The Chertovo Koryto deposit is located in the Lena gold province, in the Irkutsk region of eastern Siberia. The deposit is located in a remote area, approximately 200km northeast of Bodaybo and 170km north of Polyus Gold's Verninskoye asset. Between 2003 and 2007 ore was mined from both placer deposits and the open pit, with the ore processed at a pilot plant on a seasonal basis. In late-2018 Polyus commenced the pre-feasibility work which will encompass open pit modelling, mine scheduling, engineering of the crushing and grinding circuits, assessing the different process routes. It is proposed that the project will be developed as an open pit with the ore processed using gravity concentration, with the option of flotation which needs further evaluation. The processing options still need to undergo further testing to ascertain which route is most economically viable. The pre-feasibility study is expected to be completed by the end of 2019.