(1) Getting near the plant Deus Ex: HR Guide

The mission starts on the landing area on the third level. Go inside the building. After you get inside, explore lockers and consider talking to one of the SWAT members #1. You can ask him #2 about the terrorist leader, a possible number of enemies inside the plant and SWAT plans regarding the assault on the plant.

Go further, looking for more lockers. Use the door and you'll be contacted by Frank Pritchard #1. He will tell you how you can get inside the plant. Use the ladder twice #2 trying not to make too much noise.