4.1 PROJECT TRINITY. Project TRINITY was the first detonation of a nuclear weapon. The plutonium-fueled implosion device was detonated on a 100-foot tower at 0530 hours, 16 July 1945. The test, which occurred on the Alamogordo Bombing Range in south-central New Mexico, had a nuclear yield equivalent to the energy released by exploding 21 kilotons of TNT. It left a depression in the desert 2.9 meters deep and 335 meters wide (1: 1,23). } People as far away as Santa Fe and El Paso saw the brilliant light of the detonation. Windows rattled in the areas immediately surrounding the test site, waking sleeping ranchers and townspeople. To dispel any rumors that might compromise the security of this first nuclear test, the Government announced that an Army munitions dump had exploded. However, immediately after the bombing of Hiroshima, Japan, on 6 August 1945, the Government revealed to the public what had actually occurred in the New Mexico desert (1: 33). 4.1.1 Background and Objectives of Project TRINITY. The United States’ effort to develop a nuclear weapon came during World War II in response to the potential threat of a German nuclear weapon. On 6 December 1941, President Roosevelt appointed a committee to determine if the United States could construct a nuclear weapon. Six months later, the committee gave the President its report, recommending a fast-paced program that would cost up to $100 million and that might produce the weapon by July 1944 (1: 12,13). The President accepted the committee’s recommendation. The effort to construct the weapon was turned over to the War Department, which assigned the task to the Army Corps of Engineers. In September 1942, the Corps of Engineers established the Manhattan Engineer District (MED), under the command of Major General Leslie Groves, to oversee the development of a nuclear weapon. This effort was code named the "Manhattan Project" (1: 13). During the first 2 years of the Manhattan Project, work proceeded at a slow but steady pace. Significant technical problems had to be solved, and difficulties in the concentration of uranium-235 and production of plutonium, particularly the inability to process large amounts, often frustrated the 70