South County Particulate Matter Studies & Related Documents
Both the Air Pollution Control District and the OHV Division of State Parks have performed numerous scientific studies to determine the nature, cause and extent of the high particulate matter (PM) concentrations impacting air quality and public health on the Nipomo Mesa. Information about and links to each of those studies is provided below. A summary of the results of each of the major studies described below can be found here.
South County Particulate Matter Efforts
To better understand the steps and process involved over the past 17 years, staff developed a comprehensive flow chart. Click here to view, the chart was last updated in May of 2020 and will be updated again in 2021 to reflect updated steps and measures taken.
South County Phase 1 Particulate Matter Study
An extensive air monitoring study was performed by the APCD from April 2004 through March 2005 to better delineate the nature and extent of the high particulate matter concentrations observed on the Mesa. Comprehensive sampling of both fine (PM2.5) and coarse (PM10) particulate matter was conducted at numerous locations across the Mesa. The results of this study are provided by clicking here.
South County Phase 2 Particulate Matter Study
In February 2010, the Phase 2 Particulate Matter Study was released. Following the release of the Phase 1 Study in March 2007, the APCD Board directed staff to design and conduct a follow-up study with the primary goal of determining if OHV activity on the ODSVRA played a role in the high particulate levels measured on the Nipomo Mesa; a secondary goal of the study was to determine what, if any, particulate impacts on the Mesa are due to fugitive dust from the petroleum coke piles at then ConocoPhillips Refinery complex. To view the entire Phase 2 study, click here. Technical appendices and other documents relative to the Phase 2 study, including the raw data collected during the study, are available here.
South County Community Monitoring Project
The goal of this project was to map the spatial extent and concentration gradient of the ODSVRA dust plume during high wind conditions to better understand its impacts on Nipomo Mesa and Oceano neighborhoods. The data collected was used to develop more detailed air quality forecasts for those areas and enhance the ability of local residents to individually determine if protective actions might be needed on high PM days. The results of this study are detailed in the South County Community Monitoring Project final report, published in January 2013. Technical appendices and other documents relative to the Community Monitoring Project, including the raw data collected during the study, are available here.
State Parks Dunes Dust Studies
The OHMVR Division of the California Department of Parks and Recreation has conducted several studies at the ODSVRA to further evaluate dust impacts, mitigation and air monitoring issues relative to meeting the requirements of APCD Rule 1001. Information about and links to each of those studies is provided below.
2013 Dunes Monitoring Study
OHMVR conducted a comprehensive monitoring study in the spring and summer of 2013 to evaluate potential differences in the emissions and air quality impacts between the riding and non-riding areas of the ODSVRA, and to determine appropriate locations to site air monitoring stations and dust mitigation measures . The results of those studies are detailed in the two documents listed below. The raw data for each of these documents can be obtained by contacting OHMVR.
In 2011, APCD and State Parks jointly funded a study by the Desert Research Institute (DRI) to design and test various dust reduction control strategies at the ODVSRA. Three strategies were evaluated for their effectiveness in reducing dust emissions: enhanced surface roughness, planting vegetation and changing vehicle activity patterns. The results of this study were detailed in the September 2011 publication of the Oceano Dunes Pilot Projects report.
2007 Dunes Vegetation Study
Revegetation is an important dust reduction strategy at the ODSVRA. In 2007, State Parks published a comprehensive study of vegetation coverage within the ODSVRA, including the influence of offroad vehicle activity on dune vegetation. This study, conducted by the California Geological Survey (CGS), provides detailed descriptions of historical and recent revegetation efforts, and recommendations for ensuring future revegetation efforts are successful. The results of this study can be found in an August 2007 CGS report.
Related South County PM Documents
The APCD Rule 1001, Coastal Dunes Dust Control Requirements, requires implementation of dust control measures and air monitoring for coastal dunes where vehicle activity occurs. The Rule, staff report, Board presentation and documents related to implementation of the Rule can be downloaded from the links below:
In addition to the Rule, the APCD and OHMVR entered into a formal agreement that describes how the Rule will be implemented and provides for a formal dispute resolution process between the parties. This Consent Decree Agreement was adopted by the APCD in September 2014.