Filminera Resources Corp. (FRC) engaged AMH to conduct a parallel geotechnical, hydrologic and hydraulic study for the proposed Stage 11 Tailings Storage Facility (TSF) Reservoir and Spillway Design located at Brgy. Puro, Aroroy, Masbate. The continuous production of gold at the mine site entailed further expansion of the TSF. To anticipate this, FRC prepared for the Stage 11 embankment raise to RL 59m. The Stage 11 includes four (4) meter raise of the Main Embankment, Saddle Dam 1 & 2, Saddle Dam 4, and Saddle Dam 8. 

Hydrologic and hydraulic studies were conducted to assess the potential of the current embankment crest elevation at RL 59m in terms of storage capacity, and determine the required Stage 11 spillway crest elevation, as well as the freeboard requirement, prior to the expansion of the TSF. AMH developed the design criteria and parameters for this study consistent with the provisions of Australian National Committee on Large Dams, Incorporated (ANCOLD) 2012 Guidelines for Tailings Dams. Slope stability of the TSF embankments based on the new design were also assessed, which mostly involved downstream construction.