California Air Resources Board (CARB) staff have developed this frequently asked questions (FAQ) document to address and provide context to feedback received in summer 2022 on the SNAPS Draft Inglewood Oil Field (IOF) Communities Air Monitoring Plan (https://ww2.arb.ca.gov/sites/default/files/2022-06/SNAPS_IOF communities_Draft_Air_Monitoring_Plan.pdf).

Given delays in the schedule, will CARB staff conduct mobile monitoring around the IOF prior to the start of stationary monitoring?

At the request of the community, CARB staff (staff) plan to collect preliminary mobile monitoring data prior to the start of stationary monitoring on surface streets in the area surrounding the Inglewood Oil Field. Staff will evaluate collected data for any elevated pollutant concentrations. Driving routes for additional mobile monitoring can be modified based on initial results. Based on initial suggestions from community stakeholders, streets bisecting Fairfax Ave and the intersection of La Brea Ave and Northridge Dr will be included in initial mobile monitoring routes. The first of such routes occurred the week of September 26, 2022. Additional mobile monitoring may be planned based on the timing of stationary trailer deployment.

Will staff be able to respond in real time to odor complaints through mobile monitoring?

No, staff are not available 24/7 in the areas surrounding the IOF and are not able to use mobile monitoring to respond to odor complaints in real-time. The primary goal of SNAPS is to characterize air quality in communities near oil and gas operations. The investigation of odor complaints is outside the scope of SNAPS. However, odor complaints will inform mobile monitoring routes and times (e.g., staff can alter mobile monitoring times and routes based on occurrence of odor complaints. For example, if numerous odor complaints occur around 6 AM, staff will aim to do more mobile monitoring in the early morning). To this end, odor complaints may be reported to our phone line (to be posted once stationary monitoring begins), or by email (mailto:SNAPS@arb.ca.gov).

Based on the prevailing wind directions and increased risk, should mobile monitoring be concentrated in the communities east of the IOF?

Mobile monitoring routes will be designed to incorporate this concern. Mobile monitoring data will not be limited to the proposed fixed locations, as data will also be collected as staff drive the vehicle through streets in communities around the IOF. The suggested sites in the Community Air Monitoring Plan are based on the 2019 MRS Health Risk Assessment. Staff plan to use initial collected data as well as feedback from the IOF communities to refine mobile monitoring routes. However, staff will continue to consider mobile monitoring routes elsewhere around the oil field since pollutants might disperse to the south, west, and north sides of the IOF in the evening and early morning when meteorological conditions tend be more stable.

Will staff coordinate with relevant agencies during the SNAPS monitoring period?

Yes. Staff have been in discussions with South Coast Air Quality Management District staff (including South LA AB 617 staff and Community Steering Committee co-leads) regarding monitoring efforts and will continue to discuss leveraging resources to determine the best way to monitor air quality near the IOF. Staff have also been meeting with LA County Department of Public Health and UCLA monthly to coordinate the Baldwin Hills Health Assessment with SNAPS and will continue discussions with the Baldwin Hills Community Advisory Panel (CAP). CARB values the feedback received from CAP members and the IOF communities and are considering recent suggestions, including having in-person meetings once we begin SNAPS monitoring.

When will the 1-year period of stationary monitoring begin?

CARB plans to locate two stationary monitoring trailers for approximately 12 months near the IOF before the end of 2022. One trailer will be located at Marycrest Manor (west of the IOF) and one on the eastern edge of the IOF near Kenneth Hahn State Recreation Area. However, the timeline needs to be flexible to accommodate staff preparation and contract implementation, with possible delays into early 2023.

Could there be more stationary monitoring sites if there was a larger budget for SNAPS?

CARB does not currently plan to increase the resources dedicated to monitoring in this community. The two stationary monitoring sites were chosen with the expectation that they will provide robust data to characterize air quality near the IOF. Specifically, these sites were chosen to allow measurements both upwind and downwind of the IOF based on the predominate wind directions. These locations have the potential to capture emissions from the oil field, with one site on the eastern edge of the IOF and the other just west of the IOF and have the potential to also capture emissions from other sources (e.g., mobile sources). While additional funding might provide resources for additional staff and monitoring equipment, additional resources don’t necessarily result in an improved air monitoring plan and may not result in additional useful information. Adding funding to this program, if available, would also take substantial time, further delaying SNAPS air quality monitoring near the IOF, and potentially delaying air monitoring in subsequent communities. 

Will CARB deploy low-cost VOC sensors in the community as part of SNAPS monitoring?

The SNAPS team is currently procuring 10 low-cost VOC sensors for field deployment. Once acquired, we will work with the community to explore how to best deploy these low-cost VOC sensors, examine the data quality of commercially available sensors, and learn how the data can assist in achieving the SNAPS program’s monitoring objectives. Typical low-cost VOC sensors are bulk measurements and do not have the capability to measure speciated (specific) VOCs. These bulk measurements are good qualitative measures of the VOCs present at a given time but may not be useful in identifying individual odor compounds or health risk. However, low-cost VOC sensors can be used to help inform future mobile monitoring routes and timing.

How will staff ensure the integrity of monitoring at the site on the oil field?

Security measures such as locked monitoring instrumentation and security fencing will be taken to ensure data integrity. CARB cannot control oil field activity during the monitoring period. Staff will monitor IOF production and workover data during monitoring and while performing data analysis to evaluate if major changes to production activities have occurred or impacted pollutant concentrations. Additionally, the Marycrest Manor monitoring site is located downwind of the IOF when the wind shifts to the offshore direction (i.e., overnight and during Santa Ana winds). This data can be compared with the SPR site data to screen potential emission anomalies.

Does CARB plan to share the data publicly?

Our goal is to analyze the data and post a draft final report within approximately one year of the completion of air monitoring. A complete data set, however, will not be released until public comments have been incorporated into the draft. A subset of state and federal criteria pollutants (PM_2.5, ozone, carbon monoxide, and hydrogen sulfide) as well as a few other pollutants that are measured in real-time, such as methane and black carbon, will also be displayed in real-time on our website once monitoring starts.

How will CARB respond if high concentrations are observed?

If concerning concentrations are observed at the monitoring trailers, we will work with emergency management, the operators, and the Air District to address any detected leaks. We will also notify the community through the SNAPS website (https://ww2.arb.ca.gov/our-work/programs/study-neighborhood-air-near-petroleum-sources) as well as established networks, such as the Baldwin Hills Community Advisory Panel (CAP) listserv and/or SPR notification system.

Will concentrations measured via SNAPS air monitoring be compared to health standards?

The health risk assessment (HRA), included in the final report for the SNAPS IOF Communities, consists of two parts – a cancer and noncancer risk assessment. The noncancer assessment will be conducted using acute (short-term) and chronic (long-term) health guidance values (HGVs) that indicate how toxic a compound is and the types of health effects it could potentially produce. HGVs (cancer and noncancer) established by OEHHA and other agencies will be used to estimate risks. In addition to the HRA, air concentrations of criteria pollutants and hydrogen sulfide will be compared to California Ambient Air Quality Standards where available; otherwise, Primary (health-based) National Ambient Air Quality Standards will be used.

Will CARB perform any modeling that considers the terrain of the IOF, close residential proximity at lower elevations to the IOF, and overnight odor complaints when winds are calm?

The SNAPS team has initiated conversations with CARB modeling staff to assist in conducting modeling with data collected near the IOF, noting that the potential for future modeling is highly dependent on which compounds are detected and consistency of the data. This potential modeling would use high-resolution spatial data to account for the complex terrain on and around the IOF, knowing that the topography can easily influence pollutant dispersion. The SNAPS trailers will also be equipped with their own meteorological stations that can capture some of these smaller scale variations in wind speed and direction.

What are the methodologies for separating out emission contributions from traffic and other emissions from those emitted only from the IOF?

We have a contract in place to perform source apportionment analysis. The vendor will use Positive Matrix Factorization (PMF) to analyze the VOC data (including benzene, toluene, ethylbenzene, and xylenes (BTEX)) collected using online gas chromatography (GC) systems. PMF analysis has the ability to categorize measured pollutant concentrations into different factors which can be related to emissions from sources, or source types (e.g., mobile sources vs oil and gas-related sources). Our selection of PMF analysis is based on time resolution of measurements and the source attribution guidance (https://ww2.arb.ca.gov/capp-resource-center/community-assessment-tools/source-attribution) provided by the CARB Office of Community Air Protection. Efforts to model emissions using PMF as part of this project will adhere to this guidance.