CORNHUSKER ARMY AMMUNITION PLANT NEBRASKA EPA ID# NE2213820234 EPA Region 7 City: 6 miles west of Grand Island County: Hall County Other Names: 12/05/2005 SITE DESCRIPTION The 19-square mile Cornhusker Army Ammunition Plant is a former U.S. Army Armament, Munitions, and Chemical Command facility. On standby status since 1973, the operation leases land for agriculture, grazing, and wildlife management activities. The plant was built in 1942 to produce munitions and provide support functions during World War II. It has been in and out of production over the years. The plant consists of five main components: five major production areas where munitions were loaded, assembled, and packed; a fertilizer manufacturer; two major storage facilities; a sanitary landfill; and a burning ground where materials contaminated with explosives were ignited. When the plant was active, staff disposed of wastewater contaminated with explosives into 56 earthen surface impoundments, which were located near the five production areas. Dried solids from the bottom of the pits periodically were scraped and ignited at the burning ground. Releases from the surface impoundments have contaminated approximately 500 private wells. Activities at the site currently are limited to maintenance and leasing operations. The Omaha District Corps of Engineers is in the process of selling the property. Polluted groundwater has migrated off the site and has been detected as far as 7 miles beyond the plant's border. The area affected by groundwater contamination is mostly suburban, and residents now rely on public water supply for drinking water. Approximately 3,000 people live within 1 mile, and 27,000 live within 3 miles of the site. Groundwater also is used for farmland irrigation and for watering livestock. Site Responsibility: This site is being addressed through Federal actions. NPL LISTING HISTORY Proposed Date: 10/15/84 Final Date: 07/22/87 ------- Deleted Date: THREATS AND CONTAMINANTS Groundwater both on and off the site is contaminated with various explosives. Soils are contaminated with various explosives and heavy metals such as lead, chromium, and cadmium. Human and livestock health may be adversely affected by drinking contaminated groundwater or through direct contact with contaminated soil. The provision of bottled water and alternate water supplies has reduced the potential of exposure to hazardous substances in the drinking water. CLEANUP APPROACH Response Action Status The Army provided bottled water to the 250 homes with contaminated wells until residences could be hooked up to the city's water system. In 1986, the municipal water system was extended to 800 residences in Grand Island. In 1987, the Army started an incineration program to treat the contaminated soil in the 56 surface impoundments. Workers excavated the soil and then incinerated it to destroy the contaminants. The excavated pits were backfilled with off-site sand and gravel, and the ash from the incinerator was landfilled on site. The Army had burned 40,000 tons of soil, when the State-monitored operation ended in 1988. In 1991 and 1992, the Army provided bottled water to additional homes with contaminated wells until residences were hooked up to the City's water system. In addition, the Army built a protective barrier around unexploded ordinance at the burning ground in 1993. Groundwater: In 1990, an investigation by the Department of the Army identified several areas of potential contamination. The Army investigated the plume of groundwater that moved off site to determine the types and levels of contaminants present and the extent of threat to human health and the environment. The Army submitted a draft report of the investigation in early 1993, but the EPA, the Army, and the State of Nebraska agreed that additional work would be necessary due to data gaps. This work involved dividing the site into smaller areas to facilitate the additional field work required. A study of ways to prevent further contaminant migration of the groundwater contaminated with explosives was completed in 1994. An interim cleanup remedy involving groundwater containment was selected in 1994 that called for the construction of a groundwater pump and treat system. The system is operational and an additional onsite well was constructed in the summer of 1999. As a result of the operation of this seventh well, no contaminated ------- groundwater leaves the site. Description: Site Facts: Cornhusker Army Ammunition Plant is participating in the Installation Restoration Program, a specially funded program established by the Department of Defense (DoD) in 1978 to identify, investigate, and control migration of hazardous contaminants at military and other DoD facilities. An Interagency Agreement between the EPA, Nebraska Department of Environmental Control, and the DoD was signed in 1990. Under this Agreement, the Army is investigating and cleaning up the site. ENVIRONMENTAL PROGRESS The extension of the municipal water supply to over 800 residences and the provision of bottled water to additional homes has reduced the potential of exposure to hazardous substances in the drinking water. The excavation and incineration of contaminated soil has resulted in elimination of a primary source of contaminants and reduced other pathways of contamination at the Cornhusker Army Ammunition Plant site. These actions protect the public health and the environment The construction of the onsite groundwater extraction system began the summer 1997 and was completed a year later. The system extracts contaminated groundwater at seven onsite wells. After passing through a carbon filtration system, the drinking water quality groundwater discharges to ditchs on the site. The offsite contamination plume continues to shrink as measured by the groundwater monitoring study. The extraction wells are capturing all of the plume before it leaves the site. A ROD Amendment was signed in September 2001, to change the offsite plume treatment to natural attenuation. Groundwater models show that the off site plume will be below cleanup levels in 3-5 years and on site plume in 10 to 15 years.. Following the annual Installation Action Plan meeting in July of 2005, the Army revised the Federal Facility Agreement schedule in August 2005, and the Army has awarded $3.5 million in contracts to develop installation wide work plans for groundwater monitoring, sampling under former Load lines 1 & 2 slabs and asbestos removal. Groundwater monitoring around Tracts 19, 20 and 21 will focus on freon releases previously identified, which could be indicative of additional buried gravel mines. Additional characterization of sites will be included in future work. Phase II work under the contracts will involve site specific work from data generated during the the Phase I investigations ------- COMMUNITY INVOLVEMENT The site has an active County Reuse Committee, Hall County, which has been leading the efforts to find suitable future uses for property that has been or will be transferred out of Army ownership. The US Army Corps of Engineers web site, where site fact sheets can be viewed, can be accessed at: http://w3.nwo.usace.Army.mil/html/pm-8/homefeb.htm ------- SITE REPOSITORY ra a Grand Island Public Library, 211 North Washington Street, Grand Island, NE 68802 Cornhusker Army Ammunition Plant, 102 North 60th Road, Grand Island, NE 68803 Superfund Records Center 901 N. 5th St. Kansas City, KS 66101 Mail Stop SUPR (913)551-4038 REGIONAL CONTACTS SITE MANAGER: E-MAIL ADDRESS: PHONE NUMBER: COMMUNITY INVOLVEMENT COORDINATOR: PHONE NUMBER: E-MAIL ADDRESS: STATE CONTACT: PHONE NUMBER: Bryant Burnett burnett.bryant@epa.gov. (913)551-7742 Ed Southwick, NDEH (402) 471-2988 MISCELLANEOUS INFORMATION STATE: NE 073W CONGRESSIONAL DISTRICT: 03 EPA ORGANIZATION: SFD-SUPR/FFSE MODIFICATIONS Created by: Karla Created Date: 10/17/97 02:20 PM Asb erry/SUPRFUND/R7/U S EPA/US Last Modified by: Bryant Last Modified Date: 12/05/2005 09:56 AM Burnett/SUPR/R7/USEPA/U S ------- ------- |