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Applicant's Response to Second Adequacy Letter Grand River Park Project, DRMS File M-2006-046 January 2, 2007 Page 16 In relevant part, the Martin & Wood modeling report notes that, [T]he predicted drawdown contours and water table elevations reflect the dewatering effects of the gravel pits alone and not the actual head contours at any given point. Pumping of the nearby wells, as well as variations in climate (dry or wet), and changes in river flow and stage conditions will also affect water table levels in the area... The model, as constructed, is classified as a "difference" model reflecting only the impacts to the system resulting from the dewatered pits. This is an accepted methodology for such determinations, especially, and as is the case in this study, where limited or no data are available on other stresses known to be affecting the system. The predictive aspect of the groundwater model is clouded by the complexity of the system, in which the effect of the gravel pit alone must be considered relative to a host of other dynamic variables. While it is reasonable to consider drawdown potential as a contingency for planning purposes, the results of the Martin & Wood model should not be taken to predict any specific result under actual environmental conditions. The same report goes on to note, regarding wells, that, [T]he relatively small amounts of predicted drawdown due to dewatering should not prevent the majority of the deeper wells from continuing to pump as in the past, though pumping costs may increase slightly. For those wells incurring greater levels of drawdown, especially those reported to be shallower, there may be significant impacts on their ability to continue to pump as in the past. This reference regarding wells is the only conclusion in the modeling report that could be taken to represent a significant, adverse impact to a specific resource. There is some historical uncertainty regarding the accuracy of well registration records (e.g., reported shallow wells may in fact be deeper or may have been improved since the well record was created), but, above and beyond record- keeping matters, the report notes that there "may" be significant impacts, which is again something less than a prediction and not necessarily "adverse" in the sense of injury to protected rights. For example, if a well owner has historically pumped at yields higher that the well's decreed right, does it constitute an adverse impact if the well owner must share some of the aquifer's productivity with reduced pumping rates that still yield the decreed amount? Well viability will be affected not only by drawdown potential but by age and efficiency of pump equipment, deterioration of well casings, etc, which possibility must be addressed by appropriate investigation of any alleged mining impacts.