Chassell Mercury Spill; Portage Lake, Chassell, MI

Portage Lake, Chassell, MI | 2012-Jul-09

Initial Notification: Adapted from EPA OSC report: "On Monday, July 2, 2012, Michigan DEQ requested EPA assistance at a waterfront property on Portage Canal of Lake Superior in Chassell, Michigan. Two metal flasks suspected to contain mercury were found by swimmers in the Lake approximately 30 feet offshore. The swimmers carried the flasks to the dock at their private residence. The Western Upper Peninsula Health Department (WUPHD) confirmed the presence of mercury in the containers. One container was sealed, but the seal was broken on the second container, resulting in mercury being spilled onto the sandy lakebed as the container was carried to the dock. The resident attempted to recover spilled material visible in the shallow water. The Health Department determined the mercury contamination was limited to the dock area. OSC <redacted> and <redacted> of MDEQ arrived at the Site late afternoon on July 2, 2012. Due to the prediction of potential thunderstorms in the area overnight, the containers on the dock were overpacked in a plastic sealable tote. The overpack was not relocated in order to minimize potential cross contamination. EPA and its START and ERRS contractors returned to the Site on July 3, 2012 to conduct an emergency removal action. The contaminated dock area was cleaned to prevent further contamination of the residential property, the gross mercury contamination was removed from the lakebed, the area where the flasks were found was poled to determine if additional containers remain buried in the area, and the mercury waste was removed from the Site. Sediment samples were collected to assess the impact of the spill on the lakebed and determine the need and extent of additional removal activities. USCG and the WUPHD representatives were on-scene during the July 3, 2012 removal activities. MDEQ returned to the Site after EPA, USCG, and WUPHD had demobilized to collect surface water samples. EPA is planning to remobilize to the Site the week of July 9, 2012 to establish an exclusionary zone around the impacted area and conduct a comprehensive site assessment of the spill area. MDEQ, USCG, and WUPHD are expected to also be on site the week of July 9, 2012. EPA is acting as the lead agency for this response." EPA OSC contact the NOAA SSC on July 9, 2012 seeking information on the expected trajectory/migration of mercury on the lakebed. NRC notification #: 1016492