Wisconsin Administrative Code, Subchapter S, Section NR 664.0552 - Corrective action management units (CAMUs) | Wisconsin Administrative Code

(1) To implement remedies under s. NR 664.0101, ss. 291.37 and 291.97(1), Stats., or 42 USC 6928(h) or to implement remedies at a licensed facility that is not subject to s. NR 664.0101, the department may designate an area at the facility as a corrective action management unit under the requirements in this section. In this section, "corrective action management unit" or "CAMU" means an area within a facility that is used only for managing CAMU-eligible wastes for implementing corrective action or cleanup at the facility. A CAMU shall be located within the contiguous property under the control of the owner or operator where the wastes to be managed in the CAMU originated. One or more CAMUs may be designated at a facility.

(a) In this section, "CAMU-eligible waste" means all of the following:

1. All solid and hazardous wastes, and all media (including groundwater, surface water, soils and sediments) and debris, that are managed for implementing cleanup. As-generated wastes (either hazardous or non-hazardous) from ongoing industrial operations at a site are not CAMU-eligible wastes.

2. Wastes that would otherwise meet the description in subd. 1. are not CAMU-eligible wastes if any of the following apply:

a. The wastes are hazardous wastes found during cleanup in intact or substantially intact containers, tanks or other non-land-based units found above ground, unless the wastes are first placed in the tanks, containers or non-land-based units as part of cleanup, or the containers or tanks are excavated during the course of cleanup.

b. The department exercises the discretion in par. (b) to prohibit the wastes from management in a CAMU.

3. Notwithstanding subd. 1., where appropriate, as-generated non-hazardous waste may be placed in a CAMU, where the waste is being used to facilitate treatment or the performance of the CAMU.

(b) The department may prohibit, where appropriate, the placement of waste in a CAMU where the department has or receives information that the wastes have not been managed in compliance with applicable land disposal treatment standards of ch. NR 668, or applicable unit design requirements of this chapter or applicable unit design requirements of ch. NR 665, or that non-compliance with other applicable requirements of chs. NR 660 to 673 likely contributed to the release of the waste.

(c) Prohibition against placing liquids in CAMUs.

1. The placement of bulk or noncontainerized liquid hazardous waste or free liquids contained in hazardous waste, whether or not sorbents have been added, in any CAMU is prohibited except where placement of the wastes facilitates the remedy selected for the waste.

2. The requirements in s. NR 664.0314(3) for placement of containers holding free liquids in landfills apply to placement in a CAMU except where placement facilitates the remedy selected for the waste.

3. The placement of any liquid which is not a hazardous waste in a CAMU is prohibited unless the placement facilitates the remedy selected for the waste or a demonstration is made pursuant to s. NR 664.0314(5).

4. The absence or presence of free liquids in either a containerized or a bulk waste shall be determined in accordance with s. NR 664.0314(2). Sorbents used to treat free liquids in CAMUs shall meet the requirements of s. NR 664.0314(4).

(d) Placement of CAMU-eligible wastes into or within a CAMU does not constitute land disposal of hazardous wastes.

(e) Consolidation or placement of CAMU-eligible wastes into or within a CAMU does not constitute creation of a unit subject to minimum technology requirements.

(2)

(a) The department may designate a regulated unit (as defined in s. NR 664.0090(1) (b)) as a CAMU, or may incorporate a regulated unit into a CAMU, if all of the following apply:

1. The regulated unit is closed or closing, meaning it has begun the closure process under s. NR 664.0113 or 665.0113.

2. Inclusion of the regulated unit will enhance implementation of effective, protective and reliable remedial actions for the facility.

(b) The subchs. F, G and H requirements and the unit-specific requirements of this chapter or ch. NR 665 that applied to the regulated unit will continue to apply to that portion of the CAMU after incorporation into the CAMU.

(3) The department shall designate a CAMU that will be used for storage or treatment only in accordance with sub. (6). The department shall designate all other CAMUs in accordance with all of the following:

(a) The CAMU shall facilitate the implementation of reliable, effective, protective and cost-effective remedies.

(b) Waste management activities associated with the CAMU may not create unacceptable risks to humans or to the environment resulting from exposure to hazardous wastes or hazardous constituents.

(c) The CAMU shall include uncontaminated areas of the facility, only if including the areas for the purpose of managing CAMU-eligible waste is more protective than management of the wastes at contaminated areas of the facility.

(d) Areas within the CAMU, where wastes remain in place after closure of the CAMU, shall be managed and contained so as to minimize future releases, to the extent practicable.

(e) The CAMU shall expedite the timing of remedial activity implementation, when appropriate and practicable.

(f) The CAMU shall enable the use, when appropriate, of treatment technologies (including innovative technologies) to enhance the long-term effectiveness of remedial actions by reducing the toxicity, mobility or volume of wastes that will remain in place after closure of the CAMU.

(g) The CAMU shall, to the extent practicable, minimize the land area of the facility upon which wastes will remain in place after closure of the CAMU.

(4) The owner or operator shall provide sufficient information to enable the department to designate a CAMU in accordance with the criteria in this section. This shall include, unless not reasonably available, information on all of the following:

(a) The origin of the waste and how it was subsequently managed (including a description of the timing and circumstances surrounding the disposal or release).

(b) Whether the waste was listed or identified as hazardous at the time of disposal or release.

(c) Whether the disposal or release of the waste occurred before or after the land disposal requirements of ch. NR 668 were in effect for the waste listing or characteristic.

(5) The department shall specify, in the license or order, requirements for CAMUs to include all of the following:

(a) Areal configuration requirements. The areal configuration of the CAMU.

(b) Design, operation, treatment and closure requirements. Except as provided in sub. (7), requirements for CAMU-eligible waste management to include the specification of applicable design, operation, treatment and closure requirements.

(c) Minimum design requirements. Except as provided in sub. (6), CAMUs into which wastes are placed shall be designed in accordance with all of the following requirements:

1. Unless the department approves alternate requirements under subd. 2., CAMUs that consist of new, replacement or laterally expanded units shall include a composite liner and a leachate collection system that is designed and constructed to maintain less than a 30-cm depth of leachate over the liner. In this section, "composite liner" means a system consisting of 2 components; the upper component shall consist of a minimum 30-mil flexible membrane liner (FML), and the lower component shall consist of at least a 2-foot layer of compacted soil with a hydraulic conductivity of no more than 1x10 -7 cm/sec. FML components consisting of high density polyethylene (HDPE) shall be at least 60 mil thick. The FML component shall be installed in direct and uniform contact with the compacted soil component.

2. The department may approve alternate requirements if any of the following apply:

a. The department finds that alternate design and operating practices, together with location characteristics, will prevent the migration of any hazardous constituents into the groundwater or surface water at least as effectively as the liner and leachate collection systems in subd. 1.

b. The CAMU is to be established in an area with existing significant levels of contamination, and the department finds that an alternative design, including a design that does not include a liner, would prevent migration from the unit that would exceed long-term remedial goals.

(d) Minimum treatment requirements. Unless the wastes will be placed in a CAMU for storage or treatment only in accordance with sub. (6), CAMU-eligible wastes that, absent this section, would be subject to the treatment requirements of ch. NR 668, and that the department determines contain principal hazardous constituents shall be treated to the standards specified in subd. 3.

1. Principal hazardous constituents are those constituents that the department determines pose a risk to human health and the environment substantially higher than the cleanup levels or goals at the site.

a. In general, the department will designate as principal hazardous constituents all of the following:

1) Carcinogens that pose a potential direct risk from ingestion or inhalation at the site at or above 10 -3.

2) Non-carcinogens that pose a potential direct risk from ingestion or inhalation at the site an order of magnitude or greater over their reference dose.

b. The department will also designate constituents as principal hazardous constituents, where appropriate, when risks to human health and the environment posed by the potential migration of constituents in wastes to groundwater are substantially higher than cleanup levels or goals at the site; when making such a designation, the department may consider factors such as constituent concentrations, and fate and transport characteristics under site conditions.

c. The department may also designate other constituents as principal hazardous constituents that the department determines pose a risk to human health and the environment substantially higher than the cleanup levels or goals at the site.

2. In determining which constituents are "principal hazardous constituents", the department shall consider all constituents which, absent this section, would be subject to the treatment requirements in ch. NR 668.

3. Waste that the department determines contains principal hazardous constituents shall meet treatment standards determined in accordance with subd. 4. or 5.

4. The following treatment standards apply to wastes placed in CAMUs:

a. For non-metals, treatment shall achieve 90% reduction in total principal hazardous constituent concentrations, except as provided by subd. 4. c.

b. For metals, treatment shall achieve 90% reduction in principal hazardous constituent concentrations as measured in leachate from the treated waste or media (tested according to the TCLP) or 90% reduction in total constituent concentrations (when a metal removal treatment technology is used), except as provided by subd. 4. c.

c. When treatment of any principal hazardous constituent to a 90% reduction standard would result in a concentration less than 10 times the universal treatment standard for that constituent, treatment to achieve constituent concentrations less than 10 times the universal treatment standard is not required. Universal treatment standards are identified in s. NR 668.48, Table UTS.

d. For waste exhibiting the hazardous characteristic of ignitability, corrosivity or reactivity, the waste shall also be treated to eliminate these characteristics.

e. For debris, the debris shall be treated in accordance with s. NR 668.45, or by methods or to levels established under subd. 4. a. to d. or 5., whichever the department determines is appropriate.

f. For metal bearing wastes for which metals removal treatment is not used, the department may specify a leaching test other than the TCLP (method 1311 of EPA SW-846, incorporated by reference in s. NR 660.11) to measure treatment effectiveness, provided the department determines that an alternative leach testing protocol is appropriate for use, and that the alternative more accurately reflects conditions at the site that affect leaching.

5. The department may adjust the treatment level or method in subd. 4. to a higher or lower level, based on one or more of the following factors, as appropriate. The adjusted level or method shall be protective of human health and the environment:

a. The technical impracticability of treatment to the levels or by the methods in subd. 4.

b. The levels or methods in subd. 4. would result in concentrations of principal hazardous constituents (PHCs) that are significantly above or below cleanup standards applicable to the site (established either site-specifically, or promulgated under state or federal law).

c. The views of the affected local community on the treatment levels or methods in subd. 4. as applied at the site, and, for treatment levels, the treatment methods necessary to achieve these levels.

d. The short-term risks presented by the on-site treatment method necessary to achieve the levels or treatment methods in subd. 4.

e. The long-term protection offered by the engineering design of the CAMU and related engineering controls where any of the following apply:

1) The treatment standards in subd. 4. are substantially met and the principal hazardous constituents in the waste or residuals are of very low mobility.

2) Cost-effective treatment has been used and the CAMU meets the liner and leachate collection requirements for new land disposal units at s. NR 664.0301(3) and (4).

3) After review of appropriate treatment technologies, the department determines that cost-effective treatment is not reasonably available, and the CAMU meets the liner and leachate collection requirements for new land disposal units at s. NR 664.0301(3) and (4).

4) Cost-effective treatment has been used and the principal hazardous constituents in the treated wastes are of very low mobility.

5) After review of appropriate treatment technologies, the department determines that cost-effective treatment is not reasonably available, the principal hazardous constituents in the wastes are of very low mobility and either the CAMU meets or exceeds the liner standards for new, replacement or laterally expanded CAMUs in par. (c) 1. and 2. or the CAMU provides substantially equivalent or greater protection.

6. The treatment required by the treatment standards shall be completed prior to, or within a reasonable time after, placement in the CAMU.

7. For the purpose of determining whether wastes placed in CAMUs have met site-specific treatment standards, the department may, as appropriate, specify a subset of the principal hazardous constituents in the waste as analytical surrogates for determining whether treatment standards have been met for other principal hazardous constituents. This specification will be based on the degree of difficulty of treatment and analysis of constituents with similar treatment properties.

(e) Groundwater monitoring and corrective action requirements. Except as provided in sub. (6), requirements for groundwater monitoring and corrective action that are sufficient to do all of the following:

1. Continue to detect and to characterize the nature, extent, concentration, direction and movement of existing releases of hazardous constituents in groundwater from sources located within the CAMU.

2. Detect and subsequently characterize releases of hazardous constituents to groundwater that may occur from areas of the CAMU in which wastes will remain in place after closure of the CAMU.

3. Require notification to the department and corrective action as necessary to protect human health and the environment for releases to groundwater from the CAMU.

(f) Closure and long-term care requirements. Except as provided in sub. (6), all of the following closure and long-term care requirements:

1. Closure of corrective action management units shall do all of the following:

a. Minimize the need for further maintenance.

b. Control, minimize or eliminate, to the extent necessary to protect human health and the environment, for areas where wastes remain in place, post-closure escape of hazardous wastes, hazardous constituents, leachate, contaminated runoff or hazardous waste decomposition products to the ground, surface waters or the atmosphere.

2. Requirements for closure of CAMUs shall include the following, as appropriate and as deemed necessary by the department for a given CAMU:

a. Requirements for excavation, removal, treatment or containment of wastes.

b. Requirements for removal and decontamination of equipment, devices and structures used in CAMU-eligible waste management activities within the CAMU.

3. In establishing specific closure requirements for CAMUs under this subsection, the department shall consider all of the following factors:

a. CAMU characteristics.

b. Volume of wastes which remain in place after closure.

c. Potential for releases from the CAMU.

d. Physical and chemical characteristics of the waste.

e. Hydrogeological and other relevant environmental conditions at the facility which may influence the migration of any potential or actual releases.

f. Potential for exposure of humans and environmental receptors if releases were to occur from the CAMU.

4. Cap requirements:

a. At final closure of the CAMU, for areas in which wastes will remain after closure of the CAMU, with constituent concentrations at or above remedial levels or goals applicable to the site, the owner or operator shall cover the CAMU with a final cover designed and constructed to meet all of the following performance criteria, except as provided in subd. 4. b.:

1) Provide long-term minimization of migration of liquids through the closed unit.

2) Function with minimum maintenance.

3) Promote drainage and minimize erosion or abrasion of the cover.

4) Accommodate settling and subsidence so that the cover's integrity is maintained.

5) Have a permeability less than or equal to the permeability of any bottom liner system or natural subsoils present.

b. The department may determine that modifications to the cap requirements of subd. 4. a. are needed to facilitate treatment or the performance of the CAMU (e.g., to promote biodegradation).

5. Long-term care requirements as necessary to protect human health and the environment, to include, for areas where wastes will remain in place, monitoring and maintenance activities and the frequency with which the activities shall be performed to ensure the integrity of any cap, final cover or other containment system.

(6) In this section, "CAMUs that are used for storage or treatment only" means CAMUs in which wastes will not remain after closure. Those CAMUs shall be designated in accordance with all of the requirements of this section, except as follows.

(a) CAMUs that are used for storage or treatment only and that operate according to the time limits established in the staging pile rules at s. NR 664.0554(4) (a) 3., (8) and (9) are subject to the requirements for staging piles at s. NR 664.0554(4) (a) 1. and 2. and (b), (5), (6), (10) and (11) in lieu of the performance standards and requirements for CAMUs in subs. (3) and (5) (c) to (f).

(b) CAMUs that are used for storage or treatment only and that do not operate according to the time limits established in the staging pile rules at s. NR 664.0554(4) (a) 3., (8) and (9):

1. Shall operate in accordance with a time limit, established by the department, that is no longer than necessary to achieve a timely remedy selected for the waste.

2. Are subject to the requirements for staging piles at s. NR 664.0554(4) (a) 1. and 2. and (b), (5), (6), (10) and (11) in lieu of the performance standards and requirements for CAMUs in subs. (3) and (5) (d) and (f).

(7) CAMUs into which wastes are placed where all wastes have constituent levels at or below remedial levels or goals applicable to the site do not have to comply with the requirements for liners at sub. (5) (c) 1., caps at sub. (5) (f) 4., groundwater monitoring requirements at sub. (5) (e) or, for treatment or storage-only CAMUs, the design standards at sub. (6).

(8) The department shall provide public notice and a reasonable opportunity for public comment before designating a CAMU. The notice shall include the rationale for any proposed adjustments under sub. (5) (d) 5. to the treatment standards in sub. (5) (d) 4.

(9) Notwithstanding any other provision of this section, the department may impose additional requirements as necessary to protect human health and the environment.

(10) Incorporation of a CAMU into an existing license shall be approved by the department according to the procedures for department-initiated license modifications under s. NR 670.041, or according to the license modification procedures of s. NR 670.042.

(11) The designation of a CAMU does not change the department's existing authority to address clean-up levels, media-specific points of compliance to be applied to remediation at a facility or other remedy selection decisions.