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Pomona - City, Water Dept. - Los Angeles, CA

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Serves 156,500 people - Test data available: 2004-2009

This drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group (EWG) by the California Department of Public Health. It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results. Water utilities nationwide detected more than 300 pollutants between 2004 and 2009. More than half of these chemicals are unregulated, legal in any amount. Despite this widespread contamination, the federal government invests few resources to protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes test results for this utility and lists potential health concerns.

	This Drinking Water System	National Average
Exceed Health GuidelinesTests showing chemicals at concentrations above health guidelines established by federal and state health agencies. These guidelines are typically set at a levels that pose no significant health risk.	24 chemicals	4
Health Standard ExceedencesChemicals detected at concentrations above the legal limit, the Maximum Contaminant Level (MCLs) established by the U.S. EPA. Most MCLs are based on annual averages, so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.	10 chemicals	0.5
Pollutants FoundThe total number of contaminants detected since 2004, according to data provided by the state water agency.	48 chemicals	8
Tests ConductedThe total number of number of water quality tests conducted by water utilities and recorded in data provided by the state water agency.	34,009 tests	420

Contaminants Exceeding Health Guidelines

Contaminant	Average/ Maximum Result	Health Limit Exceeded	Legal Limit Exceeded	Testing History -Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
NitrateNitrate enters drinking water sources from fertilizer runoff, leaching septic tanks, and erosion of natural deposits; it is also emitted by chemical, petrochemical and metal-finishing industries.	7.17 ppm 19.43 ppm	Yes 10 ppm	Yes 10 ppm
TrichloroethyleneTrichloroethylene is used to remove grease from fabricated metal parts and in the production of some textiles; this pollutant comes from metal degreasing sites, metal finishing and rubber processing industries.	1.87 ppb 11.67 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	Yes 5 ppb
TetrachloroethyleneTetrachloroethylene (perc) is a common soil and groundwater contaminant used in dry cleaning and as a solvent in automotive and metalworking factories and other industries.	1.36 ppb 14 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	Yes 5 ppb
1,1-DichloroethyleneIndustrial chemical pollutant from manufacture of adhesives, synthetic fibers, refrigerants and plastic wraps.	1.42 ppb 21 ppb	Yes 7 ppb	Yes 7 ppb
Nitrate & nitriteNitrate and nitrite enter water from fertilizer runoff, leaching from septic tanks, and erosion of natural deposits.	7.73 ppm 19 ppm	Yes 10 ppm	Yes 10 ppm
AluminumAluminum is a metal released from metal refineries and mining operations.	94.36 ppb 1000 ppb	Yes 200 ppb	Yes 200 ppb
Arsenic (total)Arsenic contaminates drinking water due to mining runoff, erosion of natural deposits, emissions from glass and electronics processing and the use of arsenical compounds as wood preservatives and pesticides.	2.58 ppb 15 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	Yes 10 ppb
Chromium (total)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.	9.86 ppb 170 ppb	Yes 100 ppb	Yes 100 ppb
Chromium (hexavalent)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.	12.44 ppb 170 ppb	Yes	Yes 100 ppb
ManganeseManganese is a naturally occurring element released from mineral deposits as well as industrial use.	2.35 ppb 93 ppb	Yes 50 ppb	Yes 50 ppb
PerchloratePerchlorate is a synthetic oxygen additive in solid fuel propellant for rockets, missiles, and fireworks, and is primarily used by the military and the space industry; it may occur naturally in certain imported agricultural fertilizers.	5.4 ppb 17 ppb	Yes 5 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
n-Nitrosodimethylaminen-Nitrosodimethylamine is a carcinogenic water contaminant released from various industrial processes; it also forms in drinking water as disinfection byproduct of chloramination and from agricultural runoff.	0.02 ppb 0.26 ppb	Yes <0.01 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Alpha particle activityAlpha particles are a form of radiation released from mining waste pollutants and natural sources.	2.42 pCi/L 10.5 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	No 15 pCi/L
Lead (total)Lead is a metal that enters water by corrosion of household plumbing systems, discharge of industrial pollution and erosion of natural deposits.	0.46 ppb 4.3 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No
BromoformBromoform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.33 ppb 2.95 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 80 ppb
Radium-226Radium-226 is a radioactive element usually found around uranium deposits.	0.07 pCi/L 0.47 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	No 5 pCi/L
BromodichloromethaneBromodichloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.64 ppb 7.2 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 80 ppb
Radium-228Radium-228 is a radioactive element usually found around uranium deposits.	0.08 pCi/L 0.88 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	No 5 pCi/L
DibromochloromethaneDibromochloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.66 ppb 7 ppb	Yes 0.4 ppb	No 80 ppb
Total trihalomethanes (TTHMs)Total trihalomethanes constitute the sum of four disinfection byproducts: chloroform, bromodichloromethane, dibromochloromethane, and bromoform.	2.55 ppb 22 ppb	Yes 9.8 ppb	No 80 ppb
ChloroformChloroform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.93 ppb 10 ppb	Yes 5.7 ppb	No 80 ppb
1,2-Dibromo-3-chloropropane (DBCP)1,2-Dibromo-3-chloropropane is a persistent pesticide and groundwater contaminant associated with male sterility and severe reproductive toxicity; historically used as a soil fumigant on bananas and pineapples; banned by EPA in early 1980s.	<0.01 ppb <0.01 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 0.2 ppb
Total haloacetic acids (HAAs)Total haloacetic acids refers to the sum of the concentrations of five related disinfection byproducts in a water sample: dichloroacetic acid, trichloroacetic acid, monochloroacetic acid, monobromoacetic acid and dibromoacetic acid.	7.2 ppb 7.2 ppb	Yes 0.7 ppb	No 60 ppb
Dichloroacetic acidDichloroacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	2.4 ppb 2.4 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 60 ppb
NOTE: Each dot in the above graph represents one month. * Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Other Detected Contaminants

Contaminant	Average/ Maximum Result	Health Limit Exceeded	Legal Limit Exceeded	Testing History -Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Barium (total)Barium is a mineral that enters drinking water through drilling and mining waste runoff, discharges from chemical industries and erosion of natural deposits.	53.42 ppb 110 ppb	No 700 ppb	No 2000 ppb
CopperCopper is a naturally occuring metal and drinking water contaminant that enters tap water by corrosion of household plumbing systems and erosion of natural deposits.	3.48 ppb 29 ppb	No 300 ppb	No 1000 ppb
Selenium (total)Selenium is a naturally occurring element that contaminates water due to mining or petrolum refining, fly-ash from coal-burning power plants, and irrigation of arid farmland soils high in selenium.	1.02 ppb 11 ppb	No 50 ppb	No 50 ppb
Combined Uranium (pCi/L)Uranium is a radioactive element commonly found in most rocks; processed ore is used for power generation and weapons manufacture.	1.81 pCi/L 7.3 pCi/L	No	No 15 pCi/L
Gross beta particle activity (pCi/L)Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits.	1.59 pCi/L 4.85 pCi/L	No	No 15 pCi/L
TritiumTritium is a pollutant from commercial nuclear reactors, research reactors and government weapons production plants.	160.9 pCi/L 627.67 pCi/L	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Strontium-90Strontium-90 is a radioactive pollutant from nuclear fallout and possibly weapons and power production.	0.16 pCi/L 1.2 pCi/L	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
DichlorodifluoromethaneDichlorodifluoromethane (Freon 12) is a chlorofluorocarbon refrigerant and aerosol spray propellant; it was banned under the Montreal Protocol as of 2000 because of its ozone-depleting properties.	0.09 ppb 2.25 ppb	No 1000 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
MTBEMTBE (methyl tert-butyl ether) is a fuel additive that had been used as an octane enhancer in unleaded gasoline; it contaminates groundwater due to spillage or leakage at gas stations, and has been banned or scheduled for phaseout in most states.	0.44 ppb 12 ppb	No 13 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
ChloromethaneChloromethane is a naturally occuring chemical that forms during combustion of plant material; it may be released from the manufacture of silicone, rubber and pesticides, and also forms as a byproduct of water disinfection.	0.03 ppb 2.19 ppb	No 30 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
VanadiumVanadium is a metal used as an alloying addition to iron & steel; it is discharged from ceramic, glass, textile, photography, metallurgy and rubber industries.	4.28 ppb 6.6 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
o-Dichlorobenzeneo-Dichlorobenzene (1,2-Dichlorobenzene) is an intermediate for making herbicides; it is discharged as a pollutant from the manufacture of agricultural chemicals.	0.15 ppb 8.68 ppb	No 420 ppb	No 600 ppb
trans-1,2-Dichloroethylenetrans-1,2-Dichloroethylene is a synthetic chemical used as a solvent, refrigerant, and in the production of pharmaceuticals; it is released as pollutant from various industrial chemical factories.	<0.01 ppb 0.48 ppb	No 100 ppb	No 100 ppb
1,1-Dichloroethane1,1-Dichloroethane is used in industrial chemical synthesis, as a solvent for plastics, paint, varnish, and finish removers and as an insecticide/fumigant.	0.01 ppb 1.61 ppb	No 3 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
TolueneToluene is a pollutant from petroleum refineries and a chemical used in plastics manufacturing as well as the pharmaceutical, paint and furniture industries.	<0.01 ppb 0.12 ppb	No 150 ppb	No 1000 ppb
BromochloromethaneBromochloromethane is a tap water disinfection byproduct; it is also used as an intermediate in chemical manufacturing and a fire extinguishing agent.	<0.01 ppb 0.43 ppb	No 50 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Silver (total)Silver is an element from natural deposits and mining wastes; it is also associated with the development of photographic and x-ray film and the use of silver in antibacterial consumer products.	<0.01 ppb 0.24 ppb	No 100 ppb	No 100 ppb
Antimony (total)Antimony is a metal that enters water from petroleum refinery pollution, fire retardants, ceramics, electronics and solder.	0.01 ppb 0.84 ppb	No 5.6 ppb	No 6 ppb
DacthalDacthal (DCPA) is an herbicide used on golf courses, home lawns and gardens, and strawberries, cotton, and soybeans; dacthal and its degradates are among the most commonly detected pesticide residues in drinking water wells.	0.01 ppb 0.14 ppb	No 70 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
N-nitrosodi-n-butylamine (ndba)N-nitrosodi-n-butylamine is a synthetic chemical used in research and as an intermediate for production of other chemicals.	0.73 ppb 2.2 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Bromodichloroacetic acidBromodichloroacetic acid is a disinfection byproduct that forms when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	2.9 ppb 2.9 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Dibromoacetic acidDibromoacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	2.7 ppb 2.7 ppb	No	No 60 ppb
Trichloroacetic acidTrichloroacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	2.1 ppb 2.1 ppb	No 20 ppb	No 60 ppb
ChlorateChlorate is a disinfection byproduct (unregulated chlorine dioxide byproduct), an herbicide and a pollutant from explosives.	63.33 ppb 63.33 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
NOTE: Each dot in the above graph represents one month. * Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Contaminants Not Detected - 148 chemicals

1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloropropene, 1,2,3-Trichlorobenzene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2,4-Trimethylbenzene, 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichloropropane, 1,3-Dichloropropene, 2,2-Dichloropropane, 2,3,7,8-TCDD (Dioxin), 2,4,5-TP (Silvex), 2,4-d, 2,4-db, 2-Chloroethylvinyl ether, 3-Hydroxycarbofuran, 4,4-dde, Acetone, Acifluorfen (Blazer), Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, alpha-Lindane, Aroclor 1221, Aroclor 1232, Aroclor 1242, Aroclor 1248, Aroclor 1254, Aroclor 1260, Asbestos, Atrazine, Baygon (Propoxur), Bentazon (Basagran), Benzene, Benzo[a]pyrene, Beryllium (total), beta-Lindane, Bromacil, Bromobenzene, Bromomethane, Butachlor, Cadmium (total), Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chloroethane, Chlorothalonil (Bravo), Chlorpropham, cis-1,2-Dichloroethylene, cis-1,3-Dichloropropene, Cyanide, Dalapon, delta-BHC, Di(2-Ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Di-n-octylphthalate, Diazinon (Spectracide), Dibenz[a,h]anthracene, Dibromomethane, Dicamba, Dichloromethane (methylene chloride), Dichlorprop, Dieldrin, Dimethoate, Dinoseb, Diphenamide, Diquat, Diuron, Endosulfan I, Endosulfan II, Endosulfan Sulfate, Endothall, Endrin, Endrin Aldehyde, Ethyl-t-butyl ether (ETBE), Ethylbenzene, Ethylene dibromide (EDB), Glyphosate, Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Isopropyl ether, Isopropylbenzene, Lindane, m- & p- Xylene, m-Dichlorobenzene, m-Xylene, Mercury (total inorganic), Methiocarb, Methomyl, Methoxychlor, Methyl ethyl ketone, Methyl isobutyl ketone, Metolachlor, Metribuzin, Molinate (Ordram), Monobromoacetic acid, Monochloroacetic acid, Monochlorobenzene (Chlorobenzene), n-Butylbenzene, n-Nitroso di-N-Propylamine, n-Nitrosodiphenylamine, N-nitrosopiperidine (npip), N-nitrosopyrrolidine (npyr), n-Propylbenzene, Naphthalene, Nitrite, Nitrobenzene, o-Chlorotoluene, o-Xylene, Oxamyl (Vydate), p,p'-DDT, p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, p-Xylene, Pentachlorophenol, Picloram, Prometon, Prometryn, Propachlor, sec-Butylbenzene, Simazine, Styrene, Terbacil, Tert-Amyl-Methyl Ether, Tert-Butyl Alcohol, tert-Butylbenzene, Thallium (total), Thiobencarb (Bolero), Total polychlorinated biphenyls (PCBs), Toxaphene, trans-1,3-Dichloropropene, Trichlorofluoromethane, Trichlorotrifluoroethane, Trifluralin, Vinyl chloride, Xylenes (total)

Pollution Summary

48	Total Contaminants Detected (2004 - 2009) Chlorate, Barium (total), Copper, Selenium (total), Silver (total), Antimony (total), Vanadium, Dacthal, Chloromethane, Dichlorodifluoromethane, MTBE, Bromochloromethane, Trichloroacetic acid, Dibromoacetic acid, o-Dichlorobenzene, 1,1-Dichloroethane, trans-1,2-Dichloroethylene, Toluene, Tritium, Strontium-90, Bromodichloroacetic acid, N-nitrosodi-n-butylamine (ndba), Combined Uranium (pCi/L), Gross beta particle activity (pCi/L), Aluminum, Arsenic (total), Chromium (total), Lead (total), Manganese, Nitrate & nitrite, Nitrate, Chromium (hexavalent), n-Nitrosodimethylamine, Dichloroacetic acid, Total haloacetic acids (HAAs), 1,2-Dibromo-3-chloropropane (DBCP), Chloroform, Bromoform, Bromodichloromethane, Dibromochloromethane, Total trihalomethanes (TTHMs), 1,1-Dichloroethylene, Trichloroethylene, Tetrachloroethylene, Radium-226, Radium-228, Alpha particle activity, Perchlorate
10	Agricultural Pollutants (pesticides, fertilizer, factory farms) Chlorate, Selenium (total), Dacthal, o-Dichlorobenzene, Arsenic (total), Nitrate & nitrite, Nitrate, n-Nitrosodimethylamine, 1,2-Dibromo-3-chloropropane (DBCP), Perchlorate
10	Sprawl and Urban Pollutants (road runoff, lawn pesticides, human waste) Nitrate, Copper, Nitrate & nitrite, Lead (total), Arsenic (total), Tetrachloroethylene, MTBE, Antimony (total), Silver (total), Dacthal
34	Industrial Pollutants Chlorate, Barium (total), Selenium (total), Silver (total), Antimony (total), Vanadium, Chloromethane, Dichlorodifluoromethane, MTBE, Bromochloromethane, 1,1-Dichloroethane, trans-1,2-Dichloroethylene, Toluene, Tritium, Strontium-90, N-nitrosodi-n-butylamine (ndba), Combined Uranium (pCi/L), Gross beta particle activity (pCi/L), Aluminum, Arsenic (total), Chromium (total), Lead (total), Manganese, Nitrate & nitrite, Nitrate, Chromium (hexavalent), n-Nitrosodimethylamine, 1,1-Dichloroethylene, Trichloroethylene, Tetrachloroethylene, Radium-226, Radium-228, Alpha particle activity, Perchlorate
14	Water Treatment and Distribution Byproducts (pipes and fixtures, treatment chemicals and byproducts) Total trihalomethanes (TTHMs), Total haloacetic acids (HAAs), Chloroform, Bromodichloromethane, Dibromochloromethane, Dichloroacetic acid, Trichloroacetic acid, Bromoform, Dibromoacetic acid, Bromodichloroacetic acid, Chloromethane, n-Nitrosodimethylamine, Chlorate, Bromochloromethane
18	Naturally Occurring (naturally present but increased for lands denuded by sprawl, agriculture, or industrial development) Nitrate, Copper, Nitrate & nitrite, Barium (total), Lead (total), Arsenic (total), Manganese, Radium-228, Radium-226, Alpha particle activity, Gross beta particle activity (pCi/L), Combined Uranium (pCi/L), Chromium (total), Aluminum, Selenium (total), Chromium (hexavalent), Chloromethane, Silver (total)
15	Unregulated Contaminants EPA has not established a maximum legal limit in tapwater for these contaminants Chlorate, Vanadium, Dacthal, Chloromethane, Dichlorodifluoromethane, MTBE, Bromochloromethane, 1,1-Dichloroethane, Tritium, Strontium-90, Bromodichloroacetic acid, N-nitrosodi-n-butylamine (ndba), Lead (total), n-Nitrosodimethylamine, Perchlorate

EPA Violation Summary

No violations were reported for this system since 2004.

Information on violations is drawn directly from EPA's national violations database in the Agency's Safe Drinking Water Information System. Analyses by others have raised questions about the quality of the information in EPA's database. For the purposes of this investigation, EWG is not showing below or including in our analyses, those violations for individual water suppliers that occurred on days for which the total number of violations assigned by EPA to that water supplier was greater than 20. This criteria was based on common characteristics of incorrect violations data as identified by water utilities, from a review of EPA's violations data by several hundred utilities prior to the release of EWG's investigation.