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TCC Response <br />As previously discussed, Site 8 is one of several sites which has <br />both an in-stream and suspended staff gage in place. The first two <br />readings noted in your comment are recorded from the ISG (inside <br />stream gage), while the latter value is recorded from the suspended <br />staff gage, both of which have had rating curves developed. It has <br />been necessary in the past to record the ISG values only, or <br />likewise the OSG (suspended staff gage) only due to circumstances <br />in the field (such as the presence of beaver dams or vandalism). <br />Normally, both values are recorded in the field, but only a single <br />value may be entered directly into the database, which may <br />sometimes result in what appears to be an anomalous value. The <br />comments on the data pages for sites with both ISG and OSG values <br />will be modified in future reports'to clarify this matter, and will <br />hopefully address the issue. As the values reported for flow-rate <br />are correct, Table 30 has not been revised. <br />DMG Concern <br />3. Please reference the location of the data in the TCC permit <br />which demonstrates that mine discharge composes favorably with <br />predicted inflow rates. <br />TCC Response <br />As previously discussed, the primary data being referenced in our <br />comparison of discharge rates to inflow predictions are the inflow <br />predictions themselves, which are presented in Table C of the <br />permit exibit. As discussed, the stated predictions for the <br />overburden de-watering (without any credit from the model for the <br />minimal inflows observed along the fault) correspond very closely <br />with the observed discharge rates given a +~- 12 month variance in <br />the inflow projections due to market conditions. Permit pages <br />2.05-118 (h) and 2.05-118(i) reflect the slightly revised expected <br />case, which utilized data obtained for the update of the case <br />projection. Given that the inflow model was utilized primarily as <br />a general predictive tool, TCC feels that the observed discharge <br />rates compare extremely well with the inflow predictions (minus any <br />credit for fault inflows), and that the model has in fact performed <br />in accordance with the expectations of both TCC and the Division. <br />Should you have any questions or comments, please contact me at <br />your convenience. <br />Sincerely, <br />~,~,~ y~~~ ~ ~ <br />Marcus A. Middleton <br />Environmental Specialist <br />