006 1,1,2-Trichloroethane 1,1,2-TCA 0.005 0.0005 0.0003 2006 Trichloroeth lene TCE 0.005 0.0005 0.0017 2009 Trichlorofluoromethane Freon 11 0.15 0.005 1.3 1 2014 1,1,2-Trichloro-1,2,2-Trifluoroethane (Freon 113 1.2 0.01 4 1997 rev2011 Vinyl chloride 0.0005 0.0005 0.00005 2000 X lenes 1.750 0.0005 1 1.8 1997 (b) Non -Volatile Synthetic Organic Chemicals (SOCs) Alachlor 0.002 0.001 0.004 1997 Atrazine 0.001 0.0005 0.00015 1999 Bentazon 0.018 0.002 0.2 1999 ev2009 Benzo a rene 0.0002 0.0001 0.000007 2010 Carbofuran 0.018 0.005 0.0007 2016 Chlordane 0.0001 0.0001 0.00003 1997 rev2006 Dalapon 0.2 0.01 0.79 1997 rev2009 1,2-Dibromo-3-chloropropane(DBCP) 0.0002 0.00001 1 0.0000017 1999 2,4-Dichlorophenoxyacetic acid (2,4-D) 0.07 0.01 0.02 2009 Di 2-eth (hex I adi ate 0.4 0.005 0.2 2003 Di 2-eth (hex I hthalate DEHP 0.004 0.003 1 012 1997 Dinoseb 0.007 0.002 0.014 1997 rev2010 Page 2 of 3 MCL MCLG 5 zero 30 µ /L zero 0.005 zero 0.005 zero 0.6 0.6 0.075 0.075 0.005 zero 0.007 0.007 0.07 0.07 0.1 0.1 0.005 zero 0.005 zero 0.7 0.7 01 0.1 0.1 0.1 0.1 0.1 0.005 zero 1 1 0.07 0.07 0.2 0.2 0.005 0.003 0.005 zero 0.002 zero 10 10 0.002 zero 0.003 0.003 0.0002 zero 0.04 0.04 0.002 zero 0.2 0.2 0.0002 zero 0.07 0.07 0.4 0.4 0.006 zero 0.007 0.007 6/17/2019 75C-18 Regulated Contaminant I MCL I DLR I PHG I Date of I I MCL MCLG u.uui I u.000b u.uuuu3 1 2uu3 1 1 u.uu1 I zero 0.05 1 0.05 1 0.05 0.0002 1 0.0002 0.000032 1999 0.0002 0.0002 Toxa heney 0.003 0.001 0.0000312018draft 0.003 zero 1,2,3-Trichloropropane 0.000005 0.000005 0.0000007 2,3,7,8-TCDD (dioxin) 3x10'e 5x10-9 5x10-1' 3x10"e zero 2,4,5-TP Silvex 0.05 0.001 0.003 0.05 0.05 Chemicals with MCLs in 22 CCR §64533-Disinfection Byproducts Total Trihalomethanes 0.080 - 0.080 Bromodichloromethane -- 0.0010 0.00006 zero Bromoform 0.0010 0.0005 zero Chloroform 0.0010 0.0004 2018 draft - 0.07 Dibromochloromethane - 0.0010 0.0001 2018 draft 0.06 Haloacetic Acids (five) (HAA5) 0.060 -- 0.060 MonochloroaceticAcid - 0.0020 - 0.07 Dichloroacetic Adic 0.0010 -- zero Trichloroacetic Acid 0.0010 -- 0.02 Monobromoacetic Acid 0.0010 -- Dibromoacetic Acid -- 0.0010 - Bromate 0.010 0.0050** 0.0001 2009 0.01 zero Chlorite 1.0 0.020 0.05 2009 1 0.8 Chemicals with PHGs established in response to DDW requests. These are not currently regulated drinking water contaminants. N-Nitrosodimethylamine (NDMA) I - I -- 1 0.000003-- *OEHHA's review of this chemical during the year indicated (rev20XX) resulted in no change in the PHG. **The DLR for Bromate is 0.0010 mg/L for analysis performed using EPA Method 317.0 Revision 2.0, 321.8, or 326.0. Page 3 of 3 6/17/2019 75C-19 75C-20