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Nuclear Facility Engineering Services

From concept design, through operations to end-of-life decommissioning we can help you meet and overcome the unique challenges of the nuclear energy life cycle. 

Lead Contacts

Nuclear reactor on the Hudson River in New York. MIHAI ANDRITOIU/
Stock model of nuclear fuel assembly simulation model (not created by Thornton Tomasetti). Peter Sobolev/

We know nuclear power engineering. We provide specialized technical consulting services to manage the risks associated with the entire nuclear fuel life cycle. And it’s not just power plants: our experience runs the gamut of nuclear applications, from research and medical to military. We've supported the national and international civil and government sectors since the mid-1950s, so we know the nuclear industry’s regulatory, safety, quality and security drivers inside and out.

Our team applies innovative techniques in modeling and simulation, testing and R&D to our risk management, design and engineering work, enabling us to deliver solutions that are safer and more cost-effective and reduce risks to personnel, assets and the environment.

We develop and apply the latest state-of-the-art science and engineering to both commercial nuclear power plant and Department of Energy nuclear laboratory projects. We have deep knowledge of government regulations and international best practices. We leverage government-sponsored testing and a wide range of experience from other areas of our business to ensure that you get best-in-class engineering solutions.

Our extensively audited and DOE-approved NQA-1 quality assurance program prepares your nuclear structures for a rigorous and challenging stakeholder review process. As your partner, we’re with you every step of the way – committed to getting your project through this final stage and achieving success with a functioning, fully commissioned building.

We’re focused on the future of energy development. When we deliver answers to your technical problems, we’re also helping to power the future and build a better tomorrow. Here's how:

  • New nuclear development
  • Plant operations support
  • Plant life improvements and extension
  • Waste management, transport and storage
  • Decommissioning and demolition
  • Site security, resilience and assurance

News & Resources

Assystem Wins Two Contracts For New STEP Fusion Plant
November 04, 2021
Assystem and their partners, Thornton Tomasetti, will work with STEP’s research team to develop software capable of undertaking simulations to help define breeder blanket designs that can produce enough tritium to advance the project to the next phase of simulation and testing, moving us closer to achieving commercially viable fusion energy.