Sevenson was honored by the Western Dredging Association with the 2019 Excellence Award for work completed on the Zephyr Refinery of the Fire Suppression Ditch. This area is located along the North Branch of the Muskegon River within the Muskegon Lake Area of Concern (AOC), Muskegon, Michigan.

The 2019 WEDA Environmental Excellence Award for Environmental Dredging was presented to the project team from EA Engineering, Science, and Technology Inc., PBC (EA) and Sevenson Environmental Services (SES) for the dredging and restoration of the former Zephyr Refinery: Fire Suppression Ditch Project (Zephyr project).

For more than 40 years the Zephyr Oil Refinery operated with historic releases of petroleum and metals into the Muskegon Lake watershed. These releases contributed to significant contamination of the sediment and wetlands surrounding the site and resulted in beneficial use impairments (BUIs) to the AOC, such as the loss of fish and wildlife habitat. The Zephyr project was identified in the Stage 2 Remedial Action Plan for the Muskegon Lake AOC for restoration in order to support BUI removal. Under the Great Lakes Legacy Act (GLLA), through the strong partnership between the United States Environmental Protection Agency (US EPA) Great Lakes National Program Office (GLNPO) and the Michigan Department of Environmental Quality (MDEQ), the project was completed in late 2018.

The purpose of the project was to dredge the wetlands and ditch to remove contaminated sediment; to clean up lead and total petroleum hydrocarbons; to remove and control invasive species; and to restore wetlands and create a diverse habitat.

At the end of the project, a total of 91.9 million gallons of contaminated water (process and contact water) was treated. All contaminated sediments over a 13.6-acre wetland area with concentrations above 2,000 mg/kg total petroleum hydrocarbons and 128 mg/kg lead to protect benthic organisms and wildlife populations were removed. A total of 49,491 cubic yards of contaminated sediment were dredged from the site, which included 38,272 cubic yards from wetland areas and 11,219 cubic yards from the approximately 1,350-linear-foot ditch portion of the site. Dredging of the ditch required a phased approach for sheet pile installation/removal to stabilize the ditch banks, allowing for dredging in the wet, and providing stabilization for haul roads, which were constructed adjacent to the ditch to allow access along the entirety of the quarter-mile-long ditch and into the wetland areas.

Read the full article here: https://www.dredgemag.com/2019/06/19/weda-honors-environmental-projects/?utm_source=IDR+Master+List&utm_campaign=9638f9901d-EMAIL_CAMPAIGN_1_24_2018_COPY_01&utm_medium=email&utm_term=0_17d3bd0eb9-9638f9901d-26654429