In a letter to BP's Chief Executive Officer Bob Dudley, they said there are lingering concerns about the long-term impacts of the 2010 oil spill.
They point to a report in The Washington Post that stated a September discovery of residual oil sheen likely came from a drill pipe about a mile below the sea's surface.
"We request a briefing, by Oct. 30, on possible causes of this recently reported oil release," the lawmakers said in their letter to Dudley.
The U.S. Coast Guard, BP, and the National Oceanic and Atmospheric Administration worked to assess sheen observed in the Gulf of Mexico in late September. The Coast Guard said it was able to confirm the sheen was from the well that failed in 2010.
BP in mid-September said it confirmed that residual oil from the 2010 oil spill in the Gulf of Mexico was pushed onshore by Hurricane Isaac, which hit the southern U.S. coast in late August.