Laserfiche WebLink
mining land use to be a water storage vessel and as such an inlet and out let structures are <br />required for such vessels. It also impacts the cost of reclamation, with that in mined, the <br />operator must submit a typical design with the option to change the design when an end <br />user is acquired. This will allow DRMS to calculate the required warranty for the typical <br />structures. <br />8) Operator states, Rip Rap maybe required or recommended along the reservoir <br />embankment toe for additional stability during rapid drawdown operations of the future <br />reservoir. Rip Rap along the dam crest may also be necessary for wave erosion." Unless <br />reservoir embankments are and dam crest are in bed rock, and the operator can <br />demonstrate that they will not be prone to erosion, it has been the Division's experience that <br />rip rap structure to be necessary to minimize erosion. Please provide a typical rip rap design <br />that will be implemented. The design must include the size of the rip rap from D10 TO D <br />maximum. The design can be changed at a later date to reflect use, It should also be <br />included in the warranty calculation. <br />9) Operator states, top soil will be salvaged and stockpiled as described in the previous <br />reclamation plan, the top soil is not expected to remain stockpiled for more than 2-4 years". <br />As noted earlier, if topsoil is stock piled for more than 180 days, it has to be seeded to <br />prevent erosion from taking place. <br />10) Under the granite quarry reclamation plan, the operator states "the proposed reservoir <br />layout would result in a future storage volume of appx. 8600 acre feet with surface area of <br />approximately 39 acres. The proposed reservoir will be lined with granite benched high <br />walls. Point plugging of any leakage will be performed through grouting if necessary, <br />although no major grouting is anticipated". Given the very limited geotechnical information <br />provided, the Division can not accept the statement with out some supporting data for your <br />conclusion. Please provide some technical data also support your conclusion. <br />11) Please provide a slope stability analysis to show the vertical mining slope for the <br />quarry will be stable. Please also include an analysis that shows the area above 5800 feet will <br />not have major slope failures during backfilling and reclamation at the proposed1.5:1 and <br />1:75:1 slopes. <br />V) EXHIBIT G Water Information <br />1) The operator states, monitoring well drilling has found 20 feet to more than 40 feet of <br />gravel above the water table or bed rock and 17 feet to more than 34 feet of gravel and sand <br />below the water table. For detailed information relating to groundwater impacts, see <br />attached groundwater modeling study". Where is the study, it was not included in the <br />amendment application. Please provide the study so DRMS can review and comment. <br />2) Under the reclamation narrative, you stated that the operator will not affect ground <br />water quality on or off the site". Are there any ground water wells with in 600 feet of the <br />permit area that are being utilized by adjacent land owners ? The operator provide a sprig <br />and seep survey in addition to wells with in 600 feet of the permit area. If there are such <br />items with in the 600 feet of the permit area, operator is required to document and explain <br />why they will not be impacted by the proposed operation and agree to mitigate impacts. <br />3) Does the GW ware study the operator conducted, shows changes in potentometic <br />surface due to pressure ? Has the operator conducted any pump well tests to show <br />fluctuations in ground water table ? Would the sand and gravel mining depth as proposed <br />5