C+S April 2021 Vol. 7 Issue 4 (web)

First, the contractors removed the contaminated paint. A hydro-blasting technique was applied that uses high pressure water to remove the paint from the concrete. The paint is then vacuumed up at the point of removal from the stack’s surface and contained in a closed system. This proce- dure minimized the release of any hazardous material and eliminated the need for workers to directly handle the contaminated waste. Next, the contractors began dismantling the stack using what is called the MANTIS Demolition System that is an unmanned -remotely oper- ated - hydraulic machine used to dismantle large chimneys. “With this system, the equipment actually sits on top of the stack and walks its way down as it chips away. Each piece of concrete is bro- ken out, the rebar supports are cut, and it all falls inside the stack for removal. By the stack collecting its own waste, it keeps workers and the surrounding area protected from hazardous material,” said Mat- thew Creamer, project manager, New York District. “The system also produces limited vibration, which protects nearby lab equipment from being damaged.” Additional safety measures are in place to protect workers and the sur- rounding environment. Water sprayers were installed on the MANTIS equipment and at the bottom of the stack to suppress dust from the concrete. In addition, air monitoring samples are being continually taken to make sure there are no contaminants in the work area, and silt fencing was set up around the work area to prevent any contaminated water from running off the site. All contaminated soil, debris and material is being removed and trans- ported to approved off-site waste disposal sites. When the project is completed, a final survey of the site will be performed, and the land will be graded with clean soil. The project is expected to be completed this summer. “Removing this stack is a significant milestone for Brookhaven Nation- al Lab’s overarching environmental restoration program that supports the health and wellbeing of our community and environment,” says Peter Genzer, manager, Media & Communications Office, Brookhaven National Laboratory. The stack that the U.S. Army Corps of Engineers is dismantling at the Brookhaven National Laboratory. Photo: JoAnne Castagna, Public Affairs.

At the top of the stack, a MANTIS Demolition System is set up to safely and efficiently dismantle the structure at the Brookhaven National Laboratory. Photo: JoAnne Castagna, Public Affairs.

Brookhaven National Laboratory’s army of research scientists are hard at work performing research on a wide range of disciplines. The Army Corps is making sure that where they do this critical work for the Na- tion is safe. This is an example of what the MANTIS Demolition System looks like at work. This photo was not taken at this project. Photo: USACE.

DR. JOANNE CASTAGNA is a Public Affairs Specialist and Writer for the U.S. Army Corps of Engineers, New York District. She can be reached at joanne.castagna@usace.army.mil.

23

April 2021

csengineermag.com

Made with FlippingBook Annual report