NORTH CHARLESTON — The submarine H.L. Hunley sits in a tall, blue tank at the Warren Lasch Conservation Lab, filled with 45-degree water pumped in from the public water system.

No chemical soup. No scientific improvisation. No radical experimentation. Just tap water.

Chemicals would have spoiled the remains of the Hunley crew. Experimentation could threaten the physical integrity of the historic vessel. So, for now, scientists want to keep it simple.

“You don’t want to do any ‘kitchen sink’ work here,” said the Hunley’s senior conservator, Paul Mardikian. “You don’t want to guess.”

When the Confederate pomp and circumstance of today’s burial for the Hunley crew is over, what will remain will be the sub and the science.

Preserving the 40-foot-sub is a challenge. Salt from 140 years of sitting on the bottom of Charleston Harbor would slowly turn its cast iron frame into rust if exposed to air. The chlorides must be removed for the boat to be stabilized.

In the past, the only way to save such vessels from the ravages of the sea was to disassemble them. Salt can effectively be removed from individual pieces of metal by electrolysis. But removing it from between riveted plates, or the intricate working of machinery, has been difficult, if not impossible.

Disassembling the Hunley would require drilling out dozens of rivets from its fragile metal plates and wrenching apart its delicate moving parts. The cure could be worse than the disease.

“The question is whether you can put it back together again,” said Michael Drews, a professor of material science and engineering at Clemson University.

Hunley scientists say they are developing a groundbreaking technique for removing the salts from the metal. But the method — which involves a process called cold hydrogen plasma reduction — is unpatented and uncertain.

“We’re still working on a solution,” Drews said. “We’ll find out 15 to 20 years down the road if we made a mistake.”

For now, they are tight-lipped on the details.

“The intellectual property isn’t protected yet,” Drews said.

The lab usually is only open on the weekends for tours. Visitors watch videos about the ship’s recovery and conservation, see scientists at work and view the boat itself.

But with about 20,000 people in town for today’s burial, the lab has been open every day.

Up to 300 visitors have filed past the Hunley daily, paying $10 to see the first submarine to sink an enemy ship in combat. Most also spend at least that much in the lab’s gift shop.

Hunley boosters and backers hope the stream of visitors continues as more people learn about the project from today’s national press coverage of the burial.

The sub is to be the centerpiece of a planned $40 million Hunley Maritime Center to be built in North Charleston. The advancement of the museum, as well as the advancement of science, depends on the Hunley surviving its recovery.

The sub could be left soaking in a tank, but that would lessen the visitors’ experience. The scientists’ aim is to stabilize the sub so it can be displayed in open air.

But marketing is not their first concern. The Hunley team’s goal is find a way to conserve not only their boat, but other maritime treasures as well.

“Our job is to preserve things that were not meant to last forever,” Mardikian said.

Reach Wilkinson at (803) 771-8495 or jwilkinson@thestate.com