Fig. 1. Gas chromatography–flame ionization detector (GC–FID) chromatograms of soil from low-amendment treatments showing the distribution of Canadian Council of Ministers of the Environment (CCME) F2 (nC10–nC16 petroleum hydrocarbon [PHC] fraction) and F3 (nC16–nC34 petroleum hydrocarbon fraction) compound classes at (A) t = 0 wk, (B) t = 32 wk, planted treatment, and (C) t = 32 wk, non-planted treatment. Dotted lines are retention times for nC10, nC16, and nC34 PHC standards, respectively. The arrow in (A) shows the biosolids-derived contribution to F3.