-6These data extrapolate to a beta contribution of about 30%. Three stands, located in areas of minimal or no ground cover, resulted in the lower two curves of Figure 3; the beta contribution varies from about 50% (lower curve) in a completely bare location, to about 40% in two areas with minimal ground cover. Although the general shape of the attenuation curves is similar for all ground cover conditions, there is considerable difference in relative response for greater than about 1000 mg/cm” 2 of absorber. The difference in beta attenuation between thick and medium ground cover js not so distinct as the difference between medium and minimal ground cover, indicating that a relatively small amount of ground cover reduces the beta contribution at ] meter considerably (i.e., from 50% at bare locations down to about 30% at medium locations, then down only to 20% at thickly vegetated locations). The ratios of TLD responses for attenuated dosimeters were determined at 80 locations in an attempt to correlate these ratios with vegetation (Figure 4). The measured contributon of beta or low-energy gamma to the total exposure rate varied between 16% and 59%, with a median of 29%. Although a wide variety and extent of ground cover were represented in these 80 locations, the deviation in the data is less than 13% at l0y suggesting that a median of 29% of the total dose rate at 1 meter can be used with sufficient accuracy for estimates of doses to the skin and eyes of future inhabitants. Attempts to categorize TLD locations with respect to vegetation and beta contribution were unsuccessful, partly due to differing concentrations of 90 ~“Sr and 1376, in the soil, but largely due to changes in the nature and extent of vegetation over a three-month period. Locations originally categorized as thickly vegetated did have a slightly lower median beta ratio (25%), but these differences are not large enough to warrant categorizing projected beta doses according to vegetation. I00824b