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(Page 2) • MINE ID # OR PROSPECTING ID # M-94-093 INSPECTION DATE 10/24/00 • INSPECTOR'S INITIALS ESC This was an inspection of the Dahlia North Resources Pit conducted by Erica Crosby of the Division of Minerals & Geology. Jamie Gaboriau of CAMAS Colorado, Inc. and Tom Terry of GEI Consultants, Inc. were present during the inspection. The inspection was in response to a citizen complaint letter from Frances McLaughlin, an adjacent landowner. The Division spoke with Ms. McLaughlin on October 17, 2000 and October 20, 2000 regarding impacts to her well from recent dewatering activities at the Dahlia North Resources Pit. Ms. McLaughlin followed up with a citizen complaint letter on October 23, 2000. The main concern is regarding activities at the site which include installation of a pipeline between the Dahlia North Resources Pit and the adjacent Flanagan Dahlia Pit, Permit No. M-86-066. The letter states that aggressive dewatering of the pond to the west of her property resulted in the water level in the pond east of her property to also drop. Ms. McLaughlin is concerned that draining the water from the pond could affect the water well, which is 30 feet in depth. CAMAS filed for an Application for a Permit Amendment (land swap) on September 29, 2000. The Amendment proposes to add a one-acre portion of the East 88`" Avenue right-of-way to the permit area to facilitate installation of a pipeline that will connect the Dahlia North Pit located north of 88`" Avenue to the Flanagan Dahlia Pit (Permit No. M-89-066) located south of 88`" Avenue. Both pits are surrounded by slurry walls and will be operated as water storage reservoirs by the City of Thornton. According to the application, a portion of the pipeline is to be installed under "Area 1" which is depicted as a 5-acre groundwater pond. The pond was wet mined by CAMAS, and not included in the slurry wall area. The Division inspected "Area 1" of the Dahlia North Resources Pit and noted a water pump and pump hoses in the pond. This pond is located to the west of the McLaughlin property. No pumping was taking place during the inspection. According to Tom Terry, pumping activity stopped on October 20, 2000. The exposed water level appeared to be five feet lower as a result of the pumping activity. According to Mr. Terry, the water level in the pond has raised approximately one foot since pumping ceased. The two small ponds to the east of the McLauglin property is under 110 Mining Permit No. M-99-090 and is referred to as the Teti Mine. This 9.9-acre property was also wet mined by CAMAS. Ms. McLaughlin observed the water level in these two ponds to drop during the dewatering activity. The Division met with Ms. McLaughlin to discuss the dewatering activity and the potential impacts to her well. The Division concurs that dewatering the Area 1" pond west of the McLaughlin property may have an adverse impact on her well and water rights. Mining areas located outside of the slurry wall were specifically mined wet to ensure that there were no impacts to the surrounding well owners. The operator must cease all dewatering activity until it can be demonstrated that such activity will be managed to protect against injury to existing water rights. Such demonstration will need to be filed with the Permit Amendment 002. In addition to the dewatering of the "Area 1" pond, roadwork was actively taking place on 88`" Avenue in the location of the slurry wall pipeline area. The operator should be reminded that the work associated with Amendment 002 may not proceed until the Division approves the Amendment and the appropriate financial warranty is posted.