Closure Report for Corrective Action Unit 135: Areas 25 Underground Storage Tanks, Nevada Test Site, Nevada

Cox, D. H.

Bechtel Nevada (Firm)

关键词: Hydrocarbons;    Radioisotopes;    02 Petroleum;    Decontamination;    Liquid Wastes;   

DOI  :  10.2172/793213
RP-ID  :  DOE/NV--717-Rev 1
RP-ID  :  AC08-96NV11718
RP-ID  :  793213

美国|英语

来源: UNT Digital Library

【 摘 要 】

Corrective Action Unit (CAU) 135, Area 25 Underground Storage Tanks, was closed in accordance with the approved Corrective Action Plan (DOE/NV, 2000). CAU 135 consists of three Corrective Action Sites (CAS). Two of these CAS's were identified in the Corrective Action Investigation Data Quality Objective meeting as being improperly identified as underground storage tanks. CAS 25-02-03 identified as the Deluge Valve Pit was actually an underground electrical vault and CAS 25-02-10 identified as an Underground Storage Tank was actually a former above ground storage tank filled with demineralized water. Both of these CAS's are recommended for a no further action closure. CAS 25-02-01 the Underground Storage Tanks commonly referred to as the Engine Maintenance Assembly and Disassembly Waste Holdup Tanks and Vault was closed by decontaminating the vault structure and conducting a radiological verification survey to document compliance with the Nevada Test Site unrestricted use release criteria. The Area 25 Underground Storage Tanks, (CAS 25-02-01), referred to as the Engine Maintenance, Assembly, and Disassembly (E-MAD) Waste Holdup Tanks and Vault, were used to receive liquid waste from all of the radioactive and cell service area drains at the E-MAD Facility. Based on the results of the Corrective Action Investigation conducted in June 1999, discussed in ''The Corrective Action Investigation Plan for Corrective Action Unit 135: Area 25 Underground Storage Tanks, Nevada Test Site, Nevada'' (DOE/NV, 199a), one sample from the radiological survey of the concrete vault interior exceeded radionuclide preliminary action levels. The analytes from the sediment samples exceeded the preliminary action levels for polychlorinated biphenyls, Resource Conservation and Recovery Act metals, total petroleum hydrocarbons as diesel-range organics, and radionuclides. The CAU 135 closure activities consisted of scabbling radiological ''hot spots'' from the concrete vault, and the drilling removal of the cement-lined vault sump. Field activities began on November 28, 2000, and ended on December 4, 2000. After verification samples were collected, the vault was repaired with cement. The concrete vault sump, soil excavated beneath the sump, and compactable hot line trash were disposed at the Area 23 Sanitary Landfill. The vault interior was field surveyed following the removal of waste to verify that unrestricted release criteria had been achieved. Since the site is closed by unrestricted release decontamination and verification, post-closure care is not required.