CLEARING EXPERIMENT EXPOSURE RATES (ur/hr) -Radius of Cleared Area Q' 10' 20' 30' The slight +87 C5 S°Co 47.2 48.6 50.8 52.2 5.2 5.2 5.5 5.7 185 oh Total 9.1 8.6 8.0 8.5 Aa 61.5 62.4 64. 3 66.4 increase in the total cf the 187 as, 59.0 59.0 59.9 60.5 Sao. and +25 oh exposure rates indicates that there is possibly some increase in the unscattered gamma radiation affecting our partial exposure rate estimates, but there is a corresponding reduction in the scattered radiation and thus little effect on the total exposure rate. The more important effect of the vegetation seems to be to enhance scattering of the radiation from emitters in the soil thereby producing a slightly softer energy spectrum. This effect more than con- pensates for the increase in exposure rate at the detector due to radiation originating in the vegetation itself. The quantity of vegetation removed was staggering. As the brush was removed from the area, it was identified and weighed. These statistics are given below. VEGETATION REMOVED IN CLEARING EXPERIMENT Area Scaevola Dedonea Litter Pounds of Aerial Portions 10 £t. radius 10 - 20 ft. radius 20 - 30 ft. radius 593 1717 33 112 59 364 5212 212 809 2902 Total - 25 - 7 386