DEMOLITION, WRECKING AND RECYCLING TODAY SPECIAL ADVERTISING SECTION Deconstructing a Legacy Power Plant The decommissioning and demo-lition of legacy power plants and related facilities are among the most demanding construction activities. Whether coal or nuclear, both tactically and physically, every project requires detailed plans, a heightened emphasis on worker safety and often a broad skill set outside the demolition norm. Add tight timelines and high-risk tasks, and the pressure only rises. The optimal strategies that deliver quality outcomes are developed through experience, proven expertise in means and methods and, at times, a creative mindset. North American Dismantling Corp. (NADC) has a long history of success-fully deconstructing power plants of all scopes, scale and complexity. The following two projects shine a light on that specialized expertise. multiple implosions. One of the most challenging aspects of this project to date was the removal of the three emissions stacks. To ensure the safe removal of these structures, NADC partnered with an engineering firm, Applied Science International, and a specialty implosion contractor, DemTech. The twin stacks, each measuring approximately 700 ft tall, were located immediately adjacent to the boiler house. The third stack, approxi-mately 540 ft tall, was connected to the plant’s environmental scrubbers. After three months of planning and modeling, charges were strategically placed around the stack bases, safely bringing them down in a controlled implosion. That effort was followed up by the implosion of the plant’s two cement hyperbolic cooling towers (500 and 550 ft tall) along with the turbine bay, making this NADC’s fourth successful implosion in the last two years. Steel and other metals have since been hauled from the site for recycling. Power-generation turbines and other equipment are being removed from the boiler house and other buildings for reclamation, with full demolition of the boiler house on schedule for Fall 2023. The project is on track for completion in early 2024. debris from a former uranium-ore processing facility in Moab, Utah. North Wind Portage (NWP) was contracted by the Department of Energy (DOE) to move the tailings to a location away from the Colorado River. NWP selected NADC to handle the buried debris. In coordination with its abatement partner, NADC developed a plan for abatement and extraction that was reviewed by the DOE, the State of Utah, Radiological Controls and NWP. While preparing for this project, all crews working on site attained Radiological Worker II certifications. The scope of work for this project included the demolition of the Atlas Building, including asbestos abatement, excavation, size reduction of equipment and tools, mill debris and 14 buried autoclaves. Within the Atlas Building, the NADC team safely demolished and removed two concrete vaults and sub-grade foundations. The most unique challenge of this project was the removal of the buried autoclaves, each wrapped in asbestos-containing mate-rial. Due to the large volume of ACM found surrounding and within the autoclaves, the team filled and loaded 8,000-lb “super sacks,” which were then weighed and transported outside the contaminated area and subsequently moved to the offsite disposal cell. Mill debris included troughs, sluices, mixing equipment and grinders that were part of the uranium mill. Many of the large pieces were buried in the tail-ings pile, which required size reduction adequate to fit in 2-ft lifts at the offsite disposal cell. Hot water power washing equipment decontaminated equipment and tools before transport from the site. The size reduction of the boneyard equipment (e.g., dozers, haul trucks, semi-tractors, pickups) required a hot work permit and a designated burn yard to cut the equipment down to required sizes. The State of Utah and DOE were complimentary in their assessment of the performance of the work in the ACM landfill, especially the removal and downsizing of the autoclaves. enr.com/SpecialAd A Super-Size Challenge Team NADC has been actively working on the demolition, dismantle-ment, and abatement of a retired, 236-acre, coal-fired power station in Pennsylvania. It’s a multi-year project that has energized NADC to come up with safer and more efficient methods to inspect, abate, demolish and remove multiple systems. Over the last nine months, the team has removed multiple structures, including electrical trans-formers, three scrubber duct towers and associated buildings and two turbines; completed the demolition of a limestone building, coal hopper building, turbine bay building and multiple warehouses, and coordinated the completion of Strategic Removal Out west, the Moab Uranium Mill Tailings Remedial Action (UMTRA) project includes the relocation of the estimated 16-million-ton pile of uranium mill tailings and previously demolished Controlled implosion of two hyperbolic cooling towers. 34 | October 16/23, 2023 PHOTO: DEMTECH/NORTH AMERICAN DISMANTLING CORP.
ENR Sections Demolition, Wrecking & Recycling Today: Page-34
