Groundwater contamination from in situ leaching of uranium mining and groundw_ater restoration after decommissioned is an important environmental problem for uranium mining industry. Systematic monitoring and analysis for groundwater contamination of a de_commissioned in situ leaching wellfield was carried out. The in situ leaching production had not affected on the upper and lower aquifer which all indexes are within background of groundwater of this area and also accord with the ClassⅢgroundwater quality standards. The in situ leaching broug...