California Code, Public Resources Code - PRC § 41770

(a) Each countywide or regional agency integrated waste management plan, and the elements thereof, shall be reviewed, revised, if necessary, and submitted to the board every five years in accordance with the schedule set forth under Chapter 7 (commencing with Section 41800).

(b) Any revisions to a countywide or regional agency integrated waste management plan, and the elements thereof, shall use a waste disposal characterization method that the board shall develop for the use of the city, county, city and county, or regional agency. The city, county, city and county, or regional agency shall conduct waste disposal characterization studies, as prescribed by the board, if it fails to meet the diversion requirements of Section 41780, at the time of the five-year revision of the source reduction and recycling element.

(c) The board may review and revise its regulations governing the contents of revised source reduction and recycling elements to reduce duplications in one or more components of these revised elements.