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2. Appendix F: 2012 Traffic Analysis Appendix F: 2012 Traffic Analysis THIS PAGE INTENTIONALLY LEFT BLANK. Zavoral Mine 8� Reclamation Project EIS 2012 Traffic Analysis TH 95 and TH9 7 Intersection Analysis AECOM completed a level of service (LOS)analysis for the intersection at TH 95 and TH 97. Traffic counts were collected during the morning and evening rush hour on Tuesday June 12,2012. These times were chosen to reflect typical AM and PM peak hour traffic conditions. Tiller was not conducting a haul event from Franconia, Minnesota and/or Osceola, Wisconsin during the June traffic counts. A LOS analysis was completed for three scenarios at the TH 97 and TH 95 intersection: 1) Existing AM and PM peak hour traffic 2) The No-build alternate with a haul event from Franconia, Minnesota and/or Osceola, Wisconsin occurring at maximum hourly haul rates. 3) The Proposed Site in operation at hourly haul rates that ranged from 56 to 62 trips per hour which is equivalent to 560 trips per day(10 hour day)to 744 trips per day(12 hour day). These truck trip rates cover the range of proposed operations under Alternatives 1, 3, and 3A. Existinq AM and PM peak hour traffic The LOS analysis for existing conditions showed that the LOS is Level A or B during the two peak traffic times under most turning conditions. The LOS drops to Level C for two afternoon turning movements, eastbound (left turn)and Eastbound Approach, as shown below. Existing Conditions—Unsignalized Intersection Level of Service Intersection Dela & Level of Service LOS/Dela in seconds er vehicle Northbound Eastbound Eastbound Eastbound left turn left turn ri ht turn A roach TH97&TH95AM A/8.4 B/ 12.0 A/9.6 B/11.6 Peak TH97 &TH95PM A/8.0 C/ 16.5 A/9.0 C/15.9 Peak No-build altemative with a haul event from Franconia, Minnesota and/or Osceola.Wisconsin occurrinp at maximum hourlv haul rates The LOS analysis for the No-build Alternative showed that the LOS is Level A or B during the two peak traffic times under most turning conditions. The LOS drops to Level C for two afternoon turning movements, eastbound (left turn)and Eastbound Approach, as shown below. Alternative 2 No Build Haul Conditions— Unsignalized Intersection Level of Service Intersection Dela & Level of Service LOS/Dela in seconds er vehicle Northbound Eastbound Eastbound Eastbound left turn left turn ri ht turn A roach TH97&TH95AM A/8.6 B/ 13.5 A/9.6 B/ 13.1 Peak TH97&TH95PM A/8.1 C/21.8 A/9.0 C/20.8 Peak Proposed Proiect alternatives in operation at maximum hourlv haul rates The LOS analysis for proposed conditions showed that the LOS is Level A, B or C during peak traffic periods under most turning conditions. The LOS drops to Level D for two afternoon tuming movements as shown below. Altematives 1 and 3-Unsignalized Intersection Level of Service Intersection Dela &Level of Service LOS/Dela in seconds er vehicle Northbound Westbound Eastbound Eastbound Eastbound left turn thru left turn ri ht turn A roach TH97&TH95 A/8.5 C/ 16.9 C/ 15.5 A/9.6 B/14.7 AM Peak TH97 &TH95 A/8.0 C/ 18.6 D/32.0 A/9.0 D/30.2 PM Peak The results of the LOS analysis for the intersection of TH 97 and TH 95 did not change in comparison to Alternatives 1 and 3 as shown below. Subalternative 3A- Unsignalized Intersection level of service Intersection Delay and Level of Service(LOS/Delay in seconds per vehicle) Northbound Westbound Eastbound Eastbound Eastbound left turn thru left turn ri ht turn A roach TH97andTH95 A/8.5 C/ 17.0 C/ 15.8 A/9.6 C/ 15.1 AM Peak TH97andTH95 A/8.0 C/ 18.8 D/34.1 A/9.0 D/32.2 PM Peak Scandia Elementarv Driveway An intersection turning movement analysis was completed for buses and cars at the Scandia Elementary school driveway. The traffic counts were based on peak hour Automated Traffic Recorder(ATR)data provided by MnDOT, bus data, and maximum truck traffic rates. The specific ATR data used represented the time when school peak traffic hours occurred in the morning and afternoon. The LOS analysis showed the moming peak had a level of A and the afternoon peak had a Level of B. This indicates that sufficient gaps are present in traffic to allow buses and cars to access TH 97. Also, the LOS for the intersection at Scandia Elementary School for Subalternative 3A did not change when compared to the other build alternatives. Intersection Analvsis Summarv The LOS analysis showed that the TH 95 and TH 97 intersection has sufficient gaps under all scenarios and all traffic patterns. During the morning rush hour the LOS for all scenarios is Level C or better for all turning movements for all scenarios. During the evening rush hour the LOS is at Level C or better for all turning movements for all three scenarios except evening rush hour for the eastbound approach and eastbound left turn. According to Section 5.3, Figure 5.2 of the Mn/DOT Traffic Impact Study Guidance these levels are considered to be acceptable for this type of intersection. The LOS analysis for the Scandia Elementary driveway has sufficient gaps under all alternative traffic scenarios and traffic patterns. Intersection Potential Mitiqation Measures A requirement to reduce truck traffic levels during the time period from approximately 4:00 PM to 6:00 PM on weekdays is a potential mitigation measure that the Ciry may require through the CUP process to reduce traffic congestion at the TH 97 and TH 95 intersection. The city's ordinance already prohibits mining operations from occurring on weekends or holidays. Additionally, truck tra�c could be restricted on Friday afternoons when tourist traffic is most likely to be present in the area. Copies of the Intersection Capacity Analyses are included in Attachment A. TH 97 Corridor Analysis The alternatives for the TH 97 corridor vary in the range of"daily haul volumes"based on the planned duration of mining or the No Build (not a defined number of years for mining). The truck volume analyzed was the Maximum Daily Capacity(and Maximum Hourly Capacity). The morning and evening peak hour traffic volumes were analyzed (based on ATR data from MnDOT)for the roadway segment on TH 97 from Lofton to TH 95 using Highway Capacity Analysis software. For both the morning and evening conditions, the segment is LOS C. Use of peak hourly traffic data plus maximum truck tra�c obviates the need to run multiple analyses for lower traffic volumes. The corridor summary for the AM and PM peak hours is shown in Attachment B. Sight Distance Analysis AECOM completed an analysis for the following sight distances. 1. Sight Corners MnDOT has a requirement that no obstructions be placed in the sight corners of the intersection. The sight corners for the proposed new driveway have found no obstructions. The Sight Corner Exhibit is contained in Attachment C. 2. Enabling a Stopped Vehicle to Cross a Major Highway At an intersection with stopped control, the operator of the stopped vehicle must have sufficient visibility to cross the mainline road without interfering with oncoming vehicles. The MnDOT sight distance required for this is defined as D=1.47V(J +T), where D =minimum sight distance, V= design speed of the mainline highway, J=perception/reaction time (use 2.0 sec.), and T=time required to traverse the highway(110ft @ 10mph)=7.5 sec. Therefore, D = 1.47(55)(2+7.5)= 768 Ft. Based on a review of topographic maps with a contour intervai of 1 foot of TH95,the existing sight distance is approximately 1,400 feet in both the north and south directions. This exceeds the MnDOT requirement of 768 feet for stopping sight distance. 3. Turning Left onto a Major Highway At an intersection with stopped control, the operator of the stopped vehicle must have sufficient visibility to turn left onto the mainline road. Figure 5-2.02F of the MnDOT Road design Manual shows that 780 ft of sight distance is needed for the vehicles coming from the south. As noted above, the northbound sight distance is approximately 1400'. The MnDOT Figure 5-2.02F is included in Attachment C. 4. Signal Control This is not a signalized intersection, so this section does not apply. 5. Effects of Skew This is not a skewed intersection, so this section does not apply. 6. Effect of Grades Adjustments to the intersection only need to occur when grades exceed 3%. The grade of Highway 95 is roughly 2%, so no adjustments are necessary. Based on the above analysis,the existing sight distance at the TH 95 and TH 97 intersection meet the MnDOT standards for the proposed Project modification to a four way intersection. TH 97 and TH 95 Road Conditions As part of the proposed project, Tiller Corporation has stated that truck hall traffic currently using TH 95 from Franconia and Wisconsin would be offset by truck traffic from the Zavoral Site. Thus, truck traffic and its associated impact on TH 95 would decrease. Tiller Corporation has also stated that under the proposed scenarios,the maximum truck traffic on TH 97 would not increase. Therefore, impacts on TH 97 would not change. MnDOT completes an annual evaluation of TH 97 and TH 95 as part of their road inspection program. As shown on the figures in Attachment D, in 2011 TH 97 was rated as having very good pavement quality, good ride quality, very good surface rating and an expected lifespan of 4 to 11 years. Additional Mitigation Measures The City of Scandia ordinances would prohibit operation of the proposed Zavoral Site on weekends or holidays. In order to minimize potential impacts to tourism, the prohibition could be extended to Friday afternoons to avoid conflicts with recreational travelers using TH 97 and TH 95.