Strontium-90 and cesium-137 in rain and dry fallout for domestic program from November 1983 to July 1984

Strontium-90 and cesium-137 in rain and dry fallout measured throughout Japan each month from November 1983 to July 1984 are given in mCi/km2. Sampling points are total of 22 from Sapporo (Hokkaido) to Nakagami-gun (Okinawa). Collection and pretreatment of samples, preparation of samples for analysis, separation of strontium-90 and cesium-137, determination of stable strontium, calcium and potassium, and counting are described. Rain and dry fallout was collected monthly on a sampling tray, approximately 5000 cm2 in area. The sample was then passed through a cation exchange column. After the radiochemical separation, the mounted precipitates were counted for activity using low background beta counters normally for 60 minutes. (Mori, K.)