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(Page 2) MINE ID # OR PROSPECTING ID #: M-~nnn-i ~ ~ INSPECTION DATE: n3/~pmF INSPECTOR=S INTfIALS: TAS 1. A site inspection was conducted of the Mamm Creek operation. Present during the operation were Mark Vigil and Mike Prehm of Lafarge North America. Digital photographs of the site were taken and are attached to this inspection report. 2. The mine plan for the Mamm Creek operation specifies excavation of alluvial sand & gravel from within the overbank area of the Colorado River. The operator has maintained a 100' buffer from the active, low Flow channel of the Colorado River as specified in the approved plan. The operator has also installed a flood control berm on the northern edge of the excavation areas to exclude the 50 year flood event during mining operations. The mine plan specifies excavation of four (4) cells at a depth of from 10-25 feet below ground surface. The site will be reclaimed to recreational use with 4 groundwater fed lakes. The operator has posted a financial warranty of $149,153 in the form of a corporate surety. The approved plan specifies that outlet spillways are to be installed in the beginning stages of excavation of each cell. During final reclamation, the operator will be installing an inlet spillway at the upstream end of each cell. During final reclamation, the existing flood control berm is to be removed and the berm materials backfilled into the pit excavation. 3. The operator has completed mining in the far east cell and has begun backfill and grading pit slopes to their final configuration. The operator has done a good job of contemporaneous reclamation, where possible. This inspector estimates the depth of excavation in this cell to be 5-7' below ground surface. The operator has installed the required flood control berm in the far east cell. This inspector estimated the berm height to be 2 feet above original ground level and a top width of 10'. The operator has also installed a riprapped outlet structure at the downstream end of the cell. The upstream, inlet structure has not yet been installed. 4. The operator has begun excavation in the far west cell with depth of excavation estimated to be 8 - SO' below original ground surface. Available topsoil had been salvaged and stockpiled for use in reclamation. At the time of inspection, this inspector could not confirm whether there was an outlet structure installed for this cell. The Division considers the matter of the spillway installation to be a problem that will require corrective actions. Please see page 4 of the report. 5. Review of the permit file indicates that inlet and outlet spillway designs for each of the four (4) reclaimed cells and a copy of the approved (final version) of the US Army Corps of Engineers 404 Permit has not been submitted and incorporated into the mining and reclamation permit as previously committed to by the operator. The Division considers this to be a problem that will require corrective actions. Please see Page 4 for corrective actions. 6. Review of the permit file indicates that there is no demonstration in the revised permit to address the potential for adverse offsite impacts during final reclamation when the existing flood control berm is removed and backfilled into the pit. In conformance with Rule 3.1.5(3) and Section 34-32.5-116(4)(1) of the Construction Materials Act, the operator must demonstrate that all grading during final reclamation shall be done in a manner to control erosion and siltation of the affected lands, to protect areas outside the affected land from slides and other damage, particularly during high Flow events when the affected land is expected to be subjected to stream flows at or above the ordinary high water mark, as defined by the US Army Corps of Engineers. The Division considers this matter to be a problem that will require corrective actions. Please see Page 4 for corrective actions.