Associated Press
Cody Emerine surveys some of the destruction after a wildfire swept through the Oaker Hills neighborhood in June.

More than 100 property owners sued Utah's largest utility for negligence Tuesday after a summer wildfire burned more than 70 square miles and destroyed more than 50 homes.

The group of cabin owners, landowners and business interests filed the lawsuit against Rocky Mountain Power after authorities determined the blaze — which left one man dead — was caused by arcing between two sets of power transmission lines built too closely together.

The family of the man who was trapped and killed by the fire is reportedly pursuing a separate legal claim.

The utility initially blamed a thief for stripping a protective copper ground wire from one of its transmission poles. But a state fire investigator later determined the ground wire wasn't designed to absorb the powerful arc and wouldn't have stopped the surge from igniting dry grass.

Rocky Mountain Power said Tuesday it is offering cash settlements to landowners. In a statement offered to The Associated Press, the utility was careful to avoid admitting fault but said it was pursuing out-of-court settlements with dozens of families.

"We believe this lawsuit is unnecessary, given the company's initiation of a claims resolution process," Rocky Mountain Power spokeswoman Maria O'Mara said.

The utility says it has already paid some settlements. Rocky Mountain Power President Richard Walje made the offer at a July 31 meeting in Fairview with hundreds of fire victims.

"Until liability can be determined, based on preliminary information, I decided that we should try to help by making it easier for individuals who experienced losses from the fire to rebuild their homes and structures," Walje told the crowd, according to a statement provided by O'Mara. "I'm here to propose a process to assist you in that effort."

But one of the lawyers involved in the case, Jonathan Schofield, said Rocky Mountain Power may be shortchanging landowners who decided not to sign up for the lawsuit.

"We just want to make sure our clients are adequately compensated for their losses," Schofield said. "It's unclear whether Rocky Mountain Power is considering the full extent of damages that have been incurred for the fire victims."

The lawsuit doesn't specify how much money the plaintiffs seek. It represents owners of more than half of the 54 square miles of private land that burned, said Stephen J. Hill, another lawyer. Another 17 square miles of public range land were blackened.

Among the 104 plaintiffs are cattle ranchers who had to sell herds because of the loss of forage, Schofield said. Others are residents of several wooded subdivisions around Indianola off Utah's scenic Route 89.

The Wood Hollow Fire started June 23 about 15 miles farther south, near Fountain Green. The blaze was one of Utah's largest this year, destroying 52 houses and more than 100 outbuildings. It took 10 days to fully contain and cost the state more than $5 million to fight, officials said.

Winds caused two sets of high-voltage power lines to either touch or swing close enough to each other to create a surge that swept down the poles into dry brush, Deputy Utah Fire Marshal Troy Mills found.

"That is the cause of the fire," Mills told the AP in July. "There's some things where you've got to take a stand. It is what it is."

Lawyers in the case say the arc also could have flung a piece of molten metal onto dry grass.

O'Mara said Rocky Mountain Power is conducting its own investigation into the fire and will share the results once the probe is completed.