2013-11-06_INSPECTION - M2005080

Home Browse Search

PERMIT #: M- 2005 -080 INSPECTOR'S INITIALS: MAC INSPECTION DATE: October 23, 2013 OBSERVATIONS The inspection was conducted by Michael Cunningham of the Division of Reclamation, Mining and Safety (Division). Jack Allen of Allen Drilling and Excavating was also present for the inspection. The Allen Pit is located approximately 2.5 miles southeast of Fairplay, Colorado. The site is permitted for 59.5 acres, with a maximum allowed disturbance of 15.8 acres. The commodity of interest is sand and gravel and the post - mining land use is rangeland. The permit sign was posted at the site entrance and the boundary of the affected area was clearly delineated as required by Rule 3.1.12. Active mining operations were not occurring at the time of the inspection. The Operator routinely removes material from the product stockpiles to be used in the concrete batch plant which is located on the western perimeter of the site. The site is being mined in five phases; mining is currently taking place in Phase 2. The material is screened and washed using portable equipment located in the northern portion of Phase 1 and Phase 2. The wash water is piped to a series of settling ponds which are located on the east side of the access road. When the water reaches the lowest of the settling ponds, the water is pumped back to the processing area and is recycled in the wash plant. The Division observed numerous product stockpiles around the process area. Overall, the site was in a neat and orderly condition; the Operator has done an excellent job to minimize disturbance at the site. Hydrologic Balance: The Division observed standing water on the pit floor along the perimeter between Phase 1 and Phase 2. The water was located in a trench with approximate dimensions of 15' w x 100' 1 x 1'd. According to Mr. Allen, the trench was excavated to route water away from the southern portion of Phase 1 and 2 in order to bring the pit floor to final grade and to complete final grading of the pit walls. The top of the trench was approximately 12- 14 feet below the elevation of the surrounding area. Based on these observations the Division concluded that the water in the trench was groundwater and not surface runoff. The approved Reclamation Permit clearly states that groundwater will not be exposed at the site. The Reclamation Permit was approved with the stipulation that the Operator maintain a two foot buffer between the lowest depth of mining and the highest groundwater surface at any time during the year. The exposure of groundwater at the site has been cited as a problem and will require corrective action by the Operator; please see the first page of this report for additional information. There is a sufficient amount of material, including wash fines and overburden, available to backfill the trench to eliminate any exposed groundwater. The Operator indicated that an augmentation plan had been obtained from the Office of the State Engineer (SEO) which would allow for the exposure of groundwater. A review of the permit file showed that the Division does not have a copy of the Operator's augmentation plan. If the Operator does have approval through the SEO, a Technical Revision must still be submitted and approved by the Division to modify the Mining Plan to allow for exposed groundwater. Any future exposure of groundwater without the necessary approvals may result in enforcement actions. The Operator has two wells on the property; one well is used to supply water to wash plant and the other well is used to supply water to the concrete batch plant. The Division has copies of well permits on file for the monitoring wells which were used to monitor groundwater levels prior to the commencement of mining. However, the Division does not have any documentation which demonstrates that the monitoring wells were converted by permit for an alternate use. The lack of documentation for the two wells has been cited as a problem and will require corrective action by the Operator; please see the first page of this report for additional information. Page 2 of 5