KENNEWICK, Wash. — The case against a Prosser farmer accused of failing to properly store hazardous waste, which ended up severely burning three men, was dismissed Thursday morning because he suffers from dementia.

Philip Andrew Whitney, 79, was charged in Benton County Superior Court with violating the Hazardous Waste Management Act, a felony.

His case was put on hold in June so he could be evaluated by state mental health experts.

Kennewick lawyer Jim Egan had earlier told the court that Whitney was evaluated by doctors at Virginia Mason Hospital in Seattle, as well as a private psychologist, and suffers from both long- and short-term memory loss.

On Thursday, Deputy Prosecutor Terry Bloor said the Eastern State Hospital report confirmed a diagnosis of dementia. The dismissal is based on that finding, he said.

According to court documents, Whitney had improperly stored tons of fruit pomace — the remains of fruit after it has been pressed — in large pits on his property.

Benton County Fire District No. 3 described the pits as “eternal burning pulp,” with temperatures up to 500 degrees, documents said. The pits were covered with soil that allowed them to blend in with the surrounding terrain.

Three men fell into the pits between 1996 and 2011, suffering amputations and severe burns. They all sued Whitney, as well as Seneca Foods Corporation and Milne Fruit Products Inc. — companies Whitney contracted with to haul away and dispose of industrial quantities of waste.

In 1996, 16-year-old Phillip Hickle had both legs amputated after falling into one of the pits while quail hunting on Whitney’s property. Hickle settled with Whitney for $1 million and both fruit producers for an undisclosed amount in 2003, three years before Hickle died.

Jon LeClaire also fell into one of the pits in 1996, suffering second-and-third-degree burns. But his case against Whitney and the fruit processors was dismissed after it was determined that LeClaire was trespassing.

An Environmental Protection Agency investigation began shortly after Benjamin Fox fell into one of the pits in 2011 and had 11 skin grafts for third-degree burns.

Whitney sold the property to Volpe Vineyards LLC, which includes members of the Fox family, in 2010. In his lawsuit, Fox claimed that Whitney did not disclose the existence of the waste pits before the sale.

The EPA found three pits on the farm, two that were about 20 feet deep and a third that was four feet deep, court documents said. The investigation found a “fine dust-like material” in the deeper pits, with temperatures ranging from 800 to 1,100 degrees, documents said.