TRACERS FOR GROUND WATER INVESTIGATIONS

摘要: SUMMARY Tracers have been used since 1869 to establish hydraulic connections in the ground and determine velocity of ground-water flow. Some organic dyes, Sulforhodamine G Extra, Rhodamine WT under certain pH conditions also Uranine, seem be useful as tracers for investigating flow fractures channels (karst). As regards strong electrolytes, cations are mostly adsorbed porous media. studying such aquifers must therefore chosen from among anions metal complexes. Thanks rapid development analytical methods (atomic absorption, emission spectrography neutron activation analysis) it is possible today perform tracer tests using low concentrations The availability radioactive isotopes increased possibilities ground-water. Selective precise measurement very concentration radioisotopes can usually carried out directly field. Tritiated water said ideal behaves essentially same normal water. But tritium not easily detected field because its soft beta radiation. This fact has given rise an effort find a gamma-emitting isotope, gamma activity A great number tested. Among anions, iodide ion (NaI or KI containing I131) bromide (NH4Br Br82) most reliable. disadvantage that their half-lives too short tests. Two stable complexes: cobaltcyanide (K3CO(CN)6 Co60 Co58) chromium-EDTA-complex (Cr51-EDTA) more suitable successfully applied many investigations. new phase tracing application naturally-occurring tracers. These importance obtain general survey regional conditions, geographical origin, age balance.