Idaho Administrative Code › Title IDAPA 20 - Lands, Department of › Rule 20.07.02 - RULES GOVERNING CONSERVATION OF OIL AND NATURAL GAS IN THE STATE OF IDAHO › Subchapter D - WELL SITES AND DRILLING › Section 20.07.02.310 - GENERAL DRILLING RULES

Current through August 31, 2023
01.
General Design Requirements for Casing and Cementing
. Casing and cementing programs adopted for wells must be so planned as to protect any potential oil- or gas-bearing horizons penetrated during drilling from infiltration of injurious waters from other sources, and to prevent the migration of oil or gas from one horizon to another. Owners and operators shall follow the standards for casing and tubing in API SPEC 5CT and the standards for cementing in API SPEC 10A. (3-18-22)
02.
Wildcat and High-Pressure Conditions
. When drilling wildcat territory or in any field where high pressures are likely to exist, the owner or operator shall take all necessary precautions to keep the well under control at all times and shall use proper high-pressure fittings and equipment at the time the well is started. Under such conditions all strings of casings must be securely anchored. (3-18-22)
03.
High Temperature Conditions
. Due to high geothermal gradients in Idaho, the temperature of the return drilling mud shall be monitored daily during the drilling of the surface casing hole and all deeper holes. The owner or operator must use cements appropriate for the temperatures expected or encountered. (3-18-22)
04.
Conductor Pipe or Casing Requirements
. A minimum of forty (40) feet of conductor pipe shall be installed. If geologic conditions are such that forty (40) feet is not feasible, the owner or operator may request a variance from the Department. The annular space is to be cemented solid to the surface. A twenty-four (24) hour cure period for the grout must be allowed prior to drilling out the shoe unless sufficient additives, as determined by the Department, are used to obtain early strength. (3-18-22)
05.
Surface Casing Requirements
. (3-18-22)
a. The Department must be notified in writing seventy-two (72) hours in advance of planned spud activity for surface casing. The Department will post the spud activity notice on its website and send an electronic copy of the notice to the county where the well is located. (3-18-22)
b. Surface casing must be set at a minimum depth equal to ten percent (10%) of the proposed total depth of the well. In areas where pressures and formations are unknown, a minimum of two hundred (200) feet of surface casing shall be set. (3-18-22)
c. Surface casing shall provide for control of formation fluids, protection of fresh water, and for adequate anchorage of blow out prevention equipment. The casing must be seated through a sufficient series of low permeability, competent lithologic units such as claystone, siltstone, basalt, etc., to insure a solid anchor for blow out prevention equipment and to protect usable ground water from contamination. Additional surface casing may be required if the first string has not been cemented through a sufficient series of low permeability, competent lithologic units, or rapidly increasing thermal gradients or formation pressures are encountered. (3-18-22)
d. All surface casing shall be cemented solid to the surface by pump and plug, displacement, or other approved method. When surface samples are cured, additional drilling activities may commence. (3-18-22)
e. The Department must be notified in writing twenty-four (24) hours in advance of planned cementing activity for surface casing. The Department will witness and document all surface casing cementing activities. (3-18-22)