2012-07-23_REVISION - M1977211 - Laserfiche WebLink

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76019- 0001/LEGAL23614308.1 July 23, 2012 Amendment 3, M -77 -211 / Notice of Violation MV- 2009 -012 Continental Materials Corporation, Transit Mix Aggregates, Castle Concrete Pikeview Quarry Technical Revision 15 — 6/7/10 Additional geotechnical investigations by Exponent Technical Revision 16 — 6/6/11 Additional geotechnical investigations by Exponent At this time, CMC /Castle/TMA has prepared a revised reclamation and mining plan to reclaim the site. The reclamation plan has been designed to achieve a stable configuration at the site using safe construction techniques, and to minimize further disturbance. The final configuration will be performed in a manner to control erosion and protect areas outside the affected land from slides. The proposed reclamation plan will create a landscape consisting of a sequence of altemating benches and highwalls on approximately 15 acres between 7480' and 7923', which will result in a 1:1 (horizontal:vertical (H:V)) slope. The maximum height of this disturbance is expected to be 443', but an average height is closer to 200'. The reclaimed slope below will range from 3.7:1 (H:V) to 3.9:1 (H:V), and will extend across 101 acres between 7480' and 6950'. Seegmiller International has performed a geotechnical evaluation of the proposed mine plan along three cross - sections, north, central and south which show a safety factors under dry, r saturated, and both of those cases with a of a seismic event. The analyses have been performed on the proposed benches as well as the sloped fill below. The submitted plan identifies the addition of two small parcels on the western perimeter totaling 4.5 acres. At this time 1 acre of the southern parcel is slated for disturbance, however, disturbance may expand further west, should actual geological conditions not be exactly as projected. However, CMC /Castle/TMA are taking the conservative approach to expand the permit area onto Forest Service land to minimize the potential for disruptions during reclamation. CMC / Castle/TMA are planning to file a Special Use Permit for the additional land as a Categorical Exclusion described by 36 CFR 220.6. On behalf of CMC / Castle/TMA, we respectfully request that this Amendment be approved with a stipulation to acquire the USFS Special Use permit prior to activities in the two parcels. The proposed revegetation plan is described in detail in the Amendment and it differs from previously permitted plans, given the slope configuration. In summary, evergreens will be planted on the benches to provide visual diversity when viewed from within the community and to expand wildlife habitat. A post- mining reclamation density of 30 trees per acre is proposed, given site conditions. Typically, there will be no revegetation on the slopes between the benches, due to steep and potentially unsafe working conditions. The gentler slopes below will be reclaimed with pinyon juniper with a reclamation objective of 21 to 43 trees per acre as the elevation rises. As described in the Amendment, reclaimed lands below 7250' will be revegetated with a Gambel's oak - mountain mahogany community. Plantings along waterways will be supplemented with deciduous species to diversify wildlife habitat.