WEST VIRGINIA SEPTIC INSTALLER (CLASS I & II) 2026/2027 | 100%
VERIFIED EXAM QUESTIONS AND CORRECT ANSWERS | LATEST UPDATED
WV Septic Installers
1. Question: No part of an individual sewage system location shall be within how
many feet of a building, foundation, or property line? ANSWER : 10 feet.
2. Question: No part of an individual sewage system location shall be within how
many feet of a public water supply line? ANSWER : 25 feet.
3. Question: No part of an individual sewage system location shall be within how
many feet of a private water supply line? ANSWER : 10 feet.
4. Question: What is the minimum required vertical separation, in feet, between
any portion of a standard soil absorption system and seasonal groundwater,
bedrock, or any other impermeable layer? ANSWER : 3 feet.
5. Question: A standard septic tank soil absorption system cannot be installed in
soils where percolation test results show an average percolation time of less
than how many minutes per inch? ANSWER : 5 minutes per inch.
6. Question: What is the minimum number of test holes required for a percolation
(perc) test? ANSWER : 4 test holes.
7. Question: During a perc test, the test hole must be maintained at a depth of at
least how many inches for what minimum period of time before beginning
measurements? ANSWER : 12 inches for a minimum of 4 hours.
8. Question: For a dwelling with four or fewer bedrooms, what is the minimum
tank capacity required, and how many additional gallons are required for each
bedroom beyond four? ANSWER : 1,000 gallons for four bedrooms and 250
gallons for each additional bedroom.
9. Question: When using a dual compartment tank or dual tanks, what is the
required volume ratio of the first compartment to the second? ANSWER :
Approximately 2 to 1.
10.Question: The inlet of a septic tank must be equipped with a baffle or sanitary
tee that extends to what minimum depth? ANSWER : 6 inches.
11.Question: The inlet baffle or sanitary tee shall extend no more than what
percentage of the liquid depth? ANSWER : 20%.
, 12.Question: To what percentage of the liquid depth must the effluent baffle
extend? ANSWER : At least 35%, but no more than 40% of the liquid depth.
13.Question: What is the minimum allowable liquid depth in a septic tank?
ANSWER : 30 inches.
14.Question: What is the minimum required clearance, in inches, above the liquid
level in a septic tank? ANSWER : 9 inches.
15.Question: What are the required width and depth dimensions for absorption
trenches? ANSWER : 1 to 3 feet wide, with a maximum depth of 36 inches
and a minimum depth of 18 inches.
16.Question: What is the minimum amount of aggregate required below and above
the absorption field piping? ANSWER : 6 inches of aggregate beneath the pipe
and 2 inches above the pipe.
17.Question: The invert of the absorption field piping must be a minimum of how
many inches lower than the invert of the sewage tank outlet? ANSWER : 8
inches.
18.Question: What is the minimum required ground cover over the gravel fill in
each absorption trench? ANSWER : 6 inches.
19.Question: The invert of the overflow pipe in the first relief or cross-over line
should be at least how many inches lower than the invert of the septic tank
outlet? ANSWER : 2 inches.
20.Question: Absorption fields exceeding what total area in square feet are
required to include some form of dosing? ANSWER : 3,000 square feet.
21.Question: If the soil absorption field is greater than what square footage may
the Commissioner require a siphon or pump chamber to ensure even
distribution? ANSWER : 1,500 square feet.
22.Question: When a total field area exceeds how many square feet must the field
be split into two or more fields of approximately equal size? ANSWER : 5,000
square feet.
23.Question: To account for sidewall loss, how much larger must an absorption
bed be compared to the area calculated for a standard absorption field?
ANSWER : 30% greater.
24.Question: What is the maximum length allowed for any single lateral in a
gravity-fed absorption field? ANSWER : 100 feet.
25.Question: What is the minimum required distance between the bottom of a
septic tank and the groundwater table or bedrock? ANSWER : 1 foot.
VERIFIED EXAM QUESTIONS AND CORRECT ANSWERS | LATEST UPDATED
WV Septic Installers
1. Question: No part of an individual sewage system location shall be within how
many feet of a building, foundation, or property line? ANSWER : 10 feet.
2. Question: No part of an individual sewage system location shall be within how
many feet of a public water supply line? ANSWER : 25 feet.
3. Question: No part of an individual sewage system location shall be within how
many feet of a private water supply line? ANSWER : 10 feet.
4. Question: What is the minimum required vertical separation, in feet, between
any portion of a standard soil absorption system and seasonal groundwater,
bedrock, or any other impermeable layer? ANSWER : 3 feet.
5. Question: A standard septic tank soil absorption system cannot be installed in
soils where percolation test results show an average percolation time of less
than how many minutes per inch? ANSWER : 5 minutes per inch.
6. Question: What is the minimum number of test holes required for a percolation
(perc) test? ANSWER : 4 test holes.
7. Question: During a perc test, the test hole must be maintained at a depth of at
least how many inches for what minimum period of time before beginning
measurements? ANSWER : 12 inches for a minimum of 4 hours.
8. Question: For a dwelling with four or fewer bedrooms, what is the minimum
tank capacity required, and how many additional gallons are required for each
bedroom beyond four? ANSWER : 1,000 gallons for four bedrooms and 250
gallons for each additional bedroom.
9. Question: When using a dual compartment tank or dual tanks, what is the
required volume ratio of the first compartment to the second? ANSWER :
Approximately 2 to 1.
10.Question: The inlet of a septic tank must be equipped with a baffle or sanitary
tee that extends to what minimum depth? ANSWER : 6 inches.
11.Question: The inlet baffle or sanitary tee shall extend no more than what
percentage of the liquid depth? ANSWER : 20%.
, 12.Question: To what percentage of the liquid depth must the effluent baffle
extend? ANSWER : At least 35%, but no more than 40% of the liquid depth.
13.Question: What is the minimum allowable liquid depth in a septic tank?
ANSWER : 30 inches.
14.Question: What is the minimum required clearance, in inches, above the liquid
level in a septic tank? ANSWER : 9 inches.
15.Question: What are the required width and depth dimensions for absorption
trenches? ANSWER : 1 to 3 feet wide, with a maximum depth of 36 inches
and a minimum depth of 18 inches.
16.Question: What is the minimum amount of aggregate required below and above
the absorption field piping? ANSWER : 6 inches of aggregate beneath the pipe
and 2 inches above the pipe.
17.Question: The invert of the absorption field piping must be a minimum of how
many inches lower than the invert of the sewage tank outlet? ANSWER : 8
inches.
18.Question: What is the minimum required ground cover over the gravel fill in
each absorption trench? ANSWER : 6 inches.
19.Question: The invert of the overflow pipe in the first relief or cross-over line
should be at least how many inches lower than the invert of the septic tank
outlet? ANSWER : 2 inches.
20.Question: Absorption fields exceeding what total area in square feet are
required to include some form of dosing? ANSWER : 3,000 square feet.
21.Question: If the soil absorption field is greater than what square footage may
the Commissioner require a siphon or pump chamber to ensure even
distribution? ANSWER : 1,500 square feet.
22.Question: When a total field area exceeds how many square feet must the field
be split into two or more fields of approximately equal size? ANSWER : 5,000
square feet.
23.Question: To account for sidewall loss, how much larger must an absorption
bed be compared to the area calculated for a standard absorption field?
ANSWER : 30% greater.
24.Question: What is the maximum length allowed for any single lateral in a
gravity-fed absorption field? ANSWER : 100 feet.
25.Question: What is the minimum required distance between the bottom of a
septic tank and the groundwater table or bedrock? ANSWER : 1 foot.
