06:00 Nov 28, 2018
Discovery of a Condition That Could Have Prevented Fulfillment of a Safety Function
On November 28, 2018, while performing an engineering review of the bases for environmental qualification (EQ) requirements for the Atmospheric Steam Dumps (ASDs), it was determined that applicable EQ requirements had not been applied to a key component of each of the ASDs. The result of this issue is that it the availability of the ASDs for a controlled plant cooldown following a postulated steam line break outside containment cannot be assured.
Callaway is developing a compensatory action temporary plant modification to install insulation that will protect the affected ASD components from the post Main Steam Line Break temperature.
This condition is reportable 10 CFR 50.72(b)(3)(v) for any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to (B) remove residual heat, or (D) mitigate the consequences of an accident.
The issue places the plant in a 24-hour Technical Specification (TS) Limiting Condition for Operations (LCO), 3.7.4.The licensee has notified the NRC Resident Inspector.
Missouri (NRC Region 4)
|10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat|
10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
|Time - Person (Reporting Time:+11.42 h0.476 days <br />0.068 weeks <br />0.0156 months <br />)|
17:25 Nov 28, 2018
|NRC Officer:||Karl Diederich|
|Last Updated:||Nov 28, 2018|
|53759 - NRC Website|