Monday, October 5, 2015

Hanford And The "B" Reactor

The Hanford Nuclear Reservation was developed during World War II. It was chosen for several reasons, some of which was a good source of water, plenty of available electricity and a remote location. The Army confiscated the property, relocated the citizens of the town of White Bluffs. Soon a massive construction project was started. Reactors were built starting with the "B" Reactor. Other processing facilities were built to handle the products produced by the reactors. The whole purpose of the Hanford Nuclear Reservation and the reactors was to make Plutonium 238 for nuclear weapons. The "B" Reactor produced plutonium for the first atomic bomb exploded in New Mexico and the bomb dropped on Nagasaki Japan. Eventually plutonium production ended at Hanford and the reactors and processing plants were decommissioned. All the reactors except "B" were entombed in a structure and all the support buildings demolished. "B" was kept as a National Historic Site. The work being done at Hanford is now cleanup of the mess made during plutonium production.

A couple of months ago, I saw a television show where they mentioned the "B" Reactor tours. I knew about them a couple years ago, but circumstances got in the way of reserving a spot. But this time I got on the computer and reserved the last tour spot on September 29 th, the next to the last tour date of the season.

I decided I could make a day trip, so I was underway at 0445. With a breakfast stop at North Bend and a few Rest Stops, I was over Snoqualmie Pass and at the Richland reception center by 1000, well before the required checkin time. After a briefing and a short video, we loaded onto a tour bus and started north on Highway 240. Our guide talked continuously about the history of the area, the archaeological aspects of the area and a lot of other items. We entered the complex near the Columbia River and parked in front of the "B" Reactor. I was immediately shooting pictures without thinking that we had 2.5 hours there. 

The reactor was very interesting. It looked like it was shut down and the operators walked away. Equipment and furnishing were all in place. I was really amazed at the construction and the material schedule. I would have never thought that aluminum tubing would be used in a reactor! The "B" reactor is a graphite moderated reactor. The pressures and temperatures are quite low. Remember, this reactor was intended to make plutonium and was not intended to produce steam. Most of the plant was wide open. Some areas were still contaminated or radioactive. Barrier tape or physical boundaries kept everyone clear of hazards. Docents were there to give talks on the reactor operation. After 2.5 hours, we were back on the bus.

The bus took us back to the reception area, but this time we went through the length of the Hanford Site. We saw many of the entombed reactors and the remains of the old town of White Bluffs. We arrived at the Center at about 1530 and I was back on the road soon there after. This time I took a route that took me through Moxee, Yakima and home over Chinook Pass. It was a great drive home and I was home at about 2100.

Since I have been to Ground Zero in Nagasaki, this tour for me was like a "closing of the loop" in this historical event. Now I need to visit the Trinity site to complete my tours. The Trinity site and the "B" Reactor are scheduled to become National Parks in the future. Another reason for this trip was "Professional Curiosity". I just wanted to see how it was built and operated.

Here is a link for the B Reactor Tour Registration

 The reception center in Richland.

The "B" Reactor

 Hallway from the entrance to the reactor room.
 Warning board entering the reactor room.
 This is the front of the reactor. There are 2004 tubes. Each one has its own cooling water supply. The tubes are aluminum. The uranium fuel is encased in an aluminum tube and fits into the reactor tube with .080 radial clearance. There is only about 450 gallons of cooling water in the reactor at any time. Water is pumped from the Columbia River and after it leaves the reactor and goes through a settling pond and back to the river. Water temperature entering the reactor is about 55 degrees F and leaves the reactor at about boiling, 212 degrees F.
 This is the front of the reactor. Each tube is loaded with cylinders of uranium fuel and pushed toward the back. Sixteen spacer tubes were pushed in after the fuel. There was several feet of shielding material between the exterior and the graphite core. The fuel was in the center of the core for 60-90 days before the fission products made enough plutonium out of the uranium fuel. The areas around the edges might take a year before it was "done". When the fuel was ready for extraction, the reactor was brought to a low power level, the water secured, the tube cap removed and the fuel pushed out the back of the reactor where it drops into the water pit. One Docent (who was a reactor operator) said that exposure rates at the front of the reactor were not too high.
 Lets crank it up and make some plutonium!
 The control console.
 This clock in the control room is stopped at 1048, the time this reactor first went critical.
 The SCRAM (Safety Control Reactor Axe Man) button. There were two that needed to be pressed simultaneously.

Each of the 2004 process tubes in the reactor had a pressure indicator in the control room. If even one tubes pressure varied by more that 3 psi, the reactor would SCRAM. And a sign said not to lean against this board or it could SCRAM the reactor. Someone ought to warn this lady!
 Below this wooded grating is a water pit where the irradiated fuel is stored during it's cooldown period. The workers moved and handled the fuel with 20 ft long tongs.
 Placard showing the layout of the reactor.
 The Valve Pit where cooling water is circulated.
 Model of the graphite moderator and process tubes.
The train and casks that hauled the irradiated fuel to the processing plant. 

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