hike with Captain - Cuchara, CO - concrete building (part 2) - what is it?

As I was making the video, I accidently turned off the phone camera. that explains why this is part 2. As explained in part 1, also on Rumble, we were walking up the ski slope and noticed this large concrete industrial building about 3/4 of the way to the top. What is it? Let's go see!