4.4.6.7   Cost -- Alternative 6

The combined total capital and O&M costs, and NPV for in situ and
ex situ bioremediation are shown in Table 4-13a and 4-13b,
respectively, and detailed in Appendix C.  Total combined fixed
costs are $3,763,000 for both scenarios.  When the ex situ
biennial costs are annualized, the annual combined O&M costs are
$1,357,000 and $1,507,000 for Scenario 1 and 2, respectively. 
The NPV has been estimated for a period of 11 years for ex situ
and 2 years for in situ bioremediation discounted at a rate of
7.5 percent.  The NPV of all costs for Alternative 6 including
material handling costs and treatment and disposal costs is 
69,200,000 and $96,700,000 for Scenario 1 and 2, respectively.