WAC 173-240-035
Restrictions -- Subsurface disposal systems. Domestic wastewater facilities using subsurface sewage treatment
and disposal, as defined in WAC 173-240-020(5), are prohibited
except under those extraordinary circumstances where no other
reasonable alternatives exist and: Providing that
(1) The facility is owned, operated, and maintained by a
public entity, except as noted in WAC 173-240-104; and
(2) Adequate facility construction oversight is provided by
the public entity; and
(3) The proposed project is consistent with local health and
land use rules; and
(4) Loading rates do not exceed 1,570 gallons per day per
acre of gross land area in medium sands or finer grained soils
and may not exceed 900 gallons per day per acre of gross land in
coarser grained soils or other soils where conditions do not
provide for adequate treatment. For the purposes of this section
gross land area is defined as the contiguous land area of a
proposed development that might include the centerline of
adjoining road or street right-of-ways.
[Statutory Authority: RCW 90.48.110. 00-15-021 (Order 00-09), §
173-240-035, filed 7/11/00, effective 8/11/00. Statutory
Authority: Chapters 43.21A and 90.48 RCW. 83-23-063 (Order DE
83-30), § 173-240-035, filed 11/16/83.]