Gowanus Canal In Final Stage Of Pilot Cleanup: EPA

GOWANUS, NY — The Environmental Protection Agency is nearing the completion of a pilot project that has scooped 17,000 cubic yards of toxic muck from the Gowanus Canal to inform the waterway's federal cleanup.

Officials gathered at the Fourth Street Turning Basin in Gowanus Monday to discuss the agency's progress overcoming engineering challenges during the pilot as the EPA prepares to clean the rest of the 1.8-mile long Superfund site.

“This pilot project is serving its purpose: to show us what works best and what may not work as well under real-world conditions as we move toward full-scale cleanup of this highly-contaminated canal," said Pete Lopez, the EPA's regional administrator.

A major lesson learned during the pilot project was how to install metal bulkheads along the canal's banks. At first, the method for driving the metal sheets into the ground too violently shook the earth, creating fissures in nearby properties, which caused months of delays.

The Whole Foods, part of which runs along the Fourth Street Turning Basin, began sinking toward the Gowanus Canal after equipment forcefully shook the ground and ruptured the soil beneath. Since then the Environmental Protection Agency has modified its bulkhead installation to rely less of vibration and more on compression, explained an agency official.

“We ended up directing the company that’s doing the work to use a different technique which hydraulically presses the pile down into the ground," said Walter Mugdan. "So rather than pounding it or vibrating it, it simply presses it and that has the least amount of impact to the surrounding area."

After bulkheads were installed the dredging removed roughly 11 feet deep of toxic sludge known as black mayonnaise at the bottom of the canal. Officials used the sediment to cover landfills in Pennsylvania and hunks containing too much liquid tar were sent to facilities in New Jersey and burned away.

The final portion of the pilot will be a process known as capping that will lay two feet of sand, clay and other granular materials to prevent contaminants from migrating up into the water. The pilot began in October and officials except to complete the project this fall.

Dredging on the remainder of the canal is anticipated to begin in 2020 and the entire cleanup is expected to wrap up around 2027.

Lead photo by Drew Angerer/Getty Images. Photo of Whole Foods sinking towards the Gowanus Canal courtesy of Caroline Spivack/Patch.