-4fastened on top for improved protection from the environment (rainfall, dirt). A calibration of the dosimeters was made with a to deployment. 137 Cs source prior At each of 80 locations, two TLD badge sets were positioned ] meter above the ground on a slotted crossbar mounted on a wooden stake. One of these sets at each location was surrounded with an additional 860 mg/cm* aluminum attenuator to allow only the energetic gamma component to be recorded by the dosimeter. An array of TLD dosimeter badges surrounded by various attenuator thicknesses was also positioned at a height of |] meter at each of seven locations to determine the effect of ground cover on the beta contribution. An aluminum framework 46 cm wide, 92 cm long and 1 meter high was used for these experimental stands. Three pieces of aluminum bar stock were each drilled to house four sets of TLD badges with various amounts of aluminum shielding, and bolted across the top of each stand. Twelve TLD badge sets were therefore used at each location, shielded top and bottom by various aluminum absorber thicknesses. Control TLD sets were stored inside a lead pig on a southern island with minimal radioactivity. All TLD badge sets were retrieved approximately three months later and transported back to Lawrence Livermore National Laboratory inside a lead pig for evaluation. A second calibration was carried out before evaluation to determine fading and transit exposure. A pancake GM probe with a 7.62 cm diameter thin window, lead gamma shield and digital readout was used for comparative purposes. Measurements with this portable active instrument were made at 34 locations. At each location, two measurements were made at 1 meter height; one with no attenuator and one with an 860 mg/cm* attenuator over the window. 9008294