A. 1. Surface casing shall be set a minimum of two hundred feet (200') below the deepest encounter of treatable water found in eight (8) sections adjacent to the section in which the well is located. Logs which identify the base of treatable water, shall be run in the surface hole before the surface pipe is set. A copy of such logs shall be filed with the oil and gas inspector, or
2. Surface casing may be set without the above required logging, provided the applicant can demonstrate to the satisfaction of the oil and gas inspector that the bottom of the surface casing will extend through or into at least two hundred feet (200') of continuous impermeable clay barrier below the base of treatable water, is properly cemented and cement bond logs run with the quality of the cement bond approved by the oil and gas inspector. Surface pipe shall have a centralizer on the shoe joint, and centralizers within fifty feet (50') of the shoe joint, and a centralizer no more than two hundred feet (200') apart above the second centralizer.
B. Surface pipe shall be cemented by attempting to circulate good cement to surface by normal displacement practices. If cement cannot be circulated to surface due to washed out hole or lost circulation, the existing cement shall not be overdisplaced and a plug shall be left in the bottom of the casing string to be drilled out once the surface is set. The remaining open hole behind the surface pipe shall be cemented by running a tubing string between the conductor string and the surface pipe until the top of the cement is tagged. The remaining uncemented annular space will then be cemented until good cement is circulated to surface. No further drilling shall be accomplished until the cement has set for at least twenty four (24) hours, or in the alternative, until samples of the cement have passed independent laboratory tests satisfactory to the oil and gas inspector.
C. Where an existing well is to be used as an injection or disposal site, the existing casing and cement shall be of such integrity and depth as to adequately and safely isolate freshwater producing zones from the seepage or bleeding of injection fluids or disposants. Where additional protective operations are undertaken to comply with this subsection, the oil and gas inspector shall be notified thereof sufficiently in advance in order for him to be present for such operations. (Ord. 528 §1, 1982)