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Coulson Excavating Company, Inc. -Stroh Gravel Pit Exhibit D -Mining Plan An adjacent 200-ft wide strip from the pit boundary (called a seasonal PMJM buffer- green line in Exhibit D) has been established and will be during winter months when PMJM are in hibernation. A hydraulic modeling study was performed by WSI in the area of the Stroh pit. The results of the study show the floodway encroaches into parts of the pit in the northern section. Table 3. Operation Summary and Schedule. Month Monthly Percentage Monthly Tonnage January 4.1% 12,300 Febnrazy 5.5% 16,500 March 4.1% 12,300 April 5.3% 15,900 May 5.9% 17,700 June 9.9% 29,700 July 10.0% 30,000 August 10.8% 33,000 September 12.0% 36,000 October 17.6% 52,800 November 7.1% 21,300 December 7.5% 22,500 Total = 300,000 Water Diversions and Impoundments A dewatering trench will be dug at the toe of each working cell wall. Dewatering effluent (groundwater) will be pumped to asediment-settling pond and allowed to gravity feed to the river. During the first half of mining activities, water from the dewatering trenches will be pumped to a 0.5-acre sediment pond located in the northwest corner (Cell 1) of the eastern half of the project area. Throughout the second half of mining activities, water will be pumped to another 0.5-acre sediment pond located in the northwest corner (Cell 8) of the western half of the project area. No other water diversions will exist within the project azea. Although a system to irrigate hay does exist at the site, it will not be in use during the operation. The current irrigation consists of shallow trenches that connect to a main canal leading to the Hillsboro Ditch (See Exhibit C). After mining is complete, the trenches will be reinstated to their original state, with the exception of areas reclaimed as ponds.