OFF-POST CONTAMINATION

 

SITE DESCRIPTION

Historical discharges of explosive-contaminated wastewater has resulted in surface water and groundwater contamination off-post, mainly the Brush Creek watershed.

In 1993, off-post contamination of private drinking water wells with explosives (RDX and 2,6 DNT) was confirmed. The IAAAP contracted to connect residents in the contaminated area to the public water supply. This Remedial Action was designed to eliminate the pathway of future exposures to contaminated drinking water and was completed in the fall of 1994. IAAAP is investigating groundwater contamination both on and off-post. The off-post efforts were accelerated in 1998 due to increased stakeholder interest.

High levels (up to 150ug/L) of RDX were detected in the Brush Creek watershed approximately 2 miles off-post.

In 2001 IAAAP provided connection to Rathbun Regional Water to 34 homeowners who declined in 1993. The total number of homes connected to the Rathbun Regional Water supply is 188.

In 2003, during annual groundwater sampling, groundwater was analyzed for radionuclides by FUSRAP.  Only naturally occurring isotopes were detected.

The FS and proposed plan were completed in 2004. The preferred alternative is enhanced bioremediation.

The ROD for off-post groundwater was signed in 2005.

Phase progress will be tracked for this PBC Site, but funding requirements will be tracked under Site PBC at Iowa.  Post PBC costs will be tracked under Site IAAP-020.

CLEANUP STRATEGY

The implementation of the OU-3 ROD for Off-Post Groundwater will continue.  Enhanced degradation will continue until RDX in groundwater is below 50 ppb throughout the plume.  The remedy will continue with monitored natural attenuation, and institutional and engineering controls until acceptable human health risks are achieved.

STATUS

RRSE RATING: High

CONTAMINANTS: Explosives

MEDIA OF CONCERN: Groundwater, Surface Water

COMPLETED IRP PHASE: PA/SI, RI/FS, IRA, RD 

CURRENT IRP PHASE: RA(C)

FUTURE IRP PHASE: RA(O), LTM