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ORIGINAL -PUBLIC FILE (Page 2) MINE ID # OR PROSPECTING ID #: M-LqB.~-nRg INSPECTION DATE: I I~]8/nd INSPECTOROS INITIALS: ~_ OBSERVATIONS The Division conducted a monitoring inspection of the site as part of sites to be inspected during the fiscal years 2004- 2005. The site is a large 112 sand and gravel operation located in Douglas county approximately 6 miles South East of Castle Rock, Colorado. The total permitted acreage is 66.50 of which 57.5 acres could be affected. When the site was last inspected in 2001 operator was sited with two possible problems to the permit.l) The affected acreage was different from what was reported in the annual report. 2) Mining plan was for dry mining but water was noted exposed in the pit area and instead of the one approved detention basin, two were noted. Operator also had in place a well and pump generator which was being utilized for the portable wash plant. Operator was requested to submit a Technical revision to add the above items. On 7/11/2001 the technical revision to add the items was approved and the warranty was increased to $98,189.00. Present during the inspection on 11/17 and 11/22 was Mr. John Miner the operator. During the inspection on 11/17, the pit area which extends from the west to the East was observed to have water exposed Operator was notified to start backfilling immediately. Operator agreed to complet the backfilling all the exposed water no later than Monday the 11/22.That being the case, the fact that water is being exposed during mining will not be sited as a possible ""PB". Mine was active, at the time of the inspection depth of pit ranged approximately from 20 feet to 30 feet with pit width of approximately 100 feet and length of about 2000 feet. The Board approved depth of mining is 25 to 30 feet. Given the location of the operation along East Plume Creek there is a very high possibility that ground water will be exposed even at shallower depths that the Board approved limit. Operator has a well augmentation plan for 25 acre feet of water, however, operator has to make sure that the pit floor is dry at the end of each mining day. When ground water is exposed it has to be backfilled. The operator can submit a Technical Revision to change the mining plan from dry to wet, as long as there is an adequate water substitute supply plan for the pit area to be exposed. This way, until the mining is completed the operator will avoid to backfill the exposed ground water. On 7/22/04, operator was backfilling the pit so no ground water was exposed. Mr. Miner also mentioned the fact that the permit area was accepting fill material from outside source with the approval of the county and that all the fill material is inert, from construction sites and is being used to backfill and grade the mined areas. However, since there is no mention of accepting inert fill material in the approved permit, the Division will need how much fill material is being accepted each year. If the material accepted is not graded, as it is being placed, the Division will adjust the warranty accordingly. The operator will also need to submit a new mining and reclamation plan map for the site. In the mining plan maps please include the total affected areas for the operation.