Fact Sheet
Investigative Activities
January 2008

Clean Close Out Activities at Building 4343

Introduction

This fact sheet describes the completed action for cadmium-contaminated soil at Building 4343 – Former Cadmium Plating Facility at Radford Army Ammunition Plant (RFAAP). The selected alternative was selected in accordance with the Resource Conservation and Recovery Act of 1976 (RCRA), the Hazardous and Solid Waste Amendments of 1984 (HSWA), the RFAAP Resource Conservation and Recovery Act (RCRA) Permit requirements (USEPA, 2000) (EPA ID No. VA1210020730), and the Final RCRA Corrective Action Plan (USEPA, 1994), as applicable.

Background

The Building 4343 parcel is located in the west central portion of the Horseshoe Area and was established in 1956. Cadmium plating activities were conducted at Building 4343 in support of the NIKE missile program. Treated process water was discharged to an unlined ditch north of the site. The RFAAP RCRA Corrective Action Permit, signed in September 2000, identified Building 4343 as an Area of Concern (AOC) that had the potential to pose a threat, or potential threat, to human health and the environment. The Permit required that a sampling strategy be developed to complete the delineation and characterization of the site. RCRA Facility Investigation (RFI) field efforts were conducted in 1999 and 2002. Data indicated that metals (mainly cadmium) had contaminated soil around Building 4343 and in the process water discharge ditch and alluvial fan. The contamination was mostly confined to the top two feet of soil. Two sumps, related to Building 4343, were identified as having elevated concentrations of metals. Since one of these sumps was located inside Building 4343 there was the potential for contaminated soil underneath the building. Human Health and Screening Level Ecological risk assessments indicated there was elevated risk at the site and remedial measures were necessary to ensure the protection of human health and the environment.

A Corrective Measures Study (CMS) was completed to evaluate remedial measures. The selected remedial measure was “Excavation of Soil for Clean Close Out, Off-site Disposal, Removal of Sumps, and Removal of Building 4343” because it was implementable and provided a greater level of protection to human health and the environment than the other alternatives evaluated in the CMS. This alternative facilitated clean close out, was cost effective, and was protective of groundwater. By achieving clean close out, these corrective measures accomplish the Army’s IRP goal of cleaning up the site and restoring it for beneficial use.

Remedial Action

Prior to implementation of the alternative, an Interim Measures Work Plan that provided specific details on the field aspect of the remediation was prepared and submitted to the EPA and VDEQ.  Once the work plan was approved by the regulatory agencies, the remediation effort was scheduled for the summer of 2006.

The first step was the delineation of soil containing cadmium above the Residential Remedial Goal (RG) and characterization of the wastes (soil, building debris and sump debris) for disposal.  Twenty three surface soil samples and 24 subsurface soil samples were collected from the perimeter of cadmium containing soil area prior to beginning the excavation.  For the waste characterization, samples were collected from the soil; the building debris; and the sump material.  Results indicated that the soil was hazardous, while the building and sump debris was non-hazardous.

Following delineation, cadmium containing soil was excavated using a 20-ton track mounted excavator and direct loaded into dump trucks for disposal in an EPA/VDEQ /Army approved hazardous waste landfill.  Approximately 715 tons of soil were removed during the course of the remediation.

Prior to the demolition of Building 4343, asbestos-containing ceiling tiles and pipe insulation were removed and segregated.  The asbestos containing material was removed (and disposed of) by a Virginia licensed Asbestos Abatement Contractor under the supervision of a Virginia licensed Asbestos Project Monitor.  After removal of the asbestos, the building was demolished and the two sumps were removed.  Approximately 360 tons of building/sump debris were shipped offsite and disposed of as non-hazardous waste.  Six tons of metal debris was segregated from the building debris and sent separately to a metal recycling facility.

Confirmation samples were collected from the perimeter of the excavation to ensure that soil with cadmium concentrations greater than the remedial goal (RG) had been removed.  If a sample result was greater than the RG, additional soil was excavated and additional confirmation samples were collected until confirmation results were less than the RG.  Samples were also collected from beneath the footprint of the building at this time.  Results from these samples indicated that approximately 2 ft of soil from beneath the building needed to be removed.  As with the main excavation, soil removal and confirmation sampling were conducted iteratively until sample results demonstrated that soil with cadmium above the RG had been removed.  A total of 57 confirmation samples were collected at the site.

Once confirmation sampling indicated that soil removal was completed, the land surface was restored to its natural grade by bringing in clean fill to backfill the excavation.  The top six inches were backfilled with topsoil so that the area would re-vegetate.  The excavation footprint was hydroseeded and covered with straw to prevent erosion.  The site was inspected one month after completion and six months after completion to ensure that no erosion occurred and that the grass was growing.

After field activities relating to the remediation of the site were complete, an Interim Measures Completion Report was prepared and submitted to the EPA and VDEQ.  This report summarized the remedial actions performed at the Building 4343 study site and contains sample results; an excavation map; a photo log of the activities; and disposal information for the soil and building debris.  Copies of the Building 4343 documents are located in the RFAAP information repository and can also be found on the Radford IRP website at the following links.

Building 4343 RFI/CMS Report, Final. February 2004

Building 4343 Interim Measures Work Plan, Final.  August 2006

Building 4343 Interim Measures Completion Report, Final.  April 2007