MGP Dredge Treatment System

GWTT was called to a former manufactured gas plant and petroleum storage facility in Utica, New York to treat groundwater during soil remediation activities and water generated during dredging of contaminated sediments from the nearby harbor. The groundwater treatment system was designed to treat water from excavation dewatering activities at a sustained flow rate of 4,000 GPM and incorporated chemically enhanced precipitation technologies, multi-media filtration units, and a plate-and-frame filter press to reduce the volume of precipitated solids. After constructing the treatment plant, GWTT provided operation and maintenance services 24 hours per day, 7 days per week for a period of three months.

After completing the groundwater treatment project, GWTT immediately shifted gears and provided a 4,000 GPM system to treat water generated by hydraulic dredging of the adjacent harbor. Dredge discharge was directed to a large cofferdam structure wherein GWTT constructed a chemical feed system to add and mix coagulant and anionic polymer. The chemical feed system, an alternative proposed by GWTT to the engineered specification, successfully enhanced solids precipitation in the cofferdam as well as physical filtration of residual solids. GWTT’s physical treatment plant contained 16 high-capacity bag filter vessels piped in parallel and eight 20,000-pound-capacity granular activated carbon adsorbers. The overall treatment system was so effective that harbor dredging was completed in just 8 weeks; our client, a major electric and gas utility, had significant cost savings for completing the project 4 weeks ahead of schedule.