During construction of a water main system, one way to reduce contamination of the pipes is to
. Place them at the bottom of the trench while connecting joints Avoid storing pipes at the construction site for long periods Maintain good air circulation by keepinj pipes open when work stops for A B. C.
the day D. Wait until the pipeline is nearly completed before swabbing interior surfaces
When taking samples for biological testing, collect water at the end of the pipe- line and every _____ feet along the line.
After treating a mainline that was contaminated with trench water during con- struction or repair, how much time must pass after flushing before you take samples for biological testing?
Which of the following steps might fail to reveal unsafe levels of chlorine in a pipeline?
. Using testing equipment suitable only for the concentration ranges being measured
Repeating test more frequently than recommended
Calibrating testing equipment more frequently than recommended
Using the same batch of chemical reagents until it is depleted to assure con-
sistency for all testing
For information and techniques to use for sanitizing potable water pipes, consult the
Department of Pesticide Regulation
American Water Works Association and state and local guidelines
County agricultural commissioner’s office
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