Ecological Risk Assessment Step 8
The final step in the Ecological Risk Assessment Guidance for Superfund (ERAGS) 8-step process
is Risk Management. This is the stage where decisions are made about what remedial (clean-up)
actions should be taken. Nine criteria must be taken into consideration when making these
decisions.
Threshold Criteria - take precedence
over other categories |
- Overall protection of human health and the environment;
- Compliance with applicable or relevant and appropriate
requirements (ARARs) - ARARs are such things as cleanup
levels mandated by state agencies, compliance with laws such
as the Endangered Species Act, Clean Water Act, or Clean Air
Act;
|
Balancing Criteria |
- Long-term effectiveness and permanence - will the results of the remedial action last over the long-term;
- Reduction of toxicity, mobility, or volume of hazardous
wastes through the use of treatment - will the cleanup activity
actually work at reducing the amount or toxic effects of the
contaminants;
- Short-term effectiveness - what are the effects during
the treatment/cleanup; what is the potential for additional
releases of toxins into the environment;
- Implementability - is it practical to do the particular
cleanup remedy;
- Cost - is the remedy cost-effective, especially compared
to other remedial choices;
|
Modifying Criteria |
- State acceptance - do the state agencies accept the
remedy;
- Community acceptance - is the public willing to go
along with the remedial action.
|
Different remedies may be suggested at this stage, such as removal of
contaminated media (soil, sediment), water treatment plants, capping of
contaminated areas with clean materials, on-site incineration of contaminated
media, bioremediation (in which organisms such as bacteria break down
the contaminants), or monitored natural attenuation (MNA). MNA is where
the site is simply left alone and monitored over time, allowing the contaminants
either to wash away, break down, or otherwise disappear from the site
without any active remediation.