Retired Coast Guard Adm. Thad Allen is stepping down from his role in overseeing the BP oil spill response, a sign that management of the environmental disaster is entering a new stage.

President Barack Obama tapped Allen to oversee the effort in May, shortly after the rig explosion in the Gulf that sent oil gushing into the waters until mid-July, when BP officials finally plugged the well.

Obama praised Allen, who is taking a job with RAND Corp., for his “outstanding leadership” of the cleanup effort.

“At a time when he could have enjoyed a well-deserved retirement from the United States Coast Guard, Adm. Allen stepped up to the plate and served his country when his skills and experience were urgently needed,” Obama said. “This unprecedented response effort simply could not have succeeded without Adm. Allen at the helm, and the nation owes him a debt of gratitude.”