Steven Croasdale is a Project Manager in our Operations, Maintenance, and Monitoring (OM&M) Division. He has over 15 years of experience in landfill gas (LFG) system operations monitoring, maintenance, migration control and recovery projects, and NSPS compliance. Field responsibilities have included routine testing, monitoring, and maintenance; repair of LFG collection headers, pneumatic pumps, extraction wells, and blower/flare facilities. Mr. Croasdale also performs non-routine troubleshooting and repairs as well as emergency response services.
Steven Croasdale is a Project Manager in our Operations, Maintenance, and Monitoring (OM&M) Division. He has over 15 years of experience in landfill gas (LFG) system operations monitoring, maintenance, migration control and recovery projects, and NSPS compliance. Field responsibilities have included routine testing, monitoring, and maintenance; repair of LFG collection headers, pneumatic pumps, extraction wells, and blower/flare facilities. Mr. Croasdale also performs non-routine troubleshooting and repairs as well as emergency response services.
As the Sub-region Manager, Mr. Croasdale is routinely involved with work scope implementation, scheduling of field technicians, data review, interpretation, and assessment and coordination with the Engineers. Responsibilities have included, report preparation and review, Health & Safety Plan preparation and implementation, and providing support in regulatory compliance; i.e., compliance with Clean Air Act requirements and off-site migration regulations.
Mr. Croasdale construction background includes installation and startup of blowers, flares, pumps, and compressors. These experiences have included both construction of new and expanded systems and repair and renovation of existing systems.
Chris Crosby is a Project Director and one of our National Experts on Emerging Contaminants. He has nearly two decades of professional experience in the environmental consulting field. He manages complex environmental site assessments (ESAs), subsurface investigations, and remediation and construction projects to navigate regulatory requirements and meet client objectives. His experiences includes investigating and remediating properties that have impacted soil and groundwater by a variety of constituents of concern, including total petroleum hydrocarbons, chlorinated solvents, volatile organic compounds (VOCs), pesticides, lead and other heavy metals, and PFAS.
Chris Crosby is a Project Director and one of our National Experts on Emerging Contaminants. He has nearly two decades of professional experience in the environmental consulting field. He manages complex environmental site assessments (ESAs), subsurface investigations, and remediation and construction projects to navigate regulatory requirements and meet client objectives. His experiences includes investigating and remediating properties that have impacted soil and groundwater by a variety of constituents of concern, including total petroleum hydrocarbons, chlorinated solvents, volatile organic compounds (VOCs), pesticides, lead and other heavy metals, and PFAS.
He routinely prepares technical environmental documents clearly describing environmental conditions to meet regulatory agency compliance. These documents include Work Plans, property mitigation plans, soil management plans (SMPs), corrective action plans (CAPs), remedial action plans (RAPs), ESA reports, groundwater monitoring reports, health risk assessments (HRAs), and property closure reports. He has experience managing groundwater monitoring programs, drilling operations (vertical and horizontal), remediation, and construction oversight. He has implemented remedial action Work Plans that include source zone excavation, dual-phase extraction (DPE), soil vapor extraction (SVE), in-situ chemical oxidation, bio-augmentation, and air sparging techniques. He has provided construction quality assurance (CQA) at landfill facilities, routinely manages Brownfield redevelopment excavation and grading projects, and has worked to assess and remediate releases at various military bases and airports.
Contact Chris at (858) 571-5500 or
Robert Curtis, PE, has more than 30 years of experience designing, permitting, managing, and overseeing construction of civil and environmental projects for both public and private clients. He specializes in creating detailed designs for landfill development and closure, landfill gas collection and conveyance systems, stormwater management and erosion control plans, and management of remedial action projects. He is also experienced in horizontal and vertical expansions, and the closure and remediation of existing facilities. Mr. Curtis has also worked with a variety of waste streams that range from low-strength industrial waste and sludges to municipal solid waste and construction and demolition debris.
Robert Curtis, PE, has more than 30 years of experience designing, permitting, managing, and overseeing construction of civil and environmental projects for both public and private clients. He specializes in creating detailed designs for landfill development and closure, landfill gas collection and conveyance systems, stormwater management and erosion control plans, and management of remedial action projects. He is also experienced in horizontal and vertical expansions, and the closure and remediation of existing facilities. Mr. Curtis has also worked with a variety of waste streams that range from low-strength industrial waste and sludges to municipal solid waste and construction and demolition debris.
Sanam Dahi is a Project Director in SCS’s Energy Division. She has more than 15 years of experience in downstream/upstream of the oil and gas industry, refineries, renewable natural gas, petrochemicals, infra-structure, utilities, water and wastewater treatment industries and safety. She has experience both as a team member and as the head of teams of EPC and front-end engineering (FEED) development on several plants.
Sanam Dahi is a Project Director in SCS’s Energy Division. She has more than 15 years of experience in downstream/upstream of the oil and gas industry, refineries, renewable natural gas, petrochemicals, infra-structure, utilities, water and wastewater treatment industries and safety. She has experience both as a team member and as the head of teams of EPC and front-end engineering (FEED) development on several plants.
Daryl Davis is an Ammonia Refrigeration Advisor for our Tracer Environmental division.
Kim Day is a Senior Project Professional responsible for providing services to over 40 landfills in the areas of groundwater and stormwater monitoring, data evaluation, reporting, permitting, remediation services, and other environmental service projects. She conducts groundwater, environmental assessment, and other environmental study projects for municipal and private clients in several states, including Virginia, Maryland, Massachusetts, New Jersey, North Carolina, Pennsylvania, Rhode Island, and South Carolina.
Kim Day is a Senior Project Professional responsible for providing services to over 40 landfills in the areas of groundwater and stormwater monitoring, data evaluation, reporting, permitting, remediation services, and other environmental service projects. She conducts groundwater, environmental assessment, and other environmental study projects for municipal and private clients in several states, including Virginia, Maryland, Massachusetts, New Jersey, North Carolina, Pennsylvania, Rhode Island, and South Carolina.
Jose de la Lama is a Vice President and Regional Construction Manager for SCS Field Services. He has over 35 years of construction management and leadership experience. He has extensive qualifications in estimating, planning, and delivering civil projects, including landfill gas and landfill gas to energy projects.
Jose de la Lama is a Vice President and Regional Construction Manager for SCS Field Services. He has over 35 years of construction management and leadership experience. He has extensive qualifications in estimating, planning, and delivering civil projects, including landfill gas and landfill gas to energy projects.
Sam Dean is a Senior Project Manager for our Remote Monitoring Control business unit. He has over two decades of experience in solid waste and landfill gas (LFG) management, including remote monitoring, supervisory control and data acquisition (SCADA), control systems, LFG operation and maintenance (O&M) of the landfill gas collection and control systems (GCCS).
Sam Dean is a Senior Project Manager for our Remote Monitoring Control business unit. He has over two decades of experience in solid waste and landfill gas (LFG) management, including remote monitoring, supervisory control and data acquisition (SCADA), control systems, LFG operation and maintenance (O&M) of the landfill gas collection and control systems (GCCS).
Mr. Dean has managed LFG system design, which includes system layout and design calculations, construction specifications preparations, construction management and construction’s quality assurance management (CQA). He has managed wellfield operations services including LFG well monitoring, extraction well balancing and adjustment, blower/flare station data collection and adjustment/maintenance, condensate system/sump maintenance, perimeter probe monitoring, groundwater well monitoring, surface emissions monitoring and non-routine scheduled repairs (leaks, pipe repair, etc.). He has provided maintenance and repairs on extraction pumps, pneumatic condensate sump pumps, thermocouple and electric component replacements.
Mr. Dean has also managed control system projects including design, panel fabrication, programming testing, commissioning and operations support.
Josh DeGayner is a Project Manager with our Sustainable Materials Management division. His experience includes field investigations and project management to support solid waste management and recycling studies as well as other environmental projects.
Stacey Demers is a Vice President of SCS Engineers, a LEED® Accredited Professional, and our National Expert on Solid Waste Composition Studies. She has over three decades experience in the environmental field, specializing in solid waste and energy. Ms. Demers provides strong technical and analytical skills in planning, statistics, sample design for environmental programs, and modeling. Projects include program assessments, data analyses, database management, sampling protocols and associated field sampling specific to sustainability metrics. She is also the director of the Sustainable Materials Management Technical Division of the Solid Waste Association of North America.
Stacey Demers is a Vice President of SCS Engineers, a LEED® Accredited Professional, and our National Expert on Solid Waste Composition Studies. She has over three decades of experience in the environmental field, specializing in solid waste and energy.
Ms. Demers provides strong technical and analytical skills in planning, statistics, sample design for environmental programs, and modeling. Projects include program assessments, data analyses, database management, sampling protocols and associated field sampling specific to sustainability metrics. She is also the director of the Sustainable Materials Management Technical Division of the Solid Waste Association of North America.
Contact Stacey at 571-353-2006 or
Paresh Desai, PE, is a Project Engineer with more than 30 years of engineering experience, including design and permitting of landfill liner systems, stormwater management systems, landfill gas management systems, and landfill gas to energy projects. He also prepares plan approval and Title V permit applications, annual emissions inventory, NSPS and greenhouse gas reporting. He is a Professional Engineer licensed in Pennsylvania, New Jersey, Maryland, and Delaware.
Stephen Descher is a Senior Project Professional with 14 years of solid waste experience, mostly in environmental compliance. He has experience in many aspects of solid waste and environmental compliance, including Title V permitting, monitoring and reporting, data management, groundwater, NPDES and other environmental monitoring, environmental compliance auditing of solid waste facilities, landfill cell construction, landfill cell closure, gas extraction system construction, as well as some experience with ash pond management and closure.
Stephen Descher is a Senior Project Professional with 14 years of solid waste experience, specializing in environmental compliance. He has experience in many aspects of solid waste and environmental compliance, including Title V permitting, monitoring and reporting, data management, groundwater, NPDES and other environmental monitoring, environmental compliance auditing of solid waste facilities, landfill cell construction, landfill cell closure, gas extraction system construction, as well as some experience with ash pond management and closure.
Projects typically have involved permitting, reporting, compliance tracking, regulatory agency liaison, and environmental sampling. Facilities have included landfills, landfill gas control facilities, material recovery facilities, transfer stations, power plants, and various other manufacturing and distribution facilities.
Brett DeVries, PE, PhD, is experienced in a broad range of landfill projects including, permitting, facility design, GCCS expansions, regulatory compliance, research, and construction-related services, including CQA. He is a Registered Professional Engineer in Texas, and has a PhD in Civil Engineering.
Bob Dick, PE, is a Senior Vice President and the Business Unit Director of SCS Engineer’s Mid-Atlantic operations, stretching from Maine to South Carolina. He is also one of our National Experts on Elevated Temperature Landfills. He has over three decades of experience on civil and environmental engineering projects related to solid waste management, and has performed landfill and landfill gas engineering projects (design, permitting, construction, and operations) in more than 15 states and several foreign countries. He is a licensed Professional Engineer in Virginia and North Carolina, a Board Certified Environmental Engineer (BCEE), and a member of the American Academy of Environmental Engineers and Scientists.
Bob is a Senior Vice President and the Business Unit Director of SCS Engineer’s Mid-Atlantic operations, stretching from Maine to South Carolina. He is also one of our National Experts on Elevated Temperature Landfills. He has over three decades of experience on civil and environmental engineering projects related to solid waste management, and has performed landfill and landfill gas engineering projects (design, permitting, construction, and operations) in more than 15 states and several foreign countries. He is a licensed Professional Engineer in Virginia and North Carolina, a Board Certified Environmental Engineer (BCEE), and a member of the American Academy of Environmental Engineers and Scientists.
Bob has also directed and completed numerous project assignments related to solid waste planning and facility projects which have involved residential and commercial collection and recycling programs, as well as convenience centers, composting facilities, and material recovery facility design, permitting, construction, and operations consulting.
Authored several publications and made numerous presentations on air quality, solid waste management, landfill engineering and LFG management/control, design/operations, GHG emissions, composting, and regulatory compliance.
Contact Bob at 804-378-7440 or
Donovan Dickey has experience with an array of environmental compliance and construction quality assurance projects. His environmental consulting experience includes conducting phase I and phase II environmental site assessments; environmental projects involving contamination assessment, remedial system construction, operation of remediation treatment systems; environmental due diligence; pollution prevention; storage tank removal; ground water and soil sampling; landfill gas compliance and performance testing; and surface emissions monitoring.
Donovan Dickey has experience with an array of environmental compliance and construction quality assurance projects. His environmental consulting experience includes conducting phase I and phase II environmental site assessments; environmental projects involving contamination assessment, remedial system construction, operation of remediation treatment systems; environmental due diligence; pollution prevention; storage tank removal; ground water and soil sampling; landfill gas compliance and performance testing; and surface emissions monitoring.
Brent Dieleman is a Project Manager with SCS Engineer’s Sustainable Materials Management Division. He is a certified TRUE Advisor and has two decades of solid waste planning experience, including specialized expertise and experience designing, managing, and directing waste characterization studies and auditing source-separated recyclable materials. Brent’s attention to detail, experience with studies of varying scope and complexities, and his prioritization to understand the client’s goals and objectives put him in a position to manage and execute projects that provide reliable data to inform short- and long-term solid waste planning activities and decisions. Brent uses his certification as a TRUE Advisor and experience to help communities identify and implement policies and programs that put them on a path to significantly expand their waste diversion activities to enhance sustainability and preserve disposal capacity. Brent’s solid waste planning experience also includes collection program evaluation, stakeholder engagement and consensus building, recycling technical assistance, market identification and research, and facility/program/policy feasibility analysis.
Brent Dieleman is a Project Manager with SCS Engineer’s Sustainable Materials Management Division. He is a certified TRUE Advisor and has two decades of solid waste planning experience, including specialized expertise and experience designing, managing, and directing waste characterization studies and auditing source-separated recyclable materials. Brent’s attention to detail, experience with studies of varying scope and complexities, and his prioritization to understand the client’s goals and objectives put him in a position to manage and execute projects that provide reliable data to inform short- and long-term solid waste planning activities and decisions. Brent uses his certification as a TRUE Advisor and experience to help communities identify and implement policies and programs that put them on a path to significantly expand their waste diversion activities to enhance sustainability and preserve disposal capacity. Brent’s solid waste planning experience also includes collection program evaluation, stakeholder engagement and consensus building, recycling technical assistance, market identification and research, and facility/program/policy feasibility analysis.
Daniel Dietch is a Vice President, Project Director, and one of our National Experts on Solid Waste Planning and Recycling. He is responsible for developing the Sustainable Materials Management Practice for SCS’s Southeast Region and works closely with SCS’s national experts to support our regional clients. He has conducted a wide range of solid waste and environmental projects for municipal and private clients. He has a Bachelor’s degree in Geology (with an Archeology minor), and an MBA in Management.
Daniel Dietch is a Vice President, Project Director, and one of our National Experts on Solid Waste Planning and Recycling. He is responsible for developing the Sustainable Materials Management Practice for SCS’s Southeast Region and works closely with SCS’s national experts to support our regional clients. He has conducted a wide range of solid waste and environmental projects for municipal and private clients. He has a Bachelor’s degree in Geology (with an Archeology minor), and an MBA in Management.
Mr. Dietch has more than 20 years of academic and professional experience in solid waste management. He uses this experience to provide clients with strategic solid waste consulting, including solid waste and recycling planning, landfill gas project development, operations monitoring, procurements, litigation support, rate structure/alternative financing analyses, ordinance development, and contract negotiations. His responsibilities include program coordination, planning, execution, and client liaison. Work products include master/strategic plans, landfill closure plans, operations reports, technology reports, rate models and reports, contracts, ordinances, benefit/cost analyses, customized data management systems, and procurement documents.
In addition, Mr. Dietch specializes in developing and managing composting projects. His experience includes on-farm composting, where he has assisted with the development and operation of a turned windrow system, and institutional and municipal composting projects, where he has managed the development and operations of a proprietary in-vessel compost system. For composting projects, he has successfully processed a variety of waste streams, including municipal solid waste, sewage sludge, agricultural, paper and yard wastes, and pre- and post-plate food scraps. In addition to development and management, Mr. Dietch has been responsible for equipment assessment, prototype construction, permitting, and onsite operations.
Contact Daniel at (786) 792-5375 or
Darrin Dillah, PE, PhD, BCEE, is a Senior Vice President of SCS Engineers and heads up our LFG/Engineering Group in SCS’s Reston, Virginia office. His group works on a variety of solid waste engineering design/build projects ranging from biogas/landfill gas and landfills to pump stations, transfer stations, and biogas energy plants. Dr. Dillah has over three decades of experience in the environmental engineering field, including LFG system and landfill design, lecturing and research, feasibility studies, environmental assessments, economic analysis, construction oversight, health and safety implementation, and operation and maintenance.
Dr. Dillah is a Senior Vice President of SCS Engineers and heads up our LFG/Engineering Group in SCS’s Reston, Virginia office. His group works on a variety of solid waste engineering design/build projects ranging from biogas/landfill gas and landfills to pump stations, transfer stations, and biogas energy plants. Dr. Dillah has over three decades of experience in the environmental engineering field, including LFG system and landfill design, lecturing and research, feasibility studies, environmental assessments, economic analysis, construction oversight, health and safety implementation, and operation and maintenance.
Dr. Dillah has also served as an expert witness in his field and as a technical advisor on several international projects, traveling to locations like New Zealand, Nigeria, Argentina, and Mexico.
William Dillon is experienced in the landfill gas (LFG) industry. He is skilled in LFG tuning, troubleshooting, and compliance monitoring on closed and active Title V NSPS subpart WWW, OOO, and XXX sites.
William Dillon is experienced in the landfill gas (LFG) industry. He is responsible for developing streamlined approaches to operations, maintenance, and sampling to maximize cost efficiency and allow competitive pricing strategies for these activities. He is skilled in LFG tuning, troubleshooting, and compliance monitoring on closed and active Title V NSPS subpart WWW, OOO, and XXX sites.
Tony DiPuccio, PE, provides SCS Engineers with a diversified and extensive background in environmental and civil engineering. He has performed both design and study projects in the areas of solid and hazardous waste, wastewater, water supply, and stormwater. Since joining SCS , many of his assignments have been in landfill gas use and management
Mr. DiPuccio provides SCS Engineers with a diversified and extensive background in environmental and civil engineering. He has performed both design and study projects in the areas of solid and hazardous waste, wastewater, water supply, and stormwater. Since joining SCS , many of his assignments have been in landfill gas use and management
Brian Doan, CSP, UST, has been with SCS since 1994. He coordinates and conducts a majority of the field investigations and assessments in the Pacific Northwest. He is licensed for UST site assessments by the Washington State Department of Ecology, and he is certified for UST decommissioning by the International Fire Code Institute.
Brian Doan has been with SCS since 1994. He coordinates and conducts field investigations and assessments in the Pacific Northwest. He is licensed for UST site assessments by the Washington State Department of Ecology, and he is certified for UST decommissioning by the International Fire Code Institute.
Mr. Doan is also SCS’ health and safety officer. He has completed 40 hours of OSHA standard 29 CFR 1910.120 compliant health and safety training with annual eight-hour refresher training. He is also trained in first aid and CPR.
As an EMS auditor, Mr. Doan has been helping clients with ISO 14000 environmental management systems gap analysis and implementation since 1995.
Doug Doerr, PE, is SCS Engineers’ Chief Executive Officer (CEO) as of January 1, 2024. He previously served as a Senior Vice President and the Business Unit Director of SCS Engineers’ Central region. Doug has more than 30 years of professional consulting experience and is one of the founding principals of Aquaterra Environmental Solutions, Inc., which merged with SCS Engineers in 2013. His technical expertise lies in the solid waste management arena and includes all facets of design, permitting, compliance, and economic/financial studies. He has also been involved with many other projects, including air permitting and compliance, traditional civil engineering, alternative energy planning and implementation, and environmental investigation and remediation. His Business Unit has been active in several recent strategic initiatives, including leachate and industrial wastewater treatment and carbon sequestration using underground storage. Doug is a degreed and licensed civil engineer with a BS from the University of Nebraska-Lincoln and an MBA from the University of Kansas.
Doug Doerr, PE, is SCS Engineers’ CEO as of January 1, 2024. He previously served as a Senior Vice President and the Business Unit Director of SCS Engineers’ Central region. Doug has more than 30 years of professional consulting experience and is one of the founding principals of Aquaterra Environmental Solutions, Inc., which merged with SCS Engineers in 2013. His technical expertise lies in the solid waste management arena and includes all facets of design, permitting, compliance, and economic/financial studies. He has also been involved with many other projects, including air permitting and compliance, traditional civil engineering, alternative energy planning and implementation, and environmental investigation and remediation. His Business Unit has been active in several recent strategic initiatives, including leachate and industrial wastewater treatment and carbon sequestration using underground storage. Doug is a degreed and licensed civil engineer with a BS from the University of Nebraska-Lincoln and an MBA from the University of Kansas.
Practice Areas
Doug has directed or conducted numerous projects involving all facets of solid waste management nationwide, including the permitting, design, construction, and compliance of various types of disposal facilities and supporting infrastructure. Projects include feasibility and financial studies, due diligence, facility siting, site investigations, environmental studies, and permitting, design, and construction services for solid waste landfills, industrial waste landfills, utility waste/coal combustion residuals impoundments and landfills, transfer stations, power plants, and various other industrial and commercial facilities. Permitting and compliance efforts have involved solid waste, stormwater, and air permits along with various other environmental and local/regional/state use and zoning requirements.
Contact Doug at (913) 749-0702 or
Stacey Dolden is a Senior Vice President and serves as our Chief People Officer as a member of our executive leadership team. In this role, she leads the Human Resources function and drives the company’s overall people strategy, ensuring alignment with the firm’s mission and growth objectives. Stacey holds a BA in Psychology and an MA in Industrial/Organizational Psychology. She is also a certified Senior Certified Professional with the Society for Human Resource Management (SHRM-SCP®) and a Senior Professional in Human Resources (SPHR®), bringing deep expertise in shaping people-focused strategies that support organizational success.
Stacey Dolden is a Senior Vice President and serves as our Chief People Officer as a member of our executive leadership. In this role, she leads the Human Resources function and drives the company’s overall people strategy, ensuring alignment with the firm’s mission and growth objectives. Stacey holds a BA in Psychology and an MA in Industrial/Organizational Psychology. She is also a certified Senior Certified Professional with the Society for Human Resource Management (SHRM-SCP®) and a Senior Professional in Human Resources (SPHR®), bringing deep expertise in shaping people-focused strategies that support organizational success.
Maura Dougherty specializes in environmental and civil engineering systems planning and design, groundwater hydrology, air pollution modeling, and health risk assessment. She has managed landfill closure cap construction and gas collection and control system (GCCS) construction projects, and has participated in the oversight of project budgets, client interaction, coordination with regulatory staff, design and technical review, and project construction and fieldwork. Ms. Dougherty is a licensed Professional Engineer in California, Oregon, Washington, and Hawaii. She received her Bachelors Degree in Engineering from Princeton University and her Masters in Environmental Engineering from the University of California, Berkeley.
Maura Dougherty specializes in environmental and civil engineering systems planning and design, groundwater hydrology, air pollution modeling, and health risk assessment. She has managed landfill closure cap construction and gas collection and control system (GCCS) construction projects, and has participated in the oversight of project budgets, client interaction, coordination with regulatory staff, design and technical review, and project construction and fieldwork. Ms. Dougherty is a licensed Professional Engineer in California, Oregon, Washington, and Hawaii. She received her Bachelors Degree in Engineering from Princeton University and her Masters in Environmental Engineering from the University of California, Berkeley.
Jason Dreyer is SCS’s Corporate Training and Development Manager, specializing in Health & Safety. He oversees deployment of training programs, including course and curricula development, training staff and supervisors across the country, and developing digital platforms to provide mandatory and supplemental training to employees nationwide.
Jason Dreyer is SCS’s Corporate Training and Development Manager, specializing in Health & Safety. He oversees deployment of training programs, including course and curricula development, training staff and supervisors across the country, and developing digital platforms to provide mandatory and supplemental training to employees nationwide.
