Pu-241 in samples of forest soil from Poland

• Published in: Applied radiation and isotopes Vol. 51; no. 4; pp. 435 - 447
• Main Authors: Mietelski, Jerzy W, Dorda, Jerzy, Wąs, Bogdan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-10-1999
• Subjects: Chernobyl; Fallout; Forest soil; formula omitted; LSC; Plutonium - analysis; Poland; Power Plants; Predictive Value of Tests; Radioactive Fallout; Radioactive Hazard Release; Soil Pollutants, Radioactive - analysis; Spectrum Analysis - methods; Trees; Ukraine; Poland; Ukraine; 241 Am; Chernobyl; Forest soil; 241 Pu; Fallout; LSC
• ISSN: 0969-8043; 1872-9800
• DOI: 10.1016/S0969-8043(99)00055-X

241
Pu
activity measurements in coniferous forest soil samples from Poland are presented. The results were obtained in two ways: by alpha spectrometric remeasurements of the plutonium sources 3–4 years after their preparation (i.e. by the
241
Am
ingrowth) and by direct measurements of
241
Pu
using liquid scintillation (LS) spectrometry. Both methods gave consistent results. The maximum observed activity concentration obtained by the
241
Am
ingrowth was (254±43) Bq/kg, and by direct measurements it was (284±31) Bq/kg (the same sample, activities calculated for May 1, 1986). Enhanced levels of
241
Pu
were observed in all samples from the farthest north-eastern Poland. The estimated
241
Pu
maximum deposition from Chernobyl fallout in this area (sum of deposition for two examined layers of one site) was (1.025±0.110) kBq/m
2. This will result after 70 years in an additional
241
Am
activity of about (30.1±3.2) Bq/m
2. The average ratio for
241
Pu
to total
238,239,240
Pu
was of the order of 25. The obtained average Chernobyl ratios for
241
Pu
to
239,240
Pu
were about 86, and those for
241
Pu
to
238,239,240
Pu
were 56.