As part of the on-going stabilization action, the Emergency Response Section will be conducting an surface and subsurface soil asessment of the smelter. The target contaminants are heavy metals, radiological isotopes and VOCs. The area to be assessed is in the southeast corner of the smelter. Information collected during the IA, the stabilization action and through concerned citizens led to the investigation of this area. Information provided to OSC Wise indicated that the area may have been used as a disposal area. During the stabilization action, the START identified several areas of radioligical contamination. Gamma surveys of the area indicated residual gamma radiation in excess of 50x background (>1,000,000 cpm by NaI(Te) scintillator).
On June 29, 2007, OSC R. Wise accompanied by the START radiation support subcontractor visited the Halaco site to determine the extent of area to be assessed for radiological contamination. This activity included test trenches to determine the horizontal extent of contamination. Starting on June 29, 2007, ERRS contractor removed the surface concrete from the assessment area.
On May 31 and June 1, 2007, OSC Wise, the START and PST conducted a surface radiological survey of the area of concern. Preliminary survey data indicates the presence of residual radioactive contamination in excess of 2x background over approximately 2/3s of the assessment area. Numerous hot spots greater then 10 - 50 times background were discovered in the assessment area.
Starting June 4, 2007, surface and subsurface sampling of the target area will be conducted. The soil will be field screened for metals via XRF, gamma specroscopy for isotope identification and HAZMAT ID analysis for organic compounds. Based on the field analysis samples will be submitted to the lab for confirmation analysis. Splits will be provided to the PRP.
1. Horizontal and vertical extent of the radioactive and heavy metal contamination.
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