dical and/or educational facilities, housing shortages, sewage disposal problems, and a lack of recreational activities for new residents. The University of Denver separates problems associated with a mining-specific boomtown into three categories: deteriorating quality of life, as growth in basic industry outruns the local service sector's ability to provide housing, health services, schooling, and retail declining industrial productivity in mining because of labor turnover, labor shortages, and declining productivity an underserving by the local service sector in goods and services because capital investment in this sector does not build up adequately The initial increasing population in Perth, Western Australia, Australia (considered to be a modern-day boomtown) gave rise to overcrowding of residential accommodation as well as squatter populations. "The real future of Perth is not in Perth's hands but in Melbourne (and London) where Rio Tinto and BHP Billiton run their organizations", indicating that some boomtowns' growth and sustainability are controlled by an outside entity. Boomtowns are typically extremely dependent on the single activity or resource that is causing the boom (e.g., one or more nearby mines, mills, or resorts), and when the resources are depleted or the resource economy undergoes a "bust" (e.g., catastrophic resource price collapse), boomtowns can often decrease in size as fast as they initially grew. Sometimes, all or nearly the entire population can desert the town, resulting in a ghost town. This can also take place on a planned basis. Since the late 20th century, mining companies have developed temporary communities to service a mine-site, building all the accommodation shops and services, using prefabricated housing or other buildings, making dormitories out of s