(A) Surface casing shall be set a minimum of 200 feet below the deepest fresh water zone found in the well site section or in the eight sections adjacent to the wellsite section. If a well has previously been drilled in the same quarter section as the proposed well but does not have a previously run resistivity or porosity log to identify the base of the treatable water, or the proposed well is the first well in that quarter section, a resistivity and porosity log to identify the base of the treatable water, or other evidence satisfactory to the City Manager or his or her designee, shall be run in the surface, hole before surface pipe is set, a copy of which will be filed with the Corporation Commission, State Water Resources Board and the City Manager or his or her designee. Surface pipe shall have a centralizer on the shoe joint, a centralizer within 50 feet of the shoe joint and centralizers no more than 200 feet apart above the second centralizer.
(B) (1) Surface pipe shall be cemented by circulating 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 over-displaced 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.
(2) The City Manager or his or her designee may require logs to be run to determine the actual top of the cement in the annulus prior to pumping cement down the small string of pipe installed in the annulus of the well. The casing shall not be disturbed in any way until the cement has set for a minimum of eight hours or any longer time required for the cement to reach a compressive strength of 500 psi. A cement bond long shall be run after the cement has set for 12 hours and before drilling operations are resumed. The City Manager or his or her designee shall witness calibration and running of the cement bond log, and he or she shall examine the log and give his or her approval of the cement bond before drilling operations are resumed. Surface casing must be new pipe of API grade J or K or higher grade and have a minimum burst pressure rating of 2,900 psi.
(3) The City Manager or his or her designee may require cement samples as necessary to be submitted at drilling sites or elsewhere for quality control testing.
(C) (1) Where an existing well is to be used as an injection or disposal site, the existing casing and cement shall be of an integrity and depth as to adequately and safely isolate fresh water producing zones from the seepage or bleeding of injection fluids or disposants.
(2) Where additional protective operations are undertaken to comply with this division, the City Manager or his or her designee shall be notified thereof sufficiently in advance in order for him or her to be present for the operations.
(Ord. 2991, passed 7-19-94)