Wastewater Treatment Operator Certification Practice Exam #2 Questions 100% Answered!!

Wastewater Treatment Operator Certification Practice Exam #2 Questions 100% Answered!!What is true about chlorine gas? - ANSWERIt is 2.5 times heavier than air What is the typical BOD removal efficiency in a primary clarifier? - ANSWER20 to 50% What does the "F" in F/M ratio represent? - ANSWERThe food for the microorganisms flowing into the aeration tank, in lbs/day What describes the appearance of healthy activated sludge? - ANSWERBrown with a moderate amount of crisp, white foam What is used to control filamentous organisms? - ANSWERChlorine What are commonly used to control chlorine feed rate for disinfection? - ANSWERFlow and chlorine residual Which toxic gas is commonly found in septic wastewater and smells like rotten eggs? - ANSWERHydrogen sulfide What is the permissible exposure limit for chlorine gas vapor during a normal 8-hour workday and a 40-hour workweek? - ANSWER0.5 ppm What is a vulnerability assessment? - ANSWERContingency planning to determine the vulnerability of the utility during various types of emergencies and identify corrective actions to reduce the risks What is the difference between the settling rate of activated sludge and raw sludge? - ANSWERActivated sludge settles slower than raw sludge What should be mostly found in healthy activated sludge? - ANSWERFree-swimming and stalked ciliates One to two percent of the digester gas in an anaerobic digester consists of: - ANSWERHydrogen, nitrogen, hydrogen sulfide and other gases