The Raytheon Company said it has just won state approval to begin vaporizing a toxic waste plume that first polluted the groundwater under a former defense plant located in St. Petersburg two decades ago.
"Today is a really big day for us," said Raytheon site executive Mitch Lee. "We're going right at the source, and in less than a year we'll eliminate 90 percent."
The so-called thermal remediation uses a network of 500 wells drilled under the now-vacant defense manufacturing center in the Azalea neighborhood on 72nd Street North.
Each well is equipped with a heating element designed to boil the groundwater 40-60 feet under the surface. The point is to vaporize chemicals dumped there decades ago by a previous company and then extract and neutralize the vapors through an elaborate network of pipes and scrubbing devices.
"That's the best way to get those chemicals up and out of the ground," said Lee.
It's also one of the most expensive.
Lee estimated the thermal heating process will cost Raytheon $20 million and said it is just part of a process to clean the toxic plume that has spread through groundwater more than half a mile from the plant, under surrounding homes parks and playgrounds.
Four years ago, News Channel 8 revealed the existence of the plume, which Raytheon and the Florida Department of Environmental Protection had known about for 17 years.
After News Channel 8 started testing, Raytheon did its own studies and discovered dozens of nearby private irrigation wells had been contaminated by chemicals in the plume. State health authorities later determined no one was at risk as long as no one drank the water.
The spread of the plume angered neighbors and sparked a class action lawsuit that eventually fizzled in federal court.
Friday, Raytheon gave St. Petersburg Mayor Bill Foster a private tour of the plant and the elaborate thermal system it will soon start using to cleanse the groundwater.
"My initial response was, 'Wow,' " said Foster. You will be amazed. This is not your typical Stanley Steemer."
For several months, Raytheon has been pumping an oxidizing chemical — sodium permanganate — under Azalea Park to help break down vinyl chloride, TCE, 1,4, Dioxane and other toxic chemicals that have spread under the neighborhood.
"It essentially breaks down the contaminants into their basic elements of hydrogen and carbon dioxide," Lee said.
The company has also constructed a system of 11 wells in nearby residential neighborhoods connected by a system of pipes that will be used to pump and treat other waste.
If all goes as planned, Lee says the neighborhood should see relief within five or 10 years instead of the 78 years Raytheon told the state it would take to finish the job.
"We expect a lot better and a lot faster results," Lee said.
Azalea Neighborhood Association President Dominick Griesi was one of Raytheon's biggest critics when news of the plume became public. But Griesi said Raytheon has come a long way toward mending fences with the neighborhood, frequently attending community meeting with updates on the remediation process.
After the federal class-action suit fell apart, Raytheon also became generous.
The company donated $100,000 for improvements to a recreation building in Azalea Park across the street from its plant and has given as much as $2,500 each to more than 250 home and condominium owners to help pay for landscaping and home improvements.
They received the money under the condition that they sign contracts agreeing not to sue Raytheon over the pollution issue.
The next test will be at the end of the month after Raytheon completes its pump and treat system in the neighborhood and activates that phase of the cleanup.
"There's no impact expected as far as noise or disruption," Lee said.
And so far, no complaints, according to Griesi.