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respectively. This result was expected since the width of the river increase in the vicinity of the <br />breached gravel pond, flow velocities decrease, and aggregates are deposited. <br />United Companies has decided not to continue in -river mining. Since the permit expires on <br />February 15, 2015, maintenance provisions under Special Condition 8 that state "if the channel <br />doesn't meet design dimensions, material will be removed from the channel" will not be <br />continued after the February 15th date. The remainder of this report discusses the bank <br />stability survey and the implications of a migrating channel. The survey begins upstream with <br />the J -hook structure. <br />The J -hook (Figure 4) continues to operate as designed, routing surface flow to the center of <br />the channel creating a pool immediately downstream of the structure. This pool continues to <br />dissipate the energy of the river, protect the downstream bank, while maintaining the grade of <br />the river as designed. Cobble material placed downstream of the J -hook on the sloped river <br />bank is in place and protecting the bank. <br />The toe wood and short vanes on the Chamber's property are shown in Figures 5 through 7. <br />The upstream rock vane is intact and operating as designed. However, the spring flood flows <br />damaged the toe wood bench and the downstream rock vane. The lack of protective <br />vegetative cover contributed to the erosion experienced by the tool wood structure and the <br />downstream rock vane. <br />As shown in Figure 5, several feet of the sod mats were eroded exposing the toe wood. The <br />structure remains intact from the flood waters but is now vulnerable to future flood events. <br />The vegetation shown in the photo are weeds such as Russian Thistle. Unlike the toe wood <br />bench on United's property, no grass or willow transplants survived. Consequently, the critical <br />vegetation that protects the toe wood structure on the Chamber's property was not in place <br />during the 2014 flood. A photo from May 27th, 2014 (Figure 8), a week before peak flood flows, <br />showed only weeds covering the toe wood bench on the Chambers' property. The owner <br />placed animal pens on the bench that prevented the establishment of perennial vegetation. <br />Both toe wood benches were watered for several months by truck after construction was <br />completed in 2012, but as discussed in last year's Annual Monitoring report, the survival rate of <br />the transplanted vegetation was low. However, there were healthy grasses and willows <br />present on both benches as reported in last year's Annual Monitoring Report. <br />Figure 7 shows the remnants of the downstream rock vane. The rock sill designed to prevent <br />high river flows from getting around the structure survived but was exposed. Surface flows <br />accelerated as spring flood waters flowed over on the downstream side of the Chambers <br />peninsula without protective vegetation resulting in excessive erosion. <br />The small riprap section of the side channel that enters the river immediately upstream of the <br />Chambers toe wood bench remains intact (Figure9). Willow cutting placed in between the <br />rocks as required by Special Condition 9 did not survive. Several new willow cutting were <br />2263 Kingston Road I Grand Junction, CO 81507 1 (970) 985-9606 1 peter.kearl(a�hotmail.com <br />