A hard hat project sticker traded around the NTS

A hard hat project sticker traded around the NTS

Author: Solidus

Zero time is when nuclear testing truths come home to roost. In just a few shakes the physics, engineering, and construction life-cycle is completed. Either the experiments worked or they didn’t; the data was collected or it wasn’t; the engineering was adequate or not; and the construction contained the event or it didn’t. Zero time at the Nevada Test Site Area 12’s Rainier Mesa was generally the culmination of at least two years of hard work and there was never any going back to do it over. It was right the first time or it failed. Oh, in case you are wondering, a shake is unit of time equal to 10 nanoseconds or 10-8, which is the approximate time it takes for one step in the nuclear chain reaction or the shake of a lamb’s tale so I was told. It is all over in fifty to one hundred shakes.

Containment starts early in the nuclear testing world. As the instrumentation alcoves and drifts, a secondary tunnel passageway, were mined for Misty Echo, the geologists, geotechnical engineers and the physicists mapped and strengthened the areas of the tunnel they felt were weak. Rainier Mesa is comprised of volcanic tuff, which means it is composed of volcanic and mineral fragments in a volcanic ash matrix. Tuff forms when some combination of ash, rock and mineral fragments (pyroclastics or tephra) are blasted into the air, then fall to the ground as a mixed deposit. It seems that when the volcano blows it doesn’t always mix everything uniformly so here and there throughout the tunnel were weak areas of tuff interspersed with the strong areas. The mesa’s hard top is called a cap rock and, from the reports, is a tuffaceous sandstone. What all this means is the N-tunnel complex, with the magic of the geo-scientists and modern rock-matching grout, could handle the Misty Echo event and be expected to contain the nuclear bad actors.

Misty Echo was my first nuclear test. The mining in N-tunnel for the Misty Echo event was aleady complete when I showed up at NTS; a wet-behind-the-ears, electrical project engineer. I had been hired by Holmes & Narver, the DOE’s architect and engineering firm. When I was told my skills would be employed for the wiring of all of the instrumentation alcoves in addition to the test power, my knees about buckled. Why did I think there would be an apprentice period during which I learned these things from someone more experienced?

My office in Area 6 was shared with a disgruntled employee who complained nonstop. I was, of course, guntled and excited, just scared to death. With hard work, a policy of prolifically questioning everything, and many hours underground, I gradually settled into a routine. My course work was in power engineering and we take our amperes in whole numbers. Instrumentation was the work of the mysterious sneak amp people who take their amperes in tiny fractions, which terrified me. No one ever saw the terror or the relief I felt when I found out that the big boys from LLNL, LANL, Sandia and DoD took care of their own instruments. My responsibility was, simply, to get the correct voltage and amperage to the instrumentation alcove, prepare the Faraday cage for ground reference, and shock mount the various instruments.

Sometime during the Misty Echo preparations, mining was started for The Mineral Quarry event and I was promoted to Design Engineering manager. Don’t ask because I have no idea why I was chosen. The only thing of note I had accomplished was the design and implementation of a tunnel ground reference. My new responsibilities meant I had to be able to gain the respect of and manage structural, mechanical, civil and other electrical engineers, all of whom were super stars. I moved from Las Vegas to Mercury, Nevada to be closer to the action. When my office work day was over, I walked the mile underground in N-tunnel and took untold grief from craftsmen as I prepared as-builts of the Misty Echo construction. Every pipe, cable, penetration, and Vistanex box was verified and mapped or field changed as required. Vistanex, the base for chewing gum and many ‘rubber’ products, is a nasty, highly viscous substance. Boxes of Vistanex held thousands of cables as part of the containment strategy. Very high pressures, like those developed during detonation, force tiny gas bubbles of bad stuff up the cabling where they escape through tiny holes in the insulation. Vistanex contained the evil bubbles.

There are many aspects of a containment strategy, but one of the most dramatic is the Line of Sight or LOS pipe. In general, there is a 10-foot or so diameter steel pipe that leads from the physics package to the experiments and, because we were mostly simulating space, the LOS was under vacuum. Once the reaction was initiated and the experiments exposed, a large gate dropped into place, and the pipe was sealed pipe just outside of the cavity using shaped charges placed around it. The LOS is crimped and twisted like play dough in the hands of a child. If a mere mortal could watch the show, the timing of all of this activity would appear simultaneous. In nuclear time, however, it is a very long duration. Misty Echo had some twists and turns but the idea was the same. Toward the end of construction, I rented half a tiny trailer in Area 12 so I could get more than a couple of hours of sleep. I learned and I learned fast.

Construction complete, Misty Echo’s device was transported and placed. Gone were the good old days when the nuclear cowboys threw the physics package into the back of a pickup, picked up a few spare beryllium windows, and drove to the emplacement site. Misty Echo’s transport was a real production number during which most of us were confined to quarters.

Once the device was placed in its chamber, the tunnel was buttoned up. Button-up is actually a gigantic checklist in the hands of the DNA Commander. The button-up team backed out of the tunnel assuring that each step was complete, each exit was sealed, and the event was ready for final count down. Although DOE’s A&E was represented by the Area 6 manager, an exception was made for me to tag along like an indulged, happy puppy. I took everything very seriously and did step and fetch it for the team for the entire 14-hour ordeal. Upon completion, a muster was held and, except for direct support, all others left the area. The tunnel was then pressurized, the acid test, as part of the containment strategy. That a tunnel into a mesa of tuff can be pressurized at all is to the great credit of the geo-technical and construction teams.

Following muster, those of us staying on retired to the command center where we would wait for the President and others to give two thumbs up so the test could proceed. The wait time dragged and one of the generators on the mesa quit in the middle of the night. December on a high desert Nevada mesa is cold. But I was the junior team member so off I went with a colleague and a can of ether to restart it. Brrrr… I finally feel asleep on a couch. Rudely awakened, I was advised that the test director was waiting. For what? I wondered. I had been abandoned by the rest of my team sometime during my sleep and I was being called to testify that construction had been completed in accordance with the engineering construction drawings. Suddenly all the hours of my own time spent underground doing as-built drawings paid off. I was able to state that, indeed, the construction was completed in accordance with the drawings.

The countdown, initiated so many months ago, was complete. At zero-time the physics package detonated. Descriptors of my feelings from that moment remain elusive after all of these years. I can only say it was overwhelming. There was no sound. The mesa appeared to expand and lift, then settle back on its pediment. A puff of rock dust here and there was all that could be seen but in my mind I swear I saw the reaction go forward, one shake at a time. I saw the explosive charges seal the cavity, hopefully forever. Of all the intelligent questions I could have asked, my only query was whether or not they got the data. The day dawned, the event was contained, and the data was captured. Suddenly, all I wanted was sleep. Tomorrow, re-entry would begin.