Northern Integrated Supply Project, Proposed US Highway 287
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PALEONTOLOGICAL TECHNICAL REPORT: NORTHERN INTEGRATED SUPPLY PROJECT, PROPOSED U.S. HIGHWAY 287 REALIGNMENT LARIMER COUNTY, COLORADO Prepared for: ERO Resources Corporation 1842 Clarkson Street Denver, CO 80218 Prepared by: Paul C. Murphey, Ph.D. and David Daitch, M.S. Rocky Mountain Paleontology 4614 Lonespur Court Oceanside, CA 92056 303-514-1095; 760-758-4019 www.rockymountainpaleontology.com Prepared under State of Colorado Paleontological Permit 2006-5 August, 2006 TABLE OF CONTENTS 1.0 SUMMARY ........................................................................................................................ 1 2.0 INTRODUCTION .............................................................................................................. 3 2.1 Definition and Significance of Paleontological Resources ..................................... 3 3.0 METHODS ......................................................................................................................... 4 4.0 LAWS, ORDINANCES, REGULATIONS, AND STANDARDS .................................... 6 4.1 Federal..................................................................................................................... 6 4.2 State......................................................................................................................... 7 4.4 City .......................................................................................................................... 8 4.5 Private Lands .......................................................................................................... 8 4.6 Permits and Approvals ............................................................................................ 8 5.0 RESOURCE ASSESSMENT CRITERIA .......................................................................... 9 5.1 Probable Fossil Yield Classification ....................................................................... 9 6.0 PALEONTOLOGICAL RESOURCE ASSESSMENT ................................................... 10 7.0 AFFECTED ENVIRONMENT ........................................................................................ 11 7.1 Geology and Paleontology .................................................................................... 11 7.1.1 Lykins Formation ...................................................................................... 16 7.1.2 Undivided Jelm and Sundance Formations............................................... 16 7.1.3 Morrison Formation .................................................................................. 16 7.1.4 Dakota Group ............................................................................................ 17 7.1.5 Benton Group ............................................................................................ 18 7.1.6 Niobrara Formation ................................................................................... 18 8.0 EXISTING CONDITIONS ............................................................................................... 20 8.1 Museum Record Searches ..................................................................................... 20 8.2 Field Survey .......................................................................................................... 20 9.0 RECOMMENDATIONS .................................................................................................. 23 10.0 IMPACTS ANALYSIS .................................................................................................... 24 10.1 Direct Impacts ....................................................................................................... 24 10.2 Indirect Impacts .................................................................................................... 25 10.3 Cumulative Impacts .............................................................................................. 25 11.0 MITIGATION MEASURES ............................................................................................ 26 12.0 REFERENCES ................................................................................................................. 29 NISP EIS – Paleontological Resources i TABLES Table 1. Summary of Paleontological Laws, Ordinances, Regulations and Standards Applicable to the NISP U.S. 287 Realignment ........................................................8 Table 2. Summarized Paleontological Sensitivities of Geologic Units within the APE for the Preferred NISP U.S. 287 Western Alternative using the PFYC System (Map Abbreviations are from Braddock et al., 1988a, 1988b) .................10 Table 3. Previously Recorded Fossil Localities from within and Nearby the NISP Study Area. UCM, University of Colorado Museum of Natural History. It should be noted that fossil locality coordinates are not provided because they are considered sensitive data and are exempted from the Freedom of Information Act ......................................................................................................21 Table 4. Fossil Localities Discovered within the Field Survey for the Western Alternative of the NISP U.S. 287 Realignment. Fossil locality coordinates are provided in the confidential appendix ..............................................................21 FIGURES Figure 1. Aerial Photograph of a Portion of the APE for the NISP Showing the U.S. 287 Western (F&G) and Northern (J) Realignment Alternative Corridors. ............4 Figure 2. Geologic Map Showing the Approximate Location of the Southern Portion of the NISP U.S. 287 Western Alternative Northwest of Fort Collins, Larimer County, Colorado (from Braddock et al., 1988a) ....................................12 Figure 3. Geologic Map Showing the Approximate Location of the Northern Portion of the NISP U.S. 287 Western Alternative Alignment Northwest of Fort Collins, Larimer County, Colorado (from Braddock et al., 1988a). ......................13 Figure 4. Geologic Map Showing the Approximate Location of the Southern Portion of the NISP U.S. 287 Northern Alternative Alignment Northwest of Fort Collins, Larimer County, Colorado (from Braddock et al., 1988a). ......................14 Figure 5. Geologic Map Showing the Approximate Location of the Northern Portion of the NISP U.S. 287 Northern Alternative Alignment Northwest of Fort Collins, Larimer County, Colorado (from Braddock et al., 1988b). ......................15 APPENDIX Appendix 1 Confidential Fossil Locality Data ..........................................................................34 NISP EIS – Paleontological Resources ii 1.0 SUMMARY This is a paleontological assessment of two alternative realignments of U.S. Highway 287 (U.S. 287) for the Northern Integrated Supply Project (NISP). Alternatives F&G (the western alternative) and J (the northern alternative) are located within portions of sections 5-8, 17-20, and 29-32, T. 9 N., R. 69 W., and sections 5-8, and 17-18, T. 8 N., R. 69 W. (sixth Principal Meridian), on the USGS Laporte and Livermore 7.5’ topographic quadrangles in Larimer County, Colorado (see Figure 1). Although this report presents the results of the literature and record searches conducted for both realignment alternatives, it is focused on the preferred alternative of the Northern Colorado Water Conservancy District, the western alternative. This alternative, which is approximately six miles long, was surveyed for paleontological resources on January 23 and April 16, 2006. The survey corridor was approximately 200 feet wide (100 feet on either side of centerline). For this study, the Area of Potential Effect (APE) is defined as both the western and northern alternatives, for which literature and museum record searches were conducted. The survey corridor is defined as the preferred alignment for which a pedestrian field survey was conducted, and the width of the corridor was designed to encompass the maximum area of surface disturbance associated with highway construction. The paleontological sensitivities of the geologic units within the APE for the U.S. 287 western and northern realignment alternatives associated with NISP were evaluated by reviewing scientific and technical literature, geologic mapping and museum records. Based on the geologic mapping of Braddock et al. (1988a, 1988b), the study area contains six bedrock geologic units ranging in age from Permian to Cretaceous. These units include, from stratigraphically lowest to highest, the Upper Permian to Lower Triassic Lykins Formation, the Upper Triassic Jelm Formation and Upper and Middle Jurassic Sundance Formation undivided, the Upper Jurassic Morrison Formation, the Lower Cretaceous Dakota Group, the Lower Cretaceous Benton Group, and the Upper Cretaceous Niobrara Formation. All of these units are known to contain fossils of various taxonomic affinities and abundances across their distribution. At least four previously recorded fossil localities occur within or nearby the APE for NISP western and northern alignment alternatives. These include University of Colorado Museum localities 86050, from which dinosaur fossils were collected from the Morrison Formation; 87092, from which sharks teeth were collected from the Smoky Hill Member of the Niobrara Formation; and 88015, from which inoceramid clams were collected from the South Platte Formation of the Dakota Group. Locality 86050 is also the type locality for a species of freshwater sponge described by Dunagan (1999). Waage (1955) reported plesiosaur vertebrae in the Dakota Group northeast of Laporte and north