Emily Austin, Environmental Works, Inc.
Environmental Works, Inc. (EWI) was contracted to perform emergency cleanup activities following the discovery of a pipeline release in Southwest Missouri. Upon the completion of initial response activities, EWI personnel characterized the gasoline, diesel fuel, and jet fuel release area, which impacted an initial four-acre surficial area, and seeped into karst and fracture networks in the upper bedrock with detectable impact occurring 2,800 feet from the release point.
Characterization efforts included identifying recharge points along 1,300 ft of a nearby creek, geophysical surface resistivity and GPR surveys to identify low points in the bedrock surface and anomalies to target for subsurface investigations, advancement of over 100 test borings to verify the bedrock low points and anomalies, installation of wells in the unconsolidated/epikarst/bedrock matrices, two dye trace studies, collection of an extensive soil and groundwater chemical data set, and development of a groundwater model to further evaluate contaminant transport.
The data collected during the activities above were utilized to design remedial efforts which included targeted chemical oxidation efforts in the epikarst, active and passive skimmer recovery efforts, surfactant flushing and NAPL recovery via two interceptor trenches designed to target specific surface seepage areas, and aggressive physical recovery of NAPL.
The activities above culminated with a risk assessment for the Site area, documenting no risk remains and closure can be achieved.