This case study reviews a gasoline service station near the Mississippi River in central-eastern Louisiana that was contaminated with petroleum hydrocarbons (PHCs) detected in soil and groundwater. Further investigation phases were performed to define the magnitude and extent of the PHC plume, confined to predominantly fine-grained soils (i.e., silt and clay) in the upper 15 feet below ground surface (bgs). In 2015, PPM Consultants, Inc. (PPM) submitted a Corrective Action Plan (CAP) to the Louisiana Department of Environmental Quality (LDEQ) to remediate benzene (i.e., the primary PHC of concern), in soil and groundwater. In the CAP, PPM proposed an in situ chemical oxidation (ISCO) and aerobic bioremediation treatment approach utilizing PersulfOx® and ORC Advanced®. The ISCO to bio treatment approach was nearly 50% more cost-effective than the installation of either dual-phase extraction or ozone sparging systems, two possible approaches considered by PPM prior to determining the final remedy.

Gas station site

Case study highlights:

  • Collaboration between PPM Consultants and REGENESIS resulted in substantial cost savings while achieving the no further action goal.
  • REGENESIS Remediation Services implemented a highly-controlled injection program.
  • Following the application and subsequent monitoring, the treatment objective was met.