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<br />-'j <br />-I <br />-I <br />-I <br />-I <br />-I <br />-1 <br />-I <br />-1 <br />I( <br />~ <br />~ <br />II <br />II <br />) <br /> <br />- <br />J <br /> <br />II <br />II <br />II <br />t <br /> <br />II <br />I <br /> <br />II <br />I <br /> <br />3. State of Colorado Construction Materials Regular (11Z) Operation Reclamation <br />Permit Applications Form filled out by Four States Aggregates, LLC, File No. M- <br />ZOOI-OOl. <br />4. State of Colorado Division of Minera1s and Geology response to objections <br />received to the Four States Aggregates, LLC, Line CaIJ?p Pit, File No. M-ZOOI- <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. Website USGS Hydrograph and station description for 09166500 <br />(http://water.usgs.gov/peak.cgi?statnum=09166500...), 2001. <br /> <br />Findings' <br /> <br />1. Four States Aggregates's final reclamation design (Exhibit Page 23, File No. M- <br />ZOO-OOI) indicates a berm 350 ft long will occupy the southeastern edge parallel <br />to the river and a 700, ft berm petpendicular to the valley slope at the extreme <br />southern edge of the gravel pit area. <br /> <br />Z. As can be seen frOIp. 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 are indicative of steeper <br />gradients, unstable bedloads (gravel and sand that JIlakes up the stream bed) that <br />, result in shifting channels especially during flooding. Braided channels are <br />associated with greater bedloadthanwhat the river discharge can handle and, <br />thus,the channel splits into multiple threads. <br /> <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 (seephoto 198-57), The Akin property is thus susceptible to <br />the effects of braiding and erosion of high banks during high discharge events. <br /> <br />4. High 'discharge events are considered here as volumes greater than 6,000 cubic <br />feet per second (cfs). There have heen eight such events in the last 90 years (see <br />Peak Streamflow for Colorado, Dolores River). V oIurnes between 6,OOQ 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 /> <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 chaimel 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'ofthe channel. To <br />prevent this, berms are often constructed. . <br /> <br />Affidavit of Dr. Robert W. Blair, Ph.D. <br /> <br />Page - 2 <br />