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Community Air Risk Evaluation (CARE) Program |
The Community Air Risk Evaluation (CARE) program was initiated in 2004 to evaluate and reduce health risks associated with exposures to outdoor toxic air contaminants (TACs) in the Bay Area. The program examines TAC emissions from point sources, area sources and on-road and off-road mobile sources with an emphasis on diesel exhaust, which is a major contributor to airborne health risk in California. The main objectives of the program are to:
How will BAAQMD achieve these objectives? The CARE program is an on-going program that encourages community involvement and input. The technical analysis portion of the CARE program is being implemented in three phases that includes an assessment of the sources of TAC emissions, modeling and measurement programs to estimate concentrations of TAC, and an assessment of exposures and health risks. Throughout the program, information derived from the technical analyses will be used to focus emission reduction measures in areas with high TAC exposures and high density of sensitive populations. To assist the District in guiding this program, CARE Task Force members that include representatives from the community, industry, health departments, and research institutions meet on an as-needed basis to receive updates, discuss and review recent findings, and provide input on program direction. Agendas and presentations from past Task Force meetings are available. Phase I
When the TAC emissions are weighted by toxicity, one can estimate which compounds and which sources pose the greatest risk. The results of the Phase I analysis indicate that diesel particulate matter (diesel PM) accounts for over 80% of the cancer risk weighted TAC emissions (Figure 4a) and that on-road and off-road mobile sources are responsible for the majority of cancer risk from air toxics (Figure 4b). The California Air Resources Board identified diesel PM as a toxic air contaminant based on its potential to cause cancer and other health problems, including respiratory illnesses, and increased risk of heart disese and even premature death. Exposure to diesel PM is a health hazard, particularly to children and elderly. Diesel PM consists of primarily fine particulates that are produced from the combustion of diesel fuel from on-road and off-road heavy duty diesel trucks and construction equipment. Phase I was completed in Fall 2006. A copy of the Phase I Findings and Recommendations Document is available.
Phase II In Phase II of the CARE program, the District is performing regional-scale and local-scale modeling to determine the significant sources of diesel PM and TAC emissions locally in the priority communities as well as for the entire Bay Area. In an example of local-scale modeling, the District partnered with the California Air Resources Board (CARB), Port of Oakland, and the Union Pacific Railroad to estimate the health risks from diesel exhaust in West Oakland. Draft results of the comprehensive Health Risk Assessment (HRA) were made available in March 2008 and take into account emissions generated from:
The study determined that the West Oakland community is exposed to diesel PM ambient concentrations that are almost three times higher than the average background diesel PM in the Bay Area. The estimated lifetime potential cancer risk for residents of West Oakland from exposure to diesel PM is about 1,200 excess cancers per million over a 70 year lifespan. On-road heavy-duty trucks result in the largest contribution to the overall potential cancer risk levels in the West Oakland community, followed by ships, harbor craft, locomotives, and cargo handling equipment. CARB has adopted numerous regulations to reduce diesel PM emissions and expects to adopt additional rules. These rules will significantly reduce cancer and noncancer risk in West Oakland and other communities affected by diesel PM. The fact sheet, draft summary (March 2008) and most appendices are available now and a final report is scheduled to be released in June 2008. Even with the adoption of CARB's proposed regulations, the District is committed to further reducing diesel PM in the Bay Area beyond those measures prescribed by CARB. To achieve this objective, the District developed a mitigation action plan that involves the communities and businesses to seek grant funding for diesel emission reduction projects and offers decision-based tools to assess potential health risks associated with proposed land use projects. Additional Phase II Studies The health risk assessment results show that residents of West Oakland are exposed to unhealthful levels of diesel PM. The District is undertaking several studies to reduce the uncertainties in the truck estimates and enhance the District's understanding of cargo transport throughout the West Oakland community in order to implement the most effective mitigation strategy. West Oakland Truck Traffic Survey
Mobile Sampling Van Look for the District in your community. The District is currently working on a mobile sampling van that will be instrumental in assessing the air quality in the Bay Area from temporary events to long term construction projects. The van will also be used to assess local air quality and compare it to the District's existing toxic monitoring network. Phase III In Phase III, the District plans to conduct an extensive exposure assessment to identify and rank the communities as to their potential TAC exposures and determine the types of activities that places them at highest risk. The District will also pursue additional mitigation measures and provide a metric to assess their effectiveness in reducing overall exposures.
Links California Air Resources Board Community Health page Pacific Institute's Report on the West Oakland Environmental Indicators Project
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