Comprehensive Decommissioning International (CDI) is backed by decades of experience through its corporate parents, Holtec International and SNC-Lavalin.
Holtec clients span the globe; over 115 nuclear plants rely on Holtec’s dry storage technology for their storage and transportation needs. Holtec’s wet and dry storage and transport systems provide confinement, radiation shielding, structural integrity, criticality control, and heat removal for used nuclear fuel. Holtec remains the world leader in spent nuclear fuel storage technology design and implementation and has supplied over $4 billion of nuclear power plant components since the late 1980s.
SNC-Lavalin (SNCL) brings significant U.S. decommissioning expertise in both commercial and government markets. This expertise includes the baseline planning, license transfer, project delivery through fuel transfer, and reactor segmentation at the Zion station. This team also managed the United Kingdom’s fleet of 22 Magnox reactors through operation and into decommissioning. More recently, SNCL has enjoyed success safely progressing cleanup efforts at Fukushima Dai-ichi in Japan, the Ringhals Units 1&2 in Sweden and the Nuclear Power Demonstration (NPD) reactor in Canada.
Vermont Yankee, USA
To support decommissioning of the Vermont Yankee Nuclear Plant, Entergy Nuclear signed a contract with Holtec to defuel the Vermont Yankee (VY) spent fuel pool. The overall project scope included construction of a second Independent Spent Fuel Storage Installation (ISFSI) pad, security expansion, engineering, licensing, manufacturing, delivery and loading of 45 HI-STORM cask systems, all on a turnkey basis.
In just over 3 ½ years from plant shut down, VY’s spent fuel pool was completely defueled (i.e., no spent fuel assemblies remain in the pool) setting a new industry benchmark. A total of 2,996 spent fuel assemblies were loaded into the dry storage canisters. The final ISFSI pad now contains a total of 58 HI-STORM systems of which 13 were loaded by VY while the plant was still operating and the remaining 45 casks were loaded after the plant shutdown.
Use of Holtec’s patented MPC-68M canister technology, featuring the Metamic-HTTM fuel basket, allowed for NRC approval of loading spent fuel with as little as two years cooling time into dry storage canisters. Safe and early defueling of the spent fuel pool paved the way for decommissioning of the VY plant.
Fukushima Dai-ichi, Japan
At Fukushima, SNCL deployed water treatment technologies, dewatering solutions, and new storage/disposal canisters to support decommissioning. Water being processed consists of sea water used to cool the damaged reactor and ground water that has leaked into the basements of the damaged reactors. The addition of seawater added complexity to the cleanup.
At the time, historic knowledge of radiochemistry had been based on nitrate (fuel reprocessing), not chloride (from sea water). Chloride has a big influence on nuclide speciation. Time sensitive research and testing was conducted in efforts to predict the behavior of nuclides in chloride. Initial emergency responses were highly effective in controlling high radiation dose in water by removing cesium. The liquid waste processing (LWP) systems were modified after numerous laboratory and bench scale testing that focused on creating new media that targeted specific nuclides. The systems have a throughput of greater than 2,100 m3of water per day. These systems are still in operation to date, meeting process requirements including the removal of over 62 nuclides; creating non-detectable levels which are below World Health Organization drinking water standards.
Ringhals Units 1&2, Sweden
Vattenfall and Uniper own the Ringhals sites, located south of Gothenburg in the Varberg Municipality. Vattenfall announced that both Ringhals Units 1; a Boiling Water Reactor (BWR), and 2; a Pressurized Water Reactor (PWR) shall cease operations in 2020 and 2019, following an economic review. Vattenfall commissioned SNCL to undertake an in-depth verification of the current decommissioning baseline and in doing so generate a Cost Estimate Summary Report, supported by a new detailed preliminary schedule that could be evolved into the first fully executable plan for the site. To execute these works, Vattenfall and SNCL entered into a collaborative framework, creating an environment of sharing, challenge and collective knowledge to realize the benefits of site knowledge in combination with global experience. SNCL deployed subject matter experts from both the United Kingdom and United States to deliver this commission.
Zion Nuclear Power Station, USA
Many current Atkins/SNC-Lavalin employees were part of the original team to transition ownership and start the decommissioning of Zion including the General/Project Manager, and executive Management team. Early activities included working with Exelon on the License Transfer Application, a prompt DECON PSDAR, and numerous other licensing activities associated with reconfiguring the security, fire protection, and quality assurance plans. This initial team placed all major procurements for reactor vessel segmentation, rail upgrades, electrical reconfiguration, access to containment, hiring of craft workers, and performed all characterization work.
Big Rock Point Nuclear Power Plant, USA
Consumers Energy awarded one of SNCL’s legacy companies (BNFL Inc.) a contract for major component removal at the Big Rock Point restoration project in Charlevoix, Michigan. BNFL’s scope included the removal of all primary system components including the reactor vessel and decontamination/demolition of the Radioactive Waste Building and the Alternate Shutdown Building.
Magnox Reactor Fleet, UK
ATK Energy EU Ltd (a United Kingdom subsidiary of SNCL), together with its legacy subsidiaries held the contracts and licenses to operate, defuel, and decommission 22 Magnox nuclear power reactors at 10 geographically dispersed sites (904 acres comprising 1,000 buildings and 10M ft2 of floor space, including reactor buildings, turbine halls, spent fuel storage ponds and handling facilities, waste management facilities, and ancillary buildings/infrastructure). This work was performed on behalf of the Nuclear Decommissioning Authority (NDA), a UK Government entity similar to DOE Environmental Management (EM) in mission and purpose.
University of Alberta SLOWPOKE-2 Facility, Canada
Between 2016 and 2018, SNC-Lavalin successfully decommissioned and decontaminated the University of Alberta SLOWPOKE-2 Facility (UASF) located in Edmonton, Alberta. The space occupied by the facility is deemed to be suitable for unrestricted use, and it is expected to be confirmed by the CNSC by revoking the current operating license. The decommissioning activity included concrete blocks removal, the dismantling and removal of the reactor and auxiliary components, removal of contaminated areas from pool floor by intrusive methods and the HEU core and radioactive waste transferred into dedicated containers for shipment to licensed facilities for final storage. The final radiological survey was performed in the reactor pool, the exhaust ventilation system and the facility rooms affected by decommissioning work.
CANDU Reactor Life Extension Projects – Korea, Canada, Argentina
Since 2007, SNC-Lavalin has been successfully refurbishing units in the global CANDU® reactor fleet to extend their useful life. The company has developed and deployed the highly automated remote tooling systems used to remove, volume reduce, and transport the highly radioactive reactor core components. Work also include the design and construction of on-site facilities to safely store the removed reactor core components. When completed, the life of the CANDU reactor is doubled. To date, four units have been refurbished in Ontario, New Brunswick, and Korea. Two projects are currently being executed by SNC Lavalin to refurbish four reactor units in Ontario and one reactor unit in Argentina. SNC-Lavalin was also awarded a further project commitment to refurbish an additional six reactors in Ontario over the next twelve years.
US Government Projects
Through its subsidiaries (including joint venture companies) SNCL has performed over 100 waste cleanup, decommissioning and site remediation projects for the U.S. Department of Energy and the U.S. Department of Defense. SNCL’s portfolio contains site management, engineering and services including:
- Decommissioning and site closure plan development
- Historical Site Assessments and D&D cost estimation
- Providing radiation protection and radioactive waste staff and expertise
- Characterization of environment, facilities, and components
- Remediation operations, including decontamination, demolition, and debris/soil removal, packaging, transportation, and disposal
- Large component removal, engineering, licensing activities, transportation, processing, and disposal
- Operation of onsite waste management and volume reduction activities
- On-site bulk assay for demolition debris and rubble
- Cleanup of sites to end-point criteria; final status surveys to allow for unrestricted release; implementation of MARSSIM guidelines
- Site restoration