David Walker is experienced in a variety of engineering and environmental projects involving landfill design, landfill gas collection and control system design, air permitting, regulatory compliance and reporting, construction quality assurance, brownfield redevelopment, and environmental sampling.
Jim Walsh, PE, BCEE, is the Chairman of the Board of SCS Engineers effective January 1, 2024. He served as our President and CEO for 22 years and is one of our National Experts on Elevated Temperature Landfills. He has worked at the forefront of sustainable solid waste management, sanitary landfills, and landfill gas (LFG) for more than 40 years. Mr. Walsh regularly serves as a Project Director and Reviewing Principal for SCS landfill and LFG projects. His project experience, coupled with his involvement in professional and industrial associations, has earned Mr. Walsh an international reputation in these specialty fields. He has authored numerous publications and technical support documents and presents regularly at environmental conferences.
Jim Walsh, PE, BCEE, is the Chairman of the Board of SCS Engineers effective January 1, 2024. He served as our President and CEO for 22 years and is one of our National Experts on Elevated Temperature Landfills. He has worked at the forefront of sustainable solid waste management, sanitary landfills, and landfill gas (LFG) for more than 40 years. Mr. Walsh regularly serves as a Project Director and Reviewing Principal for SCS landfill and LFG projects. His project experience, coupled with his involvement in professional and industrial associations, has earned Mr. Walsh an international reputation in these specialty fields. He has authored numerous publications and technical support documents and presents regularly at environmental conferences.
Practice Areas Have Included:
Leadership in Landfill Engineering. Over 40 years of professional experience on landfill projects. He served as Project Manager and primary author of the U.S. EPA landfill manual. He served as Project Manager and Chief Investigator on several U.S. EPA landfill R&D efforts relating to leachate, gas, and liner/cap performance. He has been engaged on over 100 landfill design and permitting projects, including sites with double composite liner systems. He has managed or directed several successful greenfield and landfill expansion permits with individual design capacities in excess of 25 million tons of solid waste.
Leadership in Landfill Gas. Over 40 years of professional experience on landfill gas (LFG) projects. Past Director of the leading LFG professional organization, the SWANA Landfill Gas Division. Received top award in landfill gas practice, the SWANA Landfill Gas Distinguished Service Award in 1997. He has served as Principal Investigator multiple landfill gas R&D projects for U.S. EPA, U.S. DOE, and Gas Research Institute. He has authored numerous publications and technical support documents in LFG. He has presented dozens of times on LFG at environmental conferences. He has been engaged as chief design engineer, Principal Investigator, or Project Manager on over 300 landfill gas projects over the years. Landfill gas related subjects have included gas migration and control, energy recovery, odor management, and compliance with air and solid waste rules including CAA, NSPS, Title V, NSR, PSD, NESHAP, and Subtitle D.
Leadership on Landfill Fire and Elevated Temperature Landfills. Principal investigator or chief engineer on over thirty dedicated landfill fire and elevated temperature landfill projects. He has provided guidance to landfill operators to avoid landfill fires. He has investigated landfill fires in-situ, and developed management and mitigation programs to address landfill fires and related events when they do occur. He has presented at environmental conferences on the subject of landfill fires. He served on the Ohio EPA Committee formed to address landfill fires and elevated temperature landfills in the state, and assisted in the development of the Ohio EPA Guidance Document on the subject.
Contact Jim at 513-421-5353 or
Charles Warren, PE, is experienced in landfill engineering, solid waste facilities design, site development, and mine planning experience. He conducts solid waste permitting, stormwater management, facility design, mine closure, and design projects for municipal and private clients. Recent experience includes problem-solving for elevated temperature landfills.
Tyler Warren, EIT, is experienced in civil and environmental engineering. His project experience includes landfill design and permitting, environmental monitoring, landfill construction, and many other facets of environmental compliance. Mr. Warren is a Federal Aviation Authority (FAA) certified commercial Unmanned Aerial Vehicle (UAV) pilot and provides aerial imaging and topographic mapping services for clients in the Midwest.
Tyler Warren, EIT, is experienced in civil and environmental engineering. His project experience includes landfill design and permitting, environmental monitoring, landfill construction, and many other facets of environmental compliance. Mr. Warren is a Federal Aviation Authority (FAA) certified commercial Unmanned Aerial Vehicle (UAV) pilot and provides aerial imaging and topographic mapping services for clients in the Midwest.
Ms. Tyler Watkins is experienced in environmental remediation and compliance. She is responsible for Phase I and II Environmental Site Assessments (ESAs), multimedia sampling and reporting (soil, groundwater, surface water, sediment, soil vapor, air), as well as compliance monitoring, permitting, document preparation, and proposals. She works directly with our local clients and regulatory agencies, ensuring timeliness of reports and compliance.
Tyler Watkins is experienced in environmental remediation and compliance. She is responsible for Phase I and II Environmental Site Assessments (ESAs), multimedia sampling and reporting (soil, groundwater, surface water, sediment, soil vapor, air), as well as compliance monitoring, permitting, document preparation, and proposals. She works directly with our local clients and regulatory agencies, ensuring timeliness of reports and compliance.
Ms. Watkins’ previous experience includes field investigations and report production involving groundwater monitoring, Perfluorooctanoic acid (PFAS) sample collection, excavation events related to South Coast Air Quality Management District (SCAQMD) Rule 1466 monitoring, preparation of sampling plans for Phase II investigations, stormwater inspections and reporting, and related field activities. She has developed a conceptual site model to request closure for a service station site, and has overseen contractors in a variety of field activities, including Organochlorine pesticides (OCP) testing in school sites, aerially deposited lead surveys, and soil vapor monitoring. She has conducted site investigations related to federal and state hazardous waste; produced reports for review by oversight agencies such as the Regional Water Quality Control Board (RWQCB), CalTrans, and California Department of Toxic Substances Control (DTSC); prepared Phase I ESA reports; and logged and sampled soil using boring techniques that included sonic drilling, hand auger, and direct push equipment. She has also overseen Phase II projects, and coordinated the installation and abandonment of wells, including obtaining permits, contact with subcontractors, and field oversight. She also has expertise in soil vapor well installation and monitoring.
Liam Watson is a Vice President and our Director of Information Technology.
Lance Weaver has over two decades of experience in groundwater and stormwater sampling, and maintenance and repair of related equipment. In addition to his experience with asbestos and lead-based paint sampling, as well as sampling from soil and soil vapor extraction wells, he is experienced in the maintenance and repair of soil vapor extraction (SVE) systems, and monitoring groundwater and stormwater systems. Mr. Weaver is also experienced in Global Information System (GIS) mapping, source collection, database management, and digital and manual drafting.
Lance Weaver has over two decades of experience in groundwater and stormwater sampling, and maintenance and repair of related equipment. In addition to his experience with asbestos and lead-based paint sampling, as well as sampling from soil and soil vapor extraction wells, he is experienced in the maintenance and repair of soil vapor extraction (SVE) systems, and monitoring groundwater and stormwater systems. Mr. Weaver is also experienced in Global Information System (GIS) mapping, source collection, database management, and digital and manual drafting.
He is trained to operate and calibrate air and water monitoring equipment, including RAE PIDs, Foxboro FIDs, GEM landfill gas (LFG) detectors, RKI Eagle gas detectors, and Horiba and water quality meters (QED) and pumps.
Software experience includes AutoCAD, ARC/INFO, ARC/VIEW GIS, Windows 10 Professional, and UNIX.
Travis Weber’s main area of concentration is risk analysis. He is responsible for the documentation of Process Safety Management Programs (PSM), Risk Management Programs (RMP), and California Accidental Release Prevention (CalARP) Programs for facilities using regulated substances. This work includes preparing all necessary documentation for compliance with the PSM/RMP/CalARP regulation, and modeling the potential off-site consequences of potential releases, compliance audits, and other environmental study projects for municipal and private clients.
Travis Weber’s main area of concentration is risk analysis. He is responsible for the documentation of Process Safety Management Programs (PSM), Risk Management Programs (RMP), and California Accidental Release Prevention (CalARP) Programs for facilities using regulated substances. This work includes preparing all necessary documentation for compliance with the PSM/RMP/CalARP regulation, and modeling the potential off-site consequences of potential releases, compliance audits, and other environmental study projects for municipal and private clients.
Prior to joining SCS Engineers, Mr. Weber acquired experience in the oil and gas industry while working for an oil company in Pennsylvania. He implemented his knowledge of ESRI Geographic Information Systems to develop maps for project planning, legal correspondence, and engineering operations. He was also involved in the facilitation of permits, as well as correspondence with state and federal environmental protection agencies.
Anastasia Welch, PE, is the Business Unit Director for SCS Engineer’s Central Region, effective January 1, 2024. She is a Vice President and Project Director with nearly 25 years of experience in solid waste management and civil engineering. Her expertise centers on solid waste management, including landfill design and permitting, construction oversight, operational metrics, compliance, and long-term planning. She is a Professional Engineer licensed in Kansas, Missouri, Iowa, and North Dakota.
Anastasia Welch, PE, is the Business Unit Director for SCS Engineer’s Central Region, effective January 1, 2024. She is a Vice President and Project Director with nearly 25 years of experience in solid waste management and civil engineering. Her expertise centers on solid waste management, including landfill design and permitting, construction oversight, operational metrics, compliance, and long-term planning. She is a Professional Engineer licensed in Kansas, Missouri, Iowa, and North Dakota.
Her solid waste management experience includes groundwater monitoring, landfill design and permitting, construction oversight, air compliance issues, bioreactor studies, and alternative cover design. Although based in our Central Region, Ms. Welch leverages the experience of SCS personnel from across the company to meet our clients’ expectations and needs.
Denise Wessels, PE, is a Vice President of SCS Engineers, and a Project Director with our Landfill Engineering Group in the Reading, PA office. She has over two decades of experience in the waste management industry and environmental consulting, including landfill design, project management, regulatory compliance, permitting, environmental monitoring and studies, auditing, and budgeting.
Denise Wessels, PE, is a Vice President of SCS Engineers, and a Project Director with the Landfill Engineering Group in the Reading, PA office. She has over two decades of experience in the waste management industry and environmental consulting, including landfill design, project management, regulatory compliance, permitting, environmental monitoring and studies, auditing, and budgeting.
Stacie Whitmer is an Environmental Scientist and Project Manager with SCS Engineers. She has over seventeen years of experience in environmental consulting. Project experience includes site assessments, extent of contamination studies, landfill flare and gas monitoring systems, groundwater sampling and statistical analysis of groundwater data, regulatory compliance, and NPDES services.
Stacie Whitmer is an Environmental Scientist and Project Manager with SCS Engineers. She has over seventeen years of experience in environmental consulting. Project experience includes site assessments, extent of contamination studies, landfill flare and gas monitoring systems, groundwater sampling and statistical analysis of groundwater data, regulatory compliance, and NPDES services.
Ms. Whitmer has worked with several solid waste disposal facilities in Arkansas to help bring the Landfills into compliance with applicable Federal and State solid waste regulations. In particular, she has prepared several groundwater sampling and analysis plans, statistical and contingency plans, and explosive gas monitoring plans for several landfill sites.
Ms. Whitmer also has extensive experience in managing groundwater sampling, statistics utilizing Sanitas for GroundwaterTM and DumpstatTM statistical programs, reporting, and compliance associated with solid and hazardous waste landfills. In addition, she has performed many geologic, hydrogeologic, and compliance projects associated with solid and hazardous waste landfills.
Daniel Wiens is a project engineer with experience in the civil and environmental engineering fields. His project experience includes landfill design and permitting, environmental monitoring, landfill construction, agriculture biogas capture design and many other facets of environmental compliance.
Andrew Wilcox is experienced in the operation, monitoring and sampling of groundwater corrective action systems. His expertise includes groundwater sampling and environmental control system operation to meet Bay Area and Central Valley APCD, Title V, RWCQB, and state regulations and requirements.
Andrew Wilcox is experienced in the operation, monitoring and sampling of groundwater corrective action systems. His expertise includes groundwater sampling and environmental control system operation to meet Bay Area and Central Valley APCD, Title V, RWCQB, and state regulations and requirements.
Mr. Wilcox’s experience includes implementation of sampling plans and maintenance required to keep the systems operational and in compliance with various prescribed operating parameters and goals; performance, supervision, and/or assistance in required maintenance and repairs; and interaction with and/or management of subcontractors, laboratories, and vendors needed to assist with maintenance and sampling of the systems. He is also responsible for preparing daily field logs, recording field observations, preparing samples for shipment, and recommending actions to be taken.
Lisa Wilkinson, PE, is a Vice President and Project Manager at SCS with nearly three decades of experience in landfill engineering design, landfill gas (LFG), permitting, civil and environmental engineering, financial feasibility evaluations, storm water design, and construction quality assurance at landfills and solid waste facilities. Ms. Wilkinson also has experience working on foundation and structural design teams for various facilities, and she is proficient in the computerized analysis of engineering designs. She is a licensed Professional Engineer in New York, Pennsylvania, and Vermont.
Lisa Wilkinson, PE, is a Vice President and Project Manager at SCS with nearly three decades of experience in landfill engineering design, landfill gas (LFG), permitting, civil and environmental engineering, financial feasibility evaluations, storm water design, and construction quality assurance at landfills and solid waste facilities.
Ms. Wilkinson also has experience working on foundation and structural design teams for various facilities, and she is proficient in the computerized analysis of engineering designs.
She is a licensed Professional Engineer in New York, Pennsylvania, and Vermont, and has a Master’s Degree in Environmental Engineering.
Ron Wilks is a Vice President. He has a degree in business administration (marketing and personnel management) and has over four decades of experience. His technical expertise is environmental compliance relating to landfills. He is responsible for training personnel in the Field Services Southwest and Southeast Regions, and he is active with the SWANA LFG Training and Field Practices Committee. Mr. Wilks is a client services manager for all aspects of projects the include design requirements, coordination of designs, construction implementation, and operations management. He is also the primary system troubleshooter and investigator for LFG and leachate management systems.
Ron Wilks is a Vice President. He has a degree in business administration (marketing and personnel management) and has over four decades of experience. His technical expertise is environmental compliance relating to landfills. He is responsible for training personnel in the Field Services Southwest and Southeast Regions, and he is active with the SWANA LFG Training and Field Practices Committee. Mr. Wilks is a client services manager for all aspects of projects the include design requirements, coordination of designs, construction implementation, and operations management. He is also the primary system troubleshooter and investigator for LFG and leachate management systems.
Contact Ron at 817-358-6104 or
Brandon Williams has experience with the design and build of digester gas to RNG facilities throughout the United States. He has also worked in the construction industry, specifically in the areas of plumbing and natural gas utility distribution.
Thomas Williams, EIT, is responsible for technical project work, including the preparation of engineering drawings and calculations for landfill engineering, landfill gas management, landfill environmental systems, and other environmental projects. He conducts solid waste permitting, landfill cell design, landfill gas system design, airspace calculations, CQA, stormwater analysis, and cost estimations for municipal and private clients. He has also manages landfill design and construction administration tasks.
Thomas Williams, EIT, is responsible for technical project work, including the preparation of engineering drawings and calculations for landfill engineering, landfill gas management, landfill environmental systems, and other environmental projects. He conducts solid waste permitting, landfill cell design, landfill gas system design, airspace calculations, CQA, stormwater analysis, and cost estimations for municipal and private clients. He has also manages landfill design and construction administration tasks.
Eric Williams is a Project Director and one of our National Experts on Brownfields and Landfill Redevelopment. He has four decades of experience in the environmental industry as a senior executive and project director, including all facets of environmental consulting focusing on serving public and private sector clients facing the complex issues associated with environmentally-challenged real estate. Eric has particularly deep experience with redevelopment of brownfield properties, having spent almost half of his career as a developer of brownfield sites. His focus area is the southwestern U.S., and he is also a national resource on redevelopment.
Eric Williams is a Project Director and one of our National Experts on Brownfields and Landfill Redevelopment. He has four decades of experience in the environmental industry as a senior executive and project director, including all facets of environmental consulting focusing on serving public and private sector clients facing the complex issues associated with environmentally-challenged real estate. Eric has particularly deep experience with redevelopment of brownfield properties, having spent almost half of his career as a developer of brownfield sites. His focus area is the southwestern U.S., and he is also a national resource on redevelopment.
Contact Eric at (858) 463-0398 or
Michael Wolf is a Senior Project Professional in our Energy Division.
Chris Woloszyn is a Senior Project Professional with SCS Engineers and is based in the Lancaster, Pennsylvania office. Since joining with SCS in 2017, has reviewed contract submittals for approval, assisted with report documentation for NSPS reports to the EPA, prepared design plans for landfill gas collection and leachate force main systems, conducted aerial UAS topography scans, UAS 3D modeling, and has provided construction quality assurance for of gas extraction wells with related conveyance piping systems as well as engineered final cover systems.
Chris Woloszyn is a Senior Project Professional with SCS Engineers and is based in the Lancaster, Pennsylvania office. Since joining with SCS in 2017, has reviewed contract submittals for approval, assisted with report documentation for NSPS reports to the EPA, prepared design plans for landfill gas collection and leachate force main systems, conducted aerial UAS topography scans, UAS 3D modeling, and has provided construction quality assurance for of gas extraction wells with related conveyance piping systems as well as engineered final cover systems.
Pierce Wu has over two decades of construction management and leadership experience. He has a comprehensive background working in construction, architecture, and business. Mr. Wu has organized, coordinated and managed residential and commercial construction projects in Taiwan, China, and the United States. He is fluent in English, Mandarin, Taiwanese, and Shanghainese.
Pierce Wu has over two decades of construction management and leadership experience. He has a comprehensive background working in construction, architecture, and business. Mr. Wu has organized, coordinated and managed residential and commercial construction projects in Taiwan, China, and the United States. He is fluent in English, Mandarin, Taiwanese, and Shanghainese.
Kenton Yang, PE, is a Project Director in our Raleigh, North Carolina, office, providing landfill engineering and solid waste management consulting services to the Carolinas and beyond. He has over 19 years of experience in civil and environmental engineering, with expertise in landfill siting and permitting; and facility design, operations, and construction management for municipal solid waste landfills (Subtitle D), CDD landfills, utility coal ash landfills, and household hazardous waste and multi-material waste and recycling convenience centers. He has Bachelor’s and Master’s Degrees in Environmental Engineering from the University of Florida at Gainesville, and is a licensed Professional Engineer in North Carolina.
Kenton Yang, PE, is a Project Director in our Raleigh, North Carolina, office, providing landfill engineering and solid waste management consulting services to the Carolinas and beyond. He has over 19 years of experience in civil and environmental engineering, with expertise in landfill siting and permitting; and facility design, operations, and construction management for municipal solid waste landfills (Subtitle D), CDD landfills, utility coal ash landfills, and household hazardous waste and multi-material waste and recycling convenience centers. He has Bachelor’s and Master’s Degrees in Environmental Engineering from the University of Florida at Gainesville, and is a licensed Professional Engineer in North Carolina.
Mr. Yang is experienced in solid waste facility site development projects, leachate management, and environmental regulatory compliance, including air quality for landfills; landfill gas collection, control design, and operations. He has conducted a variety of solid waste management assessments and planning projects and sanitary sewer rehabilitation design and construction management.
He has worked with numerous counties and cities throughout North Carolina, serving as the client contact in addition to managing capital improvement projects, annual environmental compliance assistance, solid waste management plans, and on-call services.
Kenton conducted landfill site selection and site suitability permitting for a coal ash landfill for a power utility in the southeast, as well as design, permitting, and construction management for two of its phases. He assisted in landfill operational issues, including stormwater control and leachate management, and was responsible for site compliance associated with EPA’s CCR rule.
Dr. Yang is a geochemist/engineer experienced in identifying and developing solutions to geochemical questions utilizing experimental design, analytical chemistry, geochemical modelling, geological characterization, and engineering process design. He is also experienced in advancing research from early technology readiness levels along pathways for potential commercialization and/or technological transfer. Dr. Yang’s expertise is in critical metal and other rare earth elements resource assessment and extraction processes.
Dr. Yang is a geochemist/engineer experienced in identifying and developing solutions to geochemical questions utilizing experimental design, analytical chemistry, geochemical modelling, geological characterization, and engineering process design. He is also experienced in advancing research from early technology readiness levels along pathways for potential commercialization and/or technological transfer. Dr. Yang’s expertise is in critical metal and other rare earth elements resource assessment and extraction processes.
