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Derek Tomlinson

Pharmaceuticals in the Environment (PiE)

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Lead Practitioners Nothing Found

Derek Tomlinson Presenting at Seminar on Pennsylvania Vapor Intrusion Guidance Updates

2026-03-15T10:19:57-06:00November 1st, 2016|Tags: |

Derek Tomlinson (Pennsylvania) will present on "Vapor Intrusion Investigation Best Practices" as part of the Pennsylvania Department of Environmental Protection (PADEP) Vapor Intrusion Guidance Updates, Impacts & Considerations seminar hosted by Alpha Analytical Laboratories at Normandy Farm Hotel & Conference Center in Blue Bell, Pennsylvania on Wednesday, November 9, 2016.

Derek Tomlinson Presents at the American Chemical Society National Meeting

2026-03-15T10:19:49-06:00August 22nd, 2016|Tags: |

Derek Tomlinson (Pennsylvania) will present at the 252nd American Chemical Society (ACS) National Meeting & Exposition entitled "Chemistry of the People, by the People, for the People" at the Loews Philadelphia Hotel in Philadelphia, Pennsylvania at 1:30pm on August 24, 2016.

Webinar Series based on CL:AIRE’s Illustrated Handbook of LNAPL Transport and Fate in the Subsurface Now Available

2026-03-15T10:19:48-06:00August 9th, 2016|Tags: , |

Geosyntec’s Gary Wealthall, Ph.D. (Ontario), and Derek Tomlinson, PE, P.Eng., BCEE (Pennsylvania), contributed to the creation of a series of webinars based on the LNAPL illustrated handbook. The LNAPL illustrated handbook presents best-practice guidance for the assessment and remediation of light non-aqueous phase liquids (LNAPLs) in the subsurface.

Practitioners Promoted to Principal Roles within Geosyntec

2026-03-15T10:19:42-06:00April 28th, 2016|Tags: , , , , , , , , , , , , , |

The Geosyntec family of companies is pleased to announce the promotion of Arthur Forma, Darrell Nicholas, Dave Adilman, Derek Tomlinson, Eric Sager, Eric Suchomel, Helen Dawson, Jeff Ahrens, Kyle LaClair, Marc Leisenring, Mark Johnson, Mike Lambert, Ming Zhu, Rebecca Daprato, and Steve Foster to the position of Principal within the Geosyntec family of companies. Each of these people have made significant contributions to delivering outstanding projects to first-class clients, developing strong relationships with those clients, building our practices, leveraging their own experience and that of their colleagues, recruiting outstanding staff, and working collaboratively with their co-workers. Arthur Forma, P.G., CEG, CHG (California) Arthur's practice includes geologic, hydrogeologic, geotechnical, hazardous waste investigation and remediation, and environmental due diligence. His groundwater investigations, conceptual site models, and remedial action programs have helped clients achieve­ regulatory compliance for sites contaminated with petroleum hydrocarbons, chlorinated solvents, polycyclic aromatic hydrocarbons, metals, pesticides, and perchlorate, even when those sites involve complex hydrostratigraphic terrains. His work in due diligence includes Phase I and Phase II Environmental Site Assessments for real estate transactions at industrial, commercial, agricultural, and residential sites. He helps drive the use of the Electronic Field Data Collection and Reporting "GroundLoggr" tablet app. This app can provide cost savings to clients by reducing manual data entry and by tracking scope automatically. Arthur earned his B.S. in Geosciences from California State University in 2000. Darrell Nicholas, PE (Tennessee) Darrell's practice is focused on the remediation of contaminated sediments with an emphasis on remedial design and remedial action at large sites. He is one of the world's foremost dredging, sediment handling, and dewatering experts, having led the design and management of some of the largest and most complex sediment remediation projects in the world over the past two decades. Applying his problem-solving skills and knowledge of mechanical and hydraulic dredging technology, he has supported clients in the remediation of more than two million cubic yards of contaminated sediments while earning national and international innovation awards. Annually, he is an instructor for the Texas A&M Dredging Short Course, a nationally recognized course for training engineers in sediment management. Darrell earned his B.S. in Civil and Environmental Engineering from Tennessee Technological University in 1978, and his M.S. in Civil Engineering from the University of Kentucky in 1979. David Adilman, P.G. (Massachusetts) Dave's practice is focused on the characterization and remediation of contaminated soil and groundwater, and the design and implementation of large-scale construction dewatering and landfill monitoring programs. A consistent innovator in his practice, Dave has developed advanced techniques and methods to quantify groundwater upwelling into marine environments. His development and implementation of a rigorous methodology and process to quantify the groundwater discharge into the tidally influenced Gowanus Canal is unique in the marketplace. Dave also led an innovative pilot test of the passive use of in situ apatite media for the sequestration of dissolved phase uranium in aerobic groundwater. The results of that pilot test were approved by U.S. EPA for both overburden and bedrock. This is the first application specifically for this purpose in the United States. The uranium sequestration work is also under peer review for Environmental Science and Technology, and will be presented at the Battelle Tenth International Conference on Remediation of Chlorinated and Recalcitrant Compounds in 2016. Dave earned his B.S. in Geology from Miami University in 1981, and his M.A. in Energy and Mineral Resources from the University of Texas in 1986. Derek Tomlinson, PE, P.Eng, BCEE (Pennsylvania) Derek's practice is focused on contaminant hydrogeology with a specialization in sites contaminated with non-aqueous phase liquids (NAPL). He specializes in developing conceptual site models to support the design, implementation, and operation of in situ remediation technologies in porous media and fractured bedrock. Derek assists clients with sites including refineries, terminals, rail yards, waste sites, manufactured gas plants, chemical manufacturing facilities, and other industrial sites in the United States, Australia, Brazil, Canada, and the United Kingdom. He demonstrates Geosyntec's innovation in NAPL remediation through frequent presentations and involvement with professional groups including the Interstate Technology and Regulatory Council (ITRC), ASTM International, the Contaminated Land: Applications In Real Environments (CL:AIRE) remediation body in the United Kingdom, and the United States Department of Defense's (DoD) environmental research programs: the Strategic Environmental Research and Development Program (SERDP) and the Environmental Security Technology Certification Program (ESTCP). Derek earned his B.A.Sc. in Civil Engineering, Environmental and Water Resources Engineering, from the University of Waterloo in 1994, and his M.A.Sc. in Civil Engineering, Environmental, from the University of Waterloo in 1999. Eric Sager, P.G. (Florida) Eric's practice includes site assessment, groundwater monitoring, solid waste management, unit assessments, sampling, RCRA Facility Investigations, Interim Measures, and Long-Term Stewardship for sites contaminated by volatile organic compounds, petroleum hydrocarbons, polychlorinated biphenyls, pesticides, herbicides, metals, and other chemicals of concern in various media. Eric manages some of Florida's largest groundwater investigation and remediation projects including the Soil Interim Measures project at Launch Complex 39B for NASA, and the Brice Lumber project for the Florida Department of Environmental Protection (FDEP). Eric has also managed high-profile NASA site investigations including Mobile Launch Platform rehabilitation sites and the Vehicle Assembly Building, a project involving the collection of over 5,000 groundwater samples. Eric earned his B.S. in Geology from the College of William and Mary in 1994, and his M.S. in Geology at East Carolina University in 1996. Eric Suchomel, Ph.D., PE (California) Eric's practice includes remedial program management; site investigation and characterization; feasibility studies; remedial system design, implementation, and optimization; engineering cost estimates; and litigation support. He specializes in program management and strategy at complex sites, the application of in situ remedial technologies, and the remediation of emerging contaminants, with a focus on 1,2,3-Trichloropropane (TCP). Since 2009, he has been a technical lead and project manager for a series of U.S. Navy-funded studies to evaluate the in situ chemical reduction of TCP by zero-valent zinc (ZVZ). The success of these studies culminated in the first field application of ZVZ for the remediation of TCP. Eric participates in the ITRC, and is the co-chair of the California Groundwater Resources Association (GRA) Events Committee. He is an active presenter at conferences, including the Battelle International Conference on Remediation of Chlorinated and Recalcitrant Compounds, the Association for Environmental Health and Sciences Foundation West Coast Conference, and other local, national, and international conferences. He has published multiple papers on his research, and has written a book chapter on the magnitude of the DNAPL problem. Eric earned his B.S.E. in Chemical Engineering from the University of Iowa in 2001, his M.S. in Environmental Engineering from the Georgia Institute of Technology in 2004, and his Ph.D. in Environmental Engineering from the Georgia Institute of Technology in 2006. Helen Dawson, Ph.D., (Washington, D.C.) Helen's practice spans a wide range of technical disciplines including vapor intrusion; groundwater characterization; and contaminant fate and transport modeling for the spread of DNAPL, chlorinated solvents, and metals. Helen has led a DoD research project for the ESTCP to investigate a new method of vapor intrusion assessment. This leading research is expected to result in technology applicable to many vapor intrusion sites. She has been sought out by the United States Naval Facilities Engineering Command (NAVFAC) to develop fact sheets that will serve as addenda to the Tri-Services Vapor Intrusion Guide. Helen was the primary author of U.S. EPA's Office of Solid Waste Emergency Response (OSWER) Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils. She also was the primary investigator and author on two key technical documents that support vapor intrusion assessment: one on background indoor air concentrations in residences, and another on subsurface-to-indoor air attenuation at vapor intrusion sites. She continues to advance the state of the practice though presentations for clients, talks at national conferences, and participation in expert panels advising regulatory agencies. Helen earned her B.S. in Geology from Stanford University in 1978, her M.S. in Geochemistry from Colorado School of Mines in 1981, and her Ph.D. in Civil and Environmental Engineering from Stanford University in 1992. Jeff Ahrens (North Carolina) Jeff's practice includes environmental site assessments; groundwater, soil, and vapor sampling and monitoring; contaminant delineation; investigation work plans; interim measures work plans; health and safety plans; remedial action plans and remedial system design; evaluation of laboratory data; and litigation support. He is a practice leader in thermal remediation using soil mixing with large-diameter augers, steam, and zero-valent iron. His experience with 1,4-Dioxane and the design and operation of advanced oxidation reactors has been helpful to clients. Jeff has delivered technical presentations at the University of South Florida, Florida Atlantic University, the University of Sheffield, and Clemson University. Jeff earned his B.S. in Integrated Science and Technology with Concentrations in Environmental Science and Biotechnology from James Madison University in 2001, and his M.S. in Environmental Engineering from Michigan Technological University in 2003. Kyle LaClair, PE (Virginia) Kyle's practice is focused on engineering and construction industry services, including site and civil, transportation, traffic, and water resources engineering. A certified Design/Build Institute of America (DBIA) Professional, he is active in the energy sector, providing ancillary civil engineering services to electric utility providers. He has actively promoted process engineering to compliment Geosyntec's existing civil engineering and water resource engineering practices. This approach has led to process engineering helping clients with leachate treatment, wastewater treatment, wastewater plant improvement design, and pump and pipe projects. Furthermore, his expertise in electrical substation stormwater drainage for non-compacted pervious stone used as a non-standard land cover. Dominion has now called on his drainage expertise to represent them with regulators and to provide technical guidance to Dominion staff and other consultants. Kyle earned his B.S. in Civil Engineering from Ohio University in 1999. Marc Leisenring, PE (Oregon) Marc's practice is focused on water resources and urban stormwater projects, including developing municipal stormwater treatment criteria; preparing stormwater best management practices (BMP) monitoring plans and design manuals; modeling urban hydrology, water quality, and BMP performance; conducting stormwater science technical research; and developing and implementing water quality control programs. He has special expertise in the advanced statistical analysis and summary of environmental data. With a clear understanding of hydrology and the pollutant-transport process, he has developed and implemented watershed-scale stormwater planning models and analysis tools for new and existing developments. Marc is a technical leader in Geosyntec's water and natural resources practice, winning applied research projects with the Water Environment Research Foundation (WERF), the National Cooperative Highway Research Program (NCHRP), and the Airport Cooperative Research Program (ACRP). Marc has presented the results of his applied research at professional meetings and national conferences more than ten times in the last three years, and has published articles both in the Conference Proceedings of ASCE's Environmental & Water Resources Institute (EWRI) Congress and in Stormwater Magazine. Marc earned his B.S. in Environmental Resources Engineering from Humboldt State University in 2001, and his M.S. in Civil and Environmental Engineering from Portland State University in 2011. Mark Johnson (Maryland) Mark's practice is focused on site investigation and remediation, groundwater assessment and remediation, subsurface vapor intrusion to indoor air, environmental management assessment and systems, and brownfield redevelopment planning and design. He has led hundreds of transactional due diligence projects, including site assessments, investigations, and remedial actions. Mark provides clients with detailed analyses and cost evaluations of the environmental liabilities at complex industrial, chemical, and refinery facilities in support of litigation, insurance claims, and bankruptcy proceedings. He has expanded our capability to conduct environmental due diligence and compliance projects under state and federal regulations in the United States, and internationally in Canada, Mexico, Costa Rica, and Colombia. Mark earned his B.A. in Geology from Johns Hopkins University in 1995, and his M.S. in Environmental Engineering from the University of Maryland in 2004. Mike Lambert, P.G. (Pennsylvania) Mike's practice includes geology, hydrogeology, numerical and analytical modeling, advanced statistics, litigation support, and contaminated media investigations and remedies for sites under state and federal programs. He specializes in the statistical analysis and interpretation of environmental data, including compliance and detection monitoring, trend analysis, hot-spot analysis, and analytical modeling. Mike has experience in the design, implementation, and interpretation of geophysical surveys for environmental and engineering applications, and groundwater fate and transport models for evaluation of remedial alternatives. Mike has developed new clients for Geosyntec, including West-Ward Pharmaceuticals and Warren Feldman Enterprises. His project delivery excellence has expanded project work for clients including Ingersoll Rand; the Southern Jersey Family Medical Center; Duane Morris; CSX; Somerville Borough, New Jersey; and Ropes & Gray. Currently, Mike manages two of the largest projects in New Jersey: the redevelopment for the Somerville Landfill and the redevelopment of a former Ingersoll Rand site in Phillipsburg. Both of these projects require significant interoffice collaboration, with components performed by staff from our offices in Acton and in Columbia, Maryland. Mike earned his B.S. in Geology and Geophysics from the University of Connecticut in 2002, and his M.S. in Geophysics from Massachusetts Institute of Technology in 2003. Ming Zhu, Ph.D., PE (Georgia) Ming's practice includes geotechnical and geoenvironmental design and analysis; geotechnical instrumentation and monitoring system design and construction; municipal solid waste landfill design and permitting; contaminated site remediation; landfill gas collection and control system design; geotextile tube structures; and geotechnical numerical modeling. Using his experience in geotextile tubes and instrumentation, Ming has collaborated on nine papers and articles published in professional magazines, and has delivered eleven technical presentations at conferences. His efforts have helped expand Geosyntec's technical service capabilities into geotechnical niche areas and have led to projects involving geotechnical instrumentation and geotextile tube structures. Ming earned his B.S. in Hydraulic Engineering from Tsinghua University in 1996, his M.S. in Hydraulic Structural Engineering from Tsinghua University in 2001, and his Ph.D. in Geotechnical Engineering from the University of Michigan in 2005. Rebecca Daprato, Ph.D. (Texas) Rebecca's practice includes contaminant delineation; groundwater, soil and air sampling; membrane interface probe (MIP) logging; data management and analysis; oversight and analysis of 3-D models using Environmental Visualization System (EVS) software; remedial system technology evaluations and design; and remedial system optimization. She specializes in the evaluation and implementation of bioremediation applications for the remediation of soil and groundwater impacted by chlorinated solvents, and the application of molecular techniques to evaluate dechlorination potential and extent. She has co-authored poster and platform presentations for Battelle conferences, was a member of and trainer for the ITRC's Green and Sustainable Remediation team, co-taught a course at Rice University on Environmental Chemistry, and taught a Green and Sustainable Remediation workshop for NASA Real Property Managers. Rebecca earned her B.S. in Chemical Engineering from Florida State University in 1999, her M.S. in Environmental Science and Engineering from Rice University in 2001, and her Ph.D. in Environmental Science and Engineering from Rice University in 2007. Steve Foster, Ph.D. (Colorado) Steve's practice involves developing strategic risk-based solutions for clients to cost-effectively manage risks. This work spans the full lifecycle of the risk assessment process, including developing and reviewing work plans for sampling and analysis, risk calculations, toxicology assessment, data reduction, report preparation, and the integration of risk assessment into remedial strategies. He is the primary author of more than 100 human health and ecological multi-pathway or multi-chemical risk assessments for sites regulated by CERCLA, RCRA, and state-led programs. His air quality practice includes assessing vapor intrusion into homes and offices, and he has provided expert testimony and litigation support on vapor intrusion cases. Steve earned his B.Sc.in Chemistry form the University of Sussex in 1978, his D.I.C. in Chemistry from the Imperial College of Science and Technology in 1980, and his Ph.D. in Organic Chemistry from the Imperial College of Science and Technology in 1981. He was a Post-Doctoral Fellow in Toxicology at the University of Wisconsin in 1984, and a Post-Doctoral Fellow in Cancer Research at Harvard University in 1987.

Derek Tomlinson Co-Instructing Course for ITRC on LNAPL Science, Management and Technology in April

2026-03-15T10:19:35-06:00March 4th, 2016|Tags: |

Derek W. Tomlinson (Pennsylvania), will teach a two-day classroom training course entitled, "Light Nonaqueous-Phase Liquids (LNAPL): Science, Management, and Technology" at the Hilton Atlanta/Marietta Hotel & Conference Center in Atlanta, Georgia on April 5 and 6, 2016.

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.

Hydrogeological Characterization & Modeling

2026-04-29T11:41:56-06:00March 28th, 2014|Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |

Understanding how water interacts with the surface and subsurface environment at any contaminated location is critical to designing innovative and cost-effective remediation systems and site-management strategies. By delineating and understanding the geology and hydrogeology affecting contaminated sites, our experts design strong conceptual site models and groundwater-remediation programs. Ultimately, hydrogeological characterization and modeling affects the performance of any remediation technologies deployed as a solution.

Detection & Culturing of Microbes for Environmental Applications

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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.

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