131 LA UR 03 5862 - National Nuclear Security Administration ...

The sludge and water in the lagoons and surrounding area were sampled and analyzed in four separatesampling events. The DOE conducted the first in 1988, then LANL conducted several in 1991/1992,1994/1995, and 1999/2000. The contaminants of potential concern found included cobalt-60, cesium-134,strontium-90, sodium-22, and tritium. Other inorganic and organic chemicals identified were lead, mercury,and polychlorinated biphenyls.Approximately 5,000 cubic yards of contaminated material (sludge and clay liner) from the two northernlagoons were removed in 2002. The sludge and clay liners contained radioisotopes (e.g., cobalt-60 andcesium-134) and carcinogens (Aroclor-1260) at levels exceeding the target levels of 15 millirem per year fordose and 10 -5 risk. One hundred and fifty-nine waste bins were filled with northeast lagoon waste and 230waste bins from the northwest lagoon. Approximately 90 cubic yards of soil were removed from the lagoonsoutfall area located on the eastern side. Miscellaneous debris, from a previous interim action, filled anotherthree waste bins.Lagoon remediation efforts almost completed at LANSCESource RemovalsA voluntary corrective action (VCA) was performed at the Burn Ground North as part of the MDA-Pclosure activities during FY 2002. VCAs were also completed at areas of concern (AOCs) 21-030 and C-21-015, and at solid waste management unit (SWMU) 54-007(a). Additionally, approximately 1,500 cubicfeet of contaminated soil was removed and site restoration was completed at the TA-16-260 outfall. Allcontaminated soils were removed and disposed of in accordance with applicable EPA, NMED, DOE, andLANL requirements. VCA completion reports were prepared for AOCs 51-001 and 54-007(d), SWMU54-007(c)-99, and the Los Alamos Area Office Land Transfer Tract (which included PRSs 0-003, 0-012,and 0-030(i)) and submitted to the appropriate administrative authority (NMED for Hazardous and SolidWaste Amendment [HSWA] PRSs, and DOE for non-HSWA PRSs) with a recommendation for NFA.NMED concurred with the recommendation for NFA at the Los Alamos Area Office Land Transfer Tractfor the two HSWA PRSs, based on a review of the VCA completion report. DOE also concurred with therecommendation for NFA for the one non-HSWA PRS.Continued Field InvestigationsThe ER Project continued investigations in several areas during FY 2002, including the following:• completed four rounds of well sampling and two rounds of biota sampling to monitor naturalattenuation and to support the ER Project’s collaboration with San Ildefonso Pueblo,• completed the drilling and installation of one monitoring well, R-13. Additionally, the ER Projectcompleted the report on hydrologic tests at characterization wells R-9i, R-13, R-19, R-22 and R-31;2-182SWEIS Yearbook—2002