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Currently, there are no estimated processing times for this application.

Purpose of the Application

Companies must assess the H2S (sour gas) release rate when a proposed project might encounter H2S. This assessment will help determine the project’s emergency planning zone.

We expect companies to keep the release-rate assessment (including all supporting documents and calculations) in case of emergency and for auditing. It must be provided to our staff upon request.

Process Checklist

Before Applying
Before submitting a well licence application, the company must assess the H2S potential of all formations that the well will encounter. For every formation capable of resource recovery, a potential release rate must be calculated and incorporated into the well’s assessed H2S release rate.

For category C, D, and E wells, companies must

  • review Directive 056: Energy Development Applications and Schedules, table 7.1; and
  • complete, as part of the well licence application, schedule 4.3, which sets out H2S release rate for the well. This information forms the basis for the applicant’s participant involvement program related to the project.

Submit an Application
Companies must submit their H2S release-rate presubmissions by email to @email.

Our detailed checklist document and section 7.11.15 (H2S Release Rate Assessments) of Directive 056 can be reviewed to ensure that presubmission applications are complete.

Things to Remember
The company may file an H2S release-rate assessment (as a presubmission) before submitting a well licence application. This process can help the applicant

  • obtain our feedback on methodology and H2S release-rate assessments; and
  • reduce the time it takes us to process a well licence application.

Review Process

  1. The release-rate file will be assigned to a subject matter expert for initial review. If information is missing (i.e., the application is not complete), we will close the application. Otherwise, we will proceed with geological and engineering reviews.
  2. The geological review will focus on identifying all potential hydrocarbon-bearing zones; the release rates of those zones must then be calculated and included in the assessment. Sour zones that have been discounted from the release-rate calculation based on geological controls (i.e., facies changes) will be reviewed in detail.
  3. The engineering review will focus on selecting appropriate representative H2S concentrations and absolute open flow rates for each potential hydrocarbon-bearing zone; the release rate is then calculated for each zone.
  4. The applicant may receive a request for additional test information, calculations, or supporting evidence.
  5. We may request additional information (through a supplemental information request) to complete our technical review.
  6. If we are satisfied with the release-rate assessment and believe it sufficiently addresses H2S potential at the proposed location, we will issue an AER operator’s memo. This memo is valid for one year or until more data become available that result in a higher release-rate estimate.
  7. This operator’s memo must be attached to the Directive 056 well licence application. The company is responsible for ensuring that the release-rate assessment is updated if new data become available. When an operator’s memo is attached to the application, we do not re-review the release-rate assessment at the time of application.