LINE 5A & 5B AMMO ASSEMBLY

 

SITE DESCRIPTION 

The IRP site consists of the contamination from past munitions production. Any contamination from current activities will be addressed under compliance (non-ER,A funding). In the past, both lines were component lines for pelletizing and assembly of explosive components. A testing platform and a firing pit are located within the site boundary. Principal explosives used at these lines were TNT, RDX and Tetryl.

Lines 5A and 5B were booster and grenade lines situated in the north-central portion of the installation. Line 5A is about 33 acres and Line 5B is 41 acres. Both lines were constructed in 1941 and operated from 1942 to 1945. Production resumed in 1949 during the Korean War and intensified in 1961 during the Vietnam War.

Line 5A is currently in a caretaker status; there are no plans to activate this line in the future. Line 5A is under the Industrial Preparedness Plan (IPP). Line 5B is being rented by Advanced Environmental Technology (AET) for destructive disposal of ammunition.

The PA/SI was completed in 1991, and an initial RI was completed in May 1996. Approximately 6,000cy of contaminated soil were removed in FY00-01. During the removal action Building 600-84 and the Central Test Area were discovered as potential areas of concern. AET tested the soil at Building 600-84 and found no contamination. RDX and TNT in concentrations of up to 46 ppb have been found in the groundwater in a shallow localized plume within 30 feet of the ground surface. The presence of UXO in and around the Central Test Area will adversely affect cost and schedule of any remedial action. Also, the area considered to be potentially contaminated with explosives and metals is now thought to be as much as 17 acres. This area will be incorporated into a new AEDB-R site IAAP-047, Central Test Area.

A revised draft OU3 RI/FS was submitted to EPA for review in April 2008 to address groundwater; the recommendation for groundwater at Line 5A is institutional controls, monitored natural attenuation, and long term monitoring and the recommendation for Line 5B is either “No Further Action” or “institutional controls, monitored natural attenuation, and long term monitoring” depending on the selected risk level.