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relative elevation for each pond prior to construction. Therefore, the original bottom of channel elevation cannot be tied to the mine survey grid used to obtain the as-built surveys. Also, Title 35, Article 49 states that if the pond does not exceed the 2 acre feet and a 5 foot vertical height, a conduit drain for the pond is not required. While the vertical height cannot be obtained, it is assumed that since none of the ponds being considered exceed 2 acre feet, the conduit drain is not required. All of the ponds being • ~~ considered were constructed without a conduit drain. Finally, the SCS provides spacing guidelines that should be followed. However, these spacing guidelines are not stated as definite requirements. Therefore, in order to avoid the removal of a large number of ponds these guidelines have not been included as one of the criteria in evaluating the ponds. I feel this is an issue which CYCC should address with CDMG to insure there is no confusion regarding this matter. The spillway information shown on Attachments A and B are transferred from ACZ's results shown in Attachment D. You will probably notice that there are several ponds for which ACZ's freeboard calculation do not equal the "After S.W. Modification Freeboard" shown in Attachment C. There were several ponds in which ACZ used a slightly different top of dam elevation than was used in Attachment A and C. Nevertheless, regardless of which freeboard is used, the freeboard after modification will exceed the State Engineer's 2 foot minimum requirement. Attachment E provides a pond-by-pond analysis in which the repairs and modifications are described for each pond. Also, any cracks in the embankment that were observed during the inspection are noted in the analysis. Since I am not familiar with the actual construction of the embankments, I am uncertain as to the cause of these cracks. As an initial remedy CYCC may want to blade over the cracks to prevent water from entering the embankment. The embankments can then be monitored for the reappearance of the cracks. You will note that the majority of the ponds require the spillway to be extended 20 feet below the toe of the dam and erosion control material placed in this extension. CYCC may want to discuss this issue further with CDMG in order to better define the toe of an excavated pond. It may be possible to eliminate extending the spillway at some of the ponds depending on where the toe is defined. best of my knowledge d belief. w Patrick K. Sollars CO P.E. 29172 I, Patrick K. Sollars do hereby certify that the information presented in Attachments A, B, C, and E are true and correct to the 9kr193 ,,,,,,,,~~~~„~,,,,,,,, c ~G Date \\~~~~`~pGO ~ G/ ~~ c' '` ,, •, J~jf,G' v ::~''~~v ns~< ,per. r ;z .. ~ .. ~•~~ ~ ~ :~~4,. ~''~..,S~~NAI ~N..``~: