Thursday, April 23, 2015

New CDBI Inspection at Waterford, NRC says they could have melted down in Hurricane?


Updated on Apr 23: 0500382

 See how in Brunswick the NRC inspectors discovered DG day tank vent pipe vulnerabilities... 

 On Waterford's corroded DG day tank vent pipe, why wasn't it protected from tornadoes?  

Originally posted on 1/7/2015
This really ask us how close we are to a international incident. We are walking on a lot thinner ice as a nation than we realize.
By the way, even having safety related DG fuel oil tubing the operators have never been up to the roof?

 More embarrassing than anything, Entergy's staff didn't catch this on their own. You notice the shadowy way the NRC hints the New Orleans severe weather and excessive rainfall could be outside the norms of anywhere else in the country. Stick that is risk perspective pipe and smoke it.



Hurricanes of Category 3 or greater passing within 100 miles of New Orleans 1852–2005. from NOAA

Waterford had in excess of 10 inches of rainfall in Katrina...had similar amounts in more recent hurricanes. Basically the NRC says, Waterford had corroded and leaking  fuel oil day tank(s) roof vent tubing. In a large rainfall, water on the roof would have ponded...would have covered the corrode tubes that had holes in it. You notice they don't show us pictures

The ponding water would have leaked into the diesels fuel oil tank and that would have permanently shutdown both diesel generator. The below is how the NRC frames it ( they don't say how many rainfall event). 
'Engineering review of the available meteorological tower data shows peak rain rates of 3.8 inches per hour have been experienced at the site in in the last two years." 
Per the NRC:
"It is unknown how long this corrosion has existed."  
So the huricane winds vibrates the thin wall corroded DG tubing, maybe the wind picks up debis and hit the tubing...this creates the break.

I believe all communication to the outside was lost in Katrina at Waterford. The grid was down for weeks and the plant was on the diesel generators for weeks. Here below the NRC says they would have stopped working:
"If required to operate after a Design Basis rainfall event over the past 3 years both the train A and B EDGs could have been inoperable due to water intrusion into the EDG Feed Tanks through the corroded holes." 
Here is the scenario. I wonder what size hurricane would now take take out the the transmission system surrounding Waterford. Did they upgrade the transmission?
1) The front side of the hurricane quickly takes out the transmission system.
2) The plant would immediately get re-energized by both diesel generators starting up and connecting to the buses. 
3) The eye wall would go over the plant...copious amounts of water would overwhelm the roof drains on the Reactor Auxiliary Building  roof in this first swipe. It would ensue huge ponding of water.
4) All during the front end of the hurricane, rain water would be draining into the the diesel generator local fuel oil tanks through the corroded vent line tube(s)
5) Shortly after eye wall would passes, both diesels generator would start sputtering. They would both trip and can't be started. Nobody would know why the DGs stopped. It would haunt the operators with not knowing why the DGs tripped.
6) It would be the first time a nuclear plant in the USA had to cycled into a station blackout procedure (SBO). If the accident gets under control at this point, can you imagine the hullabaloo with  the outsiders, that the roof corroded  DG fuel oil tubing got a plant into this position.
7) It would be the first time in the history of the world where the nuclear power plant staff tried to perform a SBO procedure in 110 MPH winds and copious rain.
8) Now how long does those emergency safety system batteries work?  I have no faith the portable dg would get
Can you even imagine how the cable networks and the newspapers would interpret this event? I believe maybe it would come to a fuel melt...probably not as bad a Fukushima. I don't  think you can get into a more complex event as this.

Here below is the LER on it. It doesn't seem the CDBI inspection report has come out yet.

By the way, they had three or four other dg fuel tubing leak through the years and poor maintenance leading to other leaks. You would think a nuclear plant would have high quality thick tubing who doesn't corrode in the weather? Where is the protective covering?
Emergency Diesel Generators Rendered Inoperable By Potential Water Intrusion Into Diesel Fuel Oil Feed Tanks 
LER-2014-04-00
During a walkdown of the Emergency Diesel Generator Feed Tank A and B vent lines on October 22, 2014, an NRC Component Design Basis Inspection inspector identified corrosion on the Emergency Diesel Generator Feed Tank A and B vent lines where the vent lines pass through the roof. A visual inspection was performed and revealed that the corrosion had created through wall holes that could allow water into both the train A and B Emergency Diesel Generator Feed Tanks. Follow up analysis has determined that some rainfall amount less than the postulated Probable Maximum Precipitation event could have resulted in water intrusion into the Emergency Diesel Generator A and B Feed Tanks that exceeds the 0.1 percent water content allowed by the vendor technical manual. This could have potentially affected the operability of both the A and B Train Emergency Diesel Generator Feed Tanks and subsequently both trains of the Emergency Diesel Generators. It is unknown how long this corrosion has existed. Compensatory measures were put in place to prevent water ingress should a large rainfall event occur. Follow up analysis has determined that some amount of rainfall less than the postulated Probable Maximum Precipitation (PMP) event could have resulted in sufficient water ponding on the Reactor Auxiliary Building (RAB) [NF] roof to allow water intrusion into the EDG A and B Feed Tanks that could exceed the 0.1 percent water content allowed by the vendor technical manual. This could have affected the operability of both the A and B Train Emergency Diesel Generator Feed Tanks and Emergency Diesel Generators. Engineering review of the available meteorological tower data shows peak rain rates of 3.8 inches per hour have been experienced at the site in in the last two years. Based on the follow-up evaluation, these rainfall rates could have potentially resulted ponding on the RAB roof that would allow in water ingress into the EDG Feed tanks. These rain events have been followed by successful EDG monthly tests. If required to operate after a Design Basis rainfall event over the past 3 years both the train A and B EDGs could have been inoperable due to water intrusion into the EDG Feed Tanks through the corroded holes.

 This it the first swipe with Waterford's reporting to the NRC. Can't you hear Entergy's bitching over wildy excessive regulatory burderns including the CDBI. 

SUBJECT: UPDATE - NOTICE OF UNUSUAL EVENT, PLANT SHUTDOWN, AND LOSS OF OFFSITE POWER AT WATERFORD-3 DESCRIPTION: 
This Preliminary Notification is being issued to update recipients of the Notice of Unusual Event(NOUE), plant shutdown, and loss of offsite power at the Waterford-3 facility in response to Hurricane Katrina. As of August 30, 2005, at 9:00 a.m. (CDT), Waterford-3 remains in the NOUE, because of the loss ofoffsite power. The plant is no longer under a hurricane warning which was the original basis for the emergency declaration. Preliminary assessment of the Waterford-3 plant identified no significant damage to safety systems and structures. The plant is currently in Mode 4 or “hot shutdown,” with both trains of shutdown cooling operable. Onsite safety-related electrical power continues to be provided by the emergency diesel generators. The licensee is continuing efforts to evaluate the condition of the electrical distribution network in the vicinity of the plant which is energized and supplying balance of plant loads. The licensee is planning inspections of electrical transmission facilities in the next 24 hours. Two regional inspectors remain onsite and are monitoring licensee recovery activities.
All NRC CDBI inspections at Waterford. The problem I got, was why wasn't the DG fuel oil day tank roof vent line problem picked up in the first inspection in 2007. The risk based priority system on picking what component system to inspect makes no sense...it's gone haywire.



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