Water Distribution Exam Sample Text Questions Correct 100%

What is the federal law that protects public water supplies from harmful contaminants? - Answer SDWA Safe Drinking Water Act MCL stands for - Answer Maximum Contaminant Level True or False? Primary regulations are mandatory - Answer TRUE Secondary regulations are about what 3 things? - Answer Taste Odor Color of water True or False? Secondary regulations are mandatory - Answer FALSE What is the minimum pressure that must be maintained at all times in a distribution system? - Answer 20 PSI The limit for velocity in a system is? - Answer 5 ft/sec The spoil pile should be located how far back from the trench wall? - Answer 2 feet (min) True or False? A vent in a chlorine room should be located near the ceiling. - Answer FALSE An area is considered unsafe when the oxygen level drops to below a) 19.5% b) 20.2% c) 10.5% d) 19.25% - Answer a) 19.5% The most common valve used in a distribution system is a) butterfly b) gate c) ball d) check - Answer b) gate A chain of custody is required for a sample a) from collection to disposal b) from collection to the lab c) from the lab to disposal d) all of the above - Answer b) from the collection to the lab 1 (one) cubic foot of water is _____ lbs a) 7.48 b) 8.34 c) 27 d) 62.38 - Answer d) 62.38 How should a CL2 (chlorine) storage room be vented? a) mechanically at the floor b) mechanically at the ceiling c) in the middle of the wall d) no ventilation is required - Answer a) mechanically at the floor If a chlorine leak develops in a room where you are working, you should a) quickly leave the room b) crawl on the floor and quickly leave the room c) close your mouth, hold your head as high as possible and quickly leave the room d) call 911, then leave the room - Answer c) close your mouth, hold your head as high as possible and quickly leave the room a beard could prevent proper use of what safety equipment? a) goggles b) fire extinguisher c) SCBA d) Safety Vest - Answer SCBA (self contained breathing apparatus) Prior to entering a storage tank you should a) Throw a match in the tank to check for explosive gas b) mechanically blow air into the tank c) Do nothing, just go ahead and enter the tank d) notify your supervisor then carefully proceed - Answer b) mechanically blow air into the tank. When using a fire hydrant, it should be a) fully open b) half way closed c) closed - Answer a) fully open As defined by the regulatory agency or rule, free chlorine (CL2) is a) the amount of chlorine left after the demand is met b) the sum of the demand and the residual c) the amount of chlorine in the entire distribution system - Answer a) the amount of chlorine left after the demand is met A water tap should be installed on the main at this angle - Answer 45 degrees What type of valve would be used to control the level in an elevated storage tank? a) gate valve b) ball valve c) altitude valve d) check valve - Answer c) altitude valve