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Although no compaction tests were made of the minor fill, I firmly believe that the compaction is <br />adequate for its intended use for the following reasons: <br />1. The fills are less than 2 feet high and in most cases, they are less than 1 foot high. <br />2. The heavy equipment in use at this mine site is capable of producing tremendous <br />compaction in small lifts or even 1 foot lifts. <br />3. Most of the overburden material used in the fill has a good mix of sand, silt and clay <br />which normally achieves an excellent compaction. This is supported by the excellent <br />strength testing done on the overburden material for the sediment pond stability analyses. <br />See Attachment 2.05.3(3)-15 for details of the strength properties of the overburden. <br />4. The mine haul trucks which have used the road produce an extremely large point load on <br />the ground surface, further improving the compaction. <br />5. The road has been in use for 13 years with no problems of any kind regarding stability, <br />compaction and crowning. <br />6. The profile of the road on Map 2.05.3(3)-8 shows that the majority of the grade is less <br />than 4.0% while only one portion of approximately 280 feet is at a grade of <br />approximately 6.97%. This meets the criteria of Rule 4.03.1(3). <br />7. All drainage crossings have been designed with culverts to handle the peak runoff from <br />the 10 year 24 hour event. See Map 2.05.3(3)-1 Surface Hydrology and Attachment <br />2.05.3(3)-1-3 Collection/Diversion Culverts and Ditches for the details of the drainage <br />basins, and the designs of the culverts and roadside ditches. Many of these structures <br />have been in place for many years without any operational problems. <br />8. Side slopes of the minor fills area maximum of 3H:1 V slope and areas mild as 5H:1 V in <br />some places. <br />9. The minimal slopes of the minor fills have been vegetated and are extremely stable and <br />do not result in any measurable erosion or damage to the hydrologic balance. As <br />previously stated, the majority of these fills are less than 1 foot in height. <br />10. The crossing of the reclaimed County Road 2700 and the Northeast Perimeter Haul Road <br />has been specially designed in order to ensure that the County Road does not incur <br />damage as a result of the heavy truck traffic crossing. This crossing was approved by <br />Montrose County in the issuance of the Special Use Permit in 1999. This permit is <br />Section 2.05.3(3) Page 24 April 2017 (MR -104) <br />