Thousands of communities struggle to keep their groundwater clean of toxics like TCE. It’s an expensive problem but, as Wynn Tucker reports, scientists have found a cheap solution - candles.
GELLERMAN: It’s Living on Earth, I'm Bruce Gellerman. Coming up - a teenager tries a new tactic to force the government to take action on climate change: he’s suing. But first here’s Wynn Tucker with this Note on Emerging Science.
[SCIENCE NOTE THEME]
TUCKER: Candles can be festive, somber, or useful. Now researchers have a new use for them: to clean up groundwater. Thousands of landfills and factories across the country leak toxic solvents into groundwater. One of the most common toxics is trichloroethylene, or TCE.
To clean up TCE, scientists inject the chemical compound potassium permanganate into the ground. The method is effective but expensive and labor-intensive. Researchers at the University of Nebraska have found a much cheaper solution: they’re putting potassium permanganate in candles - three-foot long wax cylinders that are then buried in the ground. As groundwater flows past these candles, the wax cylinders slowly release the chemical permanganate that breaks TCE down into harmless materials.
And the wax prevents water from entering the cylinder and keeps the chemical from dissolving all at once, evenly distributing the chemical throughout an aquifer. These candles may take a long time to work their magic, but initial results show they can effectively clean up groundwater at a low price. That’s this week’s Note on Emerging Science, I’m Wynn Tucker.
Living on Earth wants to hear from you!
P.O. Box 990007
Boston, MA, USA 02199
Donate to Living on Earth!
Living on Earth is an independent media program and relies entirely on contributions from listeners and institutions supporting public service. Please donate now to preserve an independent environmental voice.
Major funding for Living on Earth is provided by the National Science Foundation.
Kendeda Fund, furthering the values that contribute to a healthy planet.
The Grantham Foundation for the Protection of the Environment: Committed to protecting and improving the health of the global environment.
Contribute to Living on Earth and receive, as our gift to you, an autographed copy of one of Mark Seth Lender's extraordinary hummingbird photographs. Follow the link to see Mark's current collection of photographs.