Corrective Action Decision Document for Corrective Action Unit 151: Septic Systems and Discharge Area, Nevada Test Site, Nevada, Rev. No.: 0

Evenson, Grant

Stoller-Navarro Joint Venture

关键词: Reliability;    Sewage;    Recommendations;    Implementation;    Tanks;   

DOI  :  10.2172/891959
RP-ID  :  DOE/NV--1123
RP-ID  :  DEAC-5203NA99205
RP-ID  :  891959

美国|英语

来源: UNT Digital Library

【 摘 要 】

This Corrective Action Decision Document has been prepared for Corrective Action Unit (CAU) 151, Septic Systems and Discharge Area, at the Nevada Test Site, Nevada, according to the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996). Corrective Action Unit 151 is comprised of eight corrective action sites (CASs): (1) CAS 02-05-01, UE-2ce Pond; (2) CAS 12-03-01, Sewage Lagoons (6); (3) CAS 12-04-01, Septic Tanks; (4) CAS 12-04-02, Septic Tanks; (5) CAS 12-04-03, Septic Tank; (6) CAS 12-47-01, Wastewater Pond; (7) CAS 18-03-01, Sewage Lagoon; and (8) CAS 18-99-09, Sewer Line (Exposed). The purpose of this Corrective Action Decision Document is to identify and provide the rationale for the recommendation of corrective action alternatives (CAAs) for each of the eight CASs within CAU 151. Corrective action investigation (CAI) activities were performed from September 12 through November 18, 2005, as set forth in the CAU 151 Corrective Action Investigation Plan and Record of Technical Change No. 1. Additional confirmation sampling was performed on December 9, 2005; January 10, 2006; and February 13, 2006. Analytes detected during the CAI were evaluated against appropriate final action levels (FALs) to identify the contaminants of concern for each CAS. The results of the CAI identified contaminants of concern at two of the eight CASs in CAU 151 and required the evaluation of CAAs. Assessment of the data generated from investigation activities conducted at CAU 151 revealed the following: (1) Soils at CASs 02-05-01, 12-04-01, 12-04-02, 12-04-03, 12-47-01, 18-03-01, 18-99-09, and Lagoons B through G of CAS 12-03-01 do not contain contamination at concentrations exceeding the FALs. (2) Lagoon A of CAS 12-03-01 has arsenic above FALs in shallow subsurface soils. (3) One of the two tanks of CAS 12-04-01, System No.1, has polychlorinated biphenyls (aroclor-1254), trichloroethane, and cesium-137 above FALs in the sludge. Both CAS 12-04-01, System No.1 tanks contain trichloroethane and 1,4-dichlorobenzene above ''Resource Conservation and Recovery Act'' toxicity characteristic limits. Based on the evaluation of analytical data from the CAI, review of future and current operations at the eight CASs, and the detailed and comparative analysis of the potential CAAs, the following corrective actions are recommended for CAU 151. No Further Action is the recommended corrective action for soils at CASs 02-05-01, 12-04-01, 12-04-02, 12-04-03, 18-03-01, and 18-99-09; and Lagoons C, D, F, and G of CAS 12-03-01. No Further Action with implementation of a best management practice (BMP) is recommended for soils at CAS 12-47-01 and Lagoons B and E of CAS 12-03-01. To be protective of future workers should the present scenario used to calculate FALs change, an administrative use restriction will be recorded per the FFACO agreement as a BMP. Close in Place with Administrative Controls is the recommended corrective action for Lagoon A of CAS 12-03-01. Based on the evaluation of analytical data from the CAI; review of future and current operations at CASs 12-04-01, 12-04-02, and 12-04-03; and the detailed and comparative analysis of the potential CAAs, the following corrective actions are recommended for the septic tanks at these CASs. No Further Action with implementation of BMPs is the recommended corrective action for septic tanks that do not contain potential source material from CAS 12-04-01, System No.4 (four tanks); CAS 12-04-02, System No.5 (six tanks); and CAS 12-04-03, System No.3 (four tanks). Clean Closure with implementation of BMPs is the recommended corrective action for the septic tanks from CAS 12-04-01, System No.1 (two tanks). The preferred CAAs were evaluated on technical merit focusing on performance, reliability, feasibility, safety, and cost. The alternatives were judged to meet all requirements for the technical components evaluated. The alternatives meet all applicable federal and state regulations for closure of the site and will reduce potential exposure pathways to the contaminated media to an acceptable level at CAU 151.