Technology Allows Processing of Large Volumes While Retaining Impurities and Making Collection and Disposal Easier.
Environmental remediation projects are often complicated, challenging—and huge. In fact, a number of remediation jobs that should be done have been delayed because there was no economical way of getting them accomplished.
But that could be changing, thanks to a remarkably simple and effective dewatering approach. Geotube dewatering technology is being used in locations around the world to recover and reclaim property that has been contaminated or requires special management
A powerful example is the Fox River cleanup now underway in Wisconsin. For more than 80 years, PCBs have been released from paper mills into the waterways of the area. This area of the Lower Fox River contains the largest concentration of paper mills in the world. A massive remediation project is now underway, one that was 25 years in planning. Geotube® dewatering technology was selected as a core approach for the cleanup.
At the Fox River site, Geotube dewatering technology is part of an operation that involves dredging and dewatering over 750,000 cubic yards of river sediments contaminated with PCBs. Before Geotube dewateirng technology was selected, eleven separate tests were conducted with five different types of river sediments varying in organic content. The project involves more than 75,000 linear feet of 80-foot circumference Geotube containers.
PCB-contaminated sediment is being dredged, circulated through Geotube containers for dewatering, and taken to a permanent landfill for final disposal. Some of the material is so contaminated that it has to be taken to an out-of-state facility for disposal. The process is in full public display; in fact, one of the dredging and dewatering facilities is located just off a major highway and has an 'overlook' area where citizens can stand and watch the operation in action.
The project also calls for monitored natural recovery for Green Bay. This technique relies on natural processes to break down, bury, or dilute the PCBs. In some areas where PCB contamination is deep, the first few feet of sediment may be dredged and dewatered, and then a sand cap placed on top of the remaining material to 'bury' it and prevent it from causing contamination of the water.
'One value of Geotube dewatering technology is that it works on both large and small-scale projects, with the same effectiveness,' said Tom Stephens, Vice President of Business Development for TenCate, manufacturer of Geotube dewatering technology. 'You can operate a system with a single Geotube container, or with dozens, and you can expect consistent results. There is no complicated machinery, and solids are left in a very manageable form.'