The web Browser you are currently using is unsupported, and some features of this site may not work as intended. Please update to a modern browser such as Chrome, Firefox or Edge to experience all features Michigan.gov has to offer.
Calumet and Hecla Lake Linden Operations Area Key Investigations
Below is a compilation of key investigation reports for the former Calumet and Hecla Lake Linden Operations Area, known as CHLL. They are very large and highly technical and give a comprehensive approach for assessing potential environmental impacts. Expect long periods of time to view or download.
Compilation and Interpretation of Key Historic Studies - November 2014 |
Final Report, PCB Study Using Semipermeable Membrane Devices in Torch Lake, Houghton County – March 2006 Prepared by the Great Lakes Environmental Center. Semipermeable Membrane Devices (SPMD) are passive samplers that mimic the uptake and bioconcentration of PCBs in fish. This study entailed the collection of data from within Torch Lake and surrounding waters and demonstrated that the surface water in the main basin of Torch Lake contains elevated levels of PCBs. |
Letter Report for Lake Linden Emergency Response – November 2007 Prepared by Weston. In 2007 water levels in Lake Superior reached their lowest levels since the 1920s. The low lake levels in Torch Lake exposed previously unobserved mining era waste deposits including a deposit in the Lake Linden Recreation Area. This report documents the US EPA emergency removal action that was conducted to mitigate the imminent threats to public health, welfare, and the environment posed by the presence of uncontrolled hazardous substances along the shoreline of Torch Lake. |
Summary Report for the Torch Lake Area Assessment – December 2007 (Main portion of the Summary Report which includes Executive Summary through Tables 1 - 14 Figures: Figures 1 - 2a, Figures 2b - 3a, Figures 3b - 4a, Figures 5 - 4b, Figures 5b - 6, Figures 7a - 7b, Figures 8a - 8b, Figures 9a - 9b, Figures 10a - 10c Attachments A - E) Prepared by Weston. At the request of the DEQ (now EGLE), the US EPA evaluated direct-contact hazards associated with exposed stamp sand and the potential presence of other mining-era related waste in industrial buildings, ruins, and land areas proximal to the western shoreline of Torch Lake. At the time of the investigation, the evaluated area included recently exposed shoreline between the edge of the US EPA-installed vegetative cover and the water’s edge as a result of the significantly lower surface-water levels in Lake Superior and its contiguous water bodies. The report provided recommendations for further investigation, maintenance, and or no further action. |
A Sediment Chemistry Survey of Torch Lake – February 2008. Prepared by the DEQ Water Bureau (now EGLE Water Resources division). This Torch Lake sediment investigation was conducted to evaluate a range of contaminants within Torch Lake including previously identified in lake drum disposal areas. The study confirmed the presence of metals contamination throughout Torch Lake, two areas of PCB contaminated sediments, and one potential upland source of PCB contamination. |
PCB Concentrations in Walleye Collected from Torch Lake and Lake Superior - June 2008. Prepared by the DEQ Water Bureau (now EGLE Water Resources division). The goal of this study was to compare concentrations of PCBs in walleye collected from Torch Lake with concentrations in walleye collected from Portage Lake and Huron Bay, Lake Superior to determine if Torch Lake is the source of PCBs in Torch Lake walleye. The study findings indicated that there is a source of PCBs in the Torch Lake watershed contributing to the elevated PCB levels in Torch Lake walleye. |
Groundwater Sampling Investigation Report for Village of Lake Linden, Torch Lake Superfund Site - March 2009. Prepared by the DEQ-RRD (now EGLE Remediation and Redevelopment division), Superfund Section, Geological Support Unit. The objective of this investigation was to further evaluate groundwater exposure pathways in stamp sand deposits along Torch Lake. The study data indicated that contaminants, primarily metals, present in the mining wastes adjacent to Lake Linden are being transported to Torch Lake through shallow groundwater pathways. |
Aroclor Sediment Investigation, Torch Lake Area of Concern – June 2009. Prepared by the US EPA Great Lakes National Program Office (GLNPO). The objective of this study was to evaluate surficial sediments throughout Torch Lake to determine if there are areas of PCB concentrations that might indicate a terrestrial and/or aquatic source of PCBs. The report indicated the presence of a PCB concentrations ranging from 26 to 1,100 micrograms/kilogram. |
Site Inspection (SI) Report for C&H Lake Linden Operations, Lake Linden, Michigan, 49945 - June 2014.(Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8) |
Lake Linden Calumet and Hecla Power Plant Site, Post-Construction Report, Building Demolition and Soil Removal - August 2015. |