Federal and local regulations have been implemented in order to ensure compliance to a uniform method of burying propane tanks underground. Because a potentially harmful gas in involved, the safety of your family and neighbors depends on it. Failure to comply with established codes may end up hurting you down the line. You may get slapped with a hefty fine if discovered. Worse yet, an accident could seriously injure or kill someone.
It's not worth it. Play by the book.
Chose a location where the tank can be installed and left alone. It is illegal to put any sort of improvement over the top of the buried tank. This would include things such as outbuildings and driveways. Driveways are excluded because of how dangerous it is to have any sort of vehicular traffic passing over the top of the buried tank's location. The repeated pressure from vehicles can be disastrous.
Underground tanks must be installed at a minimum of 10 feet from a building, property line or ignition source. This is a federally mandated code, so there are no exceptions based on where you live. It is also recommended that the underground tank be installed within 100 feet of a road or driveway. This is to help ensure that the hose from the propane delivery truck can reach the tank.
Water can be disaster for an underground propane tank installation. In many areas, if you dig down a few feet in the ground, you're bound to run into water. Many a propane tank has actually risen to the surface, thus ruining the installation. The reason is because a propane tank will act like a big balloon in water. It will float because it is a hollow container filled with a gas. A common method to prevent this from occurring involves pouring wet cement in the hole upon installation. The cement hardens around the base of the tank, becoming an anchor to keep the tank in the ground.