Navy divers rehearsing tricky salvage mission
By Mike Gordon
Advertiser Staff Writer
Out on the mouth of Pearl Harbor, far from piers lined with Navy ships, teams of salvage divers are earnestly rehearsing for the grim task of recovering bodies from the Ehime Maru.
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Their preparation over the past few weeks is aimed at getting them safely in and out of the Japanese fisheries training vessel once the Navy moves it from 2,000 feet to shallow water near the reef runway.
Navy divers have been practicing for the salvage of the Ehime Maru to make the operation as safe as possible.
The Ehime Maru sank Feb. 9 after it was accidentally rammed by a Navy fast-attack submarine nine miles south of Diamond Head.
Nine people aboard the Ehime Maru were lost in the collision and may be inside the hull. The Navy has pledged to return their bodies to their families.
Although moving a damaged 830-ton ship from this depth has never been done before, sending salvage divers to 115 feet and inside a wreck is a common task for Navy divers.
But there are risks.
"There is always a danger in anything we do," said Chief Warrant Officer 3 George Primavera, coordinator of the mission. "The way we try to be prepared is we reinforce procedures that can limit or remove the danger factors."
Their training is usually intense. It's not uncommon for them to dive beneath submarines or work in the dark depths beneath hulking aircraft carriers, Primavera said.
The divers will be part of a 66-diver contingent. They will work in shifts aboard a civilian barge that will anchor over the Ehime Maru once it is moved to the shallow-water site.
The Navy has nine "last-known locations" for the missing people, but only expects to find five to seven sets of remains.
Divers will only have 90 minutes from the time they enter the water until the time they must begin a carefully orchestrated ascent to the surface.
Returning from 115 feet creates a danger that nitrogen in the bloodstream could expand, leading to the bends and other problems. Divers are taught that ascending slowly is similar to slowly opening a can of shaken soda to safely release the bubbles.
Pausing at 40 feet for three minutes and then at 30 feet for seven minutes allows some of the gas buildup to escape from the divers' bodies, said Primavera, a veteran diver who helped with the salvage of TWA Flight 800 and the space shuttle Challenger.
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But the next five minutes are key to a diver's survival, he said.
After returning to the surface, the divers will have only minutes to get out of their dry suits.
Divers have a minute to get out of the water, 3 1/2 minutes to get washed down with a biodegradable soap and out of their dry-suits and then a scant 30 seconds to get into a decompression chamber, he said.
"You cannot exceed that time," Primavera said. "This is a critical phase of the operation."
As Primavera explained the challenges, a diver climbed out of the harbor water for the hurried transition. Standing nearby, another diver held a stopwatch.
The scrubdown is important because the Navy expects that divers will encounter diesel fuel or lubrication oil inside the Ehime Maru. That won't mix well inside a decompression chamber, where the divers will breathe 100 percent oxygen much of the time.
"If you mix petroleum and oxygen there is a possibility of an explosion," said Cmdr. Rob Fink, commanding officer of the Navy divers who will enter the Ehime Maru.
The rigging of the Ehime Maru has progressed around-the-clock since a civilian vessel, Rockwater 2, arrived Aug. 7. The Navy hopes the vessel can rig a cradle beneath the Ehime Maru, pluck it from seabed and move it to the reef runway location.
Preparations were hampered slightly by rougher-than-normal seas but the Navy said the lift can still be accomplished within a 30-day window of opportunity — no later than mid-September.
Winds of 10 to 25 mph and swells of 8 to 10 feet forced Rockwater 2 over the weekend to leave the site and find calmer conditions closer to O'ahu. The ship needed a place to safely lower rigging equipment over the side and stabilize onboard equipment.
All of the rigging is being done by remotely operated vehicles guided by technicians aboard Rockwater 2.
Special underwater drilling equipment needs to be placed on the bottom and holes bored beneath the Ehime Maru so a huge cradle can lift the ship.
On Saturday, the Navy officials in Japan plan to show a video of the work to relatives of the nine missing people.
Even as they view it, the divers will probably be training, donning their heavy, red dry-suits and yellow helmets, hooking up to an air hose and slipping into the harbor.
"It may look manpower intensive, but everything here is focused on safety," Fink said. "The guy at the end of that hose is the most important person in the world to us."
