The Coast Guard was monitoring an oil spill cleanup on Thursday, four days after it poured into a Louisiana swamp southwest of Baton Rouge.
An estimated 4,000 gallons of oil spilled Sunday while WCC Energy Group LLC was piping oil from wellheads into a barge tank used for storage, Coast Guard spokesman Riley Perkofski said in emails.
A call to WCC Energy Group's office was not immediately returned.
The Coast Guard has not received any reports of oiled wildlife, and the spill's cause is being investigated, a news release said.
The spill occurred near Bayou Sorrel in Iberville Parish, at a site about 20 miles southwest of Baton Rouge, Perkofski said.
The company stopped the spill and hired a cleanup company, the news release said. It said OMI Environmental Solutions has put oil-absorbing boom around the spill, with a skimmer and absorbent materials inside it to recover oil.
Federal regulations classify a 4,000-gallon spill as medium sized.
Bayou Sorrel became notorious in Louisiana after fumes at a hazardous waste dump, also about 20 miles southwest of Baton Rouge, killed a 19-year-old trucker. Kirtley Jackson's death prompted the legislature to pass Louisiana's first hazardous waste law in 1978. The 265-acre dump was cleaned up as a Superfund site, and was taken off the Superfund list in 1997.