2010-01-22_REVISION - C1981008 (2)

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C-1981-008 PR-06 PAR 22-Jan-2010 Page 10 of 26 Much of the information presented for the Pond 012 re-design appears to be inconsistent and it is unclear what the revised SEDCAD runs are attempting to demonstrate. If WFC is proposing to change the spillway configurations then this should be clearly explained and the SEDCAD demonstrations need to reflect accurate information. A new As-Built Certification would be required if the pond configuration or spillway elevations are changed. Please clearly explain why Pond 012 is being re-designed and clarify the discrepancies noted in the revised SEDCAD demonstrations as described above. 25. Pond 013 is also being re-designed because it will receive increased drainage due to WFC's decision to eliminated Pond 010. With this revised design WFC demonstrates that the as built pond is sufficient to handle the revised drainage area. Spillway elevations remain the same and the pond configuration is not changing therefore WFC did not resubmit the As- Built Certification map but did submit a revised Engineering and Hydrologic Design and As Built SEDCAD and SurvCad hydrology calculations. Only one minor inconsistency was identified on the existing approved As-Built. The emergency spillway elevation is incorrectly labeled on Map 2.05.3(3)-18 as 5657' and should be 5557'. Please check this elevation and make the necessary correction to Map 2.05.3(3) -18. 26. On page 2.05.3(3)-6-34 of the original Pond 013 Design Calculations, permit text regarding manual operation of the pond was taken out of the permit document with PR-6. This appears to be the case for the Pond 011 Design Calculations as well. This language was a permit condition that was placed on the permit application package with the last Midterm Review and more recently with TR-56. Please reincorporate this language (see strike out on page 2.05.3(3)-6-34) into the Engineering and Hydrologic Designs for Ponds 011 and 013. Otherwise provide a detailed explanation why this permit language should be removed from the permit document. 27. Pond 015 is a new pond design submitted with PR-6. This pond is designed to capture and contain without discharge the 100-year24-hour precipitation event. The operator has successfully demonstrated that the temporary impoundment will safely control the design precipitation event. However, the operator has not demonstrated how the water will be removed. In accordance with Rule 4.05.9(2)(e) provide a demonstration that the water from the pond will be safely removed in accordance with current, prudent, engineering practices. Attachment 2.05.3(3)-20 should be certified by a registered professional engineer. 28. Inconsistencies were noted in Attachment 2.05.3(3)-20 regarding principal and emergency spillways for Pond 015. The text on pages 2 and 6 of the attachment indicate that there is no embankment that could fail and no spillways are required. However, on the Stage Storage Curve (page 9), the top of structure is labeled as 5572.00' and principal and emergency