Cal. Code Regs. Tit. 27, div. 2, 1, ch. 7, subch. 1, art. 1, tbl. 1.3

Current through Register 2024 Notice Reg. No. 25, June 21, 2024

Table 1.3 - Natural and Artificial Containment Features for Mining Units

*Waste Group*	*Waste Management Unit*	*Geologic Setting*	*Liner(s) Hydr. Cond. Values (Units: cm/sec)*	*Leachate Collection and Removal System*
A	Waste Pile	per § 2531(b)(1) of Title 23, OR single clay liner¹ <1x10^-7			required
	Surface Impoundment or Tailings Pond	not applicable	double liner, both <1x10^-7 outer: clay; Inner: clay or synthetic		required⁽²⁾
B	Waste Pile	per § 20250(b)(1) OR single clay liner	<1x10^{-6 (1)}		required
	Surface Impoundment or Tailings Pond	not applicable	double liner, both <1x10^-6 // outer: clay or natural permeability⁽³⁾; inner: clay or synthetic OR single replaceable clay liner⁽⁴⁾		required⁽²⁾
C	Waste Pile, Surface Impoundment, or Tailings Pond	not applicable	not applicable		not applicable
(1) Synthetic liner may be used for short-term containment [see § 22490(f)(1)] .
(2) Liner and leachate collection and removal system for tailings pond must be able to withstand the ultimate weight of wastes.
(3) Permeability of <1x10^-6 cm/sec or natural geologic materials may replace outer liner of double liner system.
(4) Single clay liner <(1x10^-6 cm/sec) for surface impoundment, to be removed before last 25 percent (minimum 1 foot thickness) of liner is penetrated by fluid, including waste and leachate.