Table 4. (Cont.) Activity strata n Mean + S.E. (ug/gdry) Minimum concentration Maximum concentration NTS Area 13 (1957) Project 57 + .093 .076 .21 66 .16 -13 + .088 + .030 ~15 .10 -17 -16 -11 .33 -15 -14 + .059 + .13 .023 . 0092 . 36 . 26 . 86 3 -19 + .035 -11 .22 . 37 -13 -26 -25 -30 + + + + .038 .066 .13 .041 019 .077 ~12 19 .27 55 - 38 39 73 -63 75 -30 .077 .13 -15 -32 + + + + .024 .018 .049 .037 . 020 . 062 .058 21 25 -17 22 46 .98 ~32 -56 -30 .19 -15 .35 -40 + + + + .020 .011 .079 .12 -11 .13 .070 . 088 .27 -17 73 88 .27 13 64 .70 1 2 3 2 1 0 -14 .16 5 6 Total 2 2 8 4 1 -12 TTR Double Track (1963) 1 2 3 4 Total 5 2 0 4 12 TTR Clean Slate 1 (1963) 1 2 3 4 Total 6 6 2 5 19 TTR Clean Slate 2 (1963) 1 2 3 4 Total 10 5 3 7 25 TTR Clean Slate 3 (1963) 1 2. 3 4 Total a 7 3 8 _6 24 Total uranium measured by fluorimetry method for which the analysis error is about = 20 percent. c = s/x = coefficient of variation. “Data taken from Gilbert and Eberhardt, 45 1976.