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Milan Army Ammunition Plant


Aerial photo of Milan Ammunition site

Additional Resources
Site Summary Profile
EPA ID: TN0210020582
Location: Milan, Carroll, and Gibson Counties, TN
Lat/Long: 35.867780, -088.696110
Congressional District: 08
NPL Status: Proposed: 10/15/84; Final: 07/22/87
Affected Media: Ground water, Soil
Cleanup Status: Cleanup activities are underway
Human Exposure Under Control: Yes
Groundwater Migration Under Control: No
Sitewide Ready for Anticipated Use: No
Site Reuse/Redevelopment: Continued use - an active military facility is located on site
Site Manager: Carl Froede(froede.carl@epa.gov)

Current Status

The Milan Army Ammunition Plant (MLAAP) opened in 1941 for wartime munitions production. That work has recently moved to stand-by but could restart if needed. Today, MLAAP has two primary military missions: 1) Storage of munitions, and 2) Support for Army National Guard and Reserve units for staging equipment and training. Following many years of munitions production and due to the discovery of munitions-related contamination in soil and groundwater, EPA placed the site on the National Priorities List (NPL) in 1987. Working together EPA, the Tennessee Department of Environment and Conservation (TDEC), and the Army have investigated MLAAP soils and groundwater and have taken action to clean it up to protect workers, the local population of Milan and the environment. Site contaminationdoes not currently threaten people living and working at or near the site. By extracting and treating contaminated groundwater, capping and containing contaminated soil, conducting groundwater monitoring, and performing required Five-Year Reviews, EPA, TDEC and the Army continue to protect people and the environment from site contamination.

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Site Location and Background

The 22,540-acre site is an active military installation southeast of the Milan in western Tennessee. The installation includes many buildings and storage facilities. Rural residential and agricultural land borders the site to the north, south and east. Residential areas and the city of Milan border the site to the west and northwest. The installation began operating in 1941 to produce and store fuses, boosters, and ammunition. Uncontrolled wastewater disposal practices resulted in the contamination of soil and groundwater. In 1987, EPA listed the site on the NPL. With the need for military munitions being met at other plants across the country, MLAAP munitions assembly and production is in stand-by. National Guard and Reserve activities occur across the Post.

View site location map.

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Threats and Contaminants

Site investigations found contamination in groundwater and soil that could potentially harm people if exposed. Contamination resulted from wastewater handling practices. Primary contaminants of concern include 2,4,6-trinitrotoluene (TNT) and RDX, also known as cyclonite.

Ground water contamination affected the Memphis Sand Aquifer, the local public water supply. The Army worked with the City of Milan in the early 1990s to relocate the municipal drinking water well field. The Army also placed institutional controls on property adjacent to the Post that prohibits groundwater use in contaminated areas. Contamination in groundwater does not pose a threat to workers on the Post, nearby residences, or businesses.

The Army has capped and contained contaminated soil within the installationís boundaries.

Fencing and gates control access to the site.

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Investigation and Cleanup Responsibility / Oversight

The Army leads site investigation and cleanup activities, with oversight and technical support provided by EPA and TDEC.

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Site Cleanup Plan

Investigations and cleanup activities have focused on six areas, which EPA refers to as operable units, or OUs. These areas include: OU-1: O-Line Ponds groundwater; OU-2: O-Line Ponds soil; OU-3: Northern Boundary groundwater; OU-3/4: Northern Industrial Area soil; OU-4: Region 1 groundwater (Line X groundwater plume); and OU-5: Southern Study Area. These OUs cover large portions of the site and contain one or more specific areas of contamination. Cleanup activities have focused on contaminated soils and groundwater.

View OU location map.

The Army and EPA (with concurrence from TDEC) have issued a series of cleanup plans (Records of Decision, or ROD) for the OUs at the site.

Most recently, the Army and EPA issued an Explanation of Significant Differences (ESD) in 2012. The ESD addressed used munitions on the ground surface and buried beneath the ground surface. Following a site investigations, it was determined that these spent munitions were not a source of contamination. No cleanup was needed for the area.

In May 2014, the Army completed the installation of a perimeter fence and locked gate around the OU-5 area. This work was done to complete the hazard assessment for this site due to spent ordinance that is both on and immediately below the ground surface. Extensive land use controls will protect workers from exposure.

The EPA anticipates signing the final Site-Wide Groundwater Record of Decision before the end of 2014. This decision will expand the number of extraction wells to optimize the removal of the highest levels of contamination. These extraction wells will eventually (anticipated at 15 years) remove contamination to a level where natural degradation can return the water to drinking water safety standards (over an additional period of approximately 45 years). The groundwater cleanup action is anticipated to require a total of 60 years.

Summaries of site cleanup approaches are also available online in key site cleanup documents, including the RODs, ESD and Five-Year Reviews.

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Cleanup Progress

In the early 1990s, the Army worked with the City of Milan to relocate the municipal water supply wells affected by contaminated groundwater.

The Army completed construction of the pump-and-treat system for OU-1 in 1995. The system began operating at full capacity in 1998. The Army completed construction of a second pump-and-treat system in 1999 to address contamination at OU-3 and a third for OU-4 in 2002.

In 1995, the Army also completed an extension of the existing cap to address contamination at OU-2. Monitoring of the cap is ongoing. The Army removed soil from OU-3/4. Treatment is ongoing at an on-site soil composting facility.

Groundwater studies have been completed, a cleanup decision is anticipated in 2014, and full system operation is expected to begin before the end of 2014. All munitions contaminated groundwater will be in active remediation with the approximate completion date expected to occur around the year 2074.

The site’s third Five-Year Review, completed in 2010, found that the cleanups at OU-1, OU-2, OU-3 and OU-3/4 continue to protect people and the environment.

Summaries of cleanup activities are also available in Five-Year Reviews online.

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Enforcement Activities

In 1989, EPA, the Army and TDEC signed a Federal Facilities Agreement (FFA) for the site. The FFA helps make sure that the parties will fully investigate environmental impacts associated with past and present activities at the installation and undertake and complete appropriate cleanup actions. The FFA also establishes schedules and enforceable milestones for cleanup activities.

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Community Involvement

EPA has worked with the community and its state partner to develop a long-term cleanup plan for the site, reflecting the Agency’s commitment to safe, healthy communities and environmental protection. Community engagement and public outreach are core components of EPA program activities.

EPA has conducted a range of community involvement activities to solicit community input and to make sure the public remains informed about site activities throughout the cleanup process. Outreach efforts have included public notices and meetings. EPA staff also participates with TDEC and Army representatives on the local Remedial Activity Board. Its meetings are held in the city of Milan.

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Future Work

All six areas of munitions-related contamination are either capped, closed, or undergoing cleanup activities. Annual inspection reports, system operations reports, and status reports will keep EPA, the Army, and TDEC informed of ongoing activities. No other investigative or remedial activities are necessary.

EPA completed the last Five-Year Review in 2010 and plans to complete the next Five-Year Review in 2015.

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Additional Information

The Army maintains site documents and information at the locations listed below. Many of these documents are available for download from the MLAAP website. Exit Disclaimer EPA also posts site documents, when available, on EPAís CERCLIS Site Profile page. For documents not available on the website, please contact the Region 4 Freedom of Information Office.

Site Repository

Paper copies of site documents are located at:

Milan Army Ammunition Plant
2280 Highway 104 West
Milan, TN  38358

Electronic copies of the documents are located at:

Mildred G. Fields Memorial Library
1075-A East Van Hook Street
Milan, TN  38358

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