The Tennessee Valley Authority’s (TVA) Enterprise Risk Management (ERM) business unit (BU) focuses on identifying and prioritizing enterprise risks. Annually, ERM leads the preparation of an enterprise risk portfolio, which includes risks across TVA, to aid leadership in strategic and business planning processes. Each BU includes their specific risks in the portfolio and documents the probability of occurrence, financial impact, and actions to manage the risk. TVA Nuclear included Asset/Equipment Failure – Low-Pressure Turbines risk in fiscal year (FY) 2025 ERM risk portfolio. The risk description stated that one or more low-pressure turbines fail to perform as designed and the details only included Units 2 and 3 at Browns Ferry Nuclear Plant (Browns Ferry). The actions to address the risk included installing new turbines and steam-path upgrades. Due to the importance of the reliability of TVA’s nuclear assets, we performed an evaluation of the risk mitigation of low-pressure turbines to determine if TVA was taking planned actions and measuring the impact of completed actions.
We determined TVA has taken actions or has plans in place to address the low-pressure turbine risk. TVA Nuclear has completed 11 of 15 mitigating actions identified for the risk. The 4 remaining actions are expected to be completed between 2028 and 2030. However, we determined TVA was not effectively measuring the impact of completed actions and a change in the risk scope on the probability of occurrence and financial impact. In addition, we identified some risk information was not documented accurately.
