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Total Iron, rng/l 6.0 <br />WET, Acute Lethality LC50>100% <br />While only pH and WET were tested specifically on a settled sample the other parameters (TSS, <br />SS, and Total iron) should be easily obtained through settling. Dissolved iron was tested with <br />results far below the effluent limit. Any addition to the dissolved iron value would be coming <br />from the suspended fraction of the Total thus subject to removal through settling. <br />Test samples of pH ranged from 7.47 to 8.00. Dissolved Fe ranged from 0.00 to 0.42. WET tests <br />were conducted twice with neither set showing any fatalities (passed). <br />The clarity of the samples upon only overnight settling eliminated our concern for being able to <br />meet the TSS and SS requirements. <br />The multi tiered system provides BME the ability to adapt and respond to changing conditions. <br />While not expected, if oils and grease become an issue it would be a simple fix to place a <br />containment boom across the first Dewatering Pond or spillway of the Last Chance Pond. <br />Similarly, if we encounter conditions where dispersant clays become an issue appropriate `Floc <br />LogsTM' could be placed in the entry or outflow of the first pond to improve settling. <br />Observations of local ponds and DP-1 Pond have shown a strong correlation between wetland <br />vegetation and clear water. Organic matter is known to aid in neutralizing the ionic charges which <br />often hold clay particles in suspension. While not seen as a necessary step in our treatment <br />process aquatic vegetation provides another level of insurance along with the obvious benefits to <br />wildlife. <br />The final "Last Chance" pond provides added protection from the initial flush and stormwater <br />flows prior to vegetation establishment. <br />8. Water flows by gravity over naturally gently sloping ground (overland flow). No ditches are <br />planned. The design utilizes the natural topography to convey the water. Berms may be used to <br />help direct and disperse flow if needed. Ponds will be constructed on grade and essentially in-situ <br />with inflow and outflow at or very near original elevations. No spillways are obvious in the <br />embankments because in-situ ponds do not need embankments. Soil removed during pond <br />excavation is piled next to the ponds to ease reclamation and to add freeboard. Water is allowed <br />to flow out of the ponds at natural ground level where soil is not stockpiled. Best management <br />practices will be used to disperse flows and stabilize subject areas as needed. It is expected that a <br />rapid vegetation response will occur resulting in robust grass waterways forming. Until that time <br />BMPs such as loose straw, riprap, jute mats, etc. will be used on an as-need basis to disperse and <br />slow overland flows. <br />9. You are correct that the heavy blue lines within the artificial wetlands represent the berms as <br />described on the text of Map 157. The final berm shown is to ensure that the system flows to the <br />Last Chance Pond. Overland flow is relied upon instead of ditches to reduce maintenance and add <br />diversity to the wetland structure. The intent of the system is to disperse flows within the confines <br />of the system as a whole and not to confine flows by way of channels. These overland flow paths <br />are expected to mimic more of the `wet meadow' type of wetlands over time. If a defined channel <br />was intended it would have been engineered and modeled. We did not see the need to model and <br />describe in detail overland flow through a wetland. Since we are not relying on the wetlands for <br />treatment we felt that it is not necessary or required that we provide the Division with <br />`assumptions' in its design beyond what was already provided. Please review the revised models <br />