The closure material must meet ASTM D-781 standard or equal and be installed as follows:
Wash. Admin. Code § 296-150C-1070
Statutory Authority: RCW 43.22.340, 43.22.350, 43.22.355, 43.22.360, 43.22.400, 43.22.432, 43.22.433, 43.22.434, 43.22.450, 43.22.480, and 43.22.485. 00-17-148, § 296-150C-1070, filed 8/22/00, effective 9/30/00. Statutory Authority: RCW 43.22.340,[43.22.]355 , [43.22.]360, [43.22.]432, [43.22.]440 and[43.22.]480 . 96-21-146, § 296-150C-1070, filed 10/23/96, effective 11/25/96.