The Power of Information

National Drinking Water Database


Chapel Hill - Bel Air, MD


Serves 13,152 people - Test data available: 2004-2007

This drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group (EWG) by the Maryland Department of Environment. 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.
10 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.
0 chemicals
0.5
Pollutants FoundThe total number of contaminants detected since 2004, according to data provided by the state water agency.
22 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.
1,652 tests
420

Contaminants Exceeding Health Guidelines

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Total trihalomethanes (TTHMs)Total trihalomethanes constitute the sum of four disinfection byproducts: chloroform, bromodichloromethane, dibromochloromethane, and bromoform.38.31 ppb
61.03 ppb
Yes
9.8 ppb
No
80 ppb
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.8.41 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
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.27.79 ppb
48 ppb
Yes
5.7 ppb
No
80 ppb
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.1.87 ppb
3.68 ppb
Yes
0.4 ppb
No
80 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.17.39 ppb
36.75 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.6.5 ppb
12.25 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
Di(2-ethylhexyl) phthalateDi(2-ethylhexyl) phthalate is a pollutant from rubber and industrial chemical factories and a leachate from PVC pipes; it is classified by EPA as a probable human carcinogen.0.37 ppb
1.6 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
6 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.8.63 ppb
24.5 ppb
Yes
20 ppb
No
60 ppb
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.0.01 ppb
0.25 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
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.1 ppb
5 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
10 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

ContaminantAverage/
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.3.5 ppm
4.4 ppm
No
10 ppm
No
10 ppm
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.0.27 ppb
1.83 ppb
NoNo
60 ppb
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.18.75 ppb
22 ppb
No
700 ppb
No
2000 ppb
Monochloroacetic acidMonochloroacetic 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.1.57 ppb
17.3 ppb
No
70 ppb
No
60 ppb
Monobromoacetic acidMonobromoacetic 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.0.42 ppb
5.75 ppb
NoNo
60 ppb
MetolachlorMetolachlor is an herbicide applied on corn, soybeans, peanuts, cotton and pod crops.0.28 ppb
1.7 ppb
No
700 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
2,4-D2,4-D is a chlorophenol herbicide used on row crops, lawns and golf courses.0.07 ppb
0.37 ppb
No
20 ppb
No
70 ppb
Gross beta particle activity (pCi/L)Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits.0.6 pCi/L
3 pCi/L
NoNo
15 pCi/L
DicambaDicamba is an herbicide applied in agriculture, rangeland, pasture and industry; it is used for corn, wheat and other crops.0.03 ppb
0.13 ppb
No
3000 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
PicloramPicloram is an herbicide that may contaminate drinking water sources due to runoff from applications to pasture, rangeland and rights-of-way.0.03 ppb
0.11 ppb
No
500 ppb
No
500 ppb
DalaponDalapon is an herbicide used on roads, railway tracks and other rights of way.0.06 ppb
0.22 ppb
No
200 ppb
No
200 ppb
CyanideCyanide is a chemical used in mining and steel/metal, plastic, and pesticide manufacturing; it is applied to roads as road salts, and small quantities occur naturally in some plants.3 ppb
6 ppb
No
80 ppb
No
200 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.

Contaminants Not Detected - 98 chemicals

1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloroethane, 1,1-Dichloroethylene, 1,1-Dichloropropene, 1,2 Dibromo-3-chloropropane (DBCP), 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, 2,4,5-t, 2,4,5-TP (Silvex), 3-Hydroxycarbofuran, Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Alpha particle activity (excl radon and uranium), Antimony (total), Atrazine, Benzene, Benzo[a]pyrene, Beryllium (total), Bromobenzene, Bromochloromethane, Bromomethane, Butachlor, Cadmium (total), Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chloroethane, Chloromethane, Chromium (total), cis-1,2-Dichloroethylene, Combined Radium (-226 & -228), Di(2-Ethylhexyl) adipate, Dibromomethane, Dichlorodifluoromethane, Dichloromethane (methylene chloride), Dieldrin, Dinoseb, Endrin, Ethylbenzene, Ethylene dibromide (EDB), Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Isopropylbenzene, Lindane, m-Dichlorobenzene, m-Xylene, Mercury (total inorganic), Methomyl, Methoxychlor, Metribuzin, Monochlorobenzene (Chlorobenzene), Mtbe, n-Butylbenzene, n-Propylbenzene, Naphthalene, o-Chlorotoluene, o-Dichlorobenzene, o-Xylene, Oxamyl (Vydate), p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, p-Xylene, Pentachlorophenol, Propachlor, Radium-228, sec-Butylbenzene, Selenium (total), Simazine, Styrene, tert-Butylbenzene, Tetrachloroethylene, Thallium (total), Toluene, Toxaphene, trans-1,2-Dichloroethylene, Trichloroethylene, Trichlorofluoromethane, Vinyl chloride, Xylenes (total)

Pollution Summary

22Total Contaminants Detected (2004 - 2007)

Barium (total), Cyanide, Nitrate, Dalapon, Picloram, Metolachlor, 2,4-D, Dicamba, Monochloroacetic acid, Monobromoacetic acid, Dibromoacetic acid, Gross beta particle activity (pCi/L), Arsenic (total), Di(2-ethylhexyl) phthalate, Dichloroacetic acid, Trichloroacetic acid, Total haloacetic acids (HAAs), Chloroform, Bromoform, Bromodichloromethane, Dibromochloromethane, Total trihalomethanes (TTHMs)

8Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Cyanide, Nitrate, Dalapon, Picloram, Metolachlor, 2,4-D, Dicamba, Arsenic (total)

5Sprawl and Urban Pollutants
(road runoff, lawn pesticides, human waste)

Cyanide, Nitrate, Dalapon, 2,4-D, Arsenic (total)

6Industrial Pollutants

Barium (total), Cyanide, Nitrate, Gross beta particle activity (pCi/L), Arsenic (total), Di(2-ethylhexyl) phthalate

12Water 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, Monochloroacetic acid, Monobromoacetic acid, Di(2-ethylhexyl) phthalate

5Naturally Occurring
(naturally present but increased for lands denuded by sprawl, agriculture, or industrial development)

Nitrate, Barium (total), Arsenic (total), Gross beta particle activity (pCi/L), Cyanide

2Unregulated Contaminants
EPA has not established a maximum legal limit in tapwater for these contaminants

Metolachlor, Dicamba

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.