Uranium Concentrations In Groundwater Research Articles

Radium and uranium in phosphate fertilizers and their impact on the radioactivity of waters

The study of radioactivity in the phosphate fertilizers and waters of the Kanovci area was performed in order to determine the influence of the application of phosphate fertilizers on the radioactivity of waters. The activity of 226Ra, 228Ra, 235U and 238U was measured in different types of phosphate fertilizers and waters by means of γ-ray spectrometry. Surface water, water from drainage channels, shallow groundwater and deep groundwater samples were collected from the Kanovci agricultural and well field area in Eastern Slavonia, where phosphate fertilizers have been used for the past 15 years. 137Cs was also measured in water samples. The typical phosphate fertilizer used in the Kanovci area contains 75 Bq kg −1 of 226Ra, 9 Bq kg −1 of 228Ra, 52 Bq kg −1 of 235U and 1120 Bq kg −1 of 238U. The estimated annual deposition of uranium and radium in soils of the agricultural and well field area in Kanovci is: 4.5 Bq m −2 for 226Ra, 0.5 Bq m −2 for 228Ra, 3.1 Bq m −2 for 235U and 67 Bq m −2 for 238U. The greatest concentrations of both uranium isotopes are measured in water from drainage channels with a mean value of 120 Bq m −3 for 238U and 5.5 Bq m −3 for 235U. The concentrations of both radium isotopes generally increase with depth of water as distinct from uranium, whose concentrations in deep groundwater are much lower. The highest concentrations of 137Cs were measured in water from drainage channels; it was not detected in deep groundwater. The 238U/ 226Ra activity ratio (AR) is the highest in water from drainage channels and the Bosut River, while in deep groundwater the ratio is only 1.6. Results indicate that high uranium concentrations in surface water, shallow groundwater and water from drainage channels are caused by phosphate fertilizer application in agriculture on the Kanovci area.

In search of a characteristic signature for groundwater aquifers — A case study from Israel

The uranium isotopic and hydrogeochemical data of groundwaters in the Galilee, Betshean, Samaria and Beersheva regions of Israel, obtained from the published literature, have been re-interpreted according to new ideas gained from a study of uranium concentrations in groundwaters in Australia. It appears to be a general rule that the uranium concentration of natural waters is proportional to the HCO − 3 concentration in a way that is characteristic of individual aquifers. In the Israeli context, the major limestone and basaltic aquifers can be clearly distinguished, even to the extent of the mixing of waters from these two sources. The limitations of tracing groundwater bodies by the 234 U 238 U activity ratios vs. U-concentration plot are discussed and the need for interpreting uranium isotopic data in conjunction with hydrogeochemical data is demonstrated, which suggests that some of the earlier inferences made in the papers discussed, especially in regard to the Beersheva region could be reconsidered. The HCO − 3 vs. U correlation technique appears to be a good technique for tracing and delineating groundwater bodies in an oxidizing environment, irrespective of their size, residence time and conditions at the time of recharge.