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PHILADELPHIA (CBS/AP) – A trial is getting under way in federal court to determine the dollar amount two vessel operators may have to pay following a collision of a tugboat-guided barge and a sightseeing boat two years ago in Philadelphia that left two Hungarian students dead.

Szabolcs Prem, 20, and Dora Schwendtner, 16, whose group was visiting the US through a church exchange program, drowned when their amphibious tour boat capsized and sank after being struck by an empty sludge barge in the Delaware River on July 7, 2010.

“We don’t really have any more holidays. We don’t have any Christmas. We don’t have anything anymore,” said Szabolcs Prem’s mother, Maria, through a translator.

The families have filed wrongful death lawsuits against K-Sea Transportation of East Brunswick, NJ, which operated the tugboat guiding the barge upriver; Ride the Ducks of Norcross, Ga., which operated the tour boat; the City of Philadelphia, which owned the barge; and others.

Before the wrongful death lawsuit may proceed, however, a judge must decide whether a limit should be set on the financial liability of the two boat owners.

K-Sea and Ride the Ducks, citing an 1851 maritime law, want the judge to cap their financial liability based on the value of their own vessels involved in the crash: $1.65 million for the tug and $150,000 for the duck boat, said Robert Mongeluzzi, an attorney representing the victims’ families.

“They’re saying to these parents, ‘The lives of your two only children are worth $1.8 million, the same as our vessels,'” he said.

“To say that my son’s life is worth the value of a ship — it doesn’t make any sense,” said Maria Prem through an attorney. “You can build another ship. I can’t have another Szabolcs.”

A Ride the Ducks spokesman said the company does not comment on pending litigation.  A K-Sea spokesman did not respond to a message seeking comment.

The parents of the victims, who are from a small city in northwestern Hungary bordering Austria and Slovakia, were in Philadelphia for opening statements of the non-jury trial, which is expected to last about a month.

“Drowning is a slow and painful death and in the final moments you know you’re going to die,” said Peter Ronai, another attorney for the families. “For parents to know how their children suffered, they’ve been living a nightmare.”

The tug pushed the 250-foot-long barge into and over the 33-foot-long duck boat as it sat idle and anchored in the active shipping lane, sending all 35 passengers and two crew members into the fast-moving river about 150 feet from the Philadelphia shoreline.

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Survivors were pulled from the murky water by firefighters, a passing ferry boat, and bystanders who swam from shore.

The victims’ bodies were recovered two days after the crash: Schwendtner was found more than a mile downriver and Prem surfaced when the duck boat was being pulled from the river bottom by a salvage barge.

The Limitation of Liability Act can be applied in accidents involving casualties when the ship owner can prove it was unaware of a problem beforehand.

Attorneys for the plaintiffs were expected to argue that was not the case, and errors by the duck boat pilot and the tug pilot, as well as insufficient training procedures and inadequate safety policies of their respective employers, all were factors in the crash.

“This accident wasn’t a freak occurrence, it wasn’t an aberration,” Mongeluzzi said. “It has its roots going back over years.”

In its 4,400-page report on the crash, the National Transportation Safety Board said the duck boat overheated on the 103-degree day because a mechanic neglected to replace a radiator cap after an inspection the night before.  The next day, the duck boat captain mistook the steam for an engine fire and shut down the vessel in the busy shipping channel, where it was hit minutes later.

Co-counsel Andrew Duffy said the team plans to present evidence that the duck boat lacked an adequate emergency air horn and radio and was designed with overhead canopies that trapped the two victims underwater when the boat capsized.  They also contend that passengers were not instructed to put on life preservers until moments before the collision, when it was too late.

They also contend that K-Sea, the tug operator, long knew its policies barring cellphone use on duty were routinely ignored yet failed to take corrective action.

In November, tug pilot Matthew Devlin of Catskill, NY, was sentenced to a year in prison after pleading guilty to the maritime equivalent of an involuntary manslaughter charge (see related story).  Prosecutors said he was on his cellphone amid a family emergency, moved to a part of the tug that blocked his view of the river, and turned down a marine radio, stifling mayday calls before the collision.

Ride the Ducks offers tours in Philadelphia; San Francisco; Branson, Mo.; Stone Mountain, Ga.; and the Cincinnati area. The company suspended its Philadelphia tours after the accident but resumed them the following spring with a shortened water route.

At about 1pm Sunday afternoon, a Duck Boat stalled on the Delaware River and was later towed safely to shore. Twenty-six passengers were on board along with two crew members. Ride The Ducks released a statement Sunday, saying in part:

“Our safety procedures worked just as they had been planned and practiced. At no time were passengers in harm’s way. It’s too early to know the exact cause of the stall. A review will be done to determine the cause of the service disruption.”

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