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Chocolate Mountain Aerial Gunnery Range

Environmental Restoration Program Public Website

This website provides background information on the Department of the Navy’s (Navy) Environmental Restoration Program (ERP) site at Chocolate Mountain Aerial Gunnery Range (CMAGR). The overarching goal of the Navy’s ERP is to protect human health and the environment from past hazardous waste practices and releases at Navy Installation Restoration Program (IRP), Munition Response Program (MRP), and Underground Storage Tank (UST) sites. The Navy’s ERP at CMAGR is managed by the Naval Facilities Engineering Systems Command Southwest in San Diego, California.

There is currently one MRP site managed under the Navy’s ERP at CMAGR. Seven additional IRP sites have been managed in the past under the Navy’s ERP but are closed and require no further action. One IRP site was removed from the program since the site is actively used.

The Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980 created the legal mechanism for the cleaning up abandoned or uncontrolled hazardous waste sites and was adopted by the Department of Defense (DoD) as a model for environmental cleanups by the military. It is the guiding process for environmental remediation efforts at CMAGR sites.

The Superfund Amendments and Reauthorization Act (SARA) amended the CERCLA legislation in 1986. Among other changes, SARA established the Defense Environmental Restoration Program (DERP). The Secretary of Defense provides oversight of the DERP and has delegated responsibility the DERP’s implementation and the DoD’s lead agency status to individual military departments. The DERP cleans up hazardous substances, pollutants, contaminants, and military munitions remaining from past activities at active military installations, installations undergoing base realignment and closure, and formerly used defense sites. Because the DERP has a substantially larger scope than CERCLA, certain petroleum releases may be remediated using DERP funds, sites do not need to be on the National Priorities List (NPL) to be managed using DERP funds.

The Navy the lead federal agency working with the California Department of Toxic Substances Control, the Regional Water Quality Control Board, United States Fish and Wildlife Services, and Bureau of Land Management (BLM) to collect and evaluate environmental data addressing issues related to ERP site.

Chocolate Mountain Aerial Gunnery Range History

CMAGR is approximately 460,000 acres approximately 100 miles east-northeast of San Diego and 30 miles northeast of El Centro, in Riverside and Imperial counties, California. The nearest communities are Niland and Slab City to the south, and Mecca to the west. The range is situated east of the Salton Sea and follows a similar northwest to southeast alignment and shape.

The CMAGR was initially established during World War II (WWII) for military aviation training. Land combat training at the CMAGR also began during WWII with the opening of a U.S. Marine Corps (USMC) artillery school. Use of the range for training Naval Special Warfare forces dates from 1966 and is oriented toward individual fighting skills and small team tactics. In addition to CMAGR-specific training, WWII training and stationing of troops associated with General Patton’s Desert Training Center was also conducted throughout the Sonoran and Mojave Deserts across a wider area than the CMAGR. Military training following WWII appears to have been focused inside the CMAGR boundary. Since the late 1970s, training of USMC land forces has typically emphasized integration with USMC air forces but has also included training of infantry combat teams.

The BLM and Navy lands in the CMAGR are generally interspersed in a checkerboard pattern of one square-mile sections but are used collectively and in common to support the air combat training missions and other defense activities that occur at the range. While the range supports several military entities, the USMC is the primary user of this range. Local command for military operation and administration of the CMAGR has been delegated by the Secretary of the Navy to the Commanding Officer, Marine Corps Air Station Yuma, Arizona.

Environmental Restoration Program Background

The purpose of the Navy’s ERP is to reduce the risk to human health and the environment from past contamination by identifying IRP and MRP sites and moving them through the CERCLA process.

Environmental investigations and restoration activities at CMAGR have been ongoing since 1992, and have investigated seven IRP sites. IRP Site 2 was removed from the IRP in 2003 since it was located on an active firing range and contamination was a result of current use. All other IRP sites have been closed since 2006 with no further action required.

As mandated by the National Defense Authorization Act of Fiscal Year 2002, the DoD developed the MRP to address military munitions under the DERP. This program was initiated specifically to address unexploded ordnance, discarded military munitions, and associated chemical residues referred to as munitions constituents on current and former military installations. The CMAGR has one active MRP site, identified as UXO 1 or Bradshaw Trail.

CLICK HERE for information on the Navy’s ERP.

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