SIOUXLAND—A state board has set a July 25 hearing in a Texas company’s request for more time to start construction of a $10 billion oil refinery in Siouxland. A previously issued state air quality permit required Hyperion Resources to begin construction by Feb. 20 of this year. The company wants to extend the deadline to August 2012. State officials have issued a draft permit allowing the extension and some changes in emissions. The state Board of Minerals and Environment will consider those issues at the July hearing. The Hyperion 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. It would be the first new U.S. refinery built since 1976.