Don't you have to remove some overburden when building a mine?
https://markets.businessinsider.com/news/stocks/aecon-agrees-to-sell-contract-mining-business-to-north-american-construction-group-1027586160
Aecon's Contract Mining business provides overburden removal and environmental reclamation services through a dedicated fleet of earth-moving equipment
And look at this other deal in Sept. that North America Construction did..
https://agoracom.com/ir/Noront/forums/discussion/topics/714952-nac-nuna-noront-nnn
Yep, judging by the projects below and experience...Nuna was definitely a good pick for NAC.
https://static1.squarespace.com/static/527e42c4e4b0aea5e0569d9b/t/58efe79ee6f2e13ee36c3664/1492117488318/5+-+Escalante+-+Nuna.pdf