That's quite an aggressive investment. Granted, that Bitmain has done everything to keep mining a monopoly I don't think this could turn out too well. Bitmain is always going to have cheaper electricity, labor and everything required to produce better and more equipment. At the end of the day, that's why so many mining companies went bankrupt.
I'm sure it went on a process. A large company like that wouldn't blindly invest onto something that they don't know.
That $60m was not a one man and one day decision. Also, they can make partnerships and hire some advisors to know whats best to do with it. (they might already have)