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It seems to be the lost art. None of the contractors, architects and very few of the engineers I've had contact with have ever heard of it... a cheap earthing system that consistently outperforms typical ground rod installations. This is a proven concept, but before I describe it, let me make it clear that I take no credit for its design.
During World War II, a retired Vice President of Underwriters Laboratories, Herbert G. Ufer, developed it for the U.S. Army. Igloo shaped bomb storage vaults were being built, and possible static and lightning induced detonation problems were of concern. Ground conductivity was poor, and to be effective enough, ground rods would have to be driven several hundred feet. After much research and testing Mr. Ufer advised the Army to make connection to the steel bar that would internally reinforce the concrete foundation. He had determined that concrete was more conductive than all but the best soil, and that this improved semiconducting characteristic would enhance surface area contact with the surrounding soil. The wire ties normally used would be extra secure, and attention would be given to bonding or welding the lattice- type network together. The Army adopted the idea, and built the vaults as
specified. After construction ground resistance tests were made. No measurement exceeded five ohms. This value was considered extremely low for the local soil conductivity. Later tests confirmed stability. Mr. Ufer went on to develop the concept of concrete encased grounding electrodes. Many of his findings are detailed in IEEE Transactions paper # 63-1505. His system has since been used by the military, utility companies, Lake Tahoe lifts, and industry throughout the country. Why not broadcast stations? After reading an obscure 1967 paper citing actual tests and comparisons to conventional systems written by Wismer & Becker Engineers, I decided to give it a try.