Client: MDEQ Project Management Firm - Roy F. Weston
Site Location: 2730 Orchard Beach Road, Cheboygan, Michigan
Project Dates: 2/00 - Present
Sagasser & Associates, Inc. was subcontracted by a State of Michigan Contract Management firm to complete ARA, SI and FFS of a known contaminated facility. The project involved identification of potentially contributing sources to the LUST site contamination, assessing the impact to residential wells, vapor monitoring of indoor air and substructures, soil and groundwater contaminant delineation, and free product delineation.
The Site consisted of a former greenhouse/landscaping facility with diesel and gasoline UST systems. Soils at the Site consist of fine sands to approximately 10 feet bgs, fine-grained soils ranging from 40 to 50 feet bgs, underlain by sands to 90 feet bgs. Seams and pockets of sand were interspersed throughout the upper fine-grained soil strata, which contained perched, non-contiguous groundwater. The groundwater aquifer was encountered at a depth of approximately 65 feet bgs. Prior activities at the Site included removal of the UST systems, limited contaminated soil excavation and disposal, soil and groundwater contaminant delineation, and installation and operation of a soil vapor extraction (SVE) and sparge system. The site activities were discontinued in June 1995 when MUSTFA funding ceased.
Sagasser & Associates, Inc. conducted an extensive SI at the Site to delineate the existing free product, soil and groundwater contamination in the upper soil strata and water-bearing unit, and the groundwater contamination in the lower aquifer.
Sagasser & Associates, Inc. completed ARA and FFS for acute hazards identified at the Site. Subsequently, Sagasser & Associates, Inc. was contracted to conduct Pilot Testing, Remedial Design, Specifications and Remedial Construction Oversight at the Site for an additional contract amount of $80,627. Prior to conducting pilot testing, Sagasser & Associates, Inc. installed 2 vertical profiling monitor wells to depths on the order of 85 feet bgs. In addition, a 4-inch diameter well was installed for the pilot testing/free product recovery. The well was installed by over-drilling an existing monitor well at the Site that was determined to have a leaking annulus. The pilot testing consisted of a HVDPE aquifer characterization test, a soil vapor extraction (SVE) test on the upper perched groundwater and deep aquifer, an air sparging test on the deep aquifer, an infiltration/aquifer capacity test, and slug tests. Sagasser & Associates, Inc. designed and developed the specifications for construction of the remediation system for the Site. The designed remedial system included air-lift assisted HVDPE in the upper impacted unit and air/bio-sparging in the lower confined aquifer.
The system was bid and constructed and has been in operation for 1 year. The system has effectively eliminated free phase product, decreased source area groundwater impact in the upper groundwater unit and mitigated impact to the lower groundwater unit to levels below Tier 1 RBSLs.
Numerous reports have been prepared for this project including ARA, SI, FFS, Remedial Design, Construction Specifications, Construction Oversight Report, System O&M Oversight, Free Product Monitoring and Quarterly Monitoring Reports.