ALPHA-SPECTROMETRIC MONITORING OF THE TERRITORY OF SILLAMAE METALLURGICAL PLANT (ESTONIA)

The composition and concentration of alpha-nuclides in the ground samp les from the area of Sillamae Concentration Plant were studied, includ ing samples taken from industrial zone and those taken at three differ ent depths in the depository of waste products of uranium and loparite ore recovery. The measurements were carried out by alpha-spectrometry in radiochemical and direct instrumental modes. The predominant activ ity in the tails depository is due to thorium-230, radium-226 with sho rt-lived decay products, and polonium-210. Analysis of ground samples taken from the territory of the Concentration Plant revealed areas sig nificantly contaminated with radionuclides. The data of alpha-spectrom etry suggest the genesis of contaminations, which are various mixtures of initial ores, enriched uranium concentrates, and tails of uranium recovery.