Laserfiche WebLink
4.3 AIR QUALITY <br /> 4.3.1 Setting <br /> The following discussion is based in part on an Air Quality Assessment prepared by Illingworth & <br /> Rodkin, Inc in September 2012. This report is attached as Appendix A of this Initial Study. <br /> 4.3.1 Setting <br /> 4.3.1.1 Background Information <br /> Air quality and the amount of a given pollutant in the atmosphere are determined by the amount of a <br /> pollutant released and the atmosphere's ability to transport and dilute the pollutant. The major <br /> determinants of transport and dilution are wind, atmospheric stability,terrain and for photochemical <br /> pollutants, sunshine. <br /> The Bay Area typically has moderate ventilation, frequent inversions that restrict vertical dilution, <br /> and terrain that restricts horizontal dilution. These factors give the Bay Area a relatively high <br /> atmospheric potential for pollution. <br /> The Bay Area Air Quality Management District(BAAQMD) monitors air quality at several locations <br /> within the San Francisco Bay Air Basin. As shown in Table 1,the only violations of State and <br /> Federal standards at the Redwood City monitoring station during the 2009-2011 period were high <br /> levels of ozone and PM2.5� <br /> TABLE 1 <br /> Number of Ambient Air Quality Standards Violations <br /> and Highest Concentrations (2009-2011) <br /> Pollutant Standard Days Exceeding Standard <br /> 2009 2010 2011 <br /> REDWOOD CITY STATION <br /> State 1-hour 0 2 0 <br /> Ozone <br /> Federal8-hour 0 1 0 <br /> Carbon Mono�de Federal 8-hour 0 0 0 <br /> State 8-hour 0 0 0 <br /> Nitrogen Dioxide State 1-hour 0 0 0 <br /> PMz.s Federal24-hour 0 1 1 <br /> Source: Bay Area Management District,Bay Area Air Pollution Summary <br /> The pollutants known to exceed the State and Federal standards in the project area are regional <br /> pollutants. Ozone and PMz.s are all considered regional pollutants because the concentrations are not <br /> determined by proximity to individual sources,but rather show a relative uniformity over a region. <br /> �PM refers to Particulate Matter. Particulate matter is referred to by size(i.e., 10 or 2.5)because the size of <br /> particles is directly linked to their potential for causing health problems. <br /> Kensington Assisted Living Facility Project 18 Initial Study <br /> Redwood City Apri12013 <br />