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PERMIT #: M- 1983 -067 <br />INSPECTOR'S INITIALS: TOD <br />INSPECTION DATE: August 14, 2014 <br />Mr. Zigan stated in his complaint of August 4, 2014 that the current water level in Zigan Lake is elevated above <br />the historical levels. The complaint raised concerns about possible damage to structures around the lake. The <br />complaint explained that increased lake levels have prevented the lake owners from fulfilling their surface water <br />augmentation responsibilities with the Division of Water Resources. <br />Inspection began at Andy Zigan's home which is located next to Zigan Lake. The inspection consisted of a <br />visual examination of Zigan Lake and a discussion of the ongoing issues detailed in the email complaint. The <br />inspector observed approximately 6 to 12 inches of water over the top of a vault located in the lake (see photo <br />1). The vault houses the inlet pipe for the gravity drain. The top of the vault is at approximately 5021.37 feet in <br />elevation. Six to twelve inches of water over the top of the vault results in a lake level between 5021.87 feet to <br />5022.37 feet. The observed lake level is approximately 7 feet higher than the target lake level detailed in TR- <br />04. <br />Following the investigation at Zigan Lake, the Division visited the Stagecoach Pit site to observe the flow <br />through the gravity drain where it drains into the infiltration gallery (see photo 3). The Operator's <br />representative estimated that there were roughly 2 feet of water in the infiltration gallery above the elevation of <br />the outflow pipe of the gravity drain. <br />Following the investigation at the Stagecoach Pit the Division drove through the Worthing Pit (DRMS Permit <br />M- 1977 -526). The inspector observed standing water in a trench and in an abandoned channel of the South <br />Plate River that are located on the site. The trench was excavated in order to reduce the elevation of <br />groundwater in the area located upgradient from the backfill of fines at the Worthing Pit (see figure 1). The <br />trench drains into the abandoned channel. The Operator's consultant believed that the water in the abandoned <br />channel was 6 to 7 feet deep. During the inspection, water movement was barely detectable through the length <br />of the trench and the abandoned channel. Flow appeared to be constricted were the haul road crosses the <br />abandoned channel (see photo 4). <br />CONCLUSION <br />Based on observations made during the inspection and the review of groundwater monitoring data in the area, <br />DRMS believes the slurry wall that surrounds Stagecoach Pit (operated by Albert Frei and Sons), in conjunction <br />with the slurry wall that surrounds the Pit 29 (operated by Brannan Sand and Gravel), can be expected to create <br />a significant constriction in alluvial groundwater flow. The constraints on groundwater flow can be expected to <br />cause groundwater mounding between the two pits. These constrictions in alluvial groundwater flow have <br />resulted in elevated lake levels in Zigan Lake. Groundwater that does flow between the slurry wall of <br />Stagecoach Pit and Pit 29 is being further mounded where it encounters the fines that were backfilled in the <br />Worthing Pit (operated by Albert Frei and Sons). DRMS believes this is a problem for failure to minimize the <br />disturbance to the prevailing hydrologic balance and will be cited as a problem in this inspection report. <br />Page 4 of 7 <br />