A new report calls for continued pump-and-treat operations, better technology and more cooperation between feds and New Mexico officials to combat a chromium plume at the Department of Energy’s Los Alamos National Laboratory.
That is from the executive summary of the 980-page Independent Review by a panel of 15 experts into the DOE Interim Measures used to remediate the hexavalent chromium plume in Mortandad Canyon. The report, sought by DOE and the New Mexico Environment Department, was released Dec. 31. The task force was led by Ines Triay, one-time DOE assistant secretary for the Office of Environmental Management.
First off, the panel said resumption of DOE’s interim pump-and-treat operations, already underway, was vital. Following a New Mexico order, DOE suspended the interim measure in March 2023 after “unanticipated increases in chromium concentrations in two monitoring wells, as well as the discovery of contamination deeper than expected,” according to the report.
While the ability of the interim measure (IM) system “to capture all the chromium during operations and prevent further migration on the east side is not clear, it is clear that chromium concentrations increased significantly in some wells following IM shutdown,” the panel said.
The report said DOE, the New Mexico Environment Department and the Office of State Engineer need increased cooperation and flexibility going forward.
The task force report urges the New Mexico Environment Department to “be flexible in approving alternate well locations and flow rates that optimize capture without losing containment … and evaluating options for returning cleaned treated water to the environment to support future groundwater cleanup.”
The agencies involved, including the U.S. Environmental Protection Agency, should also develop better computer models to analyze the underground plume and use improved technology to fill in existing “data gaps,” according to the report. This would set the stage for a “final remedy” for the plume, according to the task force.
The chromium plume was traced to cleaning agents used to fight corrosion at a Los Alamos power plant between the 1950s and the 1970s, according to the report. Underground chromium contamination was first discovered, via sampling and analysis, in 2004. Cleanup efforts have been regulated since 2016 under a Resource Conservation and Recovery Act order administered by the state.
