Federal regulators are about to bury a mile-long wall deep underneath one of Gainesville's most contaminated properties. The U.S. Environmental Protection Agency plans to construct a 65-foot-deep underground barrier beneath four contaminated areas of the Koppers Superfund site, designed to trap polluted groundwater within the property's boundaries before it can spread any further.
The plan, first detailed by Mainstreet Daily News Gainesville, calls for the wall to cut through multiple aquifers and anchor into a clay bottom, then be capped to keep rainwater from seeping in or overflowing. Once finished, the structure won't be visible from the surface at all. EPA site manager Megan Arias presented the plan to the Gainesville City Commission, according to the same report, and construction is slated to begin this fall and run until June or July of 2027.
The 90-acre Koppers site sits at 200 NW 23rd Avenue, north of the avenue and west of N. Main Street, where wood-preserving operations ran continuously from 1916 until 2009. According to the Florida Department of Health, the facility used heavy chemical preservers including creosote, pentachlorophenol, and chromated copper arsenate for 93 years before shutting down for good.
Decades of Contamination Reaching the Aquifer
The EPA placed the Cabot Carbon/Koppers site on the National Priorities List in September 1984 after decades of unlined waste lagoon disposal left widespread soil and groundwater contamination, per the agency's own case summary. Hydrogeologic studies later found that creosote-derived dense non-aqueous phase liquids and dissolved pollutants had penetrated more than 150 to 200 feet beneath the Koppers property, according to research from GeoHydro Consultants — a depth earlier 1990 EPA cleanup models failed to detect.
That migration matters because the site sits roughly two miles southwest of Gainesville Regional Utilities' Murphree Wellfield, which draws municipal drinking water from the Floridan Aquifer for more than 135,000 local residents, The Oracle reported. Preventing creosote DNAPLs, dioxins, and heavy metals from reaching that water supply has been the project's central technical hurdle for years.
Nearby neighbors should expect tree removal and heavy machinery activity as crews prepare the site, Mainstreet Daily News Gainesville reported. The EPA is also monitoring groundwater at the property's borders to catch any runoff, and the agency says the wall itself is expected to stay in place permanently — Arias said it is not expected to be removed and the site will not return to an unrestricted condition.
A Ditch Relocation Finally Resolved
Subsurface containment work had stalled for years over a regulatory deadlock about relocating a drainage ditch that cuts through the property and empties into nearby Springstead Creek. In September, Florida state environmental regulators prepared to renew the site's stormwater permit after that dispute was resolved, according to WUFT News. That breakthrough is what cleared the way for this fall's slurry wall construction, the station reported.
It isn't the first time work at the site has stirred up trouble for neighbors. During preliminary slurry wall preparation on the adjacent Cabot side in 2019, excavation of deep pine-tar deposits triggered widespread odor complaints from businesses along Northwest 23rd Avenue, as digging exposed historically trapped volatile pine tar, the station's report noted at the time.
Soil Removal and the Municipal Storage Yard
The broader Cabot/Koppers Superfund site includes three distinct areas: the Cabot area, the Koppers site itself, and a 37-acre municipal storage yard owned by the city of Gainesville. The Cabot area has already been cleaned up and returned to reuse, while the municipal storage yard should be fully remediated once current scheduled activity wraps up, per Mainstreet Daily News Gainesville.
As part of that work, the EPA plans to remove soil piles and surface soil from the municipal storage yard and place that material inside the newly capped wall. Once mitigation is complete, the storage yard is expected to become available for future uses, according to the outlet's report.
Earlier cleanup milestones have already shown up in the neighboring Stephen Foster community. Beazer East Inc. completed off-site soil replacement across 100 residential properties there in November 2014, excavating up to two feet of dioxin-contaminated topsoil that had been deposited by wind-blown dust and surface runoff, according to the Alachua County Environmental Protection Department. A follow-up 2014 indoor dust study by Protect Gainesville Citizens Inc., funded through an EPA Environmental Justice grant, found that replacing that contaminated yard soil led to measurable reductions in indoor dust dioxin concentrations inside nearby homes.
Who Pays, and What Comes Next
Beazer East Inc., which owns the Koppers site and holds historical corporate liabilities tied to the old wood-treatment operations, signed a consent decree with the EPA in 2013 that requires an estimated $55 million in cleanup costs. Any future reuse of the Koppers property will be held to commercial and industrial standards only, with residential development prohibited, and the site will require additional steps before any reuse can happen.
Officials have pointed to the adjacent Cabot Carbon portion as a model of what's possible: pine-stump processing there ran from the 1910s to the 1960s before soil remediation in 1994 allowed the land to return to commercial use as a shopping center, according to GeoHydro Consultants. The Koppers site could eventually support development too, but only above the wall and several feet of clean soil, Mainstreet Daily News Gainesville reported.
The EPA will hold a community informational session on October 21 from 5 to 7 p.m. at the site, giving nearby residents a chance to ask questions directly about the construction timeline and what to expect as crews move in this fall.
