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Evan Cox

Pilot Demonstration of In Situ Alkaline Hydrolysis of Organophosphorus Pesticides in Denmark

2026-04-02T15:02:17-06:00February 23rd, 2016|Tags: , , , , , , |

The Høfde 42 pesticide waste disposal site is recognized as the most toxic contaminated site in Denmark. Between 1953 and 1962, the agrichemical manufacturing company Cheminova, with approval of Danish authorities, disposed of hundreds of tons of organophosphorus pesticide (OPP) and pesticide manufacturing wastes in pits at this site, which is located at a beach adjacent to the North Sea. A remedial feasibility study completed by the Danish government determined that in situ alkaline hydrolysis (ISAH) is the most cost effective technology for remediating groundwater and the residual wastes at the site. The Danish government, with funding by the European Union Life Program, selected the team of Geosyntec, COWI A/S, Tufts University, Nasus Water, and the University of Aalborg to conduct three pilot tests to compare three techniques for optimizing pesticide treatment by ISAH: 1) groundwater recirculation; 2) surfactant-enhanced flushing; and 3) acoustic vibration. In all three, tests a primary challenge is to inject strong base [caustic, or sodium hydroxide (NaOH)] to the in situ treatment zone while minimizing exposure of site workers to NaOH and pesticides.

Chlorinated Solvent DNAPL Bioremediation Pilot Test Demonstration in Denmark

2026-04-02T15:02:16-06:00February 23rd, 2016|Tags: , , , , , , |

Groundwater supplies beneath the Kærgård Plantage pharmaceutical waste disposal site in Denmark are contaminated with substantial quantities of chlorinated solvents (primarily tetrachloroethene, or PCE), which are present in the subsurface as dense non-aqueous phase liquids (DNAPLs). Contaminated groundwater from the site discharges to the nearby North Sea, creating a potential human health and ecological risk at a beach adjacent to the site. Since 2004, Geosyntec Consultants has advised the Danish government regarding the remedial strategy for cleaning up the site and mitigating risks at the beach. At Geosyntec’s recommendation, the Danish authorities retained a team of consultants with a goal of evaluating the feasibility of three technologies for remediating the primary DNAPL source areas at the site: in situ biological enhanced reductive dechlorination (ERD), in situ chemical oxidation with Fenton’s reagent, and in situ thermal remedial via steam flushing.

Remedial Delineation and Feasibility Studies for a Manufacturing Site in Dublin

2026-04-02T15:02:13-06:00February 23rd, 2016|Tags: , , , , , , |

Geosyntec Consultants (Geosyntec) Ireland office (formerly Ford Consulting Group) has been retained by this client who has been required under IPPC to address contaminated soil and groundwater issues at their manufacturing site in Ireland. The project objectives have migrated from providing peer review to leading a detailed site characterization study and risk assessment in addition to performing laboratory and field based remedial trials. These are anticipated to lead to full-scale corrective action over a two year period.

Evaluating Functional Stability and Completion of Landfill Aftercare in France, Italy, and the UK

2026-04-02T15:02:13-06:00February 23rd, 2016|Tags: , , , , |

Optimizing and completing post-closure care (PCC), or aftercare, of closed MSW landfills in Europe is a major issue facing SITA, the waste services arm of Suez Environnement. Working with the French Agency for the Environment and Energy (ADEME), Suez and SITA turned to Geosyntec to investigate application of the performance-based Evaluation of Post-Closure Care (EPCC) Methodology in Europe. The EPCC Methodology was developed by Geosyntec to evaluate optimizing and ending PCC at MSW landfills regulated under RCRA Subtitle D in the U.S. Procedurally, the methodology is based on assessment that a closed landfill that no longer represents a threat to human health and the environment. Assessing landfill monitoring and management requirements in terms of maintaining functional stability allows care activities to be progressively reduced until no active care is necessary and only de minimus custodial care activities remain for passive control systems (mainly for the cover).

Site Investigation of a Closed Manufacturing Facility in France

2026-04-02T15:12:02-06:00February 2nd, 2016|Tags: , , , , , , |

An appliance controls manufacturing facility in Thyez, France was active in industrial activities from the 1960s until 2007. Operations at the facility included metal working, painting, assembly, and the production of control devices for household appliances. The current facility owner retained Geosyntec shortly thereafter to complete site assessment activities to prepare the property for potential sale.

Specialized In Situ Treatment Technologies

2026-09-22T12:43:54-06:00February 12th, 2015|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec is an industry leader in remediating difficult-to-treat environmental impacts to soil, groundwater, and sediments through the use of specialized in situ techniques. Our practitioners are adept at expediting site investigations, optimizing remediation solutions, and accelerating site closure through a wide range of innovative technology applications. Our expertise in the implementation of new, emerging, and conventional technologies allows our practitioners to frequently bridge the gap between the development and first-to-field stages of environmental solutions. Our expertise and industry leadership in the advanced application of microbiology-based solutions for the remediation of recalcitrant contaminants in soil and groundwater has established Geosyntec’s solutions as the preferred method, especially for sites with proven resistant to conventional remediation technologies or when compared to the comparatively high costs for the application of physical and chemical technologies that achieve similar results. Two of Geosyntec’s affiliated companies provide specialized services and technologies regarding in situ treatments:

Groundwater Assessment and Remediation

2026-06-30T09:11:21-06:00February 11th, 2015|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec’s expertise in efficient site characterization, including sites that exhibit complex groundwater-flow regimes, has distinguished our firm as a leader in groundwater assessment and groundwater remediation. Our practitioners address a broad suite of contaminants, including metals, chlorinated organic chemicals, petroleum hydrocarbons, and emerging contaminants, and use award-winning, technology-based remediation strategies that are often first-to-field. Many of our hydrogeologists specialize in modeling the fate and transport of contaminants through the most difficult types of media, including fractured and karst bedrock.

Overview of Contaminated Site Assessment and Cleanup

2026-08-18T14:34:36-06:00November 12th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec practitioners rank among the world's top professionals in providing site assessment and remediation services at a wide range of impacted sites using innovative technologies and solutions that consistently advance the state of the practice. Through our use of innovative technologies and solutions, we provide our public and private sector clients with a wide array of services to address their toughest challenges. Our contaminated site practitioners guide our clients through a specialized remediation plan, consult on regulatory strategies, and develop a comprehensive cleanup approach. We can address numerous types of media, including contaminated soils, sediments, and groundwater. Advancing the State of the Practice Geosyntec's practitioners are pioneers in site assessment and remediation. Our senior practitioners have developed and authored guidance material and courses for local, state, and national agencies and associations on remediation techniques and technologies. Working with the Interstate Technical Regulatory Council, Geosyntec practitioners taught a training course on vapor intrusion, including mitigation options for the development of vapor-impacted brownfield sites. Geosyntec practitioners also wrote the guidance document on evaluating, optimizing, or ending post-closure care at impacted sites, including brownfield sites, and developed a patented approach for sub-slab vapor migration mitigation allowing residential, commercial, and industrial development on sites impacted by vapor intrusion. 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 United States Geological Survey (USGS) to remediate chlorinated solvent-contaminated marsh sediments by applying a bioreactive mat system embedded with a dehalogenating microbial consortium, a technology 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. Through a collaborative research project with the University of Florida, Geosyntec professionals helped develop the FLUCL software package for the Florida Department of Environmental Protection. This software is used to calculate exposure point concentration statistics in risk assessment and was the first of its kind to contain algorithms for censored datasets. FLUCL has received endorsements from several United States Environmental Protection Agency regions and the California Environmental Protection Agency. Geosyntec scientists also pioneered the use of genetic molecular tools to characterize microbes in environmental media and are engaged in applied research and development with top academic institutions around the world, including the University of Toronto, Cornell University, and the Georgia Institute of Technology.

Detection & Culturing of Microbes for Environmental Applications

2026-04-29T11:39:16-06:00March 28th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec is a reliable partner for creative, cost-effective and successful bioremediation solutions because we approach remediation with an environmental management perspective. For each client, we develop a clear understanding of how to achieve best-value outcomes using the most appropriate technologies and environmental management strategies for each project. Bioremediation harnesses the natural characteristics and abilities of microbes to clean contaminated soil and groundwater. Our skilled practitioners use a wide array of methods to stimulate the growth of certain microbes that use contaminants as a source of food and energy. Contaminants treated using bioremediation can include oil and other petroleum products, solvents, and pesticides. Geosyntec scientists pioneered the use of bioaugmentation to profoundly refashion in situ biodegradation processes in soil and groundwater. In addition, our scientists remain active in applied research and development with U.S. Department of Defense remediation programs, NASA, the University of Toronto, Cornell University, the Georgia Institute of Technology, and other strategic partners examining future applications and enhancements to bioremediation techniques. Our practitioners also are engaged in ongoing research that examines remedial solutions that tap into the power of metals biogeochemistry and chemical oxidation as well as new techniques for wastewater treatment, vapor intrusion mitigation, and the treatment of energetic, chlorinated, and recalcitrant compounds and dense nonaqueous phase liquids, or DNAPLs. Through our environmental technology research and testing laboratory, SiREM, Geosyntec also provides the tools environmental professionals need to optimize the remediation of chlorinated solvents and other recalcitrant chemicals. As an industry leader, SiREM provides unparalleled technical support combined with a unique range of products and testing services that save our clients money, increases remediation effectiveness, and provide peace of mind during their field implementation of bioremediation solutions. Two of our leading bioaugmentation cultures, KB-1® and KB-1® Plus, have been used for well over a decade to enhance bioremediation of chlorinated solvents at impacted sites throughout the world. These cultures introduce beneficial microorganisms to remedial sites where they are absent or at low concentrations.

Environmental Forensic Studies

2026-04-23T10:12:07-06:00March 28th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , |

Drawing on decades of experience in chemistry, biochemistry, ecology, and biology, our engineers and scientists conduct field and laboratory investigations to identify or characterize biological and chemical challenges impacting soil, sediment, groundwater, surface water, and waste.

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