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(Page 2) MINE ID # OR PROSPECTING ID # M-1979-097 INSPECTION DATE 01/13/04 INSPECTOR'S INITIALS ESC This was an inspection of the East Rigden Pit, File No. M-1979-097 conducted by Erica Crosby of the Colorado Division of Minerals & Geology. Eric Reckentine, John Rozelle and Kevin Moore of Lafarge were present during the inspection. The inspection specifically focused on the lateral berm that separates the East Rigden Pit from the adjacent Port o£ Entry (POE) Pit operated by Lafarge (Permit M-1962-182). During the Division's inspection of 3/13/02 it was noted that the La Poudre River breached the lateral berm that separates the pits during the flood of 1997-1998. Floodwaters entered the East Rigden Pit on the northeastern edge and continued into the POE Pit. Lafarge submitted a technical revision (TR-02) to address a weir that was constructed along the La Poudre River to direct floodwaters into the East Rigden Pit. The weir was designed and constructed to control the elevation of waters entering the East Rigden Site in order to protect the Rigden Bridge and the overhead conveyor that had been installed to convey material from the Resource Recovery Site on the north side of the river. The weir was required by the City of Ft. Collins in order to control river flows into the pit. TR- 02 was approved by the Division on April 2, 2003. However, TR-02 failed to address how floodwaters would exit the East Rigden Pit and enter the POE Pit. Under the Construction Material Rules and Regulations, areas outside of the affected land shall be protected from slides or damage occurring during the mining and reclamation operation [C.R.S. 34-32.5-116 (4)(i)]. The breached lateral berm is approximately 50-feet wide by 100-feet long. No repairs or improvements have been made to the berm since the 3-13-02 inspection. Because repairs to the lateral berm must encompass POE and East Rigden, a technical revision must be filed addressing the stability of the lateral berm within the East Rigden permit area. The revision should be submitted in conjunction with the Division's adequacy comments for the POE Pit (TR-O1), or no later than March 1, 2004. Please see the POE inspection report dated 1-13-04 for further detail. The Division observed that Lafarge installed a low-water crossing to access a parcel of land on the east side of the La Poudre River. The permitted area is defined as the Baumgartner property. The mining limits are 13.4 acres in size. The amendment application (approved in 1980), incorporates the general crossing area within the permit boundary area, but does not state that a crossing will be installed. Lafarge will need to submit a technical revision to the permit addressing the low-water crossing across the La Poudre River by March 1, 2004. Lafarge will need to address the following in the revision; 1. Specify how the low-river crossing will be constructed. In particular, state; • The amount of topsoil to be salvaged and the location of the topsoil pile. • Describe the associated drainage and runoff conveyance structures and include sufficient information to evaluate structure sizing. • Describe if any rock armoring will be used along the bottom of the Creek and provide the sizing and gradation of the material. • Describe how water will be managed during the construction period and use of the low-water crossing. • Describe measures to insure impacts to the water within the La Poudre River are mitigated. 2. Explain how the low-river crossing will be reclaimed. In particular, state; • The structures that will be removed from the creek (culverts, rock material, etc...) and where this material will be disposed. • The depth of topsoil to be replaced on affected areas. • The slope of the reclaimed banks. • Measures that will be taken to revegetate the site (when the site will be seeded and how the seedbed will be prepared to eliminate compacted conditions). • Describe the grass, forb, shrub and tree species to be planted and the applicable quantities and the application method.