Brown, B.
Florida Remediation Conference 2018, 5-6 December [Abstract only] 2018

An enhanced anaerobic bioremediation (EAB) system was used at a former industrial manufacturing facility in Orlando to address high concentrations (>100,000 µg/L) of chlorinated solvents in the surficial aquifer. One well showed a concentration as high as 2,000,000 µg/L. Source-zone contamination was remediated using EAB with potassium lactate and groundwater circulation to biostimulate indigenous Dehalococcoides bacteria. As concentrations approached groundwater cleanup target levels, zero-valent iron and in situ chemical oxidation via sodium persulfate injections were used in zones of contamination outside the EAB treatment area. Within 33 months, total contaminant mass fell from an estimated 2,800 lbs to <30 lbs, with molar concentrations of all VOCs decreasing steadily. Concentrations in the source area decreased from >100,000 µg/L to <10 µg/L at multiple locations. ISCO injections further reduced concentrations outside the EAB treatment area. Post-active remediation monitoring has shown concentrations at or below treatment goals. See information on earlier results for this project in an article at http://pubs.awma.org/gsearch/em/2010/4/turner.pdf.