Geosyntec's air quality practitioners frequently address client challenges with the monitoring of air emissions for the purpose of Clean Air Act compliance in the United States and for similar regulatory programs around the world. We also conduct studies to assess the various components of those emissions and apply the data in the design of innovative solutions for emission control systems and the development of rigorous pollution control programs.

Geosyntec engineers and scientists provide specialized consulting, design, engineering, and regulatory compliance services for new, operating, and retiring facilities and assets. We have developed a number of annual compliance programs that provide comprehensive emission inventory reporting, Title V annual and semi-annual reporting, greenhouse gas reporting, and deviation reporting.

In addition, our practitioners have expertise in New Source Review pre-construction permitting and air dispersion modeling as well as the application of the U.S. Environmental Protection Agency (EPA) air measurement methods. These include the EPA's Standards of Performance for New Stationary Sources, or 40 CFR Part 60, and the Mercury and Air Toxics Standards (MATS).

Our emission measurement experts frequently develop methodologies and configure instruments to monitor pollutants under complex operating conditions, including the application of novel approaches to measure mercury and sulfur trioxide (SO3) emissions. By working closely with our clients and officials from regulatory agencies, we develop test methods and procedures that minimize measurement bias and lead to the collection of high-quality data.

Geosyntec offers installation of state-of-the-practice hardware and software that utilizes cross-duct laser technology for continuous monitoring of ammonia (NH3), and SO3. We also provide Continuous Emission Monitoring System (CEMS) selection and operational assistance, data management, and equipment maintenance to provide maximum equipment up-time and effective data collection and analysis.

Geosyntec scientists have developed specialized continuous real-time measurement methods for certain flue gas constituents important to electric utilities (such as SO3, NH3, and various halogens), in addition to the nitrogen oxide, sulfur dioxide, and other combustion byproducts typically present in flue gas exhaust. In just one example for a power plant in the United States, we applied extractive quantum cascade laser (QCL) absorption spectroscopy to detect sub-ppmv levels of SO3 from multiple points in a selective catalytic reduction exhaust duct. Additionally, statistical calculations were performed to assess exhaust flow variability and possible stratification. The new method achieved favorable detection limits (less than 1 ppmv), and data signal averaging was on the order of 10 seconds per measurement. This enabled real-time monitoring and observation of SO3 changes as sorbent feed rates were varied for optimization at the plant.