HANFORD REACH > Oral Histories

Eugene Woodruff

On the site, they had a neat way of disguising what we were working on: they called it “non-metallic materials.” It was the graphite room...

I started in '52. I was a graduate of Washington State in geology; I came here in '52. It was in the fall I applied, and of course right away they wanted an application for security clearance. So that took about three months. And in December I got a call that said they wanted me to come to work. So on January 30th 1952 I came to work. And they were sort of debating about who was going to end up with me, Metallography or Graphite. So I ended up in Graphite.

And my first job was to measure thermal expansion of graphite with an interferometer, which is kind of a blinding affair. You use one eye to watch little fringes moving across, as you heat the sample up. And at the end of the day, the two eyes don't coordinate too well. So anyway, I did that for awhile and the fellow I worked for, he was running a program that irradiated graphite in the reactors out here measuring the thermal and physical properties before and after irradiation to find out what the damage was from being exposed to neutrons. He was measuring the length of samples before and after irradiation with a micrometer, and I would take the data down in a notebook.And then he left, and I inherited his job. I had meantime written, co-authored, a report about the thermal expansion. And some of the powers that be decided that maybe a laboratory assistant wasn't the right job for me and they promoted me to junior engineer. Anyway, I got promoted. So I took over the irradiation of graphite samples, and I was the guy running the micrometer, measuring samples, irradiated and un-irradiated.

Graphite was a peculiar beast, lots of different problems. The big problem was dimensional stability. When they first started up, the reactors “grew” rapidly. And they even shut one down, because of that. When they designed the reactors they had no idea what the behavior would be. It was kind of a surprise.

The physical dimension of the graphite stack was growing and that's what was pushing the top off of the reactor. All I was doing, measuring the length of the samples, was determining what that growth rate was.

And it turned out that damage in the graphite at low temperatures created what was called "stored energy." Expansion of the graphite was because because carbon atoms got knocked out of their original locations in the lattice, and they ended up between layer planes, and that pushed the layer planes apart; that’s what the growth was all about. Well this expansion, this change in dimension and the dislocation of those carbon atoms, created a situation: if you raised the temperature rapidly, you would anneal it rapidly, and the temperature would escalate very rapidly, releasing all of that energy, by annealing. So that was a concern here, because of the early operation at low temperatures, and increase in the stored energies.

And they found out that irradiating at very low temperatures increased the growth rate of the reactor. If they raised the temperature of the irradiation it annealed out some of this growth, and the growth rate was reduced. And so the way to reduce the temperature was to raise the power level. And everybody was happy about raising the power level.

One of the things we did to monitor the reactors was take samples and send them to a place where they could measure the stored energy.
I think I had that program two or three years, and I would sample each reactor about once a year.

When we sampled, took the cores out of the reactor, we were on the front face of the reactor, and we were suited up in double-layered canvas and all covered. To do that job we were well protected. We had test holes; we’d go in the side of the reactor, we’d go in to take samples... We would suit up with all the paraphernalia. I don't recall wearing face masks, with air; I don't recall doing that with any of the jobs I was on. Anyway, we were pretty well covered.

And so we had a method to go in and cut cores out of the graphite in the reactor with a device that screwed in and took a little core out of the bar of the graphite. I inherited that program eventually, to go out and take those samples. During an outage, when the reactor was shut down for a fuel change, to get a core of graphite the first thing was to push the fuel out, and push the tube out, it was an aluminum tube. So then you had an open hole in the graphite, which you could put a tool in, we call it a core board. You could lower it down and take the sample out, and then pull the device out again. And we’d take maybe three or four cores, [at] different locations. Around the fringe of the reactor it was running colder and we were sampling the fringes of the reactor, the graphite that ran colder, to find out what the stored energy was. It scared a lot of people, when we would start to pull the core out. We had monitors with instruments; they were very excited when we were doing it. But it actually wasn't very hot. The graphite was pure, the core graphite in the reactor. So it was not very hot at all; it was something we could handle easily.

And of course those measurements indicated that we didn't have a real problem with stored energy. But if it did indicate that say in the fringe it was getting to the point it might be a problem, what they would do was raise the temperature and anneal the stored energy. You could anneal it out, if you raised the temperature very slowly, without getting a sudden release. And so that's how you would take care of that problem. We never had to do it, but people at Brookhaven they did have those problems, and they did anneal a reactor, there.

And I became interested in metalography, doing microscopy. And we became interested in doing electron microscopy on graphite. The technique developed out of Hanford was to replicate that surface for using electron microscopy.

The technique we used, you could look at a lot of different graphites without really destroying [them]. You’d polish the sample, then you’d oxidize it a little bit, and then you’d take a replica, and I remember we did that with a sample... Took a film, and then irradiated the sample, and took a film after, to look at it before and after the radiation. So, there’s all kinds of games you play...

That technology of looking at graphite became of interest. And one of the managers in the department I worked in, they had contacts with other people in other sites, and he had contacts at Los Alamos with people working on a Rover, proposing rocket fuel. They had problems with coating that fuel; the fuel was a graphite matrix. So they decided to see what electron microscopy could do to add to the picture of what was gong on.

Graphite is produced at 2,700 to 3000°C, so if you put it in an inert atmosphere, you can take it to those kinds of temperatures and it survives; a lot of materials don’t survive. So nuclear rocket fuel was of course operating at very high temperatures, the fuel itself was uranium oxide or carbide in little spherical pellets, with graphite around it, in a graphite matrix. The graphite was made from petroleum coke and coal tar...

So I spent some time looking at fuel for the rockets. The fuel was made in Los Alamos, and another outfit in Oak Ridge was making it. So I traveled back and forth to those places, looked at their fuel... That was interesting. I got to do a lot of traveling between Oak Ridge and Los Alamos, and I became acquainted with the electron microscopist at Los Alamos. And he used a different technique for looking, but we traded trade secrets...

Now in the early ‘60’s... the Mid-Columbia Archaeological Society got permission, a permit to excavate a Chiawana site on the Pasco side of the Columbia. And so we excavated two or three different locations along that side of the river, that took two or three years. Then we moved to the mouth of the Yakama river, they had uncovered some bones... And so we excavated a site there. And the grad student got permission to survey the Columbia River for Indian sites. They had clearances so we could go out on weekends. And so we surveyed roughly from the 300 Area, the lab area, just inside, all the way up to Vernita, where you cross the river. And I think there were something like two hundred sites that we surveyed. That was interesting.

We actually excavated on Locke Island. We got in trouble… Before we excavated, we had to get rid of the tumbleweeds: it was full of tumbleweeds. So the way to do that of course was, put a match to it. Trouble was, the wind was blowing... So we burned the southern end of Locke Island... We got kind of in trouble...

One late winter and spring, I spent my days walking the banks on the west side of the river, all the way from 300 Area up to the lower end of Hanford Townsite. And we worked the Area, a quarter to a half a mile in. We walked back and forth, back and forth, surveyed that whole area. And there were of course Indian occupation sites along there, and Chinese gold-mining sites, and more exotic sites where there was equipment left behind, where they had mined gold. They were mining in the river, they were using the gold that was deposited in the river, that's what they were after. We could see evidence of that. That was kind of interesting.

And along the way, one of the other survey members was the son of Rex Buck: one of his sons.

Every reactor had a rail line into the reactor, and this was to carry the casks; on the flat cars, they had casks... Anyway, the fuel element went into those casks, and then it was carried over to the Separation Area, T Plant, and that's where the plutonium was extracted from the fuel... And it left the area in the middle of the night on trains. I lived down by the lower end of town, and I could hear the trains go by. I didn’t know what it was, but that’s probably what it was: it was carrying the plutonium. There’s a red line right here that goes down, and connects with the other terminals over in Pasco, and the rail lines, that go all over.

But it’s interesting, you talk about exposure: a lot of the places that I visited, like Oak Ridge and Los Alamos, those jobs, some of them were classified and some weren’t, but I had no problem interacting with those people. We all understood what was classified and what wasn’t… It was just that, in the early days, you just didn’t talk about work.

And my wife, soon after we get married, the summer after I started work here in ’52, she applied with the AEC, the Atomic Energy Commission. And she got a job with the assistant director as a secretary... And she didn’t talk about her work, and I didn’t talk about mine. It was just understood, it was just a natural thing… We just lived that way.

I have a book of mineralogy; it’s called “Dana’s Mineralogy.” It’s got all the minerals in there, and descriptions of them. And there's a page in there for graphite. In my old Dana book there’s a lot of penciled-in numbers. Guess what those numbers are? Combinations… for safes. We had to change combinations about every six months. And I’d get a new combination. I’d go to graphite, write it down, so I wouldn’t forget it…