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11111 <br />• limestone and dolomite units as part of this unit. The limestone unit includes clay <br />seams, with one layer being about 6 inches thick and moderately continuous <br />across the area of the pit prior to mining. The clay seams and layers were deposited <br />during storms or other events that occurred in the ancient ocean during the <br />deposition of the limestone and dolomite. The unit could, and likely does, include <br />materials mapped by others as the Hardscrabble unit of the Leadville Formation <br />(Devonian aged), Williams Canyon Formation (Mississippian aged), Manitou <br />Limestone, and the Peerless Dolomite (Cambrian aged). The limestone exposed in <br />various portions of the quarry varies in color from a nearly pure white to gray to a <br />deep wine red. <br />The Manitou Limestone locally is physically divisible into four zones. The <br />upper zone, which is about 100 feet thick, is a softer limestone often containing <br />caverns and solution cavities and tending to be more variable than the lower zones. <br />It ranges in color from white to buff to a light gray. In some places, red inclusions <br />can be found. Separating the upper zone and lower middle zones is a zone of high <br />• calcium, gray colored, very hard limestone about 10 feet thick. In walls exposed in <br />the quarry, this zone of high calcium limestone can be seen as a darker gray band <br />with a fairly sharp upper and lower boundary. The lower middle zone, which is <br />approximately 150 feet thick, is composed of a hard limestone with much more <br />integrity than the upper zone. This part of the limestone has high hardness and <br />produces excellent aggregate. The color changes from light gray to light pink as the <br />depth increases. <br />The lowest dolomite portion of the formation tends to be quite variable in <br />thickness. Here it is about 28 feet thick and is quite similar to the formation at <br />Queens Canyon Quarry that was mostly mined out before that operation closed. <br />The formation is quite hard and tends to have a fairly large crystalline structure, <br />that is, large for a dolomite. The upper 8 to 12 feet is a light pink color, but as the <br />depth increases, the rock becomes darker. The lower 6 to 8 feet is often a deep <br />wine red. This rock is highly favored for landscaping and, in the past, was not only <br />extensively used in Colorado Springs, but also in Denver. <br />• <br />TRANSIT MIX AGGREGATES 9 <br />PIKEVIEW QUARRY SLOPE <br />CTLIT PROJECT NO. CS17341-125 <br />S:1CS17000-174991CS17341.0 0 011 2 512. Reports1CS17341-125-R1-Final.doc