| Air Concentration Summaries from |
| Environmental Surveillance Reports |
| TA-53 |
| ------------------------------------------------------ |
| Calendar | Total Air | Total # | # Samples | Air Concentrations |
| Year | Volume (m3) | Samples | < MDA | ------------------------------------------------------ |
| Min | Max | Mean | Std.Dev. | Units |
| ==================================================================================================== |
| U |
| 1971B | 3 | 190 | 160 | 100 | pg/m3 |
| 1972 | 120 | 70 | pg/m3 |
| 1973 | 200 | 100 | 100 | pg/m3 |
| 1973 | 100 | 100 | 40 | pg/m3 |
| 1974 | 230 | 110 | 30 | pg/m3 |
| 1975 | 22 | 94 | 53 | 6 | pg/m3 |
| 1976 | 100189 | 4 | 34 | 107 | 62 | 8 | pg/m3 |
| 1977 | 88362 | 4 | 56 | 189 | 108 | 145 | pg/m3 |
| 1978 | 81191 | 4 | 1 | 16 | 61 | 40 | 58 | pg/m3 |
| 1979 | 82759 | 4 | 43 | 97 | 79 | 76 | pg/m3 |
| 1980 | 89641 | 4 | 56 | 104 | 83 | 22 | pg/m3 |
| 1981 | 49899 | 4 | 2 | -1.9 | 53 | 26 | 22 | pg/m3 |
| 1982 | 84524 | 4 | 27 | 74 | 53 | 22 | pg/m3 |
| 1983 | 86289 | 4 | 12 | 23 | 25 | 14 | pg/m3 |
| 1984 | 93019 | 4 | 9.9 | 74 | 33 | 28 | pg/m3 |
| 1985 | 110329 | 4 | 16.3 | 42.6 | 26.8 | 11.3 | pg/m3 |
| 1986 | 102235 | 4 | 19.4 | 41.5 | 30.8 | 10.1 | pg/m3 |
| 1987 | 104546 | 4 | 26.8 | 34.5 | 30.3 | 3.2 | pg/m3 |
| 1988 | 68653 | 4 | 48.8 | 66.8 | 57.3 | 8.5 | pg/m3 |
| 1989 | 80440 | 4 | 49.9 | 92.4 | 71.8 | 18.1 | pg/m3 |
| 1990 | 73440.51 | 4 | 33.7 | 160.1 | 70.8 | 59.8 | pg/m3 |
| 1991 | 69279 | 3 | 22.5 | 62.3 | 39.1 | 3.9 | pg/m3 |
| 1992 | 74341 | 4 | 31.4 | 544.1 | 178.4 | 41.9 | pg/m3 |
| U-234 |
| 1992 | 74341 | 4 | 8.3 | 38.6 | 17.1 | 6.6 | aCi/m3 |
| 1993 | 28500 | 2 | 8 | 9.9 | 8.9 | aCi/m3 |
| 1994 | 55300 | 4 | 4.4 | 9.4 | 7.1 | 5 | aCi/m3 |
| 1995 | 4 | 4.2 | 10.4 | 7 | 6.3 | aCi/m3 |
| ===================================================================================================== |
| Tuesday, December 24, 2002 | Page 7 of 8 |