The Largest Apocryphal Explosion in History?

The 1982 Siberian pipeline sabotage incident is something I’ve been meaning to do a bit of research on. Yes, every bad or even mixed story in the U.S.S.R. was hushed up as best it could be by the Soviets — witness C.J. Chivers’ recent problems tracing the history of the AK-47 in The Gun — but did the incident actually happen?

For years, the CIA is said to have fed defective “stolen” technology to the Soviet Union, including gas pipeline controllers programmed to eventually trigger an explosion. I’ve seen the Siberian incident reported as the largest non-nuclear manmade explosion in history, but every source is weak and third-hand. Obviously the CIA’s and NSA’s files from the time would still be classified. It seems the best way to establish the veracity of the incident would be by speaking to senior physicians in the surrounding cities. Even if there were no deaths, the casualties from the event — if it did occur — would have been high. Burst eardrums alone would have radiated for miles.

Has anyone come upon a strong source for this story, or does it remain hidden somewhere between Soviet coverup and CIA blowback?