Source: EM Update | Vol. 12, Issue 36; Contributor: Ben Williams | November 24, 2020

p

A close-up view of the drone, which resembles a mini-helicopter. Following commands from a ground-based operator, the camera-mounted drone circles around the stack making recordings that can be evaluated by engineers and safety experts.

What’s the safest way to climb and inspect a 70-year-old, 250-foot-tall brick exhaust stack? That’s the question employees in Oak Ridge worked to answer, and through the use of technology and innovation, they determined no one had to climb after all.

In October, the Oak Ridge Office of Environmental Management (OREM) used a drone to conduct visual inspections inside and outside the 3039 stack. The chimney-like structure, built in 1950, is located in the central campus area of the Oak Ridge National Laboratory. Due to the age of the structure, it requires periodic inspections to evaluate its structural integrity.

The 3039 stack provides high-efficiency particulate air (HEPA)-filtered ventilation exhaust for numerous radiological facilities, including various isotope facilities in the central campus. OREM is responsible for its operation and maintenance because it is part of the Liquid and Gaseous Waste Operations infrastructure.

p

A view of the 3039 exhaust stack, which was built in 1950 and stands 250 feet tall. It provides high-efficiency particulate air (HEPA)-filtered ventilation exhaust for numerous radiological facilities, including various isotope facilities in Oak Ridge National Laboratory’s central campus.

The drone resembles a mini-helicopter. Following commands from a ground-based operator, the camera-mounted drone circles around the stack, searching for flaws that could threaten the stack’s structural integrity. The cameras record as the drone circles the stack and as it is lowered into the stack. Then, engineers and safety experts assess the footage to note any areas of concern.

The external portion of the inspection was performed using an onboard camera system, while the internal portion was performed by hovering the drone over the top opening and lowering the camera into the stack.

Previous stack inspections required inspectors to physically climb the 250-foot-tall structure. Now, technology is eliminating the need for workers to climb the stack and establish work platforms high in the air. This is the latest example of how OREM and its contractors are working together to identify approaches that will keep employees safe while performing EM’s complex and challenging cleanup mission.