Tedro, I was born raised, & more than likely will die in Omaha.
Nebraska is NOT new to mining & the impacts of it. Some of the State run recreation areas & lakes are direct result of limestone mining. Ash Grove Cement Co. has been in Louisville, NE for nearly 100 years!-- that has taken ALOT of stone. There are some safety stats in this article.
Nebraska has been mining Uranium since 1991 in the northwest corner of the state(Crow Butte). This operation currently has 2, or 3 permits under review for expansion as the primary vein has become less productive in terms of %.
As far as CO2 emissions. If Scandium & Niobium are used in the lightweight revolution, how much CO2 will be ELIMINATED by all the lightweight, & or electric vehicles in Omaha & Lincoln alone?