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<br />maintenance accessibility, and ease of construction (existing alignment could serve as <br />dewatering channel during construction. He also mentioned that current Bull Seep <br />channel does not have the Reclamation Plan capacity (350 cfs). In addition, he <br />mentioned that the Reclamation Plan design calculations describe a channel consisting of <br />a 25-foot bottom width, 2:1 sideslopes, and a 0.04% channel slope. As designed, this <br />channel geometry would be unacceptable to the District. He mentioned that the channel <br />proposed by ICON consists of a 15-ft bottom width with 3:1 sideslopes. The channel <br />slope for this section was proposed to be 0.2% based on current mapping. A steeper <br />slope would help increase the channel's capacity with a nazrower bottom width, however <br />it must not exceed permissible stable channel velocity typically less than 5 feet per <br />second. <br />7. John Hickman (Mobile/Lafarge) was concerned that ICON and the District were pursuing <br />a channel section that was different from what was preferred by Lafarge. John mentioned <br />that he felt Lafarge would prefer to install a wider channel with less depth. It was agreed <br />that the channel could be widened, however there would be more potential to disturb <br />trees. <br />8. John Hamilton (Muller Eng. representing South Adams County Water & San.) mentioned <br />that there was a potential for the channel to get even deeper (deeper than 4-f[) in areas, <br />depending on the channel profile. ICON confirmed that they had only conducted normal <br />depth calculations and the channel had the potential to become deeper in areas, depending <br />on the profile <br />9. Jessica Barbier (Denver Water) asked whom the current Bull Seep easement is with. John <br />Hickman stated that he thought it was technically an easement granted to the Fulton Ditch <br />Company from Mobile Premix (LaFarge). <br />]0. LaFarge mentioned that there was concern for an administrative delay for changing the <br />Bull Seep easement, however, it was agreed that this delay would likely take place no <br />matter what the preferred alignment was since the 47 feet easement granted appears to be <br />too small given the need to provide maintenance access. John Hickman also mentioned <br />that Tom Schreiner (Colorado Division of Mining & Geology) thought that Lafarge <br />might need to go through a 3 to 4 month process to amend the mining permit on the <br />Howe-Haller property. <br />11. Jim Weldon (Denver Water) was concerned about the velocities in the Bull Seep Slough <br />immediately downstream of the proposed drop structure. Craig mentioned that typical <br />velocities in Bull Seep were around 3ft/sec and he did not expect them to be much <br />different in the Slough. Bryan mentioned that similar to the South Platte River Grade <br />Control Structure, the banks adjacent to the Bull Seep Slough Drop would be riprap lined <br />in order to resist localized velocity increase. <br />12. John Hickman mentioned that the Bull Seep Slough Drop appeazed to be moved to the <br />south, as compared with the drawings presented in the last meeting. Craig mentioned that <br />i[ was moved south to try to minimize the drop width, to save on cost. Bryan stated that <br />the drop would likely be design as faz north as possible. The drop size may need to be <br />increased as a result. <br />13. John Hamilton asked how the new mapping was developed. Matt explained that the <br />mapping flown by Denver Water in January 2001 was supplemented with field survey by <br />ICON and Denver Water, and then combined and re-surfaced to develop a new project <br />map. The mapping also included a completely new topographic survey around the <br />G \W INpOW S\TEMP\9-1] Meeting Edils doc <br />