URBAN GROWTH VERSUS MINERAL EXTRACTION, A SPECIAL CONCERN INVOLVING AN UNDERGROUND LIMESTONE MINE

The conflict between gravel and rock extraction and urban growth is a common occurrence in populated areas. Gravel and crushed stone have a high place value, because of their large volume and low unit cost so that distance between source and construction site must be minimized. An underground limestone mine near Noblesville in central Indiana has a special effect on neighboring property values. Blast vibrations are always a concern but when effects are kept below 2 inches/second, particle velocity, no damage is induced on a sound structure. The property concerned, situated about 2 miles south of State Road 38, a few miles east of downtown Noblesville and adjacent to the White River is quite valuable because of its prime location. It is estimated that the nearest portion of the adjacent underground mine is 600 feet away from the structure and no blast damage has been observed. However, blast vibrations have been experienced when the mine was operating nearby. Since that time the active mining face has moved a greater distance away and vibrations are no longer experienced. Humans are particularly sensitive to these vibrations and known to complain at 0.02 inches/second particle velocity. The property owner plans to sell a portion of his property and was initially offered $64,000 per acre for a section to build a retirement center and nursing home. When prospective buyers learned of the blast vibrations they were no longer interested in the purchase. A change in mining operations and timing could reduce the annoying effects of blasting.