Project Detail

Environmental Capping of Renard Island

Purpose

The RAP Workgroup recommended closing Renard Island, in the lower Bay of Green Bay to minimize exposure to 2.7M cubic yards of Polychlorinated biphenyls (PCB) and other contaminates contained in sediments placed in the island from the dredging of the Green Bay Harbor.

Objective

Approximately 2,700,000 cubic yards of contaminated sediments have been placed on the island during its operating period. The contaminants of concern are polychlorinated biphenyls (PCBs), mercury and others. These sediments contain PCBs at concentrations generally less than 10 parts-per-million (ppm). Due to a lack of federal funding, the island, although fill to capacity since 1997, has remained unclosed by the USACE, allowing PCB- containing sediment to be in direct contact with the humans, birds and animals. With GLRI funding, Brown County is proposing to complete the environmental capping of Renard Island on its own, without USACE involvement. With GLRI grant funds, Brown County will complete the project more cost-effectively and within the WDNR deadline.

Outcome

Environmentally capping Renard Island will essentially eliminate or significantly reduce exposure to toxic substances, such as PCBs and mercury, currently contained in the island. The health and integrity of wildlife populations and habitat will be protected by the cap from the underlying toxic substances. The continuing availability of dust- containing toxic substances is eliminated by environmentally capping. The uptake of toxic substances by plants and animals will also be eliminated by environmentally capping. Environmentally capping Renard Island will contribute towards restoring lower Green Bay AOC and removing the beneficial reuse impairment. The island and wetlands will provide nesting and brood rearing habitat for waterfowl, shorebirds, and water birds. This project is engineeringly feasible, technically sound, safe, and will provide historic ecological benefits along with navigational benefits. This project has been extensively studied and engineered to ensure project goals and objectives are met. Project performance will be measured by Brown County and public opinion.

Project Type

Great Lakes Restoration Initiative

Project Sub Type

Toxics and Areas of Concern

Project ID

GLRI_00E00499-0

Year Started

2010

Status

Active

Reports and Documents

2011 GLRI Grant-Renard Island Project.doc