For tanks above ground, the main danger is explosion, and the rules are a bit more specific. They also must be registered with the proper authorities. They must be located at least 40 feet away from any buildings and have no combustible materials anywhere nearby. Tanks should have stickers that read “FLAMMABLE–KEEP FIRE AND FLAME AWAY.”
To prevent evaporation of the diesel and its escape into the atmosphere, tanks should be oriented in an east-west direction and be painted white, so they’re hit by and absorb minimal heat from the sun. Check regularly for corrosion and the leaks that may result, and be sure to report any problems to the state and federal environmental departments.
Most importantly, if you’re installing a diesel storage tank, double and triple check the rules. Breaking them comes with a heavy punishment, and for good reason. A poorly installed or maintained tank can result in the contamination of millions of people’s drinking water, and it doesn’t take much imagination to picture the damage that can be wrought by an enormous exploding in your backyard.