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(Page 3) MINE ID # OR PROSPECTING ID # M-2000-034 INSPECTION DATE 02/03/05 INSPECTOR'S INITIALS ESC No active mining was taking place during the inspection. A concrete plant is located within the Flatiron pit area and appears to be an active. The Flatiron pit was historically mined, and a number of ponds and piles remain. No substantial mining has taken place in the pit as proposed by Lafarge in phases 2 and 3. The pit area will ultimately be reclaimed to an open- water, unlined reservoir or lowland wildlife habitat. A pipe will eventually be installed between the Flatiron pit and the adjacent reservoir for filling and maintaining water in the reservoir. Mining in the Phase 1 Reichert Pit was completed in 2003. According to the approved permit, the area is to be reclaimed as lowland grass and shrubs. Pit slopes are to be backfilled to 3h:ly with native material, and 12" of topsoil is to be place on the side slopes of the pit. A small groundwater pond was noted, and it appeared that the pit was actively being dewatered. It was noted during the inspection that concrete and fill dirt from off site has been placed in the Reichert Pit. Wet concrete was observed being disposed of in the pit, in a non-cured state. The operator did not include the disposal of inert material in the original permit application or as a notice under Rule 3.1.5(9). Inert materials are defined in regulation, Code of Colorado Regulations (CCR) 6-1007-2, as "...non-water-soluble and nonputrescible solids together with such minor amounts and types of other materials as will not significantly affect the inert nature of such solids according to the rules and regulations of the board. The term includes, but is not limited to, earth, sand, gravel, rock, concrete which has been in a hardened state for at least sixty days, masonry, asphalt paving fragments, and other inert solids including those the board of health may identify by regulation." In addition, biodegradable materials such as wood and wood products is not considered an inert material. The operator will be required to address the requirements of Rule 3.1.5(9) as to the disposal of concrete within the approved permit area. In addition, because the non-cured concrete is in contact with water in the pit, the operator will need to demonstrate that groundwater has not been impacted by such activity. The operator will need to submit the following in regarding backfilling using inert material, the following information must be submitted by May 2, 2005; • Address the requirements of Rule 3.1.5(9) for all fill generated outside of the permit area to be used in reclamation of the pits. • Clarify how the operator verifies on site that material is clean and inert, and that wood and wood products are not backfilled into the pit. • Lafarge will need to ensure that any concrete disposed in the pit/pond must be in a hardened state for at least sixty days. Please describe the handling and dumping procedures to ensure this requirement is met. • Verify to the Division that the surface water and groundwater have not been impacted or polluted as a result of the non-cured concrete placed in the pit/pond. The operator will need to collect a water sample from the Reichert Pit, one up-stream and one downstream streamside water sample in the Big Thompson River, and one groundwater sample (either in a new or existing well). The parameters to be monitored shall include pH, dissolved Aluminum (A1) and dissolved Selenium (Se). If a high ph or Se is detected, then further monitoring may be required. 2 & S Contact Address j' CE NAME Eric Reckentine j' BL OPERATOR Lafarge West, Inc. j' FS STREET 10170 Church Ranch Way, Suite 200 j' HW CITY/STATE/ZIP Westminster, Colorado 80021 j' HMWMD (CH) j' SE Cc: Carl Mourit; DMG j' WQCD (CH)