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<br />4) No stability analysis was done of the drainage tiles, as mentioned in the previous Technical <br />Adequacy Review. Please submit a stability analysis of the 10' proposed setback, or an <br />agreement with the structure owner that allows excavation within 200' of these structures. <br />5) Case 5 Mining Conditions -Fish Hatcheries -does not state whether or not there are any <br />unlined ponds, lagoons, or nearby holding facilities which lie within 200' of the excavation <br />face. If any unlined structures holding water fall within the 200' minimum setback, they <br />should be included as water surfaces in the slope stability analyses, and the effects of mining <br />on their stability should also be analyzed. <br />6) Fences qualify as permanent structures that must be included in geotechnical stability <br />analyses if the structure owners perceive them as `valuable', in accordance with Rule 6.4.19 <br />of the Construction Materials Rules and Regulations. If a letter from the landowner stating <br />that [he structure has no significant value can not be obtained, then the Operator is reminded <br />that the residential setbacks must apply [o all structures which the landowners wish to be left <br />undisturbed. <br />7) In Case 4 Mining Conditions -Surrounding private homes, it is stated that typical foundation <br />loading (3000psf) has been added to the stability model for these cases. Please evaluate these <br />cases for site-specific conditions, including frame and brick houses, and cite the sources of <br />these loading values. <br />8) No analyses were done under pseudo-static conditions. Please analyze these scenarios using a <br />seismic factor of 0.05, to evaluate slippage under these conditions. <br />9) Slope stability analyses for the final .unlined, reclaimed slopes of Cells 1 and 5 were not <br />included. Please submit analyses of the stability of these embankments with regazd to critical <br />structures. <br />10) The phreatic surfaces assumed for these analyses aze inconsistent with the soil borings taken <br />at the site and included in the two geotechnical evaluations done by Empire Laboratories and <br />Terracon. The average phreatic surface along the northern boundary of the site is consistent <br />with that used in Case 1 for the west side of the site (Empire Laboratories analysis), but in all <br />other cases, [he phreatic surface is much closer to the surface than that used in these stability <br />analyses. Please re-analyze all cases with the appropriate worst case scenario water levels, <br />using the values noted in the geotechnical evaluations. <br />11) It is assumed that the consistent use of the O.SH:I.OV slope in these analyses constitutes a <br />commitment to refrain from excavating the slopes at a steeper angle at any time. Please <br />confirm this in writing. If this condition of your permit is ever changed, the setback <br />requirements must be re-evaluated at that time, and the Operator is reminded that failure to <br />comply with this condition would constitute a serious violation of the permit. <br />12) It is also assumed that the analyses of the western and eastern boundaries, in which the <br />maximum depth of the excavation is 22 feet, also constitutes a commitment to refrain from <br />