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groundwater within the lower zone monitoring well (situated down gradient of the tailing impoundment <br /> facility)may be indicative of a compromised liner system;and,as such,Venture again proposes to increase <br /> the frequency of monitoring from quarterly to once per month until such time that liner system certification <br /> (or facility closure)is achieved. In this manner,if ground water were to be detected in the lower monitoring <br /> well, Venture would be able to provide timely notification to the Division and respond accordingly in a <br /> significantly more expedient manner over the duration of the planned corrective action. We view this as <br /> but one component of a proactive corrective action plan, and accordingly request Division approval to <br /> implement this change. <br /> Venture has reviewed the November 19, 2015 Inspection Report relative to the Division's concerns about <br /> monitoring well construction. In that Report, the Division expresses concern that the non-rigid 2-inch <br /> diameter HDPE pipes extend approximately six(6) feet above ground in an unsupported manner, and as <br /> such may be subject to: (1)potential damage; and, (2)an inability to obtain a representative groundwater <br /> sample. <br /> In order to address this concern,Venture has installed(vertical)4x4x8 redwood posts embedded 2 feet into <br /> the ground at the grouted collar of the borehole. <br /> Venture acknowledges receipt of the approved sampling protocol(denoted as Page 30 of 37;as attached to <br /> the November 19, 2015 Inspection Report) and commits to full adherence with same. A copy of the <br /> approved sampling protocol is attached hereto. In addition,Venture commits to retaining an independent <br /> third-party consultant to conduct the sampling, maintain sample custody through delivery to an analytical <br /> laboratory (if samples are obtained), and ensure that analytical results are reported directly to Venture, <br /> whereupon Venture will provide same to the Division. <br /> Per the Division's request, Venture also attaches hereto copies of both the up gradient (designated as <br /> "upper")and the down gradient(designated as"lower")well construction reports(which are also provided <br /> in Exhibit F to DRMS Permit No. M-2009-076); well construction details can be summarized as follows <br /> [Note: Both boreholes/monitoring wells were completed on April 1, 2010; no free water was observed at <br /> any depth interval nor subsequent to completion]: <br /> Upper Monitoriny-Well(Total Depth 20 ft.) <br /> Well Permit No.: 282789 <br /> Borehole 2-3/8"diameter(nominal): 0 ft.to 20 ft. (rock drill) <br /> Profile: Weathered granite(gravelly) oft.to 1 ft. <br /> Weathered granite(boulders) 1 ft.to 8 ft. <br /> Granite(bedrock) 8 ft.to 20 ft. <br /> Plain Casing: 0 to 3 ft. 2"diameter solid HDPE* <br /> Perforated Casing: 3 ft.to 20 ft. 2"diameter perforated HDPE* <br /> 'Note:The well log erroneously indicates 2-3/8"diameter casing;however,2"diameter HDPE was utilized. See also Permit M-2009-076 Exhibit <br /> T—Environmental Protection Plan(Page 5)for well construction detail. <br /> 6 <br />