An aerial radiological survey of the Double Track Site and surrounding area. Central Nevada

An aerial radiological survey of the Double Track Site was conducted in December 1993. An interim report was issued. That report described survey procedures and presented terrestrial exposure rate and wide-area-averaged plutonium isopleth plots. This letter report presents additional plutonium plots and some ``rule-of-thumb`` calculations which should help the reader to properly interpret the data presented. Attached to this report are three isopleth plots produced from the Double Track data. No one processing method provides all the answers regarding a particular surveyed area. Where peak values are most important, isopleth {number_sign}1, created from the original unsmoothed data, is the presentation of choice. Isopleth {number_sign}2, from smoothed data, is superior for the detection of areas of widespread low-level contamination. Isopleth {number_sign}3, also smoothed data, satisfied a particular early mission goal but is not as useful for cleanup operations as the other two