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natural and progressive bank erosion processes (i.e., the geomorphology of the river), were the principal mechanism of failure. The DMG has been supplied information by UDFCD, including digital and aerial photographs from January and Feburary 2001 respectively, that show that a significant breach at the location of the May 5 event predated such event by at least five (5) months. See Applegate Figure 1-7. This breach captured and diverted a 2 to 5 year flood event that occurred on May 5, 2001, and also likely captured other events during the intervening months, thus decreasing the relative elevation of flows that would be capable of flowing through the pre-existing bank cut. Exhibit B hereto, entitled "Forensic Analysis of Bank Failure and Stream Capture Adjacent to Mobile Premix Concrete, Inc. Howe Pit," prepared by Lidstone and Associates, Inc. ("Lidstone Report"), reached the conclusions summarized below based on information readily available to DMG, UDFCD and interested third parties in this matter. (1) The Brantner diversion structure was constructed in 1947 and since its construction has served as a grade control downstream of the May 5, 2001 bank failure area and prevented significant vertical adjustment of the South Platte River in the immediate upstream reach. (2) The 1973 100-year flood breached the east South Platte River channel bank and opened a channel that is now known as the Bull Seep Slough, which Slough was subjected to annual backwater from the South Platte River. (3) Sometime after the passage of the 1973 flood event the Brantner Ditch Company repaired the breached riverbank. The repair was not completed using standard, acceptable engineering design or construction practices. The breach was reportedly repaired by placement of silts and off site derived materials. The river side of the repair work was protected by broken slabs of concrete, a method of bank protection that does not meet standard, acceptable engineering practice. (4) In-channel mining in the South Platte River in the 1970s and 1980s took place at a location upstream of the May 5 breach area. The effect of this mining was to "rob" the normal river flows of their natural bed material sediment load and to create a "hungry" water condition. Increased bank erosion and increased tendency to meander (i.e., sinuosity) resulted from the "hungry" water condition. (5) Over the subsequent 20 years, the angle of channel flow became progressively more acute to the 1973 repair area. Hydraulic conditions became progressively more severe such that the mode of attack and ultimate failure of the 1973 repair area on May 5, 2001 was slow, progressive and originated from the river, not the Bull Seep alignment. The May 5, 2001 flood event represented the culmination of these 8