|Ecovac Services / Projects / Railroad /
South Bend, Indiana (Railroad site)
Separate-phase hydrocarbons (SPH) present in 7 monitor/recovery wells ranging in thicknesses from 0.02 to 1.17 feet
Fine to medium sand with some coarse gravel
SURFAC® PILOT/TREATABILITY TESTING:
SURFAC® Pilot Testing was conducted to collect data to implement EcoVac Services’ patented SURFAC® process. SURFAC® is proposed due to its proven cost effective results, the site’s limited access, and failure of current remediation activities to remove SPH. EcoVac’s treatability study predicts that SURFAC® will result in a 96% contaminant (diesel) removal at this site
EcoVac Services was retained to remove SPH from the site after the Indiana Department of Environmental Management (IDEM) required a more aggressive cleanup approach. A remediation system consisting of two recovery wells containing skimmer pumps has been utilized at the site for a number of years.
The site consists of fine to medium sand with some coarse gravel a shallow perched zone at about ten feet below grade. The aquifer is present at approximately 7 to 20 feet below grade. Groundwater is present at approximately 45 feet below grade beneath a railroad embankment.
EcoVac Services was contracted to implement SURFAC® at this site due to the challenging conditions (i.e. geology/hydrogeology conditions, extent of SPH plume, ongoing presence of SPH despite previous and current remedial activities, and limited site access).
EcoVac Services’ patented SURFAC® process is the combination of dual-phase/multi-phase extraction and surfactant injection.
EcoVac Services also conducted a treatability and SURFAC® simulation study using site media. The study indicated that SURFAC® will result in a 96% diesel fuel recovery at this site.
Additional EFR® (mobile dual-phase/multi-phase extraction) events are proposed for the site until SPH thicknesses are reduced to approximately <0.5 feet/well. SURFAC® will be implemented at this site once SPH thicknesses have decreased and the SPH plume has been further delineated.
A three-day SURFAC® Pilot Test was conducted at the site to (1) determine the surfactant injection volumes and sequencing, (2) achieve contaminant removal by the multi-phase/dual-phase extraction process, (3) reduce the aerial and vertical extent of the plumes, (4) assess the potential need for additional injection wells, (5) determine if additional EFR® events are necessary prior to surfactant injection, and (6) determine the duration of the surfactant injection.