Pearl Harbor oil leak is precious to some, but a worry to others

When the Arizona sank in the 1941 attack on Pearl Harbor, it held 1.2 million gallons of oil, which slowly leaks from the sunken ship. Associated Press File Photo When the Arizona sank in the 1941 attack on Pearl Harbor, it held 1.2 million gallons of oil, which slowly leaks from the sunken ship. Associated Press File Photo Image 1 of / 1 Caption Close Pearl Harbor oil leak is precious to some, but a worry to others 1 / 1 Back to Gallery

2007-02-12 04:00:00 PDT Pearl Harbor, Hawaii -- The 1.6 million visitors a year to the Arizona Memorial are told by their guides about the legends surrounding the oil that still bubbles up from the sunken battleship.

One legend holds that the oil represents the tears of the 900-plus sailors, soldiers and Marines entombed below decks since the Japanese attack of Dec. 7, 1941. Another tale says the oil will continue to surface until the last Arizona survivor dies.

But the fact is that 500,000 or more gallons of fuel oil are estimated to remain aboard the Arizona. Now the National Park Service and the U.S. Navy, which jointly maintain the memorial, are in the early stages of a comprehensive study of the sunken ship and the possibility that its oil might someday spill into Pearl Harbor, fouling the shoreline and hampering naval operations.

When 100,000 gallons of jet fuel spilled from a pipeline in 1987 -- unrelated to the Arizona -- it disrupted the Navy base at Pearl Harbor for two months. A 2005 report for the Park Service said a spill of 500,000 gallons from the Arizona "may be catastrophic."

While the scientific consensus is that such a spill is unlikely, the National Oceanic and Atmospheric Administration's Office of Response and Restoration updated its emergency plan late last year in case of a spill from the Arizona.

"It's a far more complex situation than we ever imagined," said James Delgado, noted shipwreck explorer and executive director of the Institute of Nautical Architecture. He wrote a 1989 report that led to the Arizona being named a national landmark.

Just a day before the attack that plunged America into World War II, the Arizona took on 1.2 million gallons of fuel oil. But much of it spilled into the water after an armor-piercing bomb from a Japanese warplane struck the ship's forward magazine.

An enormous explosion lifted the ship out of the water. It sank within nine minutes -- the time it now takes a Navy launch to move people from the Arizona Memorial Visitor Center to the memorial, which bestrides, but does not touch, the ship.

As part of the Park Service study, experts at the National Institute of Standards and Technology are doing computer modeling to see how the oil may be moving inside the wreckage and how soon the steel hull may become so corroded that it will collapse, allowing the oil to push to the water's surface.

The modeling used information gleaned from divers and remote-control cameras. The preliminary results suggest the oil movement is modest and that corrosion has been slowed by the mud at the bottom of the harbor, said Tim Foecke, a metallurgist at the institute.

Delgado believes the study of the Arizona will provide a key to the future of the hundreds of other ships sunk during World War II and how quickly oil inside those ships may ooze into the water.

Although the oil might pose a serious environmental risk, there is no disputing that it adds to the emotional effect of the memorial.

Visitors walk the 184-foot-long memorial and scan the "shrine room" wall that contains the names of the 1,127 men who were killed on the Arizona. Many visitors stare down at the rusted remains of Gun Turret Two and the small rainbow-colored ringlets of oil that reach the surface -- about two quarts a day.

"When people see and smell the oil, they're brought back to the world of Dec. 7," said Daniel Martinez, the Park Service historian at the memorial. "The oil is a reminder that the Arizona is a wounded and dying ship."