Construction and Remediation Sites Must Comply with New Air Quality Regulations - SCAQMD Adopted Rule 1466

The South Coast Air Quality Management District (SCAQMD) recently adopted new Rule 1466, Control of Particulate Emissions from Soils with Toxic Air Contaminants (TACs). The purpose of the new rule is to regulate particulate emissions resulting from earth-moving activities at sites contaminated with metals and certain other TACs. Specifically, adopted Rule 1466 would apply to sites where one or more Applicable TACs, arsenic, asbestos, cadmium, hexavalent chromium, lead, mercury, nickel, and polychlorinated biphenyls (PCBs), have been identified as contaminants of concern based on concentration thresholds by one or more of the following agencies:

• United States Environmental Protection Agency (USEPA)
• California Department of Toxic Substances Control (DTSC)
• California State Water Resources Control Board (SWRCB)
• Any of the California Regional Water Quality Control Boards (RWQBs)
• SCAQMD

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Projects and facilities subject to adopted Rule 1466 would be required to perform continuous monitoring for particulate matter with aerodynamic diameter of ten microns or less (PM10) during earth-moving activities, implement dust control measures, and notify SCAQMD of subject earth-moving activities.

Continuous PM10 Monitoring

Under Adopted Rule 1466, continuous ambient PM10 monitoring would be required at one or more upwind location and one or more downwind location. If the activities’ PM10 contribution (downwind concentration minus upwind concentration) exceeds 25 micrograms per meter cubed (µg/m3) averaged over one hour, the owner/operator must cease earth-moving activities and implement additional dust control measures. Earth-moving operations cannot be reinitiated until the PM contribution drops below 25 µg/m3 averaged over 30 minutes.

Dust Control Measures:

Dust control measures that would be required under Rule 1466 include, but are not limited to:

• Six-foot tall perimeter fencing with a porosity of 50% plus or minus 5%. In addition, the fence must be at least as tall as the height of the tallest stockpile contaminated with Applicable TACs;
• Use of watering to prevent visible emissions;
• Stoppage of all operations if average wind speed exceeds 15 miles per hour (mph) or gusts exceed 25 mph;
• A SCAQMD certified Dust Control Supervisor onsite;
• Vehicle dust control measures (speed limits, soil stabilization, etc.);
• Contaminated stockpile dust control measures (dust suppressant, covering, height and volume restrictions, etc.);
• Truck loading dust control measures (watering, six inches of freeboard during transport, etc.)

Additional measures would be required for projects located at a school, early education center, or joint use agreement property.   

Notification Requirements:

Under Adopted Rule 1146, project/facility owners or operators would be required to notify SCAQMD at least 72 hours and no more than 30 days prior to earth-moving activities.  In addition, owners/operators must email a notification to SCAQMD within 72 hours of an exceedance of the PM10 concentration limit discussed above.

In addition, to notifying SCAQMD, owners or operators would be required to maintain signage according to the following requirements:

• Signs must be installed at all entrances and at intervals of 1,000 feet or less along the property line or perimeter of the site, with a minimum of one along each side
• Signs must be posted between six and eight feet above grade
• Signs must measure at least 48 inches wide by 48 inches tall
• Sign lettering must contrast with the sign background and measure at least four inches tall.

Failure to comply with Rule 1466 can result in citations and fines. The rule is expected to be finalized and adopted within the near future, so facility and project managers should be wary of all planned and potential earth-moving activities. In addition to Rule 1466, accounting for the TACs is an important component for the project’s Storm Water Pollution Prevention Plan (SWPPP) requirements. Any project disturbing one acre or more of land must prepare a SWPPP and file for a Storm Water Discharge Permit form the CA State Water Board. A qualified SWPPP Developer (QSD) must prepare the SWPPP and the project must be overseen by a Qualified SWPPP Practitioner (QSP). Contact Alta Environmental at info@altaenviron.com or (800) 777-0605 for further information regarding applicability and compliance with Proposed Rule 1466 and/or SWPPP requirements.