Grand Gulf Nuclear Station Apparently Falling Apart: Another Scram Follows “Five Unplanned Downpower Events” In Less Than One Year

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cancer, Claiborne County, clean water, dangers of nuclear, degraded reactor recirculation pump seal, Entergy, environment, Failed open turbine bypass valve, Grand Gulf Nuclear Power Station, hot shutdown, loss of electrical power transformer, Mississippi, Mississippi River, NRC, nuclear, nuclear accident, nuclear disaster, nuclear energy, nuclear industry, nuclear power, nuclear power plant, nuclear reactors, nuclear safety, reactor recirculation system vibrations, risk management, SCRAM, steam leak condenser bay, turbine bypass valve opening, unplanned downpower events, US NRC, USA, water

Construction of Grand Gulf Nuclear Power Station begin over forty-four years ago in May of 1974, and it was commissioned in 1985 or over thirty-three years ago. Would you feel safe driving on the highway in a vehicle of this age? And, this is a nuclear power station. The ionizing radiation speeds up material degradation. Windscale, Chernobyl, and Fukushima have taught that the impacts of nuclear disasters are not limited to the immediate area. The impacts depend upon wind direction, which is variable.

On November 5th: “The NRC’s review of Grand Gulf Nuclear Station identified that the Unplanned Power Changes Per 7,000 Critical Hours performance indicator has crossed the Green-to-White threshold. The performance issues included in this performance indicator were associated with five unplanned downpower events that occurred from the fourth quarter of 2017 through the third quarter of 2018. These events included a degrading reactor recirculation pump seal, a loss of an electrical power transformer and subsequent reactor recirculation system vibrations, a steam leak in the condenser bay, an inadvertent downshift of reactor recirculation pumps from fast to slow speed, and an inadvertent isolation of a feedwater heater.” https://www.nrc.gov/reactors/operating/oversight/letters/gg_2018q3.pdf

The event time, below, is listed as midnight on December 12th, and yet the manual scram was not undertaken until almost 2 pm? Is this a typo or they took this long to react? It wasn’t reported until 5.29 pm, so it’s not the reporting time. “MANUAL REACTOR SCRAM DUE TO FAILED OPEN TURBINE BYPASS VALVE
“At 1351 CST, the reactor was manually shutdown due to ‘A’ Turbine Bypass Valve opening. The Main Steam Line Isolation Valves were manually closed to facilitate reactor pressure control. Reactor level is being maintained through the use of Reactor Core Isolation Cooling System, Control Rod Drive System, and High Pressure Core Spray System. High Pressure Core Spray System was manually started to initially support reactor water level control. Reactor Pressure is being controlled through the use of the Safety Relief Valves and the Reactor Core Isolation Cooling System. The plant is stable in MODE 3. “The cause of the ‘A’ Turbine Bypass Valve opening is under investigation at this time. “The NRC Resident Inspector has been notified.” https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2018/20181213en.html

See important discussion here: http://steamshovel2002.blogspot.com/2018/12/junk-plant-grand-gulf-christmas-season.html

This is the reactor status for the year all on one page so you can do a search for the name of a reactor and see what percent power it’s at: https://www.nrc.gov/reading-rm/doc-collections/event-status/reactor-status/2018/2018PowerStatus.txt

See too: “Downtime at ‘aging’ Grand Gulf attracts increased scrutiny” by Edward Klump and Kristi E. Swartz, E&E; News reporters Energywire: Tuesday, December 4, 2018 http://web.archive.org/web/20181204180437/https://www.eenews.net/stories/1060108635

More about Grand Gulf: https://miningawareness.wordpress.com/2016/12/08/most-powerful-us-nuclear-reactor-not-working-for-months-special-inspection-report-pending-us-nrc-renews-license-for-a-total-of-59-years-anyway/

Nearby, a nuclear power station of a similar model – River Bend – last month:
“At 0046 CST, River Bend Station experienced an automatic reactor scram on high reactor pressure. Initial indications are that the cause of the scram was an uncommanded closure of the #3 turbine control valve.” https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2018/20181112en.html

https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2018/20181213en.html