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Dewey George -2- GX-95-1 The release rates provided for new Hogan Reservoir do not constitute a stream profile analysis as requested in the June 10, 1996 letter. On page 2 of the letter to you dated March 7, 199E from Earl Cummings, under the heading of Rip Rap, he notes that the size of the rock depends on the tractive force from the water and to determine the tractive force you need to know the velocity of the river. Mr. Cummings goes on to say that the County may ask you to have an engineer to _-certify the size_o� the rock. Mr. Cummings enclosed a nomograph and tables for your information. The nomograph and tables are the same information that was supplied to us by Rjeldsen & Sinnock when they did their independent review. The tone of Mr. Cummings letter is that he is providing you general information in order to help give you direction on how to proceed. His letter does not constitute an engineering report. The letter does not have a letterhead nor does Mr. Cummings state his professional capacity in writing the letter to you. Again, we need the depth of flow and the velocity component in order to determine both the revetment size and height from the channel bottom. You also have not provided the information requested relative to certain events that control the release rates i. e. , summer flows, normal winter flows and flood control releases. + A benchmark with a known datum was requested. The only information provided was someone wrote 11162" in the margin on the return copy of my June 10, 1996 letter to you. There is no explanation as to what 11162" renresents. • The last main point in my June 10th letter is that there has been no justification submitted to support- the upportthe extensive excavations that you are proposing. With your most recant submittal, still nothing has been provided to support or justify the extensive grading. On the first page of the letter to you from Earl Cummings, he suggests that you create a 20 foot wide working bench at the present water level and from there go up on a slope of 3-1 to the present orchard level. Mr. Cummings suggests that you consider a first stage project for the "big bend" area, as he calls it, and then consider whether you want to do additional bank stabilization downstream. As Mr. Cummings indicates to you, the lower bank is not subject to erosion and collapse because vegetation has begun to grow and � . stabi_ize _he bottom of that Dark.