SWMU Demo Dud Area (DD) Area

RL83 Interim Measures Work Plan Addendum, August 1999

Previous Investigations (Updated): As described above, potential UXO items at the site were investigated, identified and removed from 4 February 1997 to 30 May 1997. The site consists of one trench that was excavated for removal of waste scrap metal and UXO mixed in the soil. The material was excavated and sifted to remove the metal scrap to the greatest extent possible. In addition, a trailer-mounted electromagnet was pulled over the excavated material to remove scrap metal. Approximately 600 cubic yards of material was excavated.

Data Needs: Previously-sifted soils will be assessed to determine a viable method for disposition.

Interim Measures Activities:

Sifted soils at SWMU DD Area will be sampled and analyzed to provide information for the assessment of treatment/disposal options. Samples will be analyzed for metals, VOCs, SVOCs, explosives, physical parameters (density, porosity, etc.), and TCLP metals. Approximately one sample per 200 cubic yards of sifted soils will be collected.

An assessment for the proper disposition of the previously sifted soil piles will be conducted within budgeting constraints. The assessment will include a review of the bench-scale treatability study results for SWMU B-20, a review of the analytical data for SWMU DD Area, an evaluation of treatment and disposal options with regard to effectiveness; implementability; cost; reduction of mobility, toxicity, or volume; compliance with ARARs; and overall protection of human health and the environment. The assessment will also evaluate if a CAMU would be appropriate for treating CSSA soils.

A Soil Pile Disposition Assessment Report will be prepared documenting the evaluation of treatment and disposal options. The Report will recommend a treatment option for the DD Area soils and if CSSA should apply to establish a CAMU.

If the Disposition Assessment Report indicates that a CAMU is appropriate for treating CSSA soils, a CAMU application will be prepared. The CAMU application will be prepared as a separate document from the Disposition Assessment Report.

After the Disposition Assessment Report has been prepared, a treatability study of the recommended treatment option will be conducted. One cubic yard of soil (three 55-gallon drums) from SWMU DD Area will be treated during the treatability study.

After the treatability study has been completed, a treatability study report will be prepared documenting results of the study.