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area horizontally in Area H, and depth of mining was not to exceed 30, feet with maximum <br />cut slope angle of 48 degrees. In 2001 the operator submitted a Technical Revision to the <br />permit requesting to deepen the excavation of the bottom lift in the South Pit from the <br />approved 30 feet to 70 feet and change the cut slope angles from 48 degrees to 53 degrees. <br />This Technical Revision did not, however, change the maximum area to be exposed which was <br />remained at 25% maximum at any given time horizontally. The Division believes the maximum <br />horizontal area of the pit exposed, where the operator was conducting active mining <br />operations at the time of the slide, was in excess of 25%. In addition, in the enhanced <br />reclamation plan the operator stated that "Since Castle Concrete began mining the site <br />three major slippages have occurred. Two of them occurred in the mid 1970's and the last <br />one below peak 3 occurred in January 1993. All the three slippages occurred because the <br />clay zone became soaked with seepage water. In all three cases, the volume of rock that <br />slid is best measured in hundreds of thousands of tons". However, Castle Concrete's plan <br />states that the area will be mined safely, even under these conditions. In addition, <br />Castle Concrete was also aware of major geological hazards on site when they submitted and <br />got an approval from the Division to safely mine the limestone and reclaim the site as <br />approved in the enhanced reclamation plan in 1994 and 2001. <br />As a result, DRMS believes Castle Concrete was in possible Violation of C.R.S. 34-32.5- <br />116(4)(i) and (4)(q)(I), and 34-32.5-124(1) along with Rule 3.1.5(2),(3)&(4) for failure <br />to protect areas outside of the affected area from slides or damage occurring during <br />mining or reclamation operations, failure to concurrently reclaim by not properly <br />backfilling the mined out highwall in Area H, and failure to comply with the conditions <br />of the permit by exposing greater than 25% of the highwall at any one time. <br />In addition, when Amendment # 2 was approved by the Division for the Lay Back area in <br />2001, the Division placed the following condition to the amendment approval. <br />No portion of the quarry high wall will be constructed (mined) to slope angles steeper <br />than the granite east joint dip without prior approval by the Division. Castle Concrete <br />will report to the Division, as soon as the granite is exposed, the east joint dip and the <br />bench high wall slope angle for each cliff (bench high wall) at approximately the north <br />and central ridge location. Castle Concrete will report the dip and slope angle at these <br />two locations for each new bench high wall until the final granite portion of the high <br />wall configuration is completed. The report will be prepared and signed by a registered <br />geotechnical engineer or other qualified engineer, and include an analysis of the <br />stability of the cliff (bench high wall) as it relates to the overall stability of the <br />amendment area quarry high wall. If such analysis reveals potential stability problems, <br />Castle Concrete will propose a modification to the mining plan to eliminate the <br />instability <br />problem. <br />Since the operator failed to provide the report upon exposure of the granite but continued <br />to mine in this area, the Division believes this is a possible violation of CRS 34-32.5- <br />124(1) and the approved reclamation amendment to the permit for failing to provide the <br />report once the granite was exposed. <br />In addition, this report includes several Corrective Actions, two of which will require <br />the submittal of technical revisions to the permit within the next 30 days. The first <br />Corrective Action cited will be for the operator to secure access into the quarry by <br />posting warning signs around the perimeter of the quarry and physically blocking any <br />motorized or foot trails. The second Corrective Actions, and the first requiring the <br />submittal of a revision, will be to provide an approvable plan to monitor for movement of <br />the limestone blocks overhanging the slide area. The CGS report provides guidance <br />concerning movement monitoring. The third Corrective Action, and the second requiring the <br />submittal of a revision, is to propose a plan to conduct geologic, hydrologic and geo- <br />technical investigations of the quarry area. This plan must include specific timetables <br />for when the work will be achieved, anticipating that the results will likely be used to <br />formulate an entirely new mining and reclamation plan for the Pikeview Quarry. This will <br />be submitted to the division in the form of an amendment to the permit which will be the <br />fourth Corrective Action. <br />The Division was notified by Mr. Mac Shafer on February 18, 2009, that the MSHA report <br />will be finalized soon, and will be available upon receipt. On February 20, 2008 DRMS, <br />contacted MSHA again and inquired about the report. Mr. Dustan Crelly, Field Office <br />Supervisor, stated that to date they have not received the report, but once it is <br />finalized they will provide the Division a copy.