Union Carbide Corporation
In December of 1993, the primary wastewater treatment system at Union Carbides Seadrift Plant was replaced with new and innovative technology that not only exceeded the regulatory requirements but eliminated an offensive odor as well.
This project is the replacement of two earthen water treatment lagoons with a state-of-the-art, fully enclosed, 5.5 acre wastewater treatment reactor. The new wastewater treatment reactor is double-lined and covered with an anaerobic biological treatment unit used to decompose organic chemicals in the plants wastewater. The base of the impoundment consists of a compacted three foot thick impermeable clay barrier topped with two 60 mil High Density Polyethylene (HDPE) membrane liners. In between the two HDPE liners is a drainage layer which allows any leaks in the top liner to be detected, collected, and removed from the liner system. The installation is 820 feet long by 320 feet wide and has an average depth of approximately 18 feet. The unit holds approximately 25 million gallons of biologically active waste water at normal operating levels.
This design ensures protection of the underlying soil and groundwater by providing multiple barriers between the wastewater and the surrounding environment. The HDPE cover collects and directs the gases produced in the lagoon to an emission control system which treats both the gases and the odors in the water before water is discharged to the polishing ponds. This cover has reduced hydrogen sulfide releases by 95% while improving outfall water quality.
Details of Reductions
Additional Information :
The initial capital cost was $14.5 million with benefits to the environment