Membership Committee
Current Employer: Senior Associate |Environmental Remediation Group Manager, Terracon Consultants, Inc., 10625 W. I-70 Frontage Road N, #3, Wheat Ridge, CO 80033, (720)338-1267
Email: erik.gessert@terracon.com
Erik is the Remediation Group Manager for Terracon’s Denver, Colorado office with over 20 years of professional experience in successfully managing remediation projects. Erik’s primary responsibilities include leadership, technical evaluation, senior project management, and quality review and he is a subject matter expert for Terracon on the topics of Light Non-Aqueous Phase Liquids (LNAPL) Site Management and high resolution site characterization (HRSC).
Prior to rejoining Terracon in 2018, Erik was the supervisor and a technical lead for the Colorado Division of Oil and Public Safety (OPS) Remediation team, where he was responsible for the identification, development, and implementation of major program initiatives. During his time with OPS, Erik was responsible for the successful implementation of enhanced risk-based closure criteria for the program, the implementation of the Recognized Environmental Professional program, and the development of OPS’s web-based Petroleum Remediation Guidance content.
Erik earned a BS in Civil Engineering from the University of Wisconsin-Madison in 2001 and moved to Denver shortly thereafter. Erik is happily married and the father of two children, two step-children, and two doggies. Collectively, we seemingly enjoy everything and will sleep sometime in the years to come.
Current Employer: Principal / Environmental Services Manager, CGRS Inc., 1301 Academy Court, Ft. Collins, CO, 80524, (970)493-7780
Email: Glen@cgrs.com
Glen Vallance is a Principal and Environmental Services Manager at CGRS’s corporate headquarters in Fort Collins, Colorado. Glen is a Recognized Environmental Professional (REP) with over 18 years of professional environmental experience, and he currently specializes in site assessment and remediation. In addition to managing multiple CGRS divisions, his experiences encompass a variety of tasks, including surface water quality studies, petroleum storage tank consulting, Phase I and II ESA, soil and groundwater assessment, aquifer characterization, and regulatory compliance. Glen is a graduate of Colorado State University’s Natural Resources Department with a bachelor’s degree in Watershed Science.
Current Employer: Senior Project Manager, Animas Environmental Services, LLC, 54 Cedar Lane, Ridgeway, CO, 81432, (720)537-6650
Email: aledgerwood@animasenvironmental.com
Ms. Ledgerwood is a Senior Project Manager with Animas Environmental Services, LLC and has 25 years’ experience in environmental consulting. Her project portfolio includes site investigations, corrective action plans, risk-based closures, emergency responses for environmental releases and natural disasters, and environmental due diligence projects. She has performed work for USEPA Regions 3, 6, 8, and 9 as well as FEMA, CDPHE, COGCC, Colorado Division of Mines, Reclamation, and Safety (DRMS), NMED, NMDOT, ADEQ, and Tribal and private industry clients. Ms. Ledgerwood received a BS from the Agricultural and Biological Engineering Department at Cornell University and an MSc from the School of Geosciences at the University of Edinburgh (Scotland).
Current Employer: Account Manager, AST Environmental, Inc., 99 S. Downing Street #302, Denver, CO, 80209, (513)675-8511
Email: mdean@astenv.com
Mitch has worked in the environmental industry for 5 years. After receiving his undergraduate degree in environmental sciences from The Ohio State University he started working in hazardous waste management at Clean Harbors for two years in Cincinnati, OH. He moved to Denver, CO and was hired by AST Environmental and started working in environmental remediation.
Mitch is involved with many aspects of the remediation process and spends time in both the office and field. He has been involved with injections, soil and water sampling, site characterization, and remedial designs with the end goal of site closure. The designs and projects he is involved with are in-situ injections and soil mixing applications of technologies delivered as slurries.
Mitch joined the CEMS membership, Networking, and Outreach committee in order to get more involved and form relationships with local environmental experts and help spur growth and involvement for CEMS.
Mitch moved to Colorado to be closer to the mountains. He is an avid skier, climber, and hiker who loves spending his free time in the mountains with his friends and dog, Rosie. He loves getting out around Denver and the occasional sports game.
Current Employer: Project Manager,Weaver Consultants Group (WCG), 7340 E. Caley Avenue, Suite 110, Centennial, CO, 80111, (312)478-8972
Email: pgruca@wcgrp.com
Paul Gruca is a Certified Water Professional and serves as a Project Manager for Weaver Consultants Group (WCG) with over 13 years of environmental consulting experience. He joined WCG at their Chicago headquarters in 2011, primarily responsible for environmental due diligence, dig/haul and in-situ injection remedial projects, and state voluntary cleanup program closures for projects across the Midwest. Paul transitioned to WCG’s Remediation Services Group with a move to Denver in 2019. Paul’s primary duties include the design, construction, implementation, and performance evaluations of automated and self-implemented remedial programs. These remedial programs utilize technologies employing enhanced reductive dechlorination, chemical oxidation/reduction, bio-augmentation, zero-valent iron, and others through various application approaches. Paul is also a certified Industrial Wastewater Treatment Operator, managing multiple wastewater treatment plants and ex-situ groundwater/vapor remedial treatment systems. These remediation projects and programs are located across the country.
Paul earned a BS in Environmental Geosciences from Northern Illinois University with a focus on Geology. Originally from Chicagoland, Paul loved living in downtown Chicago, but always had a desire to move west for the topography and scenery, Paul moved to Denver in 2019 to focus on large scale environmental remediation projects. Paul enjoys hiking and bicycling, loves cooking and walks with his dog Lenny, and recently rekindled a former semi-professional paintball career from his youth.
Current Employer: Project Manager, CGRS Inc., 1301 Academy Court, Ft. Collins, CO, 80524, (970)493-7780
Email: dkinnaird@cgrs.com
Drezden Kinnaird is an accomplished Project Manager, with a specialization in AQCC regulatory compliance, multimedia environmental management, and liaising on behalf of local governments and oil and gas operators in Colorado. Drezden has over nine years of experience in the environmental industry and has worked in various roles where she managed multiple complex projects and client portfolios. Drezden is passionate about environmental regulations, and her advocacy for client interests has played a pivotal role in her frequent participation in government stakeholder processes.
Drezden holds a Bachelor’s Degree in Environmental Science and Technology with a concentration in Pollution Control & Monitoring, as well as a Minor in Geographic Information Science and Cartography from Colorado Mesa University. She is also a Registered Environmental Manager (REM) with the National Registry of Environmental Professionals.
Drezden was invited as a panelist for the Oil & Gas Discussion Panel at Envirofest2019, organized by the Rocky Mountain Association of Environmental Professionals, where she shared her insights on the changing regulatory landscape in Colorado. Outside of work, Drezden enjoys cooking and gardening. She joined the CEMS membership, Networking, and Outreach committee in 2023 in order to get more involved in expanding CEMS membership to young professionals.