Laserfiche WebLink
that any changes to the high wall and bench configuration, other than what is submitted <br />with this amendment application has to be submitted in the form of a Technical Revision to <br />the permit, so our engineering staff can review and comment. <br />IV) EXHIBIT E Reclamation plan. <br />1) The operator proposes to change the post mining land use Range Land/ wildlife habitat <br />to empty water storage vessels for both the Sand and gravel pit and the quarry. The sand <br />and gravel portion of the pit slopes is being proposed to be lined with 15 ft wide clay <br />blanket at a 3:1 slope or gentler. How thick is this blanket ? What are the steps that the <br />operator going to take to prepare the slopes prior to placing these liners ?What is the <br />QA/QC procedure that will be implemented for placement of these blankets? Are there any <br />kind of manufacturer specifications for placement of these blankets? The operator does not <br />have the water rights to immediately utilize these vessels as water storage after it is <br />reclaimed as such. What is the life expectancy of the liner prior to degradation, if it stays <br />empty? Please explain. The pond design will require an approval from the State Engineer to <br />make sure it meets their requirement for allowable leakage. Please provide their approval <br />for the proposed design. <br />2) The sand and gravel reservoir design includes a 15 feet high dam which fall under the <br />jurisdictional authority of the State Engineer as you correctly pointed out. Please provide <br />the signed approval for this dam to DBMS, prior commencement mining. <br />3) In your narrative, you stated that the proposed liner design includes lining the side <br />slopes and 1/3 of the pit bottom with on site clays sandstone and shale. According to your <br />statement, the pit bottom contains three bed formations. The bed rock for the western 2/3 of <br />the pit bottom is the clay sandstone and shale formations. Geotechnical testing was <br />performed by J.A Cesare and Associates in 2006. The result of the testing gives reason to <br />believe the material will significantly seal the reservoir to meet the State Engineer's <br />requirement. Please provide the data to support your conclusions. <br />4) The operator states, " The currently proposed liner consists of a 15 feet wide clay <br />blanket to be constructed with 0.5H:1V side slopes and placed along the mining high walls. <br />The clay liner will be keyed into the bedrock. Design specification and quality control <br />procedures will be used during construction of the clay liner to meet the State Engineer's <br />Office performance standards for permeability. As requested earlier, DRMS will need the <br />SEO approval letter in addition to the QA/ QC procedure for installation of the liner. The <br />Division understand that the final pi slopes for the reservoir to be 3:1 or gentler below water <br />line. <br />5) It is the understanding of the Division that reclamation of the reservoir embankments <br />to be concurrent with mining, with reclamation activities following approximately 1000 feet <br />behind mining. If it is not, please clarify. <br />6) The operator proposes to compact the backfill material to 95 Procter compaction. Please <br />provide the testing frequency and how such a compaction will be achieved to meet the <br />proposed standards. <br />7) Operator states, "Inlet and outlet facilities for future use of the reservoir, as well as the <br />spill ways have not been designed at this time. Once an end user is identified, design of the <br />facilities could be implemented during the reclamation phase. The reclamation of the <br />structures is not required to restore the land to a beneficial use". The Division understands <br />what the operator is saying, however, it is the operator who proposes the change to the post <br />4