Air Quality Planning and Assessment Research Support Quality Assurance Guidance

The Texas Natural Resources Conservation Commission (TNRCC) works with local planning districts, the Texas Department of Transportation (TxDOT), and others to provide on-road mobile source inventories of air quality pollutants. TxDOT typically funds transportation conformity determinations required under 40 CFR Part 93, while TNRCC typically funds mobile source inventory work in support of Federal Clean Air Act Amendments for attainment of the National Ambient Air Quality Standards (NAAQS) under 42 USCA 7409. The two tasks described in this Work Plan examine alternative inventory development methods and develops a comprehensive list of on-road inventory quality assurance checks. This technical note addresses the second of these, quality assurance guidance. The Eastern Research Group (ERG) has been retained by TNRCC to develop a set of comprehensive analysis tools that will support the needs of various emissions inventories end users. Multiple TNRCC Sections are involved, including Area and Mobile Source Emissions Assessment, Air Modeling and Data Analysis, and Mobile Source Programs. It is essential that all mobile source emissions inventories, prepared by TNRCC staff or by other agencies, be subjected to a rigorous quality assurance check prior to being included in TNRCC's inventory file. Texas Transportation Institute (TTI) staff will develop quality assurance guidance for all onroad mobile source emissions inventories to be added to TNRCC's emissions inventory file.