Solid waste composition study. The Department of Environmental Quality shall conduct a solid waste composition study to determine the quantities and sources of different materials disposed of in the waste stream at least once every three biennia for all areas of the state not covered by other solid waste composition studies. The study may include

(1) Measurement and composition of wastes disposed of through nonstandard methods such as litter; and

(2) The composition of commingled and other recovered materials collected or processed in Oregon. [1991 c.385 §5; 1993 c.560 §79; 2015 c.534 §11]