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EXHIBIT 2 <br /> A=COM <br /> 3.7.1 RAIL AT-GRADE CROSSING IMPACT CRITERIA <br /> In order to analyze existing and future vehicle delay at the Santa Ana Boulevard at-grade <br /> rail crossing, a spreadsheet model was created. This model utilizes methodology <br /> extracted from the work of the Southern California Regional Rail Authority (SCRRA) and <br /> the California Public Utility Commission (CPUC) to determine vehicle delay at grade <br /> crossings in Southern California. The calculation takes into account a number of factors, <br /> including: <br /> • Existing and future traffic volumes <br /> • Existing and future train trips and number of trains <br /> • Roadway classification/number of lanes <br /> • Type of traffic control at the crossing, and distance of railroad tracks from <br /> intersection (mid-block or adjacent to intersection) <br /> Two key formulas are used to establish peak-hour vehicle delay. For purposes of this <br /> study, the two formulas were utilized to evaluate total gate blockage time and peak hour <br /> vehicle delay. These equations form the basis of the at-grade delay analysis described <br /> later in this report. <br /> Total Gate Blockage Time <br /> TB = 0.603 + ((50 + L +W)/V) <br /> Where: <br /> TB = total blockage time per train in minutes <br /> L = length of train in feet (assumed to be 4,500 feet) <br /> W = roadway width at crossing in feet <br /> V = train speed in feet per second (assumed to be 45 mph or 66 fps) <br /> Note: Train speed limit at Santa Ana Boulevard crossing is 50 mph <br /> The total gate blockage time formula utilizes several physical characteristics about the <br /> crossing, as well as train volumes, to determine blockage time. <br /> Daily and Peak Hour Vehicle Delay <br /> The delay at an at-grade crossing is a function of the time crossing blockage, traffic <br /> volume, and the rate of vehicle queue discharge after the train has passed. This can be <br /> calculated on a daily or peak hour basis. In order to isolate the delay to vehicles incurred <br /> due to rail crossing blockage, the following formula was used: <br /> Delay = (TB * 2)*(q/2)*(1-q/d)) <br /> Where: <br /> Delay = total minutes of vehicle delay <br /> TB = the length of time the crossing is blocked by the train <br /> q = vehicle arrival rate, vehicles per minute <br /> Traffic/Circulation Study—Final May 18,2012 <br /> Page 14 <br />