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:

(a) Commercial water supplies.

(b) Irrigation water supplies.

(c) Water supplies for any other purpose.

(d) Dewatering, or similar purposes.

(2) Exploration drillers.

(a) Hole drilling for geologic or hydrologic information.

(b) Core drilling for geologic information.

(3) Water well pump installers. The installation of water well pumps for all purposes, except commercial water supplies.

(4) Equipment oilers. Assist the drillers and pump installers in the performance of the tasks described above.