NR 664.0301(1)(1) Any landfill that is not covered by sub. (3) or s. NR 665.0301 (1) shall have a liner system for all portions of the landfill (except for existing portions of the landfill). The liner system shall have both of the following:

NR 664.0301(1)(a)(a) A liner that is designed, constructed and installed to prevent any migration of wastes out of the landfill to the adjacent subsurface soil or groundwater or surface water at any time during the active life (including the closure period) of the landfill. The liner shall be constructed of materials that prevent wastes from passing into the liner during the active life of the facility. The liner shall be all of the following:

NR 664.0301(1)(a)1.1. Constructed of materials that have appropriate chemical properties and sufficient strength and thickness to prevent failure due to pressure gradients (including static head and external hydrogeologic forces), physical contact with the waste or leachate to which they are exposed, climatic conditions, the stress of installation and the stress of daily operation.

NR 664.0301(1)(a)2.2. Placed upon a foundation or base capable of providing support to the liner and resistance to pressure gradients above and below the liner to prevent failure of the liner due to settlement, compression or uplift.

NR 664.0301(1)(b)(b) A leachate collection and removal system immediately above the liner that is designed, constructed, maintained and operated to collect and remove leachate from the landfill. The department shall specify design and operating conditions in the operating license to ensure that the leachate depth over the liner does not exceed 30 cm (one foot). The leachate collection and removal system shall be both of the following:

NR 664.0301(1)(b)1.b.b. Of sufficient strength and thickness to prevent collapse under the pressures exerted by overlying wastes, waste cover materials and any equipment used at the landfill.

NR 664.0301(2)(2) The owner or operator will be exempted from the requirements of sub. (1) if the department finds, based on a demonstration by the owner or operator, that alternative design and operating practices, together with location characteristics, will prevent the migration of any hazardous constituents (see s. NR 664.0093) into the groundwater or surface water at any future time. In deciding whether to grant an exemption, the department will consider all of the following:

NR 664.0301(2)(a)(a) The nature and quantity of the wastes.

NR 664.0301(2)(b)(b) The proposed alternate design and operation.

NR 664.0301(2)(c)(c) The hydrogeologic setting of the facility, including the attenuative capacity and thickness of the liners and soils present between the landfill and groundwater or surface water.

NR 664.0301(2)(d)(d) All other factors which would influence the quality and mobility of the leachate produced and the potential for it to migrate to groundwater or surface water.

NR 664.0301(3)(3) The owner or operator of each new landfill unit on which construction commences after June 1, 1995, each lateral expansion of a landfill unit on which construction commences after June 1, 1995, and each replacement of an existing landfill unit that is to commence reuse after June 1, 1995 shall install 2 or more liners and a leachate collection and removal system above and between the liners. “Construction commences” is as defined in s. NR 660.10 under “existing facility”.

NR 664.0301(3)(a)(a)

NR 664.0301(3)(a)1.a.a. A top liner designed and constructed of materials (e.g., a geomembrane) to prevent the migration of hazardous constituents into the liner during the active life and long-term care period.

NR 664.0301(3)(a)1.b.b. A composite bottom liner, consisting of at least 2 components. The upper component shall be designed and constructed of materials (e.g., a geomembrane) to prevent the migration of hazardous constituents into this component during the active life and long-term care period. The lower component shall be designed and constructed of materials to minimize the migration of hazardous constituents if a breach in the upper component were to occur. The lower component shall be constructed of at least 3 feet (91 cm) of compacted soil material with a hydraulic conductivity of no more than 1×10-7 cm/sec.

NR 664.0301(3)(b)(b) The leachate collection and removal system immediately above the top liner shall be designed, constructed, operated and maintained to collect and remove leachate from the landfill during the active life and long-term care period. The department will specify design and operating conditions in the operating license to ensure that the leachate depth over the liner does not exceed 30 cm (one foot). The leachate collection and removal system shall comply with par. (c) 3. and 4.

NR 664.0301(3)(c)(c) The leachate collection and removal system between the liners, and immediately above the bottom composite liner in the case of multiple leachate collection and removal systems, is also a leak detection system. This leak detection system shall be capable of detecting, collecting and removing leaks of hazardous constituents at the earliest practicable time through all areas of the top liner likely to be exposed to waste or leachate during the active life and long-term care period. The requirements for a leak detection system in this subsection are satisfied by installation of a system that is, at a minimum, all of the following:

NR 664.0301(3)(c)2.2. Constructed of granular drainage materials with a hydraulic conductivity of 1×10-2 cm/sec or more and a thickness of 12 inches (30.5 cm) or more; or constructed of synthetic or geonet drainage materials with a transmissivity of 3×10-5 m2/sec or more.

NR 664.0301(3)(c)3.3. Constructed of materials that are chemically resistant to the waste managed in the landfill and the leachate expected to be generated, and of sufficient strength and thickness to prevent collapse under the pressures exerted by overlying wastes, waste cover materials and equipment used at the landfill.