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The purpose of re- establishing the portal and rehabilitating the drift (if needed) is to enable CBCI to <br />inspect the underground workings as part of evaluating the viability of re- opening the mine for <br />production. <br />Re- establishing the portal will require the following steps: <br />1. temporarily stabilize the side slopes that are in front of the collapse into benches parallel with the <br />track and drift <br />2. excavate collapsed soil and other debris lying on the existing track that leads into the 14L drift <br />3. excavate and bench, through to bedrock, the collapsed slope that currently covers the 14L drift <br />4. grout (or epoxy) split set bolts and stabilizer bar into the face of the resulting highwall above the <br />newly exposed drift for temporary stabilization <br />5. fasten structural supports (depending on conditions: steel sets, steel plate, or tunnel liner) beneath <br />and on the face of the exposed bedrock (see Attachment E for an example of the structural <br />supports that may be used) <br />6. replace damaged track in the previously collapsed area as necessary <br />7. extend the structural supports approximately 50 to 75 feet northeast, through the excavated trench <br />8. backfill the structural supports up to 8 feet high using <6" material stacked in 24" lifts between <br />geotechnical fabric to distribute loading <br />9. above 8 feet, backfill with the remaining excavated material (screening for <6" is no longer <br />necessary) and compact /grade the top of the backfilled surface to conform with the undisturbed <br />slope <br />10. for stabilization of the backfill slope, stack large boulders at the toe of the backfill slope (as <br />needed) <br />11. scarify and seed the disturbed soil that was either placed as backfill or disturbed by excavation <br />(see Section 6.0 for the seed mix and rates) <br />12. weld new portal gate with double hooded locks and install air door, at or near the terminus of the <br />structural supports <br />13. install new track from terminus of the structural supports to the equipment storage building (see <br />Section 4.0 for storage building specs) <br />14. construct a narrow, —100 foot long snow shed to cover the track exposed on the surface that <br />begins at the terminus of the structural supports and ends at the equipment storage building (as <br />shown in Figure 2). <br />CBCI owns the surface of all of the lands for several hundred feet in every direction from the portal area; <br />however the location of the collapsed portal (Photo 1 and Figure 2) is very close to the 112 permit <br />boundary. It is likely that steps 1 -5, 8, 9, and 11 will partially occur approximately 50 feet outside of the <br />southern boundary. Once the backfill above the structural supports is completed (i.e. step 9), CBCI will <br />immediately reclaim the temporary disturbance caused by the excavation and backfill, as described in <br />steps 10 and 11. As per the July 19, 2012 site visit with CBCI (Mike Thompson and Bob Larson) and <br />DRMS (Bob Oswald and Russ Means), so long as CBCI immediately reclaims the temporarily disturbed <br />area above the collapse, DRMS stated that an amendment would not be required prior to approval of the <br />activity. <br />Technical Revision, Camp Bird Mine 112 Permit (Permit No. M- 1982 -090) Page 8 <br />