Minimum Surface Casing Requirements--Appendix A

Definition of conductor pipe

A large diameter steel casing, having a minimum diameter of 12 inches, installed in an oil-and-gas-related well to protect fresh and usable water and stabilize unconsolidated materials when drilling in an area where the possibility of lost circulation zones exist at deeper depths.

Addition to minimum surface casing table

Within the sections listed below in this Appendix, the following rule shall be used for drilling any oil, gas, injection, disposal or service well: Conductor pipe shall be installed as soon as drilling penetrates twenty feet into the consolidated formation underlying the unconsolidated material. The annular space between the conductor pipe and the borehole shall be cemented from bottom to ground surface.

Conductor pipe, in addition to having a minimum diameter of 12 inches, shall be of sufficient size that if a lost circulation zone is encountered, the standard surface pipe can be installed through that zone. In areas where instability occurs within the unconsolidated materials, a pipe of sufficient diameter must be utilized to stabilize that portion of the borehole so that the minimum required amount of conductor pipe can be installed 20 feet into the underlying formation.

In those areas where the Appendix A list of sections includes sites that do not appear to have the unconsolidated material, a sufficient length of conductor pipe shall be on hand at the drilling site. In all cases, if unconsolidated material is encountered, conductor pipe shall be installed. If unconsolidated material is not encountered, the minimum required surface pipe shall be installed.

Section designated as having Wellington Aquifer with Hutchinson Salt Member present

Twp. 13S R. 3W Sec. 4, 5, 8-10, 15-17, 20-23, 25-29, 32-36

Twp. 14S R. 3W Sec. 1-5, 8-17, 20-29, 32-36

Twp. 15S R. 3W Sec. ALL

Twp. 15S R. 2W Sec. 6, 7, 18, 19, 30, 31

Twp. 16S R. 4W Sec. 1, 12, 13, 24, 25, 36

Twp. 16S R. 3W Sec. 4-9, 18, 19, 30, 31

Twp. 17S R. 4W Sec. 1, 12-14, 23-27, 34-36

Twp. 17S R. 3W Sec. 4-10, 16-20, 29-32

Twp. 18S R. 4W Sec. 1-4, 8-17, 20-29, 32-36

Twp. 18S R. 3W Sec. 6, 7 , 18, 19, 30, 31

Twp. 19S R. 4W Sec. 1-5, 8-17, 20-29, 32-36

Twp. 19S R. 3W Sec. 6, 7, 18, 19, 30, 31

Twp. 20S R. 4W Sec. 1-5, 9-16, 21-28, 33-36

Twp. 20S R. 3W Sec. 30, 31

Twp. 21S R. 4W Sec. 1-5, 8-17, 20-36

Twp. 21S R. 3W Sec. 6, 7, 18, 19, 30, 31

Twp. 22S R. 5W Sec. 1, 12, 13, 24, 25, 36

Twp. 22S R. 4W Sec. ALL

Twp. 22S R. 3W Sec. 6-8, 17-20, 28-33

Twp. 23S R. 5W Sec. 1, 11-14, 23-26-35, 36

Twp. 23S R. 4W Sec. ALL

Twp. 23S R. 3W Sec. 4-9, 16-21, 28-33

Twp. 24S R. 5W Sec. 1, 2, 12

Twp. 24S R. 4W Sec. 1-18, 20-27, 35, 36

Twp. 24S R. 3W Sec. ALL except 1, 2, 12

Twp. 24S R. 2W Sec. 19, 20, 27-35

Twp. 25S R. 4W Sec. 1

Twp. 25S R. 3W Sec. ALL except 18, 19, 29-33

Twp. 25S R. 2W Sec. ALL

Twp. 25S R. 1W Sec. 7, 17-21, 27-35

Twp. 26S R. 3W Sec. 1, 2, 12, 13

Twp. 26S R. 2W Sec. ALL except 1, 12, 11, 12

Twp. 26S R. 1W Sec. ALL

Twp. 26S R. 1E Sec. 18, 19, 29-32

Twp. 27S R. 2W Sec. 1-5, 8-17, 21-28, 33-36

Twp. 27S R. 1W Sec. ALL

Twp. 27S R. 1E Sec. 5-9, 16-21, 28-33

Twp. 28S R. 2W Sec. 1-3, 10-15, 22-27, 35, 36

Twp. 28S R. 1W Sec. ALL (36 No salt)

Twp. 28S R. 1E Sec. 4-10, 15-22, 26-35

Twp. 29S R. 2W Sec. 1, 2, 11-14, 23-26, 35, 36

Twp. 29S R. 1W Sec. ALL

Twp. 29S R. 1E Sec. ALL except 1

Twp. 30S R. 1W Sec. ALL except 18-20, 39-32

Twp. 30S R. 1E Sec. ALL

Twp. 30S R. 2E Sec. 6, 7, 17-21, 28-34

Twp. 31S R. 1W Sec. 1-3, 10-14, 23-26, 35, 36

Twp. 31S R. 1E Sec. ALL except 28, 29, 32, 33, 34

Twp. 31S R. 2E Sec. 3-11, 14-22, 28-31

Twp. 32S R. 1E Sec. 1

Twp. 32S R. 2E Sec. 5, 6

Twp. 33S R. 1E Sec. 31, 32

Twp. 34S R. 1E Sec. 1-3, 11-13

Twp. 34S R. 2E Sec. 6-8, 17-20