_____                   _                  _____            _____       _ 
  |     |___ _____ ___ _ _| |_ ___ ___ ___   |  _  |___ ___   | __  |___ _| |
  |   --| . |     | . | | |  _| -_|  _|_ -|  |     |  _| -_|  | __ -| .'| . |
  |_____|___|_|_|_|  _|___|_| |___|_| |___|  |__|__|_| |___|  |_____|__,|___|
  a newsletter by |_| j. b. crawford               home archive subscribe rss

>>> 2022-09-15 the nevada national security site pt 3

part 1 | part 2 | you are here | part 4

I said up front that the NNSS remains in use for several different purposes, although the level of activity today is not nearly as high as it once was. To my best ability to remember the numbers, I think we were told that during the period of active testing the staff compliment was about 13,000. Today there are about 8,000 personnel that work at the site, between the various contractors and subcontractors. This is as good a time as any to elaborate a bit on the organizational structure of the NNSS.

One of the interesting things about the nuclear weapons complex is the extremely high level of at least semi-privatization. While the NNSA is either the largest or second largest component of the Department of Energy by budget (it depends a bit on exactly how you break down the DoE's various buckets of funding), it makes up well less than a quarter of the DoE staff. This enigma results from contracting: considered as the NNSA, the nuclear weapons complex is more than 50,000 people. Only about 2,500 are federal employees. The rest are employees of a dizzying network of contractors that range from well-known defense entities (Lockheed-Martin) to the small and surprising (San Ildefonso Services, a fully owned enterprise of the sovereign government of the Pueblo of San Ildefonso, comprising about 600 enrolled members and northwest of Santa Fe).

Very few people civilians involved in nuclear weapons are actually federal employees, and they're limited mostly to the NNSA offices that exist to coordinate and supervise these many contracts.

This staffing analysis admittedly excludes the sizable military component of the nuclear weapons program, as each military branch has an organization dedicated to the handling and deployment of nuclear weapons as well as the personnel in the field that are actually responsible for it. For historic reasons rooted in the genesis of the Manhattan Project, though, nuclear weapons are viewed as being more a civilian matter than a military one. Although the separation has decayed over decades, it has always been the gist of the situation that the Department of Energy owns nuclear weapons, and the military is allowed to borrow them. The military, of course, has its own extensive contracting operation, and many military organizations related to nuclear weapons are extensively staffed by contractor employees.

While privatization of defense functions is mostly a newer trend, it is deeply rooted in the world of nuclear weapons. Since the very beginning, the Manhattan Project relied heavily on the work of various outside organizations, first among them universities. A substantial portion of the Manhattan Project, including most of the operations at Los Alamos, were actually performed by the University of California. Los Alamos Scientific Laboratory and later Los Alamos National Laboratory continued to be managed as a subsidiary of UC until 2005 when both UC and DoE initiated a series of changes that saw LANL transferred first to Los Alamos National Security (LANS), and then just over a decade later again to Triad National Security. UC remains one third of Triad, along with the Battelle Institute (a nonprofit heavily involved in federal research and development) and Texas A&M.

Sandia National Laboratories, originally a division of LANL and thus UC, was transferred to Western Electric in 1949 and remained a concern of AT&T and Bell Laboratories until until 1993, when it was transferred to Lockheed-Martin. AT&T's involvement in nuclear weapons is not limited to telecom or even communications R&D; AT&T was in fact a major component of the weapons enterprise for decades. Today, Sandia is operated by Honeywell, as are several other components including the Kansas City National Security Campus.

The split between LANL, operated by universities, and Sandia, operated by engineering organizations, reflects the history and culture of the laboratories. While both conduct extensive basic research and there is plenty of overlap in functions, the broad division is that LANL is responsible for the design of the nuclear device itself (an issue at the cutting edge of physics) while Sandia is responsible for a way to deliver downrange (a matter of ballistics and mechanical engineering). Even the locations reflect this divide: LANL hidden high on a mesa, and Sandia in the desert scrub of a ballistics research range dating back to World War One and the New Mexico School of Mines' (my alma mater, under its present name of New Mexico Tech) work on proximity fuzes.

These early examples of full-service federal contracting were major precedents in the creation of the "GOCO" or Government Owned, Contractor Operated model. While nuclear weapons facilities are owned by the federal government, they are almost all operated by either a private company or a public institution (or perhaps a coalition of some combination of the two). The operator, often called an Operations and Maintenance or O&M contractor, is paid a "management fee" to perform this function. A related concept is that of the FFRDC or Federally Funded Research and Development Center, an umbrella category that was created to somewhat standardize the legal nature of nuclear weapons laboratories as well as several other government-owned R&D organizations such as the DoD's Aerospace Corporation and Rand Corporation.

While FFRDCs are not necessarily related to nuclear weapons (some having been born entirely in the military or department of commerce), a large portion of them and most of the larger FFRDCs fall under the auspices of some component of the Department of Energy. Most of the DoE FFRDCs, arguably all, are either historically or currently involved in nuclear weapons. Only three, Sandia, Los Alamos, and Lawrence Livermore are directly considered nuclear weapons laboratories (these are sometimes referred to as the tri-labs). Nuclear weapons as a broad state function have many aspects beyond the design and testing of weapons, though. Savannah River National Laboratory, for example, located at the site of a former uranium refinery in Tennessee, is primarily involved in researching environmental remediation and hazmat handling methods. Expressed as a quip, Savannah River National Laboratories exists to try to find a way to clean itself up.

This is all a long preamble to explain that there are a lot of distinct organizations involved in nuclear weapons and it can be difficult to keep track of them. Names like EG&G, SAIC, and UC ought to be as closely connected to nuclear war as the Manhattan Project.

In the case of the NNSS, the name to know is Mission Support and Test Services or MSTS LLC. MSTS is a coalition of Honeywell, Jacobs Engineering (builder of nuclear reactors), and Stoller Newport News Nuclear (builder of aircraft carriers). More subcontractors than can be easily listed perform various functions on the behalf of MSTS, including the amusingly named "Securing Our Country" which provides the private paramilitary security force at several nuclear weapons sites. Apparently embarassed at the somewhat cringy name, they now tend to insist that it's "SOC" and it doesn't stand for anything.

The NNSS staff today is made up of the employees of all of these contractors, and most of the staff are involved in maintenance and cleanup activities. This is a common theme in the world of nuclear weapons: managing the legacy of environmental contamination and hazardous waste is just as big of a job as, and sometimes bigger than, actually designing and building weapons. Even maintaining roads becomes a substantial operation at the scale of the NNSS.

Two major facilities at the NNSS speak to this point. The Radioactive Waste Management Facility, which was pointed out to us in the distance, receives low-level mixed waste from other DoE and DoD sites that needs to be removed and disposed of elsewhere (instead of being permanently disposed of on-site, which is typically the preferred option to avoid the political controversy around transporting nuclear waste). This type of waste is made up basically of the contents of trash cans in laboratories that handle nuclear materials. Gloves, aprons, instrumental apparatus, storage containers, etc that were exposed to nuclear material and thus remain slightly radioactive due mostly to particulate contamination. There are even building materials from demolition of contaminated labs, animal carcasses from medical testing, and low-level radiation sources removed from medical equipment.

This waste is inspected, packaged, and then buried in a series of shallow trenches engineered to prevent any leakage or wind dispersion. Ongoing monitoring will be performed, essentially into perpetuity, to ensure that the containment mechanisms are effective. The RWMF benefits greatly from its remote, arid location: it is far above the water table and far away from populated areas, granting a significant safety margin.

It also benefits from its location well inside of a secured federal reservation. The RWMF is able to accept classified waste, such as components of classified designs, for burial. This capability is uncommon enough that NNSS is the final resting place of some classified objects that are not radioactive or hazardous at all, simply impractical to destroy. I have previously mentioned on this blog that the NSA lists "permanent burial" as an acceptable method of destruction of classified matter. Here it is, out in the Nevada desert.

Elsewhere in the NNSS, some low-level waste has been buried inside of the subsidence craters resulting from underground tests. This method is convenient and permitted for certain types of lower risk waste, much of it brought in from the nearby Tonopah Test Range. As in most federal facilities, disposal of hazardous materials is restricted by state law, and so all of these waste handling activities are conducted under permits from the Nevada Division of Environmental Protection. The state and federal governments coordinate a variety of precautions and restrictions on the transportation and handling of waste, which include a prohibition of transportation of waste on certain busy freeways and highways and selection of routes based on weather conditions.

As part of its efforts to mitigate transportation risk, the NNSS grants substantial funding to nearby fire and emergency management departments to support their general operations and specifically radiological response capabilities.

This is not to say that NNSS activities today are all about cleanup. Another facility pointed out to us in passing, near the U1a complex, is the Device Assembly Facility. The DAF was constructed as a new consolidated building for the safe handling of nuclear weapons components, including both nuclear material and high explosives. It consists of a series of isolated underground cells, each designed for the safe containment of a huge explosion. These are accessed by a fortress-like concrete portal cut into the ground, flanked by guard towers and surrounded by multiple layers of fencing and intrusion detection. Because it can contain a substantial quantity of "special nuclear material" (in other words, weapons-grade plutonium and uranium), the DAF is likely the most security-sensitive facility on the site and is guarded 24/7 by a paramilitary force and numerous technical security measures.

The disconnect between public perception of security at defense facilities and the actual reality can be stupifyingly large. Media depictions give many the idea that a typical military installation is defended by laser perimeters, dog patrols, and a heavily armed response force. Of course, most military installations are actually protected by nineteen-year-old enlistees running more on Red Bull than tactical training, and response to even the most obvious security violations is more likely to take 30 minutes than 30 seconds.

The weapons complex tends to run on the more secure end of government operations, but as a group of nuns memorably demonstrated even some of the most sensitive nuclear sites are vulnerable to wirecutters and determination. The NNSS, like many military and weapons installations, both benefits and suffers from its immense size. Hard perimeter security of over 1,000 square miles simply isn't practical, and a daring person could probably walk right into the NNSS and remain unnoticed for quite some time. There may not even be a fence for much of the perimeter. Harder protective measures are found at individual security-sensitive sites. On the upside, the many miles of barren desert between actual facilities and the perimeter make it very difficult to escape undetected after triggering any sort of alarm.

Still, the DoE faces the same budget pressure as the military, and security measures have certainly decreased since the days of the Manhattan project. Los Alamos personnel in the 1940s were trained on a "badge challenge" procedure: when a guard trained a gun on them, they would set their ID on the ground, turn the other direction, and walk ten paces to wait until instructed otherwise. Although I hear this has changed in recent years, when I was in Los Alamos they were indecisive on whether or not it was worthwhile (or perhaps more truthfully, within their budget) to check badges in person at all. Throughout the weapons complex there are many visible remnants of security measures that once were, replaced by dwindling patrol forces that, admittedly, remain very well-trained---particularly by the lax standards of US law enforcement.

This came to my mind contemplating the guard towers of the DAF, some of the only guard towers that can be found anywhere in a nuclear weapons installation. In my career I have worked in one environment that I would call extremely secure. It was not a weapons or military installation. It was a Federal Reserve Bank. In employee orientation, a sergeant of the Federal Reserve Police told us proudly that there has never been a successful heist on the Fed, although it's been depicted fictionally several times in films. 82-year-old Megan Rice got to the Y-12 enriched uranium storage complex to commit principled vandalism... by her description and the admission of Y-12 security forces, basically by walking right in.

After the end of testing, with device assembly no longer a major activity, the DAF was converted to the National Criticality Experiments Research Center operated by LANL. Here, researchers directly handle complete nuclear weapon pits and other quantities and forms of special nuclear material that are capable of prompt criticality. The DAF serves not only to protect these materials from theft but, perhaps more importantly, to protect the outside world from the effects of a criticality accident.

On the matter of response times, as we drove through the complex we passed by another fire station. Our guide explained that the NNSS fire department had a target of a 30-minute fire or medical response to any part of the range that was in use. While the two stations put most of the NNSS within 30 minutes, when the Pahute Mesa, in the far northwest of the NNSS, is in use it's necessary to stage an ambulance and fire engine at the "midway" point between the second station and the mesa, about 30 minutes from each. Despite the seeming danger of the NNSS, most of the fire department's time, he said, was spent on mutual aid to the rural departments around the area. There are a lot of one-ambulance towns in Nye County, and the NNSS's EMTs regularly meet up with those ambulances to take their patients into Las Vegas, allowing the rural ambulances to return to duty a couple hours sooner.

As with most nuclear installations, the NNSS has an on-site medical clinic which is both equipped to handle radiological emergencies and a great convenience to the staff. NNSS is one of the DoE sites which enthusiastically holds a "VPP Star," a distinction awarded by OSHA for effective implementation of a Voluntary Protection Program. VPPs are occupational safety programs that go beyond the legal requirements, and to hold a VPP Star an employer must maintain below-average injury and illness rates. Some nuclear sites such as LANL have developed something of a reputation for a troubled safety culture, but others excel in implementing their safety programs. Surprisingly, working with nuclear weapons can be one of the safest career options many craftspeople can take.

Leaving the underground testing area, our coach briefly descended into the subsidence crater left from an underground test, the driver somewhat nervously navigating the steep road rutted by recent rainstorms. The odd thing about underground testing is just how underwhelming ground zero is. While the crater was about as deep as our coach was tall, perhaps 12-15 feet, it was only about a thousand feet across, and the bottom much smaller. At the center, a wide, rusted metal column jutted out of the ground at an odd angle, cut-off cables hanging out the top and birds nesting in an aperture in the side. This was the top of the casing of the shaft, and the only direct indication of the actual nuclear device.

Parked for a moment at the bottom of the crater, I contemplated how we were ourselves displaced downwards as a latent effect of a nuclear explosion. We tend to imagine the result of nuclear weapons in terms of Hiroshima and Nagasaki, but in the world of industrialized testing that same power is neatly managed and contained. Even the radiation effects are quite minimal. Near the center of the crater was a ring of fencing with radiation hazard signs. Our guide explained that the radiation in the crater had never measured significantly higher than background, but as part of a groundwater monitoring project a water well had been drilled from the crater down to near the detonation point. Years ago, water had been pumped from the well into a tank and then sampled to monitor contamination. Some of the water had leaked from the fittings, and so even though no radiation had been found, as a matter of policy the area where the water pooled was considered a danger and required radiological protection for entry.

Much of the safety and security of these sites comes from this type of pedantic compliance with broad precautions. I am reminded of the story of the top secret orange. The story goes that a laboratory at Los Alamos which handled metal models of weapon pits (which were of a classified design) found that the guards sometimes weren't sure whether or not a given object was a model pit and thus classified. To resolve the issue, they adopted a policy that all spherical objects within the lab must be kept in safes when not attended. Perhaps you can guess the punchline: a laboratory worker was written up for a security violation after leaving an orange on his desk. Sometimes strong systematic security requires treating fruit as presumptively classified [1].

On the way around the crater our guide mentioned that you could see a USPS truck at the rim of the crater. Not as the result of any experiment on the nuclear survivability of letter carriers, but just because it was a government surplus item that made a convenient enclosure for some monitoring equipment. Unfortunately it had disappeared: "it was just there two weeks ago!" our guide insisted. Like beige paint and breezeblocks, odd bits of government property that disappear as quickly (and mysteriously) as they appeared are part of the aesthetic landscape of the nuclear weapons complex.

A limited budget, an oddly strong sense of thrift, and a close relationship to the military result in extensive use of the cast-offs of other federal agencies. Federal spending is always a bit of an enigma this way. For every billion dollars spent on F-35s there are at least fifty enlisted personnel emptying trash cans under roof leaks. The DOD plunges into a multi-year, multi-billion boondoggle to replace HEMTTs while National Science Foundation grantees repurpose retired units to move their building supplies.

A remarkable example of this phenomenon is our tour's next stop.

One of the better-known historical sites at the NNSS is the "gun turret." It is not a gun at all, although it once held one. Collecting data from nuclear tests has always been a challenge, and even for atmospheric tests it was difficult to place instruments close enough to ground zero to collect data without taking damage from the shockwave. Somehow, the details of which seem lost to history, someone at the NNSS implemented a clever solution: a turret, borrowed from a scrapped Navy cruiser, was stripped of its three 8" guns and shipped to the Nevada desert.

A somewhat improvised gun emplacement was built on a mesa at the NNSS and the turret installed in it. In place of the guns, a single "barrel" made of lead wrapped in sheet metal was installed on the front. For a series of several atmospheric tests, measurement instruments were placed in the barrel and the turret was aimed squarely at ground zero. Because the lead barrel blocked both light and background radiation coming from off-axis sources, this allowed for accurate measurements of light, x-ray, and gamma output that were used in verifying performance calculations. Since the turret could be re-aimed at various test positions and was cabled to permanent underground recording equipment bunkers nearby, it allowed for a lot of saved money compared to the conventional approach of trenching long cables from recording bunkers to instruments near the device that would not survive the explosion.

As I mentioned, the history of the gun turret was not well documented. Fortunately, as our guide tells us, an NNSS employee spent some spare time carefully examining it and was eventually able to find a serial number on an original component. Research aided by a naval museum determined the origin to be the USS Louisville, which during World War II suffered strikes by Kamikaze pilots twice. The Louisville was repaired and returned to service both times, and participated in end-of-war activities including the evacuation of prisoners of war before being sold. The turret in question was damaged in one of the Kamikaze strikes and swapped for a spare. By the time repairs were completed the war had ended---and so it sat as surplus in a Navy yard for a decade before being picked up for use at the NNSS. Due to the enormous size and weight of the turret, its delivery to the NNSS was itself a complicated operation. It was shipped over sea by the Navy to Port Hueneme, and then trucked nearly 400 miles over land by a heavy hauling contractor.

There is an obvious symbolism to the gun turret's new home in the desert. Like the USS Desert Ship, a pseudo-vessel apparently run badly aground in White Sands Missile Range for testing of missile systems, the gun turret is a curiosity: a ship out of water. It is also a weapon repurposed for science... but for the science of developing better weapons. Swords may be beaten to plowshares but plowshares are not always entirely innocent. Plowshares will return, in a dramatic fashion.

At least as far as I can keep my timeline straight, the Gun Turret was our last stop before lunch, and that's a good time for a break. Keep an eye out for Part 4.

part 1 | part 2 | you are here | part 4

[1] I write this story the way I do because I am honestly not sure if it is true. I believe I originally heard it at LANL where it was told in the way of an urban legend, but it has also occasionally appeared in reputable sources. Anyone who has been through LANL's employee safety training, and has experienced the instructional video on the requirement to use handrails when climbing stairs, probably finds it credible.


>>> 2022-09-13 the nevada national security site pt 2

part 1 | you are here | part 3 | part 4

After our time milling around the Mercury cafeteria, it was back aboard the coach to enter the test site proper. As our guide explained, the NNSS can be divided into work areas such as Mercury and the range itself. On the days that tests were scheduled, everyone other than personnel for that specific test was prohibited from entering the range area for safety reasons. Considering weather delays and technical issues, this sometimes meant a full day of lost work as the entire staff huddled in Mercury awaiting news that they could once again head out to test sites.

The first point on the tour after Mercury, then, and perhaps the first truly related to nuclear testing, was Checkpoint Pass. Here, where the road passes over a low ridge, there is still a wide part of the road with a row of floodlights where guards would check if each person was on the staff list for the test of the day. This is one of many places where the history of nuclear testing seems remarkably well preserved, even ready to be returned to use. There are reasons for this, as we will discuss later.

Shortly after Checkpoint Pass our guide points towards Control Point. This is the building from which underground tests were actually performed. Like the operations control center, it is a largely unremarkable low concrete building. What stands out is the rack of microwave antennas spanning the side of the building facing the valley. Presumably a great deal of microwave communications were used for control and monitoring, probably in the later era of testing based on the use of delay-lens antennas. Microwave communications were widely deployed by telcos in the 1950s but the equipment and antennas were exceptionally large and heavy. I am not sure if this early microwave equipment would have been used in the frequently-reconfigured testing environment. By the '80s microwave would have become an inexpensive and fast to deploy network medium.

The microwave infrastructure here was clearly substantial. Looking down the ridge into the valley several passive repeaters (billboard-like structures that act as mirrors for directional microwave links) can be seen, their aim suggesting that they allowed antennas at Control Point to reach sites on the other side of a hill to the building's west. Passive microwave repeaters have always been a minor fascination of mine. They are only really practical for the very short wavelengths of GHz microwave systems, and the high attenuation of a passive reflector combined with the ever lower cost and maintenance burden of active repeaters makes them rare today. Passive repeaters can sometimes still be found in use by rural telcos to reach AT&T or MCI sites outside of direct view of their exchange facilities, but perhaps the best places to hunt for them are dams. Likely a majority of the hydroelectric dams of the southwest, often being in deep canyons, used passive repeaters set on the canyon rim to get telephone and industrial control signals to the powerhouse.

I should avoid dallying too long on the details of the telecom equipment, but this will not be the only example I find interesting. The communications infrastructure at these types of national security sites is a revealing example of the very close relationship between national defense and the telecommunications industry---especially AT&T, which at the NNSS as in other places is practically an arm of the government.

Just past control point, our guide calls out two sets of wooden benches, one at each side of the road. These were the spectator stands for atmospheric tests, set far enough away for safety but with a clear view. Anyone not wearing safety goggles was required to face away for one minute around detonation, protecting them from vision damage due to the intensely bright light. One set of benches, closer to the road, was for government officials and other VIPs. The other, somewhat further away, was for the scientists and engineers who had planned the test. And just a bit ahead of the benches, a rocky outcropping is known as News Nob due to its use by media crews invited to report on nuclear tests.

Despite the commonplace nature of worn wooden benches and a rock face, this is one of the more emotionally impactful sites on the tour. From 1951 to 1963, the NNSS detonated nuclear devices above ground, typically on short metal towers. These tests were not just sources of data but spectator events. On this topic, our tour guide, who had seen underground tests but started decades too late to see any above ground, seemed practically wistful. "Imagine what it would be like to see that," he said. I cannot be sure if this is reality or an embellishment by my own memory, but I could swear that he then echoed the words of Oppenheimer and the Bhagavad Gita: "to see the radiance."

This is one of those things about nuclear weapons that is difficult to capture in language without resorting to poetry. As much as we might hope for disarmament, and as much as we might celebrate the end of atmospheric testing and the end of all testing some decades later, I am quite sure that we all want to see it, just once. Lot's wife, as we usually understand it, turned back to see the cities. I have always thought, though, that it is a better explanation that she turned back to see the destruction. Who wouldn't be curious about the physical manifestation of God's power? A surprising number of people, sitting on those benches and equipped with protective eyewear, saw just that. They looked down on Frenchman Flat, toward all the land of the plain, and saw dense smoke rising from the land, like smoke from a furnace (Gen. 19:28 NIV). Lucky that Oppenheimer had developed a fascination with Hinduism; had he been a Christian, he, too, might have been turned to salt. Then again, he might not have been labeled a Communist and stripped of his clearance. Oppenheimer had a difficult time with more than one higher power.

As our coach carried on towards Sodom and Gomorrah, the guide pointed out the two matching sets of utility poles, one on each side of the road. During testing, utility crews would relocated the electrical lines to whichever side of the road was opposite the current test site. This way, cranes and other tall vehicles could be moved more easily and safely. Likely from later testing, there is also a tremendous amount of buried conduit throughout the valley. At seemingly random locations, but probably corresponding to various tests, rusting electrical panels popped up by the side of the road with disconnects and pin-sleeve connectors. Small signs marked the route of high voltage raceways, and numbers on the panels hinted at a probably rather hairy stack of maps and diagrams.

For quite some distance along this road a hefty bundle of telephone cables runs along its own poles. One branch of it heads uphill to a microwave site atop a small peak, south of control point. It continues some way into the valley but likely drops into underground conduit before too far.

I wondered, of course, who installed and maintained the telephone infrastructure. While I cannot provide an in-depth discussion of this topic (at least not yet), the existence of an AT&T special toll area tariff for the Nevada Test Site suggests that AT&T provides the service, and the tariff includes detailed rates for certain services which were or are presumably in use. This includes a Dimension 2000 PBX (nearly $10,000 per month after a $75,000 installation charge), a 225 kW diesel generator, and dedicated emergency lines. The Dimension 2000 is capable of up to 2000 lines and 14 attendant consoles. This equipment was probably installed somewhere in Mercury in an NNSS-provided building, and maintained by appropriately cleared AT&T personnel.

The microwave site near Checkpoint Pass has been licensed, at various recent times, to WCS Microwave Services and Verizon Select Services. Neither company is easy to find much information about, but both seem to bid on various government contracts for connectivity. WCS is a subsidiary of Williams Communications and VSS is, of course, a subsidiary of Verizon Communications. I would hazard to speculate that the NNSS turned to these vendors to provide their backhaul (and based on license locations some internal connectivity) after the breakup of AT&T introduced a great deal more competition in that market. It's interesting that Williams Communications specializes in cable television systems, inviting one to wonder if they specifically provided services related to the many video cameras that were used to observe and record tests.

As we drove further into the valley, several towers started to loom on the horizon. One of them was our next destination: the Icecap site. Icecap was an underground nuclear test planned to be 20-150 KT and buried 1,550 feet underground. It was scheduled for Spring 1993, just months after the official issuance of a moratorium on all nuclear testing. As a result the site, nearly ready for the test, was abandoned in place. It now serves as an excellent historical example of the preparations for an underground test.

There are several prominent features at the site, but at the core is a 157 foot tall modular metal tower. After drilling of the test shaft was completed (at 3-5 feet across with very tight linearity tolerances this was no small feat), a metal cover was installed over the shaft for safety and a set of sea container-like modules stacked above it to form a temporary tower. Inside of that tower, the tall cylindrical "canister" or "rack" was assembled. The canister is suspended from the top of the tower by cables. Round walkways throughout the height of the tower, reached by stairs and a small lift on the side, provided technicians with relatively easy access to different points throughout the canister.

The size and mass (300,000 pounds) of the canister are surprising, while the fact that large portions of it seem to have been sealed up with duct tape is a reassuring bit of normalcy. Nuclear testing is just about as complicated as the design of the weapons themselves. While the canister contained the "nuclear device" (not called a weapon because it is not equipped with delivery or fuzing equipment), most of it is taken up by a dizzying number of instruments that measure physical force, radiation, and other properties of the detonation. These measurements are the actual outcome of the test, and can be compared against calculations to determine the performance of the device.

There is a problem: nuclear detonations are a hostile environment for precision instruments. This is the central challenge of underground testing. In atmospheric testing, instruments can be located far enough away from ground zero to survive the detonation (we will see an example of this later). For underground tests, the radius of destruction is relatively small, but it contains far too much soil and rock for remote instruments to be useful. Instead, most of the measurements must be taken from the same shaft as the device.

To resolve this conundrum, engineers had to dance very closely with the destruction. It is simply the nature of underground nuclear testing that the measurement instruments will be destroyed almost instantly. They must collect their data and report it before the blast reaches them. Every underground test was a remarkable race: as the blast propagated through the canister, each instrument produced a signal which traveled through cables to safety just ahead of the advancing shockwave. Cables were turned to vapor just behind the messages they carried.

The canister, then, looks something like a diving bell. From the top, dozens of coaxial cables and just a few fiber optic bundles ('92 was still an early era for small-scale fiber optic systems) hang back down the tower and then out a small hatch at ground level, where they are lined up on a series of zigzagging wheeled racks that allow them to be unfolded as the canister is lowered.

The primary motivation for underground testing is containment of contamination. In a properly performed underground test, almost no radioactive particles escape to the surface. This is achieved simply through the tremendous mass of a thousand feet of earth. There is a problem, though: the shaft itself.

Once preparation of the canister is completed, the tower is disassembled and the canister is transferred to a crane. Due to the limited length of the crane's hoist cables, the canister is lowered into the shaft in a series of steps. After each step, it is transferred to hang off of anchors around the shaft while long rods are added on so that the crane can retract its cables, attach to the top of the rods, and then lower the canister another step. Once this slow descent is completed, the shaft is backfilled with materials carefully chosen to prevent the blast pushing them out. A certain amount of the backfill and suspension rods will be vaporized in the detonation, as will the cables.

The greater challenge is small leaks: because the cables have multiple layers of jacketing that are easily destroyed, they can provide narrow paths to the surface through which the immense pressure in the blast cavity will force fallout. To prevent this, the cables are periodically interrupted by "packings" where various mineral and artificial materials are sealed around the cable. These materials are designed to flow and fuse under heat and pressure, sealing off the cable path.

About ten meters from the top of the shaft, our guide points out a metal pipe sticking out of the ground. This is the casing of a second shaft, drilled to comply with mutual verification provisions in treaties with Russia. The Russian government has the option of installing their own instruments in this small second shaft, if they so choose, allowing them to independently measure the yield of the device. Our guide explains that this was rarely done in the late years of testing, as remote sensing and seismic methods had improved to the degree that Russia could collect the same information without the need to arrange a site visit. Nonetheless, the option was always made available.

A surprisingly short distance away from ground zero are the trailers. These are the endpoint of the cable's suicide mission, and contain a variety of recorders and control equipment that are used to both prepare the canister for the test and collect the resulting data. Even at their close range (around 200 meters) they are safe from any immediate effects of the blast, but within the blink of an eye after detonation the ground under them will be lifted slightly upwards before falling back down. At their position this movement is small but still extremely fast, creating enough G-force to damage equipment. To protect the recorders (some of which were likely still electromechanical even in these late tests), the trailers were installed on frames that sat on piers supported by stacks of honeycomb-like blocks of corrugated aluminum. These collapsed under the force of the shockwave and cushioned the trailers.

There are not just a few trailers. Some have been removed from the Icecap site but there are still almost 20 left, each one numbered to keep track of them as they were moved from test to test. Some are just enclosures for racks of equipment, others are frames with electrical switchgear and communications equipment. One wonders if any of the engineers who designed these trailers went on to contribute to today's modular data center systems. Sandia's involvement in mobile data terminals and control systems for the military suggests so.

As we drove away from the Icecap site (and passed a couple of other towers remaining from planned tests that were canceled at earlier stages of development), our guide explained the problem of the craters.

The whole underground testing area of the NNSS is littered with small craters, often packed in a surprisingly tight grid. These craters are not the result of soil thrown away by the detonation, which occurred far below them. Rather, they are subsidence craters. The heat of the detonation compacted, melted, and fused the materials near the device, leaving an underground cavern lined with a glass-like material. At some point after the detonation, the walls of this cavern would fail, causing a column of soil above the cavity to fall downwards. The resulting crater is not very big or deep and the test planners became adept at predicting the size of the craters, allowing them to place the trailers just outside. What proved far more difficult was predicting when this collapse would occur.

As we drove onwards, our tour guide took advantage of the coach's entertainment system and played a short film which he called "zero time to collapse." This video consisted of footage of a series of different tests, cut together so quickly that the effect was somewhat dizzying. Over and over, we saw footage from a helicopter circling a bit of desert as a voice counts down. At "zero" a chirping alarm sounds as a shockwave whips through the scrub---curiously, the wrong direction. Our guide explained this perceptual oddity: the lifting of the surface by the shockwave occurs too quickly to be caught on video or even really to be perceived by the eye. What you see instead is the soil falling back down to its original position with the acceleration of gravity, which of course settles to a stop first further away from ground zero where it was displaced by less.

Then, there is a cut, which skips over a period of minutes to hours (in some cases, we were told, as long as 48 hours). A voice, working off of seismic instruments that monitor for the failure of the cavern walls, says "collapse imminent" and within seconds the ground simply falls away, leaving a crater.

And then it repeats. Over, and over, and over, showing perhaps 20 tests. By the end it almost becomes boring, a highly accelerated introduction to the mundanity of evil. Not even the wonder of tens of kilotons equivalent creating an impossible cavern endures the about 900 underground detonations performed at NNSS.

Some of the tests are slightly different from others. In one, the video of the collapse is from a low angle and not very clear. Our guide explains that the helicopter had had to land for fuel while waiting for the collapse and so missed filming it. In another, the collapse is less a crater than a sinkhole, with neatly vertical walls. Our guide says that this result is an oddity and something of a mystery; it only happened in one test and presumably results from some detail of the geology that still hasn't been determined. In just one test, the voice counting down is a woman's, reminding you of the gender disparity that remains to this day in the defense industry. The nuclear weapons complex has its own deep history of sexism, homophobia, hysterical anti-communism, etc., but that is a topic for another time.

We are by this point many miles deep in the NNSS and have more miles to cover to reach our next stop. On the way, our guide points out some support facilities. The Big Explosives Experimental Facility or BEEF is a range equipped to test huge quantities of high explosives. As a whimsical anecdote, our guide explains that BEEF's cow-shaped steel sign had been stolen some time earlier, perhaps as a prank by military personnel. NNSS craft workers made a new, larger sign and then buried its base under a ton of gravel. That ought to discourage any future larceny.

Driving along the main road, we passed the U1a complex, or as our guide allows himself to joke once, the "A-hole." This deep shaft complete with mine-type hoist headworks, along with a neighbor, connects to a complex of underground tunnels where subcritical experiments are conducted. In these tests, weapon pits a little shy of heavy enough to achieve criticality are subjected to the high-explosive implosion mechanism used inside weapons. After the test the deformed pit can be measured to calculate the implosion forces. An addition to the U1a complex currently underway is a linear accelerator that will be used to image the internal density of the pits, giving more data about the accuracy of the implosion. In a moment my husband found especially amusing, our guide said that office space in the underground complex has become very limited but, due to the time involved in taking the hoist up and down, the scientists were reticent to regularly come to the surface. The office trailers at the top of the shafts are being renovated in an effort to lure the staff above ground and free up space. "The scientists have dug in," my husband quips, "and are refusing to come up. They say they want more plutonium."

This, too far into the series to explicitly touch on this important topic, is a good time to finally say something about stockpile stewardship. This is the greatest challenge of the nuclear weapons complex today and, by budget, the main activity of the Department of Energy.

The United States has not detonated a nuclear weapon in thirty years.

This raises a troubling question: do they still work?

Every year, the National Nuclear Security Administration (the component of the Department of Energy that oversees the weapons program) and directors of the three nuclear weapons laboratories (Los Alamos, Lawrence Livermore, and Sandia) prepare a report to the President of the United States. This report says that the Department of Energy is confident that the United States' nuclear arsenal is not only safe, but also functional. Some years ago I heard Dr. Jill Hruby, at the time the director of Sandia National Laboratories and now the Undersecretary of Energy over the NNSA, say that she considers developing the confidence to sign this report to be the most important function of the weapons program.

Because the only designs that have been subject to "real" quality control testing (by detonation of sample units) are more than 30 years old and thus have undergone radioactive decay, mechanical wear, maintenance and refurbishment activities, etc., and an increasing portion of the stockpile consists of designs that have never been tested, this assurance must make the directors a bit nervous. Our confidence in the nuclear stockpile today rests on subcritical testing, testing of individual components, and increasingly, computational modeling. It is exactly because of the challenge of stockpile assurance that a surprising portion of the world's most powerful computers are owned and operated by the Department of Energy.

A tremendous amount of effort has been put just into understanding how weapons-grade plutonium and uranium change (or don't) when left in storage for decades, and how to refurbish weapon pits. The same problems exist for the high explosives, neutron generators used to force prompt criticality, specialized thermal batteries that power electrical systems in nuclear weapons, and even simple mechanical components.

An enormous staff of people (probably 30,000 across the complex) and billions of dollars in budget go, essentially, to doing everything anyone can think of other than actual testing to determine whether or not nuclear weapons even work. Every year the degree of separation between tested designs and the current stockpile increases, and so this confidence becomes based on greater levels of abstraction. In a way, it adds a fascinating new aspect to the fear of nuclear apocalypse: the outcome of a nuclear war has perhaps become even harder to predict as the possibility increases that some portion of our nuclear arsenal (and, for the same reasons, that of other major nuclear powers) will just not work.

It is because of nervousness about this possibility that there have been some calls to resume nuclear testing in the United States. I will not go into analysis of this decision, although I personally am strongly opposed. It is a closer possibility, though, than you might imagine. At several points our tour guide gave the context that the NNSS remains under standing orders to be ready to pick up where it left off. While testing has not been performed for so long that mastery of all the steps involved is now somewhat questionable, the NNSS retains an inventory of ready-to-go boreholes, drilling equipment, tower modules and components. In theory, should the order come, the NNSS could perform an underground nuclear test within 24 to 36 months.

Subjectively, the NNSS does not feel abandoned so much as it feels like it is in waiting. And administratively, it is.

We are, at this point, probably only a few hours into the 8 or so hours of the tour. I will return with Part 3, once again probably quite soon.

part 1 | you are here | part 3 | part 4


>>> 2022-09-11 the nevada national security site pt 1

you are here | part 2 | part 3 | part 4

I promised a travelogue, and here we go. I'm not exactly a travel writer, but I was recently able to visit a place that's fairly difficult to get to, so I think it's worth sharing my observations. I started writing this because I thought there should be more on the internet about the NNSS tour program and the site and tour as a subjective experience. Personally I absolutely love tours, not just to see things but because I think the tour guide and the design of the tour are often just as interesting as the site itself. When you take a guided tour you are sort of seeing a place through the eyes of its own public affairs department, and when it comes to the national security state that is an especially interesting thing to behold.

So this is, in part, a dry recounting of the NNSS tour and how it works. It is also, probably in larger part, my thoughts and observations on the historical and modern cultural role of the NNSS. As the location of the vast majority of US nuclear detonations, it is perhaps the most profound artifact of nuclear weapons. At the same time, it is seldom seen and, well, there's not that much in it to see.

The Trinity Site, with its twice-yearly open houses, is something of a mecca for everything from anti-war activists to the most hawkish cold-war enthusiasts. On repeated trips to the Trinity Site I have seen brash Texans and Buddhist monks, both in awe, but both in very different ways. The Trinity Site seems to encourage visitors to engage at a more philosophical level, perhaps due to the widespread knowledge of Oppenheimer's quotation of the Bhagavad Gita, perhaps simply because there is honestly not very much to see there. You visit the Trinity site, at least if you know what it's like, to find out what it feels like to stand in the shadow of the "radiance of a thousand suns." There is no tour to speak of.

The NNSS, though, despite having a public tour program, receives far less attention. There is, you will find, a lot more to look at there. As a result, the NNSS visitor experience feels less emotional and more technical. At the same time, every feature the guide points out is imbued with that same radiance. The Trinity site is where a force of incredible destruction was first unleashed. The NNSS is where that same force was industrialized, refined, and made routine.

One of the first things you learn about the national security state is its penchant for renaming things. This is prominently true in the military, but you also see it in the Department of Energy. And so, the Nevada Test Site, having once been the Nevada Proving Grounds, is now the Nevada National Security Site. The verbosity of "National Security Site" is awkward but well in line with the "Kansas City National Security Campus" and "Y-12 National Security Complex," down to being frustratingly inconsistent.

That's all a preamble to explain that I will be referring to it as the NNSS, although during the time period I will mostly be covering it was not known by that name.

I don't intend to write a proper history here, but not that many people are familiar with the NNSS (at least by name), so I will give the general background. The NNSS was established in 1951 in response to the need for a long-term proving ground for nuclear weapons. In the days of the Manhattan Project proper, testing had been rather scattered: the Trinity test, the first and most famous test of a nuclear device, was conducted in a barren part of central New Mexico, near the north end of the White Sands Missile Range and often described as near Socorro although a better (but much smaller) town to relate it to is San Antonio.

To many viewers this might seem like an ideal test site, considering the enormous size of the White Sands military reservation. That itself was a problem, though, as the Army made quite a bit of use of White Sands to the extent that the Trinity test camp was accidentally hit by pilots practicing bombing runs---not once, but twice. Moreover, fallout from the test reached the Chupadera Mesa where it injured cattle and potentially ranchers. The extent of the radiological contamination of the Chupadera Mesa is the subject of ongoing controversy today.

For these reasons, subsequent nuclear testing was mostly performed in the Pacific Ocean. In 1946, two weapons were detonated at Bikini Atoll in the Marshall Islands. These tests badly contaminated Bikini Atoll and the region, as well as Hunter's Point Navy Shipyard in San Francisco and potentially other sites at which Navy support vessels were decontaminated post-test. In 1948, three additional tests were conducted at the nearby Enewetak Atoll; contaminated topsoil from the atoll was interred under a concrete dome on Runit Island which is now in danger of failure due to tidal incursion. According to Los Alamos's curious tradition of naming things after places it destroyed, Bikini Atoll and Enewetak Atoll are both streets in LANL's main office complex, TA-3.

These Marshall Islands tests were followed by a brief reprieve, lasting until 1951. A curious thing about the Manhattan project is how quickly it ended: after the conclusion of World War II, there was a brief period in which nuclear weapons didn't seem especially important. The weapons program almost shut down during this period, and there was no effort towards stockpiling. It briefly seemed like the whole thing might have been a bit of a one-off, not a major ongoing function of a nuclear state. It did not last.

In my eyes, 1951 marked the beginning of a real, organized nuclear testing program in the US. Prior to that had been scattershot experiments coordinated somewhat haphazardly. From 1951 onward, nuclear testing was operated as an ongoing business function, using an established process and permanent infrastructure. While testing would continue at the Marshall Islands for about a decade further, mostly to accommodate larger-yield tests, the cost of performing them so far overseas was tremendous. For the testing program to be cost-effective it needed to be domestic. Ongoing domestic testing required an area even more remote than southeastern Socorro County: southeastern Nye county, Nevada.

Over 1,000 nuclear detonations occurred within the ~1300 square miles of the NNSS. While the vast majority were underground, 100 were conducted above ground. The mushroom clouds were visible from the Las Vegas Strip. Fallout from these above-ground tests headed mostly away from civilization until Utah, where it almost certainly resulted in excess fatalities due to cancer. The underground tests left little evidence other than a vast valley of small craters, each the result of soil falling in on the glass-lined underground cavern created in milliseconds by the buried weapon.

The NNSS is still in use today, although nuclear testing ended in 1992 following to the Comprehensive Test Ban Treaty. Perhaps the most dramatic activity today is subcritical testing, in which the pits and high-explosive components of nuclear weapons are tested under real detonation conditions---but with too little radioactive material to achieve criticality. Because of the involvement of both nuclear material and a lot of explosives the process must be treated much like an actual nuclear test. The site is also used for long-term disposal of low-level nuclear waste from the weapons program, counter-terrorism testing and training, and the National Criticality Experiments Research Center, one of only a few sites capable of conducting experiments with quantities of nuclear material that could become critical.

It is an odd happenstance that the NNSS is both exceptionally remote and only about an hour from Las Vegas. This makes it something of a tourist destination. In the days of atmospheric testing (the '50s to early '60s), tourists used to visit Las Vegas during announced tests in hope of seeing the flash and cloud. Today, it is possible to take a tour, although not especially easy. Public tours are held nominally once a month and have a capacity of about 20 people. They're usually full up well in advance. Some years ago I had set up a script that would check the webpage on tours for changes and notify me, so that I could apply for a tour as soon as the next batch of dates were announced (usually about six months at a time). I succeeded in reserving space for myself and my husband on a tour in early summer 2020.

You might remember some things about early summer 2020.

By the time our tour date came around, all tours had been canceled indefinitely due to COVID. I was somewhat skeptical that the tours would ever come back, given the small scale of the operation and the presumable complexity of its security plan. But fortunately, several months ago I got an email from the tour coordinator that they were picking tours back up. She was offering the upcoming dates to the people they'd canceled on. I was able to snag a tour date in mid-August, which largely by coincidence ended up matching up neatly with a period of "funemployment" before I started a new job [1].

I had planned to hike Tikaboo Peak (viewpoint to Area 51) and visit some other national security sites that week but, owing to Nevada summer weather and my own desire to put in as little effort as possible, ended up spending most of the week luxuriating in the clingy embrace of Caesar's Rewards while riding every form of transportation I could. While I do indeed have videos of both monorail (Bombardier Mark VI, of course) and APM (Doppelmayr Cable Liner), I am doing my best to avoid dancing off the cliff and becoming a train vlogger. Instead, I am going to tell you what it's like to take a public tour of the Nevada National Security Site.

First: if you would like to do the same, you can learn about it here. According to that website tours are booked through June 2023. I would recommend that you watch that website carefully and submit your badging form as soon as more dates are announced; I would anticipate that H2 2023 tours will fill very quickly. There are also administrative details: tours depart from the National Atomic Test Museum in Las Vegas near the strip. Cameras, phones, binoculars, and bags are prohibited. The tour leaves in the morning and takes the full day. Much of this is because of the distances involved: it is about an hour drive from Las Vegas to the site, and about another hour from one end of the site to the other. I believe we were told the tour covers about 270 miles. Fortunately we were on a comfortable coach with a gregarious tour guide, former public affairs manager Darwin Morgan.

I will discuss the tour stops in no particular order, mostly because I'm not sure that I remember the order correctly. I'll also give the caveat that the NNSS staff seem to be actively working to both improve the tour and accommodate activity at the site, and so the itinerary will likely change with time.

The first item of interest in the tour comes as you approach the entrance to the NNSS, on Highway 95, a generous four-lane highway improved to its large size to accommodate the huge number of people that commuted between the site and Las Vegas during the days of active testing. Today it is mostly empty, particularly since it spends most of the distance near Las Vegas either in or adjacent to the various military reservations that make up the broader Nevada Test and Training Range (NTTR). It's important to understand that an enormous portion of the state of Nevada is reserved by the Federal Government for various defense uses. The NNSS is just one part of this sprawling complex. Area 51, for example, is not especially far from the NNSS but is not part of it. The NNSS is also not the Department of Energy's only secretive operation in southern Nevada, as the Tonopah Test Range of the NTTR is operated by Sandia National Laboratories. It is also known as Area 52 and is near its more famous numerical neighbor.

Driving out highway 95 you pass by Creech Air Force Base, a surprisingly small but densely packed Air Force installation used by UAV pilots. Our guide promised that you can almost always spot UAVs on approach or departure, and indeed it only took a moment to spot an MQ-9 Reaper performing touch-and-gos. It is reassuring that some of the military's most sophisticated aviation technology still relies on such conventional training techniques. One wonders if somewhere in a nearby building an instructor was nagging "too high, where's the needle?" Of course the airfield is less of the main feature than the many small buildings around it, as most of the pilots of Creech AFB are flying aircraft over a very different desert.

At around this point our tour guide explains a bit about the oddity of the NNSS's long commute. Most nuclear weapons installations of the era provided staff housing, but NNSS employees have long faced a rather tedious drive, and a dangerous one given the drinking culture of the time. There had been a plan to build an "atomic town" on the edge of the site for its personnel, but the extremely low water table and budget limitations prevented any serious efforts. The closest town is Indian Springs, directly across from Creech AFB, which had at the time been somewhat eschewed due to its poverty (much of the town has the feeling of a trailer park facing hard times). Of course, the large staff of Creech AFB has brought a change in fortunes and Indian Springs is now seeing quite a building boom.

A bit closer to the NNSS is Cactus Springs, which had consisted largely of a gas station and bar which was apparently popular with NNSS staff. With the end of nuclear testing came the end of the bar, and today Cactus Springs is home to the Temple of Goddess Spirituality, constructed just after the end of testing in 1993 and tended to by spiritualist Genevieve Vaughan as a shrine to the Egyptian god Sekhmet. This situation is a bit hard to parse but reminds you that the desert is full of strange and wonderful things.

On the approach to the NNSS gate, our guide points out the Desert Rock airstrip. Desert Rock was, at its peak in the '60s, a fairly large Army camp built to support operations at the NNSS---particularly the testing of nuclear effects on Army equipment and personnel. Yes, "personnel." If you have heard the stories of only partly-witting Army soldiers taking shelter from nuclear blasts in trenches only to emerge from those trenches and march for ground zero, you have heard of the Desert Rock exercises. As it turns out, the radiation exposure from these experiments was generally kept within the 3 rem safety limit established for the program. Epidemiological research has found an increase in leukemia in participants in these tests, although not one so significant that it is clearly related (there being known confounding factors, such as the very high rate of smoking in the military at the time).

Today, little is left of Desert Rock besides a field of concrete pads (from tents and temporary buildings) and an airstrip. Our guide explains that, as the closest airstrip to the NNSS, it is still maintained to some degree for emergency use. Desert Rock is more interesting to me because of my peripheral knowledge that it is the subject of conspiracy theories: Desert Rock receives very few aircraft and has nearly no support facilities, but for a time was visited somewhat regularly by a set of business jets owned by known CIA fronts. The resulting accusation that NNSS hosted some sort of black site have never been confirmed and are not, to my mind, very credible. A bit of imagination will develop more likely motivations for CIA activity at the site.

Just as the bus pulls off the highway, we pass a set of signs warning off wanderers. Our guide explains that the bold white line painted across the road here is the boundary of the reservation, and that during the era of more active anti-nuclear protest the Nye County Sheriff's Office was on hand to arrest the crowds of demonstrators that would regularly march over it. These activists were held in a set of chain-link pens just by the road while the sheriff's deputies wrote citations and were then sent back over the line to public land. This symbolic criminality, civil disobedience in perhaps the most pure form, happened regularly for many years.

Today, the specter of nuclear war is largely forgotten, and along with it the large-scale, organized anti-nuclear movement. Very few demonstrators bother to visit the NNSS, as is the case with other nuclear weapons complex sites where even major traditional protest dates like the anniversary of the bombing of Hiroshima turn out only a few people... people old enough that they had lived through the Cold War. It has always felt to me that the nuclear weapons program attained its current state of acceptance not through any actual change in public opinion but simply by attrition. Nuclear weapons have been around long enough, and with little enough impact on the world, that few can be bothered to care.

The tour enters the NNSS, as essentially everything does, at Mercury. The security checkpoint is some distance past the reservation line (this seems common at this type of installation, I suspect so that it gives errant drivers time to discover their mistake and gate runners very few excuses), and the town of Mercury is just past it. Mercury is nominally a town, and has a post office to bolster that claim, but it has no population and serves instead as the main post for the NNSS. Our guide points out the fire station, the post office, and an imposing concrete building that houses the Operations Control Center from which the whole site is run.

As we passed through Mercury our attention was called to a set of newer buildings. Our guide explained that the NNSS was having a hard time hiring and retaining staff and that the Cold War-era work environment was thought to be part of the problem. A building program had been started to transform Mercury into a more "campus-like" installation that would appeal to young people.

We stop for coffee and a bathroom at the Mercury cafeteria. I commented here to my husband that I find the "campus-like" construction effort to be a real shame. The history of the nuclear weapons program, having grown so abruptly to massive scale in the '50s and '60s, has given it a curiously consistent aesthetic. Simple rectangular buildings with cast concrete segment roofs and breeze-block screens over plate glass windows. Heavy wood paneling in an effort to add aesthetic interest. Suspended fluorescent lights with sheet metal baffles, at least a third of them dead or dying. Everything, everywhere, painted the same shade of tan.

This is, of course, a description of anything built by the army in the mid-century on a tight budget and even tighter schedule. Both in conceptual and historical terms, it is one step nicer than a row of Quonset huts. But it is a consistent look, and as a result your average Department of Energy installation looks more harmonious than a university campus with a 300-page architectural master plan. More significantly, I think it maintains a certain important spiritual connection between the weapons complex today and the Cold War. Philosophically, it might be important for the staff there now to remember that they are operating a legacy of a foregone time. Efforts to modernize the buildings, like efforts to modernize the weapons themselves, come with a degree of danger.

After our brief visit to the cafeteria, we re-boarded our bus and continued over a low ridge into the test site itself. And that's a good cliffhanger, so hold on for Part II. I'm currently in Fort Worth for a long conference, so I have quite a bit of free time and not a lot else to do. That means posting!

you are here | part 2 | part 3 | part 4

[1] I'm now with GitLab in professional services. That's right, if you spend enough money on GitLab, I might come with it! Opinions are mine and not those of my employer, except for the bad ones, which are the opinions of someone else that I've never met before and certainly did not arrive here with.


>>> 2022-08-22 preventing loss dot jp2

Programming note: Sorry for the infrequent posts lately, I have been traveling and starting a new job. Probably the next thing I post will be a report on some of that travel, which you will hopefully find interesting.

Previously on Deep Space Nine, we discussed the landscape of common retail EAS systems: electromagnetic, acousto-magnetic, and RFID. I now want to extend on this by discussing some peripheral systems that serve as part of the larger retail loss prevention technology stack. I will follow up on that by saying a bit about why none of these approaches seem to end up working that well.

Cart control

Shopping carts are fairly expensive, running around $200 to replace. Since shopping carts are attractive for moving stuff, they have a tendency to "go for a walk" and require frequent replacement. The first type of "smart cart" technology to make a widespread appearance is "cart retention" or cart anti-theft. Most Americans have probably encountered these by now, although they remain fairly uncommon in New Mexico.

While there are a number of vendors and systems, most are based around a fairly simple concept. A special wheel or wheel housing contains low-power electronics which observe for an RF tone. When the tone is detected, some type of locking mechanism activates that prevents the wheel from rotating. The wheel usually remains locked until commanded to unlock via an RF or IR device.

To form a cart perimeter, a cable is buried around the perimeter of the parking lot that acts as an antenna. The emitted power is quite low, so carts only lock when passing fairly close to the cable. In some systems, a second cable buried a bit inside of the outer emits a separate tone that commands the wheels to unlock. This makes it possible for a customer to reset a cart by dragging it a short distance back towards the store, potentially saving employee effort.

Most cart retention systems operate at low frequencies, below 9 KHz in the case of the Gatekeeper Systems offering. These low frequencies are fairly efficient with the very long antenna cables used, penetrate materials well, and best of all are below allocated spectrum... so there is no licensing required.

You can probably imagine that the "locking cart wheel" technology can be applied to a few different problems. A common form of retail loss, and one that tends to involve fairly large dollar amounts, is "push-out theft." A push-out thief loads up a cart with products and simply walks out. With well-chosen items like powdered laundry detergent it can be difficult to detect this type of theft.

One approach is aggressive traffic management in the store, using one-way gates and barriers to prevent customers exiting without passing through the checkstands. This kind of highly visible security is becoming more common but it's not completely effective... for one, having a large number of self-checkout machines tends to make it pretty easy to get through the checkstands without paying or being noticed.

A somewhat more sophisticated, and annoying, solution is the installation of a pushout prevention system like Gatekeeper's Purchek. While there can be more complexity to these systems, the basic idea is that each cart is temporarily "enabled" when a customer completes a purchase, and stays enabled for a time period like 30 minutes. Outside of that time period, any attempt to leave the store with a cart will cause that cart to lock. This should prevent anyone leaving with a cart of unpaid items.

You can probably think of a few ways to implement this, and they've probably all been done by at least one company, even the bad ones. In the case of Gatekeeper's older generation Purchek system, each checkstand seems to contain a unit that transmits a signal which starts the exit timer in the cart wheel. When the cart is pushed through the exit, a tone transmitted by a floor antenna causes it to check the exit permission timer and lock up if it is not still live.

There are variations with appreciably more complex configurations though, and Gatekeeper Systems holds a patent on a cart-to-cart and cart-to-access-point mesh networking system that can be used to apply particularly complex logic to make lock-on-exit decisions. It's not clear to me how much of the patented material is actually implemented in their commercial products right now, but certainly some of it is.

Many grocery stores now feature a panel antenna mounted near the exits facing the area approaching the doors. This panel antenna is used by the Gatekeeper door controller to communicate with the cart wheels, and it's hard to suss out the exact logical architecture of the system but it seems that the door controller can query the cart wheels for a recent historical average rotational speed and can use the history of detection of that cart wheel to determine the location history of the cart. These can be factored into the exit permission decision.

I have heard complaints of Kroger configuring the time window during which exit is enabled after paying to be as short as 60 seconds, short enough that walking slowly toward the exit (e.g. due to a disability) will consistently result in the cart locking at the doors. There is a substantial accessibility issue with many of these loss prevention technologies and vendors seldom address it in their marketing material.

Networked communication with cart wheels can also be used for various convenience use cases, like automatically counting carts in the parking lot to determine when carts need to be rounded up, and allowing a parking lot attendant to unlock all carts in a corral area at once. Nonetheless, Kroger consistently struggles to have any carts available at the entrances, but that comes down to staffing... which we'll get to in a bit.


One long-running source of loss prevention frustration is that deck at the bottom of the cart between the wheels, often called the bottom-of-basket or BOB. The way most checkstands are configured, the cashier cannot directly see this area... but it's often used for relatively expensive item like 24-packs of beer. It presents a significant opportunity for both accidental failure to ring up an item and intentional theft.

A friend who once worked in a grocery store told me that his chain had a general practice of cashiers making some comment about a fictional coworker or relative named "Bob" to warn another cashier that a customer had something on the bottom of their cart. For decades, checkstand manufacturers have offered a low-tech BOB solution consisting of a "periscope" configuration that allowed the cashier to see the foot-level area by looking in a mirror mounted under a hood near the weighscale/barcode scanner. Many stores just placed an adhesive parabolic mirror on the side of the next checkstand over that served the same purpose more simply.

These solutions are simple and effective, so of course there are options which are complex and, well, questionably effective? The Lanehawk from Datalogic is a camera and illuminator which mounts in the space most checkstands have for the lower periscope mirror. It uses machine vision to detect items in the BOB and identify them, giving the cashier a prompt that rings them up in one button press. I have seen LaneHawk installed at several stores and I have never actually seen it work. It's hard to tell if this is because of poor reliability or because of retailers starting deployment and never finishing it due to training or configuration issues, which seems to be oddly common with this type of technology.

Queue and customer volume management

Customers get irritated if they have to wait too long to check out, but idle cashiers waste money. Stores have to try to strike a balance between short wait times and high utilization rate for open checkstands.

There are two basic ways that technology can, in theory, help: first, counting queues at the checkstand can allow for a fast automatic call for more cashiers when lines start to grow. There are various systems that can do this including Gatekeeper based on counting the number of cart wheels apparently in queue for checkstands.

A second and more interesting approach is predictive queue counting. By knowing how many people entered the store and when, it's possible to predict the likely number of people who will queue to check out some time in the future. Several grocery chains have invested in Irisys's system, which uses distributed "people counting" units to track the arrival rate of customers. This data, along with potentially data on customer location in the store based on other vendor's systems, drives television screens mounted near the checkstands that display the current number of open checkstands and the number that will be required to maintain a queue depth target in 15 and 30 minutes. For some odd reason these three numbers are labeled "Lanes Open," "Action Now," and "30 Minutes," the first and third of which are inconsistent but logical and the middle of which is just bizarre. Besides this real-time feedback it also collects historical data to make long-term projections, which can be used for scheduling cashier shifts.

For some reason Irisys's marketing material repeatedly mentions the use of a "VGA display." It's unclear to me if the copy is from the '90s or just the attitude of the person who wrote it. The use of consumer televisions should reassure us that it is at least WXGA.

The data for these systems can come from many, diverse sources. Kroger stores in my area are equipped with machine-vision based people counting using multi-lens 360 degree cameras as well as Bluetooth and WiFi-sniffing people counting systems. Some machine vision is infrared, but some is visual. Some people-counters use simple multi-spot passive IR methods (somewhat like typical burglar alarm motion detectors) while others use proper imaging.

Stock management

If data collection on customer volume can be gathered automatically, what about data on stocking levels? There are products on the market that monitor shelf stocking using machine vision, but I have not personally seen them widely deployed. The principle is fairly simple, just pointing a camera at a shelf (often using fisheye optics for wide coverage) and using obvious methods to see if items are present where they should be.

Shelf stocking information can also be gathered by robots that travel the store floor observing shelves. This has been shown at a number of trade shows but I'm not sure if it's actually being done on any large scale. I tend to think that it would end up being more expensive overall than fixed cameras, considering the more complex maintenance situation.

Staff and Equipment

Given the amount of technology apparently being thrown at the problem, why is it that retail loss prevention (at least in my market) mostly seems like a confused nuisance?

I'm not an industry insider or anything, so I can only speculate. But it seems clear that insufficient staffing is the single greatest issue at the moment, and I think that's been the case since prior to COVID. Basically al of these systems are dependent on having enough staff to attend to them, and grocery stores frequently fail on this front. Kroger spent a good chunk of money installing guard podiums at the entrance of all their stores with monitors showing surveillance video, but I still haven't actually seen one staffed, presumably since it would prevent the single guard actually walking the property.

The issue has become more acute as retailers have made increasing use of two particularly labor-intensive approaches: separate, dedicated cashier stands for high-theft areas, and locking displays.

In the former system, the liquor and cosmetics sections are isolated (perhaps by awkwardly installed screen walls) and have a dedicated cashier. This cashier is presumably more able to monitor for shoplifting since they have a small assigned area, and it prevents unpurchased items from those sections circulating to parts of the store where they would be much easier to conceal.

Kroger rolled out this system over the last two years in my area and has had significant practical problems. The thing that has most stood out to me is that they have consistently laid out these areas with the expectation that the cashier stand with their back to the products. This obviously limits how vigilant the cashier can be, and moreover poses a safety concern to the staff since it reduces their situational awareness and provides an easy covert approach to potential thieves. There is news reporting that, in some areas, these checkstands have been modified in response to union complaints related to employee safety.

There are other issues yet. The checkstand obviously needs to be staffed for this system to be effective. Early on Kroger tended to leave it unstaffed most of the time, but the switch to self-checkout stands seems to have enabled more consistently posting a cashier. Second, it creates a situation in which purchased merchandise circulates around the store. This is significant, since it means that it is now fairly normal for a customer to check out and only pay for some of the items they are taking with them. This makes "theft by omission," already common at the self-checkout stands, difficult to impossible to detect. The use of "paid" stickers and stapling bags shut mitigates the issue somewhat but not entirely, since the realities of a busy retail store make it very hard to consistently adhere to and enforce these mechanisms.

In a particularly interesting gaffe (or perhaps partially implemented change in policy), Kroger stores in my region have not installed an EAS tag deactivator at the cosmetics checkstand. Cosmetics items are relatively commonly tagged, and Kroger tags many items post-manufacturing with an anti-tamper tape overlay. Due to the lack of a deactivator, though, these items now set off the EAS portal every single time they are purchased. The guard now responds to all EAS alarms by resetting them with no further investigation. Brilliant.

Nonetheless, there is obvious potential to reduce theft. I tried to find some sort of data on the efficacy of this measure but either there's little to be found or, perhaps more likely, I don't know the right terms to search for.

The other common staffing approach seen today is locking up certain items in their displays, and then requiring customers to find a staff member to have them unlocked. The staff member might walk the item to a checkstand instead of trusting the customer with it, once unlocked [1]. This method has been around for decades and is becoming increasingly common, from Walgreens (just about everything) to The Home Depot (cordless tools, certain consumables like diamond blades). The theft advantages are obvious, but the big problem is that there have to be enough employees around for a customer to reasonably be able to find someone. I am always very curious about how much sales drop when this system is introduced; I have basically stopped buying cosmetics at Walgreens because of the difficulty of getting an employee to show up.


Where does this whole thing leave us? Despite a lot of development retail loss prevention is still an unsolved problem in many ways. The greatest problem remains the trade-off between loss prevention and staffing costs: loss prevention technologies have to be cost effective, and that usually rules out the most effective designs (ubiquitous use of RFID).

Amazon Go has demonstrated the strong potential of machine vision and other machine learning technologies. This kind of ubiquitous tracking requires extensive infrastructure support, though, and major retail chains often seem to struggle with much more basic equipment installations. No doubt the management model of these companies, including franchising in some cases, is part of the difficulty, but it's also what has allowed these chains to grow to such large scale.

To some extent the increase in online shopping has obviated loss prevention technology, and there are no signs of this trend stopping. Future stores will probably lean more and more into showroom-type design, but in many cases their loss prevention efforts will lead to higher and higher friction to actually making a purchase. This seems unwise as a strategy to compete with Amazon but, well, does anyone have a good plan to compete with Amazon?

[1] An interesting factoid is that Walgreens uses expensive Medeco cylinders on the plexiglass display cases that you can force open by hand. I assume this is just to allow same-keying with other more secure enclosures, but one wonders at how much extra money these expensive cylinders have cost across the enterprise.


>>> 2022-07-21 preventing loss dot jpeg

Long time no post, or at least it feels that way! I have returned from a long vacation in a strange foreign country where the money is made of plastic, and I am slowly recovering from the tactile disturbance this caused. As tends to happen I ended up thinking a lot about the small details of international interoperation, and the issue of currency is an interesting one. I think my next post will be a bit about the mechanics of the relatively seamless ability to spend US funds in Canada or Mexico today. But first, a post that I started before I left and didn't finish until now...


You know how sometimes when you leave the grocery store, an alarm goes off which is either completely ignored or immediately reset by staff? What's up with that? Well, I can only really offer a satisfying explanation of the how, as the why is a topic of some complexity.

The whole world of tag-detection-based anti-theft technology can be broadly referred to as Electronic Article Surveillance, or EAS. One of the tricky things about understanding EAS is that, much like with proximity key systems, several significantly different technologies are in use simultaneously. There are a lot of "urban truths" about EAS that are often correct insofar as they apply to one particular EAS technology, but often not even one of the more widely used ones. The different practical and security properties of EAS systems are interesting from an evolution of technology perspective, and the cutting edge of EAS gets into some interesting areas of RF engineering.

The general principle of EAS is fairly simple: article tags are affixed to, or placed in, products that might be stolen. At the exits of a retailer, a "portal" system is installed that detects the tags. When an item is sold to a customer, a cashier uses some mechanism to either remove or deactivate the tag so that the customer can exit without causing the portal to alarm. What's less simple is the number of different ways of achieving this.

EAS systems are commonly, but mostly incorrectly, referred to as RFID. In fact, the most commonly deployed EAS use a technology which is quite dissimilar to RFID and relies on magnetic, rather than electric, field coupling. This makes it all the more interesting that EAS started out on the path to RFID, before taking rather substantial detours into the world of magnetics.


There seems to be some confusion in common sources about the nature of the first EAS, although it's agreed to have been invented by Arthur Minasy in the mid '60s. It's actually not at all difficult to find the original patent granted to Minasy in 1966, in between Minasy's many other forays (he was the type of "serial inventor" which is rarely seen today). The original Minasy design, commercialized by a company he founded called Knogo, is a simple passive circuit that receives RF energy via an antenna, rectifies it to DC, and uses that to power an oscillator that emits RF at a different frequency. This is, of course, substantially similar to the RFID concept and I find it likely that Minasy would be listed today as among the significant contributors to RFID were it not for the fact that this original technology was quickly abandoned by Knogo and is little known today. This is true to such an extent that articles about the history of EAS, if they go into any real detail on early systems, tend to describe the replacement of the Minasy system as Minasy's original invention.

There is a fundamental problem with both Minasy's early design and modern RFID in EAS applications: it requires electronic components, and electronic components are expensive. This was true in Minasy's day when individual transistors were a meaningful impact on the BOM cost, and it remains true today when EAS tags are made in tremendous volumes and fractions of a cent make a major difference.

The Minasy system, often called "RF tags" or "resonant tags," are still in use today. The relatively high cost of the tags tends to limit them to applications where they can be reused, mostly in the form of "hard tags" attached to clothing and removed on sale using a special tool. That said, it is possible to "deactivate" resonant tags. LC tags can be manufactured with an intentional susceptibility to failure when exposed to an excessively strong RF field, for example by using a capacitor which will overheat and allow the plates to short together. The tags can then be placed on a device which emits the same frequency as the detectors but at a much higher power level, resulting in intentional failure of the tag.

A more recent (but not very recent) innovation is thinner and cheaper RF tags operating at a higher frequency---typically 8.2MHz, while the original Minasy system had been tuned for 2MHz with very low precision. These 8.2MHz tags look like rectangular thin paper stickers, and when peeled up the metal foil antenna is visible underneath. They operate on the same principle as Minasy's system but are almost always deactivated by RF field rather than removed. Their thin size makes them well suited to printed materials, but they can also be applied to boxes and other packaging.


Far more common today than RF tags are a later development, the magnetic EAS tag. Magnetic tags exist in two major variants, the first having been developed by 3M in 1970. The 3M technology, commonly known by its 3M brand name "Tattle Tape," can more generically be called electromagnetic or EM EAS. EM tags rely on an interesting property of magnetic fields, or rather their interaction with magnetic materials.

Magnetic materials such as iron can be "magnetized" by exposing them to a magnetic field, causing an alignment of the magnetic dipoles of the material's molecules. During this process some of the energy of the field is consumed. Magnetic materials also have a "saturation value," which is a measure of their greatest potential to become magnetized, or the point at which no further improvement in the magnetization of the material can be achieved. For most magnetic materials, the saturation value is quite high. It is possible, though, to design materials that are magnetizable but have a very low saturation value. The most common in EAS applications is an alloy called "metglas," so called because it has a non-crystalline structure more similar to glass than metal.

When a quantity of metglas is placed in a magnetic field, it absorbs some of the energy of the field in order to become magnetized. It quickly reaches saturation and stops interacting with the field. This behavior is quite useful as it can be detected by magnetic means.

So, an EM EAS system relies on a portal with two antennas, typically placed on the two sides of the door (in multi-door situations it is common to have multiple towers which alternate receiving and transmitting). The transmitting antenna emits a magnetic field. The receiving antenna on the other side of the portal observes this field. When metglas is introduced into the field, it briefly absorbs energy and then stops when it reaches saturation. This can be observed as a brief dip in field strength at the receiving antenna. By rapidly alternating the field emitted by the transmitting antenna (essentially using it as an AC electromagnet), this effect can be checked for many times a second.

Even better, the nonlinear behavior of metglas in a magnetic field causes a number of effects in a rapidly alternating magnetic field including harmonic frequencies resulting from the repeated magnetization and demagnetization of the metglas. Modern EM EAS systems use complex DSP techniques to observe for multiple different effects caused by the low-saturation-value material, making them less susceptible to false positives. In fact, false positives in the detection of metglas are quite rare (although EAS are usually quite prone to false positives, they come from other causes which we will discuss later). Because materials with a very low saturation value are exceptionally rare in nature, the presence of rapid magnetic saturation behavior is a very strong indication of the presence of a tag.

Magnetic EAS technology becomes even more interesting when you consider the issue of deactivation. EM tags are typically manufactured with a strip of a normal ferromagnetic material placed alongside the metglas strip. If this material is magnetized, it keeps the metglas strip constantly saturated, preventing it interacting with external fields. Thus an EM tag "deactivator" simply emits a strong enough field to magnetize the ferromagnetic strip. Even better, an "activator" can emit a rapidly alternating magnetic field which will effectively "scramble" the magnetic orientations of the underlying magnetic elements in the magnetic strip, causing it to lose its magnetic field. The metglas strip will no longer be held in constant saturation and will be detected as usual.

This ability to activate and deactivate EM tags at will is unique to EM tags and is the cause of their ongoing popularity in libraries. Libraries install tattle tape permanently, usually adhering it to a middle page near the spine where it is difficult to notice. The circulation desk deactivates tags when books are checked out and activates them when books are checked in, usually using a device that just has an "activate/deactivate" switch to select between a fixed and alternating magnetic field.

If this neat property of EM tags seems a little too good to be true, well, it does have caveats. First, the ferromagnetic element in EM tags is of relatively low coercivity (e.g. magnetically "soft") to allow for easy activation and deactivation. That also makes it prone to being affected by various environmental magnetic fields, and as a direct result EM tags have a tendency to "self-activate" over time. If you have ever renewed a library book a few times and then set off the door portal when returning it, this is due to the ferromagnetic element simply losing its magnetization over weeks of exposure to electrical equipment and other ferromagnetic materials.

Second, the only aspect of EM tags that can be detected is the presence of an active one. There is no way to differentiate EM tags from each other. This can be a practical problem in circulation environments like libraries. In my city, the county library has ended use of EM tags in favor of an RFID system, but much of their inventory is still "tattle taped." The tags in these older books are now almost all active due to environmental demagnetization, and so it is more or less guaranteed that carrying a county library book into the university library will set off the portal system... on the way in and out. This kind of nuisance alarm behavior will very quickly cause staff to disregard the EAS system, and so the county library's upgrade to RFID has no doubt significantly reduced the effectiveness of the university library's system.

EM tags are most often seen in the form of "tattle tape," whether made by 3M or a competitor. These tags are long, narrow strips that are usually self-adhesive. They are thin enough to sit inconspicuously in the pages of a book, but large enough that they would be tricky to get onto the packaging of smaller products. You don't see them very often, mostly because in their most common application of library books they're placed either in the spine or on a page very close to it, where they're concealed.

EM tags cannot really be permanently deactivated without physical destruction, and they require relatively strong fields to detect. These two downsides lead to the development of a variation on magnetic EAS, called AM EAS. The label is a little confusing here as most would read "AM" and assume "amplitude modulation," but in this context it's actually an abbreviation for "acousto-magnetic." These tags rely not just on the interaction of a material with a magnetic field, but also on acoustic resonance of the material. That's pretty neat.

AM tags contain a thin strip of a material that demonstrates "magnetostriction," or a change in physical shape when exposed to a magnetic field. They are sized such that they are resonant when vibrated at a particular frequency, usually 58KHz. The AM portal system emits short bursts of a 58KHz field and then, after transmitting, uses a receiving antenna to observe for any continued 58KHz magnetic oscillation. An AM tag will continue to vibrate for a short time after the original field disappears, causing a detectable "trail" from the transmitted burst. Once again, modern portals repeat this process rapidly and use DSP methods to check for multiple indications of a real tag.

AM tags can be deactivated much like EM tags, but there are important differences. AM tags also contain a strip of a ferromagnetic material, but its function is different. The ferromagnetic strip is magnetized normally and serves as a "bias magnet." As a bias magnet, it is carefully tuned so that it offsets the magnetic anisotropy of the magnetostrictive strip---its tendency to only react to magnetic fields coming from one direction. Without this bias magnet, the AM tag cannot be reliably detected. To deactivate AM tags, the magnetic strip is demagnetized by exposing it to a strong and alternating field. AM tags are the opposite of EM tags when it comes to activation and deactivation, and so they have a bias towards deactivation. This bias is weak though: the proximity of the bias magnet to the magnetostrictive strip and the inconsistent placement of these tags makes it impractical to remagnetize or reactivate them, so they're designed for one time use only. This means that the ferromagnetic material used for the bias magnet can be of relatively high coercivity and is less affected by normal environmental fields.

I'll go into a little bit more depth on typical AM equipment, because AM is the most common EAS technology used in US retail. Virtually every retailer has at least AM portals, and you have certainly seen AM tags. AM tags are relatively thick but small compared to EM tags. They're usually in a plastic housing of perhaps 4cm long (as common as they are I couldn't find one around to measure) and a few mm thick. The largest manufacturer of AM tags is Sensormatic, and so they often have the old "hand in crosshairs" Sensormatic logo printed on them.

AM tags are ubiquitous in part because they are the accepted technology for source tagging. Source tagging is a common industry convention in which anti-theft tags are placed in products by the original manufacturer rather than the retailer. There are a few advantages to source tagging: not only does it save labor on the part of the retailer, the manufacturer can usually place the AM tag in a more discrete and difficult to tamper with location. For example, it's very common for power tools to come from the manufacturer with an AM tag inside of the tool, often adhered to the inside of the plastic molding for the handle. I recently encountered an item of clothing with an AM tag sewn into a label, although fortunately this practice isn't common... AM tags are quite rigid and not especially comfortable to wear.

Source tagging also allows for the use of EAS throughout the supply chain. Fulfillment and shipping warehouses, for example, can use AM portals to deter theft by employees, even before delivery to a retailer.

AM deactivators consist of a large coil antenna, which may be constantly active but on modern equipment usually runs in a low-power "detection mode" where it behaves similarly to a portal. The coil only runs at full power to demagnetize when it detects the presence of an AM tag. This saves a bit of money on electricity but more importantly makes the deactivator less likely to deactivate someone's credit card, which had been an occasional problem with AM deactivators despite the high coercivity of payment card magnetic strips. Some AM deactivators, probably those that have received some physical abuse, demonstrate magnetostriction of the coil itself in the form of an audible "ping" or "twang" each time the coil is powered [1].

AM portals are the most common type you see. Older AM portals (and EM portals as well) sometimes stayed unpowered until they were activated by a pressure-sensitive mat or deck between the antennas, and you might still see this in libraries in particular where continued use of EM gives little motivation to upgrade equipment, but most portals today are able to use electronic and DSP methods to detect the possible presence of tags with a very low power consumption. This sometimes takes the form of "search" and "interrogate" modes (these terms are often used in remote sensing due to its military origin and so I tend to use them), where the portal normally operates in a low power mode and the detection of any kind of magnetic interaction causes the portal to switch to a higher power mode to distinguish tags from ordinary metals.

Sensormatic is the largest manufacturer of AM portals as well as tags, so you will likely recognize the Sensormatic product lineup that varies from "big beige towers" to clear lexan sheets with coils embedded in them. Newer portal systems are relatively small, and Sensormatic even offers a "concealed" option that mounts against the door frame (not really very discretely at all) instead of requiring freestanding towers for the antennas. Of course it is limited to a fairly short range due to the small size of the antenna coils and so it doesn't seem to be that common. A more recent innovation is the installation of surveillance cameras either on the antennas or at the door frame. Sensormatic controllers can trigger video surveillance systems [2] or retrieve images from a video surveillance system, either way offering correlation of detection events with video of the person walking through.

While AM portals are mostly effective and extremely common, they do have distinct downsides. They share with the EM the property that AM tags cannot be differentiated. A common downside emerges with source-tagged items: if you purchase a source-tagged item at a retailer that does not have an AM portal, they will likely not deactivate the tag on sale. It will then set off the portals at other retailers. This is an extremely common cause of false-positive alarms. The portal also cannot indicate how many items or what types of item were detected, which makes it difficult to investigate an alarm.

As a partial mitigation, vendors including Sensormatic now offer handheld "wand" AM tag detectors with a short range. These can be used much like a wand metal detector to identify the item, or at least location on the body, that triggered the alarm. WalMarts are usually equipped with one of these in a wall-mount charging cradle near the door, but I have never actually seen one used, which foreshadows a later point I'll discuss.

Another downside is the size of AM tags. They're not exactly large, but they are thick... too thick to be easily integrated into some types of packaging. Their larger size also makes them easier to locate and remove, if they're not hidden somewhere by source tagging. Retailers that apply AM tags to items will sometimes apply a larger sticker with anti-removal features (scoring so that it will not peel away in one place) to frustrate shoplifters that simply peel off the tag, but of course this isn't entirely effective.


As I mentioned, genuine RFID has been applied to retail EAS. It remains relatively uncommon because, despite advances in low-cost manufacturing of small electronics, active RFID tags remain considerably more expensive than AM tags.

Perhaps the greatest champion of RFID EAS is WalMart, which has invested considerably in both the installation of RFID equipment (manufactured by Sensormatic) and the standardization and promulgation of RFID Electronic Product Code or EPC tags. Much like UPC (Universal Product Code) or the closely related EAN (European Article Number), EPC is an effort to assign a unique numeric ID to every product in a retail environment... but EPCs tend to be more specific than UPC, to the SKU (stockkeeping unit) level rather than price level. This means that products that are offered in multiple variations (e.g. flavors) at the same price may share the same UPC, but will have distinct EPCs.

One of the driving motivators behind this technology is its advantages for inventory management. In order to effectively track shrink (theft, spoilage, loss, damage, etc) and other "dispositions" of purchased inventory other than sale, retailers need to actually count the inventory on the floor. This is also a required step in financial auditing, insurance underwriting, and various other business processes. Basically, large stores need to actually send people out to count everything.

In practice retailers rarely handle this in house, particularly because the auditing use of this information makes it valuable to have it collected by an independent third party. For example, the use of an inventory contractor makes it more difficult for an insider (employee) who is stealing products to cover for the loss by inflating inventory counts. The largest such contractor in the US is a company called RGIS, which regularly sends an army of temp workers equipped with handheld barcode scanners into each of America's stores in order to scan every individual item on the shelves.

Sidebar which is Critical of Capitalism, You Have Been Warned

Actually the history of retail inventory is itself rather interesting as RGIS has historically been a pioneer in the design of highly usable wearable computers, and in the era before the universal use of UPC/EAN labels the incredible speed at which experienced RGIS employees could operate a belt-worn ten-key was something of a legend. Of course in one way, the invention of the barcode was a labor-saving device that ought to accelerate the inventory process greatly.

However, as potently observed by Brian Justie in The Nonmachinables (Logic Magazine), many "automation technologies" are better viewed as "labor technologies" in that their primary purpose is not actually to speed up a process but to reduce the level of operator skill required, thus making the labor more readily replaceable. This phenomenon is rather clear in the case of RGIS, where more than speeding anything up the transition to barcodes facilitated RGIS's transition to nearly complete use of short-term temp agency employees.

Since RGIS workers no longer needed to learn the skill of rapid and accurate manual entry, they no longer needed to be paid at a level that motivated them to stick around. Anecdotally, it seems that the modern barcode-based RGIS system is quite possibly slower than the earlier belt-pack ten-key, but the operator only needs the barest of training and therefore only the barest of pay or benefits. This is one of numerous cases in which advancing technology has reduced costs as promised, but by facilitating lower wages, rather than by actual improvements in efficiency.

End of leftist discourse

The EPC scheme promises to significantly accelerate the inventory process by allowing "drive-by" inventory with a good sized antenna. It also offers a significant enhancement in EAS: an EPC-based EAS system can determine exactly which items are detected and report the list of items to the operator. Even better, EPC can include a unique serial number for each item. This way, "deactivation" of the tag can be performed in an "online" manner by marking that individual item as sold. This promises significantly more accurate EAS, easier investigations of alarms, and better overall inventory control and market research insight via end-to-end lifecycle tracking of individual products.

It is also, according to a surprisingly large segment of the American population, a sure sign of the coming apocalypse. I'm sort of kidding about this but only sort of. A meaningful vein of opposition to RFID technology in public discourse has been its potential resemblance to certain aspects of the Book of Revelations. To discuss this fascinating and surprisingly important artifact of American culture would be its whole own article, but I will note the comedy of "Not Today Satan Cross Christian Religious Credit Card RFID Blocker Holder Protector Wallet Purse Sleeves Set of 4" listed on WalMart.com coming up in the same search results as "ALERT, RFID CHIP READER IS AT WALMART THE MARK OF THE BEAST IS HERE IN VIRGINIA."

A much larger problem with RFID than its satanic origins remains the cost of tags, which has lead to a lot of hesitation on the part of manufacturers and distributors to participate in RFID source-tagging schemes. WalMart is of course a large enough part of the US economy that it has a powerful ability to push its suppliers around, and WalMart just recently announced that it will mandate source-tagging with EPC for a large portion of their products. This needs to be done at the expense of the supplier, of course, although WalMart notably continues to exclude groceries from the requirement. The required categories for EPC tagging are basically all higher-value and higher-theft products, showing the practical impact of the tag cost. This same trend is seen throughout the world of EAS: the cheaper and less attractive to thieves an item is, the less likely it will have any sort of tag. The more expensive or theft-prone an item, the more likely it is to feature AM and then RFID tagging.

Although the expansion of EPC tagging at WalMart is recent, the system itself is not, and WalMart has used EPC tags on product cases and some apparel items since 2003. So have other retailers, although usually not on as large of a scale. The technology lead to enough debate around privacy (and rapture) implications that WalMart attempted to placate public concern through "transparency" by putting an "EPC In Use" decal on entry doors somewhere between the other ten regulatory decals. Of course this has never achieved any type of benefit, but I do like the design of the sticker.

Another stronghold for RFID EAS technology is the library industry. The same requirements that kept libraries on EM make RFID attractive, and so most libraries are transitioning from EM to RFID (or already have in the case of most larger libraries). Besides allowing for very accurate online tracking of checked-in/checked-out status of books, it speeds up the circulation desk (or self-service kiosk) by allowing a whole stack of books to be scanned at once. Since library books are fairly expensive and have fairly long service lives, the cost of the tags is not so much of a deterrent to libraries, and RFID tags are readily available in a thin sticker format the goes just fine inside the cover of a book.

Most RFID EAS tags are thin stickers made of either paper or plastic. They're often square or fairly close to square. Usually either peeling one up and looking underneath or shining a light through an RFID tag will reveal a spiral or otherwise packed antenna, similar to PCB traces but more often just a metal foil on a paper or plastic backing. Some RFID tags have a serial number or barcode printed on them, but many are just blank. In the case of EPCs on apparel, it's common for the RFID tag to be adhered into the middle of a two-layer paper hangtag. Libraries usually put them inside of the front or back cover, and retail products often have them placed somewhere near the UPC/EAN barcode since this gives the cashier a good idea of which side of a large box to put against the reader.

RFID EAS portals are mostly not distinguishable from AM portals, since RFID support is usually just an add-on feature to an AM system (by adding extra antenna coils in the same tower enclosure). RFID EAS systems are a lot more likely to have some sort of operator interface like a display and keypad on the wall, rather than a simple alarm, since they're able to show a list of items detected.

Unexpected part break...

This has already become quite long and I have quite a bit more to add... as sometimes happens to me, everything I've said so far is really just background to what I really wanted to discuss. Let's break this up a bit by calling this part 1, and soon I will post part 2... which will cover both cutting-edge retail loss prevention technology and the reason why both existing and brand-new systems are increasingly ineffective. There will be more criticism of capitalism, but also more weird technology!

[1] Iron is slightly magnetostrictive and this effect is the source of a lot of cases where you can "hear electricity." The 60Hz hum of large power transformers, for example, is primarily the result of the transformer windings vibrating due to magnetostriction.

[2] Support for external triggers is a longstanding feature in video surveillance systems, allowing video to be recorded on demand or just tagged with the time of events. In older systems this takes the form of a relay on the EAS system that energizes a digital input on either the video recorder or a camera (digital surveillance cameras usually include one or two digital input/output pins and a protocol to inform the recorder when their state changes). In newer systems it is more likely to be all IP.

<- newer                                                                older ->