What is the impact of Canadian oil sands on oil reserves and supply to the United States? What new technology has revolutionized the natural gas scene in the United States? Describe surface mining as...

What is the impact of Canadian oil sands on oil reserves and supply to the United States? What new technology has revolutionized the natural gas scene in the United States? Describe surface mining as it is practiced in the southern Appalachians. What phenomenon may restrict the consumption of fossil fuels, especially coal, before resources are depleted?