FILE - In this July 22, 2010 file photo, the sign at an entrance for the Horsehead Inc. zinc plant is seen in Monaca, Pa. Shell Oil Co. said Thursday, March 15, 2012, it has chosen this site near ... more 
FILE - In this July 22, 2010 file photo, the sign at an entrance for the Horsehead Inc. zinc plant is seen in Monaca, Pa. Shell Oil Co. said Thursday, March 15, 2012, it has chosen this site near Pittsburgh for a major new petrochemical refinery that could provide a huge economic boost to the region. (AP Photo/Keith Srakocic, File) less 
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Associated Press | Photo By Keith Srakocic, File
Thu, Mar 15, 2012 5:31 PM EDT