Tue May 14, 2013
Lees Lane Landfill Soil Testing Shows Contamination, But Source and Scope Still Unknown
New soil sampling at the Lees Lane Landfill shows there’s still some contamination at the site, but further testing is needed to determine whether the heavy metals and toxic chemicals found in the tests originated at the landfill.
The landfill was a sand and gravel pit that became the repository for 35 years worth of household trash, industrial waste and toxic chemicals. It was closed in the 1970s, after methane gas began migrating from the landfill and caused flash fires around hot water heaters in some of the homes near the site. It was on the nation’s Superfund list—a catalog of hazardous waste sites in the most need of cleanup—from 1983 to 1996, while federal, state and local regulators attempted to remediate the site.
The landfill is sandwiched in between the river and the Riverside Gardens subdivision in Southwest Louisville, and local residents have long suspected the site has contributed to health and environment problems in the community. The landfill is technically off-limits, but there are signs of people trespassing on ATVs and motorcycles.
Testing shows signs of heavy metals, chemicals
Last month, crews from the Kentucky Division of Waste Management took 40 soil samples at the landfill in an attempt to determine whether the site poses a danger to people who frequently trespass on the site and might come into contact with the soil. Though the state will prepare a more in-depth report in the coming weeks, the initial analysis suggests there are still high levels of certain chemicals, and more testing is needed.
Many of the samples contained high levels of heavy metals like arsenic, lead and iron. In one sample, the amount of arsenic in the sample was 20 times higher than the federal screening threshold. Arsenic is listed as a chemical of concern (along with benzene, lead, and chromium) at the site by the Environmental Protection Agency.
But there were other things, too, like semi-volatile organic compounds. Large amounts of benzo(a)pyrene were present in more than half of the samples…in one case, exceeding the federal screening threshold by 340 times. Some samples also showed elevated levels of pesticides and PCBs. All of these chemicals mean the site could still pose a risk to people who trespass and come into contact with the soil, and the landfill likely isn't ready to be used for legal recreational use.
Source of chemicals could be the landfill or nearby industry, traffic
Russ Barnett of the University of Louisville wasn’t involved in the soil sampling, but has spent years conducting environmental tests in Louisville. Looking at the data, he says the biggest obstacle is figuring out where these contaminants come from. The arsenic and benzo(a)pyrene could have come from vehicle traffic, or from the nearby coal-fired Cane Run power plant. Barnett said he hadn’t heard of pesticides discarded in the landfill, but those could have been intentionally added to the site during landscaping in the 1980s. Other chemicals could have gotten into the soil from flooding, though Barnett says that doesn’t seem likely, because that would probably result in uniform levels at every sampling site.
Barnett says one of the logical follow-up tests would be soil sampling near the landfill.
“What you have to keep in mind is that unless you have samples off-site, so that we kind of know what the background levels might be, you can’t really say that any of these have anything to do with the landfill,” he said.
Regardless, Barnett says these most recent testing results suggest there are valid concerns about some chemicals at the landfill, especially arsenic and benzo(a)pyrene. He says it doesn’t seem to pose an imminent risk, but the site isn’t ready to be turned into a park or soccer fields, as was once suggested by Metropolitan Sewer District officials.
“I wouldn’t characterize this site as being hazardous to the community,” he said. “But what it does tell you is that the whole idea of turning this over to a recreational site, we aren’t there yet either until we get a better handle on exactly what the hazards are out here.”
Tim Hubbard with the Kentucky Division of Waste Management declined to comment for this story, saying he would wait until state regulators finish their analysis of the data. But he notes that finding the chemicals doesn’t necessarily mean action is required; the results could be statistically insignificant, or similar to background levels. The state plans to release its report in the next two weeks.