Uncomfortable standoff!

It was sort of funny, but I wimped out in the end. As I arrived at the Rachel Gate, a white semi with government plates showed up at the same time. I pulled way to the side of the road with plenty of room for the semi to pass by but he didn't move. He stayed right where he is in the picture. The guard opened the door and closed it quickly. The truck just stayed there. I thought maybe he wasn't moving because I had my camera out, so I put it away. He still didn't move. A few minutes passed and there was no movement. Some more minutes passed and still no movement. I started feeling a little uncomfortable at this point. I go out there quite a bit and have never had a problem with the security and didn't want any issue this time. I waited a few more minutes and then finally decided to leave. The semi won! He waited for me to be plenty far away and left. He headed down a different road than I was on. He cut through Rachel and went out towards Warm Springs. I was waiting for him at the entrance to the back gate road before you get to Rachel, so I didn't get any other pictures of him. He appeared to be just your usual semi, but he definitely didn't want any more photos taken. Everything else was quiet as usual around the perimeter today!