Myanmar Metals Ltd.'s expansion study for its Bawdwin lead-silver-zinc joint venture in Myanmar delineated two further open pit cutbacks beyond the planned starter pit.

According to the expansion study released Jan. 3, underground mining at Bawdwin is possible, but two further open pit cutbacks, namely phases two and three, "offer potential for superior outcomes relative to underground mining."

The two additional phases will target the mineral resources left unmined by the phase one open-pit mine, which will process 24.7 million tonnes of the 100.6 Mt resource at Bawdwin.

The study suggested that small-scale underground mining and exploration drilling from the starter pit floor, between the first and second phases, may be conducted to decide whether to proceed with the third phase as an open-pit cutback or an underground mine.

The Bawdwin joint venture now plans to reevaluate the proposed processing plant throughput and assess if capacity can be increased from the 2 million tonnes per annum estimated in the pre-feasibility study for the starter pit.

Myanmar Metals owns 51% of the Bawdwin joint venture, while East Asia Power (Mining) Co. Ltd. and Win Myint Mo Industries Co. each hold 24.5%.

A pre-feasibility study in May 2019 for the starter pit at Bawdwin outlined a net present value, discounted at 8%, of US$580 million, a 30% internal rate of return, and a four-year payback period.