A phosphorous fire broke out on the Stauffer Chemical Superfund site Wednesday evening, sending a large plume of white smoke into the air until the blaze burned itself out after more than two hours.
City fire officials said the fumes from the blaze never reached hazardous levels, and they did not notify nearby residents.
The fire started shortly before 6 p.m. as crews testing the soil drilled into a large pocket of white phosphorous, which spontaneously ignites when exposed to air.
A crew from Envirocon, the company hired by Stauffer to clean up the site, tried to smother the flames with sand and water. Workers called 911 when they were unsuccessful, said Tarpon Springs fire Chief Kevin Bowman.
Several firetrucks and hazardous materials units responded and stood by in case the fire escalated or release of chemicals approached harmful levels, Bowman said.
Envirocon officials, meanwhile, surrounded the fire with piles of soil and held down vapors with water, Bowman said. The fire burned itself out at 8:20 p.m.
The fire was not unexpected. Drilling into the contaminated soil often sparks small fires, which crews are normally able to extinguish with water trucks and earth-moving machines.
The drilling is a precursor to the project, termed a "mound and cap remediation plan."
Now, Stauffer is testing to find the ideal recipe for the concrete that will be pumped into the ground to stabilize the phosphorus. The actual remediation is scheduled to begin sometime this summer.
"This is more of a visual effect, then a concern event," said Tarpon Springs fire Capt. Don Sayre. "It has not affected any residents."
The more recent significant fire at the site was in October 1996. Workers were trying to take 50,000 gallons of crude phosphorus from the site when some of it caught fire and sent irritating smoke into nearby neighborhoods. The removal was delayed until the summer of 1997. The old plant, which processed phosphate ore into elemental phosphorus from 1947 to 1981, left soil contaminated with more than 30 hazardous materials.
Residents petitioned to have the contaminated soil excavated and shipped from the heavily populated area. But under the remediation plan, the tainted soil will be left on site, and mixed with cement. Once it is stabilized, a watertight cap will be placed on top to prevent water from washing chemicals into the groundwater below, company officials said.
A layer of claylike sand or sandy clay below the contamination also is expected to prevent groundwater from seeping into the deep aquifer.
The cleanup plan continues to fuel longstanding suspicions. Residents have questioned what portion of the 130-acre site really needs to be cleaned up, which contaminants are being targeted and how long the solution is expected to last.