Nammo Defense Systems Inc. Mesa, Arizona

Cleanup Activities

Site History

Talley Industries Inc. operated in Mesa from 1960 until the mid-1980’s. Talley specialized in the design, development and manufacture of ammunition and energetic material solutions for defense and commercial applications. In 1984, they became Talley Defense Systems, Inc. and continued operations until 2007. Nammo Group currently owns the original company and operates under NDS. The facility is located about 20 miles east-northeast of downtown Phoenix in the northern part of Mesa in Maricopa County, Arizona (See Figure 1).

Historical Release Areas

The environmental regulatory history of the facility includes two identified historical release areas: the former Water Bore-Out (WBO); and the former Thermal Treatment Unit (TTU). The TTU is currently being managed under the Order issued by the United States Environmental Protection Agency due to concerns related to the contamination migrating onto SRPMIC’s land.

Former TTU

The former TTU site is located within the current NDS facility approximately 1.25 miles north-northeast of the intersection of East Thomas Road and North Higley Road, Mesa Arizona.

Figure 1 Location map of the NDS facility

Contaminants of concern (COC) in this area include lead, perchlorate, volatile organic compounds (VOCs) and 1,4-dioxane. NDS has initiated multiple interim cleanup measures including source area soil removal, an in-situ biological injection pilot study, and the installation of a groundwater pump and treat system. The former TTU is no longer in use and a present day photo of the site, taken on 5/26/2021, can be seen below.

Former TTU area (current condition)

NDS has also established a network of ground water monitoring wells on and around the former TTU site to monitor the COCs as well as a network of extraction wells as part of the pump and treat system.

Work in progress for a well to monitor groundwater

Former WBO

The former WBO site occupies approximately 100 acres of land within the current NDS facility and is located northeast of the intersection of Greenfield Road and the Loop 202, Mesa Arizona. When in operation, the WBO facility used a high-pressure water jet to remove waste material from manufactured components. Presently, NDS is working under the regulatory oversight of the Arizona Department of Environmental Quality (ADEQ) and working within a Voluntary Remediation Program (VRP) to clean the WBO site. NDS has proactively initiated a pump and treat system using two extraction wells located on the site of the former WBO.

FBR groundwater treatment system

 A fluidized bed reactor (FBR) is used to treat the extracted water from the two wells. After treatment, the clean water is directed to the FBR ponds, where it is then allowed to re-enter the environment.