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Coulson Excavating Company, Inc. -Stroh Gravel Pit Exhibit D -Mining Plan Table 1. Overburden and Gravel in South Zoue of Stroh Pit. South Zone Cells Area (ac) Volume of OB [yard ] Tons of Gravel [tons] 1 18.7 260,528 797,216 2 23.2 322,280 986,175 3 27.6 383,661 1,174,004 Total 69.5 966,469 2,957,395 Average 23.2 322,156 985,798 Mining Operations and Timetable The mining operation will be divided into two phases. Phase I will mine and reclaim to the east of the gas line and will include Cell-1. Phase II will mine and reclaim to the west of the gas line and will include Cell-2, Cell-3. Phase I will complete all reclamation before Phase II begins. Approximately 300,000 tons of gravel will be extracted from the pit each year. Gravel extraction will follow standard gravel mine operations and is expected to follow an annual schedule similar to that shown in Table 3. The monthly gravel tonnages shown are approximate. Mining Constraints The sequence in which mining will occur is constrained by the following: (i) The presence of occupied Preble's meadow jumping mouse (PMJM) habitat along the riparian corridor. (ii) The encroachment of the floodway along portions of the northern section of the pit. (See Exhibit D -Mining Plan) Suitable mouse habitat is present along the Big Thompson River on the north boundary of the proposed pit. Therefore, the U.S. Fish and Wildlife Service (USFWS) considers this stretch of the Big Thompson River to be occupied by PMJM. PMJM have been shown to forage in areas away from riparian corridors. The USFWS suggested that a permanent buffer at least 100-ft wide be established between the pit and the existing riparian corridor on its north side. As such, the pit boundary was offset 100 ft south of the permit boundary and the area to be mined excludes this strip of land and is referred to as the permanent PMJM buffer (hatched green in Exhibit D).