ACCIDENT AT THE THREE MILE ISLAND NUCLEAR POWERPLANT WEDNESDAY, MAY 9, 1979 U.S. HOUSE OF REPRESENTATIVES, COMMITTEE ON INTERIOR AND INSULAR AFFAIRS, Washington, D.C. The committee met at 3:40 p.m. in room 1336, Longworth House Office Building, Hon. James Weaver presiding. Present: Representatives Weaver, Carr, Markey, Kostmayer, Vento, Marriott, and Cheney. Staff present: Messrs. Myers, Burnam, Terrell, Reis, Scoville, Rogers, and Sadleir. Also present: Messrs. Mattson, Stello, Eisenhut, and Combs. Mr. WEAVER. Gentlemen, thank you very much for coming. Mr. WEAVER. Thank you very much. What we want to do here is have an informal review of what happened. [Discussion off the record.] Mr. WEAVER. I would like to keep this informal. Let us talk about the details of what happened at Three Mile Island so that, as we compile this information, perhaps a picture will begin to form in the minds of the members of this committee and we will be better able to analyze and deduce from that. I would like to ask Dr. Myers to commence his line of questioning. If any of you have anything to offer or volunteer, that would be fine. Dr. MYERS. Do you think it would be useful if they went through the chronology as they best understand it now, as opposed to the way Mr. Denton did it the other day where he was sort of relating it as he had experienced it? Mr. WEAVER. That is an excellent idea. Dr. MYERS. Darrell Eisenhut has been briefing the Commission on this. Darrell, I do not know who would want to do it or who is most familiar with it. PANEL FROM THE NUCLEAR REGULATORY COMMISSION CONSISTING OF: ROGER MATTSON, DIRECTOR, DIVISION OF SYSTEM SAFETY, OFFICE OF NUCLEAR REACTOR REGULATION; VIC STELLO, DIRECTOR, DIVISION OF OPERATING REACTORS, OFFICE OF NUCLEAR REACTOR REGULATION; AND DARRELL EISENHUT, DEPUTY DIRECTOR, DIVISION OF OPERATING REACTORS, OFFICE OF NUCLEAR REACTOR REGULATION Mr. STELLO. Let me make some opening comments first. In order to truly have an accurate list of facts exactly as they occurred during the accident, you are going to have to go back through all the records, all of the strip charts, pull them together, interview all the people to get their best recollections, and pull together the best sequence of events you can based on that information. That is being done right now. My understanding is that that actual identification of the factual chronology will be available about next week. That is going to represent the best information we have to identify that sequence. Other than that, I think it is going to have to require very crude, rough ideas based on individual recollections, and like the piece of paper that you have now, which is GPU's recollection and identification of the sequence of events based on their record search. But anything we do say we are subject to refinement and identification of the facts based on the investigation that comes out next week. With that, Darrell, maybe you can highlight. Mr. EISENHUT. Yes, I was going to make the same kind of comment. Mr. Stello, of course, just returned from the site yesterday. I guess you and I were contacted early on the 28th about 8:30-8:45. We have been proceeding in parallel since then. We first came back together yesterday physically to where we can be working trying to put the pieces together. Mr. WEAVER. I would like to ask you: At what hour of what day did you first get on site? Mr. Eisenhut. Mr. EISENHUT. I did not go to the site. Mr. WEAVER. You did not. Mr. Stello did. Mr. Mattson, you were not at the site, either? Mr. MATTSON. Yes, I was on the site. Mr. WEAVER. Mr. Stello, what hour of the day did you arrive at the site? Mr. STELLO. We arrived on Friday, I guess about 3 o'clock. Mr. WEAVER. Mr. Mattson? Mr. MATTSON. 11 a.m., Sunday, April 1, through Easter Sunday. Mr. WEAVER. You were all working at NRC headquarters in a coordination role on this? Mr. MATTSON. When I was not at Three Mile Island, I was working on Three Mile Island from Bethesda; yes, sir. Mr. WEAVER. How about reciting, beginning with Mr. Mattson what happened as far as your knowledge goes and what your role was in it-I mean what you saw. Why do you not just begin reciting to us? Mr. MATTSON. Maybe it will help kick off the chronology sort of thing you want to hear about. Mr. WEAVER. When did you first hear about it? You can start of with that. Where were you and what was happening? Mr. MATTSON. I was in my offices on Wednesday, the 28th. I tried to reach Mr. Denton that morning; got hold of him. Heard Mr. Case Mr. Stello, Mr. Eisenhut had gone to the emergency center. I believe you had gone that morning, Darrell; is that right? Mr. EISENHUT. No, I did not go early. I was running the other end Mr. MATTSON. That there had been some kind of event at Three Mile Island. Mr. WEAVER. What time was this? Mr. MATTSON. Midmorning, Wednesday, the 28th. Mr. WEAVER. Nine to nine-thirty? Mr. MATTSON. Probably closer to 10 o'clock. It would not be normal for me to be called on an operating reactors kind of problem. Mr. Stello is the Director of the Division of Operating Reactors. I am Director of the Division of System Safety. I believe I was talking to a secretary so I knew I was not getting firsthand information. I asked her to have Mr. Denton talk to me later whenever he knew what was going on. He did that later in the day and said that the people were working hard in the incident center. He planned to go on over a little later in the afternoon and that I should keep working the five-plant shutdown. You may recall we had been down talking to you a week or so before. The first priority for my day, that day, was working on the seismic analysis of the five plants that were down. I, in fact, stayed on that work until about 2 o'clock Thursday afternoon, at which time I went to the incident center to get Mr. Stello to sign a piece of paper having to do with the five-plant shutdown. From that time on, I have been working Three Mile Island. Mr. WEAVER. Mr. Stello, when would you say you first heard-where were you and what was happening? Mr. STELLO. I got to work about 7, 7:30 that morning. The first phone call I received. I think, was identifying that there had been an incident at Three Mile Island, probably near the hour of 8 o'clock in the morning. Mr. WEAVER. From whom? Mr. STELLO. Mr. Moseley. Mr. WEAVER. Who is Mr. Moseley? Mr. STELLO. Mr. Moseley is the Director of all of the operating reactors in the Inspection and Enforcement Division, who called and activated our operations center. As part of the standard procedure for activation of that center, he is to call the various members, and I am one of them. So he called to notify me that the center had been activated. Mr. Eisenhut was in the office with me that morning. I immediately called Mr. Grimes, since he knew there had been a release of fission products to the environment. I told Mr. Grimes to immediately go to the center. I asked Mr. Eisenhut to set up the various people that would be needed to understand Three Mile Island in his office, and as soon as I gave him that word I immediately left to go to the center. Mr. WEAVER. The center is Bethesda ? Mr. STELLO. It is in Bethesda in our headquarters Office of Inspection and Enforcement on East-West Highway, some distance from my office which is on Norfolk Avenue. Mr. WEAVER. How many times has that center been activated? Mr. STELLO. I can recall, I guess, three occasions. Mr. WEAVER. Three occasions in the past? Mr. STELLO. This being the third. There may have been more. Mr. STELLO. Since its existence. Mr. WEAVER. Which is? Mr. STELLO. About 3 years. Browns Ferry fire being, I think, the first one that I can recall. Upon arriving at the center, I tried to obtain some information, understanding about what was happening both to the reactor and to the environment. We had a communications system set up, where people who were in the control room at Three Mile Island were communicating factual information as to what was happening to the people in Bethesda. We were doing various kinds of studies, trying to understand the process that was going on in the reactor as well as what was going on in the environment. Our immediate effort was probably heaviest in terms of understanding what was happening to the reactor, since the normal processes that you expect if you have a very bad accident in the reactor is one where the primary envelope has been breached and the water and fission products are emptied into the containment and environment. Here we had a clearly different situation. We had an intact primary system with significant release of fission products. Early throughout the day it became apparent that conditions had developed where the core was being badly damaged. Mr. WEAVER. This is still on Wednesday? Mr. STELLO. I am now giving a very general picture of Wednesday, rather than specific hours. Without going back through the actual tapes Mr. WEAVER. Surely. Mr. STELLO [continuing]. Refreshing my own recollection with respect to hours or times, I could not. But throughout the day, the clear impression was created that there was significant damage being caused to the core. The principal reason-I am giving you a personal feeling I cannot remember whether the group truly felt this way or not. Mr. WEAVER. I understand. Mr. STELLO. I will try to come back Mr. WEAVER. I have to leave. Dr. Myers, proceed. I will be back. Mr. STELLO. The reason for believing you had significant damage was the fact that we had a clear indication that there was superheated steam coming out of the reactor vessel. The only way you can, in fact. get superheated steam out of the vessel is to have the core uncovered. And the core, just from recollection, was uncovered for substantial periods of time throughout the day, which left me with the clear impression that significant damage had occurred in the core. Dr. MYERS. Did you at the time have a sense of what you were thinking of by significant damage, whether it was as it turned out to be. Were you thinking at the time it might be as extensively damaged as it later developed it was? Mr. STELLO. My initial reaction was that considerable failure of the fuel had occurred, with large numbers of failed fuel rods. And that the potential for oxidation, metal-water reaction, was clearly |