SAN FRANCISCO (MarketWatch) -- A retired well about 75 miles off the Louisiana coast is leaking natural gas and light oil, according to media reports Tuesday. The leak prompted the evacuation of five workers from a three-well production platform owned by privately-held Talos Energy LLC. Coast Guard officials are monitoring a hydrocarbon sheen on the surface, which extends about four miles from the well site. The Fuel Fix energy blog reported a Talos crew was permanently plugging and abandoning the decades-old well when it noticed the leak. Talos Energy President Timothy Duncan told Fuel Fix the company plans to return crew to the field and expects to have the well under control within the next 24 hours. Talos Energy is a partnership between private equity firms Apollo Global Management LLC APO, -2.32% and Riverstone Holdings. Talos acquired the well from Energy Resource Technology in February.