River Bend Just scrammed. The term in my heading "Their Southern Regional Problem" means, I understood Grand Gulf's historic erratic operation is not just a plant centric problem, but a Entergy regional weakness.
Reposted from 1/17/18
Unbelievable. So this startup the peak power level got to 91%.
Facility: GRAND GULF
Region: 4 State: MS
Unit: [1] [ ] [ ]
RX Type: [1] GE-6
NRC Notified By: RALPH FLICKINGER
HQ OPS Officer: DONG HWA PARKNotification Date: 01/30/2018
Notification Time: 21:56 [ET]
Event Date: 01/30/2018
Event Time: 18:22 [CST]
Last Update Date: 01/30/2018Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATIONPerson (Organization):
RICK DEESE (R4DO)
Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode 1 M/R Y 91 Power Operation 0 Hot Shutdown
Event Text
MANUAL REACTOR SCRAM DUE TO MAIN TURBINE LOAD OSCILLATIONS
"On 1/30/2018 at 1750 [CST], the Reactor Pressure Control Malfunctions ONEP [Off Normal Event Procedure] was entered due to main turbine load oscillations of approximately 30 MWe peak to peak. At 1822 [CST], a manual reactor scram was inserted by placing the Reactor Mode Switch in Shutdown due to continued main turbine load oscillations.
"Reactor SCRAM ONEP, Turbine Trip ONEP, and EP-2 were entered. Reactor water level was stabilized at 36 inches narrow range on startup level and reactor pressure stabilized at 933 psig using main turbine bypass valves.
"Reactor Water Level 3 (11.4 inches) was reached which is the setpoint for Group 2 (RHR to Radwaste Isolation) and Group 3 (Shutdown Cooling Isolation). No valve isolated in these systems due to all isolation valves in these groups being in their normally closed position. The lowest Reactor Water level reached was -36 inches wide range.
"No other safety system actuations occurred and all systems performed as designed.
"That event is being reported under 10CFR 50.72(b)(2)(iv)(B) as any event or condition that results in actuation of the Reactor Protection System (RPS), when the reactor is critical and also reported under 10CFR 50.72(b)(3)(iv)(A), as any event or condition that results in actuation of RPS."
The MSIVs are open with decay heat being removed via steam to the main condenser using the bypass valves. Off site power is stable, and the plant is in a normal shutdown electrical lineup. RCIC (Reactor Core Isolation Cooling) was out of service for maintenance, and the reactor water level did not reach the system activation level. The cause of the main turbine load oscillations being investigated.
The licensee notified the NRC Resident Inspector.
Update Jan 30
80%
I mean, what is going on in this plant that is causing them to bounce around power so much.I just got done talking with to the senior resident. He emediately recognized my voice. Amazingly it is his last day at the site. He leaving permanently at noon. He got promoted. I have been talking to him on and off for years. He is going to be boss of inspectors at Beaver Valley, TMI and Oyster Creek. He is a good guy.So basically Grand Gulf is a very troubled plant. Upon the extended shutdown, the resident says Entergy seen the light. They wiped out management and brought in new people. The plant has gotten extremely safety consciences. Every little burp they are investigating intensely and down powers on a whim. They are a regulated plant, so the ratepayers pick up the tab. So that is the nature of the startup problems. He said recently the plant has a secondary pipe steam leak. This caused one down power. That cut out the pipe and put in new a new piped. They also cut out four other similar pipes and welded in new pipe. The senior said per regulations they could have just ignored the leak. That is the way they did business in the past.He also implied the secondary system are a mess. They just didn't spend big money keeping them in good shape beginning in the 1990s. He thought Grand Gulf was going on a massive secondary system refurbishment next outage. I still think the massively expensive uprate somewhere beginning in around 2012 is at the root of their penny pinching leading to their secondary system problems today.
Update Jan 29
Ok, the scram should be coming around any day now. Is it just one
***(Jan 31) So, about 24 hours they have the scram I predicted the scram and look how close the scram was to my prediction. You got to create a pretty complete model in your head to be able to do what I can do.big problem dogging these guys this startup, or a set of problems showing up causing this kind of power history.
Jan 27 61%
Jan 28 81%
Jan 29 87%
Update June 26
80%
Jun 25
78%
Jan 24
Back to 63% power today.
Update Jan 23
They will run out of fuel before they can get it up to 100%. At 70% today.
Update Jan 22
Highly erratic and extremely slow startup post shutdown.
Fri 40% power
Sat 61%
Sun 66%
Mon 54%
River Bend is still shutdown and ANO up to 100%. Good boy ANO.
Update Jan 19
Traveling at the speed of light. Up to 40% today. That is a whopping 13% power in 24 hours. It will be refueling time by the time they get to 100% power. Talking about wasteful operations. Say a normal nuclear plant has a capacity of 95% power and a bad plant has 50% capacity factor. So what happens to the bad plant's U235 with 45% capacity factor? It is not like a car who has been idle for a month. What happens to the gas you didn't use in the idle month? It is just money you didn't spend, you could divert it to other uses. But it doesn't work that way for the nukes. That 45% average capacity factor, an enormous amount of U235 and electricity they didn't use with poorly operating nuclear plants...that good U235 they just throw in the nuclear plant. A plant plans for how much U235 and particular pin concentration they will use for a particular estimated capacity over the operating period. It is a extremely complicated process refueling the total cycle's U235 fuel load and their particular pin concentration. We just don't have the ability yet to use all the estimated cycle fuel load that ends up not used because of a poor capacity. That 45% average capacity factor (the equivalent U2350) not used in the bad plant, it gets thrown in the toilet. The safety rules says, that gas you didn't use in the idle car for a month, it can't be deferred for later use. Nobody can use it. The U235 has to be thrown away.
Just saying, that U235 Grand Gulf didn't use in their historically atrocious capacity factor over many years, it is just a waste and thrown away. They are effectively using some twice the U235 fuel than a good plant.
Update Jan 18
Grand Gulf is up to a whopping 27% power in 24 hours. Remember recently, the troubled Pilgrim plant shutdown? In 24 hours of startup they were at 50% power . In another 24 hours, damn close to 100%.
Hmm, ANO 2 is at 95% power.
***So Grand Gulf just started up. They been having a lot of staying at power problems lately.
ANO 2 is still at 81%.
River Bend is still shutdown.
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