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<br />Division encourages SCC to consider lesser topsoil replacement thicknesses for these <br />areas. <br />Tab 7 <br />17. SCCs explanation of why the annular or bottom seals of the referenced wells are <br />6f: believed to have failed is adequate. However, in reviewing the well completion reports <br />t6tPl to verity SCCs explanation, the Division discovered that many (14) of the monitortng <br />wells appear to have been improperly completed. That is, no bentonite seal or packer <br />was pplace between the cement grout and the filter pack. The wells in question are: <br />YSALl, YSAL2, YSAL3, YSAL4, YSALS, YSAL6, YSAL7, YSAL10, YSALl 1, YSAL12, <br />YSAL13, YOV1, YOV8 and YW7. <br />Of the above wells, otrly YOV1 and YW7 were mentioned by SCC as having rendered <br />questionable data. SCC should explain how (or if) the integrity of the filter pack was <br />maintained in these wells without a bentonite seal or packer to prevent cement grout <br />form clogging the filter pack. Interestingly, reference to Table 7-4 (page 11) shows that <br />the wells with improper completion indicate significantly greater saturated aquifer <br />thickness than the wells with proper completion. How does SCC relate its estimate of <br />saturated thickness with monitoring well completion? <br />18. CDMG is currently reviewing. <br />~~"20. See comment #I8. <br />Tab 13 <br />27. CDMG requested that SCC revise curve numbers listed in Table 13-i. <br />~~ a. SCC stated that Rock Outcrop has been assigned a curve number of 98. Please <br />revise Table ]3-1 accordingly. <br />o~ b. SCC declined to revise the curve numbers assigned to paved roads, since "the <br />roads at Yoast are not paved." Regardless of whether there currently are paved <br />roads at Yoast, the accepted value for paved roads would be 98, since they are <br />impervious. If SCC does not have or plan to have paved roads at Yoast, they <br />could be removed from the table. 1f SCC would like to leave paved roads in the <br />table, a curve number of 98 should be assigned. Please revise Table 13-1 <br />accordingly. <br />~'.. 28. SCC stated an agreement to use precipitation values suggested by the Division. Please <br />revise Page 13-1-2 to reflect the increased precipitation values. <br />31. SCC indicated that documentation of landowner consent to retain haul roads would be <br />`~Q sent to the Division by March 15, 1995. As of this date, the Division has not received all <br />of the necessary documentation, and will therefore request that SCC remove reference, <br />on page 22 of Tab 13, to permanent roads. <br />~i 36. We have not yet received a response to this concern, which regarded temporary <br />stabilization measures for ditches which will rely on vegetation for stabilization. <br />g~ 38. a. SCC indicated that the Pond 10 watershed was remodelled using a curve number <br />~~ fnU.tC.ty of 85 for pit areas, as was used by CDMG. We used the curve numbers of 85 and <br />52 to illustrate the change in runoff when the watersheds were subdivided as <br />~R~~ ~,$C~ opposed to using weighted averages. CDMG did not mean to suggest, nor do we <br />p~5~tiktsa}'~' advocate the use of a curve number of 85 for pit areas. Please revue the model <br />using a curve number of 94 for topsoil stripped, pit, and spoil areas. <br />