A. Surface casing shall be set a minimum of fifty feet (50') below the deepest freshwater zone found within a one mile radius of the well site. However, a minimum of two hundred feet (200') of surface casing shall be set. Resistivity and porosity electric log shall be run on the surface hole before surface pipe is set, a copy of which will be filed with the corporation commission, the Oklahoma water resources board, and the city. Surface pipe shall have a centralizer on the shoe joint, a centralizer within fifty feet (50') of the shoe joint, and centralizers no more than two hundred feet (200') apart above the second centralizer. Such surface casing must be set as soon as the proper depth for the casing has been drilled. No drilling to production strata shall be done until after the casing operation is complete.
B. Surface pipe shall be cemented by attempting to circulate good cement to the surface by normal displacement practices with sufficient cement to completely fill all the annular space behind such casing, to the surface of the ground. If cement cannot be circulated to the surface, 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 service pipe until the top of the cement is tagged. The remaining uncemented annular space shall then be cemented until good cement is circulated to the surface. Cementing of this surface casing shall be performed as soon as the depth described in subsection A of this section is reached, and prior to drilling the well to deeper formations. A copy of the cement log shall be filed with the city.
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 paragraph, the city shall be notified thereof sufficiently in advance in order to allow a city representative to be present and observe such operations.
D. All casing, including surface protection and production strings, shall be either seamless steel or equivalent quality oil well casing. Each production string or casing must comply with the API standards as to internal pressure yield strength. Each joint and length of each particular casing string shall have unconditionally passed a complete cold water test prior to setting. (Ord. 1939 § 4, 2009)