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November 1, 2025

Longenecker & Associates is Now a Part of Geosyntec Consultants

Trusted Expertise, Broader Capabilities

In 2025, Longenecker & Associates (L&A) joined Geosyntec Consultants, a recognized leader in environmental and infrastructure solutions worldwide. This partnership combines L&A’s decades of experience supporting the environmental remediation, nuclear power, and scientific discovery missions of the United States Department of Energy with Geosyntec’s advanced technical capabilities and global reach.

While L&A now operates under the Geosyntec name, our mission remains unchanged. Clients continue to work with the same experienced staff they know, now backed by a global network of experts. Together, we provide integrated solutions for project delivery, mission and regulatory assurance, and operations support, complemented by scientists and engineers with demonstrated success in environmental management and remediation across federal, industrial, and international markets.

We can now deliver deeper insights, more options, and better outcomes for your projects today and in the future.

Federal Services

  • Regulatory Assurance

    Federal and commercial clients must successfully navigate a web of environmental and regulatory requirements to deliver large and complex projects safely, compliantly, on cost, and on time.

  • Strategic Communications and Business Strategy and Execution

    Clients can face many obstacles to business and mission success, including when implementing winning strategies for proposals, developing and deploying strategic communications, navigating international government departments, and selecting and implementing effective technologies for mission need.

  • Field Operations Support

    Clients across the United States Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) complex, as well as commercial clients in the United States and internationally, need field operations support for their complex and high-hazard projects and sites.

  • Mission Assurance

    Clients across the United States Department of Energy (DOE) and National Nuclear Security Administration (NNSA) complex face many challenges to mission performance. To build successful programs and projects, they need site-specific solutions that address critical challenges to mission success and focus on improvement opportunities.

  • Project Delivery

    Federal and commercial clients executing major capital asset and general plant projects face persistent challenges. These can include defining mission needs, establishing the business case, securing funding, managing cost and schedule, addressing technical complexity, and navigating regulatory and operational readiness requirements.

  • Government: Federal Departments and Agencies

    Federal clients choose Geosyntec to work on their most challenging projects, where inventive technical and management approaches are required. We have been selected through Brooks Act Quality-Based Section procurements to implement innovative solutions, often resulting in first-to-field application of new technologies that reduce cost and expedite project completion.

Additional Information

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Lead Practitioners

Projects: Longenecker & Associates

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