Wisconsin Administrative Code, Subchapter J, Section NR 665.0193 - Containment and detection of releases | Wisconsin Administrative Code

(1) In order to prevent the release of hazardous waste or hazardous constituents to the environment, secondary containment that meets the requirements of this section shall be provided (except as provided in subs. (6) and (7)):

(a) For all new and existing tank systems or components, prior to their being put into service.

(b) For tank systems that store or treat materials that become hazardous wastes, within 2 years of the hazardous waste listing, or when the tank system has reached 15 years of age, whichever comes later.

(2) Secondary containment systems shall be all of the following:

(a) Designed, installed and operated to prevent any migration of wastes or accumulated liquid out of the system to the soil, groundwater or surface water at any time during the use of the tank system.

(b) Capable of detecting and collecting releases and accumulated liquids until the collected material is removed.

(3) To meet the requirements of sub. (2), secondary containment systems shall be at a minimum all of the following:

(a) Constructed of or lined with materials that are compatible with the wastes to be placed in the tank system and shall have sufficient strength and thickness to prevent failure due to pressure gradients (including static head and external hydrological forces), physical contact with the waste to which they are exposed, climatic conditions, the stress of installation and the stress of daily operation (including stresses from nearby vehicular traffic).

(b) Placed on a foundation or base capable of providing support to the secondary containment system and resistance to pressure gradients above and below the system and capable of preventing failure due to settlement, compression or uplift.

(c) Provided with a leak detection system that is designed and operated so that it will detect the failure of either the primary and secondary containment structure or any release of hazardous waste or accumulated liquid in the secondary containment system within 24 hours, or at the earliest practicable time if the existing detection technology or site conditions will not allow detection of a release within 24 hours.

(d) Sloped or otherwise designed or operated to drain and remove liquids resulting from leaks, spills or precipitation. Spilled or leaked waste and accumulated precipitation shall be removed from the secondary containment system within 24 hours, or in as timely a manner as is possible to prevent harm to human health or the environment, if removal of the released waste or accumulated precipitation cannot be accomplished within 24 hours.

Note: If the collected material is a hazardous waste under ch. NR 661, it is subject to management as a hazardous waste according to all applicable requirements of chs. NR 662 to 664 and this chapter. If the collected material is discharged through a point source to waters of the state, it is subject to ss. 283.31 and 283.33, Stats. If discharged to a publicly owned treatment works (POTW), it is subject to s. 283.21(2), Stats. If the collected material is released to the environment, it may be subject to the reporting requirements of 40 CFR part 302 and the requirements of s. 292.11, Stats., and chs. NR 706 to 726.

(4) Secondary containment for tanks shall include one or more of the following devices:

(a) A liner (external to the tank).

(b) A vault.

(c) A double-walled tank.

(d) An equivalent device as approved by the department.

(5) In addition to the requirements of subs. (2) to (4), secondary containment systems shall satisfy the following requirements:

(a) External liner systems shall be all of the following:

1. Designed or operated to contain 100 percent of the capacity of the largest tank within its boundary.

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.

3. Free of cracks or gaps.

4. Designed and installed to completely surround the tank and to cover all surrounding earth likely to come into contact with the waste if released from the tank (i.e., capable of preventing lateral as well as vertical migration of the waste).

5. 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.

(b) Vault systems shall be all of the following:

1. Designed or operated to contain 100 percent of the capacity of the largest tank within its boundary.

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.

3. Constructed with chemical-resistant water stops in place at all joints (if any).

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.

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:

a. The definition of ignitable waste under s. NR 661.0021.

b. The definition of reactive waste under s. NR 661.0023 and may form an ignitable or explosive vapor.

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.

(c) Double-walled tanks shall be all of the following:

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.

2. Protected, if constructed of metal, from both corrosion of the primary tank interior and the external surface of the outer shell.

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.

Note: 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.

(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:

(a) Aboveground piping (exclusive of flanges, joints, valves and connections) that is visually inspected for leaks on a daily basis.

(b) Welded flanges, welded joints and welded connections that are visually inspected for leaks on a daily basis.

(c) Sealless or magnetic coupling pumps and sealless valves, that are visually inspected for leaks on a daily basis.

(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.

(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.

(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:

1. The nature and quantity of the waste.

2. The proposed alternate design and operation.

3. The hydrogeologic setting of the facility, including the thickness of soils between the tank system and groundwater.

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.

(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:

1. The potential adverse effects on groundwater, surface water and land quality taking into account all of the following:

a. The physical and chemical characteristics of the waste in the tank system, including its potential for migration.

b. The hydrogeological characteristics of the facility and surrounding land.

c. The potential for health risks caused by human exposure to waste constituents.

d. The potential for damage to wildlife, crops, vegetation and physical structures caused by exposure to waste constituents.

e. The persistence and permanence of the potential adverse effects.

2. The potential adverse effects of a release on groundwater quality, taking into account all of the following:

a. The quantity and quality of groundwater and the direction of groundwater flow.

b. The proximity and withdrawal rates of groundwater in the area.

c. The current and future uses of groundwater in the area.

d. The existing quality of groundwater, including other sources of contamination and their cumulative impact on the groundwater quality.

3. The potential adverse effects of a release on surface water quality, taking into account all of the following:

a. The quantity and quality of groundwater and the direction of groundwater flow.

b. The patterns of rainfall in the region.

c. The proximity of the tank system to surface waters.

d. The current and future uses of surface waters in the area and any water quality standards established for those surface waters.

e. The existing quality of surface water, including other sources of contamination and the cumulative impact on surface-water quality.

4. The potential adverse effects of a release on the land surrounding the tank system, taking into account all of the following:

a. The patterns of rainfall in the region.

b. The current and future uses of the surrounding land.

(c) The owner or operator of a tank system, for which a variance from secondary containment had been granted in accordance with the requirements of par. (a), at which a release of hazardous waste has occurred from the primary tank system but has not migrated beyond the zone of engineering control (as established in the variance), shall do all of the following:

1. Comply with the requirements of s. NR 665.0196, except sub. (4).

2. Decontaminate or remove contaminated soil to the extent necessary to do all of the following:

a. Enable the tank system, for which the variance was granted, to resume operation with the capability for the detection of and response to releases at least equivalent to the capability it had prior to the release.

b. Prevent the migration of hazardous waste or hazardous constituents to groundwater or surface water.

3. If contaminated soil cannot be removed or decontaminated in accordance with subd. 2., comply with the requirements of s. NR 665.0197(2).

(d) The owner or operator of a tank system, for which a variance from secondary containment had been granted in accordance with the requirements of par. (a), at which a release of hazardous waste has occurred from the primary tank system and has migrated beyond the zone of engineering control (as established in the variance), shall do all of the following:

1. Comply with the requirements of s. NR 665.0196(1) to (4).

2. Prevent the migration of hazardous waste or hazardous constituents to groundwater or surface water, if possible, and decontaminate or remove contaminated soil. If contaminated soil cannot be decontaminated or removed, or if groundwater has been contaminated, the owner or operator shall comply with the requirements of s. NR 665.0197(2).

3. If repairing, replacing or reinstalling the tank system, provide secondary containment in accordance with the requirements of subs. (1) to (6) or reapply for a variance from secondary containment and meet the requirements for new tank systems in s. NR 665.0192 if the tank system is replaced. The owner or operator shall comply with these requirements even if contaminated soil can be decontaminated or removed, and groundwater or surface water has not been contaminated.

(8) All of the following procedures shall be followed in order to request a variance from secondary containment:

(a) The department shall be notified in writing by the owner or operator that the owner or operator intends to conduct and submit a demonstration for a variance from secondary containment as allowed in sub. (7) according to the following schedule:

1. For existing tank systems, at least 24 months prior to the date that secondary containment must be provided in accordance with sub. (1).

2. For new tank systems, at least 30 days prior to entering into a contract for installation of the tank system.

(b) As part of the notification, the owner or operator shall also submit to the department a description of the steps necessary to conduct the demonstration and a timetable for completing each of the steps. The demonstration shall address each of the factors listed in sub. (7) (a) or (b).

(c) The demonstration for a variance shall be completed and submitted to the department within 180 days after notifying the department of intent to conduct the demonstration.

(d) The department will inform the public, through a newspaper notice, of the availability of the demonstration for a variance. The notice shall be placed in a daily or weekly major local newspaper of general circulation and shall provide at least 30 days from the date of the notice for the public to review and comment on the demonstration for a variance. The department also will hold a public hearing, in response to a request or at its own discretion, whenever such a hearing might clarify one or more issues concerning the demonstration for a variance. Public notice of the hearing will be given at least 30 days prior to the date of the hearing and may be given at the same time as notice of the opportunity for the public to review and comment on the demonstration. These 2 notices may be combined.

(e) The department will approve or disapprove the request for a variance within 90 days of receipt of the demonstration from the owner or operator and will notify in writing the owner or operator and each person who submitted written comments or requested notice of the variance decision. If the demonstration for a variance is incomplete or does not include sufficient information, the 90-day time period will begin when the department receives a complete demonstration, including all information necessary to make a final determination. If the public comment period in par. (d) is extended, the 90-day time period will be similarly extended.

(9) All tank systems, until the time that secondary containment meeting the requirements of this section is provided, shall comply with the following:

(a) For non-enterable underground tanks, a leak test that meets the requirements of s. NR 665.0191(2) (e) shall be conducted at least annually.

(b) For other than non-enterable underground tanks and for all ancillary equipment, the owner or operator shall either conduct a leak test as in par. (a) or develop a schedule and procedure for an assessment of the overall condition of the tank system by a qualified professional engineer. The schedule and procedure shall be adequate to detect obvious cracks, leaks and corrosion or erosion that may lead to cracks and leaks. The owner or operator shall remove the stored waste from the tank, if necessary, to allow the condition of all internal tank surfaces to be assessed. The frequency of these assessments shall be based on the material of construction of the tank and its ancillary equipment, the age of the system, the type of corrosion or erosion protection used, the rate of corrosion or erosion observed during the previous inspection and the characteristics of the waste being stored or treated.

Note: The practices described in the American Petroleum Institute (API) Publication Guide for Inspection of Refining Equipment, Chapter XIII, "Atmospheric and Low Pressure Storage Tanks", 4th edition, 1981, may be used, when applicable, as guidelines for assessing the overall condition of the tank system.

(c) The owner or operator shall maintain on file at the facility a record of the results of the assessments conducted in accordance with pars. (a) and (b).

(d) If a tank system or component is found to be leaking or unfit-for-use as a result of the leak test or assessment in pars. (a) and (b), the owner or operator shall comply with the requirements of s. NR 665.0196.