FILE - This July 10, 2011 file photo shows the Yellowstone River flowing eastward past the Exxon Mobil refinery, in Laurel, Mont. State officials are calling on federal regulators and the oil and gas ... more 
FILE - This July 10, 2011 file photo shows the Yellowstone River flowing eastward past the Exxon Mobil refinery, in Laurel, Mont. State officials are calling on federal regulators and the oil and gas industry to provide data on the "invisible spider web" of pipelines crossing Montana waterways in the wake of a spill that dumped tens of thousands of barrels of oil into the Yellowstone River.(AP Photo/Julie Jacobson, File) less 
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Associated Press | Photo By Julie Jacobson, File
Wed, Aug 3, 2011 3:38 PM EDT