Minisub enters USS Arizona to survey structure's integrity

By Dan Nakaso
Advertiser Staff Writer

Marc-Andre Bernier hovered in scuba gear in the shadowy water just above the deck of the USS Arizona yesterday and pointed toward an open hatch, showing the way in.

Marc-Andre Bernier of the Canadian Park Service gets set to tether a minisub at the USS Arizona Memorial. Cory Lum • The Honolulu Advertiser

On the monitors inside the tiny work room, the images sent back by Remotely Operated Vehicle No. 733 revealed mundane details of life aboard a battleship that is recognized as a national monument to the attack on 1941 Pearl Harbor and a memorial to the 1,177 sailors who died with it.

In an aft bathroom, a tube of toothpaste still sat in a cup. A toilet paper holder appeared to be in working order.

But yesterday's dive was a mission of science designed to begin gathering data about how long the wreckage can hold together.

In September the minisub scouted the Arizona for National Geographic, the Discovery Channel and the History Channel. Yesterday, the same 8-pound sub was fitted with an ultrasonic gauge designed to press up against parts of the Arizona, measuring the thickness of its metal.

It was a test run of the kind of experiments to follow over the next week as a team of divers and researchers from the National Park Service, its counterpart in Canada, two universities and the Army and Navy continue trying to figure out how much longer the Arizona will stay intact.

A matter of fuel oil

Unfortunately for the researchers, yesterday's first results were hard to trust.

John Makinson, a materials research specialist from the University of Nebraska-Lincoln, read out the numbers coming off of the ultrasonic gauge attached to the nose of ROV No. 733.

Instead of precisely determining the thickness of the wall next to the bathroom, the readout instead offered an array of options:

"Point 2-3," Makinson said to the others crowded around the images being sent back to the room inside the white memorial, "7 point 2, 4 point 4, point 3-4, 4 point 4. There's no way to tell, it's bouncing around so much."

Finally Makinson said to his colleague from Nebraska, professor emeritus Donald Johnson: "Write down 4.4. That's the most stable reading. But there's no way you've got 4 inches of steel there."

The research is important if the park service is to know how much longer the Arizona will hold back whatever remains of the million-plus gallons of fuel oil that went down with it.

"It's not an enormous undertaking to cut into a ship and pump out oil," said Larry Johnson, chief of the National Park Service's Submerged Cultural Resources Unit, based in Santa Fe, N.M. "But we have to be respectful that this is a war grave and a war memorial. That's why this particular site creates such a complex problem."

The mini-sub didn't detect signs of human remains in September, and the park service believes they have deteriorated. Still, only a handful of divers certified through the park service are even allowed to be on the outside of the ship.

Those divers drop 30 feet down what's left of gun turret No. 4 to deposit the remains of sailors who were assigned to the Arizona at the time of the attack and wish to be buried with their shipmates.

Interior access vital to study

Until recently there seemed to be no reason to peer inside the Arizona any farther, Johnson said. However, now the technology exists to unobtrusively steer through the passageways with the remotely operated mini-sub and at the same time measure things like pH, dissolved oxygen and monitor the erosion of the metal.

Larry Murphy of the National Park Service holds the VideoRay remote-controlled vehicle that contains an ultrasonic thickness gauge to collect data on how much the USS Arizona has deteriorated. Cory Lum • The Honolulu Advertiser

The Army's 29th Engineer Battalion and 70th Survey Platoon helped set up 40 monitoring stations on top of the deck of the wreckage. The battalion's global positioning system technology is so precise that it can detect changes of less than a centimeter, Johnson said.

A microbiologist from South Carolina is studying the microbial community that has surrounded the Arizona using DNA technology that didn't exist five years ago. Bernier, a marine archaeologist with Parks Canada's Underwater Archaeological Services unit, is learning from the Arizona research and offering tips from the Canadians' experience with wrecks.

And a Pennsylvania company named VideoRay has offered the use of its technology and one of its $11,500 mini-subs, normally used to inspect water tanks and oil rigs.

The only cost to the government is the airfare to send the dive team from New Mexico.

"Like any other governmental agency, we're hurting for money," Johnson said. "Here, we're actually doing a lot with a little."

The month's worth of data will take several more months to pore over. The information will inevitably lead to more questions and ideas about collecting even more clues, Johnson said.

But for the next week, at least, the divers and researchers are focused on gathering as much information as they can while they're in Hawai'i.

By the end of the first day, the ROV was sending back consistent readings.

"We'll probably have to make some adjustments," Johnson said. "But it looks like it will work. Right now, I'm optimistic."

Dan Nakaso can be reached by phone at 525-8085, or by e-mail at dnakaso@honoluluadvertiser.com