Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!lll-winken!sun-barr!newstop!sun!amdcad!amdcad!military From: edat!brian@uunet.UU.NET (brian douglass personal account) Newsgroups: sci.military Subject: Re: How is a nuke tested underground? Message-ID: <1991May14.051526.6706@amd.com> Date: 13 May 91 18:40:18 GMT References: <1991May8.034438.11095@amd.com> <1991May10.063806.26071@amd.com> Sender: military@amd.com Organization: Electronic Data Technologies, Inc., Las Vegas, NV Lines: 69 Approved: military@amd.com From: edat!brian@uunet.UU.NET (brian douglass personal account) A couple of add ons to some of the other posters comments. Almost all tests emplace a test package above the bomb to measure things like radioactivity, particle type, etc. In the U.S., a second hole is drilled parallel to the first offset in meters (not miles). Within this hole a coax cable is placed and sealed. The resulting blast does something to the signal running through the cable, the effects of which are used to determine effective yeild. This system is called CORETEX. The horizontal shots are often used when the instrument package exceeds 6 stories in size, or when the soil composition is inappropriate for the type of measurements needed. These tunnels are cut right into a solid granite mountain. Physical containment measures can sometimes be extraordinary. As a kid, I took a science tour of the NTS back in the 70s. They showed one test designed to determine if a U.S. communications sattellite could withstand the EMP and radiation of nuclear explosion within 1500 feet in outerspace. They drilled a hole, with approximately a 6 foot diamater. The bomb was emplaced at the bottom, and a tube run all the back to the surface where it connected to a cylindrical chamber about 30 feet in diameter. Hung from bungy cords inside the tank was an actual defense comm-sat fully operational. They even had a lamp to simulate the sun. Then this entire enviroment, chamber, tube and all was evacuated to 10^-17 TOR to simulate a geosynchronous orbit. They said then it was the largest manmade vacuum ever. Once the trigger signal set off the blast the signal (dc or something) also set off containment devices, such as crushers, conventional explosives, doors, etc, the radiation nanoseconds behind the trigger. Eventually, between the tube and the tank, two one-ton doors closed in 1 micro-second, having been gas charged to 20 atmospheres. Once closed, the tank was separated from the tube and pulled (the sled was tractored) by two 20,000 hp wenches, one diesel, one electric, before the caldier set in. The neat thing was that all this equipment was common equipment they had from earlier tests. Most of the testing is not theoretical testing (20%), as I understand, but rather operational (80%) testing of warheads or warhead design. As far as the properties of nuclear weapons, that is supposed to be pretty well understood. As a side note, 3 years ago the Joint Verification Experiment was held where U.S. experts went to Semipalytinsk (?) and tested the yeild of a Soviet nuclear weapon using CORETEX, while a Soviet team came here and measured a U.S. weapon using Seismic means. DOE spokesmen said the tests were successful. As I understand it now, the JVE is going active again with the goal being permanent on site verification of the threshold test ban treaty. Someone also said the site in Semipalitynsk (maybe this one) was closed. I understand that both are active, and that the second in Siberia is possibly for different soil composition reasons. Afterall the first JVE was in 88, well after Chernobyl. But that is a guess. It is hard to differentiate this conversation between weapons testing, EE science, poly sci and all else, but then again, who ever thought nuclear weapons were just bigger bombs in a smaller package? :-; Brian Douglass Voice: 702-361-1510 X311 Electronic Data Technologies FAX #: 702-361-2545 1085 Palms Airport Drive brian@edat.uucp Las Vegas, NV 89119-3715