NUCLEAR SHIELDING

Parsons history of providing nuclear engineering services to the U.S. government includes extensive experience in shielding design. Reducing radiation exposure is a major objective of shielding design. For us, these designs include review of facility criteria, source determination, equipment layout considerations, maintenance assessment, and dose rate evaluation. Plant design economic tradeoffs factor in shielding materials, distance, working time, geometry, and facility layout.

Projects may require either neutron or gamma shielding, or both. We have applied a wide variety of shielding materials-steel, ordinary and heavy aggregate concrete, lead, polyethylene, borated materials, masonite, wood, graphite, water, earth, and special composite materials.

Analytical assessment includes source determination, multigroup source compilation, shielding curve generation, activation determination, dose rate evaluations, and scattering/streaming calculations. Our radiation shielding transport calculations use discrete ordinates and Monte Carlo techniques.

One of our most challenging shielding programs was the design and construction of a shelter over the Chernobyl reactor. We provided expert engineering, project management, and technical consultation during the development of plans and studies to convert the damaged reactor into a safe and environmentally sound site. Our approach reduced the planned exposure by a factor of 10 and costs by a factor of three.

Our specialized experience encompasses:

• Radioactive material, processing, handling, and facility design
• Waste treatment, storage, and disposal facility design
• Facility managed modifications and as-built reviews
• Commercial facility design
• Facility walkdowns and baseline documentation services