Rock quarries, gravel pits, borrow pits, and spoil disposal areas.
Not covered by the Surface Mine Reclamation Act of 1971 (chapter
78.44 RCW).
*(1) Location of pits. Except as approved by the department, rock quarries and gravel pits opened after January 1, 1975 shall be located above the 100-year flood level.
*(2) Location of spoil disposal areas. Except as approved by the department, spoil disposal areas shall be located:
(a) Above the 100-year flood level.
(b) Where the final slope after disposal will be no steeper than 1 1/2:1.
(c) Where practical, on areas having low potential timber productivity.
(d) Where the risk of sediment delivery from soil erosion and/or mass soil movement is minimal.
(e) All spoils shall be placed to allow drainage without additional water ponding.
(f) All spoils shall be located outside of Type A and Type B Wetlands and their wetland management zones. Spoils shall not be located within the boundaries of forested wetlands without written approval of the department and unless a less environmentally damaging location is unavailable. No spoil area greater than 0.5 acre in size shall be allowed within wetlands. (See WAC
222-24-015.)
*(3) Pit drainage. During construction and use of rock quarries, gravel pits, or borrow pits, runoff water shall be either diverted onto a stable portion of the forest floor or be passed through one or more settling basins as approved by the department.
*(4) Rehabilitation required. All rock quarries, gravel pits, spoil disposal areas and borrow pits used after January 1, 1975 shall be reclaimed within 2 years from the time the rock or gravel source is either exhausted or abandoned.
*(5) Rehabilitation standards. Where rehabilitation is required:
(a) Remove all deleterious material that has potential for damaging the public resource, the soil productivity, or that would prevent reforestation of an otherwise plantable area.
(b) Grade slopes to less than the angle of repose unless otherwise approved.
(c) Reforest in accordance with chapter
222-34 WAC to the extent practical.
(d) Seed nonforested exposed erodible soils with grass, clover or other ground cover.
*(6) Major spoil disposal operations. Where a spoil disposal operation involves more than 1,000 cubic yards of spoils:
(a) The spoils shall be placed to provide drainage onto a stable portion of the forest floor without water ponding within the disposal area;
(b) The site shall be reforested in accordance with chapter
222-34 WAC to the extent practical; and
(c) If significant erosion of the spoils develops, the eroding areas shall be water barred and any unreforested areas shall be matted, mulched, or seeded with grass or ground cover.
[Statutory Authority: Chapter
34.05 RCW, RCW
76.09.040, [76.09.]050, [76.09.]370,
76.13.120(9). WSR 01-12-042, § 222-24-060, filed 5/30/01, effective 7/1/01. Statutory Authority: RCW
76.09.040,
76.09.050 and chapter
34.05 RCW. WSR 92-15-011, § 222-24-060, filed 7/2/92, effective 8/2/92. Statutory Authority: RCW
76.09.040. WSR 87-23-036 (Order 535), § 222-24-060, filed 11/16/87, effective 1/1/88; Order 263, § 222-24-060, filed 6/16/76.]