The use of ambient particulate matter (PM) filter-based sampling to enforce regulatory requirements for facilities operating within the South Coast Air Quality Management District (SCAQMD) is rapidly growing. The SCAQMD has jurisdiction over portions of Los Angeles, Riverside and San Bernardino Counties as well as all of Orange County. Ambient sampling requirements are currently enforced for cement facilities, refineries, lead melters, and for activities involving the movement of contaminated soils. Typically fence line monitoring is required in these instances, or when a source or facility has been identified prior to the implementation of ambient monitors.

Rule 1480 Overview

Proposed rule 1480 would use ambient monitoring for compliance obligations for any facility or operation that has the potential to emit toxic air contaminants, specifically metal toxics. The difference between rule 1480 and other existing rules that utilize ambient monitoring is that rule 1480 will use community input to decide where to place monitors within the community and to identify sources of toxic emissions. The rule is essentially a tool for SCAQMD to identify and regulate facilities who are considered high risk to nearby communities.

How Will Rule 1480 Affect My Facility?

Even if your facility is complying with all SCAQMD rules and regulations, and has already installed the most up to date emission control technologies, you may still be forced to meet additional requirements. They are not just looking for rogue facilities operating out of compliance. Also, and possibly more detrimental, is that your facility, if identified through this rule, will be tagged as “high risk” and thus be under constant scrutiny by the nearby neighbors. Any facility that has the potential to emit toxic metals will be under the microscope including metal scrap facilities, auto body shops, or spray coating operations. Just because there is not a source specific rule for your operations (i.e., cement facilities, refineries, lead melters, and for activities involving the movement of contaminated soils as listed above) this will not shield you from regulation under rule 1480.

PM Sampling Challenges

The use of ambient Particulate Matter (PM) samplers can provide very valuable information if processed correctly, but one must understand the limitations of filter-based sampling methods. These samplers are high volume samplers that collect PM on a filter over a period of time, such as 24 hours. The filter is then analyzed off-site at a lab, typically for toxics such as metals and hexavalent chromium. Data obtained from these filters can provide a qualitative assessment in determining what emissions sources might be nearby.

The problem with filter samples is that they do not provide any insight on time resolution and it is very hard to attribute a nearby source to the PM collected on the filter. Below are some examples of situations where filter samples would provide misleading or insufficient information:

The impact of motor vehicles on ambient PM samplers can cause problems.

• Emissions from motor vehicles is outside the scope of SCAQMD and their rules but that does not prevent their emissions from being deposited onto a sampling filter! If a monitor is located near a facility, with the intent to capture emissions from that facility, the filter may be “contaminated” if mobile traffic is present. For example if a large diesel truck was idling next to the monitor during sampling, it is safe to say that a good portion of those emissions will be deposited onto the filter. Also, based on EPA studies, gasoline and diesel motor vehicles can emit hexavalent chromium, nickel, and arsenic - all toxic metals.

Filter samples average out the concentration over time, so spikes in emissions cannot be addressed.

• If a lead melting facility uses the best available control technology (BACT) for their furnaces it is likely that very little emissions of lead will be released; however, if there was an accidental fire at a nearby home that had walls painted with older lead paint, the filter sample could potentially pick up that lead being emitted from the house fire. If this were to happen it is very likely SCAQMD would conclude that the lead emissions came from the facility. As later described, it will be up to the facility to defend itself that the metals being deposited onto a nearby monitoring station are not coming from their facility.

Source attribution is very tricky for filter samples.

• In a single 24 hour sample, there are numerous sources that can attribute to the PM being sampled on a filter. This makes it very difficult to pinpoint specific stationary sources, especially in an area of high vehicular traffic and numerous emission sources.

High Risk Facility Determination

Recent rule development meetings at SCAQMD have shed some light as to the structure of proposed rule 1480. This rule is designed to address community concerns that may be sparked by ambient air monitoring conducted by SCAQMD by pulling facilities that are identified as potentially high risk facilities into the AB 2588 Air Toxics “Hot Spots” Program. To provide some background into the AB 2588 program – this is a California wide program requiring stationary sources to report their toxic emissions and potentially be required to conduct dispersion monitoring and health risk assessments and to implement risk reduction measures which may include additional control and house-keeping measures.

What Data Does SCAQMD Collect?

Data collected from ambient air monitors will be used by SCAQMD to determine if a facility is considered high risk. In addition to ambient monitoring data, SCAQMD may request specific documents from identified facilities to strengthen the case that the facility under question is high risk. Data collected can include:

• Source Test Data

• Process Data

• Historical Emissions Data

A facility needs to take great caution if it is asked to hand over data to SCAQMD. Once sufficient data has been collected and reviewed, SCAQMD has the power to officially designate a facility as a high risk facility, even though not part of the AB 2588 program.

Refuting a High Risk Facility Determination

If identified as a high risk facility, an opportunity is given to refute that determination. It will be important during this process to provide accurate and representative data that your facility should not be categorized as high risk. Data to be provided should include, but not limited to:

• Production Records

• Safety Data Sheets (SDSs)

• Any required record keeping as stated in your air permits

• Documentation of emission control devices including source tests, if available

• Housekeeping procedures to indicate that you are taking steps to minimize fugitive emissions

A dispersion model showing the transport of particulate matter off-site should also be considered especially if results indicate that off-site dispersion is not directed towards the location of the ambient air monitor.

If the argument is rejected by SCAQMD, your facility will likely be required to:

• Conduct ambient air monitoring in accordance with an approved air monitoring plan;

• Conduct a health risk assessment (HRA); and

• Prepare and implement a Risk Reduction Plan that would reduce the cancer risk below 25 in a million if required by the above mentioned HRA.

How Can KERAMIDA Assist You?

Many of KERAMIDA’S clients in Southern California are in the metals industry and will need to prepare for the upcoming changes in SCAQMD’s air quality regulations. We can provide compliance support for upcoming rule 1480 or any other rule that will require or utilize ambient air sampling. The rule is scheduled to be passed late 2019 so take steps now to ensure that your facility is prepared!

If you have any questions about SCAQMD rule 1480 and how it might impact your operations, please use our quick response form or call us today at (800) 508-8034 to speak to one of our experienced California air quality consultants.

Blog Author

Albert Chung, Ph.D., P.E.
Senior Engineer, EHS Compliance Services
KERAMIDA Inc.

Contact Albert at achung@keramida.com.