350 QUESTIONS AND ANSWERS
1. Q: What is the minimum distance required between a septic tank and a
water well in Virginia? A: 100 feet
2. Q: Who has the authority to issue permits for onsite sewage systems in
Virginia? A: The Virginia Department of Health (VDH) or authorised local
health departments
3. Q: What is the maximum daily flow rate for a conventional onsite sewage
system without special approval? A: 1,000 gallons per day
4. Q: How long is a construction permit valid in Virginia? A: 18 months
from the date of issuance
5. Q: What is the minimum setback distance from a septic tank to a
property line? A: 10 feet
6. Q: Which code governs onsite sewage systems in Virginia? A: Virginia
Sewage Handling and Disposal Regulations (12VAC5-610)
7. Q: What is the minimum distance between a drainfield and a water well?
A: 100 feet
8. Q: Who can perform soil evaluations for onsite sewage systems in
Virginia? A: Licensed soil scientists or professional engineers
9. Q: What is the maximum allowable slope for a drainfield? A: 25% (4:1)
10. Q: How far must a septic tank be from a dwelling? A: Minimum 10 feet
11. Q: What is the minimum distance between a septic tank and a stream?
A: 100 feet
12. Q: What license is required to install onsite sewage systems in Virginia?
A: Onsite Sewage System Installer License (Class I, II, or Master)
13. Q: How often must an installer's license be renewed? A: Every 3 years
,14. Q: What is the minimum distance from a drainfield to a property line?
A: 10 feet
15. Q: Who can design alternative onsite sewage systems? A: Professional
engineers or other qualified professionals approved by VDH
16. Q: What is the minimum distance between a pump tank and a well? A:
100 feet
17. Q: How long does an installer have to complete work after permit
issuance? A: 18 months
18. Q: What is the minimum separation distance between a septic tank and
a swimming pool? A: 25 feet
19. Q: Which agency enforces onsite sewage system regulations in
Virginia? A: Virginia Department of Health
20. Q: What is the maximum allowable percolation rate for a conventional
system? A: 120 minutes per inch
21. Q: How far must a repair area be from the primary drainfield? A:
Minimum 20 feet
22. Q: What is the minimum liquid capacity for a septic tank serving a 3-
bedroom house? A: 1,000 gallons
23. Q: Who must inspect the installation before backfilling? A: A VDH
representative or authorized agent
24. Q: What is the minimum distance from a septic tank to a basement or
crawl space? A: 10 feet
25. Q: How deep must distribution lines be buried? A: Minimum 6 inches,
maximum 18 inches
26. Q: What is the minimum distance between an onsite system and a
public water main? A: 50 feet
27. Q: Who can perform system evaluations for existing systems? A:
Licensed evaluators or qualified professionals
28. Q: What is the maximum depth for a conventional drainfield? A: 48
inches from original grade to bottom of stone
29. Q: How often must alternative systems be inspected? A: At least
annually, or as specified in the permit
, 30. Q: What is the minimum distance from a drainfield to a basement? A:
25 feet
31. Q: Which systems require an operation permit in Virginia? A:
Alternative systems with flows over 1,000 gpd
32. Q: What is the minimum soil depth required below a drainfield? A: 18
inches to groundwater or impermeable layer
33. Q: How far must a septic tank be from a private water supply? A: 100
feet
34. Q: What is the minimum width for distribution trenches? A: 18 inches
35. Q: Who can authorize variances from standard requirements? A: The
Virginia Department of Health
36. Q: What is the maximum spacing between distribution trenches? A: 9
feet on center
37. Q: How long must installation records be maintained? A: 10 years
38. Q: What is the minimum distance from a drainfield to a cut bank? A:
25 feet
39. Q: Which professional must stamp alternative system designs? A: A
Professional Engineer licensed in Virginia
40. Q: What is the minimum liquid depth in a septic tank? A: 30 inches
41. Q: How far must a sand filter be from a property line? A: 10 feet
42. Q: What approval is needed for experimental systems? A: Special
approval from VDH Central Office
43. Q: What is the minimum distance from a pump chamber to a well? A:
100 feet
44. Q: How often must pumpers be licensed? A: Every 3 years
45. Q: What is the minimum clearance above a septic tank? A: 12 inches
46. Q: Which systems require professional design in Virginia? A: Systems
over 1,000 gpd and alternative systems
47. Q: What is the maximum allowable hydraulic loading rate for sand
filters? A: 1.2 gallons per square foot per day
48. Q: How far must a mound system be from a basement? A: 50 feet
1. Q: What is the minimum distance required between a septic tank and a
water well in Virginia? A: 100 feet
2. Q: Who has the authority to issue permits for onsite sewage systems in
Virginia? A: The Virginia Department of Health (VDH) or authorised local
health departments
3. Q: What is the maximum daily flow rate for a conventional onsite sewage
system without special approval? A: 1,000 gallons per day
4. Q: How long is a construction permit valid in Virginia? A: 18 months
from the date of issuance
5. Q: What is the minimum setback distance from a septic tank to a
property line? A: 10 feet
6. Q: Which code governs onsite sewage systems in Virginia? A: Virginia
Sewage Handling and Disposal Regulations (12VAC5-610)
7. Q: What is the minimum distance between a drainfield and a water well?
A: 100 feet
8. Q: Who can perform soil evaluations for onsite sewage systems in
Virginia? A: Licensed soil scientists or professional engineers
9. Q: What is the maximum allowable slope for a drainfield? A: 25% (4:1)
10. Q: How far must a septic tank be from a dwelling? A: Minimum 10 feet
11. Q: What is the minimum distance between a septic tank and a stream?
A: 100 feet
12. Q: What license is required to install onsite sewage systems in Virginia?
A: Onsite Sewage System Installer License (Class I, II, or Master)
13. Q: How often must an installer's license be renewed? A: Every 3 years
,14. Q: What is the minimum distance from a drainfield to a property line?
A: 10 feet
15. Q: Who can design alternative onsite sewage systems? A: Professional
engineers or other qualified professionals approved by VDH
16. Q: What is the minimum distance between a pump tank and a well? A:
100 feet
17. Q: How long does an installer have to complete work after permit
issuance? A: 18 months
18. Q: What is the minimum separation distance between a septic tank and
a swimming pool? A: 25 feet
19. Q: Which agency enforces onsite sewage system regulations in
Virginia? A: Virginia Department of Health
20. Q: What is the maximum allowable percolation rate for a conventional
system? A: 120 minutes per inch
21. Q: How far must a repair area be from the primary drainfield? A:
Minimum 20 feet
22. Q: What is the minimum liquid capacity for a septic tank serving a 3-
bedroom house? A: 1,000 gallons
23. Q: Who must inspect the installation before backfilling? A: A VDH
representative or authorized agent
24. Q: What is the minimum distance from a septic tank to a basement or
crawl space? A: 10 feet
25. Q: How deep must distribution lines be buried? A: Minimum 6 inches,
maximum 18 inches
26. Q: What is the minimum distance between an onsite system and a
public water main? A: 50 feet
27. Q: Who can perform system evaluations for existing systems? A:
Licensed evaluators or qualified professionals
28. Q: What is the maximum depth for a conventional drainfield? A: 48
inches from original grade to bottom of stone
29. Q: How often must alternative systems be inspected? A: At least
annually, or as specified in the permit
, 30. Q: What is the minimum distance from a drainfield to a basement? A:
25 feet
31. Q: Which systems require an operation permit in Virginia? A:
Alternative systems with flows over 1,000 gpd
32. Q: What is the minimum soil depth required below a drainfield? A: 18
inches to groundwater or impermeable layer
33. Q: How far must a septic tank be from a private water supply? A: 100
feet
34. Q: What is the minimum width for distribution trenches? A: 18 inches
35. Q: Who can authorize variances from standard requirements? A: The
Virginia Department of Health
36. Q: What is the maximum spacing between distribution trenches? A: 9
feet on center
37. Q: How long must installation records be maintained? A: 10 years
38. Q: What is the minimum distance from a drainfield to a cut bank? A:
25 feet
39. Q: Which professional must stamp alternative system designs? A: A
Professional Engineer licensed in Virginia
40. Q: What is the minimum liquid depth in a septic tank? A: 30 inches
41. Q: How far must a sand filter be from a property line? A: 10 feet
42. Q: What approval is needed for experimental systems? A: Special
approval from VDH Central Office
43. Q: What is the minimum distance from a pump chamber to a well? A:
100 feet
44. Q: How often must pumpers be licensed? A: Every 3 years
45. Q: What is the minimum clearance above a septic tank? A: 12 inches
46. Q: Which systems require professional design in Virginia? A: Systems
over 1,000 gpd and alternative systems
47. Q: What is the maximum allowable hydraulic loading rate for sand
filters? A: 1.2 gallons per square foot per day
48. Q: How far must a mound system be from a basement? A: 50 feet
