Current through Register Vol. 48, No. 11, November 22, 2024
Section 121-8.12 - Casing and CementingA. The operator of any oil or gas well shall case and cement all wells with a sufficient number of strings of casing in a manner necessary to: (1) Prevent release of fluids from any stratum through the well bore (directly or indirectly) into the ground waters, surface water, or onto the surface, except into pits or tanks provided for this purpose;(2) Prevent communication between separate hydrocarbon bearing strata (except where such strata have been approved for commingling) and between hydrocarbon and water-bearing strata;(3) Prevent contamination of freshwater strata;(4) Support unconsolidated sediments; and(5) Otherwise provide a means to control formation pressures and fluids.B. Suitable and sufficient surface casing shall be run and cemented to a depth not less than fifty feet below all USDW's encountered in the well. Sufficient cement shall be used to fill the annular space behind the surface casing from the base thereof to the surface of the ground. Cement shall be added from the bottom upward and circulated back to the surface. All cement shall be allowed to set 12 hours before the cement plug is drilled or tests initiated. During the 12 hour setting period, the cement shall be maintained in the annular space. If circulation is lost, a temperature or cement bond log shall be run to determine whether the casing is properly cemented. If the annular space is not properly cemented by the primary operation, the operator shall perform supplementary cementing operations to assure a seal across any gradational freshwater-saltwater contact or contacts as determined by subsurface control.C. All producing wells shall be completed with a production string of casing that shall be properly cemented at a sufficient depth to adequately protect the hydrocarbon-bearing stratum. Casing shall be cemented in place with a sufficient amount of cement to fill the calculated annular space to a point at least five hundred (500) feet above either the top of the producing interval or the top of the casing shoe, to be determined by the Commission. Cement shall be allowed to stand a minimum of twelve (12) hours before drilling the plug and tested at a pressure in pounds per square inch (psi), calculated by multiplying the length of the producing string by two-tenths ( 2/10) or any other pressure required by the Commission. The maximum test pressure required shall not exceed fifteen hundred (1,500) pounds per square inch. If, at the end of thirty (30) minutes, the pressure gauge shows a drop of ten percent (10%) of the test pressure or more, such corrective measures shall be taken as will ensure that the producing string of casing is so set and cemented that it will hold the pressure for thirty (30) minutes without a drop of more than ten percent (10%) of the test pressure on the gauge.S.C. Code Regs. § 121-8.12