Contaminant Reduction and Decontamination

Significant portions of Harbor sediments are contaminated as a result of a complex history of pollution events that have occurred over decades and continue to occur today. Though many agencies have a more direct role in solving this problem, the Comprehensive Conservation and Management Plan (CCMP) and the DMMP Interim Report did identify a potential role for the New York District in the contaminant reduction effort. In addition, decontamination and treatment technologies continue to be investigated, within the Corps, by other agencies, and through private-venture projects.

Contaminant Reduction



Distribution of cadmium in sediment core sample

Contaminated sediments in the berths and waterways of NY/NJ Harbor pose many obstacles to effective dredged material management. A lack of baseline data combined with a limited scientific understanding of the linkages between contaminants, associated species, and the ecosystem make identification of contaminant sources and determinations of effective solutions difficult. These problems are further complicated by the interactive effects of multiple contaminants on multiple species. Given the complexity of the environment and the current state of understanding it is evident that there are no simple solutions or clearly defined pathways for proceeding.

However, many promising programs exist and through the forging of new partnerships to focus efforts and maximize funds, we can improve the technical and political acceptability of new and existing contaminant reduction programs and technologies.

The New York District's Contaminant Reduction Program compliments efforts underway through the Harbor Estuary Program (HEP) to identify pollution sources as a first step in developing an effective control plan. The Corps' efforts focus on building the data sets and data evaluation tools necessary to gain an increased understanding of the spatial distribution of chemical contaminants in the NY/NJ Harbor region. The goal of the data management program is to build a high quality, well documented database containing historical data and incorporating new data sets as they become available through the HEP.

 


Distribution of PCBs in Surfical Sediment

The data maintained in the database will be readily available to researchers, managers and decisions makers. The data evaluation tools are geared for interpreting the variable and complex data sets. Utilizing Geographic Information Systems and spatial interpolation programs the information contained in the data sets can be displayed in informative formats so they can be easily understood by the managers and the public. The success of the contaminant reduction program is contingent on the formation of partnerships with the other federal, state, academic, and not for profit organizations. Currently, the New York District is involved in many such partnerships, including the Sediment Contamination Reduction Work Group (SCRWG). The SCRWG comprises agencies and other entities with responsibilities in implementing the Contaminant Assessment and Reduction Program (CARP).

The CARP includes data collection, chemical analysis, data synthesis, toxics modeling, and decision-making. The New York District is responsible for the database management program of the CARP. Continued participation in work groups in pursuit of common goals is an essential element of the Dredged Material Management Program.


Decontamination


The data maintained in the database will be readily available to researchers, managers and decisions makers. The data evaluation tools are geared for interpreting the variable and complex data sets. Utilizing Geographic Information Systems and spatial interpolation programs the information contained in the data sets can be displayed in informative formats so they can be easily understood by the managers and the public. The success of the contaminant reduction program is contingent on the formation of partnerships with the other federal, state, academic, and not for profit organizations. Currently, the New York District is involved in many such partnerships, including the Sediment Contamination Reduction Work Group (SCRWG). The SCRWG comprises agencies and other entities with responsibilities in implementing the Contaminant Assessment and Reduction Program (CARP).

The CARP includes data collection, chemical analysis, data synthesis, toxics modeling, and decision-making. The New York District is responsible for the database management program of the CARP. Continued participation in work groups in pursuit of common goals is an essential element of the Dredged Material Management Program.

Decontamination works by reducing contaminant concentrations, contaminant mobility, and/or toxicity of contaminated dredged material. This can be achieved by mechanical, chemical, thermal, or biological processes, or any combination thereof.

For the NY/NJ Harbor, the formidable challenge posed for this management approach is to process, in a cost-effective and environmentally protective manner, relatively large volumes of contaminated dredged estuarine sediment. most of this sediment contains a wide range of organic and inorganic contaminants at relatively low concentrations (though several sediment "hot spots" outside navigational areas contain significantly higher contaminant levels).

Dredged material that has undergone treatment may be acceptable for various beneficial uses. If the end product is a soil-like material, it could potentially be used as construction fill, landfill cover, or capping material at brownfields and mining sites. Other technologies may produce construction aggregate, glass products, or cement products.


ECDC's solidification/stabilization operation at Port Newark, NJ for placement in a brownfield in Kearny, NJ

The US Environmental Protection Agency and the US Army Corps of Engineers have been jointly conducting an investigation and demonstration of decontamination technologies applied to contaminated dredged material from the Harbor. The US Dept. of Energy Brookhaven National Laboratory is providing technical support. This federal project has been authorized by Section 405 of the Water Resources Development Act (WRDA) of 1992 and Section 226 of WRDA 1996.

Bench-scale testing of twelve different technologies was completed by 1996. This was conducted in the laboratory using small volumes of sediment (5-10 gallons each) to find out whether the basic chemistry and mechanics of the process works on Harbor sediment.


Pilot demo at Port Newark, NJ on manufactured soil production followed by phytoremediation

Based on the bench-scale results, five of these technologies were selected for pilot-scale testing (up to 20 cubic yards (CY) each).

This was performed in the field using scaled-down but similar equipment as would be used in full-scale operation. The technologies tested were solidification/stabilization, manufactured-soil production/phytoremediation, solvent extraction, plasma-arc vitrification, and a thermo-chemical process using a rotary kiln. Pilot testing was completed by 1997. We are also working with other technology vendors, supplying them with test sediment and evaluating their processes.

We are now planning a production-level demonstration of up to three technologies, each processing at least several thousand CYs. This would be the last demonstration step to help evaluate whether the process is technically and economically feasible for full-scale implementation in the Harbor region. Major activities leading to startup of each demonstration facility include site acquisition, National Environmental Policy Act (NEPA) documentation, permitting, design, and construction. Because it will be difficult to secure sufficient federal funding, public-private partnerships will have to be developed to finance and implement the production-level demonstration.


OENJ Corp.'s solidification/stabilization operation at Elizabeth, NJ

In addition to the technology testing, the federal project includes ancillary studies, such as sediment visualization, treatment-train development, preliminary risk assessment, investigation of beneficial uses, and a public-outreach program.

One decontamination technology, solidification/stabilization, has already found successful commercial application in the Harbor region. Two private-venture projects are underway, mixing contaminated dredged material with portland cement and other binding agents.

OENJ Corp. is using stabilized material for structural fill at a parking lot at the Jersey Gardens Mall Site in Elizabeth, NJ. ECDC Environmental is using stabilized material to cap a brownfield at the Seaboard Site in Kearny, NJ. A demonstration project is planned for the Bark Camp Mine Site near Penfield, PA to stabilize Harbor dredged material with coal fly ash to be used for mine reclamation.

The Port Authority of NY & NJ is currently conducting treatability studies of five technologies whose end products are either construction aggregate or flowable fill. The NJ Office of Maritime Resources will be conducting pilot testing (~1 CY) and production-scale demonstration (>30,000 CY) of decontamination technologies in the coming years. These efforts will be closely coordinated with the federal project.