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Mr. Jeffrey W. Schwarz, Esq. 10/14/01 Page 2 (approximately 300 tons), in the eroded portion of the roadway, in an attempt to protect the nearby reservoir liner and to halt any further erosion and damage of the existing roadway. Based on our site investigation, review of photographic evidence, and witness statements, we believe that the opinions expressed in the June 13 meeting naming the current location of the Bull Seep as the cause of the riverbank failure to be incorrect. Our findings follow: On June 17, 1965, a flood event in the range of a 100-year return period (29,600 cfs peak at Henderson, CO) occurred along the South Platte River. Prior to this event, the Bull Seep Slough cannot be easily identified from the aerial photographs. (See Figure 1-2) Water can be seen to collect in low spots adjacent to South Platte River levee in the approximate location of the relocated Bull Seep. In the .1966 photo, it is apparent that a large flood event has taken place. The Bull Seep Slough alignment can now be readily identified in the photo. A significant amount of water can be seen to the east of the South Platte River Levee in the Bull Seep Slough and in low spots that aze near the relocated Bull Seep alignment. It appears that portions of the riverbank were damaged, although the exact extent cannot be easily determined from the photo. On May 6, 1973 another flood event in the range of a 100-year retum period (33,000 cfs peak at Henderson, CO) occurred along the South Platte River. In the1972 photo of the area in question that predates the 1973 event, it is difficult to discern the exact alignment of the Bull Seep Slough channel. (see Figures 1-3 and 1-4) This is due to the lack of visible standing water and the significant overgrowth of vegetation that had occurred since 1965. [n the 1973 aerial photo of the area in question, the Bull Seep Slough channel can be clearly identified and seen to very closely resemble the Bull Seep Slough that is present today. There was a significant amount of water present in the Bull Seep Slough at the time of this photograph that shows a large, well-defined channel. It is therefore our understanding that the levee in question was breached during the 1973 flood event and according to Mr. Ken Macintosh, an adjacent property owner, immediately repaired by the Brantner Ditch Company. During the June 13`h meeting at the UDFCD's offices, Mr. Macintosh described how material comprised of silt and unconsolidated fill had been removed from the Macintosh property by the Brantner Ditch Company and used to re-build the riverbank. There was no indication from Mr. Macintosh's statements on June 13 that the repair made by the Brantner Ditch Company was engineered nor did representatives of the Brantner Ditch Company that were present at the meeting make any such representations. Photographs of the filed riverbank displayed by the UDFCD, in cross section, were presented at the June 13`h meeting. These photographs substantiate the materials that were used in the reconstruction of [he riverbank. It was stated that large flat slabs of concrete rubble were added for erosion protection to the west, or river side of the riverbank. The upper reach of the Bull Seep Slough that was created during the 1965 event and that was