Laserfiche WebLink
State Water Resources Control Board <br /> Division of Water Quality <br /> GAMA Program <br /> REGULATORY AND WATER QUALITY LEVELS <br /> Type Agency Concentration <br /> Federal US EPA No coliforms in drinking water <br /> MCLG' <br /> Federal US EPA Public water systems must not find total coliforms in <br /> MCL over 5.0% of all samples taken in a month, where the <br /> number of samples collected per month is based on the <br /> population served. If a sample tests positive for total <br /> coliforms a set of repeat samples must be collected <br /> within 24 hours. If a repeat sample detects total <br /> coliforms, the sample will also be analyzed for fecal <br /> coliforms or E. coli. A positive result for fecal coliform or <br /> E. coli samples is an acute MCL violation, which <br /> requires rapid public notification. <br /> State California SWRCB The MCL is based on the number of samples collected <br /> MCL Department of per month. <br /> Drinking Water <br /> (DDW) For systems collecting more than 40 samples per <br /> month, the MCL is exceeded when: <br /> • More than 5% of samples in a month are total <br /> coliform positive <br /> For systems collecting less than 40 samples per month, <br /> the MCL is exceeded when: <br /> • More than 1 sample per month is total coliform <br /> positive <br /> For all systems, regardless of sample size, the MCL is <br /> violated when: <br /> • Any repeat sample is fecal coliform-positive or <br /> E. co/i-positive. <br /> • Any repeat sample following a fecal coliform- <br /> positive or E. coli-positive routine sample is total <br /> coliform-positive. <br /> 1MCLG = Maximum Contaminant Level Goal <br /> 2MPN = Most Probable Number of coliform <br /> Revised September, 2019 2 <br />