Current Projects
Modifications to Groundwater Treatment System Requirements
The U.S. Army recently completed the Explanation of Significant Differences (ESD) for the groundwater treatment systems requirements at the Rocky Mountain Arsenal (RMA). The Environmental Protection Agency (EPA) requires public notification for any modification to a Record of Decision (ROD), which provides detailed descriptions of the environmental cleanup approach selected for the site.
At RMA, the groundwater cleanup consists primarily of extracting groundwater and then treating it through groundwater treatment systems that are located both on and off site and at the boundary along Hwy. 2 and 96th Avenue (see map).
Due to the age of the existing boundary containment systems, the two plants must be replaced, as the systems are expected to require operation indefinitely to achieve cleanup objectives. Rather than constructing two new treatment plants, the existing plants are being replaced with a new single on-post Consolidated Groundwater Treatment Plant, which will be located along Hwy 2 (see map). This revision only affects the location of groundwater treatment and does not alter the requirement for continued operation of the boundary treatment systems. In addition, the RODs are being revised to include new treatment requirements for emerging contaminants identified after the RODs were signed.
These changes, while requiring an ESD, do not alter the overall hazardous waste management remedy selected in the ROD and are supported by federal, state, and local regulatory agencies.
Public Comments
This ESD is available for review online here. If you would prefer to review the document in person, you can do so at the RMA Joint Administrative Record and Document Facility(JARDF), which is located on the RMA in Building 129. Please call 303-289-0200 to schedule an appointment to visit the JARDF.
Community members are asked to submit their comments and questions by May 23, 2025, to kelli.n.schneider.ctr@army.mil.