Proposed West Coast coal export terminals for shipping coal mined in Wyoming and Montana to Asia are facing increasing scrutiny.

If all the Pacific Northwest projects were built, as much as 150 million tons of coal could be exported annually, equal to almost 50 percent more than the country's coal export output for 2011, The New York Times reports.

While the U.S. currently has nine coal export terminals, all are on the East Coast. British Columbia has three terminals.

One of the export sites under consideration is the Port of Morrow project near Boardman, Ore, in which Australian coal firm Ambre Energy would invest $159 million.

Coal would be transported by rail to the port, then transferred to covered barges, which would ship the coal down the Columbia River to an enclosed transloading barge at the Port of St. Helens for transfer to an ocean vessel.

Gary Neal, the general manager of the Port of Morrow, says the port handles about 60 trains a year, transporting a variety of commodities. The coal facility would increase that to roughly 600 trains.

"If this product doesn't go through here, it's going to go through Canada or the gulf or somewhere else," he told the Times.

The Times' report highlights the tension between Boardman, an area that boasts clean energy advances, and concerns of environmental groups.

"Oregon has a very strong brand, a very strong reputation as an innovative state, as a place where there's clean water, clean technology, clean energy," Brett VandenHeuvel, executive director of environmental advocacy group Columbia Riverkeeper told the Portland (Ore.) Business Journal.

"Hitching our wagons to sending coal to China is exactly the opposite direction we want to go."

The Oregon chapter of the Sierra Club, pointing to the nation's progress in ending its dependence on dirty coal as well as in boosting clean energy development, says that "Big Coal threatens this progress with new plans to further tear up our land and poison our air and water by shipping millions of tons of U.S. coal to be burned in Asia instead."

The organization further notes that mercury emitted from existing coal fired power plants in China is already finding its way into Oregon's rivers, streams and fish.

The Port of Morrow project, and others like it, would require permits from the U.S. Army Corps of Engineers. The Environmental Protection Agency, in a letter to the USACE this month about the Boardman project noted that "two of our primary preliminary concerns relate to the potential for adverse effects from project-related coal dust and diesel pollution."

"Coal dust is a human health concern because it can cause pneumoconiosis, bronchitis and emphysema," the EPA letter stated.

But supporters of the Port of Morrow project say it environmental precautions would be carried out, including coal rail cars sprayed with a dust suppressant, enclosed conveyor belts and covered barges.