Michigan Compiled Laws, Chapter 324. Natural Resources and Environmental Protection § 324.21312a

(a) A summary of corrective action activities and documentation of the basis for concluding that corrective actions have been completed.

(b) Closure verification sampling results. Groundwater samples shall be collected utilizing a low-flow technique for closure verification or other method approved by the department.

(c) The person submitting a closure report shall include a signed affidavit attesting to the fact that the information upon which the closure report is based is complete and true to the best of that person's knowledge. The closure report shall also include a signed affidavit from the consultant who prepared the closure report attesting to the fact that the corrective actions detailed in the closure report comply with all applicable requirements under the applicable RBCA standard and that the information upon which the closure report is based is true and accurate to the best of that consultant's knowledge. In addition, the consultant shall attach a certificate of insurance demonstrating that the consultant has obtained at least all of the insurance required under section 21325.  3

(d) A person submitting a closure report shall maintain all documents and data prepared, acquired, or relied upon in connection with the closure report for not less than 6 years after the date on which the closure report was submitted. All documents and data required to be maintained under this section shall be made available to the department upon request.