Remediation through Dredging and Bioengineered Containment

Following a break in a discharge pipeline from a hardboard manufacturing plant, 11,500 cubic yards (cy) of effluent solids were released into a backwater slough of the Arkansas River. A beaver dam had entrapped approximately 3,500 cy of the effluent solids and a wetland had emerged from the organically rich solids. The wetlands consisted of diverse, perennial, marsh-type vegetation that offered unique features to the region. The remaining 8,000 cy of solids were in a region of the slough which was covered with water, and due to high biochemical oxygen demand (BOD) of the solids and limited exchange of surface water in this reach, were creating anoxic conditions. Since natural assimilation of the solids did not appear to be proceeding fast enough, it was decided to remove 8,000 cy of solids from this portion of the slough.