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Along with the rapid development of highways, expressways around environmental issues has also been highlighted, in particular, non-point source runoff pollution is worsening. Due to geographical factors, Chongqing highway in mountainous terrain to build more areas on both sides of highway slope soil is less weathered soil, and humid climate, large and concentrated rainfall, likely to cause slope erosion; Meanwhile, Chongqing higher frequency of acid rain, pH value lower; Additionally, traffic exhaust emissions, fuel and lubricant leakage and car tire friction and other reasons, may make the Chongqing Expressway road runoff pollution is more serious, but the real situation has yet been reported. In this paper, Sea Speed ??(Chongqing Wuhan high-speed) G75, Chongqing beltway G5001 as the research object, select Normal road and floating bridge. In January-September 2009, highway runoff water samples collected during the 10 batches, 55 runoff samples, in which the 2009-04-30 (Spring) ,2009 -06-09 (summer) ,2009 -08-29 ( Autumn) and other three rainfall events were highlighted last sampling. synchronous acquisition by dust and precipitation samples, complemented by indoor simulation of dust dissolution test, explore road runoff pollution emission characteristics and effects of road runoff pollution and external factors, targeted put forward in Chongqing Expressway road runoff pollution control measures and measures for the relevant departments to provide a scientific basis for administrative decisions. The main conclusions are as follows. Chongqing highway runoff monitoring shows that the sample, pH, COD is the normal distribution, the arithmetic mean was 7.63 and 293.16mg / L, while the SS, BOD5, TN, TP, Cu, Zn, Pb, more in line for petroleum lognormal distribution, the geometric mean concentrations of 174.39,2.11,3.17,0.10,0.08,0.59,0.34,1.75 mg / L. To the standard GB8978-1996, using Nemerrow index comprehensive evaluation showed that Wu Yu Chongqing Expressway, reached the beltway moderate pollution, light pollution, the main pollutant followed COD, SS, Pb, petroleum. Chongqing highway runoff pollution compared with domestic research results have been found in Chongqing highway runoff suspended solids concentration is generally lower than other cities; COD and BOD5 concentrations of high concentrations of low biodegradability worse. Chongqing highway runoff pollutants correlation analysis showed that, in addition to Cu correlation with other indicators somewhat less, the other among the indexes were significant or highly significant correlation. BOD5/COD runoff between 0.002 to 0.069, well below the sewage, but also lower than other similar domestic studies, indicating very poor biodegradability. And BOD5/COD with SS concentration has declined, the amount of indirect instructions determines how much road dust polluted runoff control measures. Chongqing highway runoff pollutants principal component analysis showed that the first principal component is reflected in road dust, the second principal component reflects traffic exhaust, the third component is reflected in rainfall. Analysis of variance showed that Chongqing Expressway between ordinary road and the floating bridge, concentration of each pollutant runoff does not reach a significant difference. But between the two highways, COD, BOD 5 , oil and other organic pollutants reach significant difference, indicating the impact of traffic on runoff and vehicle emissions may be settling ground for organic waste. Spring, summer, autumn and winter seasons between the comparison shows that in addition to SS, each index were significantly higher in winter, followed by the degree of contamination of the season for the spring gt; winter gt; summer gt; autumn. Rain water runoff quality and no significant correlation. Chongqing highway pavement dust finer the particle size, the higher the concentration of pollutants contained, pollution is also heavier. Load factor and cumulative load factor showed that about 80% of the pollutants accumulate in the dust particle size below 2.0mm. Simulated acid rain leaching tests showed that the leaching rate of 0.76% of pollutants -15.94% soluble contaminants into runoff is not too much, more is produced with the rain of particulate contaminants. Through the establishment of the early effects of highway road runoff simplified, quantitative models and judgment conditions, identify research areas 2009-04-30,2009-08-29 rainfall events there are some initial effect, the initial effect size was 68.11% and 50.48%, respectively, the initial effect of time was 15min and 25min. While no significant rainfall events 2009-06-09 initial effect. Intercept runoff using 30% of the initial flow rate, can be integrated to remove 69.37? .21% Of runoff pollution load. Subject to conditions, the study sample and sampling frequency setting is not too much, the result needs to be further confirmed. The main contribution of road runoff pollution quantification, highway pavement runoff pollution impact factor effect size, the direction and mode of action such as further study.
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