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Paul Vinther’s Interview

Manhattan Project Locations:

Paul Vinther arrived in Hanford in 1950 where he worked as a physicist and reactor operator. Vinther discusses, in detail, DuPont’s safety philosophy as well as many of the safety measures put in place to protect workers at the plant. Vinther also discusses the impact of nuclear radiation on the wildlife and the various tests conducted to measure the environmental impact.

Date of Interview:
September 1, 2003
Location of the Interview:


[Interviewed by Cynthia Kelly and Tom Zannes.]

Paul Vinther: I’m Paul Vinther. P-A-U-L V-I-N-T-H-E-R.

I have a first name, Alvin, but never went by it so everybody knows me as Paul. And I first came to Hanford on June the 26th, 1950. I remember that vividly because that was the day after the Korean War started. And I’d been in the Navy, went back to college, and came down here for a job, and at that time GE was running the plant and we were known as “tech grads.” 

We’d have three months’ work in one area and three months’ work in another area and I did a couple of those, and then had a chance to work in the reactor areas. And the first job we had was what we call “area physicist.” That job was to utilize the equation that they had developed for computing what the xenon content was when you’re running the reactor.

[Pause to lose paper in his hands.]

Vinther: And so what we had, we had mechanical calculators like an old Friden and old March—Marchant calculator. And if the reactor went down, we then would take the equation, depending upon how long the reactor had run, blah, blah, and so forth and determine when it could restart again. It would take, perhaps, anywhere from twenty-two hours to thirty-two hours, depending upon the previous operating time. They could not restart if they shut down permanently. I mean, on a planned basis for that length of time, so on a planned outage they know they have a certain amount of time and they would plan their work, maintenance work or charge, discharge, or this sort of thing and that was the major task that I had. 

Also, as a physicist, we would come into the control room and we would help the operator adjust the control rods. As you know, you had to have so many control rods in to control the fission process, and maintain power level. But if you didn’t do anything you’d have sort of a cosine distribution of power generated in the tubes and the center tube would be the one that’s the hottest and that would be the limiting. If you could kind of flatten it out so that you had more tubes up at their limits, you could get more power level out of it. So that was part of our other task, was to determine what we could do to help increase power. 

When I first came on the plant, they were running at the design level of 215 megawatts and—but the Cold War had just started, and the push then was to, “What can we do to raise the power level to make more product in shorter period of time?” And DuPont had designed the plant, so over-designed it, that we were able to raise power levels significantly. 

We sort of probed it a little bit. We’d raise, perhaps, fifty megs and run it for a while more and we’d get up to 300 megawatts and then maybe go up another twenty-five megawatts and so forth like that. And then ultimately, after the 558 project where they increased the water flow through the reactor, the plants were running at 2,000 megawatts. So that’s a significant thing that DuPont had designed into the plant, to be able to run at that particular level. 

The other thing that was interesting—that GE did try to adopt the DuPont’s philosophy of safety. Safety was the first thing. If you suspected there was a problem, you didn’t go through with it, you stopped it and you did the right thing. And I remember our safety engineers were always running around making sure people were doing the right thing. 

Then in my—in our work as we were developing here, sometimes we would have a fuel failure. There’d be a failure in one of the fuel elements in a process tube. And if it failed, you’d get a lot of radioactive readings in the rear and you don’t—did not want to run with that, so the plan was if it would go quickly, we would perform what was known as a “quickie” discharge. They would know which process tube it was, and from the control room they could tell from the panel board what the problem was, from the rear reading. So what they would do, they get everything lined up with crews in the front, crews in the rear, and they would SCRAM the reactor, shut it down. 

The people in the rear would go in, they would identify the tube, take the cap off of it—after they lowered the water pressure—take the cap off of it, and then get out and tell the front crew, “It’s all clear,” and the front crew would then take a rod and so forth and they would push that fuel out. Then they’d go back in and cap up the tube and we’d try to get going again. If you could do it within fifteen or twenty minutes, you did not have to stay down for this twenty-two, twenty-four hours. You could recover. And so that was a real production gain if you could do that, but everything had to go right. If there was a stuck tube and jammed in there, no way could you do that sort of thing.

The other thing we learned in our work was to—when we started up the reactor, the nine rods— you didn’t have an awful lot of poison in which to control the thing as you started up the xenon that you had in the reactor was being burned out before being built up again, and you’d run out of rod. You’d get up to power level and you run the control rods in and then you’d have to say, “Well, we’d better—we better shut it down or—put some poison pieces in it,” or something like that. 

Well, we developed what we called a “quickie” startup. We’d get up and going and then we’d SCRAM the reactor, shut down for a few minutes. And at that time the xenon had been building up would help a lot and then we’d restart again and we had enough control rod to keep the reactor starting up and getting to power level. That was kind of fun. 

As a physicist’s job you were always on call. If the reactor went down you had to tell them when they could get going again. So we always had somebody on duty, at all times. If the plant went down, they’d be able to calculate what the xenon situation was, and that’s the main thing that I remember about the plant.

What about these concerns about the environment?

Vinther: I think it was initially, it was a DuPont concern, where their physics group, which was basically located in 300 Area—the headquarters anyway—and they were—the government interested also. What would be the effect of these plants on the environment? On fish? On animals? On fauna? The whole business. And so they set up a farm over in 100-F area. And they would run, say, river water into tanks where they had fish growing and living, and then measure to see what intake those fish were—would take from the water because F area was the furthest downstream reactor and like B area was the first upstream reactor. 

And as they—since these reactors were single pass machines, water would come in the front, go out the rear, go into a holding basin and then go back in the Columbia River. So if you had any contaminants you’d collectively get strongest down near the F reactor, so that’s where they would pull water out of the river and test animals and so forth with that. And that was—I guess they had all sorts, from pigs to fish to monkeys, and I guess they ran that for quite some period of time until they started shutting down the reactors and pulled all of that sort of study back in the 300 area.

What other things do you associate with DuPont’s reputation?

Vinther: The people felt that they had done a tremendous job. I mean, in building the plant, establishing safety regulations, and training for people as best they could to perform a task. And GE people also tried to do that. You had a lot of special classes in leadership and on evaluation, risk-taking and so forth like that. So that was very important, that we carried on that particular function. 

And of course people working here were always trying to find ways in which to improve: instrumentation was improved, the way we handled the fuel, and so forth like that. The interesting thing on charge—discharge was that the—of course the fuel would be pushed out of a tube, dropped into a basin, and their operators would have twenty-foot tongs that would pick up the fuel and put it into a bucket. And they were—the buckets—square buckets were made so that you could align these fuel pieces up inside in a special pattern, and when you got up full to the top then they would go in and weigh that to make sure they knew how many fuel pieces they had, because we wanted to make sure we knew where every spent fuel was and that we didn’t lose or miss any. 

And it was very important that they do that. So that was part of—when the reactor was running the operators would be in the storage area with these long tongs picking up fuel, storing them. And the buckets were handled by a special yoke that went up through the floor. They had a slot in the floor so you could move it up to a rail so you could hook onto a bucket with this mechanism and move that bucket over to some other spot and dump it down and let it cool. And so after a certain period of time cooling then they could take it and load it into rail cars to be shipped to 200 area for processing.

[Tape switch.]

What precautions were taken to protect workers?

Vinther: The important thing is, DuPont set up in the early days was protection of workers that were here. And it was very vital that people be properly trained and also so they wouldn’t get normal accident problem. But also to control the exposure that they would take because in working in the rear face, in particular, or in other areas near the reactor, you would get radiation exposure and they put a limit on how much exposure they could take in a week. And if the—you exceeded that limit then you could not go into a radiation zone and that, to a lot of operators, was a fact that if they were going to work any overtime they had to have the exposure to be able to go in and work and if they used up the exposure, that was it for them. 

And besides that, everybody was very much interested that you go in to do a job, you did it and you got out of that zone as quick as possible. The radiation monitors, for example, would be set up to go in where a man was going to work and say, all right, you go in, you measure it, and he says, “You can be in here for twenty minutes,” for example. And so the fellow would have to go in and they would monitor and they’d have a time keeper outside to—in a clean zone with communications and watch him very closely at the time limit. If that was it [clap] you’re gone. And he was out. 

And people were very stingy on how they used their exposure. And that was the big thing, other than the normal manufacturing kind of, industrial problems that you might run into.

What this a successful approach to protecting their health?

Most of the people who worked here were very confident of what was happening, that they were under proper control, that they were not asked to take dangerous steps, unnecessary steps, and people were very proud.

Of course, when I came in in ’50 we knew that the bomb had been developed here and so forth. And they were very proud, a very patriotic group of people. And they were willing to go in there and do—go the extra mile. And we feel that DuPont started that particular process.


Copyright 2012 The Atomic Heritage Foundation. This transcript may not be quoted, reproduced, or redistributed in whole or in part by any means except with the written permission of the Atomic Heritage Foundation.