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RULE 6.5--GEOTECIINICAL STABILITY EXHIBIT <br />Blasting <br />Conventional blasting technologies will be employed to fragment marble rock at this <br />location. All contractors on site will have valid blasting licenses for the transport, <br />storage, and use of explosives and will have written protocol for safe use and public <br />safety awareness at this location. There aze no valuable permanent man-made structures <br />other than CR 228 within one mile of the mine site. Use of explosives at this site is not <br />expected to have any significant negative impact on structures or the surrounding lands. <br />The execution of proper protocol for worker and public safety will insure that blasting <br />operations have no impact on the safety and well-being of site workers or public. <br />Highwall Considerations <br />It is generally appazent from the condition of the existing highwall rock face that the <br />primary joint pattern (strike N15E, dip 77°E) of the white marble bed allows for at least <br />short term control of the highwall face. This aspect can be viewed at a more or less <br />smooth rock face contact which supports the highwall face for as much as 90 feet in some <br />locations within the current pit azea. However, secondary and tertiary jointing systems <br />that can be seen at a number of locations within the pit appear to control internal <br />fragmentation of the mazble body and may limit long range stability. The secondary and <br />tertiary jointing systems range from a strike of N67E to N90E and dips range from 48°S <br />to 76°N. The secondary and tertiary jointing systems observed in the white marble do <br />not support evidence for long term competency of the mazble bed for use as permanent <br />highwall contact. For this reason as well as the limited volume of resource at this <br />location. The white mazble bed will not used as a final highwall contact in the permanent <br />highwall bench system. The lower benches as projected in the highwall bench system <br />will be backfilled with waste rock as mining proceeds to the northern end of the deposit. <br />In the final stages of reclamation, waste rock from the north end rockpile azea will be <br />bulldozed back into the final production cut after completion of mining. <br />The black, altered quartzite bedrock which occurs west of the white marble bed will be <br />primary bedrock exposed along the highwall contact after completion of mining. There is <br />not much direct physical outcrop available at the surface above the white mazble cut at <br />the present time, which limits assessment of the rock types capability for highwall <br />competency. Soils currently at the surface above the mazble contact aze relatively thick <br />with good vegetative cover. The few abandoned mine pits show primarily an altered <br />metamorphic rock formerly sandstone and siltstone textures, with mafic dykes and sills of <br />iron and manganese rich igneous intrusive components. The bedrock outcrop available <br />for inspection at the surface in the line of strike of the metasediments lying west of the <br />mazble bed but south of the main mazble cut (southwest comer of affected land) show a <br />hazd to very hard quartzite rock type that would have good qualities regazding highwall <br />bench development. For this reason, it is planned to perform a more detailed <br />geotechnical evaluation of the meta-sediment once bench development has proceeded at <br />36 <br />