Some Baltimore Harbor Dredge Sediments Found Suitable for Reuse

Sediments dredged from Baltimore Harbor shipping channels may be suitable for a number of innovative uses, according to a new report. These uses range from construction materials to nonagricultural soil amendments.

The report, Sediment in Baltimore Harbor: Quality and Suitability for Innovative Reuse, results from a year-long review by an independent technical team. Its purpose is to provide the Port of Baltimore, citizen stakeholders, and other interested parties with an objective approach for handling and using sediments from the harbor.

Each year, the Army Corps of Engineers and the Maryland Port Administration oversee the dredging of some 4.5 million cubic yards of sediment. About one third of that sediment — 1.5 million cubic yards — comes from harbor channels inside the Patapsco River. That harbor sediment alone provides enough material to build an 8-foot wide, 4-inch thick driveway from Baltimore to San Francisco — every year.

With increasingly stringent sediment disposal requirements specified by the Dredged Materials Management Act of 2001, the Port of Baltimore faces a number of challenges in dealing with dredged sediment. Prohibitions on open water dumping and the anticipated closure of the Hart Miller Island Dredged Material Containment facility led the Maryland Port Administration to charge an Innovative Reuse Committee with seeking beneficial and innovative alternative uses for appropriate dredged materials. That Committee recommended a neutral technical review by outside experts to determine the suitability of dredged materials from the Harbor as an essential step.

In 2008, the Maryland Port Administration engaged Maryland Sea Grant and the Chesapeake Research Consortium to organize and facilitate a review of the issues surrounding sediment quality in Baltimore Harbor. They in turn tapped top experts from around the country to form an Independent Review Team, reflecting expertise in biogeochemistry, sediment contaminants, regulatory criteria, risk assessment, and port operations.

Jonathan Kramer, the director of Maryland Sea Grant, and Kevin Sellner, the director of the Chesapeake Research Consortium, served as organizers and facilitators of the effort.

The review team's 110-page final report presents a range of observations, findings, and recommendations. Based on a review of available historical data, the team found that sediment taken from locations in currently dredged channels is of sufficient quality for most of the innovative reuse options currently under consideration by the Innovative Reuse Committee. Further feasibility assessments for innovative reuse are therefore clearly warranted.

• Sediment taken from locations in currently dredged channels is of sufficient quality for a variety of innovative reuse options, such as fill for mines and for sand and gravel pits, and components in cement filler and lightweight aggregate materials.
• A limited number of locations meet Maryland criteria for residential reuse, including manufactured topsoil not meant for cropland.
• None of the locations sampled meet the most stringent criteria for unrestricted upland reuse (such as agricultural land amendment).
• Some sediment in locations outside the channels is contaminated to the point that consideration should be given to leaving it in place.

In its report, the team lays out a step-by-step protocol to help determine reuse options available for given dredging projects. This guidance includes application of the team's criteria applied in the context of understanding and minimizing risk. Central to this process, the team recommends that before decisions are made regarding dredging and innovative reuse, any specific location be subject to case-by-case, site-by-site testing, risk assessment, and monitoring.

For additional information, including a downloadable copy of the entire report, as well as a four-page layperson's summary, visit the web at www.mdsg.umd.edu/dredging.

Contacts: Jonathan G. Kramer 301-405-7500, Kevin Sellner 301-261-4500