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NEW ORLEANS (AP) – With a midnight Monday deadline approaching to file claims under a 2012 settlement over the BP Gulf of Mexico oil spill, the claims administrator said he expected a last-minute rush of filers.

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“There’s always a rush, for myriad reasons,” Patrick Juneau said in a telephone interview last week. Juneau said more than 328,000 claims had been filed as of the middle of last week. More than 20,000 of those were filed last month.

Juneau said there has been an uptick in the number of filings as the deadline approaches. He announced last week that claims centers in Florida, Mississippi, Alabama, Louisiana and Texas would be open until midnight Monday to handle claims.

As of mid-April, more than $5 billion in claims had been paid out, according to Juneau’s office.

The spill began when the Deepwater Horizon offshore drilling rig exploded in flames April 20, 2010, killing 11 workers and spewing oil from the sea floor for 87 days.

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The 2012 settlement agreement was hailed by all involved when it was signed, but soon became the subject of contention over its interpretation by the district court in New Orleans and by Juneau, the court-appointed claims administrator. BP said payments were being made to some entities whose losses weren’t caused by the spill. Courts rejected that argument.

In 2012, BP estimated it would pay roughly $7.8 billion to resolve claims under the settlement. BP later said it couldn’t give a reliable estimate for the deal’s total cost. In its first-quarter earnings report for 2015, BP said it could estimate at least a $10.3 billion cost. But it stressed that there was no way of knowing how many claims would be filed by the deadline and that the total cost would likely be significantly higher.

Claims may be filed in person, by phone or online.

Juneau’s office will likely have a preliminary figure on the number of claims filed by the deadline sometime on Tuesday. That number won’t be final, however, because mailed claims will be accepted if they are postmarked June 8.

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