The concentration of a contaminant, which, if exceeded, triggers treatment or other requirements which a water system must follow. More than or equal to Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. By-Product of Drinking Water Chlorination. Total Trihalomethanes is the sum of chloroform, bromodichloromethane, dibromochloromethane, and bromoform.
Compliance is based on the total.
New MCL effective December 16, 2001. We monitor it because it is a good indicator of the effectiveness of our filtration system. A routine sample and a repeat sample are total coliform positive, and one is also fecal or E.coli positive. Leaching from wood preservatives. The 90th percentile value means 90 percent of the homes tested have lead and copper levels below the given 90th percentile value.