County negotiates interim measures to manage chromium contamination near Los Alamos

The Los Alamos County Board of Public Utilities meeting on April 16, 2025, focused on critical updates regarding groundwater contamination and remediation efforts in the region. Key discussions centered on the ongoing monitoring and treatment of chromium contamination, particularly in relation to the Prebletus and Ildefonso areas.

A significant point raised was the slow progress in drilling new monitoring wells, with only one successful completion since January 2022. The board emphasized the need to accelerate the drilling schedule to better characterize the contamination's extent and develop a more effective treatment system. Currently, approximately 60,000 pounds of potassium have been identified as having entered the canyon, with only about 2,000 pounds removed to date.

The board also discussed recommendations from the Independent Review Team (IRT), which presented strategies for interim measures to manage the chromium plume. Negotiations with the Department of Transportation (DOT) are underway to establish deadlines for implementing these measures. The board is considering alternative injection locations to enhance treatment capacity, as well as transitioning from the current modeling software, FEHM, to the more widely accepted MODFLOW model for groundwater analysis.

Concerns were raised about the potential spread of contamination, particularly towards the San Ildefonso Pueblo area. The board acknowledged that if contamination were to reach sovereign land, it would necessitate formal agreements with the Pueblo for remediation efforts. The urgency of these discussions reflects the ongoing challenges in managing groundwater contamination and the complexities involved in ensuring public safety and environmental protection.

Overall, the meeting underscored the critical need for timely action and collaboration among various stakeholders to address the contamination issues effectively. The board plans to continue monitoring progress and exploring all available options to mitigate the impact of the chromium plume on local water resources.