Fenceline and Community Monitoring
Monitoring Support for Oil Refineries to Meet Local Regulations
Sonoma Technology is supporting multiple California refineries in addressing local regulations requiring real-time fenceline monitoring and reporting to the public of pollutant concentrations. We are using open-path instrument technology to measure criteria pollutants, methane, black carbon, and toxics. These regulations include the Bay Area Air Quality Management District’s (BAAQMD) Regulation 12, Rule 15 and the South Coast Air Quality Management District’s (SCAQMD) Rule 1180.
To address the rules, our scientists and technicians developed custom monitoring plans to cover each refinery’s fencelines, and installed and maintain all equipment while operating the monitoring networks. We submit the collected data to the refineries and their respective air quality districts. We have also worked with each refinery to develop and maintain data-display websites that provide the public with real-time air quality information.
Ambient Air Quality Monitoring at the Sunshine Canyon Landfill in Los Angeles, California
Sonoma Technology conducts continuous ambient air quality monitoring of particulate matter (PM) and black carbon (BC) pollution and meteorological parameters at the Sunshine Canyon Landfill outside of Los Angeles, California, to quantify the effects of landfill operations on air quality in neighboring communities. Sonoma Technology has worked with the City and County of Los Angeles on this ongoing project since 2007.
To quantitatively estimate the impacts of landfill operations on local air quality, PM and BC concentrations are measured at two monitoring sites that are operated and maintained by Sonoma Technology. Sonoma Technology scientists apply statistical methods to the data to quantitatively estimate the impact of the landfill operations on ambient air quality. We provide the City and County with an internal website that provides automatic, routine display of continuous PM, BC, and meteorological data from both monitoring sites, and Sonoma Technology data scientists review the data daily. Data are validated and reported to the City and County quarterly and annually, and bi-annual meetings between the City, County, our scientists, and the public are conducted to discuss the monitoring program.
Over the lifetime of this project, Sonoma Technology has achieved better than 95% data recovery for the hourly data collected.
Examining Air Pollution and Chronic Respiratory Problems in Children
The Children's Health Study was initiated in 1992 to determine whether long-term exposure to ambient ozone, particulate matter (PM), nitrogen dioxide (NO2), and strong acid vapor is responsible for chronic respiratory problems in children in southern California. It has expanded to include adverse birth outcomes, cardiovascular health effects, and association with traffic-related pollutants.
This multi-year effort involves examining children’s exposure to air pollution in 16 communities located throughout southern California. Sonoma Technology scientists are working collaboratively with researchers at USC’s Keck School of Medicine to perform health exposure assessments for approximately 12,000 study participants. Sonoma Technology staff helped design the study and implement the air monitoring network.
The children's exposure to air pollution is assessed through ambient monitoring, personal sampling, residential monitoring, school-based monitoring, time-activity surveys, housing questionnaires, and exposure modeling. Special analyses include neighborhood-scale modeling of the children's exposure to on-road mobile source emissions. Sonoma Technology is responsible for quality-assuring all exposure-related data used in the study and performing statistical analysis of the temporal and spatial characteristics of ambient pollution levels in the communities.
Health and Environmental Justice (EJ)
Epidemiological Study Investigating Smoke Exposure and Preterm Birth
The increasing frequency and intensity of large wildfire events in recent years have caused major concerns regarding the public health impacts from exposure to wildfire smoke. In this study funded by the NIEHS, Sonoma Technology is working with health scientists at the University of California San Francisco and University of California Berkeley to study the impacts of exposure to smoke from biomass burning on preterm birth (birth at less than 37 weeks of gestation).
Scientists and modelers at Sonoma Technology are investigating the contributions of different types of biomass combustion emissions on exposure to fine particulate matter (PM2.5) and ozone (O3) concentrations in California in 2018, a year with historic levels of fire activity. The types of biomass combustion being studied include wildfires, prescribed fires, agricultural fires, and residential wood combustions. Using the emissions inventories developed in this study and by the U.S. Environmental Protection Agency (EPA), we applied the Community Multiscale Air Quality (CAMQ) model and a brute force method to estimate and assess the contributions of PM2.5 and O3 concentrations from smoke emissions.
In addition, we use daily PM2.5 and O3 concentration outputs from the CMAQ model from EPA to estimate PM2.5 and O3 concentrations attributable to wildfires and prescribed fires for 2007-2018 for each California census tract. We assign and analyze smoke exposures using CALENVIROSCREEN 4.0 census tract demographic attributes, including population, poverty percentile, and ethnicity, and analyze their trends and implications for environmental justice initiatives.
Sonoma Technology and EPA Help Schools Reduce Exposure to Traffic-Related Air Pollution
Nearly 17,000 schools in the United States are located fewer than 1,000 feet from heavily used roads, exposing children to traffic-related air pollutants that are linked to a variety of short- and long-term health effects. Sonoma Technology and our study partner, Arup, worked with the U.S. EPA to develop the Best Practices for Reducing Near-Road Air Pollution Exposure at Schools guidebook. EPA published the first version of the guidebook in 2015 and our updated version in 2021. The 2021 guidebook includes new sections such as air quality monitoring with lower-cost sensors. The publication offers schools strategies to reduce student exposure to traffic-related air pollution.
Strategies identified in the publication are rooted in practical experience and have already been successfully implemented in schools and communities across the country. Best practices covered include:
- Mechanical ventilation and filtration
- Passive and natural ventilation
- Actions that building occupants can take
- School site location and design
- Transportation management policies
- Roadside barriers
The guidebook also provides a mechanical ventilation and filtration system assessment checklist to help schools improve classroom air quality.
As part of our work, we conducted literature reviews on near-road health concerns, mitigation strategies, and best practices for reducing exposure. In addition, we assessed analysis tools to support near-road/smart growth planning and developed case study material illustrating near-road planning principles to reduce pollutant exposure. Final products, all available from EPA’s website, include the guidebook, case studies, a summary infographic, and a list of additional resources to help school officials.
Development of Community in Action: A Comprehensive Guidebook on Air Quality Sensors
As more people across the country are using low-cost sensors to monitor air quality in their communities, air quality agencies are providing information about how to operate these sensors and understand the data collected. Sonoma Technology scientists and public outreach experts helped SCAQMD develop a guidebook on using air quality sensors titled Community in Action: A Comprehensive Educational Toolkit on Air Quality Sensors. The guidebook is part of a toolkit of resources that provides insight on air quality and the sensors used to collect air quality information.
The guidebook includes information and tools for understanding air quality, planning a monitoring project, deploying sensors and collecting data, sharing results, and taking action to improve air quality at the local level. In addition, Sonoma Technology developed three short videos that accompany the guidebook:
Electric Vehicle Fleet Penetration Helps Address Inequalities in Air Quality and Improves Environmental Justice
Accelerating the entry of electric vehicles (EVs) into the on-road fleet could improve air quality and reduce greenhouse gas (GHG) emissions. Despite decades of progress to improve regional air quality, disadvantaged communities near heavily traveled roads and truck routes remain disproportionately impacted by air pollution. Fleet electrification eliminates exhaust emissions, thus offering an opportunity to simultaneously address climate change, regional air quality, and environmental justice in near-road settings.
Sonoma Technology worked with EPRI to assess and illustrate how accelerating the use of EVs could help close the gap in air quality differences between EJ communities and non-EJ locations. The project analyzed the community air quality benefits of alternative EV penetration scenarios for calendar year 2040 and assessed electrification of light-, medium-, and heavy-duty vehicle fleets. Results showed that as the use of EVs increases, air quality differences decrease between EJ and non-EJ areas. Study findings were published in the journal, Communications Earth & Environment.
Roadside Monitoring
Near-Road Air Quality Assessments and Support Services for the Transportation Pooled Fund
From 2014 to 2019, Sonoma Technology assessed near-road air quality, conducted emissions and air quality modeling, and provided near-road support services for a Transportation Pooled Fund (TPF) led by WSDOT. The TPF partnership also included the U.S. Federal Highway Administration (FHWA) and state Departments of Transportation from Arizona, California, Colorado, Ohio, Texas, and Virginia.
Our work for the TPF included developing tools, analyses, and other materials to address near-road requirements. Our peer-reviewed publications discussed our findings on forecasted emissions and measured U.S. near-road air quality. We helped the TPF partnership better understand (1) emissions data in order to identify situations in which traffic will not create air quality problems; (2) modeled vs. measured near-road air quality; (3) the potential air quality benefits of near-road barriers (sound walls and vegetation); and (4) U.S. near-road air quality trends. To support our sponsors, Sonoma Technology also developed an information-exchange website for transportation and air quality planners, and presented research findings at numerous venues, including the U.S. Transportation Research Board Annual Meeting.
A summary of the TPF’s major findings was published by the U.S. Transportation Research Board’s TR News Magazine. TR News Magazine is copyright by the National Academy of Sciences, Engineering, and Medicine; posted with permission of the Transportation Research Board.
Air Quality Support for the State of Colorado
Sonoma Technology has worked with CDOT staff over many years to provide air quality support related to transportation projects. Colorado was one of seven state DOTs that, in collaboration with the U.S. Federal Highway Administration (FHWA), funded Sonoma Technology’s work under a multi-year Near-Road Air Quality Transportation Pooled Fund program.
Sonoma Technology provides ongoing air quality support to CDOT as a subcontracting partner on several CDOT environmental service contracts. An example of our work involves particulate matter (PM) emissions and air quality modeling for the CDOT Interstate 270 (I-270) Corridor Improvements project. For an overview of the I-270 project, see the CDOT presentation available at this webinar link. Government stakeholders for the I-270 improvement project include CDOT, FHWA, and officials in Adams County and Commerce City, Colorado.
To assess the proposed I-270 improvements, Sonoma Technology conducted air quality dispersion modeling and completed a PM hot-spot analysis. We completed PM2.5 and PM10 air quality modeling based on the requirements of (1) the National Environmental Policy Act (NEPA), (2) U.S. EPA guidance for roadway hot-spot analyses, (3) Colorado Revised Statutes (CRS) Section 43-1-128, and (4) CDOT Air Quality Project-Level Analysis Guidance (AQ-PLAG). Our PM analysis work was informed by EPA’s “Transportation Conformity Guidance for Quantitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas.” The analysis was designed to help CDOT address public comments. Therefore, our approach went beyond typical PM hot-spot analyses and assessed PM concentrations at (1) sensitive locations farther than 500 meters from the project, and (2) on public trails within the CDOT right-of-way (ROW). The air quality analysis Sonoma Technology completed is available from CDOT at https://www.codot.gov/projects/i270/project-documents-and-reports; scroll to ‘Air Quality Report’ (our work is included in a Jacobs Engineering pdf file).
Linking Traffic and Distance to Roads with Pollution and Health Effects
For more than 20 years, Sonoma Technology has worked with university and government researchers to evaluate how air pollution affects lung function, respiratory diseases, cardiovascular disease, birth outcomes, and other health outcomes in both children and adults. As a small sampling of the many findings these studies have generated, Sonoma Technology scientists, together with our collaborators, have shown that:
- Pregnant women who resided within approximately 300 m of a freeway either during their last trimester of pregnancy, or at the time they delivered, gave birth to children who were at twice the average risk of being autistic.
- Children who lived within 500 m of a freeway from ages 10 to 18 experienced substantial deficits in lung function development compared to similarly aged children who lived at least 1,500 m from a freeway.
- Living near a freeway is a strong predictor of traffic-related pollution (TRP). Compared with living at least 1500 m from a freeway, living within 250 m of a freeway was associated with up to a 41% increase in TRP in a large urban area, and up to a 75% increase in small urban areas. Thus, traffic strongly affects local air quality in large and small urban areas.
More extensive illustrations of related work are available from our Southern California Children’s Health Study (CHS) information page. Our work with the CHS has shown that pollution exposure at an early age impedes lung development and can lead to lifetime health risks. Many of these studies have examined exposure and health impacts related to near-road air pollution problems.
Air Quality Services
Air Dispersion Modeling to Identify Air Quality Impacts of Construction Projects
Sonoma Technology helped BAAQMD with project-level air quality impact assessments per the California Environmental Quality Act (CEQA), which requires the District to identify and mitigate the environmental impacts of their projects. Sonoma Technology developed dispersion modeling input parameters for several representative construction projects, ran the AERMOD dispersion model to quantify the air quality impacts of the representative projects, and developed screening criteria that help define what construction projects are not required to undertake detailed CEQA analysis.
In addition, Sonoma Technology streamlined the development of AERMOD-ready meteorological inputs using AERMET, a meteorological data preprocessor. Sonoma Technology developed software to acquire and process National Climatic Data Center (NCDC) surface meteorological data sources, automated the processing of precipitation data from the Western Region Climate Center, and developed control AERMET file templates that can be leveraged in future BAAQMD projects.