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SENT BY~FSP&T, LLC, Q2 :11-20- 1 7:29AM EXECUTIVE SUMMARY • This overview is intended to serve as an summary of all geological considerations pertinent to the proposed Rio Grande Portland Cement Company (RGPCC) plant and properties south of Pueblo, Colorado. The Fort Heys Limestone Member (Niobrara Formation) was deposited in a shallow seaway which covered the Western Interior of North America during the Late Cretaceous period (-88.0 million years ago), The distribution of the characteristic interbedded white to light gray limestones and dark gray shale lnterbeds was controlled to a large extent by distance from the western shoreline of the ancient Cretaceous seaway. Over [he course of hundreds of thousands of years the accumtilated skeletons of calcium carbonate-secreting planktonic microorganisms (e.g. calcareous nannofossils) formed the nearly pure limestones visible in numerous surface exposures around the City of Pueblo. As these microscopic animals required relatively clear, sunlit seawater to survive, the limestone-dominated bcit of Fort Hays7ocks doesn't ezrend as far west as the ~nrllfOn of the "paleobeaeh. " 7ho location of these ancient shoreline deposits (present site for the town of Price, Utah) is an azea dominated by sandstone and mudstone rocks, with no limestone. [The most westerly outcrop of the Fort Hays Limestone is at Newcastle, CO -- a locality having no pure limestone beds due to the high amount of mud and silt from the western sediment source area.] The Fort Hays Membet at the RGPCC properties in Pueblo County, in contrast, are predominantly pure limestone, with very thin shale interbcds. The shales are free of excessive quantities of pyrite and associated sulfide minerals, due to the well-oxygenated nature of the seafloor during deposition of fire Fort Hays. Therefore, the azea immediately • southeast of Interstate 1-ZS that has been drill core sampled and tested by RGPCC contains much less orgaic carbon-bearing, fine-grained mudroek than the foothills to the west, an observation easily verified by visual analysis of the numerous Fort Hays cores presently archived in Pueblo. Geochemical testing of these limestones (from RGPCC lands) indicates that they contain some of the lowest concentrations of kerogens and sulfur-based by-products of any carbonate rock presently exploited as a resource by the cement industry in Mexico, Canada, and the United States- Findings of this report are summarized in the following four main poinu: 1. the proposed RGPCC plant /quarry site in Pueblo County, Colorado is within the "central limestone-dominated" belt of the Fort Hays Member (itt terms of the total geographic distribution of the Fart Hays Member); in contrast, at least two extant cement operations in Colorado are located in and utilizing less pure Fort Hays resources from the "western argillaceous-dominated" belt); • 1992