N.H. Code Admin. R. Env-Wq 1008.05 – Minimum Distances

(a) The minimum separation distance in feet between components of an ISDS and the identified receptors shall be as specified in Table 1008-2, subject to (b) through (e), below:
Table 1008-2: Minimum Separation Distances (in Feet)
Component→
Receptor↓
Septic Tank and Pump Chamber
Bed
Sewer Line
Surface Water
75
75
Boundary of Wetlands with Poorly Drained Soils
50
50
Boundary of Wetlands with Very Poorly Drained Soils
75
75
Watercourse, intercepting SHWT
75
75
Watercourse, not intercepting SHWT
25
35
Culvert With Sealed Pipe Joints
10
25
Catch Basin, Culvert without sealed pipe joints, or Foundation drain outfall
25
25
Water Mains and Water Service Lines, pressurized
10
10
10
Water Service Lines, suction
50
50
50
Property Boundaries
5
10
5
Foundation, any type, with Foundation Drains
5
15
Foundation, full basement, without Foundation Drains
5
10
Foundation, slab, without Foundation Drains
5
5
Foundation Drains Outfall Pipe (Solid)
5
5
Top of Natural Embankment or Natural Steep Slope
5
20
Stormwater Pond intercepting SHWT
50
75
Stormwater Pond not intercepting SHWT
25
35
Geothermal well, open loop
75
75
Geothermal well, closed loop
25
25
Drainage ditch or drainage swale, upgradient of bed, does not intercept SHWT
10
10
Drainage ditch or interceptor drain (for example a curtain drain), upgradient of bed, intercepting SHWT
10
25
Swimming pool, in-ground, downgradient of bed
15
Swimming pool, in-ground, upgradient or side gradient of bed
10
(b) The distance between a septic tank and surface water, watercourse, wetlands with very poorly drained soil, an open loop geothermal well, or a private on-site well may be reduced to 50 feet if:
1. (1) Pipe having an SDR of 26 or equivalent is used and is solvent cemented or watertight at all pipe joints; and
2. (2) The tank is monolithic and made from concrete, plastic, fiberglass, or other material meeting Env-Wq 1010 watertight tank requirements or the tank has a reinforced mid-seam seal that is watertight.
(c) The distance between a water main or pressurized water service line and a bed may be reduced to 5 feet, and the distance from a water main or pressurized water service line to a septic tank may be reduced to 5 feet, if the waterline is sleeved in a single, continuous length of SDR 35 pipe or equivalent, to the distance specified in Table 1008-2.
(d) For any well for which a wellhead protection area has been established pursuant to RSA 485-C, the distance between the well and the septic system components shall be as established in the applicable rule in Env-Dw 300.
(e) Setbacks to known burial sites, burial grounds, and cemeteries shall comply with RSA 289:3, III, which prohibits new construction, excavation, and building within 25 feet of a known burial site or within 25 feet of the boundaries of an established burial ground or cemetery, subject to local regulations.

Source. (See Revision Notes #1 and #2 at chapter heading for Env-Wq 1000) #11184, eff 10-1-16; ss by #14486, eff 2-1-26, EXPIRES: 2-1-36 (formerly Env-Wq 1008.04)