Wis. Admin. Code Department of Natural Resources NR 722.07

Current through October 28, 2024
Section NR 722.07 - Identification and evaluation of remedial action options
(1) GENERAL. Unless otherwise directed by the department, responsible parties shall identify and evaluate an appropriate range of remedial action options in accordance with the requirements of this section.
(2)IDENTIFICATION OF LIKELY REMEDIAL ACTION OPTIONS. An initial screening of remedial technologies shall be conducted to identify remedial action options for further evaluation which are reasonably likely to be feasible for a site or facility, based on the hazardous substances present, media contaminated and site characteristics, and to comply with the requirements of s. NR 722.09.
(3)EVALUATION OF REMEDIAL ACTION OPTIONS.
(a) Except as provided in par. (b), responsible parties shall use all of the criteria in sub. (4) to further evaluate appropriate remedial action options that have been identified for further evaluation under sub. (2), for each contaminated medium or migration or exposure pathway. This evaluation process shall be used to determine which remedial action option constitutes the most appropriate technology or combination of technologies to restore the environment, to the extent practicable, within a reasonable period of time and to minimize the harmful effects of the contamination to the air, land, or waters of the state, to address the exposure pathways of concern, and effectively and efficiently address the source of the contamination.

Note: The purpose of the technical and economic feasibility evaluation is to evaluate a range of remedial action options suitable for a particular site or facility to determine the practicability of implementing those options. If a particular option is not suitable for a particular site or facility, such as in situ air sparging in dense clay soils, it should not be evaluated. Emphasis should be placed on remedial action options suitable for a particular site or facility. Any remedy selected should attempt to limit secondary impacts including air and water discharges, destruction of ecosystems, and excessive use of energy.

Note: For cases involving a discharge and migration of organic contaminants that do not readily degrade in soil or groundwater, an active remedial action that will reduce the contaminant mass and concentration will typically be necessary. Natural attenuation, covers, and barriers do not actively reduce contaminant mass and concentrations. Chlorinated compounds are the most common contaminants that fall under this provision. Some organic contaminants, such as PCBs and PAHs may not readily migrate, depending on site characteristics.

(am) Responsible parties shall document their evaluation of a remedial option or combination of options which would use recycling or treatment technologies that destroy or detoxify contaminants, rather than transfer the contaminants to other media.
(b) A detailed evaluation based on the criteria in sub. (4) is not required in those cases where a remedial action option identified during the initial screening results in the reuse, recycling, destruction, detoxification, treatment, or any combination thereof of the hazardous substances present at the site and this proposed option meets all of the following requirements:
1m. Is proven to be effective in remediating the types of hazardous substances present at the site, based on experience gained at other sites with similar site characteristics and conditions;
2m. Can be implemented in a manner that will not pose a significant risk of harm to human health, safety, or welfare or the environment; and
3. Is likely to result in the reduction or control, or both, of the hazardous substances present at the site to a degree and in a manner that is in compliance with the requirements of s. NR 722.09(2) to (4).

Note: Section NR 722.07(3) (b) is intended to provide a streamlined evaluation process for certain remedial actions that are presumed to meet the evaluation and selection criteria in ss. NR 722.07 and 722.09.

(4)EVALUATION CRITERIA. Except as provided in s. NR 722.07(3) (b), the remedial action options identified by the initial screening shall be evaluated based on the following requirements and in compliance with the requirements of s. NR 722.09.
(a)Technical feasibility. The technical feasibility of each appropriate remedial action option that effectively and efficiently addresses the sources of contamination shall be evaluated using the following criteria:
1. `Long-term effectiveness.' The long-term effectiveness of appropriate remedial action options, taking into account all of the following:
a. The degree to which the toxicity, mobility and volume of the contamination is expected to be reduced.
b. The degree to which a remedial action option, if implemented, will protect public health, safety, and welfare and the environment over time.
2. `Short-term effectiveness.' The short-term effectiveness of appropriate remedial action options, taking into account any adverse impacts on public health, safety, or welfare or the environment that may be posed during the construction and implementation period until case closure under ch. NR 726.
3. `Implementability.' The implementability of appropriate remedial action options, taking into account all of the following:
a. The technical feasibility of constructing and implementing the remedial action option at the site or facility given the type of contaminants and hydrogeologic conditions present.
b. The availability of materials, equipment, technologies, and services needed to conduct the remedial action option taking into account the location and environmental impact of the selected materials and equipment.
c. The potential difficulties and constraints associated with on-site construction or off-site disposal and treatment.

Note: For example, evaluate the use of heavy equipment and cost of fuel to transport wastewater and leachate from a site compared to on-site treatment.

d. The difficulties associated with monitoring the effectiveness of the remedial action option.
e. The administrative feasibility of the remedial action option, including activities and time needed to obtain any necessary licenses, permits or approvals.
f. The presence of any federal or state, threatened or endangered species.
g. The technical feasibility of recycling, treatment, engineering controls or disposal.
h. The technical feasibility of naturally occurring biodegradation at the site or facility, if responsible parties evaluate this option.
i. The redevelopment potential of the site once the remedy has been implemented.
j. Reduction of greenhouse gases consistent with federal or state climate action policies.
4. `Restoration time frame.' The expected time frame needed to achieve the necessary restoration, taking into account all of the following qualitative criteria:
a. Proximity of contamination to receptors.
b. Presence of sensitive receptors.
c. Presence of threatened or endangered species or habitats, as defined by state and federal law.
d. Current and potential use of the aquifer, including proximity to private and public water supplies and surface water bodies.
e. Magnitude, mobility and toxicity of the contamination.
f. Geologic and hydrogeologic conditions.
g. Effectiveness, reliability, and enforceability of continuing obligations.
h. Naturally occurring biodegradation processes at the site or facility which are expected to reduce the total mass of contamination in an effective and timely manner and which have been demonstrated to be occurring at the site or facility, to the satisfaction of the department in the site investigation report.
i. The degradation potential of the compounds.

Note: The biogeochemical environment and the contaminant of concern are critical factors in determining degradation potential. Not all compounds readily degrade in soil or groundwater, while others, such as certain petroleum compounds have a greater degradation potential.

Note: The purpose of s. NR 722.07(4) (a) 4. is to provide criteria to determine how quickly environmental laws and standards must be achieved, due to the site-specific hazards that the contamination poses. It is not intended to authorize risk assessments, nor is it the intent of this provision to establish a generic time period that would be applied at all sites or facilities.

(b)Economic feasibility. The economic feasibility of each appropriate remedial action option that effectively and efficiently addresses the source of the contamination shall be evaluated, using the following criteria:
1m. Capital costs, including both direct and indirect costs;
2m. Initial costs, including design and testing costs;
3. Annual operation and maintenance costs;
4. Total present worth of the costs for all national priority list sites or facilities; sites or facilities where the department has entered into a contract pursuant to s. 292.31(1) (b), Stats.; and sites or facilities where state environmental fund monies are being expended; and
5. Costs associated with potential future liability.
(5)ADDITIONAL REQUIREMENTS.
(a)Engineering controls. If engineering controls are considered, responsible parties shall, at a minimum, evaluate an on-site engineering control to address all hazardous substances, contaminated media and migration or exposure pathways.

Note: Engineering controls include on-site or off-site containment methods, such as covers, soil covers, engineered structures, liners, gas collection systems, armoring of sediments, erosion controls, vapor mitigation systems, and groundwater slurry walls. Restricting access to a site or facility, such as constructing a fence, is not an engineering control.

(b)Continuing Obligations. Responsible parties shall consider the appropriateness of using continuing obligations to ensure that adequate protection of public health, safety, and welfare and the environment is maintained over time.
(c)Additional requirements. Responsible parties shall comply with additional site-specific remedial action evaluation or documentation requirements that may be specified by the department due to the complexity of the site or facility, the persistence of certain compounds, or the severity of the potential or actual public health or environmental impacts.

Wis. Admin. Code Department of Natural Resources NR 722.07

Cr. Register, April, 1995, No. 472, eff. 5-1-95; CR 12-023: am. (3) (a), cr. (3) (am), am. (b) (intro.), r. (3) (b) 1., 2., renum. (3) (b) 2. a. to c. to (3) (b) 1m, 2., 3. and am. (3) (b) 3., am. (4) (a) (intro.), 3. a., b., cr. (4) (a) 3. i., j., am. (4) (a) 4. d., g., cr. (4) (a) 4. i., am. (4) (b) (intro.), r. (4) (b) 1., renum. (4) (b) 1. a. to e. to (4) (b) 1m., 2m., 3., 4., 5. and am. (4) (b) 4., r. (4) (b) 2., am. (5) (b), (c) Register October 2013 No. 694, eff. 11-1-13.