GEI’s engineers and scientists work to provide lasting solutions by surveying and monitoring local habitats, providing site and project permitting, and working with clients and communities to plan, design, and implement their proposed projects, while improving local environments and ecosystems. Our environmental expertise stems from more than 30 years of working with federal and state regulatory agencies, and helping our clients navigate problems by providing solutions that lead to implementable projects.

Our Focus

GEI employee in yellow vest taking notes

Due Diligence

A core element of GEI’s practice is environmental due diligence. We have performed thousands of due diligence investigations for potential buyers, sellers, and for refinancing. The due diligence may be as simple as an ASTM Environmental Site Phase I Assessment (ESA) consisting of historical and regulatory document reviews and a site visit or a complex investigation requiring subsurface investigation and developing estimates of cleanup costs. We are aware of the time and confidentiality constraints that may accompany significant real estate or corporate acquisitions and are experienced at performing multiple assessments nationwide over short timeframes.

site characterization and remediation - GEI

Site Characterization, Remediation and Redevelopment

GEI employs a risk-based approach and works with clients to provide environmentally friendly solutions that reduce costs and accelerate project completion. For the protection of human health, our strategies rely on both state and the U.S. Environmental Protection Agency (EPA) regulatory standards, enabling us to tailor the use of innovative technologies that provide compliant results.

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Risk Assessment

GEI provides industry-leading scientific expertise in human health and ecological risk assessment, environmental toxicology, exposure and effects assessments and indoor air pollution, which are applied to support the cleanup of hazardous waste sites. GEI offers a full range of ecological risk assessment services to successfully evaluate, interpret and communicate ecological risks associated with chemical and physical stressors in both the aquatic and terrestrial environments. Our human health risk assessors understand the highly complex set of factors that influence multi-exposure-pathway risk assessment such as inhaling vapors emanating from soils, ingesting contaminated soil, water or food, and making dermal contact contaminated with water or soils.

Manufactured Gas Plants

GEI has been a leader in managing former manufactured gas plant (MGP) sites for more than 30 years. We have been involved in more than 600 MGP site historical investigations, site characterizations, risk assessments and feasibility studies for both utility and industrial clients, and have completed more than 100 MGP site remedial designs.

Environmental planning and design - GEI

Environmental Planning and Permitting

Today’s environmental regulations are complex and challenging. GEI’s clients need expert assistance to navigate through the labyrinth of federal, state and local regulatory compliance requirements. GEI’s planners, permit and climate change experts, scientists, biologists, archaeologists and architectural historians help our clients obtain required project permits with acceptable terms and conditions to build your project to specifications, while staying on budget and schedule.

natural resources - GEI

Natural Resources Assessment and Management

GEI has extensive experience surveying, assessing and managing terrestrial and aquatic biota and habitats across the U.S. Our scientists encompass numerous fields of expertise including botany, wildlife, invertebrates, reptiles and amphibians, birds, fish and mussels. We routinely conduct species and habitat inventories and prepare resource management and mitigation plans to minimize project impacts, obtain project approvals and maintain and/or restore native ecosystems.

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Ecological Restoration Planning and Design

GEI possesses the in-house staff to assess, design and implement all phases of ecological restoration to support projects from inception to completion. Our skilled and integrated team of ecological engineers, restoration ecologists, botanists, fisheries and wildlife biologists, soil and water quality specialists and design professionals work together to integrate ecological principles with key elements of planning, site engineering and land use planning. We respond to all project elements, needs and interests of our clients, while meeting regulatory standards.

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Ecological Laboratory Testing

GEI’s in-house laboratory offers a wide variety of biological, chemical and toxicological testing services. Our laboratory services include identification of benthic invertebrates, ambient and whole effluent toxicity testing and low-level nutrient chemistry, providing the breadth and quality of data necessary for comprehensive ecological analyses of lakes, streams, estuaries, wetlands and other environments.

GEI also offers the following in-house laboratory services: Whole Effluent Toxicity, Bug ID, Nutrients, Coliforms, and more.

To learn more contact Laboratory Director, Natalie Love: or 303.264.1070.

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Ecotoxicology and Water Quality

Assessing the impacts of chemical contamination on ecological systems integrates various aspects of toxicology, environmental chemistry, aquatic and terrestrial ecology, laboratory toxicity testing and statistical analyses. GEI offers services to support these studies, including reviewing the scientific literature, preparing toxicity profiles for individual chemicals, conducting new aquatic or terrestrial toxicity tests to fill data gaps in the literature and coupling toxicity analyses with a deep understanding of aquatic or terrestrial ecology.


Solid Waste Services

GEI’s experts are experienced in providing comprehensive solid waste planning, permitting, design and construction services to public and private sector solid waste facility clients. Our staff is recognized throughout the nation for decades of experience in developing innovative and technically sound engineering solutions to fit our client’s needs and project challenges. GEI can assist on projects from the planning and siting stage, through permitting and design, construction, performance monitoring and closure. The unique combination of design teams, environmental staff and construction services allows our teams to provide cost-effective solutions to any solid waste management need.

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