020-4 Wyo. Code R. § 4-7
All facilities shall be closed in accordance with the standards described in this section, as well as the requirements of Chapter 1, Section 2(g).
(a) Post-closure land use: All sites shall be returned to the use specified in the permit, following closure of the facility.
(b) Length of post-closure period: The post-closure period for construction/demolition landfills shall extend for a period of not less than five (5) years after completion of closure activities. Following this initial minimum period, the post-closure period shall be automatically extended until such time when the director determines, upon petition by the operator accompanied by submission of relevant information, that the facility has been adequately stabilized in a manner protective of human health and the environment.
(c) Notice on deed: At closure, an instrument which clearly gives notice of the use of the property as a construction/demolition landfill shall be filed in the county where the facility is located. Wording of such an instrument shall indicate that the property has been used as a solid waste disposal facility. This shall be recorded prior to any property transaction resulting in another use for the property.
(d) Posted notification for public: If the facility is open to the public, the operator shall arrange for notice of closure to be published in an area newspaper as well as posted at all facility access points.
(e) Minimum period for maintenance of access restriction: The operator shall not remove the facility's fence, gates and any other restrictions until the site has been closed and revegetated, if post-closure land use requires establishment of vegetative cover. Post-closure maintenance activities will be required for a minimum of 5 years.
(f) Prevention of erosion or ponding problems: For closure to be satisfactory, the site shall be engineered to inhibit future problems with erosion or ponding of surface water over filled areas. This may be done by site grading and revegetation, emplacement of rip rap or other appropriate means.
(g) Minimum thickness of subsoil and topsoil for final cover: For closure, a compacted layer of subsoil, or a combination of materials as specified in the permit, at least two feet (2') thick shall be constructed over the refuse or any intermediate cover already in place. This compacted layer shall be covered with at least six inches (6") of topsoil and graded to prevent erosion or surface water ponding.
(h) Seeding specifications: Any portion of the site disturbed by solid waste disposal activities shall be reseeded consistent with the post-closure land use, in order to establish vegetation capable of minimizing wind and water erosion of the final cover. Vegetation shall be of a diverse mixture selected for compatibility with climatic conditions, require little maintenance and have root depths that will not exceed the depth of the final cover.
(i) Commencement of closure: Closure activities as specified in this section and in the approved facility closure plan shall commence at a time no later than nine months following the time the facility ceases to receive solid wastes. Closure shall be promptly completed within twelve (12) months following commencement of closure activities unless the department approves interim measures with delayed final closure for good cause upon application by the operator.
(j) Surveyed corners: If not accomplished previously, all site boundary corners shall be surveyed and marked with permanent survey caps upon facility closure.
(k) Surface water diversion: Surface water diversion structures at any site shall be maintained in operating condition throughout the closure/post-closure period.
(l) Maintenance of environmental monitoring systems: The operator shall maintain all environmental monitoring systems for the length of the closure/post-closure period.
(m) Maintenance of corrective action systems: The operator shall respond to any pollution problem reasonably related to the facility's activities. The system shall be maintained for the length of the closure/post-closure period.
(n) Compliance with other standards: Each facility subject to the requirements of Chapter 6, 7, and/or 8 shall close, and maintain during the post-closure period in compliance with the requirements of those chapters, if applicable.
020-4 Wyo. Code R. § 4-7