NEVADA TEST SITE

The 23rd scheduled shot in the Plumbbob series will be an experimental device designed by Livermore Laboratory which is now scheduled to be ready for firing at 5:30 a.m. PDT Monday, Sept. 23.

It will be suspended beneath a 75-foot diameter balloon at approximately 1500 feet above Area 9 of Yucca Flat. It's code name is Charleston, for the peak in the Spring Mountains near Las Vegas.

While this is an experimental device with a wide range of possible yields, the Laboratory has determined that the most probably yield will be above nominal. Primarily because of the high position of the device and secondarily because the yield may be above nominal, road blocks will be established again on highways 93, 95 and 25 beginning about 45 minutes before shot time to halt traffic and assure that vehicle occupants are not looking toward the detonation. Other observers who are in a location with direct line-of-sight to the fireball are cautioned to look the other way at shot time.

There will be 17 experiments on the sequence timer. Twenty aircraft will participate in technical and other support roles. There will be no military or civil effects participation. Rockets will be used after the detonation to sample the early cloud.