Accurate Answers
which agency sets legal limits on the concentration levels of harmful contaminants in
potable water distributed to customers? - ANSWER-US Environmental Protection
Agency
The number of monthly distribution system bacteriological samples required is -
ANSWER-Based on population served
what is the maximum contaminant level for total trihalomethanes (TTHM) in the US?
- ANSWER-0.080 mg/L
under the Surface Water Treatment rule disinfection residuals must be collected at
the same location in the distribution system as - ANSWER-coliform samples
Iron can cause "red water" and thus customer complaints when its concentration is
above its secondary maximum contaminant level of - ANSWER-0.30 mg/L
The goal of the Surface Drinking water act for each ___________ to accept primary
enforcement responsibility (primacy) for the operation of the state's drinking water
program? - ANSWER-state
What is the objective of the Total Coliform Rule? - ANSWER-To promote routine
surveillance of distribution system water quality to search for fecal matter and/or
disease-causing bacteria
Which agency sets standards on the concentration levels of harmful contamination in
drinking water? - ANSWER-US Environmental Protection Agency
Explain the difference between the different tiers of violations. Which one is the most
serious? - ANSWER-Tier 1is an acute MCL violation requiring public notification
within 24 hours. Tier 2 notification must occur within 30 days. Tier 3 requires
notification within one year.
A positive E. coli test must be reported to the primacy health agency within what time
period? - ANSWER-24 Hours
How is the required number of monthly bacteriological samples determined? -
ANSWER-Populations served
What is the action level for lead in first-draw samples taken from customer taps? -
ANSWER-0.015 mg/L