What’s Happening Now
EPA News
GAQM Update Now Effective – As we mentioned last month, the updated Guideline on Air Quality Models (GAQM) rule package was due to take effect January 28, 2025, but this was to be delayed to March 21, 2025. The rule DID take effect March 21, 2025. See the Federal Register Notice here. Information on the final rule may be found here.
New SO2 Secondary NAAQS – Also, as we mentioned last month, EPA promulgated a revised secondary SO2 National Ambient Air Quality Standard (NAAQS). The secondary NAAQS is designed to protect public welfare. This new standard is 10 ppb (about 26 μg/m3), based on an annual average. The change was published in the Federal Register on December 27, 2024 and can be found here. We know of no other developments at this time. Stay tuned for when EPA releases information about a new Significant Impact Level (SIL), modeling guidance for it, etc.
Conferences and Workshops
2025 TCEQ Environmental Trade Fair and Conference – In 2025, the location of the Texas Commission on Environmental Quality (TCEQ) Environmental Trade Fair and Conference will be in San Antonio, TX on June 3-4, 2025 at the Henry B. Gonzalez Convention Center. Providence will be there and we hope to see you there, too! Come by and visit us at booth 157 in the Exhibit Hall. Click here for more Trade Fair information as it becomes available.
AWMA ACE 2025 – The 2025 Annual Conference and Exhibition (ACE) of the Air & Waste Management Association (AWMA) will be held June 9-12, 2025 at the Raleigh Convention Center in Raleigh, NC.
For more information on ACE 2025, click here.
If your company, organization, agency, State, etc. has an upcoming modeling or air quality-related event (virtual or otherwise) and you’d like it publicized in Providence/Oris Notes, please send that information to us at info@providenceoris.com, and we’ll be happy to include it.
Providence Products
Simply the best!
BEEST Suite
*HOT* BEEST 12.13 is set to come out the first week of April. This new version fixes bugs that were found in BEEST 12.12.
Speaking of BEEST 12.12, we held a double-header webinar back on February 27, 2025 – one for changes to BEEST 12.12 and one specifically discussing the 12.12 changes regarding receptor grids. If you missed them, you can click here to view them.
As always, users in maintenance can download the most recent version of BEEST from https://www.providenceoris.com/software-downloads/.
“Go BEEST Mode !” We still have plenty of Go BEEST Mode t-shirts! You can request one of those by emailing us at info@providenceoris.com.
AerScreen for Windows
AerScreen for Windows 4.05 is coming in April! The update has these new features/enhancements:
- Runs AERMOD 24142
- Runs AERMAP 24142
Users in maintenance can download the most recent version of AerScreen for Windows from https://www.providenceoris.com/software-downloads/.
AERMOD Wizard
AERMOD Wizard 1.09 is out and includes these updates:
- Updated AERMET version to 23132
- Ability to download all of the EPA 2023 ambient monitoring data
- Ability to export Class I areas and Class I area receptors to Google Earth
- Ability to download ASOS data from the new NCEI website
- Inclusion of the 2020 National Emissions Inventory (NEI) data set (and ability to export them to Google Earth)
- And more!
We will include AERMET 24142 and AERSURFACE 24142 in the next release of AERMOD Wizard.
Users in maintenance can download AERMOD Wizard from https://www.providenceoris.com/software-downloads/.
We’re off to use the Wizard!
If you have suggestions for an enhancement to any of our modeling software products, please let us know and we’ll do our best to incorporate it into the software ASAP!
Modeling Tip of the Month
This month, we have not one, but two Modeling Tips for you. Both have important ramifications, so without further ado…
In light of the issues associated with BEEST 12.12, we are revisiting the December 2023 Modeling Tip of the Month. We also discussed this in a YouTube video last month (Bugs in BEEST 12.12 and Workarounds). The issue involves using the current version of AERMOD (24142) in an older version of BEEST. The solution is rather simple:
• Uninstall BEEST 12.12 from your computer and download/install the older BEEST 12.11, which is currently found on the Providence/Oris website. (Software Downloads – Providence Oris) BEEST 12.11 comes with the older AERMOD 23132 installed with it.
• Log on to EPA’S Support Center for Regulatory Air Models (SCRAM) website (Support Center for Regulatory Atmospheric Modeling (SCRAM) | US EPA) and browse to Air Quality Dispersion Modeling | Preferred/Recommended Models. Under AERMOD Modeling System | Model Code, you will find AERMOD executables (zipped) for both 32-bit and 64-bit computers. Download the executable to your computer and unzip it. Place the AERMOD executable into a file path other than C:\Program Files (x86)\Providence\Beest\.
• Open BEEST 12.11 and go to File | Preferences. Click the Model Selection tab. In the field for AERMOD, browse to the folder where you placed the AERMOD 24142 executable and select that aermod.exe and click Open.
Now you have the most recent version of AERMOD in BEEST 12.11. Note that in BEEST 12.13, this will not be necessary.
The second tip of the month can be very important if you process raw meteorological data through AERMET. Currently, if you’re processing raw upper air data (In IGRA format), and if your station’s base elevation is greater than 999 meters, then the upper air EXTRACT or QAOUT file can’t read it, and returns the elevation as a series of asterisks. This, in turn, generates an AERMET E05 error (Invalid option for keyword or invalid variable) in the Stage 2 Messages output file. Therefore, no SFC or PFL output files are generated.
In this example, here’s the AERMET input/control file for Stage 1 processing. For this run, the upper air station is Salt Lake City, Utah. Note the upper air station base elevation of 1289m (in red box):
After running Stage 1 of AERMET, here’s what the upper air EXTRACT file looks like. Note that the upper air base elevation is just a series of asterisks in the red box:
And, here’s the upper air QAOUT file. Again, notice that the upper air station’s base elevation is just asterisks:
While EPA will be fixing this error in the next release of AERMET, they do have a suggested workaround that you can use: Run AERMET Stage 1. After it finishes, open the QAOUT file in Notepad and manually correct the elevation on the LOCATION line in the file and then run Stage 2. AERMET should then finish normally and generate your SFC and PFL output files.
Providence Training
Modeling skills ready for an upgrade? We can help!
We want to note that many folks use our classes as credit toward professional engineer continuing education requirements. Check with your state’s licensing board or the National Society of Professional Engineers (see here or here) for more information on what is required.
**NSR Essentials**
Providence’s next NSR Essentials air permitting class will be May 5, 2025 and it will be online. This class is tailored to those folks who are new to air permitting or perhaps new environmental managers who need a good overview of the basic issues related to air permitting. Topics such as statutes, applicability, netting, emission calculations, and Title V are just some of the areas that are covered. To register for this NSR Essentials class, click here.
AERMOD Modeling for Permits
Our next AERMOD Modeling for Permits class will be May 6-7, 2025 and it will be online. If you are wanting to get started in air modeling, then this class is for you! If you want to register, please click here.
Advanced AERMOD
Similarly, our next Advanced AERMOD class will be May 8-9, 2025, and it will also be online.
Advanced AERMOD covers those topics that are near and dear to modelers, such as:
- NAAQS modeling for 1-hour NO2, 1-hour SO2, and 24-hour PM2.5 (including the new MaxDCont Viewer)
- Meteorological data processing with AERMET/AERMINUTE/AERSURFACE
- Culpability Determination
- Background Concentrations
- Emission scalars and Hourly Emission Rate files
- Changes in Terrain Data Processing
- AERMOD Wizard and its uses
To register for Advanced AERMOD, click here.
Just as a reminder, if you register more than 30 days before your training class(es), you will receive a $100 discount on the course fee (per class, per registrant).
On-demand Meteorological Data Processing webinar
We are planning to launch a new training option – on-demand webinars. The first of these to be released will be “Meteorological Data Processing for AERMOD”. Look for it at www.providenceoris.com coming soon.
On-demand AERSCREEN webinar
We will be releasing an on-demand training webinar for AERSCREEN. Watch this space for details!
Here are our class dates for 2025:
| Dates | Class | Location |
| May 5, 2025 | NSR Essentials | Online |
| May 6-7, 2025 | AERMOD Modeling for Permits | Online |
| May 8-9, 2025 | Advanced AERMOD | Online |
| August 18, 2025 | NSR Essentials | Online |
| August 19-20, 2025 | AERMOD Modeling for Permits | Online |
| August 21-22, 2025 | Advanced AERMOD | Online |
| December 8, 2025 | NSR Essentials | Online |
| December 9-10, 2025 | AERMOD Modeling for Permits | Online |
| December 11-12, 2025 | Advanced AERMOD | Online |
Don’t forget, if our schedule of classes doesn’t mesh with your schedule, or if you have several people that need to be trained at once, contact us about setting up your own onsite or online class.
Providence Services
BeestXpress
**BeestXpress now runs AERMOD 24142**
If you’ve never used our super-fast cloud-based BeestXpress before, now is the time. We have an on-demand webinar that steps you through the process of setting up an BeestXpress account and sending off your first BeestXpress run. You can view the webinar here. New BeestXpress users can complete their first run with up to 50 partitions absolutely FREE. Instructions about receiving the free run are given at the end of the webinar. Beyond the starter run BeestXpress will give you a per-run cost estimate before you begin. If you need help budgeting for BeestXpress, contact us for additional daily rate pricing options.
To date, BeestXpress has processed over 500,000 AERMOD runs.
BeestXpress users can log on at www.beestxpress.com to take advantage of our AERMOD “force multiplier”. That AERMOD run that might have taken a day or two to process on your desktop computer can finish in an hour or less on BeestXpress. When time is money, BeestXpress is the best modeling return on investment there is!
Meteorological Data Processing Services
Do you need AERMOD-ready meteorological data? If so, we can help! Whether it’s running national weather service data or onsite monitor met data through the AERMET/AERMINUTE system, Providence has the background, know-how, and experience to have your data processed and ready for you ASAP. If you’d like more information, contact us at info@providenceoris.com or jamesred@providenceeng.com.
Consulting Solutions
One thing that we’re very proud of is the depth and range of our modeling experience and expertise. The kinds of air quality models we’ve used include all types, ranging from simple screening tools like SCREEN and AERSCREEN to plume models like ISC and AERMOD. The types of analyses include basic Significant Impact Level, NAAQS, PSD increment consumption, Class I analyses, air toxics and SIP attainment demonstrations. So, we’ve seen it all. To that end, should you or your clients need additional modeling assistance or just a second set of eyes to QA or peer review your modeling (ranging from initial protocol up to final submission), we stand ready to help. Feel free to contact us at 512‑258‑8855, 828‑628‑0634 or info@providenceoris.com.
OR . . . maybe you just need advice about a particular project OR you need someone to do a QA review, OR you have a very small modeling task to complete. It would be too much of a hassle to set up a contract for just a few hours of work. What to do?
Easy! Now you can purchase individual air modeling consulting hours with a credit card online through our website! Just contact us first so we’re on the same page about the scope and schedule. Go to https://www.providenceoris.com/product/1-hour-of-expert-air-modeling-consulting/
For clarity, this small-job purchasing option is for air modeling consulting only. Software customers may receive help from us at any time for software-related issues at no cost (this is included in the maintenance fees). Recent trainees may also call to ask us training-related questions at no cost.
Calendar
NSR Essentials
May 5, 2025
Online
AERMOD Modeling for Permits
May 6-7, 2025
Online
Advanced AERMOD
May 8-9, 2025
Online
TCEQ Environmental Trade Fair and Conference
June 3-4, 2025
San Antonio, TX
AWMA ACE 2025
June 9-12, 2025
Raleigh, NC
Our complete class schedule can always be found at https://www.providenceoris.com/training/
For More Information:
Phone: (512) 258-8855
Email: info@providenceoris.com
Visit our websites:
www.providenceoris.com (software, support, and training)
www.beestxpress.com (cloud-based high speed AERMOD)
