39-7415. STANDARDS FOR CLOSURE. (1) Applicability. These standards apply to all MSWLF units that receive wastes on or after October 9, 1993, except as provided by 40 CFR 258. MSWLF units that accept waste after October 9, 1991, but cease to accept waste prior to October 9, 1993, shall at a minimum comply with subsections (2)(a) and (3) of this section in addition to the "sanitary landfill closure guidance" criteria as adopted by the health district.

(2) Cover designs. Owners or operators of MSWLF units shall install one (1) of the following final cover systems:

(a) A cover as provided under 40 CFR 258.60(a); or

(b) The cover material must be fine-grained with intrinsic permeability no greater than 1 X 10-3 cm/sec and a minimum thickness of twenty-four (24) inches; and

(i) Have capillary holding capacity greater than the projected maximum accumulated volume of water as determined by utilization of accepted water balance methodology based on local or regional twenty-five (25) year climatic records;

(ii) Annual precipitation is less than twenty-five (25) inches with net evaporative losses greater than thirty (30) inches annually;

(iii) The top six (6) inches of the cover shall be capable of sustaining shallow rooted native plant growth; and

(iv) This design shall demonstrate consideration of site specific factors as provided in 40 CFR 258.60(b); or

(c) As provided in 40 CFR 258.60(b).

(3) The final grade of slopes shall be greater than two percent (2%) unless otherwise supported by the post closure plan and uses approved by the health district, and the grade of side slopes not more than thirty-three percent (33%).

(4) Closure plan preparation, placement in operating record, notice of intent to close, time requirements for commencement and completion of closure activities, certification, deed notation and removal of deed notation shall be conducted as provided in 40 CFR 258.60(c) through (j), inclusive. The deed notation and removal of deed notation shall comply with the uniform environmental covenants act, chapter 30, title 55, Idaho Code.

History:

[39-7415, added 1992, ch. 331, sec. 1, p. 988; am. 1993, ch. 139, sec. 16, p. 362; am. 1994, ch. 75, sec. 8, p. 169; am. 2010, ch. 99, sec. 2, p. 191.]