After New Mexico again in November suspended certain Department of Energy efforts to control a hexavalent chromium plume at the Los Alamos National Laboratory, the manager of federal legacy cleanup there said last week the parties are looking for solutions.
On Nov. 18, the New Mexico Environment Department (NMED) withdrew its temporary authorization for continuation of DOE’s interim measure to control the plume. The interim measure has involved pumping clean groundwater underground in an effort to control the plume.
But before Thanksgiving, NMED withdrew its approval in a letter to Jessica Kunkle, the head of DOE’s Environmental Management office for Los Alamos.
The state cited “recent analytical results showing the sole source regional aquifer beneath the Pueblo de San Ildefonso exhibits hexavalent chromium concentrations exceeding the regulatory standards” set out in the New Mexico administrative code.
“NMED is directing DOE to immediately cease all injection operations effective as of the date of this letter,” according to the November letter. The state had earlier blocked the injection in 2023.
But since then, DOE and NMED officials have been in touch seeking to craft a solution, Kunkle told DOE’s Northern New Mexico Advisory board last week.
Kunkle said DOE and NMED are actively collaborating on the plume issue. DOE Environmental Management and the state have formed an “adaptive site management work group.” The group will meet quarterly. The first session was held in October and the second in January, Kunkle said.
The source of the plume dates to the 1950s through the 1970s when a “corrosion inhibitor” was used to clean pipes and cooling towers at non-nuclear power plants, Kunkle said. The plume is more than 1,000 feet underground.
The interim measure that DOE has been employing is basically a pump-and-treat system that seeks to contain the plume within laboratory property.