Monday, August 1, 2016

CSS Georgia, H.L. Hunley and USS Monitor conservators detail challenges, rewards

Will Hoffman details USS Monitor's remarkable engine

One was reduced to salvage items. Another was a traditional shipwreck. And the third came up largely in one piece, its contents a time capsule of innovative naval warfare.

The discovery and recovery of Civil War wrecks are a blink of the eye compared to their cleaning and the decades it takes to conserve items as large as a turret or as small as matchstick.

The complexity, cost and challenges of conservation was the subject of the “Wrecks, Recovery & Conservation” symposium held Saturday (July 30) at the National Civil War Naval Museum in Columbus, Ga. The speakers featured preeminent conservation experts who have been tasked with helping bring the stories of the CSS Georgia, USS Monitor and the H.L. Hunley to the public.

“What is the long-term process of bringing these articles to life to us?” Jeff Seymour, director of history and education at the Columbus museum, asked before the conservators spoke to 25 patrons who listened closely and viewed PowerPoint slides.

It starts with patience. Conservation can take decades. 

CSS GEORGIA: Working with salvage

Seymour called the Confederate ironclad scuttled in Savannah, Ga., “the hot recovery topic right now.”

Filmmaker Michael Jordan, who is producing a documentary, highlighted three aspects: Ordinary people doing extraordinary things (22 Savannah women raised the equivalent of $2.6 million to build the boat), failure sometimes being good (while it was too underpowered to engage in battle, the CSS Georgia was a strong deterrent as a floating battery), and being forgotten is the best way to being saved.


Jim Jobling (above), chief conservator on the CSS Georgia, provided details of the unique condition of the boat, which is being moved as part of a channel deepening project at the busy port. It was salvaged a couple times after the war. Buoys and dredges caused damage in the decades since and a swift current makes recovery difficult.

“We are not dealing with a wreck,” he told the audience. “What we have is a salvage dump site.”

While the Savannah River is only 42 feet deep, visibility for divers often is negligible. An array of technology and voice commands led Navy and U.S. Army Corps of Engineers contract divers to artifacts.

“This is archaeology by Braille, but we have a positioning system,” said Jobling. The location of items is recorded and the divers work in 10-foot squares. (A large portion of the CSS Georgia was brought up in 2015, but crews are returning in 2017 to bring up the east casemate. Numerous attempts were made to bring it up, but there was not enough support beneath the artifact. Iron beams will be used.)

Several of these were found in the wreckage

Another challenge was building trust and sharing skills with the U.S. Navy salvage team that brought up larger items, include a propeller and several guns. (That group also provided brute strength: One Navy diver carried two Brooke gun bolts totaling 180 pounds to a basket.). “Once they learned the history, they became part of it,” Jobling said.

Before he traveled from the conservation lab at Texas A&M University, Jobling believed the recovery would yield 35 tons of material. Jobling shipped 140 tons (15,500 artifacts) in numerous two-day shipments.

Twenty-four tanks are involved in the process, and hundreds of artifacts currently are being rinsed to remove chlorides. “We have only started the conservation process,” which could last 10 years.

USS MONITOR -- Understanding your artifacts

Chief conservator Will Hoffman, who works at the USS Monitor Center at the Mariners’ Museum in Newport News, Va., spent a good amount of his talk describing the science and techniques of conservation once items are in the lab.

Will Hoffman
He described forces that cause corrosion and technology that can combat further damage.

Iron can become very brittle after years of exposure to ocean chlorides. Hoffman said it very important to know the materials they are working with before attempting to take items apart for further cleaning. “You only get one shot at it.”

When building a conservation plan, Hoffman said, it is important to know three things about an artifact: How was it made? How was it used? How has it degraded?

Experts often work first on smaller pieces to refine techniques. Sometimes it can take months to build a rig that can eliminate concretion (hardened layers of sand and shell) fixed on an item, he said. “I have to do this step to do this step before I take it apart.”

The work, which follows a protocol, is painstaking. For example, 10 tons of concretion were removed from the Monitor’s remarkable engine.

View of the engine (Courtesy: The Mariners' Museum and Park)
Reverse osmosis tanks (Courtesy: The Mariners' Museum and Park)

A reverse osmosis water filtering system installed in 2010 has assisted conservators, as well as detailed schematic drawings for the ironclad, which fought the Merrimack at the Battle of Hampton Roads in March 1862 and sank while being towed at the end of that year.

Those working on the CSS Georgia, by contrast, are stymied by the fact no blueprint or plans are known to have survived.

Adding to the complexity of the Monitor project was the recovery of the remains of two sailors found in the signature revolving turret.

Despite facial reconstructions and the study of their DNA, no formal identities have been made. They were buried at Arlington National Cemetery in 2013. “It was a beautiful ceremony,” Hoffman said.

Personal items belonging to the pair are being held in case confirmed descendants step forward.

H.L. HUNLEY: Coming to life

Paul Mardikian with Jeff Seymour

Senior conservator Paul Mardikian, who previously did conservation work on the CSS Alabama, lost off Cherbourg, France, provided an overview of that shipwreck and the Confederate submarine H.L. Hunley.

The Hunley, which was the first combat submarine to sink a ship, was lifted out of Charleston Harbor in August 2000.

The conservation team was among the first to use digital scanning. Ten tons of sediment from were removed and the iron vessel has been through electrolysis and several chemical solutions to help loosen the concretion.

Conservators, because of the toxic environment, wear special masks and protective gear when working during the day (the tank refills at night). Adding to worries was spilled mercury from the boat’s depth gauge. Experts must be careful with the pneumatic drills that chip away at concretion.

Cleaning of exterior (Friends of the Hunley)

They had to take extreme care: The bodies of the eight crew members who died after the sinking of the USS Housatonic were inside. “This is a grave, a battle site, a crime scene,” Mardikian said. “You have tangible human remains.” X-rays could damage remaining DNA.

“It is relatively rare to find human remains,” said Mardikian. Among his duties, beyond studying them, was to ensure the remains would not decay before their 2004 burial.
“Saltwater is good for (preservation of) human remains, bad for (metal) corrosion, he said.

The scientists had to create their own conservation plan and techniques for such a unique scenario. And there were surprises: Among them, no gun was found inside, but a matchstick was. “They are the most ephemeral objects to conserve,” Mardikian said of an item likely used to light a smoker’s pipe or a lantern.

Remnants of clothing fabric had the consistency of toilet paper. Cashmere and silk, he said, are among the most durable. In the realm of you get what you pay for, the artifacts made of the highest quality have proven to be the easiest to conserve. The famous lantern, he said, was made of inexpensive tin.

Over the 16 years, there have been occasional setbacks: Erratic funding, delays and drainage problems with the conservation tank. It’s a 10-20 year process, Mardikian said.

A view of the July 30 symposium in Columbus, Ga.

But there have been huge rewards. Deconcretion of the submarine’s exterior and interior have brought the warship to life. “When you look at the sub design, it is splendid. It is like looking at the sub for the first time,” Mardikain said.

“The cast iron is very beautiful. You want to kiss it. But it is very corroded.”

As he continues to guide conservation work on the Hunley at Clemson University’s Warren Lasch Conservation Center in North Charleston, S.C., Mardikian does other work with his company, Terra Mare Conservation.

One project was working with a venture by Amazon CEO Jeff Bezos to conserve a Saturn V rocket engine that propelled Apollo 11 to the moon in 1969.

Apollo 11 astronaut Buzz Aldrin told Mardikian he was fortunate to work on such an array of projects: The slow, hand-cranked Hunley and the most-powerful liquid-fueled engine.

LATER THIS WEEK: Remaining mysteries

No comments:

Post a Comment