Air Quality Permitting and Compliance Support

Air Dispersion Modeling

For more than 40 years, Trinity Consultants has performed air dispersion modeling for industrial facilities, utilities, and government agencies. Trinity is recognized nationally and internationally for our skills and advanced modeling software/infrastructure, enabling Trinity to formulate and conduct dispersion modeling studies for numerous applications.    With the implementation of new, state-of-the-science dispersion models, and more companies realizing the value of dispersion modeling as a planning tool to assess the feasibility of major capital projects, optimize operations, and mitigate risk, Trinity provides unparalleled expertise and service for regulatory situations as well as specialized, often technically challenging scenarios:    Assessing impacts of air emissions from a single site or cumulative sites to demonstrate compliance with ambient air quality standards and other air quality-related values (acid deposition, visibility, regional haze, etc.) utilizing U.S. EPA preferred models (e.g., AERMOD) and beta-version AERCOARE (the marine environment version of AERMOD) Assessing impacts of offshore emissions on the air quality of coastal regions using the Offshore and Coastal Dispersion (OCD) model Assessing visible plumes, icing, and fogging impacts due to high water-content air emissions using specialized models such as FOG, SACTI, and CALPUFF  Performing off-site consequence analyses for risk management planning and meeting state and local air toxic modeling requirements using EPA dispersion, fire, and explosion models included in BREEZE Incident Analyst Evaluating individual and cumulative human and ecological risk, and performing probabilistic risk analyses using various modeling tools including BREEZE Risk Analyst and other risk modeling tools Conducting off-site impact and deposition studies to support litigation activities Performing fatal flaw analyses for siting considerations  Predicting the impact of roadway air emissions with MOVES and AERMOD (EPA is proposing to replace CALINE as a preferred roadway model) Conducting regional modeling studies with the Community Multi-scale Air Quality (CMAQ) model and the Comprehensive Air-quality Model with extensions (CAMx, a photochemical model) for regional haze analyses, control strategy evaluations, ozone/PM2.5 impact assessments, and inter-pollutant credit demonstrations in support of nonattainment new source review permitting Conducting odor concentration modeling and predicting the effect of different abatement strategies using SCREEN3, AERSCREEN, AERMOD, and CALPUFF Analyzing potential risks associated with release of liquefied fuel gas (LFG) and liquefied natural gas (LNG) using BREEZE LFG Fire/Risk and Incident Analyst Predicting structural damage and personnel injury from the detonation of high explosives and vapor cloud explosions with BREEZE ExDAM, and illustrating setup and results in powerful 3D graphs and animations  Processing model-ready meteorological data from surface/upper air observations as well as prognostic meso-scale meteorological models (WRF/MM5) to support to various dispersion models (AERMOD, CALPUFF, CMAQ, CAMx, OCD, etc.)    Air Dispersion Modeling Services Trinity provides a wide range of air quality modeling consulting services for regulatory applications, emergency planning, and human health assessments. Regulatory Air Dispersion Modeling Trinity is a global provider of air dispersion modeling, air quality compliance services, and software solutions to regulated air emissions sources of all varieties. Trinity is a leader in the practical use of AERMOD, CALPUFF, and other dispersion models, and has developed numerous tools to aid in identifying subtle anomalies in modeled results that can often be challenged in a regulatory context. Trinity is also the only provider of true high performance computing (HPC) solutions for models such as AERMOD, CALPUFF, and SCIPUFF. Trinity's high performance software solutions and high-speed cluster modeling infrastructure save incalculable computer processing hours, enabling more in-depth analyses and faster project completion. Class I Area PSD Impact and Regional Haze Analyses Trinity has performed numerous Class I area analyses in support of Prevention of Significant Deterioration (PSD) permit applications including PSD Class I Increment and Air Quality Related Value (AQRV) analyses, i.e., visibility and acidic deposition using CALPUFF. In addition, Trinity has completed visibility assessments using VISCREEN and PLUVUE and regional haze analyses for Best Available Retrofit Technology (BART) and Reasonable Progress evaluations in support of the Regional Haze Rule with CMAQ/CAMx. CALPUFF and CAMQ/CAMx modeling requires far more sophisticated analysis than typical near-field models. Because CALPUFF may soon be demoted by EPA as a preferred model, Trinity is increasingly using CMAQ/CAMx for BART and Reasonable Progress evaluations. CAMx has gained favor because of its superior consideration of chemical reactivity as well as other options. We are also versed in the use of SCICHEM, another possible alternative to CALPUFF. Photochemical Grid Modeling The U.S. Environmental Protection Agency (EPA) widely recognizes and routinely utilizes Photochemical Grid Modeling (PGM) for regulatory analysis and attainment demonstrations. PGM simulates the impacts from single and multi-source studies by estimating pollutant concentrations and deposition for chemically reactive pollutants over large spatial scales. Similar regional scale modeling can be performed for inert pollutants as well. Trinity provides comprehensive modeling for both PGM and regional air quality studies by offering such modeling services to our clients nationally and internationally. For more than 10 years, experts at Trinity have been supporting clients with PGM and regional scale modeling services. Learn more>> Multi-Pathway Risk Assessment Dispersion Modeling Trinity has assisted industry, regulatory agencies, and trade associations with technical and modeling support to conduct human health and ecological risk assessments. These projects have included National Environmental Policy Act (NEPA) projects such as coal-gasification plants, MACT residual risk assessments, risk assessments to support RCRA facility permitting for hazardous waste incineration or that utilize hazardous waste derived fuel, and other air quality assessment studies with both inhalation and ingestion pathway assessments. These specialized studies employ a combination of BREEZE AERMOD/ISC, BREEZE Risk Analyst, and other risk modeling tools to account for inhalation and ingestion pathways for maximum exposed individuals and overall population impacts.   Emergency Response Planning and Associated Acute Risks Trinity performs many health effects impact studies for actual and potential releases of toxic and hazardous air pollutants. These studies have included emissions estimations, acute toxicity evaluations for comparison to threshold limit value-based concentration limits, cancer risk assessment, and ambient monitoring studies. Trinity's staff has considerable experience modeling emissions from accidental releases of liquid spills and spills of liquefied gases using dense gas models including DEGADIS, SLAB, ExDAM, VASDIP, and HEXFRAG. Both BREEZE Incident Analyst and BREEZE ExDAM contain a suite of agency-recognized and industry-standard models that can be utilized in various scenarios.  High Performance Computing Solutions Trinity provides true high performance computing (HPC) solutions for models such as AERMOD and CALPUFF. The BREEZE Remote Modeling System (or BRMS), delivers runtimes up to 100 times faster (e.g., 8 hour runs reduced to 5 minutes) than standard desktop computing. The BRMS for AERMOD operates on a massively parallel computer cluster that harnesses the processing power of multiple multi-core computers. Users can submit data online, anytime, and receive email notification when model results are available. The BRMS utilizes the BREEZE AERMOD Parallel Fortran application, which produces identical results to EPA's public air dispersion model. Model Development and Training Since 1983, Trinity has provided market leading PC-based BREEZE® air dispersion modeling software to environmental professionals. Trinity also provides professional training courses in dispersion modeling, taught by senior-level consultants who are dispersion modeling experts. In addition, Trinity develops customized modeling applications and teaches custom courses to meet the needs of individual organizations. Why Choose Trinity In short, there's no better choice for your dispersion modeling needs. Our experience is multi-faceted and extensive. Our strategies are innovative, time saving, and cost-effective. Our staff and tools are the best in the business.


Air Quality Permitting

Whether constructing a new industrial facility, expanding production, or modifying operations, owners and operators may be subject to air quality permitting requirements. Industrial sources must be designed, constructed, and operated to comply with all applicable air quality regulations. Air quality permitting requirements exist within a range of regulatory programs, including state and local codes, and federal programs such as New Source Review and the Title V operating permit program. Each permitting program has associated technical requirements such as emissions quantification, control technology evaluations, air quality analyses (including regulatory dispersion modeling), ambient air and meteorological monitoring, emission standards applicability, and compliance assurance.    Trinity Consultants can assist with all phases of the air permitting process. We have completed thousands of   permitting projects and our experience translates into accurate, timely permit applications that are strategically crafted for maximum flexibility, and expert negotiations with regulatory agencies, streamlining the permitting process.   New Source Review The federal New Source Review (NSR) program requires that new and modified major sources undergo rigorous air quality analyses and receive a permit prior to commencing construction on any physical changes or changes in the method of operation. The analyses must demonstrate the implementation of appropriate pollution control technology and maintenance of air quality standards. NSR is a constantly evolving program, at both the state and federal levels. To determine NSR applicability, Trinity identifies and characterizes emissions from the equipment that comprise the regulated source. Using this information, along with U.S. EPA attainment designations, Trinity performs a thorough regulatory review to determine applicability and requirements of Nonattainment New Source Review (NNSR), Prevention of Significant Deterioration (PSD) regulations, and state construction permitting requirements. Trinity then works with its client to develop a permitting strategy that will enable the project to proceed in a timely manner, while optimizing operational flexibility and minimizing costs. Nonattainment NSR (NNSR) Requirements New or modified major sources in areas designated as nonattainment with National Ambient Air Quality Standards (NAAQS) may be subject to NNSR. If potential emissions from a modification exceed threshold quantities and the facility is a major source of emissions, Trinity’s technical staff will conduct an emissions netting analysis. Emissions netting considers previous emissions changes (within a defined period) at an existing major source to determine if the proposed modification can avoid classification as a major modification. If NNSR is triggered by a project, Trinity will conduct the required Lowest Achievable Emission Rate (LAER) control technology assessment (or the less stringent Best Available Control Technology (BACT) assessment in certain limited circumstances). Other NNSR requirements include locating and purchasing emissions offsets from other permitted sources that have certified emissions reduction credits, as well as demonstrating that the benefits of the project significantly outweigh the environmental and social costs imposed as a result of the chosen location, size, or production processes. In addition to assisting with permitting requirements, Trinity also supports clients with identifying and negotiating the purchase of offsets. Prevention of Significant Deterioration (PSD) New or modified major sources located in areas designated as attainment with NAAQS are subject to PSD review if emissions or net emissions exceed certain threshold quantities. Assessing PSD applicability is a complex undertaking based on volumes of guidance and policy issued by EPA over the program’s history. Trinity’s depth of experience with the PSD program supplies our clients with the nuanced insights needed to develop the optimal permitting strategy. Like NNSR, PSD regulations allow major sources to “net” out of PSD review, should that be practicable. Projects triggering PSD review require a best available control technology (BACT) analysis and extensive air dispersion modeling  that addresses issues such as complex terrain, direction-specific building downwash, and visibility impairment and regional haze impacts in designated Class I areas. As a cornerstone of its technical skill set, Trinity has the specialized expertise to conduct the most challenging dispersion modeling analyses. Obtaining a PSD permit in a timely, cost-efficient manner requires a thorough understanding of the entire PSD program. Our extensive experience with the PSD program helps save clients thousands of dollars in permitting costs and opportunity costs that could result from delays in the start of construction.   Operating Permits   Client Services to Streamline Air Permitting Regulatory applicability analyses Permit strategy development Emissions quantification Emissions netting analyses Permit application development Compliance management tools Compliance certification assistance Control technology evaluations Emissions trading assistance   The Title V program is a federally enforceable operating permit program for significant sources of air emissions, as defined by certain annual threshold levels. Subject sources must submit permit renewal applications every five years to update regulatory applicability and address changes at emission units at the facility. In addition to renewal applications, facilities may also be required to submit Title V permit modification applications if they undertake new construction, make changes in source operations, or become subject to new or existing regulations (e.g., a NESHAP regulation).     In addition to the permit requirements, the Title V program shifted the burden of demonstrating compliance from the regulatory agency to the facility. Compliance demonstration and certification may be a significant undertaking depending on company processes, regulatory requirements, and the efficiency of the company’s recordkeeping and reporting methodologies. Trinity Consultants has prepared more than 850 initial Title V operating permit applications, permit renewal applications, and permit modification applications in all ten EPA regions. Trinity's depth of experience benefits clients in developing Title V permit applications that maximize operational flexibility while assuring monitoring, recordkeeping, and reporting efficiency. Our experience in preparing permit modification applications across all industries allows Trinity to bring unique insight to each engagement and to develop the most beneficial strategies based on client needs.   Trinity built its reputation for excellence on air quality expertise. Air permitting is the foundation of our business and our staff of air quality experts is one of the largest in the country. Our focus on air quality and commitment to ISO 9000-based quality management has resulted in project delivery systems designed to complete jobs on time, accurately, and within budget.   Contact your local Trinity office at (800) 229-6655 for assistance.  


Ambient and Meteorological Monitoring

Trinity's merger with Meteorological Solutions, Inc. (MSI) of Salt Lake City enhanced our ability to provide comprehensive, turnkey meteorological and ambient air quality monitoring services to our clients.    Trinity/MSI's monitoring solutions include the highest quality instrumentation, installed by Trinity/MSI professionals, as well as customized software for data monitoring, retrieval, analysis, reporting, and presentation. Our quality assurance and quality control programs ensure that collected data meet jurisdictional regulatory requirements for completeness, representativeness, precision, and accuracy, achieved by conducting performance and system audits using accepted guidelines and methods.      Our team provides a full range of air quality and meteorological services including: Complete siting services Agency negotiations  Monitoring and quality assurance plan development Equipment installation and calibration Multiple telemetry options including cellular and satellite Automated 24/7 data retrieval every 5 minutes Automated zero span and precision checks Complete data management and validation Official data reporting in state and EPA formats Secure client access to real-time data with extensive plotting and analysis features Iterative modeling site assessment Automated data evaluation and validation  Meteorological towers from 2 meter tripods to 100 meter multi-level towers with solar powered option Continuous monitoring of all criteria pollutants (NO2, ozone, SO2, CO, PM10, PM4.0, PM2.5) Complete data requirements rule (DRR) SO2 monitoring services We are able to assist with the collection of data related to meteorological parameters, criteria pollutants, air toxics, and hydrocarbons. With our 1,200 sq. ft. state-of the art laboratory, we are able to acceptance test and integrate monitoring equipment, conduct site telemetry prior to deployment, and maintain the spare parts needed to keep installations operational.   Our monitoring services are led by technical director Casey Lenhart, Instrumentation and Integration Manager. Casey has nearly 20 years of experience in monitoring site logistics and system development, equipment installation and maintenance, data quality assurance, and agency negotiations. Casey leads a team of specialists who configure, install, calibrate, data process, and quality assure stations across the country. For more information on how Trinity/MSI can assist with your monitoring needs, call (801) 272-3000 or email  


Cap-and-Trade Services

Cap-and-Trade (C&T) programs have become increasingly important in the control and regulation of regional and global air pollutants. In contrast to traditional air pollution regulations, C&T programs require subject facilities to comply with a facility emissions cap that declines on an annual basis, while providing the flexibility to buy and sell excess emission reductions (referred as allowances or credits). Since the 1990 Clean Air Amendments, C&T programs have been used to regulate regional air pollutants, such as volatile organic compounds (VOCs), oxides of nitrogen (NOx), and oxides of sulfur (SOx). In recent years, C&T programs are being used as the primary regulatory vehicle for controlling greenhouse gas (GHG) emissions within the U.S. and internationally.   Where applicable, C&T programs can impact many different types of air pollution sources and industrial sectors, including heavy industry, manufacturing, power, transportation fuels, and utilities. Depending upon the specific rules developed by the regulatory authority, C&T facilities must contend with numerous compliance requirements that far exceed traditional air pollution regulations, which may include:   Declining annual permit limits Industry benchmarking for free credit allowances Daily, monthly and/or annual emissions reporting Quarterly and annual permit reconciliations Buying and selling of emission credits Forecasting future emissions and credit needs Developing air pollution control plans and strategies Continuous Emissions Monitoring (CEMS) Frequent regulatory audits, inspections and testing Independent 3rd party verifications Trinity's multi-disciplined staff provides the highest quality C&T support services that enhance strategic planning and regulatory compliance while maximizing operational flexibility. Trinity helps its clients accomplish this by combining regulatory expertise, technical proficiency, responsiveness, and creative thinking.    Trinity offers strategic advisory and consulting services to prepare and support clients in all phases of C&T regulatory programs, including:  Early stages of rule development Annual reporting and compliance Buying/selling of allowances  Air pollution control plans and compliance forecasting   Trinity regularly monitors the development of C&T programs and actively supports hundreds of regulated facilities throughout the United States and international territories. For more information on Trinity's C&T regulatory services, please contact Charles Lee or Steve Walters at (949) 567-9880.    


Emissions Monitoring Support

Industrial facilities subject to air permits and regulatory emissions limits must frequently implement sophisticated Continuous Emissions Monitoring Systems (CEMS) to demonstrate compliance. Without a solid understanding of the federal regulatory requirements under 40 CFR Parts 60, 63 and 75 (as well as state and local requirements) and the development of a good CEMS program, demonstrating compliance with the applicable requirements can be difficult.    For more than four decades, Trinity Consultants has assisted facilities with air quality permitting and compliance including CEMS related services. Trinity performs CEMS program audits, developing or reviewing existing Parts 60 and 75 Quality Assurance Plans (QAP), and associated permitting. Maintenance of CEMS is an integral part of any QA/QC program and Trinity can assist in creating or updating facility maintenance programs to ensure maximum CEMS data availability and efficient use of existing resources by providing best practice recommendations. We also provide related training courses which detail specific applicable regulations and CEMS maintenance and quality assurance. Trinity's experienced professionals have the expertise to help you ensure a CEMS program that meets your legal obligations and streamlines associated processes.   For assistance, contact Eric Wiley at (949) 567-9880 or  


Emissions Reporting

Emissions Inventories Many air quality permitting projects require a facility-wide inventory of all air emissions sources. An accurate accounting of emissions is also necessary for payment of annual permit fees to state and local regulatory agencies. In addition to common point sources, facilities often have emissions sources that are more difficult to identify and quantify, such as raw material storage piles, material handling operations, solvent cleaning of parts and machinery, surface coating operations, and dust from roadways and parking lots. Use of appropriate emission factors and rates is crucial for developing permitting strategies, determining applicable regulations, and performing air dispersion modeling analyses. Trinity has conducted emissions inventories for thousands of facilities, some with more than 1,000 individual emission points, including fugitive, mobile, point, area, and line sources. We utilize a variety of resources to arrive at the most appropriate emission factor for each source, including information developed by EPA, industry organizations, and equipment manufacturers. Upon completion of the emissions inventory, Trinity compiles the emissions data and corresponding calculations and prepares detailed reports documenting this information. An appropriate tracking and reporting methodology may be as simple as a customized spreadsheet or as sophisticated as a company-wide, fully integrated EHS management information system. Trinity and T3, our EHS technology group, has provided a broad range of emissions data management solutions, consistent with the complexity of the site and the budget of the client. TRI Reporting Reporting of toxic chemical releases is integral to being in compliance, as well as to being a good neighbor and environmental steward, and to enhancing company image. Trinity has conducted chemical release estimates for thousands of facilities, some with complex processes involving complicated chemical reactions and physical manipulations, and dozens of waste streams. We utilize many resources to determine the most appropriate release estimation method for each chemical, including information developed by EPA, industry organizations, and equipment manufacturers. We also develop custom chemical release tracking and reporting tools that are consistent with the complexity of the site and the budget of the client. Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA, or Title III of the Superfund Amendments and Reauthorization Act of 1986) requires submission of the Toxic Chemical Release Inventory (TRI) report every July 1. Trinity assists with TRI reporting by conducting a chemical-by-chemical threshold determination to confirm reporting applicability, and then assembling the required information to develop media by media release estimates for each chemical considering the variables unique to each site/chemical combination. In addition to TRI reports, Trinity also assists clients with Tier II Chemical Inventory reporting, and emergency release notifications required under CERCLA/EPCRA including continuous release reporting. For assistance, contact your local Trinity office at (800) 229-6655.


Emissions Testing

Trinity provides expert consulting services related to emissions measurement, also known as “stack testing.”  Services include:  Forensic analysis of test programs that yield questionable results Design and implementation of test programs Expert witness services related to test program issues Test program management  Assistance with test programs that involve unusual, non-standard emissions units and/or test methods While Trinity does not perform emissions testing in North America, our experts have decades of experience with EPA test methods and with a wide variety of emissions units that require periodic testing.  Trinity also offers professional training courses designed to familiarize environmental professionals with emissions measurement programs, common errors, and effective emissions measurement program management. For assistance, contact Richard Trzupek at (630) 495-1470 or


LDAR Support

Trinity Consultants provides Leak Detection and Repair (LDAR) assistance for the oil and gas, refining, chemical, and petrochemical industries. Trinity is knowledgeable regarding LDAR regulatory requirements and has provided compliance and field support to many facilities nationwide.    Trinity's LDAR experience includes applicability and compliance support for facilities subject to New Source Performance Standards (NSPS), National Emission Standards for Hazardous Air Pollutants (NESHAP), Maximum Achievable Control Technology (MACT) standards, the Resource Conservation and Recovery Act (RCRA), and state specific requirements, including but not limited to: NSPS - 40 CFR 60, Subparts VV, VVa, GGG, GGGa, KKK, and OOOO NESHAP - 40 CFR 61, Subparts F, J, V, and FF MACT - 40 CFR 63, Subparts H, I, S, CC, HH, SS, TT, UU, YY, GGG, MMM, EEEE, FFFF RCRA Subpart BB   Trinity performs gap assessments of facilities' LDAR programs, reviewing them for compliance with applicable requirements. We also facilitate the development and implementation of LDAR programs including the following tasks:  Defining LDAR program and training requirements Acquiring equipment and providing the associated training Implementing monitoring equipment capable of logging data for upload to tracking software Assisting in software selection for long-term program compliance documentation Integration with multiple LDAR databases such as LeakDAS, FEMS, and GuideWare   Trinity also conducts third-party LDAR audits for clients in the chemical and refining industries. Trinity has performed multiple third-party LDAR audits as required by client's Consent Decrees. And, Trinity provides professional training, Compliance Management for Fugitive Emissions & LDAR, as well as custom training on Method 21 and other related topics.     Trinity provides a wide range of assistance related to LDAR, including the following:  Applicability determination Enforcement assistance Response to Section 114 requests Reporting assistance Performing LDAR emission calculations Training (e.g., custom courses) Preparation of written programs   For LDAR assistance, please contact Inaas Darrat at    


NESHAP/MACT and NSPS Compliance

The U.S. EPA has completed its mandated development of the vast majority of the New Source Performance Standards (NSPS) and Emissions Guidelines (EG) in 40 CFR 60 and the National Emissions Standards for Hazardous Air Pollutants (NESHAP) in 40 CFR 61 and 40 CFR 63 (“MACT standards”).  Trinity has tracked these regulations from their genesis in the 1970 Clean Air Act (CAA) and the CAA Amendments of 1977 and 1990. Trinity has an extensive history of providing industry with related compliance assistance such as applicability determinations, compliance plan development, development of testing and monitoring programs, and more.   Additionally, Trinity monitors the ongoing development and promulgation of new NSPS and NESHAP rules. Trinity has partnered with companies and trade organizations to prepare rule development surveys, comment on EPA’s proposals, and analyze the surveyed actual emissions data from which Maximum Achievable Control Technology (MACT) standards are developed. Today, equipment in nearly every facility in the U.S. is affected by one or more NSPS/EG or NESHAP rules. The requirements in these rules are often the first area of consideration in many air permitting studies. With more than four decades of experience in air regulations and permitting, Trinity can be of great value in helping you interpret EPA’s rulemaking information and determine effective compliance solutions for your operations.   For assistance, contact your local Trinity office at (800) 229-6655.  


Photochemical Grid Modeling

The U.S. Environmental Protection Agency (EPA) widely recognizes and routinely utilizes Photochemical Grid Modeling (PGM) for regulatory analysis and attainment demonstrations. PGM simulates the impacts from single and multi-source studies by estimating pollutant concentrations and deposition for chemically reactive pollutants over large spatial scales. Similar regional scale modeling can be performed for inert pollutants as well. Trinity provides comprehensive modeling for both PGM and regional air quality studies by offering such modeling services to our clients nationally and internationally. For more than 10 years, experts at Trinity have been supporting clients with the following PGM and regional scale modeling services.   Photochemical grid modeling: Comprehensive Air Quality Model with extensions (CAMx) and Community Multiscale Air Quality (CMAQ) modeling system Emissions processing: Emission Preprocessing System, version 3 (EPS3), Motor Vehicle Emission Simulator (MOVES), Sparse Matrix Operator Kernel Emissions (SMOKE), and Model of Emissions of Gases and Aerosols from Nature (MEGAN) Meteorological data processing: Weather Research & Forecast (WRF) and 5th Generation Mesoscale Model (MM5) Post Processing and data visualization: Modeled Attainment Test Software (MATS), Visualization Environment for Rich Data Interpretation (VERDI), and ArcGIS Data analysis: Statistical data analysis, Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT), wind rose, and pollution rose Key Application Areas Trinity has utilized PGM in key application areas including, but not limited to, the following:   Single source impact evaluations for Prevention of Significant Deterioration (PSD)  and Federal Energy Regulatory Commission (FERC) permitting Visibility Studies for Regional Haze Best Available Retrofit Technology (BART) and Reasonable Progress (RP) analyses and control strategy evaluations State Implementation Plan (SIP) modeling and planning support Speciated Model Attainment Test (SMAT)Unmonitored Area Analysis (UMAA)Motor Vehicle Emissions Budget (MVEB)Reasonable Further Progress (RFP) Control measure evaluations Precursor contribution and sensitivity demonstrationsReasonably Available Control Technologies and Measures (RACT/RACM)Best Available Control Technologies and Measures (BACT/BACM)Most Stringent Measures (MSM) Source apportionment analyses including Ozone Source Apportionment Technology (OSAT) and Particulate Source Apportionment Technology (PSAT) studies Sensitivity analyses using brute force and Decoupled Direct Method (DDM) Conceptual ozone model Site selection and fatal flaw analyses Inter-Pollutant (IP)/Inter-Basin (IB) credit demonstrations High Performance Computing Solutions Trinity has high performance computing (HPC) clusters that are run using state-of-the-art processors supported by high speed networks and high performance storage. The HPC's computational nodes utilize Intel processors with Linux operating environment. Trinity's HPC clusters can simultaneously run several scenarios of resource intensive PGM that has saved an incalculable number of computer processing hours, enabling more in-depth analyses and faster project completion. Trinity periodically upgrades the clusters to maintain the speed and efficiency in meeting clients needs. Why Choose Trinity Our experience is multi-faceted and extensive.  Our strategies are innovative, time saving, and cost-effective.  Our staff and tools are the second to none, embodying our company's principle in every way to provide environmental solutions delivered uncommonly well.