| This research project involved application of the intrinsic bioremediation methodology to cold temperature sites contaminated with petroleum hydrocarbons. A site investigation was carried out at two sites in Cold Lake, AB to delineate the stratigraphy, hydrogeology, microbiological setting, contaminant levels and geochemical conditions. Groundwater temperatures were approximately 8°C, which is colder than most sites where intrinsic bioremediation has been documented. At one site, dissolved benzene, toluene, ethylbenzene, and xylenes, (BTEX) contamination was confined to a shallow sandy aquifer. At the second site, BTEX contamination was present between 2--4 metres depth within a slightly weathered glacial till deposit. An assessment of the terminal electron accepting processes was undertaken and enumeration of soil microorganisms was completed. A laboratory microcosm study investigated the effects of cold temperatures on the rate and extent of substrate utilization. Results indicate that intrinsic bioremediation is viable and ongoing at these cold temperature sites. |
