from the Watertown strip with logistical and technical support by the Air Weather Service of the U.S. Air Force to make weather observations at heights that cannot be attained by most aircraft." In fact, U-2 aircraft at Waterown were painted in NACA markings to protect the cover story in the event that one of them was lost off-site.
Under the cloud
Shot STOKES was fired from a balloon above Area 7. It exploded with a yield of 19 kilotons. The fallout cloud passed through the Groom Lake area.
Prior to the construction of the Watertown facility, there were 32 atmospheric nuclear tests at the NTS. Since they were detonated when the wind was blowing generally northeast, the shots usually deposited fallout on the Groom Lake area. In 1955 and 1956, there were 14 more. The 1957 test series, Operation Plumbbob, included 24 nuclear detonations and six safety experiments (three of which had a slight nuclear yield). These tests frequently required the evacuation of personnel from Watertown, interrupting flight test and crew training operations.
A memo from Brig. Gen. Alfred D. Starbird in the Department of Energy (DOE) historical archives describes a teleconference regarding Watertown exposure to fallout during the 1957 test series. According to the memo, the "Watertown agreement requires that personnel evacuate, if necessary, to permit [the] test device to be fired." It was also cautioned that "expected fallout on Watertown from a given shot should be limited so as to permit re-entry of personnel within three to four weeks without danger of exposure exceeding the established off-site rad-safe [radiation safety] criteria, and with understanding that evacuation for a later shot may be required."
It was requested that this position be passed on to the Nevada Test Organization planning board, and that the Board should determine "delays in firing which may result, if any, from Watertown consideration," and "maximum tolerable fallout on Watertown under stated conditions." At this time, the Groom Lake facility was only being used for the U-2, and was expected to be deactivated as the aircraft and crews were dispersed to overseas bases for operational missions. The memo states: "Latest info here indicates Watertown will continue operation through June 30, 1957, and possibly for an additional year thereafter." The evacuations must have been inconvenient to Watertown personnel, as they would have had a severe impact on flight test and training schedules.