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CONSIDERATION OF PERCHED AQUIFERS: Contrary to what the Cooley Exhibit D says, <br /> there is ground water present under some portions of the gravel deposit,but it is not everywhere and it <br /> is not a large volume. The dense and barely permeable Pierre Shale under the gravel is not level but <br /> was probably an erosion surface prior to the gravel being deposited as a result of erosion off of Pikes <br /> Peak and the Rampart Range following the various ice ages over the last few hundred thousand years. <br /> Thus original stream channels in the Pierre Shale persist under the gravel where a limited amount of <br /> groundwater accumulates and flows. Unfortunately, knowing where those areas are is extremely <br /> difficult to determine. Even the gravel itself does not have continuous depth or texture as it apparently <br /> was deposited by wide meandering streams of fairly high volume during glacial melting. And the <br /> gravel can vary widely with regard to particle size. <br /> It is very important to note that in some of the renewals of the SWSP, of which the approval <br /> letters from the Division of Water Resources are already in the possession of the Division, that it is <br /> stated that mining closer to the water than 2 feet will likely result in evaporative losses from the <br /> groundwater that, to be legal,need to be accounted for in the SWSP. Thus mining more closely than 2 <br /> feet from the base of the gravel deposit (if water is present)may result in a violation of the SWSP. <br /> Therefore, even though Cooley did not find water their rule of leaving 2 feet is still correct. <br /> From a long term water resource standpoint it is also important to keep these perched aquifers <br /> unexposed as much as possible to prevent losses from evaporation. It has become increasingly clear <br /> that"Climate Change"is not something in the future-it is here. Protection of water resources is even <br /> more critical now than back in the 1970's and 80's. The current Substitute Water Supply Plan limits <br /> exposed ground water to an existing 0.2 acre area. <br /> Consideration of Variations in Mineral Textures <br /> Back in the mid 1980's it was thought that this entire mesa-like structure was capped by a <br /> reasonably uniform layer of granitic gravels mostly derived from Pikes Peak Granite parent material <br /> located to the west and northwest of the site. Such is not actually the case. As mentioned before,these <br /> gravels are alluvium deposited by meandering streams or rivers, mostly during the ice ages, and <br /> therefore the depth and texture of the material can vary considerably. <br /> As can often be the case with such streams and rivers,pockets of fine material can be <br /> deposited in places and if the stream is aggradational these fine-textured spots can be buried by <br /> subsequent deposition of more coarse material, especially during floods. These pockets may have <br /> originally been islands or dissected portions of islands. These buried pockets of fine textured material <br /> may be a blend of some coarse gravel and a lot of fine sand, silt and clay that may have been <br /> Fountain Pit Technical Revision#3 - June 2022 M-1982-155 Mining Plan Page 10 of 22 <br />