REHS: Wastewater Treatment and Disposal Test Questions and Answers, Latest Update 2024/2025 (100% Verified)

Final disposal of sludge may include all of the following except Choose one answer. a. composting b. sanitary landfill c. land application d. vegetable garden dumping d. vegetable garden dumping A watertight tank designed to slow down the movement of raw sewage and wastes passing through to the soils is known as a Choose one answer. a. pit privy b. spring house c. septic tank d. grease trap c. septic tank Sludge and scum accumulation, and the appearance of particles of solids in the effluent from a septic tank is an indication of what? Choose one answer. a. a failure in the absorption field b. a septic tank in need of cleaning c. a water line leak d. the need to replace the septic tank b. a septic tank in need of cleaning Septage is best defined as Choose one answer. a. sludge b. scum c. gray water d. a mixture of all of the above REHS: Wastewater Treatment and Disposal Test Questions and Answers Latest Update 2024/2025 | 100% Verified d. a mixture of all of the above Trickling filters can remove 90 to 95 percent of the __________ found in soil, water, and wastewater. Choose one answer. a. bacteria b. viruses c. cholera vibrio d. all of the above d. all of the above Yeast added to a new septic tank speeds up digestion by a factor of 2.7. Choose one answer. a. True b. False b. False The ability of the soil to absorb and allow water and air to pass through is called Choose one answer. a. unloading b. infiltration c. permeability d. soil aeration c. permeability Excreta typically is defined as containing Choose one answer. a. 2000 million fecal coliform, 450 million fecal streptococci, and 400 billion E. coli per 100 to 200 grams b. 250 million fecal coliform, 100 million fecal streptococci, and 40 billion E. coli per 550 grams c. significant levels of heavy metals and toxic chemicals d. 400 ppm chlorinated hydrocarbon a. 2000 million fecal coliform, 450 million fecal streptococci, and 400 billion E. coli per 100 to 200 grams The degree of eutrophication of a lake is indicated by Choose one answer. a. the quantity of planktonic algae b. reduced water transparency c. dissolved oxygen in the water near the surface d. all of the above d. all of the above Chemical coagulation, flocculation, sedimentation, and filtration will remove nearly all bacteria, viruses, protozoa, and helminths if supplemented by Choose one answer. a. desalination b. chlorination c. over 4 feet of loamy soil d. all of the above b. chlorination The detention time for wastewater in a septic tank is recommended to be Choose one answer. a. 6 to 12 hours b. 24 to 72 hours c. 1 week d. none of the above b. 24 to 72 hours It is known that some common pathogenic organisms found in wastewater will survive more than __________ of harsh temperature extremes. Choose one answer. a. 2 months b. 5 months c. 2 years d. 5 years c. 2 years 00:0201:11 Human disease from aerosols of wastewater Choose one answer. a. is related primarily to wastewater treatment by the activated sludge, trickling filter, and spray irrigation processes b. has been demonstrated from pathogens recovered in aerosols from the spray irrigation of treated wastewater c. may be caused by very small numbers of organisms d. is a hazard even to those who have had subclinical infections, and thus should have been immunized a. is related primarily to wastewater treatment by the activated sludge, trickling filter, and spray irrigation processes By USEPA Standards, the pH of secondary treatment effluent shall be in the range of Choose one answer. a. 5.5 to 7 b. 5 to 7 c. 7.5 to 10 d. 6 to 9 d. 6 to 9 The permeability of soil is directly related to the __________ of the soil. Choose one answer. a. chemical composition b. color and texture c. granular structure d. all of the above d. all of the above Primary sedimentation can remove __________ found in soil, water, and wastewater. Choose one answer. a. 50 to 90 percent of the bacteria b. 30 to 50 percent of the ascaris c. 80 percent of the schistosomes d. all of the above d. all of the above Ozone disinfection has many advantages. Which of the following is NOT true? Choose one answer. a. ozone is non-toxic to aquatic organisms b. ozone can be a source of dissolved oxygen c. ozone is a good viricide d. ozone is approximately equal in cost to chlorine d. ozone is approximately equal in cost to chlorine In the usage of septic-tank additives, which of the following compounds is not recommended? Choose one answer. a. sulfuric acid b. methylene chloride c. trichloroethane d. all of the above d. all of the above While it is arguably preferable to conduct a soil analysis for sizing absorption fields percolation tests are sometimes used. In order to obtain reproducible results with a soil percolation test, it is very important to: Choose one answer. a. add at least 2 inches of gravel to the bottom of the test pit b. cross-reference results with reliable soil maps c. soak the hole with water before the test is made d. repeat the test or use dual pits c. soak the hole with water before the test is made The sand filter is used to Choose one answer. a. remove suspended solids from water b. remove bacteria from water c. sterilize water d. a and b above d. a and b above The placement of the distribution box is not critical as long as it is water tight. Choose one answer. a. True b. False b. False Loam is composed of which of the following? Choose one answer. a. sand b. gravel c. silt d. all of the above d. all of the above Why is the proper disposal of sewage necessary? Choose one answer. a. it reduces illness in the population b. it provides comfort for individuals c. it reduces the pollution of surface groundwater d. all of the above d. all of the above The septic tank functions as a Choose one answer. a. a biological treatment system b. a sedimentation tank c. a conditioning tank d. all of the above d. all of the above The wastewater from a toilet or latrine flushing is referred to as Choose one answer. a. gray water b. black water c. green water d. red water b. black water The effectiveness of disinfection depends on Choose one answer