Science Serves Safety in Remediation

Science Serves Safety in Remediation

Unexploded ordinance being sifted out of a 34,000 cubic foot pile of soil. The entire operation takes place under a custom-designed building made of Kevlar® brand fiber that can be moved more than 1,000 feet along rails.

A massive building made with DuPont™ Kevlar® brand fiber sits on tracks. It is rolled slowly across a mammoth pile of soil, 50 feet high and the length of three football fields (360 feet or 109.73 meters). Under the building, remote-controlled robotic shovels loaded 34,000 cubic yards of soil onto conveyor belts where magnetic separators removed unexploded ordinance (UXO) for safe, controlled detonation at another location. 

That scene did not take place in a science fiction movie or at an abandoned minefield.  It all happened in residential Connecticut, where the DuPont Corporate Remediation Group (CRG) put safety first and the power of “One DuPont” to work cleaning up UXO at a former Remington Arms site.

“We don’t know of anyone who has done this before,” said Tom Stilley, remediation project director at the Lake Success Business Park, a 422-acre property straddling the city of Bridgeport and the town of Stratford, Conn. (U.S.)

“Most people just use UXO technicians and do it manually,” Tom said. “We made a decision early on that we weren’t going to expose workers or the public to potential hazards.”

CRG launched the UXO project in July 2008 and brought it to a safe, successful conclusion earlier this year.  While most components of the robotic shell-clearing system are commonly used in environmental remediation, “combining them this way is unique,” Tom said.  The shrapnel-resistant building of Kevlar® brand fiber, for example, was an innovation.

From 1905 until 1989, Remington used the Lake Success property to manufacture and test large- and small-caliber ammunition.  DuPont owned Remington for 60 years (1933-1993), but retained the site after selling the company in 1993.

“We knew what sort of munitions the plant had made, so we were able to conduct tests to determine fragment size and explosive force,” Tom said.  “We tested Kevlar® [brand fiber] in that type of situation and determined how thick the fabric had to be to make sure flak from an exploding shell didn’t blast through and go offsite.”

Now that most of the soil has been successfully cleared, Tom and his team will direct their efforts to removing UXO from a small lake at the site. CRG estimates that most of the Lake Success site – one of the largest undeveloped parcels in coastal Connecticut – will be ready for productive reuse in about five years.

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