Illinois Private Sewage Contractor
Ultimate Exam
**Question 1.** Which term describes wastewater that originates from
household activities such as laundry, dishwashing, and toilet flushing?
A) Industrial effluent
B) Domestic sewage
C) Stormwater runoff
D) Agricultural runoff
Answer: B
Explanation: Domestic sewage is the wastewater generated from residential
activities, including toilets, sinks, showers, and appliances.
**Question 2.** In Illinois Private Sewage regulations, the “limiting layer” refers
to:
A) The topsoil layer that must be removed before trenching
B) A soil horizon that restricts percolation rates below a specified minimum
C) The layer of aggregate used beneath distribution pipes
D) The concrete slab over a septic tank
Answer: B
Explanation: A limiting layer is a soil or rock stratum that slows infiltration, often
requiring alternative designs or variances.
**Question 3.** The “effective size” of a soil particle is defined as:
A) The diameter of the largest particle present in a sample
, Illinois Private Sewage Contractor
Ultimate Exam
B) The size at which 10% of the soil mass is finer by weight
C) The average particle size measured by sieve analysis
D) The size of the particle that controls hydraulic conductivity
Answer: B
Explanation: Effective size (D₁₀) is the particle diameter at which 10% of the soil
sample is finer, used in permeability calculations.
**Question 4.** “Population Equivalent (PE)” is used to:
A) Estimate the number of people a septic system can serve based on BOD load
B) Determine the depth of a septic tank
C) Calculate the required number of distribution boxes
D) Set the minimum setback distance from a well
Answer: A
Explanation: PE converts wastewater flow into an equivalent number of persons,
based on a standard BOD₅ load of 60 g/day.
**Question 5.** Under the Private Sewage Disposal Licensing Act, a contractor
must provide a bond of at least:
A) $5,000
B) $10,000
C) $25,000
D) $50,000
, Illinois Private Sewage Contractor
Ultimate Exam
Answer: C
Explanation: Illinois law requires a minimum $25,000 bond to ensure financial
responsibility for corrective actions.
**Question 6.** Failure to obtain a required permit before constructing a septic
system can result in:
A) A verbal warning only
B) A civil penalty of up to $5,000 per day
C) Immediate system shutdown without notice
D) Mandatory system redesign at the contractor’s expense
Answer: B
Explanation: Non-compliance can lead to civil penalties, often up to $5,000 per
day, and possible legal action.
**Question 7.** When requesting a variance due to an excessive water table, the
applicant must submit:
A) Only a site photograph
B) A detailed soil report, percolation test results, and a design alternative
C) A signed affidavit stating the condition exists
D) No documentation; the variance is granted automatically
Answer: B
, Illinois Private Sewage Contractor
Ultimate Exam
Explanation: Variance requests require comprehensive documentation to
demonstrate why standard code cannot be met.
**Question 8.** The proper procedure for a percolation test includes which of
the following steps?
A) Digging a 12-inch diameter hole, filling it with water, and timing the first 30
seconds only
B) Preparing a 6-inch diameter hole, presoaking for 24 hours, then recording the
drop over a 30-minute period
C) Using a 4-inch diameter hole, no soaking, and measuring the time for water to
disappear completely
D) Conducting the test only after the trench is backfilled
Answer: B
Explanation: Illinois percolation testing requires a 6-inch hole, a 24-hour presoak,
and measurement of water level drop at specified intervals.
**Question 9.** Minimum soil borings required for a new septic system in Illinois
are:
A) One boring per acre
B) Two borings spaced 30 ft apart
C) Three borings, each at least 50 ft apart within the system area
D) Five borings, regardless of area size
Answer: C
Ultimate Exam
**Question 1.** Which term describes wastewater that originates from
household activities such as laundry, dishwashing, and toilet flushing?
A) Industrial effluent
B) Domestic sewage
C) Stormwater runoff
D) Agricultural runoff
Answer: B
Explanation: Domestic sewage is the wastewater generated from residential
activities, including toilets, sinks, showers, and appliances.
**Question 2.** In Illinois Private Sewage regulations, the “limiting layer” refers
to:
A) The topsoil layer that must be removed before trenching
B) A soil horizon that restricts percolation rates below a specified minimum
C) The layer of aggregate used beneath distribution pipes
D) The concrete slab over a septic tank
Answer: B
Explanation: A limiting layer is a soil or rock stratum that slows infiltration, often
requiring alternative designs or variances.
**Question 3.** The “effective size” of a soil particle is defined as:
A) The diameter of the largest particle present in a sample
, Illinois Private Sewage Contractor
Ultimate Exam
B) The size at which 10% of the soil mass is finer by weight
C) The average particle size measured by sieve analysis
D) The size of the particle that controls hydraulic conductivity
Answer: B
Explanation: Effective size (D₁₀) is the particle diameter at which 10% of the soil
sample is finer, used in permeability calculations.
**Question 4.** “Population Equivalent (PE)” is used to:
A) Estimate the number of people a septic system can serve based on BOD load
B) Determine the depth of a septic tank
C) Calculate the required number of distribution boxes
D) Set the minimum setback distance from a well
Answer: A
Explanation: PE converts wastewater flow into an equivalent number of persons,
based on a standard BOD₅ load of 60 g/day.
**Question 5.** Under the Private Sewage Disposal Licensing Act, a contractor
must provide a bond of at least:
A) $5,000
B) $10,000
C) $25,000
D) $50,000
, Illinois Private Sewage Contractor
Ultimate Exam
Answer: C
Explanation: Illinois law requires a minimum $25,000 bond to ensure financial
responsibility for corrective actions.
**Question 6.** Failure to obtain a required permit before constructing a septic
system can result in:
A) A verbal warning only
B) A civil penalty of up to $5,000 per day
C) Immediate system shutdown without notice
D) Mandatory system redesign at the contractor’s expense
Answer: B
Explanation: Non-compliance can lead to civil penalties, often up to $5,000 per
day, and possible legal action.
**Question 7.** When requesting a variance due to an excessive water table, the
applicant must submit:
A) Only a site photograph
B) A detailed soil report, percolation test results, and a design alternative
C) A signed affidavit stating the condition exists
D) No documentation; the variance is granted automatically
Answer: B
, Illinois Private Sewage Contractor
Ultimate Exam
Explanation: Variance requests require comprehensive documentation to
demonstrate why standard code cannot be met.
**Question 8.** The proper procedure for a percolation test includes which of
the following steps?
A) Digging a 12-inch diameter hole, filling it with water, and timing the first 30
seconds only
B) Preparing a 6-inch diameter hole, presoaking for 24 hours, then recording the
drop over a 30-minute period
C) Using a 4-inch diameter hole, no soaking, and measuring the time for water to
disappear completely
D) Conducting the test only after the trench is backfilled
Answer: B
Explanation: Illinois percolation testing requires a 6-inch hole, a 24-hour presoak,
and measurement of water level drop at specified intervals.
**Question 9.** Minimum soil borings required for a new septic system in Illinois
are:
A) One boring per acre
B) Two borings spaced 30 ft apart
C) Three borings, each at least 50 ft apart within the system area
D) Five borings, regardless of area size
Answer: C
