Contaminated sediments have been identified as a significant environmental problem in the Great Lakes and have been linked to the impairment of beneficial uses of Great Lakes waters at every one of the Areas of Concern designated in the Great Lakes Water Quality Agreement. Contaminated sediments have been dredged for environmental remediation at more than 30 Great Lakes sites. At many other sites with contaminated sediments, remediation efforts have become stalled for lack of funding, resources or other reasons (IJC white paper).
Restrictions to navigation dredging is one of the use impairments identified in the Great Lakes Water Quality Agreement. About half of the 4 million cubic yards of sediments dredged annually by the Corps of Engineers from Federal navigation harbors and channels are contaminated. In many cases, environmental remediation of contaminated sediment has been considered or implemented inside or immediately adjacent to Federal navigation channels.
In 1990, Congress provided the Corps of Engineers authority for the removal of contaminated sediments outside the boundaries of Federal navigation channels as part of the operation and maintenance on a navigation project. All environmental dredging actions are to be taken in consultation with the USEPA. This authority was amended in 1996, and several areas identified for priority consideration, including several on the Great Lakes:
- Ashtabula River, Ohio
- Buffalo River, New York
- Grand Calumet River, Indiana
- Saginaw River, Michigan
- Fox River, Wisconsin
The Corps' Buffalo District has been conducting a feasibility study for the Ashtabula River Partnership on alternatives for removal of PCB-contaminated sediments from the Ashtabula River, Ohio (pictured at right). This project is serving as the testing ground for Corps policy on the use of the environmental dredging authority.
The environmental dredging authority requires a cost-sharing partner, who may be a state, local or tribal government. The cost-sharing formula for this authority is condition-specific. If the removal of contaminated sediments outside the Federal navigation channel will reduce future costs for maintenance of the Federal navigation channel, dredging may be conducted at full Federal cost. If not, and the benefits from dredging outside the Federal channel are environmental, dredging (along with transportation and treatment) are cost-shared at 65% Federal and 35% Non-Federal. In all cases, the costs for disposal are cost-shared at 65% Federal and 35% non-Federal.
Congress directed that annual funding for this authority not exceed $20,000,000 Corps-wide. The FY 2000 Appropriations include $600,000 for detailed design of the Ashtabula River environmental dredging project and $100,000 each for reconnaissance studies on environmental dredging at the following sites:
- Detroit River, Michigan
- Muskegon Lake, Michigan
- White Lake, Michigan
- Indiana Harbor, Indiana
- Fox River, Wisconsin.