General Discussion Topics, page-130150

I can see how avoiding falling down big holes would add cost. At least it is only temporary.

“Furthermore, mining costs are currently elevated with activity focused in the area of pre-existing underground mine works dating from the 1950s. Unit mining costs are expected to improve once operations have moved past the old mining works.”

https://www.juniorminingnetwork.com/junior-miner-news/press-releases/2224-nasdaq/pll/155444-piedmont-lithium-provides-corporate-update.html#:~:text=Piedmont%20expects%20to%20begin%20deliveries,strategic%20review%20of%20NAL%20operations.