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Environmental Protection Plan, Schwartzwalder Mine 15 -10 <br />monitoring wells, the detailed monitoring plan may be developed after well drilling and completion. The <br />wells will be monitored quarterly for the standard analytical suite for groundwater established for the site <br />(EPP, Section 12) and results will be submitted to DRMS and CDPHE. <br />The drilling is planned for late summer or early fall, 2011. The proposed schedule for permitting, site <br />preparation, well drilling, and well completion is shown in Table 15 -1. <br />(ii) Downgradient Bedrock Monitoring Wells <br />The downgradient paired bedrock monitoring wells will be located in the Schwartz Trend rocks, <br />approximately 900 feet from the mine. The proposed location is along the existing 4WD road near the <br />southeast corner of Cotter's property (Figure 15 -4), between the mine workings and Ralston Creek. The <br />proposed locations will be field verified and staked, prior to a contractor orientation and pre -bid meeting <br />for qualified drilling contractors. <br />Two paired wells are recommended to identify downward vertical gradients and any variations in water <br />quality with depth. Depending on accessibility and exact well location, the deepest well is expected to be <br />300 feet deep and the shallower well is expected to be 80 to 120 feet deep. A cross section along the <br />Schwartz Trend, showing the #2 and #3 mine shafts, Ralston Creek, the proposed monitoring wells, the <br />water level elevation of the mine pool, and an approximated potentiometric surface, is shown in Figure <br />15 -5. <br />The primary purpose of these wells is to determine water levels, water quality, hydraulic gradient, and <br />groundwater flow directions in bedrock. Water quality sampling will be performed using approved passive <br />sampling methods (such as Tedlar bag, diffusion samplers, SNAP samplers, HydraSleeve ®, or other <br />passive methods) because hydraulic conductivities are so low that unnatural gradients may be induced by <br />well purging and bentonite intrusion could occur. <br />(iii)Monitoring Well Construction Schedule <br />The proposed downgradient bedrock monitoring wells will require new disturbance to re -open a previously <br />reclaimed road. Contingent on the approval and the availability of a drilling contractor with a buggy - <br />mounted or track- mounted drill rig, the downgradient monitoring wells could be completed within six to <br />eight weeks after approval by DRMS. A proposed schedule for permitting, drilling, and completion of both <br />downgradient and upgradient bedrock wells is provided in the following table. <br />4109C.110510 Whetstone Associates di <br />