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7. At our meeting on July 1, there was some discussion regarding <br />whether the Pond 5A open channel spillway rock lining would need to <br />be replaced with graded angular riprap, in conjunction with the <br />refuse area drainage stabilization work. Susan Burgmaier of our <br />staff reviewed the pond design, and determined that because the <br />pond as designed would not discharge through the open channel <br />unless the 25 year event is exceeded, riprap replacement would not <br />be required. This determination is contingent upon verification <br />that the pond was constructed in accordance with the approved <br />design, including the two-level open channel spillway depicted on <br />Map SOA "RP-5A As Built", and the 3" trickle 'tube de-watering <br />device at an elevation 2.5' below the primary spillway as specified <br />in Illustration 6A. <br />8. We have several concerns with regard to the specifics of the <br />"grass lined channel" seedmix described on amended Page V-42, and <br />detailed in Table V-14 (amended Page V-44). First, it is <br />recommended that shrubs and forbs be deleted from the mix to be <br />used within the ditch channels. Second, Table V-14 is confusing <br />and internally inconsistent. At the PLS lbs/acre seeding rate <br />specified, the rate would be extremely high, 37 PLS pounds per <br />acre, and approximately 285 PLS seeds per square foot, for the <br />grasses alone! There is considerable extraneous information in the <br />table, and we recommend that it be simplified, and the seeding rate <br />reduced, as follows: <br />SPECIES <br />Intermediate <br />wheatgrass <br />Pubescent <br />wheatgrass <br />western wheatgrass <br />Green needlegrass <br />Junegrass <br />Total* <br />% OF MIX PLS PLS <br /> <br />------------ SEEDS/SQ.FT. <br />-------------------- LBS/ACRE <br />------------- <br />25% 8 4.0 <br />25% 8 3.5 <br />25% 10 4.0 <br />15% 4 1.5 <br />10% 3 .05 <br />33 <br />13.05 <br />* Total rate listed is for drill seeding, and would be doubled for <br />broadcast seeding. Bitterbrush, winterfat, and Utah sweetvetch <br />would be added at 1 pound PLS per acre each, for stabilization <br />plantings other than ditch channels. <br />The narrative on Page V-42 should be amended to correspond to the <br />revised table. <br />