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Page 3 of 9 <br />The Division has no further concerns. An engineer's certification was provided in the submittal dated <br />November 29, 2011. <br />4. A) There does not appear to be a discussion in the permit application concerning the construction <br />methods that will be used for the three sediment ponds. Rule 2.05.3(4)(a)(ii)(B) requires construction <br />specifications for the sediment ponds in order to ensure that the factor of safety has been met. Please <br />revise the permit text, perhaps in Section 2.05.3(4) or Appendix 2.05.3(4) -1, to include a description of <br />the construction techniques that will be used for building the sediment ponds, pond embankments and <br />pond discharge structures. <br />The Division has no further concerns. The November 29, 2011 submittal contained a revised Appendix <br />2.05.3(4) -1. <br />B) Please add a discussion in the permit application as to whether any of the proposed sediment ponds can <br />be classified as having Class B or Class C dams, as defined in the U.S. Department of Agriculture, Soil <br />Conservation Service Technical Release No. 60 "Earth Dams and Reservoirs ", October, 1985. If any of <br />the sediment ponds can qualms as having a Class B or Class C dam, please revise the permit <br />application to demonstrate compliance with those Rules which apply to Class B or Class C dams. <br />The Division has no further concerns. In the submittal dated November 29, 2011, Appendix 2.05.3(4) -1 <br />was revised to show that all three ponds have Class A dam embankments. <br />C) As required under Rule 4.05.9(8)(a) or (b), please revise the permit application after construction of the <br />three sediment ponds to include the appropriate geotechnical demonstrations that the applicable factor <br />of safety required under Rule 4.05.9(8)(a) or (b) had been achieved for each sediment pond <br />embankment <br />The Division has no further concerns. In the submittal dated November 29, 2011, Appendix 2.05.3(4) - <br />2A was provided. However, the operator must ensure that the assumptions made in the report are <br />consistent with what is actually done in the field. <br />D) Appendix 2.05.3(4) -1, "Arcadis Report on Sediment Control ", contains cross sections for the three <br />sediment ponds. The cross sections show that ponds NHN -001 and NI-IN-003 will have 10 foot wide <br />embankment tops. However, the cross section for pond NHN -002 shows that it will have a 5 foot wide <br />embankment top. The Division is concerned, especially since a public road is adjacent to the length of <br />the pond, that such a narrow embankment may not be stable enough to achieve the applicable factor of <br />safety. The Division requests that the permit application designs be revised to show that the <br />embankment top width for pond NHN -002 will be at least 10 feet. <br />The Division has no further concerns. Appendix 2.05.3(4) -1 was revised in the November 29, 2011 <br />submittal to provide for 10 foot wide embankment tops on all three sediment ponds. <br />E) The proposed sediment pond embankment heights, measured from the pond bottom to the emergency <br />spillway bottom, are listed in Table 3 and shown on the cross sections, in Appendix 2.05.3(4) -1. The <br />proposed embankment heights for ponds NHN -001 and NHN -003 are less than 10 feet but for pond <br />NHN -002, the proposed embankment height is 11.5 feet. Rule 4.05.9(6) requires a foundation <br />investigation for those pond embankments that exceed 10 feet in height. Please provide the foundation <br />investigation required under Rule 4.05.9(6) or lower the height of the pond embankment for NHN -002 <br />to 10 feet or less. <br />