Chapter 1. Introduction and Background

My first real introduction to the Three Mile Island (TMI) accident happened on Saturday March 31, 1979. At Davis Besse Nuclear Power Plant (DBNPP) in Ohio we heard something serious had happened as early as the day of the event, March 28, and interest was high as it was a sister plant. Actual details were sketchy for the next couple of days, and mainly by watching the nightly TV news it became clear to me that something serious was going on. It was also clear from watching the TV news reports that conflicting information was being reported. Some reports indicated there had been radiation releases and also reports by the utility, Metropolitan Edison the owner of TMI, of no radiation releases. I also remember even hearing the words “core damage” first mentioned. It was also that Saturday, on a TV news report, I saw the first explanation using pictures of the system to explain the suspected sequence of events and it became clear to me the Pilot Operated Relief Valve (PORV) had stuck open. My reaction was gut-wrenching and I was also in disbelief that TMI did not know what had happened at Davis Besse. That evening I watched the Walter Cronkite news report. I sat there with total disbelief as he discussed potential core meltdown. Disbelief because if you were a trained Operator in those days it was pretty much embedded in your head that a core meltdown was not even possible; and here that possibility was staring me right in the face. It was also my first exposure to the infamous hydrogen bubble story. I had had enough Loss of Coolant Accident (LOCA) training to understand that some hydrogen (H2) could be generated during Loss of Coolant Accidents; after all we had Containment Vessel hydrogen concentration monitoring and control systems   installed at our plant. But the actual described scenario at TMI seemed incredible, except it had apparently happened. I would expect my reaction was the same as many nuclear plant Operators at that time. With the exception that the apparent initiating scenario had actually happened to me eighteen months earlier at Davis Besse and I just couldn't get the question out of my mind: “Why didn’t they know”?

Pretty much everything I’ve learned about how my event at Davis Besse relates to TMI I’ve learned well after the TMI event by reviewing all the published post-TMI investigation reports, e.g. Kemeny, Rogovin, etc. It’s all available as public documents, and those two primary reports were compiled by those respective organizations after thousands of hours of sworn deposition testimony from the key players. Some of the information in this document is also taken from the book The Warning, which is a fairly accurate, condensed technical representation of facts the authors gleaned out of review of the depositions taken by the two primary investigations.  I think the book facts are accurate, however when the author’s shift to a conversation tone, they tend to embellish fact for effect, but the fact is mostly correct. There are also passages in my section of the book on the Davis Besse event where the authors are obviously stating their opinion. My comment on that is that a Hollywood screenplay writer and a 60 Minutes producer are not technically qualified to judge my actions; they do however have the right to an opinion.  My section for the book The Warning was taken by the authors from information in my deposition to the Rogovin Commission. I know this is true, as I had personal phone contact with one of the authors at the time he was writing the book.

After the TMI accident President Carter charged the Kemeny Commission with their fact-finding task and to give recommendations. Rogovin was an internal Nuclear Regulatory Commission (NRC) investigation done by NRC, which in theory at least was supposed to accomplish the same thing. Both reports mostly agree, but by human nature Rogovin has some substantial differences. No organization can truly investigate itself, and some of that is obvious to me with years of hindsight and more information. NRC had an agenda, mostly pushing for changes they wanted to make to plant designs, organizations, etc., but also to deflect total blame for the TMI accident from the NRC. I was such a small piece of the total puzzle at the time I couldn't see everything clearly then. But I do remember being puzzled at the time by the line of questioning going on in my deposition to Rogovin. They just didn't seem to be asking the right questions. I had legal representation (a lawyer for Toledo Edison Company, the owner of DBNPP) during my deposition, and I had been thoroughly instructed not to volunteer anything, so I just "got through it."

What was never obvious to me until well after TMI and reading all the reports, was just how concerned Babcock & Wilcox (B&W, the Davis Besse reactor vendor) was about the Davis Besse event. The same is true about concern within the NRC as the event actually got discussed at the level of the Advisory Committee on Reactor Safety (ACRS) twice before the TMI accident. A passage from Kemeny Report is sobering for me personally:

"A B&W Engineer had stated in an internal B&W memorandum written more than a year before the TMI accident that if the Davis Besse event had occurred in a reactor operating at full power, 'It is quite possible, perhaps probable, that core uncovery and possible fuel damage would have occurred'."

 

Put yourself in my shoes reading this. This conversation is going on about eighteen months  prior to the TMI accident, but I only become aware of this discussion quite awhile after TMI when I read about it in the Kemeny Report . The B&W engineer is Bert Dunn and he is the expert on this stuff, and he's saying I could have melted the core if we had started at higher power (like TMI). My feeling is anger when I read this. Couple this with his statement in the Rogovin Report that “he had concern that the operators had terminated the high pressure injection system prematurely. He pointed out that he could develop scenarios in which the operators could have engendered serious consequences by securing high pressure injection.” More anger, if I had been in this conversation I would have said "You guys did this to me; put me in this position!!! With your wrong training and bad procedures... just what else have you messed up because you haven't even looked at it?"

Here’s a totally academic question; what if Bert Dunn had actually been curious enough to simply ask me why I turned off the High Pressure Injection pumps? After all, we knew each other, had interacted in training sessions, etc., I was quite literally at the other end of a phone call. And it even gets stinkier after this, Dunn works in the B&W Safety Analysis Group, but Joe Kelly, to whom Dunn’s question sunk in, is in the B&W Plant Integration Group and this type of thing is directly within his area of responsibility. After another Davis Besse plant event about a month later also concerns Joe Kelly, he writes the infamous “Smoking Gun” memo, internal to B&W, asking “Are we sure we’re giving our Operators the right instructions on securing High Pressure Injection?” That memo is much discussed in both the Kemeny and Rogovin Reports and also key in the ’82 civil law suit where TMI sues B&W for $4B. That memo basically gets lost in the administrative morass of the large B&W Corporation after some internal B&W debate.

If you think this might create a confusing (e.g. catch-22) situation for the Operators, about just exactly what and when, to do with the High Pressure Injection flow, after initiation from a multitude of potential causes, just imagine the confusion that was caused at B&W internally by the Kelly memo… so much so apparently that he only got one response. The memo went to 7 people within B&W but Kelly only received one response.  That response was from Frank Walters in the Customer Service group. Walters’ hand written memo stated the Operators at Davis Besse responded correctly in view of their training. He further stated during the incident at Toledo Edison there was no loss of coolant of magnitude and, in Walters' opinion, the Operators would not be right to place the Reactor Coolant System in a solid condition every time the High Pressure Injection pumps initiate.

The Rogovin Report also states:

“Before writing this memo, Kelly talked to the simulator instructors at B&W and they stated that they did not understand why the operators reacted as they had. They stated that the operators had not been trained to secure high pressure injection unless reactor coolant system temperature had stabilized, reactor coolant system pressure was increasing, and pressurizer level was in the indicated band.”

Not only is this Simulator Instructor statement untrue in an actual Pressurized Water Reactor, it is about a physical impossibility in a Small Break Loss of Coolant Accident. The Reactor Coolant System temperature will continuously decrease when High Pressure Injection is pumping water into the Reactor Coolant System, the Reactor Coolant System pressure response is dependent on the break size, and of course they were teaching “the Rule”; never let HPI pump the Pressurizer full. Since the B&W training Simulator Pressurizer level responded backwards to the actual plant event, the result will always be High Pressure Injection termination by an Operator in the actual event.

Note that this is not the last time this Kelly – Simulator Instructor discussion will occur. It happens again less than two weeks after TMI. Only this time there are players present from all the B&W plants, and a slightly different discussion outcome occurs. Yours truly goes “postal” in the middle of the meeting about just who is training Operators to do what, on the B&W Simulator not fifty feet from that meeting room.

With that background you can move to September 24, 1977 and the narration in The Warning. For the most part it is basically accurate, but they only had their reading of my sworn deposition to the Rogovin Commission to go by, and they are after all trying to write an impact book. So if something didn’t get asked by Rogovin, it wasn’t in my transcript. There are two key points missing in the book discussion, or at least under explained, that bear directly on the successful outcome for this event. The first one is that sometime within the 10-15 minute time interval I made the realization that something was going on that I had not been told about in any of my previous nuke experience or training. So I realized I was going to have to figure it out using my own intuition. I remember one of the interviewers (non NRC) after the event asking me if our Loss of Coolant Accident Emergency Operating Procedure was helpful during the event. I told him I wasn’t using it. He then asked me why I had (or possibly thought I had) overlooked it. I said I didn’t overlook it; I had eliminated it because my Pressurizer was full. The damn thing seemed to be making water not loosing it!

The problem I was having, especially early on in the first 10 minutes, was one of time management, as the incessant constant new alarms, and automatic system actuations, that kept coming that had to be dealt with, distracting me from getting what’s known as the “big flick” on the Reactor Coolant System conditions. Another small one, which may not seem significant to a non-Operator, was the constantly recurring blaring of the alarm horn, which was especially loud and obnoxious, by intent. It literally kept me from concentrating, so I assigned an Auxiliary Operator to the horn “silence” button, telling him to immediately silence it every time it sounded. The second key point was my reaction to watching the Reactor Coolant System pressure response (to the unknown stuck open PORV) as it continually dropped from about the 1 minute mark post reactor trip (shortly after the Safety Features Actuation System Low Reactor Coolant pressure trip) to the point it bottomed out just below ~900PSI in the 8 to 10 minute post trip time frame. What really sunk in to me at that moment was that we had not done anything to stop it from dropping (as much as I wanted to see it stop dropping!) and that point sunk in deep enough that a short time later I came back to it and figured out why it had stopped its constant decrease. The truth is before the Reactor Coolant pressure stopped dropping, I actually had the thought during the time frame it was approaching ~850PSI that the Core Flood Tanks were going to dump, and then I’d really be “in for it” later.

Aside

One of the problematic areas I still have about this event and to a greater degree also in the TMI event is how Monday Morning Quarterbacks will reach a conclusion of Operator Error about one small piece-part of a complicated multi part problem. I think this is in part because they look at their single assigned investigation piece-part in total isolation of the whole, while sitting at a desk, dissecting tons of computer generated moment-by moment data available to them in the format of a high speed data recorder.

End Aside

But this particular response is only an Operator error in hindsight; if virtually everybody in the nuclear industry had simply “assumed” Pressurizer level went down on all Loss of Coolant Accidents, and further that decreasing level response is what the training simulators of that era showed also, why would any Pressurized Water Reactor Operator think differently in the heat of battle? After all, the bottom line purpose for any type of simulator training, is to pre-condition the “trainee” to respond correctly to events they are never likely to see in actuality. In the real world with a total machine as complicated as a large commercial nuclear power plant, it is never possible to anticipate all the possible permutations of minor failures cascading on top of each other, so that you can train the operator to “cookbook” anything and everything. The best you can strive for is to give the operator the correct whole package of fundamentals, and some correct pre-conditioning to anticipated and designed for events. The operator has the responsibility to learn that whole plant, in the field, to the extent they can visualize the whole package connected to the instruments and controls available in the control room. Then when the “crap hits the fan”, as Murphy says it will, and an event occurs which is totally unique to what has been anticipated or specifically trained for, the operator (and his team) must put that whole fundamentals package to use for a successful outcome. In the operator examining world this is referred to as “think on your feet”, and it is an integral part of any good operator training program to challenge prospective operators with non “cookbook” events.

But what happens when something in the Operator’s whole package of fundamentals has been presented erroneously because it was never looked at analytically? This led to Emergency Operating Procedure guidance that was basically flawed for that event because of the “guess” that a hole in the steam space of the Pressurizer would cause Pressurizer level to decrease like a Small Break Loss of Coolant Accident in any location in the water space of the Reactor Coolant System. Then add to that, the Pressurized Water Reactor training simulators of that era (both B&W and Westinghouse) were actually forced (programmed) to make that wrong guess actually display the result of the wrong guess; that the Pressurizer level went down on a stuck open PORV. It is possible, although I have no actual knowledge of such a fact that during a past B&W Training Certification Exam scenario an actual examinee could have been given a stuck open PORV casualty. And for whatever reason, just lost control of High Pressure Injection throttling during cool down, and with an additional failure inserted for the block valve failure, etc., the reason doesn’t really matter, but the examinee let the Pressurizer level get off scale high; it would be an undisputed exam failure. It is an indisputable fact that letting the Pressurizer level go off-scale high due to High Pressure Injection flow during a B&W administrated Certification Exam would result in an exam failure result.