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Salvors use hot tapping to extract toxics from Lake Erie wreck

Mar 24, 2016 12:08 PM
The tug Manitou and crane barge Farrell 256 conduct anchoring operations at the Argo site near Kelleys Island in Lake Erie.

Courtesy T&T Salvage

The tug Manitou and crane barge Farrell 256 conduct anchoring operations at the Argo site near Kelleys Island in Lake Erie.

Working against the clock, salvage contractors have completed recovery of toxic cargo from a long-lost tank barge that sank in Lake Erie during a storm in 1937.

During the two-month operation, T&T Salvage extracted approximately 33,475 gallons of liquid using the “hot tapping” method. Approximately $5.2 million of the Oil Spill Liability Trust Fund and $450,000 from the hazardous material superfund was utilized during the effort. 

Members of the Cleveland Underwater Explorers (CLUE) were diving nine miles northeast of Kelleys Island, Ohio, on Oct. 23 when they noticed a solvent odor. The odor was confirmed by the Coast Guard and an overflight revealed a 400-yard area of discoloration near the site. A second flight the following day was unable to locate any discoloration and subsequent air monitoring didn’t reveal any fumes or pollution. 

Though the apparent leak had ceased, the Coast Guard decided the situation needed additional response.
 
“There was still that concern that it has leaked once before — how much more could it leak or could it leak again?” said Petty Officer 3rd Class Christopher M. Yaw.

As the only Great Lakes-based salvage and marine firefighting service provider that is also a Coast Guard-classified Oil Spill Recovery Organization, T&T was chosen for the operation.

When T&T divers arrived, they were unsure if the vessel they were dealing with was Argo — as it had never been located following its sinking — but it was suspected.

Diver Corey Lewis, wearing a protective hazmat dive suit and helmet, prepares to enter the water.

Courtesy T&T Salvage

“There was a mystery surrounding the location,” said Jim Elliott, vice president of T&T Salvage. “There were no drawings of the barge. The only information that we really had was a small newspaper article from 1937 that said there was about 100,000 gallons of cargo on board.”

The article — published Oct. 22, 1937 — indicated the barge was headed to New Jersey when it fell victim to a winter storm. It was believed to have been carrying 100,000 gallons of benzol.

As it turned out, the sunken barge, determined to be Argo, still had some of that toxic chemical in its tanks. According to Coast Guard testing, toluene, xylene and trace elements of petroleum were found in Argo’s tanks. The findings were consistent with benzol’s chemical makeup. 

The high-benzene cargo not only posed a threat to divers, but also presented an inhalation risk to responders on the surface. A safety zone with a radius of 1 nm was established by the Coast Guard and maintained during the two-month response effort. Crews on the surface worked in hazmat gear. 

Because the response project happened in late October through mid-December, there weren’t many recreational boaters on the water, said Yaw. While the timing allowed crews this silver lining, it also created obstacles. Winter weather and low visibility made things particularly challenging, according to Elliott.

“You have this pending deadline, because it continues to get colder and conditions become icy,” Elliott said. “So, ultimately, we ended up working around the clock for several days to get within these weather windows, which is not typical. It’s not typical that you’re doing these types of operations at night.” 

Crews were continuously rotated in the face of high stress, weather conditions and low visibility. 

Pumps, flanges and hot-tapping equipment used to connect the hydraulic pumping system.

Courtesy T&T Salvage

Divers conducted a hand-over-hand survey of the vessel, which was in 44 feet of water and significantly covered in marine growth. 

“You’re basically in the dark trying to do a survey of something that you don’t have a drawing for, you don’t have a photograph of,” Elliott said. “You’re trying to get a visual of what you’re dealing with.”

Because of the highly volatile cargo, divers wore fully encapsulated positive pressure systems and Desco helmets. 

“If something would happen — say they would get a cut on the suit or a rip — it would push the water out,” Elliott said. “We had to up our game when it came to the traditional commercial diving outfit.”

They had to be creative when it came to storing the cargo after it was extracted. Benzol isn’t typically shipped on the Great Lakes, and proper equipment wasn’t immediately available. A receiving barge was configured by putting six 21,000-gallon tanks on a deck barge and installing carbon filters that separated and removed flammable vapors from the product.

Using the hot-tapping method, the mixture was removed from Argo’s eight tanks by pumping hot steam into the tanks through carefully drilled holes. The oil, which flows more easily after being exposed to the steam, was then pumped to the receiving barge on the surface. Ultimately, it was discovered that two tanks held the benzol mixture, said Elliott.

During prepping for this process, a pinhole leak sprang from one of the rivet holes as marine growth was being cleared, but was patched within minutes. 
 

Salvage technicians connect discharge hoses to pump the benzene cargo into frac tanks for safe removal.

Courtesy T&T Salvage

“We had divers ready, they had their contaminated-water diving suits, (they) went down and just patched it,” Elliott said. “We had the Coast Guard monitoring everything and within minutes the air quality was within normal parameters.”

Responders on the surface who potentially could have been exposed to inhalation of the substance were examined by medical professionals and received an “all clear,” said Yaw. 

“Due to the hard work and dedication shown by all, a significant hazard to the public and the environment has been effectively mitigated,” the Unified Command said in a statement following the salvage. “In addition, the interagency cooperation shown during this response has better prepared local agencies to effectively address future problems that may arise in western Lake Erie.” 

Argo is just one of many forgotten shipwrecks that have the potential to release cargo, according to the National Oceanic and Atmospheric Administration (NOAA). In 2013, NOAA provided a report to Congress detailing 87 individual wreck assessments and their potential ecological and socio-economic impacts. Argo, included on the report, was listed as one of 40 wrecks assigned medium priority for the worst case of discharge.

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