The U.S. Department of Interior has approved Shell’s plan for deepwater oil and natural gas exploration in the Gulf of Mexico, the first such exploration plan since the BP oil spill. Shell is planning to drill three exploratory wells in nearly 3,000 feet of water about 130 miles off the Louisiana coastline. There are 13 other deepwater oil and natural gas exploration plans pending approval. Meanwhile, the U.S. Coast Guard is investigating the source of another large oil spill in the Gulf of Mexico. The Times-Picayune reports that emulsified oil and tar balls have been washing up along a 30-mile stretch of beach in Louisiana.