Source: FirstEnergy Corp.
FirstEnergy Nuclear Operating Company (FENOC)(NYSE:FE) representatives last night at a public meeting informed the Nuclear Regulatory Commission that it successfully completed an outage at its Davis-Besse Nuclear Power Station to replace its reactor vessel head and perform other scheduled maintenance.
FENOC officials also stated that a thorough engineering analysis and assessment of its shield building conducted during the outage confirmed the building's structural integrity after tight cracks were discovered when the building was opened for installation of the new reactor head.
"Davis-Besse Nuclear Power Station employees are committed to ensuring safe plant operations that support the health and safety of the public," said Davis-Besse Vice President Barry Allen. "Our investigation and analysis of the shield building demonstrates that the building is a robustly designed and reinforced structure that is able to perform its safety function."
To ensure continued safe operations, Davis-Besse has committed to taking actions over the next several months to provide additional support to its conclusions about the shield building. These include completing a rigorous root cause evaluation, conducting inspections of the shield building near confirmed cracks to verify they have not spread and developing a long-term building monitoring plan.
Industry-recognized structural concrete experts assisted Davis-Besse personnel with the assessment of the shield building. Extensive visual inspections, electronic testing and concrete sampling were performed on the building's walls. Cracks discovered are mainly confined to the building's architectural elements, with two small regions near the main steam lines and portions of the top 20 feet of the building also containing similar tight cracks.
The shield building is a 2 1/2-foot thick reinforced concrete structure that provides biological shielding, protection from natural phenomenon including wind and tornados and additional shielding in the event of an accident. This building surrounds a 1 1/2-inch carbon steel vessel containing the reactor.
Davis-Besse is part of FirstEnergy Nuclear Operating Company, a subsidiary of FirstEnergy Corp.,which also operates the Beaver Valley Power Station in Shippingport, Pennsylvania , and the Perry Nuclear Power Plant in Perry, Ohio .
