Streamlined Approach for Environmental Restoration Closure Report for Corrective211 Action Unit 495: Unconfirmed Joint Test Assembly Sites Tonopah Test Range, Nevada

摘要

This report addresses the closure of Corrective Action Unit (CAU) 495,211u001eUnconfirmed Joint Test Assembly (JTA) Sites identified in Appendix III of the 211u001eFederal Facility Agreement and Consent Order (FFACO). The site is located at the 211u001eTonopah Test Range in south central Nevada. CAU 495 consists of two Corrective 211u001eAction Sites (CASS), CAS Number (No.) TA-55-O07-09SE (Buried Artillery Round No. 211u001e3) and CAS No. TA-55-006-09SE (Buried Artillery Round No. 4). Both CASS were 211u001ebelieved to be the impact sites of failed artillery round test packages 211u001econtaining depleted uranium (DU) and high explosives (HE). Closure activities 211u001ebegan on November 16, 1998, with the installation of three-strand barbed wire 211u001efence around each site. Excavation activities began on November 22, 1998, at CAS 211u001eTA-55-007-09SE (DU Round No. 3). A backhoe was used to excavate two areas that 211u001ewere possible locations for the artillery round. Excavation revealed no 211u001eradiologically impacted soil, ordnance related debris, or HE residue. Closure 211u001eactivities at CAS TA-55-006-09SE (DU Round No. 4) began on November 22, 1998, and 211u001ewere conducted using the same procedures as those for DU Round No. 3. At 211u001eapproximately 1.2 meters (4 feet), a nose cone identified as being from a DU 211u001eartillery round was uncovered. However, it contained no explosive residue or 211u001eradiological contamination. The surrounding soil was also free from radiological 211u001econtamination and HE residue. A second location was also excavated and contained 211u001eno radiologically impacted soil, ordnance related debris, or HE residue. After a 211u001epreliminary geophysical survey determined that no artillery rounds were present 211u001ebelow the excavated depths and no contamination existed, the fencing was removed 211u001eand the excavations were backfilled, compacted to 80 percent, and graded. The 211u001elocations were then staked and surveyed. A final geophysical survey was run on 211u001eMarch 3-4, 1999. The results indicated no anomalies below the excavated depth of 211u001ethe excavations. Closure for this CAU was completed in accordance with the 211u001eapproved Streamlined Approach for Environmental Restoration Work Plan as a clean 211u001eclosure. Therefore, the U.S. Department of Energy, Nevada Operations Office 211u001erequests that a Notice of Completion be issued by the Nevada Division of 211u001eEnvironmental Protection, and the Unconfirmed JTA Sites, CAU 495, be moved from 211u001eAppendix III to Appendix IV of the FFACO Closed Corrective Action Units.