The Power of Information

National Drinking Water Database


Atwater Utilities - Atwater, MN


Serves 1,079 people

Radon

Radon is a radioactive breakdown product of radium and uranium in soil, rock and water; it is often present in groundwater.
 
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
4 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
4 days
Tests ConductedNumber of individual tests done for this contaminant
8 tests

Testing Summary

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
RadonRadon is a radioactive breakdown product of radium and uranium in soil, rock and water; it is often present in groundwater.275 pCi/L
327 pCi/L
Yes
1.5 pCi/L
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.

Health Based and Legal Limits for Radon

Health Based Limits for Radon

StandardDescriptionLevel
One in one million (10-6) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 1,000,000. Source: U.S. Environmental Protection Agency.1.5 pCi/L
One in ten thousand (10-4) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 10,000. Source: U.S. Environmental Protection Agency.150 pCi/L

Testing Results

Testing DateAverage
Result
Samples taken that dayNumber of Non-DetectsRange of Results
2005-11-28327 pCi/L20261 to 393 pCi/L
2005-07-11232.5 pCi/L20213 to 252 pCi/L
2005-04-19305 pCi/L20199 to 411 pCi/L
2005-02-09235.5 pCi/L20233 to 238 pCi/L