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(Page 2) MINE ID # OR PROSPECTING ID # M-1984-026 INSPECTION DATE 4/15/04 OBSERVATIONS INSPECTOR'S INITIALS RCO This inspection was performed bythe Division as part of its monitoring of Construction Materials 112c permits, and to perform a pre-operation inspection of a 36-acre area that is proposed to be added to the permit area (under Amendment AM-01). The operator was contacted to schedule a time for the inspection. The operator's representative named on page one was present during the inspection. The required permit ID sign was observed posted at the entrance gate, though, as noted in the Feb 2002 inspection report, the sign also contains an "extra" permit number: that of Pit #2, which was formerly a separate permit, but was included in this one when Conversion CN-01 was approved in 1998. The operator should revise the sign to reflect only the permit number of this active permit. Before revising the sign, please refer to Rule 3.1.12 for a description of the minimum requirements of the sign. EXISTING PERMITTED AREA The existing permitted area still consists of two separate pits, with an unmined area between containing several stockpiles of gravel and topsoil, a truck scale and the old CDOH steel bridge pieces. Most of the pit slopes of both pits are adequately graded, though topsoil replacement is not complete. The existing pits are approved for rangeland, and topsoil is required on the slopes and floor, as well as revegetation also. There are several topsoil piles located along the shoulder of the pit slopes. The west pit contains a small crusher, generator and loader, and a large amount of stockpiled gravel. The equipment was inactive at the time of the inspection. A diesel fuel tank was located in the floor near the crusher. The tank was empty, but had no impermeable secondary containment under it. The operator must not store fuel in an unlined facility, especially in a location so close to groundwater. The presence of the tank is not a problem, but it must be given appropriate secondary containment before filling, or removed. Salt sand was mixed for CDOT in the west pit during the winter, and a salty crust remains on several hundred square feet of the floor. This should be scraped up as much as possible, to reduce the potential for introducing salt to the groundwater. It may be spread onsite in areas such as roads, which will not be mined or will not be vegetated. The walls of the east pit are also well sloped, and mostly topsoiled. The north wall lacks topsoil. A good amount of volunteer grassy vegetation exists on the pit floor, mainly due to the proximity of groundwater moisture, because the floor has not been topsoiled yet. There is very little debris at the site. No noxious weeds were noted. AMENDMENT AREA The Notice that is required to be posted was observed at the entrance to the permit area. The proposed plan under this amendment application is to continue mining the existing pits to join them into one pit, then expand the pit into the amended area, toward the east. The northerlywall of the new portion of the pit will be maintained at an adequate setback distance from the Rio Grande Canal Lateral #1. Overhead high tension electric lines cross a portion of the existing permit area and the amended area. The operator must maintain an adequate setback distance from the poles also. The pit will be used as a recharge pit under agreement with the Rio Grande Canal, and will be seasonallyfilledtyhen irrigation water is introduced from Lateral #1 into the pit through a surtace ditch at the NW corner of the existing permit. The operator should ensure that concentrated flows from the ditch and across the pit slope do not erode or degrade the slope. Riprap, possibly grouted, or a piped conveyance down to the floor may be needed. A secondary ditch exists parallel to and on the south side of the larger Lateral #1, in the vicinity of the NE corner of the amended area. The secondary ditch is not shown on the amendment maps, and the lack of corner markers to delineate the proposed area made ft difficult to verify whether the secondary ditch was actually on the affected area or on the adjacent property parcel. The question of where this feature is in relation to the affected land is important, due to the setback distance to be maintained between the pit and the canal. (Note: upon approval of the amendment all permit boundaries or corners must be adequately marked.)