California-based site remediators and environmental consultants engaging in any earth-moving activities must comply with Rule 1466 regulations. Established by the South Coast Air Quality Management District (SCAQMD), Rule 1466 is designed to minimize fugitive dust emissions, with the overall goal of protecting surrounding communities and sensitive receptors from the harmful effects of poor-quality air.

While SCAQMD is primarily responsible for regulating air pollution across the South Coast Basin (including Orange County, Riverside County, and the Greater Los Angeles area), they are also regarded nationally as a leader in emissions reduction. As a result, Rule 1466 is commonly referenced by agencies outside California, acting as a benchmark for all manner of air quality regulations across the United States.

Rule 1466 compliance can be grouped into three main areas: air monitoring requirements, dust control measures, and general notifications/reporting. In recent years, Rule 1466 has undergone several amendments aimed at further enhancing protections for communities. Updated monitoring requirements include the use of continuous PM₁₀ monitors capable of logging data every 1 minute or less (down from the previous limit of 10 minutes). Site operators must now calculate rolling 2-hour averages and halt all earth-moving activities if PM₁₀ measurements exceed 25 µg/m³.

Required dust control measures include actions like daily stockpile inspections (even on non-operational days), wetting down traffic surfaces, installing adequate fencing, and removing track-out dust using an approved vacuum filter. Site operators are also subject to strict reporting requirements, such as notifying SCAQMD within 72 hours of a PM₁₀ exceedance, tracking wind speed and direction, and maintaining detailed logs in an approved format. In situations where earth-moving activities have the potential to release Volatile Organic Compounds (VOCs) into the airspace, Rule 1166 may also apply.

Aeroqual has helped countless consultants and environmental professionals streamline their Rule 1466 compliance. From our most recent compliance guide to on-demand webinars and air monitoring packages pre-approved by SCAQMD, we’re committed to making it easy for you to maintain compliance and deliver a successful project.