GR Engineering Services (GRES) is to act as engineer for the definitive feasibility study on AVZ Minerals’ 60%-owned Manono lithium and tin project in the Democratic Republic of Congo, the Australia-listed developer said.GRES, based in Perth, Western Australia, is an engineering group with significant experience in study management and the engineering design and construction of resource projects in Western Australia and globally, both as EPCM and EPC contractor, AVZ said.Manono, meanwhile, was recently the subject of a scoping study. This study showed a 5Mt/y project could produce around 1.1 Mt/y of concentrate at a minimum of 5.8% Li2O concentrate.AVZ said: “The GRES team nominated for this engagement have appropriate experience in Africa, including in the DRC, where GRES recently provided operational support and optimisation studies at the Kipoi copper project (Tiger Resources).AVZ’s Managing Director, Nigel Ferguson, said: “The appointment of GRES as the DFS engineer is a significant milestone for the Manono project as its work is highly regarded by leading financiers and lending institutions.”Other DFS work streams are continuing to schedule including the metallurgical test work, AVZ noted. A 1 t sub-sample of the bulk sample has been sent to ALS Minerals in Perth for comminution testwork, with results from this expected soon.The dewatering program for the Roche Dure pit has commenced. Approval to dewater the Roche Dure and M’Pete open pits was given to AVZ’s DRC management company, Dathcom Mining SAS, in mid-May by the Mines Environmental Protection, a section of the DRC Department of Mines. The approval was contingent on the building of a silt settlement pond and a water treatment facility into the existing dewatering channel, which has since been completed.