I couldn't get this info from that conspiracy site you posted, but what exactly happened at the bottom of the building where these explosive devices were palced? That's an important factor if we wish to discuss the vacuum effects of a detonation. I remember watching on TV, and the video of people standing in the street, then looking up seeing the building come down. They immediately begin running away. The cameras continued rolling after the dust coming down enveloped them. But the cameras still worked, apparently they are impervious to the EMP pulse which disrupted the power for what was it, three months?
Also, it says there were elevated levels of tritium, but it did not say how much. Also, the tritium in a nuclear device ends up as tritium rich metals like scandium. You can find lots of tritium in aircraft dials, guages, luminescent paint, luminescent devices like exit signs (not just in the aircraft, also in buildings) and even wrist watches.
Also, if this theory of a nuclear device is so sure, and the science so sound, why can I not find estimates of the explosive yield anywhere? This is important if we wish to verify the seiemic activity caused by any nuclear detonation. For example, the blast in Korea was very small, but produced a seismic reading of 4.2. It has been stated in other conspiracy theories that the heat generated would have to come from a high yield device, this would seem to be at odds where the small yield Korean detonation of 1 kt, yielded a seismic reading of 4.2, and as I said before, the seismic scale is logarithmic, so 4.2 is actually 10^18 times stronger than the highest reading of 2.3. The lowest yield possible from a nuclear device according to Robin Frost of Simon Fraser University would be 100t or 1/10 of the blast in Korea. Is it possible that a device with ten times the yield could translate to a seismic increase of 1,000,000,000,000,000,000 ?