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DRMS Comment <br />Map G -3: Sediment Pond 2 <br />13. Only runoff volume calculations for the 100 -year design storm were provided. Please <br />provide runoff volume calculations for the 10 -, and 25 -year, 24 -hour design storms. <br />14. As the site is a DMO, any embankment fill is considered an EPF. Please reference <br />embankment material fill and compaction specifications on Map G -6. <br />15. Please provide hydraulic calculations for the emergency spillway. <br />SMO Response <br />The 10 -YR and 25 -YR runoff calculations have been added to Appendix 6 under the appropriate <br />stormwater basin (SWB -7). A reference to the embankment specifications on Map G -6 has been <br />added. The stage storage curve now shows the 10 -YR, 25 -YR, and 100 -YR runoff volumes for <br />the drainage area. Hydraulic calculations for the emergency spillways for all three sediment <br />ponds can be found in Table 6 -1 in Appendix 6. <br />DRMS Comment <br />Map G -4: Sediment Pond 3 <br />16. The stated storage capacity of Sediment Pond 3 is 0.2075 ac -ft. Section 4.5 (Exhibit G) <br />states the pond will store both the 10 -, and 25 -year, 24 -hour design storm runoff volumes. <br />However, the sum of the 10- and 25 -year runoff volumes (0.22 ac -ft) on the Stage - <br />Storage curve exceeds 0.20 ac -ft. Only runoff volume calculations for the 100 -year <br />design storm were provided. Please provide runoff volume calculations for the 10 -, and <br />25 -year, 24 -hour design storms. <br />17. As the site is a DMO, any embankment fill is considered an EPF. Please reference <br />embankment material fill and compaction specifications on Map G -6. <br />18. Please provide hydraulic calculations for the emergency spillway. <br />SMO Response <br />Map G -2 has been revised to accurately show the spillway elevations, and a reference to the <br />embankment specifications on Map G -6 has been added. The stage storage curve now shows the <br />10 -YR, 25 -YR, and 100 -YR runoff volumes for the area draining to the pond, and Exhibit G <br />Section 4.5 has been revised to explain that the ponds are designed to hold up to the 100 -YR <br />event runoff. Hydraulic calculations for the emergency spillways for all three sediment ponds <br />can be found in Table 6 -1 in Appendix 6. <br />