1. (1) The area of review is the region surrounding the geologic sequestration project where USDWs may be endangered by the injection activity. The area of review is delineated using computational modeling that accounts for the physical and chemical properties of each phase of the injected carbon dioxide stream and is based on available site characterization, monitoring, and operational data.

2. (2) The operator of a Class VI well must prepare, maintain, and comply with a plan to delineate the area of review for the proposed geologic sequestration project, periodically reevaluate the delineation, and perform corrective action that meets the requirements of this section and is acceptable to the division. The requirement to maintain and implement an approved plan is directly enforceable regardless of whether the requirement is a condition of the permit. As a part of the permit application, the operator must submit an area of review and corrective action plan that includes the following information:

   1. (a) The method for delineating the area of review that meets the requirements of Subsection (3), including the model to be used, assumptions that will be made, and the site characterization data that the model will be based;

   2. (b) A description of:

      1. (i) The minimum fixed frequency, not to exceed five years, that the operator proposes to reevaluate the area of review;
      2. (ii) The monitoring and operational conditions that would warrant a reevaluation of the area of review prior to the next scheduled reevaluation as determined by the minimum fixed frequency established in Subsection (2)(b)(i).
      3. (iii) How monitoring and operational data, such as injection rate and pressure, will be used to inform an area of review reevaluation; and
      4. (iv) How corrective action will be conducted to meet the requirements of Subsection R644-8-3(1), including what corrective action will be performed prior to injection and what, if any, portions of the area of review the operator proposes to have corrective action addressed on a phased basis and how the phasing will be determined, how corrective action will be adjusted if there are changes in the area of review, and how site access will be guaranteed for future corrective action.

3. (3) An operator of a Class VI well must perform the following actions to delineate the area of review and identify each well that requires corrective action:

   1. (a) Predict, using existing site characterization, monitoring and operational data, and computational modeling, the projected lateral and vertical migration of the carbon dioxide plume and formation fluids in the subsurface from the commencement of injection activities until the plume movement ceases, until pressure differentials sufficient to cause the movement of injected fluids or formation fluids into a USDW are no longer present, or until the end of a fixed time period as determined by the division. The model must:

      1. (i) Be based on detailed geologic data collected to characterize each injection zone, confining zone and any additional zones; and anticipated operating data, including injection pressures, rates, and total volumes over the proposed life of the geologic sequestration project;
      2. (ii) Take into account any geologic heterogeneities, other discontinuities, and data quality, and their possible impact on model predictions; and
      3. (iii) Consider potential migration through faults, fractures, and artificial penetrations.
   2. (b) Using methods approved by the division, the operator shall at a minimum, identify each artificial penetration, including active wells, inactive wells, shut-in wells, abandoned wells and underground mines, in the area of review that penetrate each confining and injection zone. Provide a description of each well's type, construction, date drilled, location, depth, record of plugging, record of completion, and any additional information the division may require; and
   3. (c) Determine which abandoned wells in the area of review have, or have not, been plugged in a manner that prevents the movement of carbon dioxide or other fluids that may endanger USDWs, including the use of materials compatible with the carbon dioxide stream.

KEY: oil and gas law

Date of Last Change: July 31, 2025

Authorizing, and Implemented or Interpreted Law: 40-11-3