Achievement

LeFevre, G., Novak, P., Hozalski, R. Quantification of petroleum hydrocarbon residual and biodegradation functional genes in rain garden field sites. Proceedings to EWRI/ASCE International LID Conference 2010 San Francisco, CA.

Abstract: Stormwater is known to convey oils, greases, and polycyclic aromatic hydrocarbons from impervious surfaces, and previous studies have indicated that bioretention is effective at removal of these pollutants. Concern has been expressed that such petrochemicals in stormwater could accumulate in the soil during infiltration and create 'pollutant depots' in raingardens. Soil samples were collected from 56 raingardens and 4 upland locations and total petroleum hydrocarbons (TPH) and bacterial DNA were extracted and quantified. TPH was detected in many of the raingarden soil samples, but at low levels; upland samples were uniformly non-detect. Overall, we observed that a substantial 'toxic depot' effect did not occur.