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<br />under all possible conditions. Slope stability is affected mainly by the steepness of the <br />slopes, the characteristics and strength of the embankment and foundation soils and the <br />seepage forces and pressures. In order to adequately address slope stability issues a <br />considerable amount of work is needed including drilling test holes through the <br />embankment and foundation and installing and monitoring piezometers. That degree of <br />effort is considered well beyond the scope of work needed to prepare the proposed <br />inventory. However, it is possible to perform a preliminary stability analysis using soil <br />samples from shallow hand-auger holes and based on observations of downstream surface <br />seepage. The proposed project includes this preliminary level of stability evaluation. <br /> <br />4. Spillway/Flood Hydrology - Except for transient maintenance-related issues such as <br />debris and ice accumulation, a long history of spillway adequacy can indicate some <br />degree of spillway secwity. Therefore, this is the lowest priority item and related aspects <br />of the proposed study will be limited to field observations of spillway conditions, <br />identification of spillway adequacy modeling previously performed by the Division of <br />Water Resources, and research of typical means used to identify spillways that are <br />susceptible to ice damming and effective means used to control ice damming. Future <br />investigations may pursue this aspect of the facilities at a more detailed level. If, at some <br />future point, it appears appropriate to pursue spillway and flood hydrology issues in a <br />more comprehensive manner, it would be best to evaluate the entire basin rather than <br />individual dams. This is because spillway considerations can be substantially impacted <br />by both upstream and downstream dams. For example, a small dam may not pose a great <br />breach hazard if a larger downstream dam could contain the entire capacity of the smaller <br />dam within its freeboard. On the other hand, a dam which has adequate spillway capacity <br />when considered by itself may pose a much greater hazard if the breach of an upstream <br />dam creates a cascading series of breaches in this dam and, perhaps, other downstream <br />dams. A comprehensive evaluation would likely consist of creating a flood hydrology <br />model of the entire basin that could be used to evaluate the impact of a wide range of <br />precipitation events. <br /> <br />5. General Dam Condition - Overall characteristics of the dam and appurtenant features <br />which are relevant to safety and serviceability will be observed and noted. <br /> <br />2 <br />