Last pic looks like an aerial map like the ones I use to use for scouting. Its some sort of survey crew is my guess.
They're not dressed in work clothes, but who knows. Interesting pic. I once scouted a large property in shorts and flip flops, wanted to buy a piece of it. Didn't realize my legs were bleeding until I knocked on the owners house to make a deal. He asked why I was bleeding, so I told him. He asked why I was trespassing on his property, I said I'm not Sir you don't own the property yet...had done my research....but I want to buy this particular piece of ground right here.....he said "damn Son, you really want that plot don't you?"
Today if I would have had pics of me then walking that ground I would have raised an eye brow for sure.