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• a <br />narrow point in the stream relative to the downstream station, and the fluvial gradient is <br />steeper in the upstream station. Both the width of the stream and the gradient at the <br />upstream station work together to give the stream energy and, thus, more sediment carrying <br />capacity. Hence, the fine particles in stream load are carried away. The vegetation around <br />the upper station is relatively dense forest vegetation, whereas the downstream vegetation <br />consists of relatively sparse shrub cover. The upstream sampling area flows, more or less, <br />over large boulders and bedrock whereas the downstream station flows over generally fine, <br />friable, alluvial and colluvial valley fill material. <br />The most striking oversight in Mr. Jaquez' selection of sampling locales is the choice of a <br />beaver pond for the downstream station. Not only is the pond collecting sediment, it is <br />providing an area of quiescence where clay particles will stay suspended, probably for <br />several days. Clay, once suspended, will remain suspended for a couple of days, even under <br />very still conditions. <br />Thus, one should be able to conclude without even a single measurement t:tat until all of <br />the mitigating factors are considered, one cannot adequately test the mine's contribution to <br />the sediment load. It is obvious that the County Road and especia]ly tha: uncontrolled <br />drainage from the dry washes passing from the north are the major sediment contributors. <br />The mining operations are contributing a measureable amount of sediment, ;tnd the failure <br />of the sediment control system during the storm that preceded the Board's visit certainly <br />contributed to the sediment load. But overall, as seen in our various inspections, the <br />sediment containment berms around the various ore and topsoil and waste rick stockpiles, <br />the very large berms along the mine roads, the perpetual road spraying along the county <br />road, the county road maintenance that the mine contributes, and the sediment diversion <br />and control structures that have worked adequately during previous less severe storms, are <br />containing the sediment as planned. The mine is not a zero impact site with regard to <br />sediment control, but the sediment contributions from the mine compared .vith the other <br />non-mine contributions have been over-stated by the Parties to the April B~>ard Action. <br />Finally, Jim Pendleton has offered the Parties, through Nora Jaquez, :he Division's <br />assistance in reviewing the evidence gathered by Mr. Jaquez. If I can be of service in that <br />capacity, I would be pleased to help. <br />cc: Jim Pendleton Berhan Keffelew <br />Jim Stevens Larry Oehler ~/ <br />