After the Deepwater Horizon oil spill in the Gulf of Mexico in 2010, the largest in U.S. history, there was a lot of talk about the possibility of offshore drilling being scaled back. Instead, the opposite has happened. Since the moratorium imposed on deep-water drilling in the U.S. in May 2010 was lifted in October of that year, offshore exploration and drilling in the Gulf of Mexico has continued uninterrupted and taken on new momentum, as it has around the world. Today, deep-water drilling—500 feet or more below the surface of the sea—remains the next big frontier for oil and natural-gas production. Some environmentalists have expressed concerns that expanded offshore drilling poses new risks of spills and other damage to the environment. “We still don’t know all the impact of the Deepwater Horizon spill on the ecosystem,” says Sean Dixon, a water-policy attorney at environmental-protection group Clean Ocean Action […]