Record of Decision Remedial Alternative Selection for the C, F, K, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P)

The C-, F-, K-, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P) (C-, F-, K-, and P-CPRBs) waste units are listed as Resource Conservation and Recovery Act (RCRA) 3004(u) Solid Waste Management Units/Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) units in Appendix C of the Federal Facility Agreement (FFA) for the Savannah River Site (SRS). The C-, F-, K-, and P-CPRBS comprise a single operable unit which was remediated under an early removal action during the summer of 1997. Slightly elevated levels of naturally occurring metals and radionuclides in the coal-laden sediments and shallow soils were confined to the 0-1 foot interval below the basin floor. These source materials were identified as low level threat wastes. Under the Removal Site Evaluation Report/Wastewater Closure Plan for the C-, F-, K-, and P-Area Coal Pile Runoff Basins (189-C, 289-F, 189-K, and 189-P) (U) (WSRC 1997b), the coal-laden sediments and shallow soils were removed from each of the four basins during the summer of 1997. At least four feet of clean backfill was placed in each basin to restore the area to the surrounding grade. This removal action completely freed the four CPRBS of the source material for the constituents of concern and the sulfide minerals, which were reducing the pH of the infiltrate. Because the source material has been removed from the CPRBs, releases of hazardous substances will not occur from this operable unit and there is no imminent or substantial endangerment to public health, welfare, or the environment