LINE 6 AMMO PRODUCTION (DETONATOR)
SITE DESCRIPTION
The IRP site consists of the contamination from past munitions production. Any contamination from current or future activities will be addressed under compliance (non-ER,A funding).
Line 6 is a detonator production area encompassing 30 acres and located in the center of the installation. Constructed in 1941 and operated until 1981, this line is currently inactive. Line 6 consists of 34 buildings for the production, storage, and shipping of detonators, relays, and hand grenade fuses.
The primary waste stream was related to the production of detonators and included lead azide, lead styphnate, tetracene, RDX, barium nitrate and mercury fulminate. Treatment of black powder was performed at Line 6 as a RCRA permitted unit. This unit underwent RCRA closure in 1995 and will no longer be maintained or used by the Army (modified caretaker status). As part of the RCRA closure, 800cy of contaminated soil were removed in 1994.
The PA/SI was completed in 1991, and an initial RI was completed in May 1996. The Interim ROD requires the removal of approximately 445cy of contaminated (metals) soil that was not addressed under the RCRA closure. This soil will be taken to the Inert Disposal Area (IAAP-020) and sorted by contaminant level and type. The principal concern at this site is the potential for surface runoff to migrate to nearby streams, which in turn recharge groundwater off post. Groundwater at the site shows no significant contamination. During the historical site assessment, it was determined there was a potential UXO concern at this site.
A Geophysical Density Survey for Munitions and Explosives of Concern (MEC) was performed at Line 6 in the fall of 2004 by MKM. The MEC density survey was performed using an electromagnetic metal detector to a depth of 4 ft. below ground surface. MEC avoidance procedures should be used during any sampling and clearance is required prior to any large scale soil removal.
The Army has determined that the facilities at this Line are excess and will pursue Non-ER,A funding for building demolition and debris removal, which is listed as an option in the PBC. Additional evaluation of soil beneath the slabs will be required after the demolition.
CLEANUP STRATEGY
This site is included in the PBC awarded in 2004.
The soil contaminated with explosives and/or metals at this site have been successfully completed by excavation, in accordance with the RAOs established in the final ROD to protect human health and the environment. Any contaminated soil under the infrastructures of IAAAP, and therefore inaccessible, was left in place. Once confirmation samples determined that all accessible contaminated soil had been removed, each excavation was backfilled with clean soil to the original grade, compacted, and then reclaimed to original conditions. All excavated soil was transported to Trench 6 in the IDA for later treatment. A total of 56 cy of contaminated soil was removed from Line 6 in the Fall of 2006.
This site is considered Response Complete (RC) as of September 2007 as documented in the Remedial Action Report for OU1 Soils Phase 5, 7, and 8 Sites and Installation Wide Ecological Evaluation.
A revised draft OU3 RI/FS was submitted to EPA for review in April 2008 to address groundwater; the recommendation for groundwater is No Further Action.
MEC and MC will be addressed under the MMRP.