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<br />5-02. OVERBURDEN/TOPSOIL PLACEMENT <br />Topsoil, per se, is no[ abundant on [his permit site. As has been previously described in prior amendments <br />(under Exhibit [ -Soils Information), soil units as mapped by the Soil Conservation Service (SCS), are the <br />Ratake-Cathedral complex and rock outcrops. Soils are formed in-place from parent bedrock and usually do <br />not extend deeper than 18 to 20 inches and consists of a stony, sandy loam which is very low in organic <br />content. Topsoil is often as thin as 6 to 12 inches and bedrock crops out on ridges. However, portions of the <br />quarry, particularly in Unnamed Drainage No. 1 and near the east end of the North Quarry expansion, deeper <br />overburden up to 40-ft thick and consisting of soil and weathered rock is anticipated. <br />As has been practiced at the Morrison Quarry for many years, overburden removal occurs in the months of <br />December or January to clear an area to bedrock in preparation for the mining "season" (February through <br />November). Overburden consists of the above-mentioned soil complex and regoli[h (weathered rock strata) <br />to the depth of competent bedrock which can be efficiently mined and processed. If benches are available for <br />reclamation (i.e., completely mined to the specified mining plan), overburden is placed on the bench and <br />shaped and graded in preparation for topsoiling and hydroseeding. If no benches are available for backfilling, <br />overburden is placed in temporary stockpiles. <br />In Amendment No. 4, CAMAS provided estimates of existing overburden stockpile reserves, overburden <br />expected in Unnamed Drainage No. I, and proposed overburden stockpile area capacity. At that time it was <br />estimated that approximately two times the material needed for reclamation of the Central Quarry was available <br />when needed when Central Quarry mining was complete. These conditions have not changed with this <br />Amendment. <br />The new mining and reclamation plans include the engineered fill slope in the North Quarry and additional <br />flat highwall and bench configurations proposed for "top-to-bottom" backfill for visual impact mitigation. This <br />proposal exceeds the minimum reclamation requirements of the DMG, but is desirable as part of the <br />cooperative effort between CAMAS and the Town of Morrison. Therefore, calculations have not been made <br />to "prove" that anticipated overburden quantities will meet reclamation backfill requirements shown in this <br />Amendment. Rather, CAMAS is committed to meeting proposed visual impact reclamation using available <br />overburden and finer-grained saleable product such as structural fill and/or granite sand as necessary to meet <br />visual impact mitigation commitments to the Town of Morrison. <br />Topsoil will be segregated from overburden where it exists for final "topsoiling" of backfilled slopes. <br />Experience in the Central Quarry has demonstrated viable reclamation using overburden backfill and available <br />topsoil to support healthy native grasses, shrubs, and trees. <br />Overburden stockpiles will be seeded in the early spring of each year if disturbance during [he winter (addition <br />or removal of material) has occurred. The stockpiles will be seeded with a mixture of smooth brome and <br />c:waorecrs~ozovaon,fxTwn~xoas.rx r V - 2 <br />