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MINE ID # OR PROSPECTING ID # M-1977-205 INSPECTION DATE 2-14-2002 (Page 2) OBSER-- INSPECTOR'S INITIALS SSS This was a routine monitoring inspection conducted as part of the DMG ongoing monitoring program for active mine sites in Colorado. This was the first inspection following approval of Amendment No. 1 which added phases 1-5 to the permit area. The instream portions of this permit are not going to be mined until significant gravel recharge has occurred in the stream bed and grade control structures have been constructed. The past several years have had poor spring runoff and poor gravel recharge. The current snow pack seems to indicate that gravel recharge will be minimal again this spring. Phase 1 is currently being mined and is approximately half mined out. Excavation is proceeding east to west as approved and has a current estimated depth of 20-25 feet to shale the pit Boor. Slopes behind the active mining face have been sloped to 3H:1 V or less. Tri-County has not excavated into vegetated areas where wetlands were identified. However, since shutting off irrigation to the fields immediately east and south of Phase 1, Tri-County indicates that the wetland area has dried up. They indicate that they will request a re-inspection of those areas by the Corps of Engineers and mine them if the Corps indicates that the hydrology component of wetlands does not exist there. This is already an approved component of the DMG permit and would not require any revisions of the DMG permit to mine the portions determined not to be wetlands. The permit indicates that no dewatering will occur. However, the operator indicated that they did pump down phase 1 of the pit and mine it with front end loaders. They also indicated that they would like to continue mining in this manner. In order to do this, a technical revision will need to be submitted to address this revised mining method, any impacts to surface and groundwater hydrologic balance, and provisions for maintaining vegetation on the areas designated as riparian buffer zones. The operator must secure DMG approval of this revision prior to re-initiating dewatering of the pit. DMG does have a copy on file of a discharge permit for pumping to the river from a settling basin. With the approval of Amendment No. 1, Tri-County committed to submitting baseline cross-sections and longitudinal profile of the river channel prior to high water in the spring of 2000. Review of the file indicates that these baselines have not been submitted. This is listed as a problem on the last page of this report. Tri-County gravel must submit these baseline river channel surveys prior to March 31, 2002. Grand Junction Pipe has an asphalt batch plant setup on the west end of Phase 2. These facilities appear clean and orderly with proper spill containment where necessary. The plant is constructed of portable components. The crusher is located between Phase 1 and 2 as specified in the approved permit. Topsoil is stockpiled on the west end of Phase 2 in the buffer area just north of the asphalt plant access. This location is not exactly where the maps indicate the stockpile would be located, but the current pile location does not pose a problem. Tri-County Gravel will need to be careful not to partially bury trees with the stockpiled topsoil. This can cause tree mortality which is not desirable in the wildlife buffer area. Tri-County has been mechanically removing some Tamarisk and Russian olive, which they indicated are now on Delta County's noxious weed list. The stumps of the removed trees seen to sprout more stems than were originally removed creating a thicker, more vigorous stand. Tri-County will need to apply an appropriate herbicide to the stumps in the future to prevent regrowth. The NRCS or a local nursery should be able to specify an appropriate herbicide and application methodology. The reclamation cost estimate was not recalculated as part of this inspection. The current estimate was recalculated less than three years ago and the operation is in compliance with the approved mine plan and reclamation plan, Therefore, the current financial warranty is believed to be adequate to reclaim the site per the approved reclamation plan. Responses to this inspection report should be directed to Steve Shuey at the Division of Minerals and Geology, Grand Junction Field Office, 101 South 3rd Street, Room 301, Grand Junction, Colorado 81501, phone number 970-243-6368. I & onta + nr+dr cc cc: NAME OPERATOR STREET CITY/STATE/ZIP Tom irr Tri-County rav r P. O Box 66 Hotchkicc r•olor^do 81414 ^ CE -Grand Junction Office ^ BL ^ FS ^ HW ^ HMWMD (CH) ^ SE ^ WOCD (CH) ^ OTHER