"Well" or "water well" as used in this chapter, means any
artificial excavation constructed by any method for the purpose of
extracting water from, or injecting water into, the underground. This
definition shall not include: (a) oil and gas wells, or geothermal
wells constructed under the jurisdiction of the Department of
Conservation, except those wells converted to use as water wells; or
(b) wells used for the purpose of (1) dewatering excavation during
construction, or (2) stabilizing hillsides or earth embankments.