2006-06-12_REVISION - M1978314 (2)

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April 25, 2005 Mr. Carl Luppens Page 5 Other roadway improvements are requested in the McLaughlin memorandum. The McLaughlin memorandum details the current, substandard condition of the two bridges on CR 5 that cross Egeria Creek. In addition to structural problems, they are functionally obsolete as they both are only wide enough for one-way traffic. Field measurements show that there is 20 feet between the rails on the lower bridge and 23 feet for the upper bridge. This leaves 12 and 15 feet (respectively) for traffic, considering normal lateral clearance distance from the rails. This is not enough width for cars to pass, let alone trucks. Regardless of the surtace treatment for CR 5, both of these bridges should be replaced with new bridges that have 30 feet wide decks. County standards also state that the "Clear deck width is to accommodate the full width of the traveled lanes and shoulders of approach roads.' (g) There are 90 degree turns near each end of the upper Egeria Creek bridge. The north curve has a larger radius than the south turn and a nearby irrigation ditch would complicate widening the curve. The south curve is smaller and widening the curve would appear to be straightforward if additional right-of-way can be obtained. County standards call for a Centerline radius of 100 to 300 feet, depending on the classification of the roadway. The intersection of CR 5 and CR 3 is a safety concern. Sight distance on all three approaches to the intersection is limited. The north leg of the intersection {CR 3) has a very steep grade (over 18°~) as it approaches the intersection. Trucks crawl down this grade at very low speeds, but there is doubt that they can stop for oncoming traffic if necessary. With the higher level of truck activity that is forecasted, the alignment of this road should be changed to reduce the grade of this road. Routt County standards call for a maximum grade of 7% with no more than 4% within 100 feet of an intersection. Regardless of the improvements to the intersection, the slopes adjacent to the CR 3 approach to the intersection road should be modified to improve sight distance and safety. Finally, all materials show that trucks will be using CR 5 exclusively in the future. CR 3 continues north of the mine and also connects to SH 131 closer to Yampa. For traffic to and from the north, CR 3 is shorter by approximately 8 miles than using CR 5. There is a steep draw and two long downgrades on CR 3 that would present safety problems for heavily loaded trucks. Trucks should therefore be prohibited from using CR 3. This will also concentrate maintenance activities on CR 5. Current CR 5 Volumes During portions of three hours when we conducted our field visit, we observed five separate gravel trucks (10 trips) on CR 5. Three of these trucks were observed to be turning either to or from the south on SH 131. (The origin/destination of the other two was not observed). The various materials we have reviewed impty that the mine has historicalty produced an average of 10,000 to 20,000 tons per year. Last year the tonnage was approximately 100,000 tons with 80% of that for one job. The LSC report calculates 43 daily truck trips for an average month at the proposed 100,000 ton per year level. April would seem to be a relatively low volume month, and 10 truck trips in three hours would appear to be a relatively high volume for an activity level of approximately 20,000 tons per year. This higher than expected level of activity can be attributed to one of the following: