Kazatomprom and Uranium One, the international mining company of the Rosatom State Corporation, implemented a new method aimed at increasing of wells productivity efficiency in uranium in-situ leach mining. The method was developed in the framework of implementation of the plan of action for ISL process optimization and cost reduction. In particular, the new approach entails production wells repair and flow rates restoration adding ammonium bifluoride to conditioning agent.This process includes cleaning of porous space and creation of new channels in ore-bearing sediments for leaching solutions flows. It allows to increase operating wells flow rates, restore non-operating wells, and redouble the period wells’ overhaul cycle. Regular aquifer monitoring evidences a high level of environmental safety of this method. “During the wells’ operation, we usually observe a fall in their flow rate productivity, resulting from salts and clays build-up, and conventional methods for their restoration do not guarantee the desired results”, - notes Mikhail Pershin, a chief geotechnical engineer in Uranium One and one of the authors of the new method. – We suggested to apply for uranium ISL mining the technology of the wells’ flow rate increase used in the oil industry. As a result, we have a cost-effective technology with no alternative for ‘heavy’ wells flow rates recovery that should be redrilled in an alternative way”. The new approach was first tested at the Zarechnoye and Kharasan mines. Upon completion of the testing, the wells’ flow rate was recovered up to the initial values. Such positive experience with the new method was then used by most Kazatomprom, NAC JSC and Uranium One joint mines on an industrial scale.