Радионуклидный состав природных вод Новосибирской городской агломерации

Abstract

Results of the studies of 238U, 232Th, 226Ra and 222Rn distribution in the natural waters of the Novosibirsk Area are presented. Dominating in chemical composition are HCO3 Mg-Ca, HCO3 Na-Mg-Ca и SO4 -HCO3 Na-Mg-Ca waters with TDS 127 to 1568 mg/dm3 , and silicon content 0.14 to 17.63 mg/dm3 . These waters are characterized by pH from neutral to alkaline (6.6-9.5). The values of Eh vary from reductive -164.2 mV to oxidative +509.5 mV with dissolved oxygen content O2dissolved within the range of 0.16-20.78 mg/dm3 . The concentrations of natural radionuclides are (mg/dm3): 238U (2.70•10-6 - 6.5), 232Th (1.86•10-7 - 2.16•10-3), 226Ra (2.46•10-10 - 3.7•10-7). The activity of radon (222Rn) varies within a broad range from 1 to 43764 Bq/dm3 . The 232Th/238U ratio varies from 2.63•10-5 to 2.96. The nature of radioactivity of the studied waters is due mainly to uranium because the waters are characterized by the oxidative parameters of the geochemical medium, with maximum uranium concentrations in the scattering halo of the Prigorodnoe deposi.