Aerial radiological survey of the Point Beach Nuclear Power Plant and surrounding area

摘要

Radioactivity surrounding the Point Beach Nuclear Power Plant was measured using aerial radiological surveying techniques. The purpose of this survey was to document exposure rates and identify radiation sources within the survey area. The surveyed area included a 25-square-mile (65-square-kilometer) area, which encompasses the plant site. Data were acquired using an airborne detection system that employed sodium iodide, thallium-activated detectors. Exposure rates at 1 meter above ground level were computed from these data and plotted on a U.S. Geological Survey topographic map of the survey area. Several ground-based exposure-rate measurements were made for comparison with the aerial survey results. Exposure rates in areas surrounding the plant site varied (a) from 10-14 microroentgens per hour ((mu)R/h) in cultivated fields, (b) from 8-10 (mu)R/h in adjacent areas and along roadways, and (c) below 6 (mu)R/h over waterways and wetland areas. Man-made radiation (102-202 (mu)R/h) was found at the plant site; cobalt-60 was the primary source of activity found at the Point Beach site. No other detectable sources of man-made radioactivity were found. The exposure rates measured during this survey agreed well with those measured during the 1970 survey even though the survey methodology and parameters were significantly different.