Surveillance aircraft sent to possible oil spill reported in wake of Ida

The US Environmental Protection Agency said on Thursday it has dispatched a surveillance aircraft to an area in Louisiana hard hit by Hurricane Ida that includes a refinery where an apparent oil spill has been reported.

The aircraft dispatched from Texas will gather data on the Phillips 66 refinery and other priority sites, an EPA spokesman told Reuters.

"EPA's ASPECT aircraft - the Agency's airborne real-time chemical and radiological detection, infrared and photographic imagery platform - has been activated to support the state of Louisiana," the spokesman said.

Phillips 66 said earlier that flooding had occurred at its Alliance Refinery and a sheen of unknown origin in some flooded areas of the refinery had been discovered.

"At this time, the sheen appears to be secured and contained within refinery grounds. Clean-up crews are on site. The incident was reported to the appropriate regulatory agencies upon discovery", the company said.

"A full post-storm assessment remains underway at the refinery. An investigation into the cause/origin of the sheen will be conducted. The refinery remains shut down", it added.

The Associated Press has also reported a possible spill near an offshore rig in the Gulf of Mexico after a review of aerial images of the disaster zone taken by the National Oceanic and Atmospheric Administration.

The photographs appeared to show a miles-long brownish-black slick in the waters south of Port Fourchon, Louisiana.

The rig had Enterprise Offshore Drilling marked on its helipad. Enterprise Offshore Drilling said in statement on its website that its rig had not suffered any damage or failure and that "no environmental discharges had occurred from our facility".

The US Coast Guard told the AP it also had an aircraft fly over the refinery as well as to the Gulf of Mexico. The Coast Guard did not immediately respond to a request for comment late on Thursday.

Ida, one of the most powerful hurricanes ever to strike the US Gulf Coast, made landfall on Sunday in Louisiana, destroying entire communities.