Arizona Army National Guard Camp Navajo

Arizona Army National Guard Camp Navajo: Page 2 of 2

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The installation operated as a reserve supply depot for the receipt, shipping, storage, surveillance, minor maintenance and demilitarization of ammunition/explosives and assigned commodities. The OB/OD Area was formerly used for demilitarization and land disposal of obsolete and unserviceable conventional ammunition, explosives, and limited chemical warfare agents.

Operational control of the base was transferred in 1982 under an intra-State support agreement from the Secretary of the ARNG. After the transfer, the missions for the ARNG were training, continuing depot activities and facilities maintenance. In 1993, operational control was again transferred under the Base Realignment and Closure Act of 1988 (BRAC) to the ARNG, and the name was changed to Camp Navajo. The installation continued as a major training site, and also performing depot-level storage service for the Department of Defense (DoD), other government, and civilian entities. As a condition of the transfer, the Army maintained responsibility for cleanup activities at the facility. Demilitarization activities ceased in 1994 in connection with the closure of Camp Navajo under BRAC.

In 2002, a Stakeholder’s Advisory Group (SAG) was formed to assist the ARNG with stakeholder concerns. The SAG consisted of members from agencies such as the U.S. Fish and Wildlife Service, ADEQ, the Arizona Game and Fish Department, the U.S. Forest Service, the ARNG, as well as three community members. The SAG completed its task by 2011 and no longer meets.

Camp Navajo did not qualify for inclusion on the U.S. Environmental Protection Agency's (EPA) National Priorities List, but regulatory oversight is provided by ADEQ under the DoD’s Installation Restoration Program (IRP) and Resource Conservation and Recovery Act (RCRA). 

Over the years several studies, investigations and removal actions have occurred at Camp Navajo, including numerous munitions-related sites, resulting in either no further response action, long-term management (LTM), land use controls (LUCs) or post-closure care (PCC). Currently there are five sites that were placed into LTM under the IRP since at least 2005, and subsequently 2015 and one PCC site under RCRA. The IRP sites consists of Navajo Army Depot (NAAD)-01, NAAD-11B, NAAD-20, NAAD-40, and NAAD-43. The PCC site includes the former OB/OD Area designated as the Munitions Response Work Area (MRWA)-02, formerly identified as NAAD-02.

As part of the IRP, five-year reports are conducted to ensure the selected remedies remain protective to human health and the environment. The last five-year performance was completed in October 2015. The next Five-Year Review will be completed in 2020 with a kick of meeting in March.  

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Five IRP sites continue to be monitored and reported annually for groundwater and LUCs within the installation. Groundwater monitoring results from NAAD-11B will be used to support characterization and closure of this site. Results from groundwater monitoring at NAAD-40 will be used for ongoing compliance monitoring. No groundwater samples are collected at NAAD-01, NAAD-20, or NAAD-43. The LTM activities required at these sites consist of inspections and maintenance with respect to specific criteria used to determine compliance of the implemented remedies (i.e. LUCs). The Five Year Review Report is expected for ADEQ review and comments in late 2020. The sampling activities began at NAAD-43 in May 2020 to determine the sites closure potential.

A PA/SI Work Plan was approved in April 2020 for three sites identified as NAAD-25, NAAD-26, and NAAD-39 under the hazardous waste post-closure permit. It was determined to investigate these sites under CERCLA and sampling activities began in May 2020.

NGB has plans to investigate the installation for per- and polyfluoroalkyl substances (PFAS).

Munitions and munitions constituents remain in place at MRWA-02. A hazardous waste post-closure permit was issued for MRWA-02 on January 27, 2017. The permit requires long-term maintenance activities including inspections and groundwater monitoring.

This Federal Department of Defense (DOD) Site is also listed as hazardous waste site on My Community | View Hazardous Waste Sites Page >