SURFACE CASING

SURFACE CASING. The minimum amount of surface or first-intermediate casing to be set shall be determined from the following table: Proposed Total Minimum Casing Depth-Feet Requirements-Feet 0-2500 200’ 2500-6000 200’ + 8% of proposed depth in excess of 2500’ 6000-7000 480’ + 10% of proposed depth in excess of 6000’ 7000-8000 580’ + 15% of proposed depth in excess of 7000’ 8000-9000 730’ + 20% of proposed depth in excess of 8000’ 9000-Deeper 930’ + 25% of proposed depth in excess of 9000’ The proposed surface casing and cement program for each well shall be presented with the filing of Form No. 2, “Application to Drill”. The information shall include length of surface casing, anticipated grade, weight, connection and anticipated cementing program. Except for a dry hole completion where no production casing is set and the well is subsequently plugged, in all other instances, casing shall be cemented to the surface and pressure tested as provided below regardless of the mud disposal option. The proposed mud disposal program for each well shall be presented with the filing of Form No. 2, “Application to Drill”. In cases where drilling mud is to be disposed of down hole, the casing shall be set a minimum of 100 feet below the base of fresh water as determined using an induction resistivity log from the nearest well when possible or by other scientific methods approved by the Supervisor. The anticipated pressure authorized for any down hole disposal method of mud shall be presented in the mud disposal program and determined using the casing pressure test calculation as described below. At a minimum, casing shall be pressure tested subsequent to the hole being drilled for the production casing or the first-intermediate casing. Provided no testing pressure shall be less than 300 psig, the minimum pressure applied shall be determined using the following calculation: 0.22 psi/ft. x true vertical depth of casing shoe. The well shall have passed the test if there is a pressure loss of no greater than five per cent (5%) for a duration of one-half (1/2) hour as determined using a pen recording device. Any leaks in excess of five per cent (5%) pressure loss over one-half (1/2) hour shall be considered a significant leak and require remedial action in order to pass the pressure test. All casing pressure tests charts will be reviewed by the field inspector or his designee immediately following the test and subsequently forwarded to agency for processing. Exceptions to the above minimum requirements upon may be granted by the Board after notice and hearing and upon submission of proper evidence along with a statement on affidavit affirming all fresh water bearing zones will be adequately protected. In case an operator decides to drill deeper after drilling to his initial proposed total depth, he may secure relief to the above minimum casing requirements just as though his original intent was to drill the well as an exception to the minimum casing requirements, provided, however, that such exception is approved by the Supervisor.