David Alden
Tersus Environmental
Manager of Technical Services, 

David serves as the Manager of Technical Services at Tersus Environmental, where he is a dedicated professional with extensive experience in environmental engineering and technical services. In this pivotal role, David is instrumental in fostering innovation and excellence within the realm of environmental solutions. He provides crucial technical support for Tersus' biotechnology-based solutions, specializing in the management of complex environmental liabilities and cost reduction for site closure.

Having spent four years in the upstream oilfield sector, David contributed significantly to offshore well tests and completion design and installation in the Gulf of Mexico. His expertise extends to in situ oil-shale extraction experiments in the Piceance Basin, Northwestern Colorado, with a primary focus on safeguarding groundwater.

A key aspect of David's work revolves around the development of innovative technologies for restoring groundwater and soil in challenging sites. He has authored three patents on reductive bioremediation and in situ chemical reduction, with US Patent 11,123,779 B2 titled "Method and a Chemical Composition for Accelerated In Situ Biochemical Remediation" being a notable contribution. Additionally, he has eight pending patent applications for groundwater contaminant remediation.

Managing the company’s Compound-Specific Isotope Analysis (CSIA) projects, David showcases his commitment to staying at the forefront of industry advancements by applying cutting-edge techniques to assess environmental contaminants. David leverages his expertise in CSIA to provide a quantitative means for differentiating reaction pathways—shedding light on the intricate processes of abiotic and biotic degradation. This not only enhances our understanding of environmental challenges but also paves the way for more targeted and effective solutions.

Contact: [email protected] 

Francisco J. Barajas-Rodriguez, PhD
AECOM
Environmental Engineering Discipline Lead I

Francisco is an environmental engineer discipline lead and treatability subject matter specialist working on research, development, and evaluation of treatment technologies for remediation and industrial wastewater treatment. He has collaborated with project managers, engineers, and remediation practitioners in over 100 projects, conducting literature reviews and treatability testing to improve project performance, lower treatment costs, and support technology selection.

These projects include landfill leachate treatment, surface water treatment to complex industrial wastewater treatment, chemical and biological treatment, in-situ stabilization of waste and sediments, and immobilization of coal combustion residuals (CCR) heavy metals in groundwater.

Francisco’s interests cover screening and evaluation of treatment technologies designed emerging contaminants (PFAS, microplastics) treatment and resource recovery, such as biological processes aimed at recovering polymers, metals, and minerals. Francisco is also a member of the Interstate Technology and Regulatory Council (ITRC) technical teams for Sustainable Waste Management from Energy Resources, PFAS, and 1,4-dioxane, and Microplastics.

Contact: [email protected]

Sebastian Harrison
Center for Creative Land Recycling 
Environmental Engineering Consultant

Sebastian joined CCLR with 7 years of experience in the Chemical Industry as a Remediation Project Manager. His past work included assisting in all facets of Sustainability such as brownfield revitalization, waste management, environmental policy, responsible care, solar implementation, and life cycle analysis. Since joining CCLR, he has been fundamental in the roll-out and management of the Equitable Community Revitalization Grant, assisting applicants and grantees plan and execute projects in the investigation and revitalization of brownfields across the state of California. He draws from his past experience to help applicants design budgets aligned with remediation success and assists grantees with contracting events. While at CCLR he has also acted as a subject matter expert on Sustainable Remediation and helped explain how site clean-up can be linked towards broader Social, Environmental, and Economic goals.

Contact: [email protected]

David Foss
MassDEP - Bureau of Waste Site Cleanup
Statewide Brownfields Coordinator

David is a hydrogeologist with over 30 years of experience conducting and managing environmental assessment, remediation, and redevelopment at Brownfield sites. He is a Certified Professional Geologist and Licensed Site Professional.

Before joining MassDEP in 2022, David worked as an environmental consultant serving a wide range of public and private stakeholders, including more than 40 Massachusetts municipalities and Regional Planning Agencies. He collaborates with the U.S. EPA and MassDevelopment to promote assessment, cleanup, and redevelopment at Brownfield sites across the Commonwealth.

On behalf of MassDEP, David serves on the Regulatory Committee of BCONE (Brownfields Coalition of the Northeast) and the ASTSWMO (Association of State and Territorial Solid Waste Management Officials) Brownfields Focus Group.

Contact: [email protected]