Section 18 AAC 72.100 - Private water systems(a) Unless the department has approved a lesser minimum separation distance, a person who installs, modifies, or operates a source of drinking water associated with a private water system must meet the following minimum separation distances to a potential source of contamination: (1) at least 100 horizontal feet, measured nearest edge to nearest edge, to a wastewater treatment works, sewer line, sewer line cleanout, manhole, lift station, septic tank, wastewater holding tank, soil absorption system, disposal system, disposal sewer, pit privy, sanitary landfill, or other potential source of contamination such as animal byproducts, manure or waste, agricultural waste, sewage solids disposal sites, or biosolids storage areas;(2) at least 25 horizontal feet, measured nearest edge to nearest edge, to a private sewer line, sewer service line, or sump contained within a building;(3) at least 25 horizontal feet, measured nearest edge to nearest edge, to a land surface discharge or subsurface disposal area associated with drinking water treatment waste; in this paragraph, "drinking water treatment waste" includes reject water from reverse osmosis units and backwash water from filters and water softeners; and(4) at least 25 horizontal feet, measured nearest edge to nearest edge, to a fuel storage tank or line; the minimum separation distance to a fuel storage tank or line does not apply to (A) a tank or line that contains propane or natural gas; or(B) an above-ground storage tank or drum that, in the aggregate, has a storage capacity equal to or less than 500 gallons of petroleum products.(b) Unless the department has approved a lesser separation distance, a person who installs, modifies, or operates a water holding tank associated with a private water system or a private water line must meet the following minimum separation distances to potential sources of contamination: (1) at least 10 horizontal feet, measured nearest edge to nearest edge, to a fuel storage tank or line; the minimum separation distance for a fuel storage tank or line does not apply to (A) a tank or line that contains propane or natural gas; or(B) an above-ground storage tank or drum that, in the aggregate, has a storage capacity of equal to or less than 500 gallons of petroleum products;(2) at least five horizontal feet, measured nearest edge to nearest edge, to a septic tank, treatment tank, holding tank, lift station, community sewer line, land surface discharge, or subsurface disposal area;(3) at least 12 horizontal inches, measured nearest edge to nearest edge, to a private sewer line;(4) at locations where a private water line must cross a private or community sewer line, (A) at least 12 vertical inches, measured nearest edge to nearest edge, with the private or community sewer line located below the private water line; and(B) at least nine feet, measured nearest edge to nearest edge, from the private water line joints to the private or community sewer line joints.(c) A person who drills, installs, modifies, or operates a well serving a private water system must use a method equivalent to well protection or source water protection contained in 18 AAC 80 or the publicly identified approved best management practice as protective of a public water systems.(d) A person who owns or is responsible for a well shall maintain it in accordance with 18 AAC 80.015(d) or decommission it in accordance with 18 AAC 80.015(e).Eff. 10/1/2023, Register 247, October 2023Separation distance requirements for drinking water systems were previously addressed in 18 AAC 72.020. Lesser separation distances for private water systems are addressed under 18 AAC 72.060, 18 AAC 72.540, 18 AAC 72.640, or as part of an approval for a wastewater system under 18 AAC 72.200 - 18 AAC 72.290. Separation distance requirements for public water systems are addressed in 18 AAC 80 and all waivers involving a public water system are reviewed under that chapter.
In addition to the requirements in this section, requirements of the Department of Natural Resources under 11 AAC 93 (water management) or the state plumbing code, as developed under AS 18.60.705, might apply.
Methods publicly identified by the department as approved best management practices for non-public water wells and well decommissioning are available at a department office or on the department's website.
Authority:AS 44.46.020
AS 46.03.020
AS 46.03.050
AS 46.03.100
AS 46.03.365
AS 46.03.710