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• (Page 21 • MINE ID # OR PROSPECTING ID # M-90-09A INSPECTION DATE 2/15/2000 OBSERVATIONS INSPECTOR'S INITIALS TAS 1. A site inspection was made of the Perry Pit located in Weld County, immediately east of Wattenberg along Weld County Rd.#6. The Perry Pit is also located west and within the 100- year floodplain of the South Platte River. Present during the inspection was James Krattenmaker of Asphalt Paving Company. The inspection was made as part of the Division's on-going 4-year inspection program. 2. The Perry Pit is permitted for a total of 118 acres. The operator has posted a financial warranty in the amount of $63,300. The mine plan specifies wet mining methods with three (3) phases of excavation. Excavation is expected to occur at a rate of 6 acres per year with contemporaneous reclamation of shoreline areas following immediately behind. The operator also maintains a 3 acre area ahead of the excavation, stripped of topsoil and overburden. The $63,300 reclamation cost is based on a maximum pit disturbance of 2,500 linear feet, and a maximum of 2H:1V slopes while excavation is taking place. The post-mining land use is pastureland with 3 lakes encompassing 57.7 acres of water surface. Shoreline slopes will be graded to a maximum of 3:1 from 5 feet above to 10 feet below the water surface, then 2:1 to the bottom of the lake(s). Topsoil will be reapplied to shoreline and surrounding pastureland at a depth of 6-12 inches. The lake shorelines will be revegetated with a grass mix as well as plantings of trees and shrubs. Surrounding pastureland areas will be revegetated with a grass mix. 3. The mining plan specifies a number of setback distances from significant, valuable, or permanent man-made structures. These include 1) a 50' setback from a gas well and accompanying facilities, 2) a 50' foot setback from the edge of the Lupton Bottoms Ditch, and 3) a 100' setback from the South Platte River. The operation was in compliance with these requirements at the time of inspection. The operator has done a good job of respecting these setback limits. (The operator has also committed to no excavation within 200' of the Lupton Bottoms Ditch until an agreement with the Ditch Company is secured). 4. Signs and markers were posted as required by Rule 3.1.12. The Perry Pit is currently active and all disturbances were evaluated and found to be within the permit area. Mr. Krattenmaker estimated the active pit disturbance (in the southern portion of the Phase 1 Area) to be 8-8.5 acres. This corresponds to approximately 2100 linear feet of pit working face, which is in r_ompliance with the mine plan. The excavation has exposed groundwater, therefore there is 8-B.5 acres of groundwater exposed to evaporative loss. Mr. Krattenmaker also estimated the acreage of plant site and stockpile area to be 15 acres. This inspector notes that the operator has done a good job of salvaging available topsoil for reclamation purposes and of backfilling the excavation with overburden as specified in the reclamation plan. 5. Fresh water (groundwater) is used in a closed wash circuit for processing of sand and gravel products. The process water is contained on-site in conformance with the mine plan. Mr. Krattenmaker indicated that Asphalt Paving Co. has an approved well permit and temporary substitute supply plan for these uses as well as evaporative loss from exposed groundwater. Mr. Krattenmaker also indicated that the operator/landowner is in the process of securing a permanent water augmentation plan for final reclamation. 6. The operator has committed to two (2) measures that will be taken to monitor and protect the flow of water in the Lupton Bottoms Ditch, which runs north-south through the permit area between the Phase 1 and Phase 2 areas. These measures include 1) installation of gauges in the main ditch channel to determine if there is any significant problem with water moving out