Scientists oversaw each observation shelter until detonation, upon which a medical doctor familiar with radiation took over. At first there was no sign of danger. Then suddenly, the instruments at North 10,000 started clicking. The order to evacuate was given. Cars and trucks raced past West 10,000 on the way to base camp. It was later found to be a false alarm. Film badges showed no radiation. As the sun came up air currents swept radioactivity into the basin. Geiger counters at South 10,000 went wild, forcing the men to don gas masks. But the radioactive levels quickly moved away from the danger level.
The scientists reported feeling exhilaration that after months of intense effort, the physically imposing test actually worked. Also common was the feeling of relief at knowing they would not have to go back to the drawing board to figure out why it didn’t work. The perhaps unexpected feeling of guilt came after the two atomic bombs were dropped on Japan.
About an hour after the test, lead-lined and pressurized tanks used by Enrico Fermi and Herbert Anderson, who had been close associates in the construction of the nuclear reactor that produced the plutonium for the bomb, approached ground zero to gather soil samples. Launchers were used to send rockets with hollow heads connected to cables to collect samples from areas too hot to enter. Harold Smith, a military policeman assigned to the Engineer Detachment who was qualified as a tanker, drove Anderson’s tank. When they got near the stubs of the tower, Anderson yelled to get the hell out. The second tank with Fermi broke down.
Radiation monitors and members of the recovery team assembled a few hours after the test. As days went by, crews in protective gear retrieved neutron detectors and conducted regular monitoring and surveying of the area.
Immediately after the blast the Army covered up the test by announcing that an ammunition dump at the Alamogordo Bombing Range had exploded. Once the bombs were dropped on Japan there was no longer a need for a cover story.
Most scientists left immediately after the test. Remaining soldiers and scientists could go to ground zero when the radiation risk subsided.
The MPs threw a party for Captain Bush; many went on leave. The horses were sold at auction in Albuquerque. CPT Bush received the Legion of Merit. The soldiers got Good Conduct Medals and Letters of Commendation.
On 6 August 1945, Little Boy was dropped and exploded 1,800 feet over the city of Hiroshima, killing 100,000 people. Five years later, deaths related to the bomb had exceeded 200,000 people. On 9 August, Fat Man destroyed Nagasaki; by the end of 1945, deaths reached 140,000.
Press tours of the site with Robert Oppenheimer and MG Leslie Groves began in September 1945 after Trinity became public knowledge.
George Cremeens, a young reporter from radio station KRNT in Des Moines, Iowa visited the site with soundman Frank Lagouri in mid-September 1945. He was flown to New Mexico by CPT C. L. Rutherford of the Iowa Civil Air Patrol. He interviewed Dr. K. T. Bainbridge, Trinity Test Director, CPT Howard Bush, Base Commander and Chief of Security, and many of the soldiers performing security, life support, maintenance and technical duties at the site. Cremeens put together an award winning four-part series of 15 minutes each that aired from 24-29 September 1945 on the ABC radio network.
Ranchers rounded up their cattle; the government bought 75 and shipped them to Los Alamos and Oak Ridge for study. In Alamogordo, crowds flocked to see Arnie Gilworth’s “atomic calf,” a frost colored calf born shortly after Trinity.
Christmas of 1945 was cold and snowy; the remaining staff used their cold weather gear for the first time. By February 1946, 50 men remained, leaving in ones and twos as their enlistments expired. The Army initiated a report of survey for items not accounted for at base camp, including pieces of cutlery from the mess hall. By June, the site was vacant.
Ernest Wallis with the photo group at the site put a large picture of the blast in the window of his photo shop. It was classified; he was arrested and went to prison.
In November of 1947, Trinity site was activated for a non-nuclear test. The Army eventually tore down most of base camp. In 1967, ground zero, the ranch house, and surrounding land were declared a national historic landmark.
The monument memorializing the Trinity Test was erected in 1965 in the form of an obelisk using lava from WSMR. It is located exactly at ground zero, sitting between what had been the four legs of the 100-foot steel tower that was vaporized by the explosion. The plaque on the obelisk commemorates the world’s first nuclear bomb, detonated at 05:29:45 Mountain War Time on 16 July 1945, an event that changed the world. The fence erected in 1964 protects this national historic landmark from the Missile Range’s daily military test activities. Any residual radiation is not dangerous to visitors.
The entire 51,500-acre area, including the Schmidt-McDonald ranch house and the former base camp was designated a national historic landmark in 1975.