The St Clair Shores PCB Drain Site is located in St Clair Shores, Michigan. The site encompasses a several block area where polychlorinated biphenyls have been documented to be present in significant quantities in an underground utility corridor. The PCBs constitute a potential threat to the environment. The storm sewer is approximately 15 feet underground. The PCBs are migrating into the storm sewer which empties into two canals connected to Lake St Clair. U.S. EPA conducted a removal of PCBs from sediments in these two canals and cleaned the storm sewer system. At the time of the original cleanup, U.S. EPA assumed the PCBs were from an illegal dump into the sewer system. Subsequent re-contamination of the sewer suggested that a PCB source may be present and causing re-contamination of the areas previously cleaned by U.S. EPA.
In May 2005, U.S. EPA and the Michigan Department of Environmental Quality (MDEQ) conducted a joint investigation to attempt to further define the extent of the contamination and to look for potential source areas of the contamination. As a result of the joint investigation, PCBs were found to be in the sand and gravel backfill surrounding the drain and appeared centered on the area near the intersection of Harper Avenue and Bon Brae Street. Based on data collected from this effort, a report was written on alternatives to address this PCB contamination.
U.S. EPA, MDEQ, and City and County officials have conducted several meetings to discuss the results of the investigation and to discuss actions to mitigate the threat from PCBs to human health and the environment. Due to the depth of the contamination and high costs required to completely remove the contamination from Site, U.S. EPA has proposed placing an impermeable liner in the sewer to trap the PCB contamination in place to allow time for the contamination to be addressed appropriately. The liner is only a temporary protective measure, but it is anticipated to last 10 to 20 years. The PCB contamination can only be completely addressed by conducting a full investigative study of the area and developing a remediation plan to remove the source area and contaminated soils and sediments.
On February 21st, 2006, a meeting of the stakeholders was held to discuss the implementation of U.S. EPA’s planned lining of the sewer
On March 1st, 2006, a public meeting was held in St Clair Shores, MI, from 7pm to 9pm, to inform the public on the work that has been conducted and the planned sewer liner installation. As a result of that meeting, several additional areas were sampled for surface PCB contamination. PCBs were found at the surface greater than the cleanup level established for this site in four additional areas. Those contaminated soils which pose a direct contact threat to human health will be removed in the residential and public access areas.
On May 19th, 2006, a final pre-work stakeholders meeting was held to discuss the implementation of work activities. At this meeting, Macomb County Publics Work officials asked for a plan of the proposed work prior to the installation of the cured in place pipe in the contaminated sewers. The development of a work plan was completed in June 2006 once the subcontractor for that work was awarded the bid and their liner calculations and specifications were approved by the county consultant.
On May 30th, 2006, the main work effort commenced at the site. The work is expected to last approximately 2 months.
• On May 30th USEPA and its contractors mobilized to site.
• On May 31st and June 1st, USEPA and its contractor’s set-up the site and work areas preparation was completed. US EPA and MDEQ met with area residents and discussed the excavation activities which were beginning.
• On June 2nd, 2006, US EPA continued to conduct outreach to the residents and excavation activities were initiated. Based on the levels of PCBs in the surface soils of the dig area, an action level for particulates has been set for activities and will be continuously monitored by the START contractor. MDEQ procured a mobile laboratory, which used immunoassay technology, to screen samples from the excavations today. US EPA also collected samples to be sent to an independent laboratory for analysis. MDEQ also collected 3 samples from residential sump pumps for analysis of PCBs.
• On June 3rd, 2006, excavation and sampling activities continued. Contaminated areas will be excavated to 8 to 12 inches below ground surface (bgs) and then sampled. If PCB contamination remains above the site specific cleanup goal (4 ppm), then the area will be excavated to 2 feet bgs and documentation samples will be collected to determine if any contamination remains. These areas will be backfilled and compacted to eliminate any contact threat to the residents and the data will be recorded for any future cleanup activities determined appropriate.
• On June 4th, 2006, no site work occurred.
• On June 5th, 2006, excavation and sampling continued. A disposal profile sample was submitted to the lab for analysis. A rush (3-5 day) return on data was specified in the bid.
• From June 6th to June 9th, 2006, excavation and sampling continued. US EPA and MDEQ continued to explain the excavation and sampling plan to residents who may be impacted by the activities. Calculations and specifications for the cured in place pipe (CIPP) to be installed in the sewer were delivered to the Macomb County technical consultant contractor. The consultant for the county accepted and agreed with the CIPP specifications for the liner. The manufacturing of the liner material, to take approximately 3 weeks, was initiated. Due to delays in receipt of laboratory data, sample analysis was awarded to a different laboratory.
• On June 10th and 11th, 2006, no site work occurred.
• From June 12th through June 15th, 2006, excavation and sampling continued. The work plan for the CIPP installation and all related activities was delivered to the City of St Clair Shores, Macomb County Public Works, and the Macomb County Road Commission.
• EPA will excavate surface soils contaminated with PCB’s from residential areas and public access areas near Bon Brae Ave., Lakeland Ave. and Harper Ave. in St. Clair Shores, MI.
• EPA will continue to stage the PCB contaminated soil at 19600 Pleasant Road, St. Clair Shores, MI. A staging pad was built in this area to eliminate any risk or run-off or cross-contamination from the staged soil.
• During the sewer cleaning, EPA will dewater and jet-vacuum isolated sections of the sewer prior to commencing CIPP work.
• After the sewer cleaning activities are complete EPA will install CIPP in the sewer. The subcontractor for this work will pre- and post-video the pipe and also conduct all appropriate tests on the installed material.
• Jet Grouting will take place in three pre-determined areas around the sewer pipe to trap the PCB contamination in place. Each area will be grouted to a depth of 30 feet starting from the bottom and extending to the surface.
• Backfill all excavation areas and re-seed.
• Excavation activities will continue at residential and public access areas near Bon Brae, Harper and Lakeland Avenues.
• Install CIPP.
• Document remaining issues once this time-critical removal is complete.
• EPA is excavating surface soil contaminated with PCB only in residential and public access areas.
• PCBs on the property of an operational business were documented by MDEQ. MDEQ has issued the business a Due Care letter to control the contamination.
• US EPA has participated in two television tapings for outreach efforts with the City of St Clair Shores.
• ERRS costs below include awaits for CIPP installation.
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