MEAN ANNUAL Pu-239 AND Pu-248 CONCENTRATIONS IN BREATHABLE AIR DURING THE . PERIOD 1966 - 1980 CONCENTRATIONS AT STATION (pCi x m> x 197°) YEAR 2-1 2-2 P 3-1 1966 1.13 1.21 0.4 6.74 1967 G41 11.94 6.1. 8.35 1968 5.19 9.59 9.07 8.09 1969 4.35 3.84 0.07 8.38 1978 9.16 5.86 1971 5.96 5.69 1972 8.28 8.05 1973 2.08 8.06 1974 9.22 9.11 1975 0.44 9.95 1976 g.12 8.05 1977 8.32 6.15 1978 9.45 9.6 1979 9.52 15 1980 9.89 9.76 :