Section 246-250-320 - Disposal site design for land disposal(1) Disposal site design for near-surface disposal. (a) Site design features shall be directed toward long-term isolation and avoidance of the need for continuing active maintenance after site closure.(b) The disposal site design and operation shall be compatible with the disposal site closure and stabilization plan and lead to disposal site closure that provides reasonable assurance that the performance objectives will be met.(c) The disposal site shall be designed to complement and improve, where appropriate, the ability of the disposal site's natural characteristics to assure that the performance objectives will be met.(d) Covers shall be designed to minimize to the extent practicable water infiltration, to direct percolating or surface water away from the disposed waste, and to resist degradation by surface geologic processes and biotic activity.(e) Surface features shall direct surface water drainage away from disposal units at velocities and gradients which will not result in erosion that will require ongoing active maintenance in the future.(f) The disposal site shall be designed to minimize to the extent practicable the contact of water with waste during storage, the contact of standing water with waste during disposal, and the contact of percolating or standing water with wastes after disposal.Wash. Admin. Code § 246-250-320
Statutory Authority: RCW 43.70.040. 91-02-049 (Order 121), recodified as § 246-250-320, filed 12/27/90, effective 1/31/91. Statutory Authority: RCW 70.98.080. 87-01-031 (Order 2450), § 402-61-230, filed 12/11/86.