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Soil Pile Disposition Assessment
Section 8 - Description of Corrective Measure Standards and Evaluation Criteria
The EPA established nine criteria in the NCP that is typically used in evaluating remediation technologies for compliance with the statutory requirements (EPA, 1990). These evaluation criteria are as follows:
Attainment of Cleanup Standards. The ability to attain media cleanup standards set by state or federal regulations.
Protection of Human Health and Environment. Protection of human health and environment is assessed based on the overall effectiveness of the alternative to block pathways for human exposure to the contamination.
Control the Sources of Releases. The ability to stop further environmental degradation by controlling or eliminating further releases that may pose a threat to human health and/or the environment is used to define the ability to control the source of release.
Short-Term Impacts. Risk of short-term pollution exposure, physical injury and damage to site workers, community residents, community structures, and the greater environment during implementation is considered for the remediation technology.
Long-Term Impacts. The ability to protect human health and the environment over the long term. Assessment of long-term effectiveness and permanence includes the durability of actions to block pollutant pathways and the minimization of monitoring requirements.
Implementability. Site conditions, project time requirements, and service availability that effect remedial design. The complexity of land use restrictions, administrative responsibilities, regulatory approval, and long-term monitoring obligations are also considered.
Reduction of Toxicity, Mobility, and Volume. The evaluation of toxicity, mobility, and volume was based on the degree to which the metals and explosive contaminants were contained, treated, or removed from the site.
Cost. Cost estimations are based upon published cost estimation guides and engineering experience. A detailed development of the cost estimates is presented in Section 9.
Compliance with Waste Management Standards. A discussion of specific waste management activities required for the remedial technology is included.
8.1 - Remedial Action Objectives
The results of the site investigation and interim measures action for SWMUs B-8, B‑20/21, B-24, B-28 and the DD Area indicate that soils are the media of concern. The RAOs for the SWMUs are as follows:
Prevent ingestion or inhalation by outdoor workers of soils with contaminant levels above appropriate PCLs.
Reduce concentrations of metals of concern in soils to below PCL residential standards.
Minimize potential short-term and long-term exposure resulting from remedial activities.
8.2 -Detailed Alternative Evaluations
The following sections discuss the alternatives retained after the screening analysis as they relate to the assessment criteria.
8.2.1 Alternative 1: No Action
A detailed evaluation of this alternative considering the threshold and primary balancing criteria discussed above is presented in Table 8.1. There are no costs associated with this alternative. Overall protection of human health and the environment is not necessarily met by this alternative. Current data indicate that contaminants are present above established background levels and chemical specific PCLs in the stockpiled soils at the SWMUs of concern. With this option, it will not be known if nearby populations or the environment are exposed to contaminated soils in the future. Measures to protect human health and the environment against exposure to potentially contaminated soils will not be taken.
The long-term effectiveness criterion is not met by this alternative. Adequate and reliable controls will not be used to protect against potential future use of the sites.
Table 8.1 - Detailed Assessment of the No Action Alternative
| Evaluation Criteria | Assessment Factors | General Comments |
| Overall protection of human health and the environment | How risks are eliminated, reduced, or controlled | Overall protection of human health and the environment is not necessarily met by this alternative. |
| Attainment of Clean-up Standards | Chemical specific | Does not comply with chemical criteria where contaminants are above the calculated PCLs. |
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| Location specific | Complies with requirements to protect endan�gered species, antiquities, and historical sites. |
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| Action specific | No action-specific attainment of standards as there are no remedial actions. |
| Long-term effectiveness and permanence | Magnitude of residual risk and reliability of controls | Residual risk remains. |
| Reduction of toxicity, mobility, and volume | Expected reductions in toxicity, mobility, and volume | There is no expected reduction in toxicity, mobility, or volume with this alternative. |
| Short-term effectiveness | Environmental impacts | Not applicable |
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| Worker and community protection | No short-term risks, because no exposure pathways are complete. |
| Implementability | Ability to construct and maintain | Not applicable. |
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| Ability to monitor effectively | No monitoring will be done. |
The no-action alternative does not reduce the mobility, toxicity, or volume of the contaminants. The volume of the contaminated soil may actually increase but become more diluted as the contaminants migrate.
There are no short-term risks to workers and the community because no construction activities are anticipated at these SWMUs, and the community does not have access to these sites. There are no environmental impacts associated with implementation of this plan.
The alternative is easily implemented. There are no capital or operating costs associated with the no-action alternative. However, there may be unknown liability costs.
8.2.2 Alternative 3: Excavation, Treatment, and Off-site Disposal
Overall protection of human health and the environment will be provided by this alternative through treatment of the soil, as necessary, and transporting soils to an appropriate off-site land disposal facility. This alternative has already been implemented as an interim measure for the SWMU B-20/21 sifted soils.
As shown in Table 8.2, the chemical-specific ARARs will be met as the contaminated soil is removed and treated. Other location and action-specific ARARs will also be followed during the construction and maintenance phases of the remedial action.
The toxicity of the contaminants will be reduced through removal actions. The volume of the contaminated soil will be reduced by removal and treatment of the contaminated soils. Mobility of the contaminants in the soils is reduced by treatment of the soils with phosphate material from the PIMS technology.
Short-term risks to workers and the community are not expected. Potential exposure risk during construction or treatment activities will be reduced using engineering controls.
The estimated capital costs for this alternative, which includes stabilization of approximately 5 percent of the sifted soils. The costs are detailed in Section 9 - Comparative Analysis and Alternative Selection.
The remedial alternatives for the sifted soils generally compare favorably with the evaluation criteria. Alternative 1, no action, does not necessarily meet the criteria for overall protection of human health and the environment. The remaining alternative would meet the threshold criteria. Therefore, alternative 3 is proposed as the most appropriate remedial action.
Table 8.2 - Detailed Assessment of Excavation, Treatment, and Off-site Disposal Alternative
| Evaluation Criteria | Assessment Factors | General Comments |
| Overall protectiveness of human health and the environment | How risks are eliminated, reduced, or controlled | Future risks to human health from metal contaminants would be minimized by prevention of migration, onsite recovery and treatment of contaminated soils, and performance of confirmation sampling to monitor contaminant levels remaining at the site. Presently, no endangered species have been identified at the site; this alternative is expected to be protective of any that may be found in the future. |
| Attainment of Clean-up Standards | Chemical specific | Clean-up Standards will be met by treatment and off-site disposal of soils. |
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| Location specific | Complies with preservation of endangered species, antiquities, and historical sites requirements. |
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| Action specific | Complies with monitoring requirements. No known archeological sites at the site. The alternative is not expected to threaten any that may be found in the future. |
| Long-term effectiveness | Magnitude of residential risk | The soil recovery and treatment alternative would reduce contaminant levels faster than other alternatives. Residual risk would be low. |
| Reduction of toxicity, mobility, or volume | Amount destroyed or treated | Contaminated concentrations in the soil would be reduced via recovery and treatment. |
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| Irreversible treatment | Soil contaminant treatment with off-site disposal is irreversible. |
| Short-Term Effectiveness | Environmental Impacts | There is expected to be minimal environmental impact with the use of this alternative |
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| Worker and Community Protection | Minimal short-term risks with the use of engineering controls to reduce exposure of dust to workers. |
| Implementability | Ability to construct and maintain | Easily implemented. |
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| Ability to monitor effectively. | No monitoring will be done. Samples to provide assurance of waste treatment goals being met will be taken. |