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<br />' <br /> These measurements and analyses will provide Lafarge, neighbors, and regulators with <br /> the first piece of the information puzzle. That is, what is happening to the groundwater <br /> level? This information can be reported in several ways. It seems the simplest means to <br /> convey the quantity and quality of water would be a narrative and a series of graphs and <br /> tables describing measured variables before and after dewatering, and whether the <br /> difference is statistically significant. This information could be distributed as needed to <br /> Lafarge decision-makers, neighbors, and regulators. Reporting will be discussed further <br />L in Section 4. <br /> This idea of water quality is an important one. It may be that a change occurs that is <br /> statistically significant but causes no measurable harp based on the definition of water <br />quality given above. In other words, a change in groundwater level may or may not <br /> result in a change in quantity or quality of water pumped for irrigation. It is necessary to <br /> have stakeholders find some agreement on what sort of change in quality results in a <br />" <br />" <br /> violation <br />. Often, this threshold is regulated by statute or government policy, but in this <br /> case it is most dependent on the concerns of neighbors. In this sense, a "violation" is <br /> really just a situation that it is agreed will instigate mitigation measures. <br /> With this in mind, the Following is a proposed framework for evaluating water quality for <br /> this situation. <br /> 1. It must be agreed that the pre-mining measurements are a baseline measurement <br /> of water quality. Previous changes to groundwater levels due to other mining <br />' operations or past dewatering efforts or natural causes cannot be accurately <br /> measured or mitigated as part of this monitoring program. <br />' 2. Before any mitigation efforts begin, a change in groundwater level or chemistry <br />must be shown to be significant. This means a change in water quality is <br /> consistent over time and not cone-time event. This will be determined by a <br /> "Tolerance Limit" approach, which specifies a range of measurements for each <br />well. If a certain percentage of measurements falls outside the specified range, <br /> this constitutes a significant change in water level or chemistry for that well. <br /> This method will be discussed in more detail in Section 3. <br /> 3. In the case of leach field protection, if groundwater rises to within three (3) feet <br /> of the surface, mitigation measures will be initiated. This is a public health and <br /> safety issue. However, the current intent of Lafarge is to reclaim the pit as an <br />' unlined pond. Therefore no upstream bulge should occur. This makes flooding <br /> of septic leach fields unlikely. <br />' 4. For irrigation wells and groundwater-fed ponds, each individual well or pond <br /> owner must report observed changes in pumping rates, pond water levels, quality <br /> of ground cover, or pasture land yield to Lafarge. Tf it is found that flow-adjusted <br /> groundwater levels have changed significantly in the area of concern, this will be <br /> considered a "violation". <br /> This framework includes both quantitative and qualitative elements. Measurements taken <br /> in the wells form the quantitative part. Observed changes in irrigation abilities, pond <br /> levels, quality of lawn cover, pasture yield, etc., form a qualitative assessment of <br />1 <br />' 4 <br />