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Susan Bur • maier -4 December 31, 2012 <br />BRL: Please see revised pages App. B -19, 21 and 22. The revision date will remain 11/12 <br />as no changes were made to the ditch design with this adequacy response. <br />13. Page App. B -24 indicates that the discharge at Ditch D -F7a is 26.80 cfs. The <br />SEDCAD run on page App. B -16 indicates that the discharge is 33.44 cfs. It appears <br />that the 26.80 cfs value was a holdover from the calculation for Ditch D -F4 on page <br />App. B -20. Please revise the calculation on page App. B -24 to coincide with the <br />runoff figure calculated on page App. B -16. <br />BRL: Please see revised page B -24. In addition, pages B20, B39 and B40 were revised <br />due to a typographical error that had been carried through all the pages. <br />14. There appears to be a conflict on Pages App. B -2 and App. B -30 as to whether Ditch <br />D -F13 will be trapezoidal or triangular. Page App. B -2 indicates that it will be <br />triangular, but the design on page App. B -30 is for a trapezoidal ditch with 0.0' bottom <br />width. Please clarify the dimensions and configuration of Ditch D -F13 and <br />revise the pages for consistency. <br />BRL: Ditch F13 is a triangular ditch, please see revised page B -30 showing 'Triangular' <br />ditch. <br />15. Page App. B -41 indicates that the overall slope for the West Diversion Ditch #1 will be <br />2.0 %. This appears to be accurate for the overall ditch length, but does not consider <br />the steeper section of the ditch that runs north /south parallel to the D -F21 and D -D3 <br />ditches. The Division estimates, based on the anticipated discharge of 5.99 cfs and <br />the design configuration provided by BRL that velocities will be in excess of 6 fps at <br />slopes greater than or equal to 13 %. Please include an additional design for the <br />segment of the West Diversion Ditch #1 that exceeds 13% slope. <br />BRL: West Diversion Ditch #1 above gob pile #4 has been partially constructed, as <br />approved by MR -132, at a 3.5% grade as previously noted. The alignment will <br />change as shown on Figure 2. Instead of terminating into the channel section <br />discussed above by DRMS, it will now terminate is channel segment "D ", which is a <br />stable ephemeral channel currently designed to handle a flow of 16.28 cfs. The <br />revised flow will be 17.55 cfs and an updated design is included as page EXH. 8 -11. <br />Because of West Diversion ditch #1 being re- routed, the disturbed area boundary will <br />increase by 0.51 acres. <br />16. Page App. B -42 indicates that the overall slope for the West Diversion Ditch #2 will be <br />6.5 %. This appears to be accurate for the overall ditch length, but also does not <br />seem to consider the steeper section (approximately 20 %) of the ditch for the last <br />-200' before the transition to the East Diversion Ditch. Please include a <br />supplemental design for the steeper segment of the West Diversion Ditch #2. <br />