The relevance of the problem of increasing the efficiency of using the metallic mineral resources extracted from the bowels on the earth's surface is explained by the increasing demand of industrial metals to meet the vital queries of the human. 
The aim of the study is to develop environment-friendly and resource-saving technologies of extracting metals from sub-standard raw materials in underground mining of metallic mineral deposits. 
Research methodology includes a set of methods that collectively define the feasibility of involvement in production of non-conforming metallic resources using hydrometallurgical technologies and increasing the extraction of metals compared to traditional washing technology. The main method is semi-experimental leaching of uranium ore in the pile. 
The results of the research allow us to optimize the organization of work on leaching metals by controlling the process parameters at all stages of leaching of off-grade mineral raw materials in the stacks with a differentiated assessment of the influence of major processes on leaching rates. The paper introduces the data on consumption of reagents and materials, extraction of metals into solution and out of solution and neutralization of the mother liquor. It is shown that leaching in the pile does not radically improve performance of traditional methods of extraction of metals, but only reduces the metal content in the secondary tails. The paper identifies the deficiencies of existing methods of assessing the impact of mining on the environment.
The conclusion from the results of the study is that leaching in a stack does not solve the problem of non-waste, essentially increasing the exposure time of chemically hazardous products to living matter.