The surface casing holes shall be drilled with air or fresh water using native mud or near location mud. Chemically inert substances such as bentonite, barite, or lost-circulation material may be added to the fluid system as long as testing of the fresh water filtrate from a solution of the added material remains inert and of a nonpolluting nature.
(Prior Code, § 113.061) (Ord. 1583, passed 1-8-2008)