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<br />146. Rule 4.05.3(3) requires Division approval to use concrete lining in fill ditches. The <br />Division is concerned about the long term integrity of a concrete lining. Cracking and <br />breakdown of the lining would most certainly lead to piping, undercutting, and erosion. <br />Concrete spillways, where periodic flows have occurred, have shown a perpensity to <br />develop this problem. A combination of riprap and vegetation would seem to provide a <br />more stable, long-term channel and would likely accommodate flows without serious <br />erosion problems. Please consider alternative channel linings other than shotcrete for <br />permanent diversions. <br />147. Please include some text discussion on how adequate information on pond embankment <br />foundation conditions will be gathered and analyzed as required by Rule 4.05.6(11)(a). <br />Also include in this discussion the compaction parameters for pond embankments. <br />148. Embankment crest elevations were compared to full flow emergency spillway crest <br />elevations for all ponds detailed on EX15-11. All ponds were in compliance with the 1 <br />foot minimum freeboard expect Fill 5 pond. SEDCAD+ information was different than <br />the information presented in the pond schedule. Please review and correct as necessary. <br />149. Middle Jeff, Fill 2, I~il] 5, and Fill 8 ponds do not meet the minimum top width required <br />by Rule 4.05.6(I1)(h). Additionally, inconsistent top of embankment information was <br />found between the figure and the pond schedule for Fill 2 and Fill 5. <br />150. Due to the nature of some of the colluvial materials observed at this site, the Division will <br />require soil classification and gradation information required by Rule 4.05.6(1 l)(i) for <br />pond foundations. <br />151. Upper Jeff, Middle Jeff, Fill 2, Fill 3, Fill 5, and Fill 8 ponds all need a demonstration <br />of a minimum safety factor of 1.5 and a seismic safety factor of 1.2. Other ponds require <br />a safety factor of 1.3. <br />152. On the 100 year ditch table, the depth and width values are reversed for Fills 1, 2, and <br />3. <br />153. Ditch flow directions should be indicated for Fill ditches. <br />154. Ditches DS1A, DS2A, and DS3A are proposed earthen ditches but each has significant <br />lengths of 35% slope. How will these sections be handled as far as channel lining? <br />155. Ditch D21 discharge is represented as 23.38 in the table but should be 28.38. <br />156. DS3B should be 25.45 in the table and for D53 the discharge value should be .58. <br />157. For bills, Figure EX15-12 shows D52-D57 but the SEDCAD run and the table show D51- <br />D56. Which is corcect? <br />158. For riprap ditch section, please describe the filter layer that will be used for the various <br />