Integral scientists and engineers provided negotiation, risk assessment, data analysis, and engineering support for the remediation of Greens Bayou, a heavily industrialized urban estuary and tributary to the Houston Ship Channel in Texas. Chemicals of concern were DDT and its degradation products, hexachlorocyclohexane, chlorobenzene, PCBs, PAHs, and arsenic. As the lead consultant for the performing party, Integral was responsible for characterizing the nature and extent of contamination; assessing human and ecological risks; conducting a feasibility study of alternative remediation strategies; performing final design engineering and preparing construction bid documents; providing permitting and litigation support; performing natural resource damage assessment evaluations; and negotiating with state and federal trustees. Integral managed and supported the dredging of approximately 500,000 cubic yards of sediment, including maintenance sediments from the federal navigation channel and contaminated sediment from adjacent areas, at depths up to 26 ft. Sediment was placed in a new 30-acre upland confined disposal facility that was constructed for the project.
Integral successfully completed the engineering and risk assessment tasks on a fast-track basis. The risk assessments led to a significant reduction in the remediation footprint, and substantially narrowed the scope of the NRDA. Results from the post-dredge monitoring program indicated that performance criteria were met within just 18 months after the dredging action, thus no further action was required.Back to List