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I. EXECUTIVE SUMMARY CAMAS Colorado [nc.'s Aggregate Division (CAMAS). Lakewood, Colorado, is submitting the following document in order to apply for an amendment to its Division of Minerals and Geology (DMG) Permit No. 73- 21 which grants approval for mining operations at the Morrison Quarry in Jefferson County, Colorado. The proposed amendment would permit CAMAS to: 1. Expand [he limits of mining and limits of disturbance in the South Quarry; 2. Include a large engineered fill slope in the North Quarry to provide a new mechanism for visual impact mitigation for original quarry highwalls there; 3. Revise bench and highwall configurations for the existing North and Central Quarries and the formerly proposed South Quarry to accommodate the proposed South Quarry expansion and North Quarry fill slope; and 4. Allow mining [o bottom elevations different than previously proposed. The total additional disturbed land will be approximately 34.3 acres and the new disturbed land total will then be approximately_ 17~cres The amendment will allow mining to bottom elevations of EI 5,770 ft in the North Quarry (unchanged), EI 6,360 ft in the Central Quarry (unchanged), and 5,840 ft in [he South Quarry (new). The base map for the quarry used in this Amendment application is based on aerial photography which was digitized to generate a topographic map. Mapping based on 30 April 1998 aerial photography showing recent development of [he North and Central Quarries was spliced together with mapping based on 28 April 1993 aerial photography of presently unmined areas resulting in an accurate topographic map of the entire quarry showing existing conditions. The existing topography of the area is shown on Figure C-2, Exhibit C - Premining Plan. This figure shows the April 1993/April 1998 topography and depicts the results of mining and reclamation activities to date under the current permit and amendments. This map was used as the base map for the preparation of this mining and reclamation plan amendment and is the basis for conducting additional geotechnical evaluations of quarry slope stability within existing and future mined areas. Surface features such as drainages, roads and buildings are shown on the map of current conditions (i.e. "pre- mising" conditions with respect to this amendment) at the quany. A power line is shown at the southern limits of the proposed affected land which is owned by Mountain States Telephone and Telegraph Company as part of a right-of-way. Prior to possible mining within 200 ft of [he power line, CAMAS intends to initiate appropriate notification of the utility owner and institute required relocation of the line, maintenance of safe distance separation and/or engineering controls to ensure safe mining operations in that area. Surface drainage G:~PROlECf530-'OOOOTTFJ(T+AA1FNDp5.T%T 1 - t