RELATED RESEARCH AND DEVELOPMENT PROGRAMS

ERDC TN-DOER-T2

December 2000

Innovative management solutions for these sediments must include affordable decontamination,

treatment, and beneficial uses of the residual end products.

Treatment is defined as a way of processing CDM with the aim of reducing the amount of

contaminated material or reducing the contamination to meet regulatory standards and criteria.

Treatment techniques are available for different types of contaminants in CDM. Some of these

techniques are still in a demonstration stage, while others are approaching large-pilot scale or

full-scale operations. Because the CDMs may contain various mixtures of heavy metals, petroleum

hydrocarbons, and organochlorine compounds, they present a formidable challenge to treatment or

decontamination technologies. Therefore, significant innovation will be required to develop a

viable treatment or decontamination scheme to solve the problem of CDM in navigation projects.

To address the problem of contaminated sediments in navigation projects worldwide, in 1998,

PIANC Permanent Technical Committee I, Working Group No. 17, published a two-volume report

CD-ROM entitled, "Handling and Treatment of Contaminated Dredged Material (CDM) from Ports

and Inland Waterways" (PIANC 1998). This was the first international document on the

comprehensive management and treatment of CDM from navigation projects.

Chapter 5, Volume 1, of the report covers dredging project requirements. The report summarized

the status of treatment of CDM as follows:

A wide variety of treatment techniques are available for CDM. The currently available

technologies can destroy, remove, or immobilize all types of contaminants and are appli-

cable to almost all types of CDM. The costs of treatment are still high, but are decreasing.

Full-scale separation and dewatering techniques are already being used internationally.

Landfarming, bioslurry treatment, flotation, and gravitational separation are very promis-

ing, lower cost techniques and have been used at full scale at a few sites. Thermal treat-

ment technologies have been used at a number of very highly contaminated sites in North

America with success, but at high costs.

Each dredging project involving CDM is a unique situation that demands a "custom- fit-

ted" solution. For each site, the optimal combination of treatment techniques must be de-

termined by weighing technical, economic, and environmental aspects. As placement

costs continue to rise, treatment of CDM will become more attractive.

RELATED RESEARCH AND DEVELOPMENT PROGRAMS: Sediment treatment has

received much attention in recent years. Several research and demonstration programs are aimed

primarily at the need to develop technologies for handling and treatment of contaminated sediments

from freshwater and marine ecosystems. Programs have been completed in the Netherlands,

Belgium, Germany, Canada, Japan, and the United States (Averett et al. 1990; PIANC 1998; Tetra

Tech and Averett 1994). Two pertinent programs conducted in the United States are briefly

described in the following sections.

Assessment and Remediation of Contaminated Sediments. The 1987 amendments to the

Clean Water Act, particularly Section 118(c)(3), authorized the USEPA Great Lakes National

Program Office (GLNPO) to coordinate and conduct a 5-year study and demonstration project