020-7 Wyo. Code R. § 7-5
(a) Any bond or other form of financial assurance may be canceled by the surety only after ninety (90) days written notice to the director, and upon receipt of the director's written consent, which may be granted only when the requirements of the bond have been fulfilled.
(b) When the director determines that the violation has been remedied or the damage abated, the director shall release that portion of the bond or financial assurance instrument being held under W.S. 35-11-504(a). When the director determines that closure activities have been successfully completed at any regulated facility, the director shall release that portion of the bond or financial assurance being held to guarantee performance of activities specified in W.S. W.S. 35-11-504(a). The remaining portion of the bond or financial assurance shall be held for a period of not less than thirty (30) years after the date of facility closure, or so long thereafter as necessary to assure proper performance of any post-closure and corrective activities specified in W.S. W.S. W.S. 35-11-504(a) unless the post-closure period is terminated at an earlier date under Chapter 2, Section 7(b).
(c) Release of the owner or operator from the closure financial assurance requirements of this chapter: Within sixty (60) days after receiving certification from the owner or operator that closure has been accomplished in accordance with the closure plan and the provisions of these regulations, the director shall verify that proper closure has occurred. Unless the director has reason to believe that closure has not been in accordance with the closure plan, the director shall notify the owner or operator in writing that the owner or operator is no longer required to maintain financial assurance for closure of the particular facility. Such notice shall release the owner or operator only from the requirements for financial assurance for closure of the facility; it does not release the owner or operator from legal responsibility for meeting the closure or post-closure standards. If no written notice or termination of financial assurance requirements or failure to properly perform closure is received by the owner or operator within sixty (60) days after certifying proper closure, the owner or operator may petition the director for an immediate decision in which case the director shall respond within ten (10) days after receipt of such petition.
(d) Release of the owner or operator from the post-closure financial assurance requirements of this chapter: Within sixty (60) days of the director's determination under Chapter 2, Section 7(b), that the facility has been adequately stabilized, the director shall notify the owner or operator in writing that the owner or operator is no longer required to maintain financial assurance for the post-closure care of the regulated facility. Such notice shall release the owner or operator only from the requirements for financial assurance for post-closure care of the facility; it does not release the owner or operator from legal responsibility to take corrective action as necessary to protect public health or the environment from releases from the facility.
020-7 Wyo. Code R. § 7-5