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worst. Generally, Level of Service "D" represents the threshold for acceptable overall intersection operating conditions during a peak hour. The acceptable threshold for a particular movement at an intersection depends on both the priority assigned to that movement and its traffic volume. In general,the higher the priority and the higher the traffic volume,the more stringent the acceptable threshold will be. For example,the acceptable threshold for a high-priority/high-volume suburban movement might be"C,"while LOS"F"on a low-priority/low- volume urban movement might be appropriate. For side-street stop-controlled intersections, a key measure of operational effectiveness is the side-street LOS. Long delays and poor LOS can sometimes result on the side street, even if the overall intersection is functioning well, making it a valuable design criterion. Again, depending on priority and traffic volume,acceptable side-street LOS can range from"D"to"F." A final fundamental component of operational analyses is a study of vehicular queuing, or the lineup of vehicles waiting to pass through an intersection. An intersection can operate with an acceptable level of service, but if queues from the intersection extend back to block entrances to turn lanes or accesses to adjacent land uses, unsafe operating conditions could result. The 95ffi percentile queue, or the length of queue with a 5% chance of occurring during the peak hour, is considered the standard for design purposes. To assess the background traffic conditions,RLK used the Existing PM Peak Hour Traffic Volumes that were recorded in the Traffic Impact Study developed as part of the Guiding Plan for the B2 District.2 Access Considerations Along County Road E, access to the development parcels has been limited to two driveways. The westerly site driveway is approximately 975 feet west of Lexington Avenue. The proposed driveway accessing the east side of the apartment building and the conceptual parcel is approximately 425 feet west of Lexington. A central driveway approximately 775 feet west of Lexington previously used for pick- up/drop-off access to the front of the building will be closed. Internal Circulation The internal roadways will allow two-way traffic flow. The westerly drive extends to a parking area at the rear of the proposed apartment building, and then turns easterly to access the parking area for the conceptual parcel. The parking area for the conceptual parcel also can be accessed via the easterly driveway onto County Road E. It is assumed that the cross-access drive in front of the building will operate in a two-way flow,much as it did while a hotel use. To model the distribution of the traffic generated by the market-rate apartments and various uses considered for the conceptual parcel, RLK looked at the trip distribution of the highest generating use being considered. Also, RLK had to determine the directional split of the traffic. For the apartment building, it was assumed that 50% would use the easterly driveway, 50% would use the westerly driveway. For the conceptual parcel,RLK assumed 80%would use the easterly driveway and 20%of the traffic would use the westerly driveway. 2 Traffic Impact Study, Guiding Plan for the B2 District, Arden Hills, NM prepared by Spack Consulting, December 5,2008. RLK Incorporated Page 5 of 6 February 7,2012 Co.Rd.E&Lexington Traffic Study 2011-052-M