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Drilling will be conducted using a truck -mounted rotary/core rig. Hole depth will range from 150 feet to 2,200 feet. <br />Cuttings will be flushed from the drillhole using air or air/foam until hole depth or conditions require the use of water <br />or drilling mud. Auxiliary equipment will include a small tracked -dozer, backhoe, pipe -truck, water -truck, personnel <br />vehicles, and a geophysical logging truck. <br />Drillholes on some occasions will require new roadwork. Necessary agreements from surface owners have been or <br />will be obtained prior to disturbance. Soil materials from pioneer roadwork, mud pits, and construction of drill pads <br />will be stockpiled for reclamation. Average disturbance areas are: drill pads 60 x 40 feet, mud pits 12 x 6 x 5 feet, and <br />roads approximately 20 feet wide. <br />Drillholes will be plugged and sealed with a combination of cuttings, bentonite compounds, and portland cement <br />slurry, consistent with State Engineer requirements. Plugging and sealing materials will extend from the bottom of the <br />drillhole to within ten feet of the surface. Drillholes encountering multiple aquifers or bedrock aquifers will be sealed <br />using a portland cement and/or bentonite plug extending 50 feet above and below the water -bearing zone(s) in <br />accordance with 43 CFR 3484.1(a)(1). All surface casing will be removed and/or cut off three feet below the surface. <br />An approved expandable plug will be placed ten feet below the surface when cuttings are used to backfill the hole, and <br />a cement slurry will be placed within three feet of the surface. Following plugging and sealing, drill -pads will be <br />reclaimed by grading the area to blend with the surrounding terrain and promote effective drainage, replacing <br />stockpiled soil materials, and reseeding with the following seed mix; <br />Western Wheatgrass <br />8.1 PLS/ac <br />Intermediate Wheatgrass <br />7.2 PLS/ac <br />Indian Ricegrass <br />2.7 PLS/ac <br />Drill -sites will be broadcast seeded and straw mulch will be applied and crimped -in. Proof of compliance will be <br />provided within 60 days after abandoning a drillhole or completing a specific drilling program approved by the <br />Division. Along with the Proof of compliance, MCM will submit a report detailing the following information: <br />• A brief narrative of how and why the program was conducted <br />• Name of drilling contractor and license number or drill and rig <br />• Location of the drillhole, as spotted accurately on a topographic map <br />• Surface elevation <br />• Drillhole diameter <br />• Drillhole depth <br />• Intervals where water was encountered during drilling activities <br />• Type of cement or other approval sealant used <br />• Amount of cement and volume of slurry mixture or other sealant used in plugging drillhole <br />Development drillholes may be temporarily secured for possible re-entry or future use prior to final abandonment. In <br />such instances, drillholes will either be cased or sealed to prevent possible aquifer communication as previously <br />described. Development holes will be surface -cased and cemented or grouted in all instances, and tightly capped to <br />prevent unauthorized entry or surface or subsurface water inflow. Protective barricades or fencing will be installed to <br />prevent damage to the portion of the casing protruding above the ground surface. If development drillholes are not <br />subsequently used for mine development purposes, they will be abandoned in accordance with the standard procedure <br />previously described. <br />Holes DDP-94-001 (Hole A94) and DDP-95-14 (MR 95-40) were drilled and completed as a monitoring wells, but <br />were never incorporated into the monitoring program, given the timing of cessation of active mining operations. On <br />completion of drilling and casing operations, required completion reports were submitted to the CDMG and both drill <br />sites were reclaimed consistent with the approved reclamation plans. The two wells remained in-place and were <br />capped to prevent access or contamination. Wells DDP-94-001 and DDP-95-14 will be retained for possible use as <br />monitoring wells in conjunction with any future mining activities, and will be plugged and sealed when no longer <br />needed in compliance with all applicable State Engineer requirements. <br />TR14-36 2.05-2.1 Revised 09/08/14 <br />