The Power of Information

National Drinking Water Database


Redlands City Mud-Water Div Utilities - San Bernardino, CA


Serves 69,300 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
69 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
72 days
Tests ConductedNumber of individual tests done for this contaminant
131 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.596.5 pCi/L
2300 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
2007-03-20792 pCi/L10792 pCi/L
2007-02-14793 pCi/L10793 pCi/L
2007-02-07447 pCi/L10447 pCi/L
2007-02-06341 pCi/L10341 pCi/L
2007-01-22682 pCi/L10682 pCi/L
2006-11-21540.5 pCi/L20430 to 651 pCi/L
2006-11-09342.5 pCi/L20321 to 364 pCi/L
2006-11-07534 pCi/L10534 pCi/L
2006-11-01942.5 pCi/L20535 to 1350 pCi/L
2006-10-3160.5 pCi/L210 to 121 pCi/L
2006-10-30583 pCi/L20541 to 625 pCi/L
2006-10-24971 pCi/L210 to 1942 pCi/L
2006-10-18284.5 pCi/L20204 to 365 pCi/L
2006-10-160 pCi/L110 pCi/L
2006-10-12721 pCi/L20574 to 868 pCi/L
2006-10-11557.5 pCi/L20224 to 891 pCi/L
2006-10-10370.5 pCi/L20146 to 595 pCi/L
2006-10-051190 pCi/L101190 pCi/L
2006-10-04372 pCi/L20164 to 580 pCi/L
2006-09-18273.5 pCi/L20221 to 326 pCi/L
2006-09-131037 pCi/L20344 to 1730 pCi/L
2006-09-12350.5 pCi/L20347 to 354 pCi/L
2006-08-31358.33 pCi/L30127 to 500 pCi/L
2006-08-29390 pCi/L40101 to 692 pCi/L
2006-08-28480.5 pCi/L20408 to 553 pCi/L
2006-08-23106 pCi/L10106 pCi/L
2006-08-22639 pCi/L20579 to 699 pCi/L
2006-08-210 pCi/L220 pCi/L
2006-08-16537 pCi/L20525 to 549 pCi/L
2006-08-15756.75 pCi/L40127 to 1430 pCi/L
2006-06-29846 pCi/L10846 pCi/L
2006-06-28628 pCi/L10628 pCi/L
2006-06-27358 pCi/L10358 pCi/L
2006-06-21681 pCi/L10681 pCi/L
2006-06-08264 pCi/L307 to 448 pCi/L
2006-06-055 pCi/L105 pCi/L
2006-06-01466.5 pCi/L20433 to 500 pCi/L
2006-05-15855 pCi/L20833 to 877 pCi/L
2006-05-091499 pCi/L20774 to 2224 pCi/L
2006-04-20705 pCi/L20699 to 711 pCi/L
2006-04-18586.25 pCi/L40204 to 1392 pCi/L
2006-04-05796 pCi/L10796 pCi/L
2006-03-291029 pCi/L30226 to 1465 pCi/L
2006-03-28425.5 pCi/L40348 to 562 pCi/L
2006-03-27971.33 pCi/L30802 to 1201 pCi/L
2006-03-23135 pCi/L20116 to 154 pCi/L
2006-03-22827.25 pCi/L40715 to 874 pCi/L
2006-03-16909 pCi/L20267 to 1551 pCi/L
2006-03-15501.33 pCi/L308 to 750 pCi/L
2006-03-1411.5 pCi/L205 to 18 pCi/L
2005-02-02615 pCi/L20600 to 630 pCi/L
2004-04-120 pCi/L110 pCi/L
2004-03-31190 pCi/L10190 pCi/L
2004-03-29330 pCi/L10330 pCi/L
2004-03-25730 pCi/L10730 pCi/L
2004-03-24675 pCi/L20610 to 740 pCi/L
2004-03-15430 pCi/L10430 pCi/L
2004-03-01680 pCi/L10680 pCi/L
2004-02-252300 pCi/L102300 pCi/L
2004-02-24830 pCi/L10830 pCi/L
2004-02-19600 pCi/L10600 pCi/L
2004-02-18210 pCi/L20180 to 240 pCi/L
2004-02-12545 pCi/L20530 to 560 pCi/L
2004-02-11650 pCi/L20640 to 660 pCi/L
2004-02-05130 pCi/L10130 pCi/L
2004-02-041400 pCi/L101400 pCi/L
2004-01-28960 pCi/L10960 pCi/L
2004-01-27495 pCi/L20190 to 800 pCi/L
2004-01-14500 pCi/L210 to 1000 pCi/L
2004-01-13610 pCi/L10610 pCi/L
2004-01-121315 pCi/L20730 to 1900 pCi/L
2004-01-08800 pCi/L20700 to 900 pCi/L