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David Heitz

Air Pollution Control Evaluations and Performance Assessments

2026-06-30T11:58:58-06:00March 28th, 2014|Tags: , , , , , , , , , , |

Geosyntec's air quality clients need services for emission control, device conceptual design and selection, feasibility, monitoring, evaluation, and optimization for their facilities. We help clients evaluate emission controls under complex regulatory and operational conditions, and we advise them about how to meet emission standards. We also work closely with clients on the selection of air pollution control technologies that minimize operational costs while still meeting the stringent control efficiencies required by federal and local regulations. Selection of optimal control technology includes consideration of the potential for the generation and removal of secondary pollutants such as combustion by-products, reactive compounds, greenhouse gas emissions, or waste or wastewater streams. With expertise in process design, as well as air pollution control technology design, Geosyntec’s engineers develop strategic approaches to complex, multipollutant emission challenges. These challenges are brought about by evolving emission standards on existing equipment and operations, new capital project expansions, facilities, and emission sources. Our portfolio includes finding ways to control gaseous pollutants using methods including scrubbing, adsorption, condensation, catalytic reduction, and oxidation. We also address combustion management and best operating practices for boilers, thermal oxidizers, engines, and combustion devices. In addition, we design particulate filtration, precipitation, and collection systems, dust control approaches, and other ways to control toxic air contaminants. We measure control system performance by applying standard emission measurement protocols, United States Environmental Protection Agency (USEPA) test methods, and other acceptable evolving measurement science to determine compliance or reduction potential for common criteria air pollutants. Our work often addresses emissions of volatile organic compounds (VOC), nitrogen oxides (NOx), carbon monoxide (CO), sulfur dioxide (SO2), and particulate matter, as well as toxic air contaminants and dangerous compounds like mercury and sulfur trioxide (SO3). Geosyntec installs state-of-the-practice hardware and software that uses cross-duct laser technology to continuously monitor ammonia (NH3) and SO3. We help clients select continuous emission monitoring system (CEMS) and programs for CEM compliance with federal state and consent decree monitoring provisions. Additionally, we prepare CEM data quality assurance and quality.

Air Dispersion Modeling

2026-04-21T09:58:39-06:00March 28th, 2014|Tags: , , , , , , , , , , , , |

Under many jurisdictions, facility owners are required to evaluate potential offsite air quality impacts to gain regulatory approvals. Our clients need consultants with experience running air dispersion models. These models use mathematical algorithms to characterize atmospheric processes, to understand how pollutants disperse, and to predict ambient concentrations of air contaminants. Geosyntec applies models to demonstrate compliance with allowable ground-level concentrations established by regulatory agencies. We have experience applying various air dispersion models ranging from those that predict ground-level concentrations from continuous emission sources to consequence analysis models used to assess impacts from unplanned catastrophic events. We use air dispersion modeling to assist clients with regulatory and nonregulatory air modeling projects, including permit applications to address ambient air quality and air toxic requirements. Our team works closely with clients to assess plant layout and stack location configurations to avoid negative impacts on the regional airshed and local communities. In addition, our practitioners conduct modeling to evaluate potential offsite impacts associated with risk assessments and hazard analyses. Our modelers are experienced with AERMOD/AERSURFACE/AERSCREEN/SCREEN3, CALPUFF, ALOHA, SLAB and Computational Fluid Dynamics (CFD) models. Our advanced collection and measurement methods help us generate robust data for air dispersion models that describe the complex behavior of pollutants in the air and how they interact with their environment. Our air dispersion modeling experience includes emerging pollutants such as ethylene oxide (C2H4O) and PFAS. Armed with this data, our engineers and scientists can accurately assess how a source affects a particular area and consult with clients on developing comprehensive environmental management strategies.

Hazardous Air Pollutant Control Program Development and Implementation

2026-06-30T12:03:42-06:00March 28th, 2014|Tags: , , , , , , , , , , , , |

Geosyntec helps clients determine performance and the cost of air pollution control techniques. These techniques are designed to reduce or eliminate emissions of hazardous air pollutants (HAPs) and regulated air toxics from industrial and commercial sources. Our air practitioners offer decades of experience measuring and mitigating adverse environmental and health effects caused by HAPs regulated under the Clean Air Act, the Resource Conservation and Recovery Act, and the Toxic Substances Control Act in the United States. We address client challenges at major and area sources across the country involving air toxics such as benzene, perchloroethylene, methylene chloride, ethylene oxide, and per- and polyfluoroalkyl substances (PFAS). Geosyntec's scientists and engineers employ advanced solutions to identify emission stream characteristics from sources located at a variety of industries. We assist clients with selection and implementation of the best mitigation and control systems for their facilities, and we provide permitting assistance under federal, state, and local air construction and operating permit programs. Geosyntec practitioners specialize in process design and air pollution control technology design that helps us develop strategic approaches to complex, multipollutant emission issues. Our process engineering and air pollution control experts provide clients with a balanced approach to their plant operations.

Landfill Gas Collection and Management Systems

2026-04-21T07:51:36-06:00March 27th, 2014|Tags: , , , , , , , , , , , , , , , , , |

A significant component of Geosyntec's landfill engineering practice is the management of landfill gas and compliance with air quality standards. Our expertise with landfill gas is built upon a legacy of being a recognized leader helping our clients achieve safe, secure containment of regulated wastes since our founding in 1983. Geosyntec has extensive experience in preparing landfill gas collection and control system (GCCS) design master plans for compliance with New Source Performance Standards (NSPS) for several facilities.  We work with facility owners and operators to optimize the construction of landfill GCCS through phased development as cells are constructed and closed. Through proper sequencing, evaluation of future system needs and capacity, and sufficient initial system construction, we take advantage of the installed infrastructure and keep landfill gas flowing as a fuel source. Phased landfill gas management plans benefit our clients by optimizing the value of the capital investment in the gas collection system, minimizing the need to abandon parts of the system as subsequent lifts of waste are placed, and providing reliable gas flows that can generate a steady revenue stream from direct use, power generation, or conversion. We are also assisting our clients in the development of landfill gas-to-energy (GTE) projects, either through self-development or contracts through third parties. Once installed, Geosyntec has the hands-on, practical experience to assist our clients with the operation and maintenance of their GCCS.  Whether it is routine monitoring, tuning and optimization, repairs, or expansions to these systems, Geosyntec can provide the personnel and services to keep a GCCS operating in optimum conditions.  Our field services personnel are familiar with the current practices of landfill operations and have the capabilities to service flares, blowers, compressors, and self-perform repairs on the in-field components such as HDPE piping, valves, wellheads, sumps, and pumps.  Geosyntec is a trusted consultant for compliance issues having successfully obtained permits for landfill gas flares and GTE facilities, including in severe non-attainment areas.  Our professionals develop strategies that allow our clients to manage their air emission portfolios and plan future projects to be compliant with air regulations. We have excellent technical relationships with state and federal regulators throughout the country and are recognized in the industry for our technical leadership. Geosyntec is a dynamic and influential member of the international community of solid waste industry practitioners focused on furthering the science and technology of sound landfill gas management. We are a long-standing member of the International Solid Waste Association (ISWA) with the objective to work in the public interest to promote and develop sustainable and professional waste management practices worldwide. Within the United States, Geosyntec is heavily involved at local and national levels with the Solid Waste Association of North America (SWANA), providing speakers to conferences and serving on national committees for the Landfill Management and Landfill Gas Technical Divisions. As a partner with the U.S. Environmental Protection Agency's (USEPA) Landfill Methane Outreach Program (LMOP), a voluntary assistance and partnership program, Geosyntec works to promote the use of landfill gas as a renewable, green energy source.

Landfill Gas to Energy Systems

2026-04-21T11:04:48-06:00March 27th, 2014|Tags: , , , , , , , , , |

A significant component of Geosyntec's landfill engineering practice is the management of landfill gas and compliance with air quality standards. Our expertise with landfill gas management services is built upon our legacy of being a recognized leader in helping our clients achieve safe, secure containment of regulated wastes since our founding in 1983.

Air Permitting for Landfill Gas Beneficial Reuse Projects

2026-04-06T13:21:34-06:00October 19th, 2009|Tags: |

DeKalb County (DeKalb) wanted to expand its ability to use excess landfill gas (LFG) at its Seminole Road Municipal Solid Waste Landfill for beneficial use. DeKalb desired to: (i) construct a facility that would convert LFG to renewable natural gas (RNG); (ii) add a third engine to an existing Green Energy Facility (GEF) producing electric power through landfill gas-fired reciprocating internal combustion engines; and (iii) install a second flare to increase the capacity to burn LFG when both the GEF and the LFG to RNG were down. Because this facility is located in Atlanta's Nonattainment Area (NA) for ozone emissions, it is considered a New Source Review (NSR) NA major source. Therefore, it may only increase its nitrogen oxides (NOx) and volatile organic compounds (VOCs) emissions by 25 tons every five calendar years. Otherwise, costly and time consuming NSR NA permitting would be required. The site also is a Prevention of Significant Deterioration (PSD) major source for carbon monoxide (CO), and NSR PSD permitting would be required if CO emissions increased by more than 100 tons per year.

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