TABLE 2.
Final distribution of 14C radioactivity in anoxic bed sediment microcosms after 77 daysa
| Sediment source | Treatment | Compound |
14C distribution (%)
|
|
|---|---|---|---|---|
| Experimental | Control | |||
| Charleston | NO3 amended | MTBE | 70 ± 1 | 97 |
| TBA | NDb | 3 | ||
| CO2 | 26 ± 10 | ND | ||
| CH4 | ND | ND | ||
| Total recovery | 96 ± 10 | 100 | ||
| Unamended | MTBE | 85 ± 5 | 91 | |
| TBA | 10 ± 2 | 3 | ||
| CO2 | 3 ± 3 | ND | ||
| CH4 | 1 ± 1 | ND | ||
| Total recovery | 99 ± 5 | 94 | ||
| Pensacola | NO3 amended | MTBE | 71 ± 4 | 94 |
| TBA | 1 ± 1 | 4 | ||
| CO2 | 23 ± 5 | ND | ||
| CH4 | ND | ND | ||
| Total recovery | 95 ± 5 | 98 | ||
| Unamended | MTBE | 78 ± 4 | 101 | |
| TBA | 9 ± 2 | 4 | ||
| CO2 | 5 ± 2 | ND | ||
| CH4 | 5 ± 1 | ND | ||
| Total recovery | 97 ± 4 | 105 | ||
a
No radiolabeled C1 to C4 organic acids were detected in this study. For each treatment, experimental data are means ± SD for triplicate microcosms, and control data are from a single microcosm.
b
ND, not detected. The MDL for radiometric detection was equivalent to 1% final recovery.