The Power of Information

National Drinking Water Database

Washington Suburban Sanitary Commission Utilities - Silver Spring, MD

Serves 1,800,000 people

Gross beta particle activity (pCi/L)

Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits.
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
0 days
Test Days Exceeding Legal LimitsNumber of days in which the samples taken in that day exceed the Maximum Contaminant Level (Depending on the contaminant and its MCL, that may or may not trigger an MCL violation. Some MCLs are based on averages spanning several months to a year)
0 days
Test DaysNumber of days in which this chemical has reported results in the data we received from the State
36 days
Tests ConductedNumber of individual tests done for this contaminant
98 tests

Testing Summary

Health Limit
Legal Limit

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Gross beta particle activity (pCi/L)Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits.2.86 pCi/L
7 pCi/L
15 pCi/L
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.

Health Based and Legal Limits for Gross beta particle activity (pCi/L)

Health Based Limits for Gross beta particle activity (pCi/L)

Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.15 pCi/L

Testing Results

Testing DateAverage
Samples taken that dayNumber of Non-DetectsRange of Results
2007-12-314.25 pCi/L403 to 5 pCi/L
2007-11-306.5 pCi/L206 to 7 pCi/L
2007-10-315 pCi/L204 to 6 pCi/L
2007-09-303.5 pCi/L203 to 4 pCi/L
2007-08-313.5 pCi/L203 to 4 pCi/L
2007-06-304 pCi/L104 pCi/L
2007-05-312 pCi/L210 to 4 pCi/L
2007-04-301.6 pCi/L530 to 5 pCi/L
2007-03-313.25 pCi/L403 to 4 pCi/L
2007-02-283 pCi/L203 pCi/L
2007-01-317 pCi/L107 pCi/L
2006-12-313.67 pCi/L310 to 7 pCi/L
2006-11-302 pCi/L210 to 4 pCi/L
2006-10-312 pCi/L210 to 4 pCi/L
2006-09-302 pCi/L420 to 4 pCi/L
2006-08-310 pCi/L220 pCi/L
2006-07-314 pCi/L104 pCi/L
2006-06-301.75 pCi/L420 to 4 pCi/L
2006-04-111.5 pCi/L210 to 3 pCi/L
2005-12-012.33 pCi/L310 to 4 pCi/L
2005-10-313 pCi/L103 pCi/L
2005-07-073 pCi/L203 pCi/L
2005-05-111.5 pCi/L210 to 3 pCi/L
2005-04-020 pCi/L220 pCi/L
2005-03-302.75 pCi/L420 to 7 pCi/L
2004-12-311 pCi/L430 to 4 pCi/L
2004-11-305.5 pCi/L605 to 6 pCi/L
2004-09-302 pCi/L520 to 4 pCi/L
2004-08-315 pCi/L204 to 6 pCi/L
2004-07-314.5 pCi/L204 to 5 pCi/L
2004-06-301.75 pCi/L420 to 4 pCi/L
2004-05-312.5 pCi/L210 to 5 pCi/L
2004-04-304 pCi/L304 pCi/L
2004-03-311.75 pCi/L420 to 4 pCi/L
2004-02-290 pCi/L220 pCi/L
2004-01-312 pCi/L310 to 3 pCi/L