Politico:

The outgoing Interior Department official in charge of leasing for offshore oil drilling initially told the Minerals Management Service the day after the April 20 explosion at Deepwater Horizon that he intended to retire on June 30, administration officials say.
But Chris Oynes abruptly moved the date to May 31, informing his colleagues in an email Monday.
Oynes has worked for the Interior Department for 35 years, most recently for more than a decade as associate director for offshore energy and minerals management for the Minerals Management Service. His department at MMS, which oversees offshore oil drilling, has increasingly been under criticism for having too close of a relationship with the companies it regulates.
“This was Chris Oynes’s decision to retire after almost 35 years of public service,” an administration official said in a statement. “Shortly after the Deepwater Horizon explosion, he approached leadership at MMS and announced he would be retiring on June 30th and today he told his colleagues that he would be accelerating his retirement.”