(a) The owner or operator of a Class VI well must prepare, maintain, and comply with a testing and monitoring plan to verify that the geologic sequestration project is operating as permitted and is not endangering USDWs. - (i) The requirement to maintain and implement an approved plan is directly enforceable regardless of whether the requirement is a condition of the permit.
- (ii) The testing and monitoring plan must be submitted with the permit application, for administrator approval, and must include a description of how the owner or operator will meet the requirements of this section, including accessing sites for all necessary monitoring and testing during the life of the project.
(b) Testing and monitoring associated with geologic sequestration projects must, at a minimum, include: - (i) Plans and procedures for environmental surveillance and excursion detection, prevention and control programs, including a monitoring plan to:
- (A) Assess the migration of the injected carbon dioxide; and
- (B) Insure the retention of the carbon dioxide in the geologic sequestration site.
- (C) For purposes of this section, "excursion" shall mean the detection of migrating carbon dioxide at or beyond the boundary of the geologic sequestration site as defined in W.S. 35-11-103(c).
- (ii) Analysis of the carbon dioxide stream with sufficient frequency to yield data representative of its chemical and physical characteristics;
- (iii) Installation and use, except during well workovers, of continuous recording devices to monitor:
- (C) Pressure on the annulus between the tubing and the long string casing; and
- (D) The annulus fluid volume added.
- (E) The pressure on the annulus between the tubing and the long string casing.
- (iv) Corrosion monitoring of the well materials for loss of mass, thickness, cracking, pitting and other signs of corrosion must be performed and recorded at least quarterly to ensure that the well components meet the minimum standards for material strength and performance set forth in Section 9(b) by:
- (A) Analyzing coupons of the well construction materials placed in contact with the carbon dioxide stream; or
- (B) Routing the carbon dioxide stream through a loop constructed with the material used in the well and inspecting the materials in the loop; or
- (C) Using an alternative method, materials, or time period approved by the administrator.
- (v) Periodic monitoring of the reservoir fluid quality in a permeable and porous formation as near as practicable to the confining zone(s) for geochemical changes that may be a result of carbon dioxide or displaced formation fluid movement:
- (A) The location and number of monitoring wells must be based on specific information about the geologic sequestration project, including injection rate and volume, geology, the presence of artificial penetrations and other relevant factors; and
- (B) The monitoring frequency and spatial distribution of monitoring wells based on baseline geochemical data that have been collected under Section 5(b)(xi) and any modeling results in the area of review evaluation required by Section 8(c).
- (vi) A demonstration of external mechanical integrity pursuant to Section 13(c) at least once per year until the well is plugged; and if required by the administrator, a casing inspection log pursuant to requirements of Section 13(d) of this chapter at a frequency established in the testing and monitoring plan;
- (vii) A pressure fall-off test or other equivalent test that identifies reservoir conditions with respect to flow dynamics at least once every five years unless more frequent testing is required by the administrator based on site specific information; and
- (viii) Testing and monitoring to track the extent of the carbon dioxide plume, the position of the pressure front, and surface displacement by using:
- (A) Direct methods in the injection zone(s); and
- (B) Indirect methods (e.g., seismic, electrical, gravity, or electromagnetic surveys and/or down-hole carbon dioxide detection tools), unless the administrator determines, based on site-specific geology, that such methods are not appropriate;
- (ix) At the administrator's discretion, based on site-specific conditions, surface air monitoring and/or soil gas monitoring to detect movement of carbon dioxide that could endanger a USDW, or otherwise threaten human health, safety, or the environment.
- (A) The testing and monitoring plan must be based on potential risks to USDWs, and modeling within the area of review;
- (B) The monitoring frequency and spatial distribution of surface air monitoring and/or soil gas monitoring must reflect baseline data. The monitoring plan must specify how the proposed monitoring will yield useful information on the area of review delineation and the potential movement of fluid containing any contaminant into USDWs in exceedence of any primary drinking water regulation under 40 CFR Part 141, or which may otherwise adversely affect human health, safety, or the environment.
- (x) If an owner or operator demonstrates that monitoring employed under 40 CFR §§ 98.440 to 98.449 (Clean Air Act, 42 U.S.C. 7401 et seq.) accomplishes the goals of (h)(1) and (2) of this section, and meets the requirements pursuant to § 146.91(c)(5), a Director that requires surface air/soil gas monitoring must approve the use of monitoring employed under 40 CFR §§ 98.440 to 98.449. Compliance with §§ 98.440 to 98.449 pursuant to this provision is considered a condition of the Class VI permit;
- (xi) Any additional monitoring, as required by the administrator, necessary to support, upgrade, and improve computational modeling of the area of review re-evaluation required under Section 8(e) and as necessary to demonstrate that there is no movement of fluid containing any contaminant into underground sources of drinking water in exceedence of any primary drinking water regulation under 40 CFR Part 141, or which could otherwise adversely affect human health, safety, or the environment;
- (xii) The owner or operator shall periodically review the testing and monitoring plan to incorporate monitoring data collected under this subpart, operational data collected under Section 11 of this chapter, and the most recent area of review reevaluation performed under Section 8 of this chapter. In no case shall the owner or operator review the testing and monitoring plan less often than once every five years. Based on this review, the owner or operator shall submit an amended testing and monitoring plan or demonstrate to the administrator that no amendment to the testing and monitoring plan is needed. Any amendments to the testing and monitoring plan must be approved by the administrator, must be incorporated into the permit, and are subject to the permit modification requirements of Section 4 of this chapter, as appropriate. Amended plans or demonstrations shall be submitted to the administrator as follows:
- (A) Within one year of an area of review reevaluation;
- (B) Following any significant changes to the facility, such as addition of monitoring wells or newly permitted injection wells within the area of review, on a schedule determined by the administrator; or
- (C) When required by the administrator.
- (xiii) A quality assurance and surveillance plan for all testing and monitoring requirements.
020-24 Wyo. Code R. § 24-14