Bioremediation of PAH-Contaminated Dredged Material at the Jones Island CDF: Materials, Equipment, and Initial Operations

Technical Note DOER-C5

September 1999

Bioremediation of PAH-Contaminated

Dredged Material at the Jones Island CDF:

Materials, Equipment, and Initial Operations

PURPOSE: The U.S. Army Engineer District, Detroit, is currently conducting a bioremediation

demonstration project at the Jones Island confined disposal facility (CDF), Milwaukee, WI.

Dredged material contaminated with polycyclic aromatic hydrocarbons (PAHs) is being bioreme-

diated using composting technology. This technical note describes the materials, equipment, and

initial operations at the Jones Island CDF bioremediation project. The purpose of the Jones Island

bioremediation project is to test the feasibility of using low-cost and relatively passive biotechnology

to reduce PAH concentrations and convert the dredged sediment to material suitable for offsite

beneficial uses.

BACKGROUND: Shipping channels and harbors in the United States require periodic dredging

to maintain depths for commercial navigation. Under current policy guidance contained in "Na-

tional Harbors Program: Dredged Material Management Plan" (21 July 1994), the Corps is

developing management plans to address how dredged material at all harbor projects will be handled

over the next 10 years. Under this program, the Detroit District initiated development of a Dredged

Material Management Plan (DMMP) for the Port of Milwaukee. Initial proposals considered the

construction of a new CDF at a projected cost of $13M. The Port of Milwaukee requested that the

District consider other alternatives in the DMMP, such as reduction of dredging quantities and

beneficial use of dredged material.

Although Corps policy directs that dredged material management planning should consider oppor-

tunities for beneficial use, the alternatives for contaminated dredged material have been extremely

limited. Traditionally, the most cost-effective alternatives for management of dredged material

unsuitable for unrestricted open-water disposal or beneficial use have been capping and disposal in

CDFs - diked structures designed to retain solids. Many Great Lakes CDFs are now nearing or

exceeding design capacity. Of the 26 Federally funded CDFs built in the Great Lakes under PL

91-611, all but two are scheduled to be filled by the Year 2006 (U.S. General Accounting Office

1992).

One criticism of CDFs is that they are not designed nor managed to treat the pollutants placed inside.

Therefore, construction and management of CDFs must consider that they be maintained in

perpetuity, and the adequacy of engineering controls at CDFs is sometimes a source of concern

among Federal and State regulatory agencies, environmental groups, and the public. There is a

need, therefore, to advance CDF technology beyond storage and containment.

Many CDFs were constructed in-water or nearshore, and water captured during construction was

not removed. Initial placement of dredged material was directly into standing water. Most in situ

sediments are anaerobic, and dredged material placed below the saturated zone remains in the

original highly reducing conditions. As CDFs reach design capacity, material emerges from the

water, and aerobic conditions develop in the surface layer as the material dewaters by evaporation.