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5. Ken McIntosh (McIntosh Farms) requested [hat the crest elevation be shown to him in the field so that he could make ajudgment as to the acceptability of Lafarge's plan. 6. A discussion followed concerning the elevation of the channel in the Bull Seep Slough. Bryan Kohlenberg asked why Lafarge proposed to keep the channel lower through this reach. Chris Lidstone and John Hickman mentioned that the lower elevation was required to get the required capacity (4800 cfs) for the First Creek major Flows, while minimizing the impact to the trees in [he area. Ken added that it was his opinion that a shallower, higher channel would more effectively supply the trees with groundwater. Chris explained that it was his belief that the groundwater would be coming from the South Platte River, to the west of the site, and that the Bull Seep Slough would be acting as a discharge channel as opposed to a recharge channel. Meaning that, if the Bull Seep Slough was set lower, water would still effectively travel through the conservation easement, between the South Platte River and the Bull Seep Slough. He also added that if the main objective behind the design was to restore the channel grade to the pre-May 5'h level, evidence indicates it was below elevation 5023. 7. Jim Weldon (Denver Water) asked about the possibility of raising the channel invert above elevation 5023, but not controlling the entire 4,800-cfs release rate to the South Platte. Mike Applegate (Applegate Group) said that raising the proposed slough drop crest above elevation 5023 would prevent the ability to pass 4800-cfs with a channel section about 300 feet wide. During the 4,800-cfs release rate, Reservoir B's outlet is performing more like an open channel than a control weir. 8. Bryan Kohlenberg added that the mining operation has a responsibility to safely manage offsite flows from their site. Historically, there has not been a well defined floodplain for [he 4,800-cfs Firs[ Creek 100-year Flows. The flow has now been concentrated due to the mining operation. In the future property owners may be able to claim damages caused by flow that did not historically flow through the slough unless these flows are adequately handled.. Bryan also added that he was unsure if the UD&FCD could assist with maintenance on a channel that was not a 100-year design. Jim Weldon added that there might be a potential for Denver Water to obtain a flood easement from Ken for any overflow on his property as a result of the First Creek 100-year discharge. 9. Barry Marrs (Brantner Ditch) asked how the proposed crest elevation of the Bull Seep Slough drop compared with the typical channel invert downstream on the South Platte River. He had a concern that the concentration of the 100-year flow from First Creek could lead to additional scour on the South Platte River, and as a result increase erosion potential at the Brantner Diversion Structure. Bryan Kohlenberg informed him that the UD&FCD had plans to install a grade control immediately downstream of the Bull Seep Slough confluence, The grade control will reduce additional scour potential at the Brantner Diversion Structure. 10. Ken McIntosh again mentioned that he would like the proposed elevations identified in the field to help him make a decision. As a result, a field meeting was set up for Friday, November 30'h at 12:00 pm. All attendees should meet at the Lafarge Scale House. 11. Lafarge's plans also identified a 1-foot drop at the confluence with the Bull Seep channel and Bull Seep Slough. Ken McIntosh asked if this drop could be C:\\CI\1)011'5\~ff~.\9P\I I-'S mrttinc.di~~ .W{~FF4L3'=~h ~ ._~ ~n ...,. ~ i..