Arkansas Ambient Air Monitoring Network: Annual Network Plan for 2024-2025

The Arkansas Department of Energy and Environment – Division of Environmental Quality (“DEQ”) submitted on July 1st to the United States Environmental Protection Agency (“EPA”) a document titled:

Arkansas Ambient Air Monitoring Network – Annual Network Plan for 2024-2025 (“Plan”).

The Plan was prepared by DEQ’s Office of Air Quality.

DEQ describes the Plan as providing:

…the framework for the establishment and maintenance of the statewide Air Quality Surveillance (“AQS”) System.

The sampling of ambient air conditions is an important part of the process for determining whether an area is/or will remain in compliance with the Clean Air Act National Ambient Air Quality Standards (“NAAQS”).  EPA uses Clean Air Act authorities to require state and local monitoring agencies to establish a network of air monitoring stations. They use siting and operational criteria established by the federal agency to determine compliance with NAAQS. Further, EPA requires state and local agencies to conduct an assessment of their monitoring networks periodically.

Note that the states are primarily responsible for ensuring attainment and maintenance of each NAAQS in its air quality control regions once the EPA has established or revised them. Each state is then required to formulate, subject to EPA approval, an Implementation Plan (i.e., “SIP”) designed to achieve each NAAQS. The ability to demonstrate that the state has the ability to adequately sample and monitor for each NAAQS is required to be demonstrated by the state.

EPA has previously stated that the three primary objectives of such monitoring networks include:

• Ensuring the public has access to clean air by comparing data and implementation of the NAAQS and other health indicators for toxics.
• To provide the public with timely reports and forecasts of the Air Quality Index.
• To provide information to health and atmospheric scientists to better inform future reviews and revisions to the NAAQS.

Arkansas and the other states’ monitoring network plans describe which pollutants and other parameters are used at the various ambient air monitoring sites and why they are measured at those specific locations. Also typically described are changes in the network which many include new locations along with new and discontinued measurements at existing locations. Proposed changes in the network in the near future are also often addressed.

Besides the figures and tables, the 2024-2025 Arkansas Plan components include:

• Arkansas ambient air monitoring network.
  • Ozone monitoring network.
  • Particulate matter monitoring network.
    • Fine particulate matter (PM2.5) network.
    • Coarse particulate matter (PM10) network.
    • PM10-2.5 particle mass.
    • PM2.5 speciation.
  • Sulfur dioxide monitoring network.
  • Carbon monoxide monitoring network.
  • Lead network/lead waivers.
  • Entergy Independence Plant.
  • Entergy White Bluff Plant.
• Contact information.

A copy of the Plan can be downloaded here.