Section 18-9 - Mechanical Integrity Testing (MIT) of Class III Injection, Production, and Monitor Wells (a) A schedule and methods for Mechanical Integrity Testing shall be approved by the Administrator and included in the permit or Research and Development Testing License application (per Section 5(a)(v) of this Chapter) and shall constitute requirements of the permit. The schedule and methods shall meet the following requirements: - (i) The operator of a Class III injection or production well shall establish mechanical integrity as defined in Section 1 of this Chapter for each well prior to commencing injection.
- (ii) For demonstrating mechanical integrity as defined in Section 1 of this Chapter:
- (A) One of the following methods must be used to evaluate the absence of significant leaks in the casing, tubing, or packer:
- (I) Following an initial pressure test, monitoring of the tubing-casing annulus pressure with sufficient frequency to be representative, as determined by the Administrator, while maintaining an annulus pressure different from atmospheric pressure measured at the surface; or
- (II) Pressure test with liquid or gas.
- (B) One of the following methods must be used to determine the absence or significant fluid movement into any unauthorized zone or water-bearing strata through vertical channels adjacent to the injection bore:
- (I) The results of a temperature or noise log (e.g. cement bond log); or
- (II) Where the nature of the casing precludes the use of the logging technique prescribed above, sealing records demonstrating the presence of adequate sealing material to prevent such migration shall be provided; or
- (III) Where the Administrator elects to rely on sealing records to demonstrate the absence of significant fluid movement, the monitoring program prescribed in Section 14 of this Chapter shall be designed to verify the absence of significant fluid movement.
- (C) The Administrator may allow the operator to use a test to demonstrate mechanical integrity other than those listed in subsection (A) above, if the alternate testing method is approved by the EPA. To obtain approval, the Administrator with concurrence of the Director, shall submit a written request to the EPA, which shall set forth the proposed test and all technical data supporting its use.
- (iii) Maintenance of the mechanical integrity of each Class III well, which has not been plugged or converted as required by Section 10 of this Chapter, shall be demonstrated at least once every five years or on a schedule determined by the Administrator.
- (iv) Before resuming injection into any Class III well that has been damaged by surface or subsurface activity or that has undergone an activity that may jeopardize the mechanical integrity of the well, such as the use of downhole cutting and underreaming tools, the operator must demonstrate the mechanical integrity of that well.
- (v) If the Administrator determines that a Class III well lacks mechanical integrity, he or she shall give written notice of this determination to the operator of the well. Unless the Administrator requires immediate cessation, the operator shall cease injection into the well within 48 hours of receipt of the Administrator's determination. The Administrator may allow plugging of the well or require the operator to perform such additional construction, operation, monitoring, reporting, and corrective action as is necessary to prevent the movement of fluid into unauthorized zones or onto the surface caused by the lack of mechanical integrity. The operator may resume injection upon written notification from the Administrator that the operator has demonstrated mechanical integrity.
- (vi) Results of MIT testing shall be reported quarterly in an electronic format as prescribed by the Administrator in accordance with the requirements in Section 15 of this Chapter.
020-18 Wyo. Code R. § 18-9
Adopted, Eff. 11/13/2018.