An existing water diversion dam that stores water for the project site was raised on the upstream slope. It will converted into the client’s tailings storage facility No. 5B (TSF5B) with a spillway on the left abutment and diversion conduit during operations. EDCOP was engaged to undertake the concept design, detailed engineering design and construction quality assurance/quality control (QA/QC) monitoring for the proposed TSF5B.