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Page 2 of 2 MINE ID # OR M-1986-079 INSPECTION DATE: 9/28/06 INSPECTOR'S CMR PROSPECTING ID #: INITIALS: This site inspection was a result of a recent Technical Revision (TR) in which the Lafarge North America (Operator) requested to backfill an approximate 45 acre pond at the M & G mine site to two feet above the groundwater level. The Division of Mining, Reclamation and Safety (Division) denied this TR because backfilling the site was deemed a significant change to the reclamation permit and could not be covered under a TR. The Operator submitted a second TR (TR6) to move the location of a previously approved fill (TR4) of an 8.85 acre pond to a new location; an isolated portion of the pond on the north side of the permit area. The Operator notified the Division during this process that a majority of the mine site had filled with water, and that this exposed pond did not have any water rights associated with it. After a review of the permit file, it appears that this site has had exposed water for much of its history, without having an approved Substitute Water Supply Plan. According to the previous Operator, the pond dried up (except a remnant 8 acre pond) several years ago during construction of the slurry wall around the adjacent Dunes Pit. For unknown reasons the pit refilled with water in July of 2006. Based on visual observations and planimeter readings from available aerial photography of the site the total exposed water within the permit area is estimated to be 45.75 acres. This is broken up into two ponds separated by a berm/road. The larger pond is about 38.25 acres and the smaller approximately 7.5 acres. There is another approximate 5-acre pond that use to be in the permit area but was released. The majority of the larger pond is open water greater then 3 feet deep, except that on the southwest area where it is one to two feet deep and has extensive emergent vegetation (willows, cottonwoods and cattails). The smaller pond is deeper toward the center and shallower around the edge with willows and cottonwoods. The upland areas are graded and covered mostly in annual weeds. The post mine land use is listed as Wildlife. TR4 established the primary reclamation feature as an 83 acre lake. TR5 allowed for placement of fill to two feet or higher above the waterline for the remnant 8.3 acre pond that was onsite at the time. TR6 moved the 8.3 acre pond that was permitted to be filled to the isolated pond on the north end of the mine site. This results in an end reclamation of the site as mostly pond with some upland and filled areas. The Operator does not currently have a Substitute Water Supply Plan for the water in the pond, and as a consequence the presence of the pond will be listed as a problem (Rule 3.1.6). The Operator has stated that the proposed reclamation plan for the site is to backfill the lake. The Division considers that a significant change and would require the Operator to submit an amendment to adjust the reclamation plan and post mining land configuration. Please see the section below for required corrective actions. If the Operator chooses to fill the existing pond, there does not appear to be sufficient topsoil on site to ensure successful vegetation reclamation. The Operator will need to secure sufficient topsoil, or create a growth medium that will allow for successful vegetative reclamation (rule 3.1.9 and 3.1.10). The plan for the topsoil can be included in the permit amendment. There was not the required sign at the entrance to the mine (Rule 3.1.12). The Operator will need to put in Enforcement and Inspection Contact Address NAME: Steve Brown OPERATOR: Lafarge STREET: 10170 Church Ranch Way, Ste. 200 CITY/STATE/ZIP: Westminster, Colorado 80021 cc: U.S. Army Corps of Engineers CO Hazardous Materials and Waste Division U.S. Bureau of Land Management X_ CO State Engineers Office U.S. Forest Service CO Water Quality Control Division CO Department of Transportation OTHER: