Air Quality Compliance

As part of efforts to evaluate the potential impacts resulting from new emission sources or modifications to existing sources, the Environmental Protection Agency (EPA) and state agencies may require facility operators to perform air dispersion modeling analyses. Modeling applicability thresholds vary by state and are based on the region’s current air quality; areas with poorer air quality often have lower thresholds, increasing the likelihood that dispersion modeling will be triggered for a proposed project.

Trihydro leverages the EPA’s preferred regulatory model, AERMOD, to support clients through the air dispersion modeling process. AERMOD is a steady-state Gaussian dispersion model grounded in planetary boundary layer theory. It incorporates advanced features, including PRIME building downwash algorithms, local terrain effects, urban heat island impacts, refined meteorological turbulence calculations, and depositional processes. Trihydro offers comprehensive modeling support to help clients navigate regulatory requirements efficiently, including:

• Pre-modeling coordination with regulatory agencies
• Model selection guidance (AERMOD or AERSCREEN)
• Acquisition of land cover, topographic, and meteorological data
• Development of base maps and site layouts
• Model setup and execution using the latest software versions
• Compliance with EPA and state-specific modeling guidance, such as 40 CFR Part 51, Appendix W
• Analysis and interpretation of model outputs
• Coordination with state agencies and model reviewers to create defensible air quality impact documentation

The regulation of industrial wastewater emissions primarily involves the Benzene Waste Operations NESHAP (BWON) (40 CFR Part 61, Subpart FF) and the NSPS for VOC Emissions from Petroleum Refinery Wastewater Systems (40 CFR Part 60, Subpart QQQ). BWON targets benzene emissions from wastewater operations across various industrial sectors based on the total annual benzene generated. Conversely, Subpart QQQ addresses broader VOC emissions from petroleum refinery wastewater systems, triggered by system construction or modification. For petroleum refineries, these regulations frequently overlap, necessitating integrated compliance strategies due to shared emission sources and control measure applicability.

Leveraging over three decades of experience, Trihydro offers comprehensive expertise in both BWON and NSPS Subpart QQQ compliance:

• Compliance, sampling, monitoring, and reporting
• Total Annual Benzene (TAB) reporting
• Compliance assessments
• New Source Performance Standards (NSPS) Subpart QQQ compliance
• Affected waste management unit inventories

The complexity of air permitting can vary significantly depending on the type and location of a facility. For some sites, air permitting is a relatively straightforward process. For others, it involves detailed analysis, technical documentation, and coordination with multiple regulatory agencies.

In addition to managing ongoing compliance with existing permits, facility operators must evaluate air permitting requirements when constructing new facilities, modifying existing operations, renewing permits, or adapting to regulatory changes. Without the proper air permits in place, most projects cannot proceed, making air permitting a critical path item in project planning and execution.

The timeline between submitting an air permit application and receiving final approval can vary significantly, depending on the project scope and regulatory environment. As a result, early identification of air permitting needs is essential to avoid delays and support operational continuity. Trihydro’s permitting team has experience preparing applications to request several different air permits, including:

• New source review (NSR) construction permits for major and minor sources
• Title V operating permits for major sources
• Minor source

The EPA and state agencies require companies to maintain accurate chemical inventories and report quantities of certain chemicals manufactured or imported into the United States. Although these chemical management regulatory programs may have employee safety benefits, they primarily provide information to first responders and the public.

Trihydro’s team of consultants have extensive experience preparing chemical storage inventory documentation. These documents, required by state emergency response planning agencies, assist first responders in an emergency. Additionally, Trihydro has helped many of our clients compile information on the quantity of products manufactured and/or imported to compare with reporting thresholds. If reporting thresholds are exceeded, Trihydro assists clients with preparing reports for submittal to the EPA, documenting the quantities manufactured and/or imported and the environmental releases associated with production. Trihydro has set up user access and prepared electronic report submittals for the following:

• Toxic Substances Control Act (TSCA) Chemical Data Reporting (CDR) due quadrennially
• Toxics Release Inventory (TRI) or Form R reporting (due annually by July 1st)
• Tier II Chemical Inventory reporting (due annually by March 1st)

As part of its efforts to regulate air emissions from industrial facilities, the EPA implemented fenceline monitoring requirements for various industries. These regulations mandate continuous emissions monitoring at the property boundaries of refineries and other industrial facilities that emit hazardous organic pollutants (HAPs).

The EPA’s Refinery Sector Rule, implemented in 2018, requires refineries to monitor benzene emissions at their fenceline. The Hazardous Organic NESHAP (HON) rule also mandates fenceline monitoring for specific facilities, including the synthetic organic chemical manufacturing industry (SOCMI) and Group I & II Polymers and Resins.

Our air experts provide support for our clients’ specific fenceline monitoring needs, including:

• Pilot Study Implementation
• Sample Station Siting
• Compliance Manual Development
• Field Data Collection
• Data Management, Analysis, and Reporting through Fenceline Pro™
• Laboratory Coordination
• Root Cause Analysis and Corrective Action Implementation

In 2009, the EPA established the first federal Mandatory Greenhouse Gas (GHG) Reporting Rule (MRR). Since then, many state and local agencies have implemented or proposed their own mandatory GHG reporting requirements. Under Subpart A of the MRR, facilities subject to reporting must also maintain a current Greenhouse Gas Monitoring Plan, which includes data collection, emissions calculations, and documentation of methodologies.

Maintaining compliance requires more than just submitting emissions reports. Facilities must proactively collect accurate data through field surveys, identify and address data gaps, and implement robust GHG data management plans to meet federal and state regulatory requirements. Trihydro offers comprehensive support for GHG reporting and compliance. Our services include applicability reviews, monitoring plan development, field data collection, emissions calculations, and regulatory reporting.

Our GHG experts specialize in Subpart W of the MRR and provide technical support for:

• Optical gas imaging (OGI) surveys
• Emissions quantification
• Compressor vent measurements
• Transmission storage tank monitoring
• Process controller (Pneumatic) compliance
• Equipment inventories

Trihydro has developed accurate, transparent, and regulation-compliant GHG inventories for clients across a wide range of industries. Our work spans both facility-level and corporate-level inventories and supports compliance with mandatory reporting programs as well as voluntary disclosure initiatives. Each inventory adheres to industry best practices and meets applicable state, federal, and program-specific reporting standards.

LDAR has become an integral part of the day-to-day plant operations at petroleum refineries, chemical plants, natural gas plants, biodiesel plants, and ethanol facilities. Because of the EPA’s enforcement initiatives, attention to fugitive emissions and maintenance of a fully compliant LDAR program is an operational focus.

Our LDAR team has the regulatory knowledge and technical expertise to help clients implement a comprehensive LDAR program that fits facility goals. Trihydro has provided LDAR compliance support to hundreds of facilities, including renewable fuel, ethanol, refineries, natural gas, chemical, and pharmaceutical plants. Trihydro is experienced at preparing audit-ready LDAR programs required under New Source Review (NSR) Consent Decrees and federal and state regulatory programs. We are well-versed in New Source Performance Standards (NSPS) requirements, including various Maximum Achievable Control Technology (MACT) standards and National Emission Standards for Hazardous Air Pollutants (NESHAP) regulations that govern the industries we serve. Trihydro can provide records and database reviews, Method 21 compliance observations, and comparative and shadow monitoring. Third-party LDAR audits and reviews can be scheduled to meet specific regulatory needs and are tailored to meet facility program goals.

Our LDAR services include:

• Program implementation, tagging, and inventory
• LDAR P&ID applicability review and markup
• Routine program monitoring, reporting, and management
• Database management
• Recordkeeping and reporting
• Third-party LDAR compliance auditing
• LDAR program health checks
• Site-specific and general LDAR program training
• Third-party LDAR database quality assurance and quality control support
• LDAR coordinator transition support
• Component counts

Trihydro’s air quality specialists utilize Optical Gas Imaging (OGI) technology to help facilities meet regulatory requirements and improve operational efficiency by detecting and mitigating hydrocarbon gas leaks with speed and accuracy. Our OGI team comprises highly trained and certified thermographers, including senior OGI operators certified under Appendix K, who operate advanced OGI cameras. This expertise allows us to identify and address leaks even when visually obscured by inadequate thermal backgrounds, adverse weather conditions, or other interferences, including difficult-to-detect subsurface leaks. Our team’s training and practical experience produce accurate detections and detailed leak descriptions in complex environments.

OGI is increasingly becoming a preferred technology for demonstrating compliance with air pollution regulations, such as the Best System of Emissions Reduction (BSER) outlined in NSPS OOOOb. This preference is due to OGI’s ability to provide faster, more accurate leak detection, streamlining the monitoring process by eliminating calibration needs and minimizing downtime. OGI enables component-level identification, ensuring no leaks are missed, even in challenging locations, and allows for inspecting unregulated components like flares, vents, and pneumatic controllers. Trihydro’s experts leverage OGI technology to develop comprehensive inspection and repair strategies that optimize costs, enhance safety, and facilitate regulatory compliance, supporting our clients’ specific OGI monitoring needs.

• Greenhouse gas (GHG) Subpart W surveys
• New Source Performance Standards (NSPS) OOOOa, OOOOb, and OOOOc surveys
• BWON no detectable emissions (NDE) equipment surveys
• State regulatory surveys
• Voluntary emissions reduction surveys
• Preemptive facility startup surveys
• Health & safety-based surveys (toxics, H2S, and LEL)
• Internal facility or equipment audit surveys
• Facility turnaround startup monitoring
• Custom surveys to meet requirements of Consent Orders or Decrees
• Flare or combustor destruction efficiency monitoring
• Data management, tracking, and reporting utilizing LeakTracker ProTM