|(a) General. (1) The development permit or registration, the site operating plan, any closure plan, the structures gas monitoring plan, the safety and evacuation plan, and all other documents and plans required by this subchapter shall become operational requirements and shall be considered a part of the operating record of the development or structure. A copy of these documents shall be maintained on site in an office at the permitted/registered development. (2) The owner, operator, or lessee shall retain the operating record for the life of the structure. (3) Any deviation from the development permit/registration and incorporated plans or other related documents associated with the development permit or registration without approval of the executive director is a violation of this subchapter. (4) The development permit or registration holder shall notify the executive director, and any local pollution agency with jurisdiction that has requested to be notified, of any incident involving the facility relative to the development permit or registration and provisions for the remediation of the incident. (b) Landfill gas control. All landfill gases shall be monitored in accordance with the structures gas monitoring plan prepared as set forth in §330.957 of this title (relating to Contents of the Development Permit and Workplan Application) and §330.959 of this title (relating to Contents of Registration Application for an Existing Structure Built Over a Closed Municipal Solid Waste Landfill Unit). (1) Landfill gas monitoring. (A) The owner or lessee of a new structure to be built or an existing structure built over a closed municipal solid waste (MSW) landfill unit shall provide equipment for monitoring on-site structures, including, but not limited to, buildings, subsurface vaults, utilities, or any other areas where potential gas buildup would be of concern. (B) Monitoring on-site structures may include, but is not limited to, periodic monitoring using either permanently installed monitoring probes or continuous monitoring systems. (C) Structures located on top of the waste area shall be monitored on a continuous basis, and monitoring equipment shall be designed to trigger an audible alarm if the volumetric concentration of methane in the sampled air is greater than 1% within the venting pipe or permeable layer, and/or inside the structure. When practical, structures should be monitored after they have been closed overnight or for the weekend to allow for an accurate assessment of gas accumulation. (D) Areas of the structure where gas may accumulate should be monitored and include, but are not limited to, areas in, under, beneath, and around basements, crawl spaces, floor seams or cracks, and subsurface utility connections. (E) Gas monitoring and control systems shall be modified as needed to reflect modifications to the structure. (2) Reporting. (A) All on-site structures shall be sampled for methane on a monthly basis. All monthly sampling results shall be placed in the operating record of the facility in accordance with §330.125(b)(3) of this title (relating to Recordkeeping Requirements) and be made available for inspection by the executive director, and any local pollution agency with jurisdiction that has requested to be notified, in accordance with §330.125(c) of this title. If methane gas levels exceeding the limits specified in paragraph (1) of this subsection are detected, the owner, operator, or lessee shall notify the executive director and take action in accordance with §330.371(c) of this title (relating to Landfill Gas Management). (B) Sampling for specified trace gases may be required by the executive director when there is a possibility of acute or chronic exposure due to carcinogenic or toxic compounds. (c) Air criteria. (1) The closed MSW landfill is subject to commission jurisdiction concerning burning and air pollution control. The owner shall ensure that the closed MSW landfill does not violate any applicable requirement of the approved state implementation plan. (2) Ventilation of the closed MSW landfill and any enclosed structures shall be provided in accordance with all appropriate commission rules. (d) Ponded water. The ponding of water over waste in the closed MSW landfill unit, regardless of its origin, shall be prevented. Ponded water that occurs on a closed MSW landfill unit shall be eliminated as quickly as possible and the area in which the ponding occurred shall be filled in and regraded within seven days of the occurrence. (e) Water pollution control. Surface drainage in and around the structure shall be controlled to minimize surface water running onto, into, and off the closed MSW landfill. (f) Groundwater monitoring. Groundwater monitoring may be required by the executive director and shall be conducted in accordance with the requirements of Subchapter J of this title (relating to Groundwater Monitoring and Corrective Action). (g) Conduits. All conduits intended for the transport or carrying of fluids over or within the closed MSW landfill shall be double-containment (split casings shall not be used). To the extent possible, all such utilities shall be in fill material placed over the upgraded final cover. (h) Recordkeeping requirements. (1) The owner or lessee shall promptly record and retain in the operating record the following information: (A) all results from gas monitoring and any remediation plans pertaining to explosive and other gases; (B) all unit design documentation for the placement of gas monitoring systems and leachate or gas condensate removal or disposal related to the closed MSW landfill unit; (C) copies of all correspondence and responses relating to the development permit; (D) all documents relating to the operation and maintenance of the building, facility, or monitoring systems as they relate to the development permit; and (E) any other document(s) as specified by the approved development permit or by the executive director. (2) The owner, operator, or lessee shall provide written notification to the executive director, and any local pollution agency with jurisdiction that has requested to be notified, for each occurrence that documents listed in subsection (h) of this section are placed into or added to the operating record. All information contained in the operating record shall be furnished upon request to the executive director and shall be made available at all reasonable times for inspection by the executive director or his representative.