Pacific Gas & Electric — one of the nation’s largest utilities whose equipment has sparked some of California’s deadliest wildfires — wants to bury power lines in some of its most at-risk areas to prevent destructive blazes like the 2018 Paradise fire that killed 85 people.

But state regulators are balking at the utility’s plan because it would take too long and cost $5.9 billion. The company’s customers — who already have some of the highest rates in the country — would have to pay for it.

Regulators want PG&E to put a protective cover over many of its overhead power lines instead of burying them. The cover approach is cheaper, but riskier.  PG&E, which filed for bankruptcy protection in 2019 after it faced more than $30 billion in damages for wildfires started by its equipment, is trying to convince regulators that its burying plan is better. The company filed its plan with state regulators last year.