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Elaina Modlin

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.

Air Dispersion Modeling

2026-04-21T09:58:39-06:00March 28th, 2014|Tags: , , , , , , , , , , , , |

Under many jurisdictions, facility owners are required to evaluate potential offsite air quality impacts to gain regulatory approvals. Our clients need consultants with experience running air dispersion models. These models use mathematical algorithms to characterize atmospheric processes, to understand how pollutants disperse, and to predict ambient concentrations of air contaminants. Geosyntec applies models to demonstrate compliance with allowable ground-level concentrations established by regulatory agencies. We have experience applying various air dispersion models ranging from those that predict ground-level concentrations from continuous emission sources to consequence analysis models used to assess impacts from unplanned catastrophic events. We use air dispersion modeling to assist clients with regulatory and nonregulatory air modeling projects, including permit applications to address ambient air quality and air toxic requirements. Our team works closely with clients to assess plant layout and stack location configurations to avoid negative impacts on the regional airshed and local communities. In addition, our practitioners conduct modeling to evaluate potential offsite impacts associated with risk assessments and hazard analyses. Our modelers are experienced with AERMOD/AERSURFACE/AERSCREEN/SCREEN3, CALPUFF, ALOHA, SLAB and Computational Fluid Dynamics (CFD) models. Our advanced collection and measurement methods help us generate robust data for air dispersion models that describe the complex behavior of pollutants in the air and how they interact with their environment. Our air dispersion modeling experience includes emerging pollutants such as ethylene oxide (C2H4O) and PFAS. Armed with this data, our engineers and scientists can accurately assess how a source affects a particular area and consult with clients on developing comprehensive environmental management strategies.

Hazardous Air Pollutant Control Program Development and Implementation

2026-06-30T12:03:42-06:00March 28th, 2014|Tags: , , , , , , , , , , , , |

Geosyntec helps clients determine performance and the cost of air pollution control techniques. These techniques are designed to reduce or eliminate emissions of hazardous air pollutants (HAPs) and regulated air toxics from industrial and commercial sources. Our air practitioners offer decades of experience measuring and mitigating adverse environmental and health effects caused by HAPs regulated under the Clean Air Act, the Resource Conservation and Recovery Act, and the Toxic Substances Control Act in the United States. We address client challenges at major and area sources across the country involving air toxics such as benzene, perchloroethylene, methylene chloride, ethylene oxide, and per- and polyfluoroalkyl substances (PFAS). Geosyntec's scientists and engineers employ advanced solutions to identify emission stream characteristics from sources located at a variety of industries. We assist clients with selection and implementation of the best mitigation and control systems for their facilities, and we provide permitting assistance under federal, state, and local air construction and operating permit programs. Geosyntec practitioners specialize in process design and air pollution control technology design that helps us develop strategic approaches to complex, multipollutant emission issues. Our process engineering and air pollution control experts provide clients with a balanced approach to their plant operations.

Air Pollution Control Evaluations and Performance Assessments

2026-06-30T11:58:58-06:00March 28th, 2014|Tags: , , , , , , , , , , |

Geosyntec's air quality clients need services for emission control, device conceptual design and selection, feasibility, monitoring, evaluation, and optimization for their facilities. We help clients evaluate emission controls under complex regulatory and operational conditions, and we advise them about how to meet emission standards. We also work closely with clients on the selection of air pollution control technologies that minimize operational costs while still meeting the stringent control efficiencies required by federal and local regulations. Selection of optimal control technology includes consideration of the potential for the generation and removal of secondary pollutants such as combustion by-products, reactive compounds, greenhouse gas emissions, or waste or wastewater streams. With expertise in process design, as well as air pollution control technology design, Geosyntec’s engineers develop strategic approaches to complex, multipollutant emission challenges. These challenges are brought about by evolving emission standards on existing equipment and operations, new capital project expansions, facilities, and emission sources. Our portfolio includes finding ways to control gaseous pollutants using methods including scrubbing, adsorption, condensation, catalytic reduction, and oxidation. We also address combustion management and best operating practices for boilers, thermal oxidizers, engines, and combustion devices. In addition, we design particulate filtration, precipitation, and collection systems, dust control approaches, and other ways to control toxic air contaminants. We measure control system performance by applying standard emission measurement protocols, United States Environmental Protection Agency (USEPA) test methods, and other acceptable evolving measurement science to determine compliance or reduction potential for common criteria air pollutants. Our work often addresses emissions of volatile organic compounds (VOC), nitrogen oxides (NOx), carbon monoxide (CO), sulfur dioxide (SO2), and particulate matter, as well as toxic air contaminants and dangerous compounds like mercury and sulfur trioxide (SO3). Geosyntec installs state-of-the-practice hardware and software that uses cross-duct laser technology to continuously monitor ammonia (NH3) and SO3. We help clients select continuous emission monitoring system (CEMS) and programs for CEM compliance with federal state and consent decree monitoring provisions. Additionally, we prepare CEM data quality assurance and quality.

Waste Management and Minimization Services

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Municipal and private clients turn to Geosyntec to solve complex problems involving a wide array of solid waste management issues. We guide clients through the technical, regulatory, and public relations aspects of municipal solid waste, construction and demolition waste, nonhazardous industrial solid waste, hazardous waste, and other waste classes. Because Geosyntec’s waste management professionals span disciplines, from geologists and engineers to environmental management, due diligence consultants, and environmental, social, and governance (ESG) professionals, we offer solid waste clients a comprehensive understanding of their systems and a full suite of services to address their challenges. Recognized as leaders in their fields, our team has worked with clients on more than 2,000 landfill, environmental, and geotechnical projects throughout the United States over the last three decades. From siting and permitting to closure construction, clean closure, and post-closure monitoring and care, we address the complete life cycle of a project. We also offer waste mining consulting services to help our clients redevelop former waste management facilities. Because our clients are increasingly driven to improve performance, minimize waste, secure value for money, achieve required returns, and optimize the use of assets, we equip them with a deep understanding of market drivers and operational issues. Our advisory specialists translate technical and commercial issues into financial analyses, valuations, and support for financial models, with clear recommendations made for our clients’ benefit, without bias to a particular vendor, service, or product. Our services include the following: Design, permitting, construction, maintenance, decommissioning, and closure of transfer stations, materials recovery facilities, convenience centers, waste-to-energy plants, surface impoundments, and landfills Groundwater, leachate, and landfill gas management Waste minimization and diversion, including recycling programs and organics collection Carbon credits and ESG issues Financial modeling and cost/benefit analyses Waste flow analysis, composition, and generation studies Regulatory compliance Economic liability and long-term environmental liability evaluation and management Strategic planning

Air Quality Permitting and Compliance

2026-06-30T12:01:26-06:00March 27th, 2014|Tags: , , , , , , , , , , , , , , |

Government regulations are constantly evolving. Air quality and emission standards require companies to plan for and demonstrate ongoing compliance with monitoring, testing, emissions control, recordkeeping, and reporting requirements. Companies need solutions to reach compliance while minimizing operational and financial impacts. Geosyntec has extensive experience with the critical path items that need to be managed throughout the process. This includes characterizing emissions from new or modified equipment, identifying the correct permitting strategy, defining the regulatory requirements, and completing ambient air quality impact analyses of air contaminants released from process equipment. Geosyntec’s services are designed for long-term success. We help clients explain project benefits and environmental impacts to interested stakeholders. In addition, we review draft permits or licenses to maximize operational flexibility and to minimize ongoing compliance demonstration burdens. Our understanding of laws and regulations pertaining to air quality helps us create permitting strategies for clients. Our strategies provide clients with innovative and best-value solutions for their air quality permitting and compliance challenges. Air Permitting:  Unique solutions that often result in avoiding major source permitting requirements Permitting assistance to our clients under federal, state, and local air construction and operation permits, with a record in crafting strategic approaches to air quality challenges Air Compliance and Reporting: Effective and efficient compliance solutions for our clients so they can address reporting challenges and remain in compliance Staff with expertise in regulatory interpretation to save clients time and money At Geosyntec, we provide clients with "fit for purpose" solutions that are practical to implement. With an eye to resource efficiency and timely results, we help our clients get the project done right the first time. Geosyntec practitioners frequently collaborate with colleagues at the United States Environmental Protection Agency (USEPA), the US Department of Energy (DOE), the Electric Power Research Institute (EPRI), the Air and Waste Management Association (AWMA), trade groups, and other organizations to develop or interpret new air pollution regulations, permitting, and control strategies. Through novel research, our experts develop unique and innovative permitting strategies and methods to demonstrate air quality compliance with complex permitting requirements.

Management Systems Services

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Whether it's due to customer, shareholder, or regulator-requirements, transitional workforce challenges, or some other reason, organizations are seeking to develop, implement, maintain, and improve upon their systems for environmental, safety and health, and sustainability management. Limited resources and management system expertise within the organizations can be a road block. Geosyntec's comprehensive understanding of our clients' operations paired with our expertise in management system development and implementation allow us to provide our clients with innovative and cost-effective solutions for identifying, prioritizing, and managing more efficiently the environmental, safety and health, and sustainability risks and opportunities associated with their operations. Our management system experts offer clients a broad array of services, including policy development support, system element gap analysis, document and training material development, performance monitoring data analysis, trending, and visualization, information management system design and optimization, system auditing, nonconformance correction planning including root cause analysis, and management review and third-party certification preparation. Our projects routinely involve organizations with multiple and varied facilities, multi-cultural stakeholders, and transient workforces. Through our work, Geosyntec's clients improve performance and achieve their operational goals. Geosyntec's management system implementation programs are tailored to meet the needs of each client resulting in a smooth integration and minimized operational disruption. Geosyntec's strategy for new management systems is to learn about existing processes and procedures and develop a simple manual that cross-references to other processes and programs within the organization. We then work with the organization to customize the system and procedures. A management system developed in partnership with Geosyntec is a good fit from the start and is flexible to evolve with the organization. For our clients with existing management systems, Geosyntec offers support with routine auditing and maintenance, system improvement, gap analysis with updated standards, developing and implementing corrective actions, and transitioning to new and/or revised standards. Our management system specialists include individuals with technical expertise across a broad range of disciplines who have studied and are training in management systems and who have worked in industry under management systems. We have experience with systems that conform to the ISO, OHSAS, RC, and EPA compliance-focused management system standards. The ISO 14001 standard for Environmental Management and the ISO 45001 standard for Occupational Safety and Health are widely used in manufacturing. Geosyntec is experienced in performing gap analyses of existing systems to determine what steps are needed to comply with these standards. We also perform internal audits, develop site-specific lists of legal requirements, develop standard operating procedures, and assist with corrective and preventative actions to improve management systems.

Environmental Permitting and Compliance

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Geosyntec provides a diverse portfolio of services to our public and private clients to improve their environmental and financial performance, manage risk, and reduce environmental liabilities consistent with their financial and stewardship goals. Our professionals have significant corporate, consulting, and government work experience and specialize in each of these sectors. Accordingly, we understand our clients' challenges and needs and provide appropriate solutions that consistently reduce risk exposure and add value to the bottom-line. Geosyntec delivers solutions in many areas of environmental compliance support, auditing, management systems, environmental studies and cleanup, infrastructure engineering and design, and natural resources assessment and restoration. We have completed nearly 10,000 projects worldwide with an outstanding and always improving safety record. Our experience delivers on the potential of innovative applications of proven and emerging technologies. Dynamic environmental laws, regulations, standards, and guidance demand a proactive approach in order for businesses to minimize environmental risk while maintaining economic benefit. Geosyntec's Environmental Management practitioners help our clients manage existing and potential liability associated with environmental, health and safety issues. Our clients have included utilities, government agencies, and companies in agriculture, manufacturing (chemical, food products, and technology), transportation, waste management, retail, and property development/management. Geosyntec assists clients with a variety of environmental compliance services. These services range from proactive to defensive/corrective, including the following: NPDES permitting support Air permitting support Toxics Release Inventory (TRI) reporting RCRA program development and implementation Environmental auditing program development and implementation Environmental performance measurement

Due Diligence

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The role of environmental due diligence during merger, divestiture, and acquisition (MD&A) activities has evolved significantly since the early years of conducting straightforward Phase I Environmental Site Assessments (ESAs) for the purpose of identifying potential environmental concerns. Today, transactional due diligence can encompass far beyond just the routine Phase I ESA, advancing to higher level deal optimization through evaluation of sustainable practices and environmental, social and governance (ESG) to not just mitigate, but optimize the environmental foot print of the transaction.  What once may have required only a small team of environmental professionals, has now developed into a requirement to assemble a myriad of inter-disciplinary professionals; skilled not just in environmental matters, but in financial and business matters as well with an aim of seeking value creation in addition to risk mitigation.  Our clients look to Geosyntec to become a strategic and sustainable business partner looking beyond just a response to regulatory requirements.   We understand that our clients may be driven by varying degrees of capitalization and risk tolerance.  Certain investments may be time-limited while other investments such as mergers may present a need for a longer term vision of risk mitigation.  We specialize in translating environmental risk into financial terms used for sound business decisions, requiring sophisticated integration of technical, regulatory, practical, and financial drivers.

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