2026 Look Ahead
Posted: January 14th, 2026
2026 Look Ahead Intro // Colin McCall Happy New Year to all of our readers. We are looking forward to another year of work and camaraderie with our colleagues, clients, and partners. In keeping with tradition, we use our January […]
Read articleLooking Ahead – Fenceline Monitoring
Posted: January 28th, 2025
In 2024, the U.S. Environmental Protection Agency (U.S. EPA) finalized new fenceline monitoring requirements associated with amendments to Standards of Performance for New Stationary Sources (NSPS) and National Emission Standards for Hazardous Air Pollutants (NESHAP) associated […]
Read articleU.S. EPA Finalizes Revisions to Appendix W Modeling Guidelines
Posted: December 19th, 2024
On November 20, 2024, the United States Environmental Protection Agency (U.S. EPA) published the final rule revising 40 CFR Part 51 Appendix W: Guideline on Air Quality Models (Appendix W). Appendix W outlines the U.S. EPA […]
Read articlePhiladelphia’s Air Toxics Regulations in Effect as of January 1, 2024
Posted: June 25th, 2024
The City of Philadelphia’s Air Management Services’ (AMS) new Air Management Regulation (AMR) VI Toxics Rule and health risk screening workbook went into effect January 1, 2024. The AMR VI rule had been finalized at an Air Pollution Control Board […]
Read articlePM2.5 NAAQS Lookahead: Revision of the Annual Standard is Imminent
Posted: January 9th, 2024
Another year has gone by and another lookahead article about potential lowering of the particulate matter less than 2.5 microns (PM2.5) National Ambient Air Quality Standard (NAAQS) is front and center. In last year’s lookahead article I wrote about the […]
Read articleProposed Revisions to the “Guideline on Air Quality Models”
Posted: October 24th, 2023
On October 23, 2023, the United States Environmental Protection Agency (U.S. EPA) published a proposed rule to revise 40 CFR Part 51, Appendix W (the “Guideline on Air Quality Models” or “Guideline”). The proposed revisions include enhancements to the formulation […]
Read articleU.S. EPA releases Draft Cumulative Risk Assessment Guidelines for Planning and Problem Formulation
Posted: August 22nd, 2023
On June 16, 2023, the United States Environmental Protection Agency (U.S. EPA) released a draft document “Cumulative Risk Assessment (CRA) Guidelines for Planning and Problem Formation” that describes the steps for the planning of CRAs and offers guidance for when […]
Read articleIncorporation of Monte Carlo Statistical Simulation Techniques in an Air Dispersion Modeling Analysis
Posted: February 6th, 2023
This article appears in the February 2023 issue of EM Magazine, a copyrighted publication of the Air & Waste Management Association (A&WMA; www.awma.org). Read on A&WMA Speak to an Air Quality Modeling Expert
Read article2023 Air Quality Monitoring Look Ahead
Posted: January 26th, 2023
In our 2022 Air Quality Monitoring Look Ahead, we looked at community organized low-cost monitoring networks, the continued use of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) air quality monitoring, and funding for community partnerships for implementation of […]
Read articleALL4’s Texas 2023 Look Ahead
Posted: January 25th, 2023
The new year is upon us, and ALL4 is looking forward to the changes and challenges it will bring. Whether the concerns are related to air, water, waste, or health and safety, we are here to assist and find solutions […]
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