SIOUX FALLS � A Texas company looking to build a $10 billion oil refinery in southeastern South Dakota has revised its greenhouse gas emission estimates after omitting part of its refining process from an earlier air permit submission.
Hyperion Resources told the South Dakota Department of Environment and Natural Resources late last month that it inadvertently left coke drum steam vents out of its estimates, which would raise the refinery�s expected methane emissions from 500 tons per year to 980 tons per year.
Hyperion spokesman Eric Williams said Thursday that the change will have a minimal effect on the plant's total expected greenhouse gas emissions, adding 10,100 tons per year of carbon dioxide equivalent to its expected annual emissions of about 16.9 million tons.
The state Board of Minerals and Environment granted Hyperion an air quality permit in August after finding that the Dallas-based company had met the requirements set in state laws and rules. Board members endorsed the Environment Department's recommendation to issue the permit for what would be the first new U.S. oil refinery built since 1976.
The Sierra Club and local groups Save Union County and Citizens Opposed to Oil Pollution have filed a lawsuit in state court arguing that the permit should be thrown out because it does not address some environmental issues.
The existing air quality permit requires Hyperion to begin actual construction of the Hyperion Energy Center by Feb. 20. In June, the firm submitted a request to extend the construction deadline to Aug. 20, 2012. That request is pending.
Hyperion�s refinery north of Elk Point would process 400,000 barrels of Canadian tar sands crude oil each day into low-sulfur gasoline, diesel, jet fuel and liquid petroleum gas.
The project would include a power plant that produces electricity for the refinery. It would use a byproduct of the refinery process, solid petroleum coke, which would be turned into gas and burned to produce electrical power.
Hyperion officials hope to start construction late next year. The company has not released any specifics about financing,
"But as the economy is starting to pick up a little bit, so is the financing interest," Williams said.