Client: Earth Tech, Inc. - MDEQ Project Management Firm
Site Location: 403 North Williams Street (US-131), Mancelona, Michigan
Project Dates: 10/03 - Present

Sagasser & Associates, Inc. was subcontracted by a State of Michigan Contract Management firm to complete a Limited RI, Pilot Study, and Remedial System Design and Construction Oversight of a known contaminated facility. The project has involved identification of potential sources of the known contamination, further delineation of the horizontal and vertical extent of contamination previously identified at the Site, and completion of a soil vapor extraction / air sparging (SVE/AS) pilot study. Data obtained from the Pilot Study was utilized to design an SVE/AS remediation system of which construction is slated to begin in the summer of 2005. Additional activities completed at the Site, based on the identification of additional acute hazards during the Limited RI, included a soil gas survey, indoor air monitoring, and interim abatement of contaminants identified within indoor air of structures located on the Site and adjacent residential property.

The Site consists of a former dry cleaning facility that is currently utilized as an apartment building. The Site has been linked to groundwater impacted with tetrachloroethylene (PCE) identified at the Village of Mancelona Production Well #3 (PW-3) since 1986. The Limited RI completed by Sagasser & Associates, Inc. included vertical aquifer profiling utilizing continuous split-barrel soil sampling methods to depths in excess of 50 feet below the groundwater table. Limited RI activities further incorporated low-stress groundwater sampling techniques completed in accordance with EPA recommended protocol. The RI activities completed by Sagasser & Associates, Inc. identified several acute hazards that included concentrations of PCE in excess of Part 201 Generic Cleanup Criteria and Screening Levels for drinking water (soil and groundwater) and in excess of Part 201 Acceptable Indoor Air Concentrations. Sagasser & Associates, Inc. conducted a Pilot Study at the Site that included vapor recovery (SVE) and injected air (AS) pilot tests utilizing variable vapor extraction and air injection rates. Sagasser & Associates, Inc. evaluated and broke-down data obtained from the Pilot Study to develop a remediation strategy, complete the remediation system design, and develop specifications for construction and O&M of the remediation system.

The remediation system project will include the installation of 21 recovery wells (15 vertical SVE wells and 6 Horizontal SVE wells), 18 sparge points, approximately 950 feet of trenching and associated underground piping, remedial system housing, SVE (2 regenerative blowers) / AS (rotary “claw” compressor) remediation equipment, electrical system and controls, HVAC system, telemetry, Site restoration, system startup and O&M oversight activities. The strategy to be employed for remediation is to complete vapor recovery and air injection in zones to effectively and efficiently abate acute hazards. The project is currently in the Trade Contractor evaluation/recommendation phase.