Technical Discussion of Permit Special Conditions
When an injection/disposal permit application is filed for a well that does not meet the Rule specified construction and operating standards, the well can often be permitted with additional permit special conditions. Some of the most common special permit conditions are:
- Wells that do not have surface casing set and cemented with SWR 13 quality cement throught the entire zone of usable quality groundwater will be permitted with a requirement to perform an annual Mechanical Integrity test (MIT) instead of the standard five-year test frequency. In addition, if any part of the groundwater is protected only by uncemented casing, then tubing-casing annulus monitoring will be required on a weekly basis.
- Wells that do not have sufficient production casing cement to ensure confinement of injected fluids will be required to perform a cement squeezeprior to beginning injection activity. The cement squeeze must be documented by a cementers affidavit (Form W-15) attached to the updated completion report (Form W-2). A copy of the W-15 should be attached to the initial pressure test report (Form H-5). Alternatively, a Cement Bond Log (CBL) may be submitted to see if the existing cement is adequate to confine injected fluids. If the CBL review verifies that the existing cement is adequate, then the "squeeze condition" will be satisfied.
- Wells that are being converted to injection in a shallower formation but have not yet been plugged back, will be required to perform the plug back with either a cement plug at the base of the permitted injection interval prior to beginning injection activity. The cement squeezes/plugs/bridge plugs must be documented by a cementers affidavit (Form W-15) attached to the updated completion report (Form W-2). A copy of the W-15 should be attached to the initial pressure test report (Form H-5)
- Wells that do not have sufficient geologic separation (250 feet of cumulative clay or shale) between the deepest groundwater and the permitted injection zone will be limited to re-injecting fluids from the same producing formation. Fluids from other formations may not be injected.
- Wells that are being converted to injection in a different formation but have not yet squeezed off existing open perforations, will be required to perform the cement squeeze of the perforations to beginning injection activity. The cement squeeze must be documented by a cementers affidavit (Form W-15) attached to the updated completion report (Form W-2).
- Wells that are being permitted for dual injection and production activity will typically have extensive additional monitoring requirements to allow for a five-year MIT schedule instead of the usual annual MIT. The MIT for a dual injection/production well is cumbersome due the the need to demonstrate mechanical integrity of the tubing, packer, and casing from ground surface to the injection zone. This testing requirement includes the casing between the injection and production zones, as well as of the injection string installation after the MIT.