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3. State of Colorado Constmction Materials Regulaz (112) Operation Reclamation <br />Permit Applications Form filled out by Four States Aggregates, LLC, File No. M- <br />2001-001. <br />4. State of Colorado Division of Minerals and Geology response to objections <br />received to the Four States Aggregates, LLC, Line Camp Pit, File No. M-2001- <br />001. <br />5. USDA-F color stereo aerial photos 24-612130-198-56 and 198-57, 1998. <br />6. SCS b&w stereo aerial photos DKQ-4-147 and 4-148, 1950. <br />7. Websiie USGS Hydrograph and station description for 09166500 <br />(http://water.usgs.gov/peak.cgi?statnum=09166500...), 2001. <br />Findings <br />1. Four States Aggregates's final reclamation design (Exhibit Page 23, File No. M- <br />200-001)indicates aberm 350 ft long will occupy the southeastern edge parallel <br />to the river and a 700 ft berm perpendicular to the valley slope at the extreme <br />southern edge of the gravel pit area. <br />2. As can be seen from aerial photo 198-57, the Dolores river is presently a single <br />thread channel confined to the eastern valley wall north of the Akin property and <br />then shifts to a single thread channel on the western valley wall south of the Akin <br />property. The shift of the river from one side of the valley to the other is indicated <br />by a braided channel network. Braided channel patterns aze indicative of steeper <br />gradients, unstable bedloads (gravel and sand that pukes up the stream bed) that <br />result in shifting channels especially during flooding. Braided channels aze <br />associated with greater bedload than what the river discharge can-handle and, <br />thus, the channel splits into multiple threads. <br />3. The Akin property is situated at the northeastern edge of the braided section. The <br />proposed Line Camp gravel pit is located on the west side of the valley just north <br />of the braided section (see photo 198-57). The Akin property is thus susceptible to <br />the effects of braiding and erosion of high banks during high discharge events. <br />4. High dischazge events aze considered here as volumes greater than 6,000 cubic <br />feet per second (cfs). There have been eight such events in the last 90 years (see , <br />Peak Streamflow for Colorado, Dolores River). Volumes between 6,000 cfs and <br />8,000 cfs would most likely involve the reoccupation of existing braided channels <br />and if the flood had a duration of several days could form new channels. <br />5. Very high discharge events or catastrophic flood events would be volumes greater <br />than 8,000 cfs. There have been three of these events in the past 90 years. During <br />such events the channel configuration could be completely redesigned. It is likely <br />that with the presences of gravel pits that pit capture would take place. This is <br />where the floodwaters will take the path of least resistance. Thus, human <br />alteration of the natural floodplain would aid in the relocation of the channel. To <br />prevent this, berms are often constructed. <br />Affidavit of Dr. Robert W. Blair, Ph:D; ' -' Page - 2 <br />