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Albert Frei & Sons, Inc. Page 2 <br /> Hatchery Pit Permit # M-2014-043 <br /> Revised 1/7/19 <br /> The location of the Bull Seep and Thornton' s slurry wall will limit the <br /> amount of ground water shadowing along the west side of the mine. The Bill <br /> Seep will recharge the groundwater and limit the mounding behind the slurry <br /> wall on the Thornton site will keep the groundwater elevations constant on <br /> this site. <br /> The backfilling along the entire north side may have already limited water <br /> flow thru this area and is forcing the water to back up on this site. That <br /> may be why there is a constant flow of water thru the lateral drain that runs <br /> along the north side and along the base of the hill. This may also explain <br /> why the water elevation of the old gravel mine lake appears to be higher the <br /> it was prior to that area being filled. On the other hand if it has <br /> restricted flow thru that site it has not has a significant impact to the <br /> east . <br /> Most of the existing lateral ditches and small ponds will be removed as <br /> mining progresses . They now serve to direct the seepage water and surface <br /> waters around the property and back to the western drainage. The existing <br /> ditches will be rerouted to more direct routes and new ones will be installed <br /> around the mined areas to preserve the historic flow of the water. On the <br /> north they will be directed into the existing lake so the water returns to <br /> the system. On the south a lateral ditch was built along the south side of <br /> the slurry wall so water can be diverted back to the Bull Seep drainage. <br /> This ditch also acts as a surface drain for groundwater that may backup along <br /> the slurry wall in that area and will carry the flow from the French drain to <br /> Bull Seep. <br /> Groundwater Monitoring Data Analysis <br /> As the data is collected, it will be recorded in a spread sheet and graphed <br /> to establish the baseline data that can be used to determine what if any <br /> impacts the slurry wall and compacted liner are having on <br /> the groundwater table. The data collected to date has allowed us to <br /> determine what the new trigger point elevations are. These elevations <br /> determine what actions are needed. Data collection will continue on a <br /> monthly basis until 13 consecutive samples have been collected and then go to <br /> a quarterly basis until 2 years after the liners are complete. From then on <br /> till reclamation is complete the monitoring will be done once a year. The <br /> data collected in the first 3 samples were used to determine the elevations <br /> of the compacted liner and French drain elevation in Stage 2 as discussed <br /> above . Future data will be used to determine if a trigger point has been <br /> reached and what actions will be needed. <br /> Baselines and Trigger Points <br /> The baselines for each well have been determined by taking the high and low <br /> elevations of each well from the data collected in the first 7 samples. The <br /> proposed trigger points have been determined to be elevations that are <br /> greater than two (2) foot above the highest elevations and/or less than one <br /> (1) foot above bedrock elevation in the monitoring Wells 1, 2, & 3 . Based on <br /> the data collected it appears that mounding may not be a problem since there <br /> is none apparent from the filling done on the adjoining property. In <br /> addition, the natural groundwater, pre dewatering, elevations in Stage 2 <br /> averaged 5079 . 8 or approximately 30 feet below the surface . <br /> The following table shows the proposed trigger elevations for each well now <br /> that site specific information is available. On Stage 1 the trigger point <br />