R 324.804 Construction and operation of injection wells.

Rule 804. (1) Injection of fluid into an injection well shall be through a combination of casing, tubing, cement, and packer placement that isolates the injection interval and prevents the movement of fluids into or between underground sources of drinking water, including through vertical channels adjacent to the well bore, which has mechanical integrity. Injection wells utilized for gas storage are not required to install tubing and/or a packer. In addition to cementing requirements in this rule, well casing shall be cemented pursuant to R 324.408, R 324.411, and R 324.413. The supervisor or authorized representative of the supervisor shall review cement details and any logs required for the applicant to demonstrate external mechanical integrity prior to authorization to inject. One of the following methods that demonstrates external mechanical integrity and prevention of fluid migration into or between underground sources of drinking water shall be used: (a) The results of a temperature log, or noise log, or cement bond log. (b) Cementing records demonstrating the presence of adequate cement to prevent a migration. (c) Other methods suggested by the permittee and approved by the supervisor or authorized representative of the supervisor. (2) A permittee of a well shall ensure that the injection of fluid into a well is through adequate tubing and packer. During injection operations, the permittee shall fill the tubing to casing annulus with a noncorrosive liquid. For Class II wells, the packer shall be set within 100 feet of the base of the injection casing or within 100 feet of the top perforation of the injection interval, unless otherwise approved by the supervisor. Injection wells utilized for gas storage are exempt from this subrule. (3) A permittee of a well shall ensure that surface access to all casing annuli is provided. (4) A permittee of a well shall ensure that an injection well is constructed and operated so that the injection of fluids is confined to injection interval or intervals approved by the supervisor or authorized representative of the supervisor. (5) In addition to R 324.408 surface casing requirements, surface casing must be set a minimum of 100 feet below the base of the glacial drift into competent bedrock or 100 feet below all underground sources of drinking water, whichever is deeper, for new Class II wells. To convert a previously drilled well into a Class II well, where existing surface casing is not 100 feet below underground source of drinking water, a demonstration of the combination of casing and cement must be made to show protection of all underground sources of drinking water. (6) The injection casing must have a minimum of 250 feet of cement immediately above the injection interval. If less than 250 feet of cement exists, remedial cementing must occur at a point as near to the existing cement top as possible, as determined by the supervisor or authorized representative of the supervisor. Injection wells utilized for gas storage are exempt from this subrule. (7) Class II wells must have injection casing in addition to the surface casing and any additional casing that may be required under R 324.410. (8) In addition to other provisions of these rules, the top of the injection interval shall be a minimum of 500 feet below the deepest underground source of drinking water for a new Class II well in an area of karst, unless a lesser separation is approved by the supervisor based on a demonstration of protection of underground sources of drinking water by the permittee. Within an area of karst, in addition to other requirements, all casings except the injection casing shall be circulated to surface with cement. If not possible to circulate cement to surface because of karst features or lost circulation zones, the casing annulus shall have cement from at least 100 feet to the surface. (9) Subrules R 324.804(1), (5), and (6) do not apply to Existing Class II wells or Rule Authorized wells since they are permitted, constructed or converted prior to the date of primacy.