Removal of radioactively contaminated soil along a stretch of Middle DP Road in Los Alamos County, N.M., near a new housing complex, poses little risk to human health and should be about done this month, the Department of Energy’s Office of Environmental Management said this week.
That’s a little later than the Sept. 30 target that Brian Harcek, a senior health physicist for the DOE Environmental Management field office in Los Alamos, offered during a Los Alamos County Council work session last week.
Site cleanup contractor Newport News Nuclear-BWXT Los Alamos (N3B) and the local Environmental Management field office now expect all 124 potholes they plan to dig to be excavated by mid-October, a DOE spokesperson said by email Thursday. Crews will remove contaminated soil and debris and backfill the holes with clean soil, the spokesperson said.
This cleanup of radioactive soil is occurring along a stretch of road near the new housing, the Canyon Walk Apartments and the planned Bluffs Senior Living Apartments. The former is nearly complete but development hadn’t really started on the latter at deadline, according to materials posted on the county council’s website.
The county has commissioned a firm to produce the final design for roadway and utility infrastructure upgrades on DP Road near the housing sites by the end of December 2021. Construction was to begin in Spring 2022 and be completed by the end of 2022, according to the county.
Housing around the national laboratory has often been tight and the scope of the infrastructure work for the apartments near the impromptu DP Road cleanup includes everything from new parking to new sewer lines and a lift station.
In February 2020, radioactive contamination was detected within a 28-acre parcel of land along the public road. DOE had already declared the area fully remediated and had transferred the parcel to Los Alamos County in 2018.
Contaminated wood and other debris was found about seven feet below the surface by a Los Alamos County subcontractor digging in preparation to put in a new sewer line to serve the Canyon Walk apartment complex, which at deadline was mostly built.
With 106 of the 124 potholes excavated as of last week, the risk to people and the environment appeared low and an extensive cleanup beyond the planned soil removal wouldn’t be needed, Harcek told the county council last week. Contamination in the area has been identified as very early Manhattan Project uranium and plutonium, Harcek said in his presentation.
“Radiological contamination is adhered to the debris with little to no transfer to the surrounding soils,” Harcek said. “No further remediation is expected since soils surrounding suspect debris are being removed as a precaution.”
A New Mexico Environment Department spokesperson did not respond to a request for comment this week asking if the state agency agreed with the DOE assessment that the risk is low.
“As a conservative measure, non-contaminated debris and associated soil were packaged with newly found contaminated debris,” N3B said in a Sept. 23 update on its website. So far 2,382 cubic yards of low-level radioactive waste — the equivalent of about 9,621 55-gallon drums — has been dug up from the road and packaged for off-site disposal, the company said in the posting.
“Confirmation sampling” was planned during October, after the digging wraps up, and the contractor will deliver an assessment report to the New Mexico Environment Department Hazardous Waste Bureau by April 30, 2022, DOE’s Harcek said.
