Shell reports spill at Gulf of Mexico drill site

The US Coast Guard is investigating a 13,000-gallon spill from an oil rig leased to Shell, operating around 26 miles southeast to the site of the BP Plc Macondo oil well disaster last year.

According to the US Coast Guard, the spill of either drilling fluid or oil mixed with drilling fluid was first reported on Sunday by the Deepwater Nautilus rig of Transocean Ltd that was drilling a well at Shell's Appomattox discovery.

Shell spokewoman Kelly op de Weegh said in an email that  the company could confirm it had suffered a loss of 319 barrels of drilling fluid, Reuters reported.

A booster line that provided additional drilling fluid had sprung a leak and it was separate from the well she added.

She added, the leak was isolated, stopped and remedial action had been approved by BSEE (the US Bureau of Safety and Environmental Enforcement), which included temporarily abandoning the well, and making appropriate repairs.

According to Coast Guard spokesman Steve Lehmann, the Coast Guard was trying to determine what material had spilled.