In a very cloudy alley at the fuel plant there are two pedestals. One is tipped over one is not.
Sprint down the alley and then jump on the upright pedestal.
Then without stopping sprint on the tipped over pedestal and jump at the very edge of it.
You should land on a big pipe.
If you are lie down and crawl through the wall you will have a view of a lot of the map and you can kill anyone going down the alley.