PITTSBURGH — Gov. Tom Corbett was expected to address a rally of coal industry and mining supporters opposing stricter Environmental Protection Agency regulations being proposed to regulate pollution from coal-burning power plants.

Today’s rally at Highmark Stadium, a minor-league soccer venue, comes a day before the EPA holds two days of public hearings on the proposed regulations in downtown Pittsburgh.

Business and labor officials contend the regulations will drive up electricity prices and cost jobs in the coal and energy industries, and may not wind up cutting carbon dioxide and other emissions enough to make it worth those costs.

Some environmentalists want even stricter rules and argue that the benefits to the environment — and a boom they predict in jobs relating to more renewable, efficient energy sources — make the regulations a no-brainer.

The rally Corbett will address was organized by the Pennsylvania Coal Alliance, the American Coalition for Clean Coal Electricity, and the National Miners Association.

According to the U.S. Department of Energy, Pennsylvania was the fourth-largest coal-producing state in the country last year, accounting for 6 percent of all U.S. coal.

That’s one reason advocates for both sides have descended on Pittsburgh where they hope to sell their message before hundreds of people testify.

The EPA expects 1,600 people to speak in the four cities and has already received more than 300,000 written comments, which will be accepted until Oct. 16. The Pittsburgh hearings will run from 9 a.m. to 8 p.m. Thursday and Friday.