Cleanup Options Considered By EPA
According to the EPA there were 9 different proposals for treatment of the
waste at this site. This list was narrowed to only 7 for consideration.
The EPA considered 7 different cleanup models. The first two, No Action
and Institutional Controls, were not realistic contenders but are always
considered. No Action would mean simply walking away from any further oversight
or regulatory attempts. Institutional controls would be simply locking the gate
and posting signs.
Alternative 3 involves consolidation and cover. Consolidation means to dig
up all of the waste on the site into a single large pile. A cover is a layer of
soil and vegetation to prevent the top of the dumpsite from easily eroding by
wind and water action. Since the top of the pile would be well above ground (to
40 feet) in some scenarios wind action could disperse toxins some distance from
the site. Also, a cover allows water to percolate through the consolidated
material. Since the water would move through dozens of feet of toxic material it
would have the opportunity to dissolve toxins and carry it to the groundwater.
Alternative 4 is identical to Alternative 3, but uses a "cap"
instead of a cover. A cap is an engineered layered system that seals the top
surface from wind and water erosion. The system further employs a drainage
system to keep the toxic waste very dry, and therefore less likely to move into
the water column.
Both Alternative 3 and 4 leave highly toxic waste in contact with the
groundwater.
Alternative 5 employs both consolidation and capping. In addition, the
base material in some areas is treated using in situ stabilization. In Situ
methodology employs underground mixing of waste and concrete to solidify the
waste. This meets the feasibility
criteria for reduction of mobility at low cost.
Alternative 6 used consolidation, a cap, and pump-and-treat
groundwater processing. This alternative differs from alternative 5 in
that the material in contact with the groundwater
is treated by cycling water through the dumpsite. No solidification is
used in this process. In some ways this alternative is more desirable since
potential migration to groundwater is fully eliminated. However, pump-and-treat
is a short-term criteria, whereas in situ
solidification is a long-term treatment. The EPA rejected Alternative 6 on the
grounds that the groundwater is not significantly impacted relative to local
receptors. Also, the State of Florida wishes long-term studies on the potential
impact to the Anclote River.
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