ANCHORAGE, Alaska (AP) -- A federal pipeline safety office says natural gas leaking from an underwater pipeline in Alaska's Cook Inlet may have started flowing in December.
Gas from the pipeline was spotted bubbling to the surface Feb. 7.
But the U.S. Pipeline and Hazardous Materials Administration says a flow analysis indicates it started leaking in late December.
The agency has issued a proposed safety order requiring the line to be repaired by May 1 or shut down.
Pipeline owner Hilcorp Alaska, LLC, has 30 days to respond.
Hazardous winter conditions including sea ice and strong tides have prevented divers from repairing the leak.
The company estimates 210,000 to 310,000 cubic feet of gas daily is leaking into winter habitat of endangered beluga whales.
Environmental groups contend the gas is a threat to belugas.