California Code, Public Resources Code - PRC § 43000

(a) “Waste management unit” means the area of a solid waste landfill facility in or on which solid wastes are placed for disposal.

(b) “New waste management unit” means a waste management unit which is not authorized on or before January 1, 1990, under waste discharge provisions adopted on or before that date pursuant to Division 7 (commencing with Section 13000) of the Water Code and for which a solid waste facility permit was not issued on or before that date pursuant to Title 7.3 (commencing with Section 66700) of the Government Code as it read before January 1, 1990.