US lawWashingtonRegulationsTitle 173 — ECOLOGY, DEPARTMENT OFChapter 173-100 — GROUNDWATER MANAGEMENT AREAS AND PROGRAMS173-100-020WAC 173-100-020WAC 173-100-020. AuthorityLast amended: 1986Year: 2026Length: 22 wordsOfficial source This chapter is promulgated by the department of ecology pursuant to RCW 90.44.400 , 90.44.410 , 90.44.420 , 90.44.430 and 90.44.440 .PreviousWAC 173-100-010NextWAC 173-100-030