Gulf of Mexico Has Long Been Dumping Site

There are around 4,000 offshore oil and gas platforms and tens of thousands of miles of pipeline in the central and western Gulf of Mexico, where 90 percent of the country’s offshore drilling takes place.

At least half a million barrels of oil and drilling fluids had been spilled offshore before the gusher that began after the April 20 explosion, according to government records.

Much more than that has been spilled from pipelines, vessel traffic and wells in state waters — including hundreds of spills in Louisiana alone — records show, some of it since April 20.