Convenience Store - Buffalo, Missouri
Project Description
Environmental Works, Inc. (EWI) was contracted to investigate a release of unleaded gasoline related to historical underground storage tank (UST) operations. Site characterization activities included the installation of 26 shallow monitoring wells and numerous soil borings for soil and groundwater sample collection. The dissolved phase petroleum plume from the release spread across a city street and two off-site properties, covering approximately 69,000 square feet. The primary project concerns were petroleum constituents around an off-site office building (with basement) and a karst geological setting. The remedial solution was to inject a solution called BIOX® into the ground in the source area and around the off-site office building.
BIOX® is a manufactured product used to break down petroleum hydrocarbons through chemical oxidation, and also provides oxygen to enhance bioremediation. Between 50 – 60 gallons of BIOX® was injected into the subsurface at 82 locations, predominantly through 1.25 inch diameter boreholes. The injection successfully lowered the petroleum concentrations to a level where the site was able to be closed following a Tier 2 evaluation under Missouri’s Risk-Based Corrective Action (MRBCA) program.
Project Accomplishments
The project received No Further Remedial Action status in August 2008. EWI completed the project within the approved budget set by the Missouri Petroleum Storage Tank Insurance Fund (PSTIF), which significantly limited client costs. More specifically, the client was reimbursed for all costs invoiced by EWI, through PSTIF, absent the initial Insurance Fund deductible. EWI planned and executed this project in coordination with the client, MDNR, PSTIF, two off-site property owners, the City of Buffalo, and associated legal representation.
Accordingly, EWI implemented the project in accordance with the quality standards necessary to provide legally defensible data and data interpretations. EWI’s 13-year relationship with the client was built on good communication, which allowed EWI to meet the client’s needs on this sensitive project. In addition, EWI’s extensive experience with underground storage tank sites in Karst topography proved to be invaluable on this project.