Creosote from both oil shale and petroleum, and are known as oil-tar creosote when derived from oil tar, and as water-gas-tar creosote when derived from the tar of water gas. Creosote also has been made from pre-coal formations such as lignite, yielding lignite-tar creosote, and peat, yielding peat-tar creosote. The term creosote has a broad range of definitions depending on the origin of the coal tar oil and end use of the material. With respect to wood preservatives, the United States Environmental Protection Agency (EPA) considers the term creosote to mean a pesticide for use as a wood preservative meeting the
East Broad Top Railroad and Coal Company of the oldest railroad roundhouses in the US still in operation, was built in 1882. A coal cleaning plant and a full maintenance shops complex were also built, bridges were upgraded from iron and wood to steel and concrete, wood rolling stock was replaced by steel, and modern high-powered steam locomotives were bought from the Baldwin Locomotive Works of Philadelphia. In the 1950s, coal demand plummeted as homes and industries switched to cheap oil and gas. The last nail in the coffin came when the silica brick plants in Mount Union converted to oil and gas and not enough coal