results from the Plumbbob tests or from foreign nuclear tests. There- fore, when foreign tests are held during the series, the readings may represent fallout from these as well as from the U. S. tests. Cloud Sampling and Tracking; Airborne Monitoring \ Manned Air Force aircraft are used to take samples of atomic clouds at various altitudes, These planes are\flown through the radioactive cloud and collect "hot" samples which are flown to AEC laboratories for analysis. Air Force planes also track the atomic clouds from the Test Site for up to 600 miles, by which time they have dispersed into invisible, diffused air masses, Aircraft also are used after each shot to determine tne fallout pattern on the ground and to provide estimates of radiation intensity. Three airplanes, equipped with instruments of the type developed by Oak Ridge National Laboratory to locate uranium ore deposits from the air, take part in the airborne monitoring operation. Paths of Radioactive Clouds Many considerations affect a "go" decision on shots in Nevada, and a majority of these are related to the radioactive fallout which may result on any community near the Test Site. . Distance of -.a community from ground zero is one of the prime considerations. Following are approximated air miles between the center of Yucca Flat and the nearest communities-off-site. This list shows first the Government installations and the communities to the southeast and west of the Test Site, then moves clockwise around the Test Site. Camp Mercury, 25 miles; Indian Springs AF Base, 37 miles; Las Vegas, 90 miles; Lathrop Wells, 37 miles; Beatty, 42 miles; Goldfield, 80 miles; Tonopah, 95 miles; Warm Springs, 80 miles; Reed, (2 people) 46 miles; Nyala, 80 miles; Adaven, 75 miles; Lincoln Mine, 42 miles; Groom Mine, 24 miles; Ely, 162 miles; Pioche, 105 miles; Caliente, 90 miles; Hiko, 60 miles; Alamo, 52 miles; Glendale Junction, 90 miles; Bunkerville, 110 miles; St. George, 135 miles; Overton, 100 miles. Direction of the atomic clouds after past shots has drawn con- siderable attention after newsmen reported that some people living in or near Tonopah have-felt that a majority of the shots fired at Nevada Test Site have resulted in the clouds blowing toward Tonopah and that almost no clouds have blown toward Las Vegas. The following summany lists the 45 shots fired between January 27, 1951, and May 15, 1955, and the direction in which the major cloud was blown after the shot by the winds: , - 50 - -@ 3 A \° Ss ive Lait Re