Idaho Falls

ADVANCED TEST REACTOR | SCITECH n IDAHOFALLSMAGAZINE.COM 53 The Advanced Test Reactor (ATR) was built on the U.S. Department of Energy's 890-square-mile site 50 years ago, in 1967, when the president's initials were LBJ, Vietnam played out on the eve- ning news, a left fielder nicknamed "Yaz" won the American League Triple Crown, the Doors played "Light my Fire" on the Ed Sullivan Show, and McDonalds introduced the Big Mac. Much has changed over the last five decades. But ATR remains a unique and remarkable place that has enhanced the nation's national security while helping teach the world much of what it knows about nuclear energy. The truth, however, is that a machine is only as useful as those who maintain and operate it, and as memorable as the creative spark from which it emerged. Let's begin there. Origins In the nearly seven decades since the site, now known as Idaho National Laboratory, has operated, 52 nuclear reactors have been built. The Materials Test Reactor (MTR), constructed in 1952, and Engineering Test Reactor (ETR), built in 1957, played impor- tant roles in the development of the Nuclear Navy and emergence of nuclear energy. Valuable as they were, these facilities had limited capabilities. As the Cold War accel- erated, nuclear fuel became more complex. The Navy needed to test full-scale fuel ele- ments, not just samples, and it required the results of those tests more quickly. And, as has so often occurred in American history, an ingenious solution emerged from an unlikely place. In this case, an engineer with no PhD behind his name or experience designing reactors, cre- ated a solution so far outside the box that some doubted it would ever work. The ATR creation story is well known in INL circles, and thoroughly documented in Susan M. Stacy's book, "Proving the Principle, a history of the Idaho National Engineering and Environmental Laboratory 1949-1999." Deslonde deBoisblanc was a research physicist who had moved to Idaho from Oklahoma after the Atomic Energy Commission chose his company, Phillips Petroleum, to run the MTR reactor. Nine years later, on a lonely stretch of Highway 20, deBoisblanc came up with the famous ATR cloverleaf design that modernized the Nuclear Navy and allowed for the evolution of nuclear energy into a power source that provides 19 percent of the nation's electricity and 63 percent of its carbon-free electricity. In "Proving the Principle," deBoisblanc explained how his epiphany came to be: "As was the custom, I was driving Bryon Leonard, our consultant from Internuclear Company, to his hotel in Idaho Falls. It was one of those lingering twilight evenings, still quite light. On that straight stretch of Highway 20 across the desert, with its sage brush and the frequent lava flow patches, there wasn't much to distract us." deBoisblanc then explained to Stacy how he described to Leonard an idea for maxi- mizing the number of neutrons absorbed into the Navy's samples: "I reached over across the front seat of the car and with my finger drew four circles for test loops, and then a snake-like fuel line partially around each loop. Immediately, I saw that we could place another loop at the very center because the four arcs that surrounded the center loop were almost as effective as a circle. It soon became obvi- ous that by placing a beryllium reflector properly we could gain four more attractive loop locations. The more we looked at that strange arrangement, the better it looked." ATR's unique core allows its corner lobes to run at different power levels. This means multiple experiments can run simultaneous- ly under distinct pressure and conditions. DeBoisblanc and his remarkable creation are the ultimate argument against "We've always done it this way." So it is that, more than 50 years after he sketched the reactor design on that lonely stretch of highway, ATR remains the world's leading test reactor. "There would have been a reactor had The Advanced Test Reactor Complex with the Lost River Range in the background. PHOTOS COURTESY INL

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