Underground Nuclear Testing
The signing of the Nuclear Test Ban Treaty by the Soviet Union, the United Kingdom, and the United States in August 1963 ended nuclear testing above ground, in space, or on the seas, but it allowed underground nuclear testing. This type of testing limited the amount of radioactivity released into the atmosphere and permitted both the Soviet Union and the United States to continue to refine nuclear weapons. From 1963 to 1980, the United States conducted around 400 underground tests, and the Soviets 300. Americans tended to test more refined weapons, and the Soviet more powerful ones. In 1974 an agreement was reached between the Soviet Union and the United States to limit the power of their underground tests to 150 kilotons. Other countries have also renounced atmospheric testing, but they have continued to test underground nuclear devices. The latest countries to conduct underground nuclear testing have been India, with 5 such tests between May 11 and 13, 1998, and Pakistan with 6 tests between May 29 and 30, 1998.
Even the United States decided to reinstate underground nuclear testing to check on the readiness of its nuclear arsenal. This program is called the Science Based Stockpile Stewardship (SBSS) and under the auspices of the Department of Energy (DOE) it is planning for eight “subcritical” nuclear tests underground at the Nevada test site. The first of these tests, or Rebound, took place on July 2, 1997. A series of tests continued until September 1997. Scientists from the Los Alamos National Laboratory, Sandia National Laboratories in Albuquerque, and Lawrence Livermore National Laboratory are engaged in a 10-year, $45 billion program to test nuclear weapons using high-powered lasers and supercomputers. If this