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program. The Division does not expect volume or surface area requirement limits to cause any <br /> jurisdictional oversight by the OSE, but given the steep terrain, embankment heights might. <br /> Please review the OSE's Rules and Regulations for Dam Safety and Dam Construction, Rules <br /> 4.2.5.1 and 2 to determine if existing and/or upgraded embankments require Dam Safety <br /> oversight and provide a summary in your response for each EMP reviewed. <br /> Section 2.5.2 of the evaluation has been updated to include a review of each EMP against <br /> the OSE's Rules and Regulations for Dam Safety and Dam Construction, Rules 4.2.5.1 and <br /> 2. Table 2.10 has been added to this section to include a summary of jurisdictional dam <br /> status for each EMP. <br /> 3. ECOSA Toe Berm: The evaluation indicates CC&V believes the ECOSA toe berm should not be <br /> classified as an EMP. The Division disagrees for two reasons: 1) the potential for stormwater <br /> runoff from the ECOSA to have metals and low pH is significant based on water quality results <br /> from the ECOSA seep, and 2) runoff from the west side of the SGOSA is captured by DC-EMP-8b <br /> which reports to EMP-8b which is an EMP with a required design storage capacity of two times <br /> the 10 year, 24-hour storm runoff volume. Please reclassify the ECOSA toe berm as an EMP and <br /> provide the necessary design upgrades to the ECOSA toe berm to satisfy the two times the 10- <br /> year runoff volume criteria. <br /> The ECOSA toe berm has been reclassified as an EMP and associated design upgrades are <br /> included in the evaluation. <br /> 4. Geotextile use: Section 4.2 discusses using 8-ounce non-woven geotextile underlayment for <br /> riprap-lined channels. The Division's engineer's experience with riprap on non-woven geotextile <br /> is that on longitudinal slopes greater than about 10 to 12 percent, design peak flows wash the <br /> riprap right off the geotextile. In order to avoid maintenance after storms approaching the design <br /> storm, the Division recommends (but does not require at this time) using a granular filter under <br /> riprap for longitudinal slopes greater than 10 percent. <br /> The 8-ounce non-woven geotextile underlayment for riprap-lined channels detailed in <br /> Section 4.2 has been left as-is in the evaluation as Knight Piesold recommends this material <br /> as sufficient and a granular filter under the riprap is not required at this time. <br /> 5. Closinz Remarks: Section 5.0 attempts to summarize necessary upgrades to ponds, diversion <br /> channels and spillways, but is somewhat confusing. For example, channel DC-EMP 8a appears <br /> to be a newly required channel, but implies there upgrades necessary related to capacity and <br /> riprap. Also the use of the word "absent" is confusing. For example the channel DC-EMP 18N is <br /> followed by "absent", yet the Table 3.1 indicates it exists. Please provide a more thorough <br /> summary of what specific (e.g. non-existent channel requires full design; riprap not present, but <br /> necessary;pond inlet protection not present, but necessary; etc), if any upgrades are necessary <br /> for each structure. <br /> The Closing Remarks section of the evaluation has been updated per DRMS' request. <br /> 6. Drawinjzs 050 and 200: Previous EMP upgrades have let to violations related to affecting area <br /> outside the affected area boundary (specifically EMP 9a). As the current permit boundary is <br />