Determination of the alpha activity (natural and artificial) in soils and continental water in Peru

During the last decade, the Environmental Control Department of the Peruvian Institute of Nuclear Energy (IPEN) was addressed to the implementation of their Environmental Radiological Surveillance Programs in the country, using for this matter standard techniques of gamma spectrometry and radiochemical methods for the beta emitting radionuclides study in environmental components, which could be evaluated through gamma spectroscopy systems and proportional counters of low background. However, implementation of methods and systems for the level evaluation of the alpha emitting radionuclides, such as the descendants of the uranium and thorium, which play an important role concerning the annual dose that receive the population of a determined region, is still pending. For this reason, in August 31, 1998 a research agreement was signed between the International Atomic Energy Agency and the Environmental Control Department of IPEN in order to implement and study the alpha emitting radionuclides in samples of water and soil of our national territory. During the period between October 1998 and June 1999, a series of administrative and training management were carried out in order to have the equipment and necessary reagents to carry out determinations of the main alpha radionuclides. The delay was mainly due to the acquisition of the reagents which had to be imported since in the national market were not available. After this phase, the selected methodologies and the adjustment to our laboratory conditions were developed. Likewise, the alpha spectroscopy chain was assembled and the radiochemical treatments and preliminary instrumental lectures were initiated. This report shows the results and statistical evaluations obtained during this second phase of the Project, which have been useful to give the first step in the implementation of our analytical and instrumental assay methods for the determination of the alpha emitting radionuclides