INDIANAPOLIS, IN (KDAL) - Calumet Specialty Products has announced that it will explore the feasibility of building and operating a crude oil loading dock on Lake Superior.  It would be built near its Superior refinery and would be designed to load ships with heavy Canadian and light Bakken crude oil for shipment.  Calumet is based in Indiana and is the owner of the former Murphy Oil Refinery in Superior.  The company is in talks with potential customers and partners and the project could be fully operational during the 2015 shipping season.