In-situ Alpha Detector for Wet Soil

Abstract

In some areas of nuclear site, the soil has been found to be contaminated with alpha sources. In the field, surveyors have been using a square-head alpha counter to scan the soil to determine the contamination. However, this technique only works for dry soil. If the soil is wet, the alpha radiation is almost completely attenuated by the water film. If it has rained, or the soil is wet from dew, the current field detection technique doesn't work since the alpha counter can't detect the radiation. The work we have performed is to develop an instrument which can provide in-situ alpha radiation measurement for wet soil.