Dominion Virginia Power Company is hoping this week to clear the last major hurdle to construction of a $1.8 billion coal-fired power plant in Wise County Virginia. The state Air Pollution Control Board held a public hearing yesterday that drew hundreds to J. J. Kelly High School. The board will discuss plans today for the plant and may vote on whether to issue a permit. The plant’s projected emissions of sulfur dioxide and mercury have prompted an outcry from environmentalists. The Department of Environmental Quality has proposed a requirement for lower emissions. The State Corporation Commission has already approved its permit for the plant, which proponents have hailed as a source of jobs in the economically depressed region and a new market for Virginia coal. A decision could come soon.