Section 330.457 - Closure Requirements for Municipal Solid Waste Landfill Units that Receive Waste on or after October 9, 1993(a) The owner or operator shall install a final cover system for the unit that is designed and constructed to minimize infiltration and erosion. The final cover system shall be composed of no less than two feet of soil and consist of a clay-rich soil cover layer overlain by an erosion layer as follows. (1) For municipal solid waste landfill (MSW) units with a synthetic bottom liner, a synthetic membrane that has a permeability less than or equal to the permeability of any bottom liner system overlain by a clay-rich soil cover layer consisting of a minimum of 18 inches of earthen material with a coefficient of permeability no greater than 1 x 10 -5 centimeters/second (cm/sec). The minimum thickness of the synthetic membrane shall be 20 mils, or 60 mils in the case of high-density polyethylene, in order to ensure proper seaming of the synthetic membrane.(2) For MSW landfill units with no synthetic bottom liner, the clay-rich soil cover layer shall consist of a minimum of 18 inches of earthen material with a coefficient of permeability less than or equal to the permeability of any constructed bottom liner or natural subsoil present. The coefficient of permeability of the infiltration layer shall in no case exceed 1 x 10-5 cm/sec, even though the coefficient of permeability of the constructed bottom liner or natural subsoil is greater than 1 x 10-5 cm/sec or no data exist for the value(s) of the coefficient of permeability of the constructed bottom liner or natural subsoil.(3) For all MSW landfill units, the erosion layer shall consist of a minimum of six inches of earthen material that is capable of sustaining native plant growth and shall be seeded or sodded immediately following the application of the final cover in order to minimize erosion.(b) The final cover placed over a dedicated Class 1 industrial solid waste cell must consist of a minimum of 18 inches of uncontaminated topsoil overlying four feet of compacted clay-rich soil material with a coefficient of permeability no greater than 1 x 10-7 cm/sec unless waste is to be placed on top of the Class 1 industrial solid wastes. If waste is to be placed above Class 1 industrial solid wastes, the Class 1 industrial solid waste must first be covered with a four-foot layer of compacted clay-rich soil. The final cover over the aerial fill must meet the requirements of this subchapter and must include a flexible membrane component.(c) Quality control testing documentation is as follows. The owner or operator shall test the 18 inches of compacted clay-rich soil cover for its coefficient of permeability at a frequency of no less than one test per surface acre of final cover. Permeability data shall be submitted to the executive director.(d) The executive director may approve an alternative final cover design that:(1) a cover achieves an equivalent reduction in infiltration as the clay-rich soil cover layer specified in subsection (a)(1) or (2) of this section; and(2) provides equivalent protection from wind and water erosion as the erosion layer specified in subsection (a)(3) of this section.(e) The owner or operator of all MSW landfill units or lateral expansions at a facility shall prepare a written closure plan that describes the steps necessary to close all MSW landfill units at any point during the active life of the unit. The closure plan, at a minimum, shall include the following information:(1) a description of the final cover design, methods, and procedures to be used to install the cover;(2) an estimate of the largest area of the MSW landfill unit or MSW facility ever requiring a final cover at any time during the active life of the unit or MSW facility;(3) an estimate of the maximum inventory of wastes ever on-site over the active life of the unit or MSW facility;(4) a schedule for completing all activities necessary to satisfy the closure criteria; and(5) a final contour map depicting the proposed final contours, establishing top slopes and side slopes, proposed surface drainage features, and protection of any 100-year floodplain.(f) Implementation of the closure plan is as follows. (1) The owner or operator shall place a copy of the closure plan in the operating record by the initial receipt of waste.(2) No later than 45 days prior to the initiation of closure activities for an MSW landfill unit, the owner or operator of the unit shall provide written notification to the executive director of the intent to close the unit and place this notice of intent in the operating record.(3) The owner or operator of all MSW landfill units at a facility shall begin closure activities for each unit no later than 30 days after the date on which the unit receives the known final receipt of wastes or, if the unit has remaining capacity and there is a reasonable likelihood that the unit will receive additional wastes, no later than one year after the most recent receipt of wastes. A request for an extension beyond the one-year deadline for the initiation of closure may be submitted to the executive director for review and approval and shall include all applicable documentation necessary to demonstrate that the unit has the capacity to receive additional waste and that the owner or operator has taken and will continue to take all steps necessary to prevent threats to human health and the environment from the MSW landfill unit.(4) The owner or operator of an MSW landfill unit shall complete closure activities for the unit in accordance with the approved closure plan within 180 days following the initiation of closure activities as specified in paragraph (3) of this subsection. A request for an extension for the completion of closure activities may be submitted to the executive director for review and approval and shall include all applicable documentation necessary to demonstrate that closure will, of necessity, take longer than 180 days and all steps have been taken and will continue to be taken to prevent threats to human health and the environment from the unclosed MSW landfill unit.(5) Following completion of all closure activities for the MSW landfill unit, the owner or operator shall comply with the post-closure care requirements specified in § 330.463(b) of this title (relating to Post-Closure Care Requirements). The owner or operator shall submit to the executive director by registered mail for review and approval a certification, signed by an independent licensed professional engineer, verifying that closure has been completed in accordance with the approved closure plan. The submittal to the executive director shall include all applicable documentation necessary for certification of closure. Once approved, this certification shall be placed in the operating record.(6) Following receipt of the required closure documents, as applicable, and an inspection report from the agency's regional office verifying proper closure of the MSW landfill unit according to the approved closure plan, the executive director may acknowledge the termination of operation and closure of the unit and deem it properly closed.(g) Within ten days after closure of all MSW landfill units, the owner and operator shall submit to the executive director by registered mail a certified copy of an "affidavit to the public" in accordance with the requirements of § 330.19 of this title (relating to Deed Recordation) and place a copy of the affidavit in the operating record. In addition, the owner or operator shall record a certified notation of the deed to the facility property, or on some other instrument that is normally examined during title search, that will in perpetuity notify any potential purchaser of the property that the land has been used as a landfill facility and use of the land is restricted according to the provisions specified in § 330.465 of this title (relating to Certification of Completion of Post-Closure Care). The owner or operator shall submit a certified copy of the modified deed to the executive director and place a copy of the modified deed in the operating record within the time frame specified in this subsection.30 Tex. Admin. Code § 330.457
The provisions of this §330.457 adopted to be effective March 27, 2006, 31 TexReg 2502