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Scope
 BCI was retained by Cendant Car Rental Group to assist with the removal of the 12,000-gallon Underground Storage Tank (UST) as part of an airport parking lot construction and rental car relocation project at the Gerald R. Ford International Airport.
The tank cavity, which included approximately 1,200-cubic yards of peastone used as backfill following remediation activities on the site in response to a 1990 release, was excavated along with overconsolidated cohesive soils (clay). Samples of the peastone and sidewall samples of the clay soils were screened for volatile organic compounds (VOCs) with a photoionization detector (PID). Samples were taken from the floor of the excavation at a depth of approximately 20 feet below grade consistent with the requirements of UST closure practices.
BCI did not note any evidence of contaminant release beneath the fill material during tank removal activities, visual inspection, screening of fill material or through confirmatory sampling. BCI completed and submitted a leaking underground storage tank (LUST) closure report. The tank cavity was backfilled with clean, compacted Class 2 sand.
During demolition of the old on-site Avis building, BCI discovered residual soil impacts around the building footings and reported a new release. Impacts included stained soils, hydrocarbon odor and elevated readings with a PID. BCI excavated approximately 1,000-cubic yards of impacted soil from around the building footings and along on-site utility corridors. Verification of site remediation (VSR) samples were collected at intervals consistent with the requirements of the Michigan Department of Environmental Quality (MDEQ) sampling strategies.
BCI completed hydraulic probe borings in areas where VSR samples indicated the potential for remnant impacted soil. VSR and hydraulic probe samples were submitted for laboratory analysis of leaded gasoline parameters.
Groundwater samples also were analyzed for leaded gasoline parameters. Concentrations of lead exceeded the MDEQ drinking water criteria from a few of the samples. To address the exceedances of soil and groundwater drinking water criteria, a restrictive covenant was recorded for the property restricting the use of groundwater at the site.
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