Containment facility design: A comparison study of predicted versus actual results at Liverpool, Nova Scotia.

摘要

Dredged material contamination combined with increased regulation of ocean disposal of dredged material has led to increased use of confined disposal of this material. The Confined Disposal Facility for dredged material is designed to address contamination concerns, effluent quality at discharge, and long term management plans. The US Army Corps of Engineers, (USACE), have developed design procedures for the CDF which are used throughout North America.; A shorefront Confined Disposal Facility was constructed as part of a capital dredging project in Liverpool, Nova Scotia in 1993. The design was based on the USACE design procedures. Evaluation during dredging and post dredging time periods has suggested variations in the predicted performance versus the actual.; A review of the design parameters, including geotechnical data, settlement characteristics, effluent characteristics, is undertaken. A discussion of the variations of predicted versus actual performance, including influencing factors, is included. Test results for laboratory testing of post dredge sediment samples are presented and discussed.; A literature review has been completed. Articles relating to the USACE design procedures, field conditions and other confined disposal facility design options have been reviewed.; Recommendations and conclusions include use of representative geotechnical samples at the design stage, re-evaluation of the design if proposed equipment at the contract stage varies from that used in design, and use of a modified consolidation test. Continued evaluation of field performance of confined disposal facilities designed using the USACE design procedures, as reported in the reviewed literature, indicates agreement with field conditions through use of efficiency factors can be achieved.