Intrinsic remediation of fuel hydrocarbons in low-temperature groundwater environments

Geochemical trends and biodegradation rates observed at five petroleum-contaminated sites in Alaska and northern Michigan suggest that both aerobic and anaerobic biodegradation are removing petroleum hydrocarbons dissolved in low-temperature groundwater. Based onsite-specific groundwater geochemistry and expressed assimilative capacity estimates, anaerobic biodegradation dominates the removal of contaminants at these sites, mainly through sulfate reduction or methanogenesis. Despite the cold groundwater environments of Alaska (typically below 10 C) and northern Michigan (typically below 15 C), estimated biodegradation rates for benzene, toluene, ethylbenzene, and xylenes (BTEX) approach or exceed 1% per day. The importance of these results is that they broaden the demonstrated applicability of intrinsic remediation from sites in warmer, temperate climates to include those in colder regions