Wash. Admin. Code § 296-127-01391
For the purpose of the Washington state public works law, chapter 39.12 RCW, the work of water well drillers, exploration drillers, water well pump installers, and equipment oilers includes, but is not limited to:
(1) Water well drillers. The drilling of wells for:
(2) Exploration drillers.
[Statutory Authority: Chapter 39.12 RCW, RCW 43.22.270 and 43.22.051. WSR 00-15-077, § 296-127-01391, filed 7/19/00, effective 7/19/00.]