Geosyntec applies reliable and innovative approaches to the investigation, evaluation, and remediation of sediment sites to manage their performance and financial, health, and ecological risks. Our practitioners’ expertise and technical skills in sediment assessment and remediation support their efforts to design and implement specialized and efficient solutions to meet our clients’ needs.
We specialize in the assessment and remediation of sites where sediments have been impacted by a wide range of contaminants including metals, crude oil and refined petroleum compounds, polynuclear aromatic hydrocarbons, pesticides, and PCBs. Our conservation, remediation, and restoration experience includes sites ranging from small, intermittent flow streams to large man-made and natural lakes, as well as complex river, estuary, and harbor systems. Geosyntec’s multidisciplinary approach brings together nationally recognized in-house specialists in engineering, ecology and biological sciences, risk assessment and applied toxicology, and earth sciences to address the complex issues associated with contaminated sediment management.
To fully comprehend and address complex sediment challenges, our practitioners employ adaptable treatability studies that provide essential data for sediment management projects to assist our clients and Geosyntec design engineers better understand the physical, chemical, and biological processes that can help mitigate potential risks. These studies are critical for understanding and demonstrating attenuation processes that can occur in sediment if natural conditions are maintained, cap material is placed on top of sediment, or enhancements are added to the sediment or cap material.
Our skills at applying advanced tools benefit our clients in the short term through real-time data generation and adaptive site management. In the long term, clients benefit from a state-of-the-practice understanding of remedy design, implementation alternatives, and an ecological risk assessment approach that looks beyond the conservative, default assumptions.
Advancing the State of the Practice
We are pioneers in sampling, analysis, and data evaluation techniques as a part of the remedial investigations. At the Berry’s Creek Superfund site, we developed new techniques for collecting deep marsh cores and innovative data evaluation processes to quantify risk at this sediment mega-site. At other sediment remediation sites, we creatively solved challenging sediment consolidation and capping scenarios to both meet regulatory requirements and exceed project goals.
Our specialists routinely collaborate with prominent national researchers from academia and government agencies to provide innovative and defensible strategies for sites with contaminated sediments. For example, we collaborated with the U.S. Geological Survey (USGS) to remediate chlorinated solvent-contaminated marsh sediments by applying a bioreactive mat system embedded with a dehalogenating microbial consortium, a technology that Geosyntec helped develop. This project and partnership earned our client recognition as a finalist for the Service to America Medal awarded by the Partnership for Public Service.
Geosyntec has valuable hands-on experience with a variety of advanced assessment tools. We employed one of the first applications of rapid assessment techniques to delineate dense, non-aqueous phase liquids (DNAPL) in Hudson River sediments, which was a technique that allowed the real-time continuous profiling of hydrocarbon DNAPL and measuring of geotechnical properties in sediment to support engineering evaluations and design. At a site in a Louisiana bayou, we used radioisotopes of beryllium and lead to show that at least one inch of sediment had accumulated within the year preceding the survey and that cleaner, accumulating sediments had begun to overlain the site-related contaminants. We have also designed innovative groundwater containment systems and a soil remediation program to prevent the recontamination of waterway and harbor sediments by groundwater or stormwater runoff in busy urban waterways.