Basic water works operations exam Questions and Complete Solutions.

Basic water works operations exam Questions and Complete Solutions How long must a water system save their bacteriological test results? - Answer: 5 years Which of the following would be classified as a community type public water system? - Answer: Mobile home park Which of the following agencies is responsible for regulating drinking water standards in the state of Texas? - Answer: TCEQ The utility employee with the most frequent contact with the customer is the? - Answer: Meter reader Community water systems are required to provide customers with a yearly report on the system's water quality called the? - Answer: Consumer confidence report Helpful, informative handouts sometimes included in water bills are called? - Answer: Stuffers The process of the water moving between the earth and the atmosphere is called the? - Answer: Hydrologic cycle The current limits on turbidity in filtered water are? - Answer: < or =0.3 NTU'S The 2 main minerals that cause hardness in water are? - Answer: Calcium and magnesium Water-bearing formations below the earth's surface are called? - Answer: Aquifers All public water well may not have any source of contamination within? - Answer: 50 feet Before putting a well into service,it must be disinfected by chlorination to a level of? - Answer: 50mg/L for 6hours The particles formed after coagulation are called? - Answer: Floc The particles that settle to the bottom of a clarifier firm into? - Answer: Sludge The final step in removing solids in surface water treatment is? - Answer: Filtration Waterborne disease causing organisms are called? - Answer: Pathogens According to the rules and regulations for public water systems, a public water supply using chlorine as the distribution disinfectant must maintain a free chlorine residual of what in the far reaches of the system? - Answer: 0.2 mg/L The most superior chemical in oxidizing taste, odor, color, iron,manganese, or organics in water is? - Answer: Ozone Water systems are required to have a storage capacity of how many gallons per connection? - Answer: 200 What psi is created by 1 foot column of water? - Answer: 0.433 Which pump type is the most commonly used by the water utilities industry? - Answer: Centrifugal What is the percentage of oxygen in normal air? - Answer: 20.9 What is the number 1 cause of death in confined spaces? - Answer: Lack of oxygen All excavations deeper that how many feet require cave-in protection? - Answer: 5 A rectangular storage tank is 40 feet long,25 feet wide, and 10 feet deep. What is the volume in cubic feet? And how many gallons the tank will hold when full? - Answer: 10000/74800 A clarifier is 60 feet in diameter and 12 feet deep. What is the volume in cubic feet? And what is volume in gallons when full? - Answer: 33912/253661 A sedimentation tank is 75 feet long,35 feet wide and 15 feet deep. What is the detention time in hours at a flow rate of 2 mgd? - Answer: 3.5