Spycraft - Melton [117]
Targets were not the only ones displeased with tech mistakes. On a seemingly routine operation, the techs made an uneventful entry into a commercial building and began drilling the starter hole into the common wall with a Soviet trade mission. Suddenly, the drill bit broke through, creating a gaping hole in the adjoining room. With no way to repair the damage, the best that the techs could manage was to patch their side of the wall and retreat to the local chief of station’s office to report their problem.
“We have a nice hole in the wall for audio,” the head tech reported.
“Good,” the COS replied, “very, very good.”
“Well, what I mean,” explained the tech, “is that we broke through with a really nice big hole.”
The chief went ballistic. “Get out of my country and never show your face here again!” He spoke the order loudly enough that the techs heard each word and didn’t even think of putting up an argument.
“I guess that tells us something about the lack of a sense of humor some of these guys have,” whispered one of the team members.
A few weeks later, after the chief calmed down, another visiting OTS officer suggested that, given the importance of the target, another attempt was merited. The chief demanded and received assurances a similar mistake would not be made. The installation went off without a problem.
Listening to the live audio a few days later, the techs heard sounds of a work crew coming into the room. Not clear from the conversation was whether this was a sweep team or construction crew, but they were obviously looking carefully at the walls. The techs held their breath, waiting for what would happen next.
“Look at this,” one guy said.
“Damn, what’s that hole? That shouldn’t be here,” came the reply. “Well, we better get rid of it.”
With relief, the techs listened as the conscientious construction crew repaired the wall with the three-eighths-inch hole, never noticing the pinhole a few feet away. This time even the chief of station was amused.
To avoid the disasters of noise or breakthrough, techs would often drill just a few revolutions per minute. To create the pinhole, they would slowly twist a six-inch cylinder shaft that held the tiny bit with thumb and forefinger, applying little, if any, pressure, and letting the bit pull itself through the final fraction of an inch.
The problem of measuring the thickness of the remaining wall between the end of a drill bit and “breakthrough” was partially solved by one of the OTS’s cleverest tools, the Backscatter Gauge.8 While the basic technology employed was not new, its covert application was a model of ingenuity. The principle behind backscatter technology is nuclear science. A tiny radioactive source emits a steady pulse of gamma rays, bouncing them off an object while a reader contained in the unit measures the number of pulses that bounce back. A thick material will repel more gamma rays than thin material. The gauge calculates the percentage of the returning rays against the number emitted. For example, an object that bounces back 50 percent of the pulses is twice as thick as one that returns only 25 percent. A more sophisticated version of the technology later evolved into security devices used to scan baggage and individuals at airport checkpoints. In this configuration, with advanced signal processing, the returned gamma rays actually paint a picture, similar to that of an x-ray.
When OTS adapted the technology for clandestine purposes in the 1970s, backscatter was widely used in industrial applications, primarily for quality control. “It was being used in paper mills to keep the thickness or consistency of paper constant,” explained Martin