More than 100 people heard state environmental regulators and Raytheon Co. executives detail a cleanup plan Tuesday night for a plume of pollution that has been moving beneath their neighborhood for 16 years.
Raytheon said it will take a lot longer than that to get rid of the pollution, the result of chemical dumping by a company that developed the operation decades ago.
During a community meeting at Azalea Middle School, Bob Luhrs, Raytheon's senior manager for remedial programs, said 97 percent of the chemical mass will likely be gone within three years.
But projections show it could take as long as 80 years to finish the cleanup.
"Mother Nature will tell us whether we guessed a little too long or a little too short," Luhrs told the crowd, "So I wouldn't hang my hat on the 80 years, but it will be a long period."
Homeowner Jim Schottman wanted to know whether Raytheon will stay with the project now that it has placed the shuttered defense plant at 1501 72nd St. North up for sale.
"I don't know whether we'll sell it or not, but there is a sign for sale," Luhrs responded. "I do agree to that."
The plume of industrial waste was first made public through a News Channel 8 investigation three years ago. The plume spread under parks, playgrounds and homes without the knowledge of many residents, even though the state and Raytheon have been quietly working on the problem since 1995.
Concern grew among homeowners when they learned the pollution had contaminated more than two dozen private irrigation wells near the plant. State health officials said no one was at any risk due to the low concentration of chemicals in the wells and the fact that no one drinks the water.
Still, the stigma of pollution up to half a mile from the Raytheon plant has hurt property values. Last year, Pinellas Property Appraiser Pam Dubov reduced the value of 349 parcels by 5 percent for a total reduction of $3.5 million in neighborhood home values.
At the Tuesday meeting, Raytheon explained that the cleanup will take a three-pronged approach involving pump and treat technology, thermal heating and oxidation.
A system of wells and pumps will extend into the neighborhood to extract tainted ground water but won't be noticeable after initial construction.
"Everything will be out of sight and it will be dead silent," Luhrs said.
He also discounted the idea that mass pumping will trigger sinkholes.
The thermal treatment will heat groundwater and soil under the plant to near boiling temperatures to release chemicals in a vapor state so they can be extracted and treated onsite.
Oxidation will act to break down other compounds through chemical reactions under the plant, where the highest concentration of pollutants exist.
Luhrs said a temporary pump and treat system on the Raytheon property has already extracted 28 million gallons of polluted groundwater for treatment onsite and disposal in the city sewer system.
Tom McClure, who said he has lived in the neighborhood for 30 years, questioned why the state hasn't fined Raytheon.
"That would be the only fair thing," McClure said Tuesday night. "It would be expected if it happened to me."
Others pressed Luhrs for a completion date so they can sell their properties without having to declare a pollution problem to potential buyers.
Luhrs didn't have an answer.
"All I can say is it's going to shrink," Luhrs said. "I don't have that information in front of me."
The next step in the cleanup process, the state Department of Environmental Protection, said, is state approval of the Raytheon plan.