Electron donor injection was performed at a former chemical manufacturing facility impacted by a complex mixture of chlorinated compounds including PCE, TCE, 1,1,2-TCA, 1,2-DCA, cis-DCE, and VC along with high concentrations of sulfate. Site managers required a comprehensive tool to monitor the performance of the electron donor injection at this complex site to ensure complete…
At a crude oil impacted site, project managers were considering MNA as a site management strategy based on favorable contaminant concentration trends and geochemistry in groundwater. However, additional lines of evidence were required. Site managers asked: “Is there direct microbial evidence to support BTEX and naphthalene biodegradation at the site?” The answer was yes. Using…
Groundwater at a former gasoline service station was impacted by leaking underground storage tanks and associated piping. Although contaminant trends and geochemistry suggested that MNA could be an appropriate site management strategy, the need for more rapid site closure led to a decision to enhance biodegradation of BTEX and MTBE aerobically with injection of an…
Site managers were considering monitored natural attenuation (MNA), biostimulation, and bioaugmentation as remediation strategies at a site impacted by a complex mixture of chlorinated hydrocarbons including PCE, TCE, 1,1,2-TCA, 1,2-DCA, cis-DCE, and VC along with high concentrations of sulfate. Site managers had several questions including: Is complete reductive dechlorination of all chlorinated solvents possible? Is…
An In Situ Microcosm study was conducted to evaluate MNA vs. enhanced aerobic bioremediation at a petroleum impacted site. Site managers asked: “Will the injection of an oxygen releasing compound stimulate BTEX biodegradation at this site?” The answer was yes. The ISM study showed conclusively that injection of the an oxygen releasing compound at the site will increase…
A pilot study was conducted at a site where electron donor was injected into groundwater impacted by a mixture of chlorinated solvents. Site managers asked two questions: “Did the electron donor injection stimulate reductive dechlorination?” and “Did injection of the electron donor also increase the potential for abiotic dechlorination through the generation of biogenic FeS?”…
A homeowner dependent on a domestic water well suddenly saw an accumulation of a black precipitant clogging the pre-filter of their water treatment system. Two years previous to this observation there was a release of gas condensate hydrocarbons and saltwater upgradient of their property. The homeowner and their attorneys asked “Is this black precipitant evidence…
QuantArray®-MIC was performed on swab samples from internally pitted and adjacent non-pitted areas of pipeline components as part of a multiple lines of evidence approach to evaluate microbiologically influenced corrosion (MIC). Concentrations of Total Bacteria, Total Archaea, sulfate reducing bacteria (SRB), methanogens, and other microorganisms commonly implicated in MIC were orders of magnitude greater in the…
Mass reduction by DPE and SVE at a hydrocarbon- and MTBE-impacted site had become uneconomical. Site managers asked: “Can we transition to MNA?” The answer, for the most part, was yes. Post SVE, hydrocarbon and MTBE concentrations showed decreasing trends in most monitoring wells. Additional strong lines of evidence for in situ biodegradation of benzene and MTBE under…
This brochure provides an overview of the molecular microbiological methods (MMMs) relevant to addressing microbiologically influenced corrosion (MIC) in the context of midstream oil and gas operations. Relevant applications for CENSUS® qPCR, QuantArray®-MIC and next generation sequencing are discussed.