In the standard equipment method, the survey is making by taking readings with a standard military portable radiac instrument which is carried inside the aircraft while flying over the contaminated area. This rethod requires a minimm of preparation. and equipment and may be suitatie for certain situations where large errors may be tolerated. In the long-range method, the survey is carried out by flying a grid pattern and measuring intensities with a special, fast response detector carried inside the aircraft and telemetering the data back to a plotting station on the ground. This method is best suited for rapid surveys of lerge areas when only the general level and extent of fallout activity are sesired. BE ST AVAILABLE Co py CWLR ~ 2176 - A HISTORICAL DISCUSSION OF CONTAMINATING EVENTS OCCURRING DURING U. S. ATOMIC TEST OPERATIONS (U). Luther M. Hardin, David W. Einsel, Jr., Harold E. Shaw, and Robert P. Beckelheimer, October 1957. SECRET-RESTRICTED DATA, Technical Report A total of 83 nuclear weapons or devices has been detonated by the United States to date (March 1957}.* Of these bursts, 51 can be classified as contaminating events. A chronology of all United States nuclear detczrations is given with dates, yields, locations, heights of burst, and ixdications whether a significant portion of the fireball was subtended by the land or water surface. The extent of the contaminated area and the radiation intensities produced by muclear detonation depend upon the height of burst, the total yield, the wind velocity {up to altitudes equal to cloud height), and the specific preverties of the surface over or under which the burst occurs, The 51 contaminating events are discussed by type; land surface, nearsurface land, underground, water surface, near-surface water, and underwater. (U) Icealized dose-rate contours are presented for both kilotonand megaton-yield weapons. These patterns are useful for predicting the area and extent of fallout patterns. CWLR - 2222 - A GEIGER COUNTER FOR LARGE DIAMETER SOURCES (U). Leonard Bird, John Kinch, June 1958. UNCLASSIFIED (vu) A 2x flow-type Geiger Muller counter with a 4-3/4 inch diameter window is described. REST ATO RG The adaptation of this counter to 4x counting is discussé: TA 954