Method for identifying areas of virgin soils using a portable gamma-spectrometer-dosimeter

Abstract

The dose rate of gamma radiation in air at a height of 1 m above the surface of virgin (undisturbed) soil is the starting point in the basic model that is used to estimate the dose of external radiation to the population living in areas contaminated due to the Chernobyl accident. Today, i.e. more than 30 years after the fallout, the finding of truly virgin lands is a rather difficult task, because many meadows were repeatedly plowed and/or rehabilitated after the accident. The purpose of this study was to develop a quantitative criterion for the detection of virgin soil areas using a portable gamma-ray spectrometer-dosimeter. To achieve this, we have conducted a statistical analysis of published and new data on the use of in situ gamma-ray spectrometry in radioactively contaminated territories of the Bryansk region of Russia and the Gomel region of Belarus in 2015–2018. The sample contains results of decoding 60 gamma spectra recorded at a height of 1 m above the ground in virgin meadows, cultivated lands and forests. Based on the performed analysis, a quantitative dosimetric criterion is proposed for in situ identification of virgin soils using a portable gamma-spectrometer-dosimeter. The article presents an algorithm for searching a virgin plot.

Keywords

• virgin soil
• ¹³⁷cs
• ambient dose equivalent rate
• build-up factor
• in situ