Geofyzikální merení zvýseného obsahu uranu na opustených tezených lokalitách uranových rud na vybraných území Krkonosského národního parku/Geophysical measurement of the uranium in abandoned uranium mines on selected areas of the Krkonose National Park

The abandoned mined uranium mineralisations explorer deposits on localities Harrachov-Rýzoviste and Medvedín are situated right in the Krkonose National Park area (KRNAP). Especially the mobile hexavalent uranium U^sup 6+^ presents an environmental hazard. U^sup 6+^ might be easily adsorbed by colloids and with the mining water transported on the surface. Subsequent increasing pH-value with the surface waters mixing might contaminate the stream sediments, soils and water resources. It was verified that the gamma-ray spectrometry is suitable method for the detection of the U-anomalies in the field and in laboratory variation for determination of the U/eU ratio. At both localities the environment is not threatened, but mine work affects the natural radioactive elements mainly in the fine-grained sediments near the piles. [PUBLICATION ABSTRACT]