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4.Environmental Analysis — sunlight. Ozone concentrations tend to be higher in the late spring, summer,and fall, when the long sunny days combine with regional subsidence inversions to create conditions conducive to the formation and accumulation of secondary photochemical compounds, like ozone. Carbon Monoxide CO is a non-reactive pollutant that is a product of incomplete combustion and is mostly — associated with motor vehicle traffic,and in wintertime, with wood-burning stoves and fireplaces. High CO concentrations develop primarily during winter when periods of light winds combine with the formation of ground level temperature inversions(typically from the evening through early morning).These conditions result in reduced dispersion of vehicle emissions. Motor vehicles also exhibit increased CO emission rates at low air temperatures.When inhaled at high concentrations,CO combines with hemoglobin in the blood and reduces the oxygen-carrying capacity of the blood.This results in reduced oxygen reaching the brain, heart, and other body tissues. This condition is especially critical for people with cardiovascular diseases,chronic lung _ disease or anemia. Particulate Matter PMio and PM2.5 represent fractions of particulate matter that can be inhaled into the air passages and the lungs and can cause adverse health effects. Particulate matter in the atmosphere results from many kinds of dust-and fume-producing industrial and agricultural operations, fuel combustion, wood burning stoves and fireplaces,and atmospheric photochemical reactions. Some sources of particulate matter, such as demolition and construction activities and mining,are more local in nature, while others, such as vehicular traffic and wood-burning stoves and fireplaces, have a more regional effect. J Very small particles of certain substances(e.g.,sulfates and nitrates)can cause lung damage directly,or can contain adsorbed gases(e.g.,chlorides or ammonium) that may be injurious to health. Particulates also can damage materials and reduce visibility. Dust composed of large particles(diameter greater than 10 microns) settles out rapidly and is easily filtered by human breathing passages. This dust is of concern more as a soiling nuisance than as a health hazard. The remaining fraction,PMIo and PM2.5, are a health concern particularly at levels above the federal and state ambient air quality standards. PM2.5 (including diesel exhaust particles) is thought to have greater effects on health, because these particles are so small and thus are able to penetrate to the deepest parts of the lungs. Scientific studies have suggested links between exposure to fine particulate matter and numerous health problems including asthma, bronchitis, acute and chronic respiratory symptoms such as shortness of breath and painful breathing. Children are more susceptible to the health risks of PM2.5 because their immune and respiratory systems are still developing. In 1983, CARB replaced the standard for"suspended particulate matter"with a standard for suspended PMto or`respirable particulate matter." This standard was set at 50 micrograms per cubic meter(pg/m)for a 24-hour average and 30 pg/m'for an annual average. CARB revised the RMC Pacific Vernalis Quarry Mining and Reclamation Project ESA/203015 Draft Environmental Impact Report May 2006