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~ t • <br />Evaluation <br />All buildings at the mine site and the loadout have been dismantled and <br />removed. A perimeter fence surrounds the two properties and will remain as a <br />permanent structure, The shop building pad, the gravel yard, the domestic <br />well, and the septic system at the mine site were left at the landowner's <br />written request. The county has assumed jurisdiction over the tram road to <br />access the site. <br />Backfilling of the mine site and grading of the outslopes were conducted in <br />accordance with the originally approved plan. Observations suggest that the <br />back filled and graded areas are in a stable configuration. Same low wall <br />cracks have developed at the mine site. Approximate original contour appeared <br />to be achieved at both the mine and loadout sites. The operator submitted an <br />"as-constructed" map entitled "Actual Final Contours" in the bond release <br />package which matched reasonably well with the proposed post-mining topography <br />map. A ridge, centered at N4500 and E4000, was unplanned but does not <br />visually disrupt the topography. The ridge was built in 1984 with <br />construction of the East Dump and it appears that a slight deficit of material <br />resulted in a small swale to the north. <br />Terrace benches were installed as a water treatment facility at the mine site <br />under Rule 4.05.2(1). Field observations during the bond release inspection <br />indicated that the twelve terraces were installed, as designed, as ten foot <br />wide benches with 2%-4% inslopes. The terraces were not installed along the <br />contour, however, and slopes of 1% to 5% were noted on the certified terrace <br />profiles. Possible knickpoints were examined during the inspection and no <br />erosion was seen below the terraces or along the profiles. There appeared to <br />be an accumulation of mulch at some of these low points but the designed <br />inslopes appeared to have withstood the winter. The Division should retain <br />bond to re-install terraces along the contour should the need arise following <br />a significant precipitation event. <br />The 2.82 acre Northgate loadout had a small area exemption and no sediment <br />control structures during operation. Regrading, topsoiling and seeding of the <br />site occurred in 1988. The site has an elevation gain of less than two feet <br />and all precipitation at the site will remain on site. <br />Reclamation work remaining to be done is as follows: <br />A. Re-installation of the contour terrace bench system, if needed. <br />8. Removal of the cu]vert beneath the access road on the west edge of <br />the property updip from the shop area. <br />C. Removal of two temporary ditches. <br />D. Sealing and reclamation of two monitoring wells. <br />E. Measures necessary to achieve vegetative success. This may include <br />additional soil preparation, seeding, mulching and transplanting of <br />shrubs. <br />Cost estimates for conducting these activities are included in the following <br />section. At this time, the Division believes that the degree of difficulty to <br />complete these remaining reclamation activities to be low. <br />