The agreement, which is an expansion of CB&I’s existing scope of work for 17 other Exelon nuclear power units, is valued at $800m over five years.

Under the contract, CB&I will provide long-term maintenance, modification and construction services for the nuclear power units.

The company will also provide temporary staffing, painting and insulation services at all of the nuclear power units, which are owned and operated by Exelon, bringing the total number of units under contract to 22.

CB&I engineering, construction and maintenance operating group president Patrick Mullen said, "This award underscores CB&I’s expertise in nuclear maintenance, modification and construction and our commitment to ensuring the safe and reliable operation of our customer’s facilities."