FIG. 1.

Percentage mineralization of [1,2-¹⁴C]DCE to ¹⁴CO₂ in microcosms containing material collected from the surface fill (depth, 1 m), the shallow aquifer (depth, 3 to 5 m) and the intermediate aquifer (depth, 8 to 10 m). Experimental data are means ± standard deviations for duplicate microcosms, and the control data are from a single sterile control microcosm. For each material studied, superscript letters indicate statistically significantly different final mean ¹⁴CO₂ recoveries according to the Kruskal-Wallis one-way analysis of variance on ranks (P < 0.05).