Wm. Dickson Company
Demolition and Safe Storage Enclosure Construction for 105-N and 109-N Buildings
What makes it interesting?
This project involved deactivating, disassembling, demolishing, and decommissioning the last remaining nuclear reactor and heat exchanger building 109-N, which produced plutonium and was closed in 1991. The Safe Storage Enclosure Roofing System is designed to withstand extreme temperatures, wind, rain, snow, volcanic ashfall and seismic loads, people and animal intrusions, etc., to safely store the reactor until an anticipated one-pierce removal is initiated at the end of a storage period of up to 75 years.
How HCSS Software assisted with this project
HeavyBid was instrumental in the bidding success of the Demolition andSafe Storage Enclosure Construction for 105-N and 109-N in a number of ways. The RFP was set up in both unit bid prices and lump sum. Various categories and sub-categories allowed HeavyBid to focus on specific groups of unit bid items and lump sum items and to break them out into sub-categories to isolate specific work evolutions in each bid item. It also allowed Wm. Dickson Company to bid certain items with and without taxes and to implement escalation in each additional year after the base year. The detailed reports HeavyBid generates enabled Wm. Dickson to compare actual phase and cost code accounting reports to the bid estimate. These reports proved invaluable over the course of the 40-month contract.
Project Description:The Demolition and Safe Storage Enclosure Construction for 105-N and 109-N Buildings involved deactivating, disassembly, demolition and decommissioning the last remaining nuclear reactor 105-N (4,000 Megawatt thermal nuclear reactor that produced plutonium) and heat exchanger building 109-N that were permanently shut down in 1991.
The demolition of buildings 105-N and 109-N included most portions of the concrete structures to the outside of the shield walls around the reactor area, steam generator cells, and pipe gallery. All demolition concrete and CDL debris, chemically and/or radiologically contaminated soil and concrete, miscellaneous debris/structures, and underground piping and conduit were size reduced, sorted, loaded and transported to the Environmental Restoration Disposal Facility (ERDF) on the Hanford Reservation for proper disposal. Magnatite reinforced concrete 5 to 6 feet thick proved challenging during the demolition processes, however, a fleet of excavators and large demolition hammers allowed Wm. Dickson Company to stay on schedule and within budget of the HeavyBid estimate.
In addition, once demolition activities were completed, another element of this Design-Build project was to design a Safe Storage Enclosure Roofing System above the abandoned reactor and heat exchanger buildings.
Working in a remote desert location one hour from the nearest city presented challenges for employees, subcontractors and suppliers. The summertime brought out rattlesnakes, bats, mud daubers, and black widow spiders, and winter brought the bitter chill of working in an environment where the high temperature was well below freezing.
This $38 million project occurred over the course of 40 months.