kceh ww

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  1. The suitability of soil for the subsurface disposal of sewage and other wastewater can be determined by a study of soil characteristics and the
    soil percolation test
  2. Septic tanks serving commercial operations should be inspected for the need for cleaning
    twice per year
  3. The placement of the distribution box is not critical as long as it is water tight.

    a. True                                 
    b. False
    b.  false
  4. Sludge and scum accumulation, and the appearance of particles of solids in the effluent from a septic tank is an indication of what?
    a septic tank in need of cleaning
  5. Chlorination of untreated wastewater is typically NOT an effective treatment for
    • -entamoeba histolytica cysts
    • -giardia cysts
    • -tapeworm eggs
  6. Common causes of failure of septic tank seepage field systems include improper sizing, nonsuitable soil, nonservicing, and
    leaking fixtures
  7. The septic tank functions as a
    • -a biological treatment system
    • -a sedimentation tank
    • -a conditioning tank
  8. The typical limitation of use of the septic tank absorption field system is due to
    soil type and size requirements
  9. The sand filter is used to
    • -remove suspended solids from water
    • -remove bacteria from water
  10. Sewage treatment plants should be designed for
    the population at least 10 years in the future
  11. Facultative bacteria can
    live under both aerobic and anaerobic condition
  12. The volume of the dose from a properly sized dosing tank should be equal to:
    60% of the volume of the lines dosed
  13. Why is the proper disposal of sewage necessary?
    • -it reduces illness in the population
    • -it provides comfort for individuals
    • -it reduces the pollution of surface groundwater
  14. The field distribution piping should be surrounded with ______ and at least 2 inches deep under the pipe.
    -washed gravel, 3/4 inches to 2 1/2 inches
  15. The distance between the field lines or tiles must be a minimum of ______ in a treatment absorption field arrangement.
    -6 feet
  16. The NODAK system (original mound system) is designed to
    protect ground water
  17. Stream pollution is sometimes apparent by
    a zone of degradation
  18. The ability of the soil to absorb and allow water and air to pass through is called
  19. Grease traps are installed for the purpose of minimizing grease in the sewer system.  The trap
    is not of proven value in many commercial applications
  20. The detention time for wastewater in a septic tank is recommended to be
    24 to 72 hours
  21. A water leak no larger than 1/8 inch in diameter can result in a loss of up to:
    400 gallons in 24 hours
  22. In the usage of septic-tank additives, which of the following compounds is not recommended?

    -sulfuric acid
    -methylene chloride
    -all of the above
    -all of the above
  23. If a septic tank is pumped in a wet period
    the tank may begin to float
  24. The depth of septic tanks and ratio of width to length recommended by most health departments are very similar.

    a. False
    b. True
    b. True
  25. The recommended backfill over the absorption field is 8 to12 inches.

    a. True
    b. False
    a. True
  26. Ozone disinfection has many advantages.  Which of the following is NOT true?

    A. ozone can be a source of dissolved oxygen
    B. ozone is a good viricide
    C. ozone is non-toxic to aquatic organisms
    D. ozone is approximately equal in cost to chlorine
    D. ozone is approximately equal in cost to chlorine
    (this multiple choice question has been scrambled)
  27. After a septic tank has been cleaned, it should not be scrubbed and disinfected.  Why?
    a. the sludge sticking to the insides would have a seeding effect and assist in renewing the bacterial activity

    c. it would be considered a safety hazard
  28. The recommended maximum length of the system materials for a gravity flow absorption field is 75 feet.

    a. True
    b. False
    a. True
  29. Low-pressure, vacuum and cluster systems may be used
    • a. where soil is unsuitable for septic-tank systems
    • b. in hilly areas
    • c. in high-density recreational areas
  30. The amount of dissolved oxygen required in aerobic bacterial decomposition, measured in ppm or mg/l and used in determining the strength of wastewater is
    c. biochemical oxygen demand
  31. The ability of a soil to absorb and allow water and air to pass through is related to all of the following except

    A. cation exchange capacity
    B. granular structure
    C. texture
    D. chemical composition
    A. cation exchange capacity
    (this multiple choice question has been scrambled)
  32. Primary sedimentation can remove __________ found in soil, water, and wastewater
    • a. 50 to 90 percent of the bacteria
    • b. 30 to 50 percent of the ascaris
    • c. 80 percent of the schistosomes
  33. The top of the absorption field gravel should be covered with
    b. permeable material
  34. Any excavation in clay, loam, silt or sand more than ______ in depth should have side wall protection to prevent a cave-in.
    b. 4 feet
  35. Bacteria that get their oxygen from the air are called
    b. aerobic bacteria
  36. Nutrients associated with eutrophication include
    • a. phosphates
    • b. nitrogen
    • c. organic carbon
  37. Man-made organic compounds that degrade very slowly are referred to as
    refractory organics
  38. What is the best assurance of satisfactory operation of a properly designed and constructed septic tank system?
    a. proper maintenance
  39. Why should sewage sludge not be used as a soil builder or fertilizer supplement for crops for forage if it has not been properly tested?
    b. it may result in higher levels of toxic metals in the vegetation and in the animals eating the vegetation
  40. Chemical coagulation, flocculation, sedimentation, and filtration remove
    • a. most bacteria
    • b. most viruses and protozoa
    • c. most helminths
  41. After the absorption field has failed, which of the following will NOT correct or repair the field?
    b. increase the water pressure
  42. 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:
    c. soak the hole with water before the test is made
  43. Which of the following would be a cause of septic-tank failure?
    • a. lack of routine cleaning of the septic tank
    • b. leaking plumbing fixtures
    • c. improper design and construction of the absorption system
  44. Which of the following is not true concerning sewage and disease hazards?
    b. entamoeba histolytica, hepatitis viruses, and giardia cysts are easily destroyed by normal chlorination of sewage
  45. Loam is a mixture of gravel, sand, silt, and clay containing what?
    decayed plant and animal matter
  46. The plans for an area to be sewered should
    • a. be prepared by a licensed professional engineer
    • b. include specifications and an engineering report
    • c. include the problem, objectives and design details
  47. Wastewater is the used water from a home or community and the strength is expressed in terms of
    • a. BOD
    • b. COD
    • c. suspended solids
  48. The permeability of soil is directly related to the __________ of the soil
    • a. chemical composition
    • b. color and texture
    • c. granular structure
  49. Disinfection or chlorination of sewage effluent is
    c. an added safeguard to reduce the risk of disease transmission where the probability exists
  50. Yeast added to a new septic tank speeds up digestion by a factor of 2.7.

    a. True
    b. False
    b. False
  51. It is known that some common pathogenic organisms found in wastewater will survive more than __________ of harsh temperature extremes.
    c. 2 years
  52. The wastewater from a toilet or latrine flushing is referred to as
    b. black water
  53. Trickling filters can remove 90 to 95 percent of the __________ found in soil, water, and wastewater.
    • a. bacteria
    • b. viruses
    • c. cholera vibrio
  54. Chemical coagulation, flocculation, sedimentation, and filtration will remove nearly all bacteria, viruses, protozoa, and helminths if supplemented by
    b. chlorination
  55. Which of the following is typically used at a residential sewage treatment system with a surface discharge?

    a. sodium hypochlorite
    b. calcium hypochlorite
    c. liquid chlorine
    d. a or b above
    d. a or b above
  56. A lump of soil with good characteristics will break apart with little pressure along definite cleavage plains and should be blue or grayish in color.

    a. True
    b. False
    b. False
  57. If the septic tank will have a garbage disposal unit feeding into it
    a. the size of the tank should be increased 50 percent
  58. The exposure of excreta or sewage on the surface of the ground sets the stage for disease transmission by both direct contact or
    • a. indirect contact
    • b. vector
    • c. vehicle or fomite
  59. Which of the following are least important in reducing sewage to "soil," liquids, and gases?
    a. anaerobic bacteria
  60. The reliability and interpretation of the soil percolation test are affected by all of the following except

    A. evaluation of site investigation, soil profile, and suitability
    B. saturation of soil
    C. size or diameter of the test hole
    D. shape of the test hole
    D. shape of the test hole
    (this multiple choice question has been scrambled)
  61. Which of the following is true regarding the use of septic-tank cleaners?

    A. the greasing compounds used have proven to be completely safe
    B. their use is not advised
    C. there is no evidence that the chemicals used eventually reach groundwater
    D. additives have been shown to be cost-effective alternatives to annual cleaning
    B. their use is not advised
    (this multiple choice question has been scrambled)
  62. The recommended distance from the bottom of the trench to the ground water table or rock is 62 inches.

    a. True
    b. False
    b. False
  63. Brine from water softening units as low as ______ may inhibit bacterial action in septic tanks.
    a. 1.2 percent
  64. Excreta typically is defined as containing
    a. 2000 million fecal coliform, 450 million fecal streptococci, and 400 billion E. coli per 100 to 200 grams
  65. How often should a septic tank for a private home be serviced?
    c. every 3 to 5 years
  66. Which of the following is non-toxic to aquatic organisms, a good viricide, and adds oxygen to treated wastewater effluents?
    a. ozone
  67. The use of a cesspool is prohibited due to
    d. greater potential for groundwater contamination
  68. A young lake is considered to be
    c. oligotrophic
  69. The National Pollutant Discharge Elimination System (NPDES) prohibits the discharge of pollutants into U.S. waters unless a permit is issued by
    a. EPA


    b. the State
  70. The favored method of disposal of domestic wastewater is
    d. connection to public sewer system
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