DIY tool build projects are one of my favorite topics. Recently, I Heart Robotics posted documentation of a DIY cleanroom build to further particle sensitive schemes like hacking a Hokuyo Laser Rangefinder. The essential elements are a sealed box, some workspace, and a supply of filtered air for positive pressure inside the box.
Most parking lots may resemble a man-made wasteland even with cars sitting on top of them. But now they can serve a dual purpose by helping filter out pollutants in rainwater that might reach underground water sources.