| Air Concentration Summaries from |
| Environmental Surveillance Reports |
| Bayo Sewage Treatment Plant (STP) |
| ------------------------------------------------------ |
| Calendar | Total Air | Total # | # Samples | Air Concentrations |
| Year | Volume (m3) | Samples | < MDA | ------------------------------------------------------ |
| Min | Max | Mean | Std.Dev. | Units |
| ==================================================================================================== |
| Alpha |
| 1971B | 16 | 31 | 2.6 | 4 | fCi/m3 |
| 1972 | 7.6 | 1.6 | 0.4 | fCi/m3 |
| 1973 | 4.1 | 1.1 | 0.4 | fCi/m3 |
| 1974 | 0.4 | 3.1 | 1.2 | 0.1 | fCi/m3 |
| 1975 | 0.4 | 2.5 | 1.1 | 0.1 | fCi/m3 |
| 1976 | 99172 | 26 | 1 | 0.1 | 3.5 | 1.1 | 0.2 | fCi/m3 |
| 1977 | 89959 | 19 | 3 | -2.7 | 2.1 | 1.1 | 2.1 | fCi/m3 |
| 1978 | 89190 | 13 | 3 | 0 | 3 | 1.1 | 2 | fCi/m3 |
| 1979 | 93938 | 12 | 0.3 | 5.3 | 2 | 2.8 | fCi/m3 |
| 1980 | 87404 | 12 | 1.1 | 6.8 | 2.7 | 0.9 | fCi/m3 |
| 1981 | 48713 | 12 | 1 | 0.1 | 8.2 | 3.5 | 1.3 | fCi/m3 |
| 1982 | 83388 | 12 | 1.4 | 4.5 | 3 | 0.5 | fCi/m3 |
| Am-241 |
| 1973 | 3 | 3 | 3 | aCi/m3 |
| 1975 | 3 | 2 | 2 | aCi/m3 |
| 1977 | 101268 | 4 | 3 | 0.5 | 19 | 6.1 | 18 | aCi/m3 |
| 1978 | 68754 | 3 | 3 | -1.9 | 0.6 | -0.3 | 2.8 | aCi/m3 |
| 1979 | 90449 | 4 | 4 | -1.1 | 1.2 | -0.7 | 1.8 | aCi/m3 |
| 1980 | 86404 | 4 | 4 | -1.8 | 1 | -0.7 | 1.3 | aCi/m3 |
| 1981 | 48713 | 4 | 4 | 0.8 | 1.4 | 1.1 | 0.5 | aCi/m3 |
| 1982 | 83388 | 4 | 4 | 0 | 1 | 0.1 | 0.2 | aCi/m3 |
| 1986 | 42782 | 2 | 2.8 | 5.4 | 4.1 | aCi/m3 |
| 1987 | 66204 | 3 | 3 | 0.3 | 1.7 | 1 | 0.7 | aCi/m3 |
| ===================================================================================================== |
| Tuesday, December 24, 2002 | Page 1 of 6 |