1. How contaminated is the material being removed? [BACK TO TOP]

Five sediment samples were collected at the site and analyzed to determine the contamination at the site. Samples were taken at five locations at the project site. Generally, the results of four of the samples were similar; the detected parameters and parameter concentrations were consistent. The fifth sample held lower concentrations of detected parameters. The material holds elevated levels of three parameters (PCBs, toxic metals, and SVOCs); as compared to established IDEM standards, the levels of two of the parameters (PCBs, and SVOCs) exceed the standards. The sample results were also compared to the results from other sampling locations in the Grand Calumet River/Indiana Harbor and Canal area. The samples were taken at locations relatively close to the project site. Based on a comparison of the sample results, the material at the project site is cleaner than the material in the GCR/IHC area. Biological and toxicological tests were done to determine the impact of the sediment on benthic organisms. A sediment sample and a control sample were taken, and the tests were done following the guidelines established by USEPA and USACE. Based on the results of the tests and the guidelines, the material is predicted to be toxic to benthic aquatic organisms.

2. What is being done with the dredge material? [BACK TO TOP]

Approximately 3,000 cubic yards (cy) of material will be dredged, dewatered, and disposed of in a commercial landfill.

3. Why can’t all of the material from the GCR/IHC go to a landfill? [BACK TO TOP]

The volume that will be dredged at the East Chicago Sediment Remediation Demonstration Project site is very small compared to the volume at the GCR/IHC sites. The volume at the demonstration project site is 3000 cy; a dredged volume this small can feasibly be transported and disposed of at a commercial landfill. The volume at the Indiana Harbor site is 5 million cy, a volume approximately 2000 times that at the demonstration project site. The logistics and cost of disposing of the GCR/IHC area volume of sediment from the GCR/IHC sites at a commercial landfill are not practical.

4. What technologies are being demonstrated by this project? [BACK TO TOP]

Numerous technologies are being applied at the project site to demonstrate sediment remediation. The technologies at the project site that may be applied at other sites include construction of a barrier to prevent further sediment from entering the channel via the GCR; sediment removal by dredging, dewatering, and disposal; channel and bank restoration to restore and enhance habitat and biodiversity; and post-construction biological monitoring to measure the progress of the restoration measures.

5. What other sediment remediation technologies has the Corps investigated? [BACK TO TOP]

Potential sediment remediation technologies, including those that the Corps has investigated, are in-situ capping, dredging, transport technologies, pre-treatment technologies, treatment technologies, disposal technologies, and residue treatment/management technologies.

6. How is the information from this project to be used by the Corps? [BACK TO TOP]

USACE has authorities for environmental dredging, and follow-on environmental restoration after environmental dredging activities.

7. How might these technologies be applied to the Grand Calumet River cleanup? [BACK TO TOP]

The proposed demonstration project utilizes technologies, most notably the recontamination barrier and the sediment removal activities that can be applied to other sites within the GCR/IHC. Due to the size of the GCR/IHC system, cleanup and remediation activities will be approached in series of reaches. The recontamination barrier will help isolate the reaches that have been dredged and remediated from the areas that contain contaminated sediments.

8. How much does the project cost? [BACK TO TOP]

The project is cost-shared between the federal government, USACE, and the local sponsor, the East Chicago Sanitary District; the cost share percentages break down to 65% federal government and 35% local sponsor. The estimated lump sum for project design and construction is $1.3 million.

9. How long will the project take? [BACK TO TOP]

The construction will span approximately 2-3 years. The monitoring phase will begin after the construction is complete, and will span approximately 3 years. The measures demonstrated at the site can be applied well into the future to other projects at sites within the GCR/IHC.

10. When will it start? [BACK TO TOP]

Phase I Construction, barrier construction and dredging activities, is scheduled to begin March 2004. Phase II Construction, ecosystem restoration activities, is scheduled to begin November 2004. Phase III anticipated to start Spring 2005. Post-construction biological monitoring is scheduled to begin August 2005.

11. Who will do the work? [BACK TO TOP]

Government construction contractors will perform the Phase I construction, the barrier construction and dredging activities. The local sponsor will perform the Phase II construction, the ecosystem restoration activities. Government construction contractors are to perform Phase III construction, plant installation and possibly grading the bank if local sponsor does not perform this task. The local sponsor will also oversee the post construction monitoring.

12. Will there be an opportunity for the public/media to see the demonstration? [BACK TO TOP]

The local sponsor along with the USACE would like to include the public/media in the project as much as possible. There will be construction at the site for an amount of time, and due to the construction activities, there will be security and safety issues at the site. The local sponsor would like to include students in the monitoring activities.

13. What are the characteristics of the clay layer? Will the clay provide the needed stability for the placement of the barrier panels? [BACK TO TOP]

Yes, the clay will provide the needed stability for the placement of the barrier panels. Geotechnical borings were taken at the site to determine the characteristics of the clay at the site. The structural design of the barrier was done based on the geotechnical data and the results of the investigation.

14. Why is the proposed restored fish habitat a cold-water habitat? [BACK TO TOP]

The main reason why the proposed restoration will incorporate a cold-water fish habitat is due to the flow constraints of the project area. The restored effluent channel receives flow from the East Chicago Sanitary District’s sewage treatment plant along with runoff from a CSO discharge basin and near site drainage. The flow rates experienced in the effluent channel are large enough that a slow warm-water system comprised of sands found similar to the Grand Cal system would wash out during high flow events. A system of pools and riffles are proposed in order to stabilize the channel and create fish habitat.

15. Will the effluent flow from the sewage treatment plant cause the substrate to move, impacting the designed system? [BACK TO TOP]

The proposed channel has been designed based on the peak flow rates encountered from the sewage treatment facility and runoff flows. The proposed substrates were selected in order to withstand these peak flow forces; therefore the designed channel will remain stable during all flow conditions.

16. Has the sediment at the site been sampled for physical-chemical parameters? If so, what were the analytical results? [BACK TO TOP]

Yes, the sediment quality at the site has been sampled. The sampling activities determined elevated levels of metals, PAHs, and PCBs, and the concentrations of PAHs and PCBs exceeded the IDEM RISC standards.

17. Will the elevation need to be increased as to achieve the riffles in the proposed channel layout? [BACK TO TOP]

Yes, the elevation of the proposed channel will need to be increased upstream to achieve the necessary hydraulic head for the riffle and pool system to function properly. An analysis of the existing sewage treatment facility layout was done to ensure the proposed altered channel would not adversely effect the capacity of the plant.

18. Is the clay at the project site comparable to the clay in the GCR system; will the proposed demonstration project and technologies that depend on certain clay characteristics at the project site be applicable to other potential sites in the GCR system? [BACK TO TOP]

Yes, the clay at the project site is comparable to the clay in the GCR system, and thus the proposed demonstration project will be applicable at other potential future sites in the GCR system. If clay characteristics differ at potential future sites, the structural designs will be based on the clay characteristics at that site.

19. Is it a new technology or procedure to dredge to the depth of the clay layer? [BACK TO TOP]

The proposed dredge depth is based on environmental considerations, not navigational considerations. The deeper environmental dredge depth is not selected as often because dredging is more often performed for navigational purposes, not environmental remediation.

20. Please explain the purpose and use of the barrier at the potential project sites and reaches in the GCR system. [BACK TO TOP]

Due to the size of the system, the cleanup of the GCR system will be approached in a series of projects, known as reaches. The barrier will be placed to prevent migration of contaminated sediments from one project site that has not been remediated to a project site that has been remediated, thus preventing recontamination.

21· Is the sediment dilatant, i.e. do the sediments resist forces, making the sediments difficult to handle? [BACK TO TOP]

Based on dredging experience and the characteristics of sediment at the site, the sediments are not dilatant and therefore will not be difficult to handle.

22· What are the steps in the sediment removal and disposal process? [BACK TO TOP]

The sediment will be dredged using a mechanical bucket or dragline and dewatered in containers onsite. The pore water from the dewatering process will be pumped to the East Chicago Sanitary District Water Reclamation Facility and treated. The dewatered dredged material will be disposed of at an approved commercial landfill selected by the dredging contractor.

23· What provisions will be made for the downstream part of the channel to mitigate turbid water and migration of sediment and associated contamination? [BACK TO TOP]

During the dredging process, the use of a turbidity curtain just downstream of the sediment barrier will be incorporated in order to reduce the amount of suspended solids released into the Grand Calumet River. Coordination with the Indiana Department of Environmental Management will be done regarding turbidity mitigation.

24· Why is hydraulic dredging not the sediment removal method? [BACK TO TOP]

Hydraulic dredging for the removal of the sediment was considered and deemed unfeasible in the case. The method is not feasible due to the shallow depth of water at the site and small volume of sediment to be dredged. In addition, for this project the cost of hydraulic dredging is greater than the cost of mechanical dredging. Dredging techniques is not one of the demonstration goals identified for this project. Studies on the type dredging techniques would be better suited for a larger project area without depth and access constraints.

25· Is the presentation available on the Internet? [BACK TO TOP]

Yes, click [HERE]