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Mr. Gregg Squire Page 4 December 21, 2000 The water intake for the City of Rifle is located on the north side of the Colorado River approximately 1600 feet downstream from the west property boundary of the project site. The vicinity map has been revised to show the location of the City of Rifle's intake since the scale of Exhibit C-1 does not cover that area. Exhibit C-1 has been revised to indicate the location of the City of Rifle's intake from the west property line. Item 8 -Mining schedule renewable resource area. As stated in Item 2 above, the renewable resource area will be mined in low flow periods only. The low flow period is generally expected to be between October 1 and March 31. However, the low flow period will vary depending on snow pack and weather conditions in the drainage basin. As such the renewable resource area operating schedule may vary from that mentioned above if the water level in the Colorado River is low enough to allow safe mining in the renewable resource area before or after the above mentioned dates. After the initial mining of the renewable resource area, the frequency of mining will be determined by the rate of recharge and is expected to be variable ranging from as frequently as annually to as low as once every five years. item 9 -Renewable resource area barriers. The 150 feet barriers are proposed for both the upper and lower ends. The upper end barrier is used to minimize potential erosion of the barrier by the river as the high runoff flows overtop the barrier and enter the renewable resource area. The lower end barrier is designed to control the flow of water leaving the renewable resource area in high flows and to keep out backwater flows from the main channel when the river flows are low. The barrier design for both ends spans the total distance between the banks of the river thereby creating a bank that is 150 feet by 300 feet on the upper end and 150 feet by 225 feet on the lower end. These dimensions are on top of the barrier. The base of the barrier will be larger. The perimeter of the renewable resource area in between the upper and lower end barrier is protected by the 3:1 slope left in place after mining. Item 2 in the response to Mr. Allen Sorenson's review comments provides the specific design details for the barriers. item 10 -Verifying mining depth in the renewable resource area. Item 1 in the response to Mr. Allen Sorenson's review comments provides the cross section information and describes the method to verify depth. item 11 - Bedload deposition renewable resource area. BAI is not aware of any bedload studies for this section of the Colorado River. The renewable resource area has been proposed to see if the river can provide sufficient bedload deposition for the concept to be viable. Roaring Fork Resources wishes to study the feasibility of mining an overflow area of a river because it provides the potential to mine gravel with minimal environmental impacts. The cross sections established to verify mining depth will also be used to determine the bedload deposition after the runoff is over and prior to mining the renewable resource area after the initial mining.