ABC Wastewater Level 3 – Lab Exam Questions with 100% correct answers

To have significant meaning for laboratory tests of the evaluation of a wastewater treatment plant's performance the best method of sampling is A. Grab sampling B. Hourly sampling C. Sampling during peak flow D. Proportional composite sampling E. Automatic sampling - correct answer D. Proportional composite sampling BOD samples should be collected before chlorination because A. Chlorine reacts with the buffer solution B. Chlorine interferes with the activity of organisms C. Chlorine reacts with the calcium ions D. Chlorine affects the alkalinity - correct answer B. Chlorine interferes with the activity of organisms A water sample is "fixed" in the field by A. Keeping the sample in a Cipolletti device B. Anchoring the container to the stream bed C. Adding chemicals to prevent the changing of water quality D. Maintaining a constant sample temperature of 95° F - correct answer C. Adding chemicals to prevent the changing of water quality