1. Clean-up of Lincoln Park, Colorado Introduction The Source of the problem The area effected

2. Clean-up of Lincoln Park, Colorado 1958 – the Cotter Corporation began milling uranium ore outside Canon city, Colorado. Canon mill has a nominal capacity of 1,200 tons per day; –Is operated with acid or alkaline leach circuit. The mill operations produced unwanted metals and radioactive particles. Before 1980 these waste products were disposed of in unlined ponds. Contaminants leached into the groundwater, and surrounding soils. The contaminants migrated to the surrounding area including the residential area of Lincoln Park. Background;

3. Contaminants Ground Water Surface Water AirSoilOther Molybdenum Molybdenum Compounds Radium Selenium Uranium Vanadium Vanadium Compounds Lead

4. Cleanup methods used; Moving contaminated land into a lined impoundment. –Excavation of soils and moving them to a confined site.

5. Cleanup methods used; Flushing and chemically fixing contaminates in the old “pond” In situ process, selected aqueous chemicals are injected into the soils, After being contacted with contaminated material, the solution is collected using a pump – and – treat method.

6. Cleanup methods used; Constructing a ground water barrier around the soil consolidation area. Ground water

7. Soil Consolidation area

8. Cleanup methods used; Constructing a permeable reactive barrier treatment wall

9. Alternative Methods In situ Vitrification –Immobilizing metal and radonuclide contaminants in the subsurface. In situ redox –Injecting chemical reductants into the ground to create reducing conditions that immobilize the contaminants. Electrokinetic systems –An electric field is applied to the soil to either stabilize the contaminants in situ or to mobilize the for extraction. Photoremediation –Specially selected plants and grown and harvested after taking up the contaminants.