NR 665.0193(5)(b)2.2. Designed or operated to prevent run-on or infiltration of precipitation into the secondary containment system unless the collection system has sufficient excess capacity to contain run-on or infiltration. The additional capacity shall be sufficient to contain precipitation from a 25-year, 24-hour rainfall event. NR 665.0193(5)(b)3.3. Constructed with chemical-resistant water stops in place at all joints (if any). NR 665.0193(5)(b)4.4. Provided with an impermeable interior coating or lining that is compatible with the stored waste and that will prevent migration of waste into the concrete. NR 665.0193(5)(b)5.5. Provided with a means to protect against the formation of and ignition of vapors within the vault, if the waste being stored or treated meets any of the following: NR 665.0193(5)(b)6.6. Provided with an exterior moisture barrier or be otherwise designed or operated to prevent migration of moisture into the vault if the vault is subject to hydraulic pressure. NR 665.0193(5)(c)1.1. Designed as an integral structure (i.e., an inner tank within an outer shell) so that the outer shell contains any release from the inner tank. NR 665.0193(5)(c)2.2. Protected, if constructed of metal, from both corrosion of the primary tank interior and the external surface of the outer shell. NR 665.0193(5)(c)3.3. Provided with a built-in, continuous leak detection system capable of detecting a release within 24 hours or at the earliest practicable time, if the owner or operator can demonstrate to the department, and the department concurs, that the existing leak detection technology or site conditions will not allow detection of a release within 24 hours. NR 665.0193 NoteNote: The provisions outlined in the Steel Tank Institute’s (STI) “Standard for Dual Wall Underground Steel Storage Tank” may be used as guidelines for aspects of the design of underground steel double-walled tanks.
NR 665.0193(6)(6) Ancillary equipment shall be provided with full secondary containment (e.g., trench, jacketing, double-walled piping) that meets the requirements of subs. (2) and (3) except for all of the following: NR 665.0193(6)(a)(a) Aboveground piping (exclusive of flanges, joints, valves and connections) that is visually inspected for leaks on a daily basis. NR 665.0193(6)(b)(b) Welded flanges, welded joints and welded connections that are visually inspected for leaks on a daily basis. NR 665.0193(6)(c)(c) Sealless or magnetic coupling pumps and sealless valves, that are visually inspected for leaks on a daily basis. NR 665.0193(6)(d)(d) Pressurized aboveground piping systems with automatic shut-off devices (e.g., excess flow check valves, flow metering shutdown devices, loss of pressure actuated shut-off devices) that are visually inspected for leaks on a daily basis. NR 665.0193(7)(7) The owner or operator may obtain a variance from the requirements of this section if the department finds, as a result of a demonstration by the owner or operator that alternative design and operating practices, together with location characteristics, will prevent the migration of hazardous waste or hazardous constituents into the groundwater or surface water at least as effectively as secondary containment during the active life of the tank system; or, that in the event of a release that does migrate to groundwater or surface water, no substantial present or potential hazard will be posed to human health or the environment. New underground tank systems may not, per a demonstration in accordance with par. (b), be exempted from the secondary containment requirements of this section. Application for a variance as allowed in this subsection does not waive compliance with the requirements of this subchapter for new tank systems. NR 665.0193(7)(a)(a) In deciding whether to grant a variance based on a demonstration of equivalent protection of groundwater and surface water, the department will consider all of the following: NR 665.0193(7)(a)3.3. The hydrogeologic setting of the facility, including the thickness of soils between the tank system and groundwater. NR 665.0193(7)(a)4.4. All other factors that would influence the quality and mobility of the hazardous constituents and the potential for them to migrate to groundwater or surface water. NR 665.0193(7)(b)(b) In deciding whether to grant a variance, based on a demonstration of no substantial present or potential hazard, the department will consider all of the following: NR 665.0193(7)(b)1.1. The potential adverse effects on groundwater, surface water and land quality taking into account all of the following: NR 665.0193(7)(b)1.a.a. The physical and chemical characteristics of the waste in the tank system, including its potential for migration. NR 665.0193(7)(b)1.d.d. The potential for damage to wildlife, crops, vegetation and physical structures caused by exposure to waste constituents.