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approximate a water table occurring at about 5 -10 feet below grade at these locations. River <br />boundaries were assigned along the Poudre River and Greeley Canal with head boundaries slightly <br />lower than surrounding land elevations. The Poudre River head boundary ranged from 4788 to <br />4815 from north to south. The Greeley Canal head boundary ranged from 4792 at the eastern model <br />boundary, to 4811 where it connects with the Poudre River. <br />1.2.3 Model Results Discussion <br />Ditullio: Computed baseline water table elevations ranged from 4805 to 4811 with southerly <br />flow. Observed elevations ranged from 4802 to 4814 (Ref. 1) with measurements indicating_ <br />southerly flow with some localized easterly flow toward Greeley Canal. The model is shows <br />localized flow away from Greeley Canal (i.e. losing stream). ream). Groundwater flow toward the site is <br />conservative for predicting the effects of a liner, because a source of water toward the liner would <br />result in the prediction of higher mounding_ <br />Veldman: Model- calculated baseline water table elevations ranged from 4797 to 4805 with <br />southerly flow. Measured elevations ranged from 4782.9 to 4801.8 (Ref. 2) with elevations <br />suggesting a southerly flow direction. The measured water table near the pond at Veldman (elev. <br />4782.9 at well TH -7 ) is appreciably lower than calculated in the model. The lower water table may <br />be at least partially associated with the pond at Veldman where the following may be occurring <br />groundwater loss to make up for excavated solids volume; evaporation; and dewatering. No <br />groundwater elevation data is available downgradient to confirm the natural water table gradient. <br />However, pond effects appear likely. The regional topographic grade is about 0.2-0.25% dipping <br />south. The local gradient at Veldman using the TH -1 measurement is 0.5 %. In the predictive <br />model with liner, the predicted change in water level should be interpreted as relative to conditions <br />with no water loss effects initiallv. <br />1.3 Groundwater Monitoring and Mitigation Plan <br />1.1.11.3.1 Purpose <br />This Groundwater Monitoring and Mitigation plan has been developed in support of Martin <br />Marietta Materials (MM) Permit Amendment Application to the Colorado Division of <br />Reclamation Mining and Safety (DRMS) M- 1979 -191 112 Permit. The 112 Permit Amendments <br />is being submitted to revise the reclamation plan to Developed Water Storage and to revise the <br />Permit Boundary for the Three Bells Property. <br />This Plan addressed the actions developed by MM that would be implemented should adverse <br />groundwater conditions develop during site reclamation as lined below grade reservoirs. <br />1.3.2 Background <br />The Three Bells Mine is owned by River Bluffs Ventures, LLC and operated by MM. The <br />mine property is located approximately one half mile north and three miles west of Windsor, <br />Colorado, in Larimer County. The Affected Land is located in Township 6 North, Range 68 <br />West of the 6`h Principle Meridian, in Sections 11, 12, and 13. <br />