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Revised Traffic Impact Study March 27,2008 Proposed CEMEX Mining Site Page 7 Table 3 Level of Service Characteristics for Signalized Intersections Level of Description Average Vehicle Delay Service I I (seconds) A Uncon ested o erations; all onlelles clear in a single cycle. <10 B V li ht con estion;an occasional nhase is fully utilized. >10-20 C Li t con emion;occasional numes on a roaches. >20-35 Significant congestion on critical approaches, but D intersection is functional. Cars required to wait through >35-55 more than one cycle during short peaks. No long-standing — queues formed. Severe congestion with some long-standing queues on E critical approaches. Traffic queue may block nearby >55-80 intersection(s)upstream of critical approach(es). -" F Total breakdown,stop-and-Eo conditions. >80 Reference:Highway Capacity Manual, Transportation Research Board Table 4 Level of Service Characteristics for Roadways Level of ServiceT Description A Primarily free flow operations B Reasonably unimpeded operations, ability to maneuver only slightly restricted C Stable operations,ability to maneuver and select operating speed affected D Unstable flow,s eeds and ability to maneuver restricted E Significant delays, owuite unstable F Extremely slow speeds Reference: 1998 Highway Capacity Manual, Transportation Research Board 61—Significance Criteria The San Joaquin County Guidelines for the Preparation of Traffic Impact Studies indicates all _ County roadways shall operate at LOS C or better (except in a City sphere of influence where the City has adopted LOS D); intersections shall operate at an overall LOS D or better on minor arterials and roadways of higher classification; and LOS C on all other roads; all freeways and State highways shall operate at LOS D. In urban areas,a level of service D is often considered acceptable. The Caltrans Guide for the Preparation of Traffic Impact Studies indicates that Caltrans endeavors to maintain a target level of service at the transition between LOS C and LOS D. At unsignalized intersections, a traffic impact would be considered "adverse but not significant" if the LOS standard is exceeded but the projected traffic does not satisfy traffic signal warrants. Under these conditions, the only means to completely alleviate delays to stop-controlled vehicles may be to _ install a traffic signal. However, the unsatisfied signal warrants would imply that the reduction in delay for the stop-controlled vehicles may not justify the new delays that would be incurred by the major street traffic (which at two-way stop-controlled intersections is not currently required to stop). Under these circumstances, installation of a signal would not be recommended and the substandard LOS for stop-controlled vehicles would be considered an "adverse but not significant" impact. With respect to pavement impacts, a significant impact to the existing pavement structural section may be recognized if the Project will increase the traffic index by an amount of 1.0 or more. The traffic index is discussed in more detail in a later section of this report.