Canal do Fundão Contaminated Sediments GDT Analysis versus Actual Full Scale Project Results

Canal do Fundão is an artificial estuary created in 1951 when the Brazilian federal oil company (Petrobrás) conducted a land formation project adjacent to the eastern shore of Guanabara Bay in the state of Rio de Janeiro, Brazil. In the years since its formation, several "favelas" (ghettos) evolved near the shoreline of Canal do Fundão and raw sewage began to collect in the canal rather than disperse into Guanabara Bay. The estuary was identified as a major environmental concern impacting health and life. In 2004, the federal government of Brazil funded an engineering investigation to define the restoration of Canal do Fundão. In 2007 and 2008, soil borings and samples were taken from the contaminated areas for analysis. Polymer bench tests via the TenCate Rapid Dewatering Test (RDT) were conducted along with the TenCate Cone Test to qualify polymer type and optimum dosage for acceptable performance. Following these tests, a number of TenCate Geotube Dewatering Tests (GDT's) were conducted to validate the polymer selection and dosage, and to predict the full scale project results and final dewatered solids inside the Geotube® containers. The purpose of this paper will be to detail all of the sample testing, types of analysis and how accurately the TenCate GDT tests predicted the actual project results.