Building 4100 - Trench SWMU
This page describes the RCRA (chemical) cleanup of the Building 4100 solid waste management unit (SWMU).
The 4100 Trench was dug in 1959 and was used for the burning of construction debris from surrounding buildings from 1959 into the 1960s. Because of this historical practice, the area is identified as a solid waste management unit (SWMU) and is included in the RCRA Corrective Action under the oversight of the DTSC.
A radiological survey of the 4100 Trench area was performed in 1988 and concluded that the area met the criteria for unrestricted release.
In 1999 during the RFI sampling some asbestos containing materials and soils impacted with copper, mercury, zinc, and lead were removed. As an precaution additional radiological surveys and soil sampling were also performed during this time. Excavated debris was surveyed and wipe tests were taken to detect radiological contamination. None was found; all results were non-detect for radioactive contamination. The material removed was disposed of at a Class 1 landfill.
DOE has submitted an RFI report to DTSC and is working with the agency to complete the closure activities.
See the Building 4100 history page for additional information on past radiological cleanup.
