Diesel Generator reports (Y2K safety issues)

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Here is an example of questionable diesel generator failure and an example of generator success. (from today NRC event reports)

|Power Reactor |Event Number: 35866 | +--------------------------------------------------------------------------- ---+ +--------------------------------------------------------------------------- ---+ | FACILITY: COOK REGION: 3 |NOTIFICATION DATE: 06/25/1999| | UNIT: [1] [] [] STATE: MI |NOTIFICATION TIME: 23:08[EDT]| | RXTYPE: [1] W-4-LP,[2] W-4-LP |EVENT DATE: 06/25/1999| +------------------------------------------------+EVENT TIME: 20:30[EDT]| | NRC NOTIFIED BY: DAN ETHERIDGE |LAST UPDATE DATE: 06/25/1999| | HQ OPS OFFICER: BOB STRANSKY +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |MIKE JORDAN R3 | |10 CFR SECTION: | | |ADAS 50.72(b)(2)(i) DEG/UNANALYZED COND | | |AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-------------- ---+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-------------- ---+ |1 N N 0 Cold Shutdown |0 Cold Shutdown | | | | | | | +--------------------------------------------------------------------------- ---+ EVENT TEXT +--------------------------------------------------------------------------- ---+ | EMERGENCY DIESEL GENERATOR DECLARED INOPERABLE | | | | "The Diesel Generator Fuel Oil System is designed to provide the required | | amount of diesel fuel to operate the EDGs on each unit for a minimum of | | seven days at the full load capacity of the generators. Two fuel oil | | transfer pumps are provided for each EDG to transfer diesel fuel from the | | storage tank to the fuel oil day tank. From each day tank, the fuel oil | | flows by gravity into the suction of the engine-driven fuel pump. The pump | | provides nine gpm at 35 psig and discharges through a duplex fuel oil filter | | into the two fuel oil supply manifolds. | | | | "Some of the fuel oil which flows from the supply manifold into the | | injection pump is not delivered to the spray nozzle. This excess fuel oil | | circulates through the injection pump, cooling the injection pump, and | | providing lubrication for the fuel oil side of the pump. The fuel oil then | | flows to the return manifold. To maintain a fixed pressure in the supply | | manifold, a relief valve at the end of each supply manifold (SV-200 set at | | 25 psig) bypasses fuel oil to the return manifold. | | | | "On 6/25/99, during routine inspection of the fuel oil lines, it was | | discovered that SV-200 on one of the Unit 1 EDGs was installed backwards, | | effectively blocking the safety valve from relieving excess pressure on the | | supply manifold. This configuration may have existed since initial | | construction. The EDG has been operated successfully many times with this | | condition, but uncertainty about the ability to operate for 7 days, | | especially at low loads, has caused the EDG to be declared inoperable and | | prompted this 4 hour NRC notification. The EDG remains available and will be | | repaired at the earliest opportunity." | | | | The licensee will inform the NRC resident inspector of this notification.

|Power Reactor |Event Number: 35869 | +--------------------------------------------------------------------------- ---+ +--------------------------------------------------------------------------- ---+ | FACILITY: THREE MILE ISLAND REGION: 1 |NOTIFICATION DATE: 06/26/1999| | UNIT: [1] [] [] STATE: PA |NOTIFICATION TIME: 13:18[EDT]| | RXTYPE: [1] B&W-L-LP,[2] B&W-L-LP |EVENT DATE: 06/26/1999| +------------------------------------------------+EVENT TIME: 10:08[EDT]| | NRC NOTIFIED BY: BLAIR |LAST UPDATE DATE: 06/26/1999| | HQ OPS OFFICER: BOB STRANSKY +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |KURT COWGILL R1 | |10 CFR SECTION: | | |AESF 50.72(b)(2)(ii) ESF ACTUATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-------------- ---+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-------------- ---+ |1 N Y 100 Power Operation |100 Power Operation | | | | | | | +--------------------------------------------------------------------------- ---+ EVENT TEXT +--------------------------------------------------------------------------- ---+ | EDG STARTED AND LOADED DUE TO LOSS OF AUXILIARY TRANSFORMER | | | | At 1008, the '1B' 230 kV auxiliary transformer failed for unknown reasons. | | The '1A' emergency diesel generator (EDG) automatically started and loaded | | to its associated 4kV emergency bus. The unit is currently stable at 100% | | power. The licensee stated that EDG will remain loaded to its emergency bus | | until the auxiliary transformer can be restored to service. The NRC | | resident inspector has been informed of this event by the licensee.

-- Anonymous, June 28, 1999

Answers

Scott,

What is so amazing about this information is that it is obvious that these EDG's have not been inspected, tested, and stamped as ready. And this is not even into the Y2k environment. This is not an IT problem, but rather a routine maintenance problem. What it says to me is that there is *lot* of sloppy attention to details going on, and apparently has been going on, for quite some time. May God have mercy on us.

-- Anonymous, June 28, 1999


Not so obvious to me, Gordon. Please explain your conclusion that the EDG hasn't been inspected or tested. Since initial construction of D.C. Cook (circa 1974), I figure this diesel has been tested - minimum - 300 times. I base this on a once per month test frequency over a span of twenty-five years.

Although you obviously know this Gordon, from your extensive airline experience, I'll inform the casual reader that 'inoperable' most certainly does not mean 'will not work'. In fact, you may notice that the statement specifically says that the EDG remains available. It has worked as planned (not exactly as designed, though) for twenty- five years. It will still supply emergency power.

-- Anonymous, June 28, 1999


Nucpwr,

From my extensive airline experience I can tell you that when repairs have been done in a sloppy manner, or inspections have been rushed through and glossed over, the recipe for tragedy is complete. How could an important pressure relief component be installed backwards and remain undetected for so long? Doesn't sound like either professional maintenance or serious inspection to me. The fact that any components that are ready to cause serious trouble have not as yet caused such trouble is not an excuse, safety wise. Again, I offer that from my extensive airline experience. There seems to be a common sense issue at the core of this EDG debate that you are somehow missing. And what I said above regarding inspection, testing, and approval is all inclusive, *not* inspection OR testing. All inclusive. A total package of routine maintenance that got screwed up here. The examples given are what is called "prima facie" evidence in any court of law.

-- Anonymous, June 28, 1999


Actually, I think it would be more correct to say that the recipe has an ingredient. The tragedy never was completed. I also disagree with your inference that this component was ready to cause serious trouble... it was like this for 25 years. I must be missing the common sense issue at the core of this debate. What exactly do you want me to get out of this? Poor construction? Sure. It was put in backwards. That's poor.

Unsafe? No...but it could have been. And, believe me, 'could have been' is the same as 'is' in this business. D.C. Cook will review god knows how many years worth of paperwork, and submit a thousand man-hour report to the NRC. Don't be surprised to see the NRC cautioning every other plant to look closely at thier own EDG's.

But is this an example of screwed up routine maintenance? Not unless that particular relief valve was part of a testing program. If it seemed to be working fine, why would anyone suspect that it wasn't? Bottom line, Gordon, the EDG worked just fine. It would have supplied emergency power. Isn't that what you want?

-- Anonymous, June 28, 1999


Nucpwr,

No that is not what I want. And I'll wager that it is not what anyone in the public wants that is trusting the power company. Just like I don't think you would be too happy if I told you that some bolts that hold the engine on the wing were just discovered to be installed incorrectly, but hey, it's been flying around that way for a while now, so hop onboard, it'll probably be OK for this flight too. Would you hop on board? Would you want to know how something that was a potentially dangerous matter could have been let go like that? These EDG's are the last link in the power safety chain, and if there are two of them there, they should both work flawlessly, not one work and one not, or one have some inherent flaw that hasn't failed so far. And look, you say they are routinely tested. Really? You mean they crank them up and run them at full power output for one week solid without stopping. Because if they are not tested that way, they are not really tested. It's no good if these things are only proven to run for an hour or two every month or so. No good at all. I am truly shocked at your defense of this matter. If that company had caused someone injury over this matter, and ended up in court, do you really think the judge would listen to a defense argument stating that the company had taken all responsible precautions to ensure the EDG was in perfect operating condition? The judge would bust some chops, believe it!

-- Anonymous, June 28, 1999



The length of time this diesel generator could have provided power is questionable. The NRC has not made EDG readiness a top priority and it really needs to. EDGs only have to be tested under load for 24 hours once per year (they are tested for lesser periods once a month). When was the last time the NRC required a 96 hour test? What Ralph Beedle of NEI told me two weeks ago was eye-opening. He was not concerned about oil leaks from EDGs even when I said an NRC inspector told TMI that their's were fire hazzards. Beedle said, So what? As long as they're up to regulations. TMI has since corrected the problem.

The NRC ought to require each plant to test diesel generators for 96 hours under a dummy load before the millennium. You can learn a lot from a dummy.

-- Anonymous, June 28, 1999


I can't argue with the idea of longer duration testing. Scott's required testing timetable is correct. As a weak defense, I will say that a diesel engine is not a complicated thing; and if it starts and runs for a few hours every month, the odds are overwhelming that it will run indefinately. What I do take exception to, is the insinuation that the utility is not taking reasonable precaution to show that the EDG's are going to perform the function that they are designed to perform. When the EDG valve was discovered to be incorrect, the utility called it inoperable and stopped taking credit for one train of emergency power. A pretty reasonable precaution. This will shut them down (without remediation) in seven days. They didn't say 'Hop on board, it'll be OK'. That is an attitude that only the airline industry, with two thousand+ fatalities since 1982, could flaunt. (source: www.ntsb.gov)

-- Anonymous, June 29, 1999

Nucpwr,

That was a nasty stab you just made at the airline industry. Sounds like the pot calling the kettle black, to me. I am going to end this discussion with you on this topic. I don't see that there is anywhere to go with you on it. Time will tell, shortly, if your hearty confidence in your industry is truly warranted.

-- Anonymous, June 29, 1999


Gordon,

You're absoloutely right! We can't have folks taking nasty stabs at the airline industry. This forum is limited to electric utilities.

Come on, just kick in a little right rudder and roll with it like everyone else here does.

-- Anonymous, June 29, 1999


CL,

All right Cl, I'll comment to you. I don't ever defend the sloppy mistakes made in the airline industry that end up killing people. Nor poor training and operator error. Whether we talk about the tragic Air Florida crash in the Everglades a couple years back, or the recent stupid mistakes made by American at Little Rock, I consider these things unforgivable. The difference seems to be that I constantly see defenses of the utilities for equally bad bungling of their basic business conduct. Where is the truth and honesty in the reporting from your side of this?

-- Anonymous, June 29, 1999



Gordon, thanks for standing up for the truth. We live in the same country that put Nutrasweet through years of testing for safety. Numerous products meant for use by individuals or small groups have been pulled from the shelves because of much smaller risks to human health. Automobile recalls have become common-place in this country. I don't know all of the reasons which are going to be behind the NRC's refusal to shut down untested power plants, but I know that it is wrong not to. Electricity is a consumer product. Americans can get along with an electricity shortage, as they have done with other shortages of products. How arrogant to change the standard for the sake of the status quo. I am not eagerly awaiting the "glowing" reports of compliance from the NRC. A. Mc.

-- Anonymous, June 30, 1999

A.Mc,

Thank you, that is exactly what I was trying to get across. You said it even better. Wonder where Ralph Nader is right now and if he's still looking for things that are "unsafe at any speed?". Oh, and Rick, that was not meant to be a jibe at the nukes, per se, just those that are not moving heaven and earth to have a "class act" ready for us.

-- Anonymous, June 30, 1999


Pardon me for jumping in here, but I really need to.

nucpwr wrote:

"Not so obvious to me, Gordon. Please explain your conclusion that the EDG hasn't been inspected or tested. Since initial construction of D.C. Cook (circa 1974), I figure this diesel has been tested - minimum - 300 times. I base this on a once per month test frequency over a span of twenty-five years."

If I have read this thread right, the part in question was installed backwards and is a relief valve...used to relieve the pressure of the fuel should it build up to an intolerable level. If your figures are right nucpwr, then there have been, what we in the Occupational Safety field call 300 near misses in the past 25 years...that would not, and should not, be an acceptable level of risk. I would say that God loves em....

Just my 2 cents...

SafetyOne a.k.a. Martha

-- Anonymous, July 01, 1999


Martha: We digress farther and farther from the 'AND Y2K' part of this group, but I'll add to the problem... If you have inferred from my posting that I think this faulty valve is not a problem at all, you have misunderstood. If something is not right, then it is wrong. It needs to be fixed. What this is NOT, however, is a conspiracy by the evil (read: nuclear) electric utilities like many on this thread would have you believe. As a safety representative, I'm sure your research into the nuclear industry has shown a safety record close to that of the neighborhood quilting club. The reason is that the acceptable level of risk is practically non-existant. This valve was not an acceptable level of risk; they are not going to take credit for this EDG until it is repaired. Do you see the bottom line there? It has worked for 25 years, but because it is not correct, the utility has placed itself in a 72 hour LCO. They will have to shutdown the plant because of this EDG that has worked correctly for 25 years.

NOTE: One of my previous posts references a seven day LCO. This is not correct. I can only assume that D.C. Cook has the same requirements as my plant, and those requirements state:

If one diesel becomes inoperable it must be restored to an operable status within 72 hours, or the plant must be in hot standby within 6 hours and in cold shutdown within the following 30 hours.

-- Anonymous, July 01, 1999


nucpwr wrote:

As a safety representative, I'm sure your research into the nuclear industry has shown a safety record close to that of the neighborhood quilting club.

this is a comment that defies a response. the mind boggles...

-- Anonymous, July 01, 1999



And yet, you responded. Prove me wrong, marianne. I'll point you to http://www.nei.org/library/facts.html

-- Anonymous, July 01, 1999

well nucpwr... i guess it all depends on how you define quilting party, right?

maybe yours are alot more exciting than the ones in pa dutchland...

they are known for their quilts though.

http://www.tmia.com/

-- Anonymous, July 01, 1999


Oh, they are, they are. Now, before Rick deletes this entirely useless (as pertaining to Y2K) thread, please point me to a forum where the pro/con of nuclear power can be debated.

-- Anonymous, July 02, 1999

"Martha: We digress farther and farther from the 'AND Y2K' part of this group, but I'll add to the problem... If you have inferred from my posting that I think this faulty valve is not a problem at all, you have misunderstood. If something is not right, then it is wrong. It needs to be fixed." ================= nucpwr - Yes, it did seem to me that you thought that since the generator worked, then everything was fine. But now that you have explained, I see that you are concerned...no harm, no foul. ================= "What this is NOT, however, is a conspiracy by the evil (read: nuclear) electric utilities like many on this thread would have you believe." ================= I refuse to get drawn into the "good vs. evil" debate over nuclear power. As a former construction worker who worked on the Wolf Creek plant in Kansas, I reserve judgement. ================= "As a safety representative, I'm sure your research into the nuclear industry has shown a safety record close to that of the neighborhood quilting club. The reason is that the acceptable level of risk is practically non-existent." =================== As for research into the nuclear industry, you are partially correct, their OCCUPATIONAL SAFETY record is among the best, and I use it often in my teaching to hospital workers as an example. The reason they (the nuclear industry) have so few injuries is due to the kind of work they do. The employees know that what they do is dangerous, and so are more careful. I compare that to healthcare workers, who have one of the highest injury rates of all industries. They don't see their work as dangerous. Now, when it comes to OPPERATIONAL SAFETY, I have no idea about that. It is not my expertise. But, even I can see that a near miss is a near miss. ============ This valve was not an acceptable level of risk; they are not going to take credit for this EDG until it is repaired. Do you see the bottom line there? It has worked for 25 years, but because it is not correct, the utility has placed itself in a 72 hour LCO. They will have to shutdown the plant because of this EDG that has worked correctly for 25 years. If one diesel becomes inoperable it must be restored to an operable status within 72 hours, or the plant must be in hot standby within 6 hours and in cold shutdown within the following 30 hours. =================== Question: Yes, the generator worked for 25 years. But, the valve in question is a relief valve. Did it ever HAVE to work in the 25 years of operation? What would have happened if it hadn't?

It is good to see that the plant is following the right course of action now that the problem has been identified. I believe that what the concern was all about, at least from my perspective, is that this went un-noticed for so long. It makes one wonder what else as escaped detection...?

I think that this is a valuable discussion, and I hope that it is not deleted. It relates directly, in my opinion, to Y2K, in that it points out that we humans are not infallible, and are capable of missing some things related to Y2K repairs...

SafetyOne a.k.a. Martha

P.S. This is my favorite quote, and I do believe it is appropriate:

"The significant problems we face will not be solved by the same thinking we were at when we created them."

Albert Einstein

-- Anonymous, July 02, 1999


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