To evaluate which clean-up approach makes the most sense for a contaminated site, a number of factors and/or impacts may be considered. Typically, the ultimate goal of any remedial cleanup is to reduce risk posed to human health and the environment from exposure to the contamination.
Dump trucks were used during the dredging project to bring in clean fill after the soil was removed.
On the Housatonic, EPA established nine
factors that GE should consider when evaluating
potential clean-up approaches. These fall into
two categories: General Standards, which
are threshold factors that all alternatives must
meet; and Selection Decision Factors,
which are used as balancing factors to
evaluate the individual options.
Specifically, the General Standards include:
- Protection of human health and the
environment, taking into account the human
health and ecological risk assessments EPA
developed for the Housatonic; - Reduction or decrease of possible future releases of contamination to the environment, including the extent to which the clean-up options could mitigate the effects of a flood that could cause buried PCBs to become available to people and wildlife; and,
- Compliance with federal and state requirements.
The Selection Decision Factors — used to evaluate the risks and benefits of each individual clean-up option — include:
- Long-term reliability and effectiveness (including magnitude of residual risk; adequacy and reliability; and potential long-term adverse impacts on human health and the environment);
- Attainment of Interim Media Protection Goals (IMPGs) — clean-up goals for human health or wildlife that are determined by EPA to be protective;
- Reduction of toxicity, mobility and volume (including treatment process used and materials treated; amount of hazardous materials destroyed or treated; degree of expected reduction in toxicity, mobility or volume; degree to which treatment is irreversible; and type and quantity of residual contamination remaining after treatment);
- Short-term effectiveness;
- Implementability (including ability to construct and operate the technology; reliability of the technology; regulatory and zoning restrictions; ease of undertaking additional corrective measures, if necessary; ability to monitor the effectiveness of the remedy; coordination with other agencies; availability of suitable on-site or off-site treatment, storage, and disposal facilities and specialists; and availability of prospective technologies); and,
- Cost (including capital costs; operating and maintenance costs; and present worth costs.)
