2009-05-26_REVISION - M1993041 (3)

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The total affected land for the life of the mine is 464.9 acres. This information is depicted on Figure 3: Total Affected Land - Life of Mine. • Update and Clarify Current Approved Mining Plan The current mining plan is essentially the same as that approved in the 1994 Permit Amendment. Figure 3 shows the ultimate mine pit perimeter and that boundary has not changed. Figure 3 also shows the location of the 20-acre wetland to be constructed at final reclamation. Within the mine pit perimeter sedimentary rocks containing limestone and shale will be mined, this includes what is referred to in the permit as the Hi-Cal Ridge, and the 2nd 3rd, and 4th Ridges as well as some interidge material. Figure 4 is a typical cross section of these rock units showing the mining configuration. Cemex is requesting approval, through this Technical Revision, of a change in the sequence of backfilling from that sequence currently presented in the 1994 Permit Amendment. At the southern end of the mining area there is a seeded waste rock stockpile (this is labeled on Figure 3). The current permit calls for this material to be used as backfill at the northern end of the mine near the time of final reclamation. It would be more efficient to use the waste rock material for reclamation backfill now because the haul distance would be greatly reduced. Cemex would leave enough material along the County Road to achieve the berming and screening function, but excavate the remaining material for use as on-going backfill in the active mining area. • Maximum Depth of Mining The maximum depth of mining is 170 feet and this is in the Hi-Cal Ridge. The maximum depth of mining in the other ridges is 80 feet. • Demolition of Structures There are four structures in the permit area that may be subject to demolition after mining is completed and therefore are subject to financial warranty to cover the cost of the demolition. The four structures are: the crusher building and retaining wall adjacent to it, a maintenance building and two trailers (office / breakroom). The dimensions and building materials of each of these structures are as follows: Cemex, Inc. - Dowe Flats Limestone Mine Page 3 2009 TR-02