Widows Creek fossil plant assessment of potential effects on groundwater of the Phase 2 FGD pond

The proposed Phase 2 disposal area for FGD wastes lies approximately 1.5 miles northeast of the Widows Creek main plant and immediately northeast of the existing Phase 1 site. The objective of this assessment was to analyze the impact to local groundwater from the disposal facility based upon a reevaluation of existing data. A numerical model was used to approximate regional groundwater movement and to estimate mounding effects of the disposal facility. The formation of a groundwater mound beneath the area will alter groundwater flow patterns in the site vicinity and the groundwater levels of nearby wells will probably be affected. Considering that Widows Creek Fossil Plant is situated in a karst terrane, special precautions should be taken in design and construction of the proposed disposal facility to minimize the impact to water and groundwater resources. Recommendations are provided for design features and followup monitoring that ensure an elevated level of protection for nearby domestic water supplies, Widows Creek and other associated water and groundwater resources. In general, modeling results indicate that leachate migration will result in insignificant effects on nearby surface waters. 18 refs., 5 figs.