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David Bonnett

Hydropower Licensing and Compliance

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To help clients achieve stringent water quality goals, Geosyntec provides rigorous assessment and modeling services to assess the sources and factors that affect the delivery of critical pollutants across watersheds. Through our comprehensive studies and analyses, we provide technically defensible tools and approaches that can be used in the development of Total Maximum Daily Load (TMDL) calculations and watershed protection plans. In addition, we frequently turn to Use Attainability Analyses to examine site-specific water quality criteria that affect attainability goals under natural, human-caused, and economic conditions. Our hydrodynamic and water-quality models integrate inputs from point and nonpoint sources to support our engineers and scientists as they study impacts on water quality in receiving water. These models allow us to understand the assimilative capacities of a given body of water, propose best management practices that can affect pollutant impacts, and predict the time required for a system to recover after being altered. Using watershed studies, water quality monitoring, and hydrological and hydrodynamic modeling, we also can assess compliance with local, state, and federal water quality standards. Using all this information, we are better able to evaluate the magnitude, frequency, and duration of impacts of a wide variety of pollutant sources. Our practitioners offer extensive experience with geographic information system applications for spatial analysis, planimetric and thematic mapping, and data representation. We employ watershed models including the Watershed Characterization System (WCS), Better Assessment Science Integrating Point and Nonpoint Sources (BASINS), and the Watershed Assessment Model (WAMView). We also employ the Water Quality Analysis Simulation Program (WASP), the Environmental Fluid Dynamics Code (EFDC), and the Stream Water Quality Model (QUAL2K) for hydrodynamic and water-quality models. Our practitioners are at the forefront of policy analyses, regulatory compliance, and technology applications that promote sustainable water resources management and ecosystem restoration. We have extensive experience helping local governments develop and negotiate long-term control plans for combined sewer overflows, National Pollutant Discharge Elimination System (NPDES) permits, and consent orders. We also comment on Clean Water Act issues at the state and national level, including the development of new recreational use criteria for water bodies across the county and for the U.S. Environmental Protection Agency's new framework for integrated planning for wastewater and stormwater.

Pharmaceuticals in the Environment (PiE)

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Lead Practitioners Nothing Found

Congratulations to Newly Promoted Senior Principals in 2021

2026-03-15T10:22:39-06:00April 12th, 2021|Tags: , , , , , , , , , , , , |

On behalf of the Leadership Committee (LeadCom) and the Principal Nomination Review Committee (PNRC), I am pleased to announce the promotion of Alex Mckenzie‐Johnson, Amer Hussain, Carrie Pendleton, Dave Bonnett, David Zell, Eric Sager, James Culp, Jamey Dotson, Jim Deitsch, Matt Wissler, Rachel Klinger, Stephen Foster, and Todd Kafka to the position of Senior Principal within the Geosyntec family of companies.

Overview of Waste Management Planning, Engineering & Design

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Geosyntec is a recognized leader in waste containment facility permitting and design. From concept to implementation, we assist our clients in achieving efficient, safe, and secure containment of their regulated wastes that require land disposal. Our practitioners assist our clients in increasing commercial viability, achieving and maintaining compliance, and ensuring that short- and long-term needs are met for new and existing sites and projects. We are experienced in the permitting, design, and construction of expansions and closures of: Municipal solid waste (MSW) landfills Hazardous waste landfills Coal combustion residual landfills Construction and demolition waste landfills Radiological and mixed waste landfills Tailings impoundments Mine waste rock piles and dumps Our waste containment practice specializes in addressing the most complex and challenging projects through our innovative technologies and designs. Our practitioners assist clients with permitting greenfield sites and existing site expansions, maximizing disposal capacity, and solving complex site challenges.   Our practitioners also provide investigation, design, permitting, and construction oversight for on-site disposal facilities for cost-effective, safe on-site disposal of soils, sludges, and miscellaneous debris with a broad range of contaminants, including mercury, PCBs, and volatile and semi-volatile organic compounds.

Overview of Contaminated Site Assessment and Cleanup

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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.

Solid, Industrial, and Hazardous Waste Disposal Facilities

2026-04-21T07:59:21-06:00March 28th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec is a recognized leader in helping our clients achieve safe, secure containment of their regulated wastes requiring land disposal.  We provide engineering and related services for siting, permitting, design, construction management/quality assurance, environmental monitoring, and closure/post-closure care. We are experienced in the design of: Municipal solid waste and construction and demolition debris disposal facilities Coal combustion residuals disposal facilities Industrial waste disposal facilities Hazardous waste disposal facilities The applied research of our leading practitioners for U.S. EPA, DOE, and industry associations has defined the state-of-the-practice for more than 30 years.  As a result, Geosyntec is often first-to-field with emerging technologies related to the secure, safe containment of our nation’s solid, industrial, and hazardous wastes.  Many of the waste containment system design methodologies that we pioneered in the 1980s, 1990s, and 2000s are today the standards of practice in the field. Using experience gained on projects at more than 400 facilities nationwide, we develop practical approaches to design and construction challenges associated with liner and cover systems, leachate and gas management, construction/waste filling/closure sequencing, and geotechnical and earthquake stability. We apply advanced concepts in geotechnical engineering and ground improvement methods to design foundations for sites that have poor structural characteristics or significant geological hazards. We have also pioneered the use of earth retention systems in the design of landfills to maximize airspace volume within limited property boundaries. We are working with our clients to develop approaches for the next generation of integrated waste management practices.  Emerging processes that take advantage of currently available technologies include renewable energy development, enhanced waste separation and processing, enhanced waste degradation through active biological processes, and resource recovery. Integration of conventional and emerging practices is often necessary to meet the complex demands of a community. We work with clients to develop strategic and tactical plans to solve their future MSW management challenges and meet cost, compliance, and service objectives.

Facility Decontamination and Decommissioning

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Geosyntec's engineers and scientists aid many clients in the decommissioning and remediation of power plants, refineries, military facilities, NASA storage and assembly areas, and chemical manufacturing and distribution facilities. We also consult on the remediation and closure of dozens of industrial waste and solid waste containment facilities regulated under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA). Notably, Geosyntec practitioners were key members of the Closure Project Team for the U.S. Department of Energy's (DOE) Fernald Feed Production Center in Ohio, tasked with overseeing the removal of 31 million pounds of processed nuclear product, decontamination and demolition of 223 buildings, and removal of 8,900 cubic yards of radium-bearing waste. For this project, Geosyntec designed a hallmark on-site disposal facility (OSDF) to safely contain low-level radioactive waste and hazardous waste generated during the demolition and site cleanup process. We were selected as the engineer-of-record for the permitting, design, and quality assurance/quality control (QA/QC) services during construction, filling, and closure of the OSDF. The result is a secure 65-acre, eight-cell waste containment facility containing 2.95 million cubic yards of materials and capable of lasting at least 200 years, and up to 1,000 years to the extent achievable with available technology. At Fernald, Geosyntec redefined how modern containment systems could be used to securely dispose of hazardous and low-level radioactive waste. We have since been tasked with the design and construction of new OSDFs at both the DOE's Portsmouth and Paducah Gaseous Diffusion Plants in Ohio and Kentucky, respectively. In addition, Geosyntec engineers and scientists have contributed heavily to asset retirement and conversion services for the electric power industry. For a former waste-to-energy generating facility in Florida, we prepared the preliminary remedial design for a 60-acre site regulated under CERCLA. Our services included construction management, third-party construction quality assurance oversight, and laboratory testing services as well as oversight of the demolition of two incinerators, a 200-foot water tower, and miscellaneous process and administrative buildings. Our optimization of the remedy led to minimized construction costs and approval of design modifications, resulting in client cost savings in excess of $1.5 million. We also provided valuable assistance in negotiating construction claims, which resulted in additional client savings. For another client undergoing a large-scale renovation and expansion of a coal-fired power plant, Geosyntec performed pre-demolition hazardous materials assessments and coordinated the facility's coal handling/processing structure demolition. We subsequently provided implementation design, bidding support, oversight, and documentation of soil remedial action plans, coordinating it with demolition and renovation/expansion activities. By supporting the client and demolition/ construction contractors with time-critical waste profiling, segregation, and management and by acting as regulatory liaison, we helped maintain the project's crucial renovation and expansion schedule. Geosyntec worked with the City of Coral Gables, Florida to prepare the design and bid package for the demolition of a waste-to-energy incinerator and 50-ft tall stack that contained elevated concentrations of lead, arsenic, and dioxins. Our significant experience in the assessment, characterization, and ultimate disposal of incinerator ash helped our client remove the stigma that the site once had in the community and positioned the property for commercial redevelopment. Geosyntec has provided single-sourced services for clients planning to decommission and demolish industrial manufacturing facilities with the intent to obtain regulatory closure in support of the future sale of the property. At these facilities, Geosyntec performed site characterization, decommissioning, decontamination, hazardous building material assessments, oversight of abatement, development of bid documents and bid support, construction management, construction quality assurance, and oversight of scrap/asset recovery. Single-sourced services reduced the clients cost and time to obtain closure by requiring fewer contracts to administer and fewer consultant/contractor interfaces to manage. The coordination of the work is placed with one consultant - Geosyntec. At a former catalyst manufacturing facility in Southern California that produced catalyst for use in petroleum refining, Geosyntec assisted the client in preparing the site for sale as part of their plan for consolidating their manufacturing capabilities into one facility. Geosyntec performed decommissioning and decontaminating support, hazardous building material surveys, oversight of abatement and demolition, Phase I and Phase II site characterization and soil remediation, and obtained regulatory closure.  After Geosyntec completed the work and obtained the regulatory closure, the client sold the property as planned.  Geosyntec has successfully provided similar services to other industrial clients for facilities that include former electrical transformer manufacturing, oil and chemical refining and processing, and aerospace fastener manufacturing. One measure of the value of Geosyntec's services is the repeat business with clients. For example, the client with the catalyst manufacturing facility in Southern California contracted with Geosyntec to perform similar, additional decommissioning and demolition services at their Northern California manufacturing plant.

Natural Resource Monitoring

2026-04-23T13:04:19-06:00March 28th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Geosyntec uses biological assessment and monitoring to create an accurate picture of the affected environment. Our services reliably evaluate the health of streams, rivers, lakes, and ocean environments. In addition, we can offer a less expensive alternative to complex chemical testing programs. Relying on deep experience, our team evaluates the ecological health of a given environment to show how organisms integrate the effects of varied stressors at your site over time. This means Geosyntec can characterize long-term ecological issues and understand the status of highly valued biological communities. By examining a variety of species, their life stages, their survival, and their health, Geosyntec deciphers complex relationships among habitats, bioregions, and ultimately, water and sediment quality. Geosyntec has experienced biologists who efficiently conduct fish and invertebrate collection for both site investigations and NPDES-permit compliance. We also partner with industry-leading laboratories to analyze samples, compile metric scores and data into a project database, and use geographic information system capabilities to define spatial relationships and ensure data consistency and comparability. Geosyntec's biological monitoring services include fish tissue collection for analysis of chemicals of concern; fish population and macroinvertebrate/plankton community studies; fish-kill investigations; and sediment infaunal invertebrate studies. We also conduct habitat inventories and assessments; sediment and water quality toxicity testing; ecological risk assessments; and Natural Resource Damage Assessments. Our practitioners compile environmental impact statements for compliance with National Environmental Policy Act requirements and consult with clients on Clean Water Act (CWA) Section 404 wetland permitting, Section 401 water quality certification, and threatened and endangered species surveys related to the Endangered Species Act (ESA) and Section 7 requirements. For more than a dozen clients, Geosyntec has monitored the concentrations of chemicals found in fish tissue over many years. Often, the fish community is exposed to chemicals via direct or indirect uptake from contaminated sediments. By monitoring the fish tissue concentrations over time, the effectiveness of an environmental remedy can be evaluated. Additionally, biota-sediment accumulation models can be developed and refined to support informed management decisions. This has been used for both active remedies (like dredging) and passive remedies (like MNR). These monitoring data provide our clients and the regulatory agencies with an accurate picture of the affected environment.

Discharge Permitting and Receiving Water Studies

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Geosyntec provides comprehensive water-quality permitting and receiving water-assessment services. Our services include the National Pollutant Discharge Elimination System (NPDES) permitting negotiations and technical support for wastewater and industrial wastewater treatment plant discharges, groundwater discharge, combined sewer overflow systems, and stormwater management. Our water-resources practitioners also specialize in water-quality assessments in large watersheds, rivers, and reservoirs. Many of these projects are multi-year efforts where our services have eliminated unnecessary treatment works, saving clients significant costs. Antidegradation and Water-Quality Reviews Antidegradation and water-quality reviews are essential for permitting wastewater discharge expansions. Regulators use these reviews to determine treatment-system requirements and effluent limitations. Permittees must prepare the review submittals for new or expanded treatment plants. These reviews can range in complexity from basic qualitative evaluations to complex modeling scenarios using actual stream data. Using our thorough understanding of antidegradation and water-quality review processes,we help clients select the most appropriate review approaches when pursuing new or expanded wastewater treatment plants.  Regulators with the US Environmental Protection Agency (USEPA) and state regulators emphasize water-quality-based permitting of municipal, domestic, and industrial wastewater discharges.They do this to address water-quality concerns and attain water-quality standards within receiving streams, rather than basing permits on technology-based limitations that may not adequately protect the specific water resource. Waste-Load Allocation Geosyntec's water-quality-based permitting and waste-load allocation studies may range greatly in complexity, and regulatory involvement and negotiations are critical elements within such projects. Waste-load allocations may be derived using a variety of approaches, and water-quality-based permit limits are derived after determining the most appropriate and defensible waste-load allocation.  Our engineers and scientists use state-of-the-art field monitoring approaches to calibrate water-quality models and establish appropriate water-quality criteria. We have saved our clients several millions of dollars in infrastructure investments by investigating conservative permit assumptions and ensuring a sustainable balance between resource needs and practical budget constraints.

Environmental Impact Studies

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For more than 40 years, strict adherence to guidelines under the National Environmental Policy Act requires all federal agencies to consider the environmental impacts of a broad scope of proposed actions and decisions as well as to consider any reasonable alternatives to those actions. Geosyntec's engineers and scientists offer clients decades of experience in the development of comprehensive environmental impact statements (EIS) for actions requiring federal authorization or that are otherwise subject to federal control. We also prepare EIS as required by regulations at the state and regional level around the country. Our practitioners across multiple disciplines lead the development of EIS for clients within the U.S. Department of Defense, U.S. Customs and Border Protection, the Federal Bureau of Prisons, the U.S. Air Force, and the U.S. Army Corps of Engineers, to name just a few. Impact statements are submitted for public comment periods throughout the development process. In addition, we guide clients through the review and comment by officials with the U.S. Environmental Protection Agency before a final EIS and record of decision can be infused into a program or action. As we develop an EIS, we ensure our detailed analysis provides a discussion of any significant environmental impacts affecting a project as well as the purpose of and need for proposed actions. We then review reasonable alternatives, including a No Action alternative, which would allow agency officials to avoid or minimize adverse impacts or enhance the quality of the human environment. These full disclosure documents detail the process through which a federal project was developed and demonstrates compliance with other applicable environmental laws and executive orders.

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