Closure Report for Corrective Action Units 530, 531, 532, 533, 534, 535: NTS Mud Pits, Nevada Test Site, Nevada, Rev. No.: 0
This Closure Report (CR) presents information supporting the recommendation of no further action for the following six Corrective Action Units (CAUs): (1) CAU 530 - LANL Preshot Mud Pits; (2) CAU 531 - LANL Postshot Mud Pits; (3) CAU 532 - LLNL Preshot Mud Pits; (4) CAU 533 - LLNL Postshot Mud Pits; (5) CAU 534 - Exploratory/Instrumentation Mud Pits; and (6) CAU 535 - Mud Pits/Disposal Areas. This CR complies with the requirements of the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996) that was agreed to by the State of Nevada, the U.S. Department of Energy, and the U.S. Department of Defense. CAUs 530-535 are located in Areas 1-10, 14, 17, 19, and 20 of the Nevada Test Site and are comprised of 268 Corrective Action Sites (CASs) listed in Table 1-1. The purpose of this CR is to validate the risk-based closure strategy presented in the ''Mud Pit Risk-Based Closure Strategy Report'' (RBCSR) (NNSA/NSO, 2004) and the CAUs 530-535 SAFER Plan (NNSA/NSO, 2005b). This strategy uses 52 CASs as a statistical representation of CAUs 530-535 to confirm the proposed closure alternative, no further action, is sufficient to protect human health and the environment. This was accomplished with the following activities: A field investigation following a probabilistic sampling design to collect data that were used in a non-carcinogenic risk assessment for human receptors; Visual habitat surveys to confirm the lack of habitat for threatened and endangered species; Disposal of debris and waste generated during field activities; and Document Notice of Completion and closure of CAUs 530-535 issued by Nevada Division of Environmental Protection. The field investigation and site visits were conducted between August 31, 2005 and February 21, 2006. As stated in the RBCSR and Streamlined Approach for Environmental Restoration (SAFER) Plan, total petroleum hydrocarbons-diesel-range organics (TPH-DRO) was the only contaminant of potential concern identified for CAUs 530-535. This analyte was detected in 22 percent of the soil samples, but the risk assessment confirmed that the reported levels did not pose an unacceptable risk to human receptors (i.e., the associated Hazard Index for each CAS is {le} 1.0). A data quality assessment was performed on the collected TPH-DRO data to confirm they were of sufficient quality and quantity to satisfy the data quality objective decisions. The collected dataset met all the criteria specified in the SAFER Plan. Visual habitat surveys were conducted at 201 CASs and confirmed that the mud pit CASs are not suitable habitat for threatened or endangered species. Based on these activities, there is also no unacceptable risk to ecological receptors. These results support the recommended closure alternative of no further action for the 268 CASs within CAUs 530-535.
- Research Organization:
- Stoller-Navarro Joint Venture
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- DE-AC52-03NA99205
- OSTI ID:
- 891965
- Report Number(s):
- DOE/NV-1131; TRN: US200622%%480
- Country of Publication:
- United States
- Language:
- English
Similar Records
Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 544: Cellars, Mud Pits, and Oil Spills, Nevada Test Site, Nevada, Revision 0
Closure Report for Corrective Action Unit 357: Mud Pits and Waste Dump, Nevada Test Site, Nevada, Rev. No.: 0