10/31/14 DAM ISSUE! Power Reactor Event Number: 50580 Facility: WATTS BAR Region: 2 State: TN Unit: [1] [2] OFFSITE NOTIFICATION AND PRESS RELEASE REGARDING BOONE DAM STABILITY ISSUES On October 30, 2014, at 1100 EDT, TVA conducted a briefing for government officials and other stakeholders regarding the decision to accelerate the Boone Reservoir annual drawdown after discovery of a sink hole near the base of the embankment and a small amount of water and sediment found seeping from the river below the dam. TVA is continuously monitoring the dam and conducting an investigation to determine the source of the water seepage. The dam is located upstream of all three TVA nuclear sites. There are currently no nuclear plant operability or safety issues, and TVA is assessing the impacts on the plant licensing bases. A press release was issued at approximately 1300 EDT. This notification is being made in accordance with 10 CFR 50.72(b)(2)(xi) due to notification of other government agencies and a news release. The NRC Senior Resident Inspector was notified. The licensee is evaluating this event for potential impact on the design basis flooding level. Power Reactor Event Number: 50581 Facility: SEQUOYAH Region: 2 State: TN Unit: [1] [2] OFFSITE NOTIFICATION REGARDING BOONE DAM STABILITY ISSUES On October 30, 2014, at 1100 EDT, TVA conducted a briefing for government officials and other stakeholders regarding the decision to accelerate the Boone Reservoir annual drawdown after discovery of a sink hole near the base of the embankment and a small amount of water and sediment found seeping from the river below the dam. TVA is continuously monitoring the dam and conducting an investigation to determine the source of the water seepage. The dam is located upstream of all three TVA nuclear sites. There are currently no nuclear plant operability or safety issues, and TVA is assessing the impacts on the plant licensing bases The licensee has notified the NRC Resident Inspector. Power Reactor Event Number: 50582 Facility: BROWNS FERRY Region: 2 State: AL Unit: [1] [2] [3] OFFSITE NOTIFICATION AND PRESS RELEASE REGARDING BOONE DAM STABILITY ISSUES On October 30, 2014, at 1100 EDT, TVA conducted a briefing for government officials and other stakeholders regarding the decision to accelerate the Boone Reservoir annual drawdown after discovery of a sink hole near the base of the embankment and a small amount of water and sediment found seeping from the river below the dam. TVA is continuously monitoring the dam and conducting an investigation to determine the source of the water seepage. The dam is located upstream of all three TVA nuclear sites. There are currently no nuclear plant operability or safety issues, and TVA is assessing the impacts on the plant licensing bases. A press release was issued at approximately 1300 EDT. This notification is being made in accordance with 10 CFR 50.72(b)(2)(xi) due to notification other government agencies and a news release. The NRC Senior Resident Inspector was notified. AND Power Reactor Event Number: 50579 Facility: FITZPATRICK Region: 1 State: NY Unit: [1] REACTOR BUILDING VACUUM BELOW TECHNICAL SPECIFICATION LIMIT On the evening of October 28, 2014 at 1708 EDT, with James A. FitzPatrick (JAF) Nuclear Power Plant operating at 100 percent power, the Reactor Building differential pressure decreased below the JAF Technical Specification (TS) Surveillance Requirement (SR) value of at least 0.25 inches water vacuum for a period of thirty-four (34) seconds. This occurred during restoration of the Reactor Building Ventilation System (RBVS) following planned maintenance. The Reactor Building differential pressure was 0.50 inches water vacuum with the A RBVS fans in-service in conjunction with the Standby Gas Treatment System (SGTS). The Reactor Building differential pressure decreased to 0.19 inches water vacuum when the SGTS was secured. The Reactor Building Vent was subsequently isolated, and the alternate B RBVS fans were placed in-service; the differential pressure increased to within the required 0.25 inches water vacuum value. The JAF TS bases associated with Secondary Containment state that, for Secondary Containment to be considered OPERABLE, it must have adequate leak tightness to ensure that the required vacuum can be established and maintained. Troubleshooting activities indicated that the transient was due to a non-safety related, non-TS damper downstream of one of the A RBVS fans that did not fully stroke open. The subject damper is not part of Secondary Containment, and has no safety related function. This condition did not impact the leak tightness of Secondary Containment or the ability of the associated equipment to establish and maintain the required differential pressure. Secondary Containment would have fulfilled its safety function. However, because the JAF TS SR value of 0.25 inches water vacuum was not met, Secondary Containment was considered Technical Specification INOPERABLE for a period of thirty-four (34) seconds. The Secondary Containment is considered a single-train system; therefore, this condition is reportable pursuant to 10 CFR 50.72(b)(3)(v)(C) as an event or condition that could have prevented fulfillment of a safety function. The licensee notified the NRC Resident Inspector. plus other reportable events.... nrc.gov/reading-rm/doc-collections/event-status/event/en.html
Posted on: Fri, 31 Oct 2014 12:41:58 +0000
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