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use a backhoe or front end loader to knock down the overburden and load it into a haul truck than to <br /> try and scrape it successively off the surface. If scrapers were used that would be the way to do it,but <br /> having some scrapers that are only useful for that purpose is a great deal of overhead for something <br /> that is only done every few years. <br /> Thus the highwalls along the sides of the operation are as long as are needed to provide access <br /> for various purposes. Precise lengths cannot be provided because there are a lot of variables. And <br /> even though the gravel highwall extends from side to side, a large surface of gravel is initially exposed <br /> and this extends outward from the overburden cut for a few hundred feet, at the most,when a new <br /> area of mining is exposed. Naturally, as the mining proceeds this exposure of the gravel layer becomes <br /> narrower until the distance between the safety berm beside the road on the shelf and the gravel bench <br /> is maybe 20 feet wide. Then more stripping is done. The point is,this east-west wall can become <br /> curved to the south in the middle because mining of the inner part of the exposure proceeds a bit more <br /> rapidly than the edges. The edges tend to be the last part of the gravel seam to be trimmed off to return <br /> the gravel highwall to a more straight, east-west line. <br /> Maximum length of the main working face (east-west) can range from about f2,300'when <br /> straight to ±2,700'when curved. The length of the side highwalls are more difficult to determine <br /> because they essentially serve as roadways and can potentially run the full length of the operation or at <br /> least to a point where it is necessary for the road to come up to the surface elevation or drop down to <br /> the bottom of the pit. A nominal length of each would be 11,500'each or± 3,000'for both. So, a safe <br /> number to use for calculations would likely be±5,500 feet of TOTAL highwall length. <br /> However, this comes with a need to point out that the way the reclamation of these highwalls <br /> is implemented also affects the Reclamation Cost of this feature in the bonding. For discussion of that, <br /> please refer to the "Grading and Backfilling" section in the Revised Reclamation Plan. It is likely that <br /> these highwalls will not be backfilled by end dumping overburden over the edge of the highwall. But <br /> rather the highwalls will be eliminated by cut and fill techniques where the cutting off of the top <br /> provides much of the fill for the bottom so the result is a 3:1 slope without the sloped internal layers <br /> of end dumped material that encourages slumping of the slope if it becomes very wet or even <br /> saturated with water. Some fill may still be needed to round out the total volume of the slope,but that <br /> should not occur to a large extent. <br /> The overburden removed will also be used to cover the gravelly bottom of the pit with a more <br /> finely textured material for revegetation purposes. For a discussion of that, also refer to the Revised <br /> Reclamation Plan. <br /> Fountain Pit Technical Revision#3 - June 2022 M-1982-155 Mining Plan Page 21 of 22 <br />