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.
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.
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.
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.
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.
Wis. Admin. Code Department of Natural Resources NR 722.07