PHILADELPHIA – An estimated 473,500 gallons of crude are missing from a damaged oil tanker in the Delaware River, the Coast Guard said Tuesday, indicating that the weekend spill could be considerably worse than thought.
The amount is roughly 15 times greater than the 30,000 gallons of oil that ship’s engineers said had spewed from the Greek tanker as it maneuvered into a marine terminal owned by Citgo Petroleum Corp. in West Deptford.
It remained unclear Tuesday whether all of the missing oil had spilled into the Delaware River. Some of the heavy crude may have collected in an empty ballast tank on the port side.
A leak of all 473,500 gallons into the Delaware would be a “worst-case scenario,” said Coast Guard Capt. Jonathan D. Sarubbi, who is overseeing the investigation and cleanup.
The worst spill on the Delaware occurred in 1989 when a tanker ran aground in Claymont, Del., dumping 300,000 gallons of oil into the river.
Michael Hanson, spokesman for the company that manages the ship, said he did not think the spill would be much worse than initially believed.
“It’s not just gushing out of there,” he said.
By Tuesday, the spill had spread significantly, affecting patches of shoreline in a 44-mile stretch from the Salem nuclear power station to the Tacony-Palmyra Bridge.
The hardest-hit sections, however, remained along the 10 miles between the southern end of Little Tinicum Island and the Schuylkill, Coast Guard officials said.
The oil sheen reached within three miles of drinking-water intakes for South Jersey and Philadelphia.
The drinking water is not currently threatened, but precautions are being taken, Bradley Campbell, commissioner of the New Jersey Department of Environmental Protection, said Tuesday. Officials are testing the drinking water regularly.
“It’s close enough that we need to be alert,” Campbell said.
Investigators had yet to determine what ripped the hull of the Athos I open.
But some speculated that the hull had struck a 14,000-pound, 14 1/2 -foot-wide propeller that fell off a dredge boat owned by the Army Corps of Engineers in April and was not recovered.
Local history buffs even mused that the ship had gotten snagged on an iron-spiked booby trap placed in the river to skewer British ships during the Revolutionary War.
Ed Levine, oceanographer for the National Oceanic and Atmospheric Administration, who is assisting in the investigation, said officials had not ruled out the role of tides, which would have been lower than usual because of a full moon Friday night. Tide charts show that the spill was discovered about 90 minutes after low tide in that section of the river.
The number of cleanup workers has swelled from 557 to 730, who helped place 40,000 feet of booms designed to block the oil’s spread, particularly into ecologically sensitive tributaries. Workers have recovered about 6,300 gallons of oil, officials said.
Between 500 and 1,000 birds are believed to have been “oiled,” Campbell said. Most are common birds, such as Canada geese, gulls and ducks.
Two pairs of bald eagles on Mantua Creek and Monds Island in New Jersey are partly covered with oil. The birds are still mobile, and rescue workers were trying yesterday to develop a plan to capture and clean them, Campbell said.