APPENDIX D PALEONTOLOGICAL RESOURCE ASSESSMENT REPORT Paleontological Resource Assessment Renaissance East Project City of Rialto San Bernardino County, California August 16, 2017 Prepared for: Kimley-Horn 401 B Street, Suite 600 San Diego, CA 92101 Prepared by: Department of PaleoServices San Diego Natural History Museum P.O. Box 121390 San Diego, California 92112-1390 Shelly L. Donohue, Paleontological Report Writer Thomas A. Deméré, Ph.D., Principal Paleontologist Executive Summary This paleontological resource assessment was prepared for the Renaissance East Project in the City of Rialto, San Bernardino County, California. The Project site is located northeast of the intersection of Renaissance Parkway and Ayala Avenue, immediately south of State Route 210. Proposed work at the site includes the construction of a new shopping, dining, and entertainment center that will include several restaurants and multi-tenant buildings, a 4-story hotel, as well as parking lots, driveways, and other ancillary features (e.g., signs, fencing, landscaping, utilities, etc.). Planned earthwork at the site has not been disclosed, but is presumed to include mass grading for creation of level building pads, and trenching for utilities. The purpose of this report is to identify and summarize paleontological resources that occur within the vicinity of the Project site, identify Project elements (if any) that may negatively impact paleontological resources, and provide recommendations to reduce any potential negative impacts to less than significant levels, if necessary. The report includes the results of an institutional records search and a paleontological field survey. Published geologic mapping for the Project site varies among authors, but generally indicates the site is underlain by Pleistocene- to Holocene alluvial deposits, and possibly eolian deposits. The paleontological field survey confirmed the presence of high-energy alluvial fan deposits at the site, but did not document eolian deposits. The alluvial deposits at the site consist of poorly sorted cobble to boulder conglomerate composed of subangular clasts, and are believed to extend at least 70 feet below grade at the Project site, based on observations of exposures in a quarry immediately south of the Project site. The alluvial deposits are believed to be Holocene in age (less than about 11,000 years old) at the surface, becoming older with depth. No recorded fossil collection localities are known from Holocene- or Pleistocene-age alluvial deposits within a 1-mile radius of the Project site, but fossils have been discovered in older Pleistocene-age alluvial deposits exposed elsewhere in western San Bernardino and Riverside counties. Recovered fossils primarily consist of large-bodied “Ice Age” mammals (e.g., ground sloth, mammoth, mastodon, camel, bison, dire wolf, sabertoothed cat, short-faced bear) and small terrestrial vertebrates (e.g., lizards, rodents, birds). Fossils are generally not known from Holocene-age sediments due to their relatively young geologic age. Following the paleontological potential guidelines outlined by the Society of Vertebrate Paleontology (2010), a low paleontological potential is assigned to all alluvial-fan deposits at the Project site. This assignment is based on the assumed Holocene age of the deposits, as well as the high energy nature of their deposition. A low paleontological potential is also assigned to any Pleistocene-age alluvial-fan deposits that may be present in the subsurface underlying the Holocene deposits. This assignment is based on the exceptionally coarse-grained nature of these deposits that suggests high energy deposition. Construction of the Renaissance East Project will probably involve only minor grading and trenching and thus will likely be confined to surficial alluvial fan deposits with a low paleontological potential. Based on these factors, construction is unlikely to create negative impacts to paleontological resources, and thus paleontological mitigation is not recommended for the Project. In the unlikely event that fossils are unearthed during construction (i.e., an inadvertent discovery), measures are provided to ensure proper collection and treatment of the fossils. Renaissance East Project - Paleontological Resource Assessment i Contents Executive Summary ........................................................................................................................................ i 1.0 Introduction ............................................................................................................................................ 1 1.1 Project Description and Scope of Work .............................................................................................. 1 1.2 Definition of Paleontological Resources ............................................................................................. 1 1.3 Regulatory Framework ....................................................................................................................... 4 1.3.1 San Bernardino County ............................................................................................................... 4 2.0 Methods .................................................................................................................................................. 5 2.1 Paleontological Records Search and Literature Review ..................................................................... 5 2.2 Paleontological Field Survey ............................................................................................................... 5 2.3 Resource assessment criteria: Paleontological Potential ................................................................... 5 2.3.1 High Potential .............................................................................................................................. 5 2.3.2 Undetermined Potential.............................................................................................................. 6 2.3.3 Low Potential ............................................................................................................................... 6 2.3.4 No Potential ................................................................................................................................. 6 2.4 Paleontological Impact Analysis ......................................................................................................... 6 3.0 Existing Conditions: Geologic Setting ...................................................................................................... 7 4.0 Results ..................................................................................................................................................... 7 4.1 Results of the Record Search and Literature Review ......................................................................... 7 4.1.1 Project Geology ........................................................................................................................... 7 4.1.2 Project Paleontology ................................................................................................................... 7 4.2 Results of the Paleontological Field Survey ........................................................................................ 8 4.3 Results of Paleontological Potential Analysis ..................................................................................... 9 4.4 Results of Paleontological Impact Analysis ......................................................................................... 9 5.0 Recommendations & Conclusions ........................................................................................................ 10 6.0 References ............................................................................................................................................ 11 Renaissance East Project - Paleontological Resource Assessment ii 1.0 Introduction 1.1 Project Description and Scope of Work This technical report provides an assessment of paleontological resources at the Renaissance East Project site in the City of Rialto, San Bernardino County, California (Figure 1). The approximately 7.68 acre Project site is bordered to the west by Ayala Avenue, to the south by Renaissance Parkway, to the north by State Route (SR) 210, and to the east by an existing residential development (Figure 2). Proposed work at the site includes the construction of a new shopping, dining, and entertainment center that will include a 10,486 square foot Cracker Barrel Restaurant, a 2,720 square foot Sonic Drive-in Restaurant, an additional 4,900 square foot drive through restaurant, a 4,300 square foot multi-tenant building, a 4,800 square foot multi-tenant building, a 52,742 square foot, 4-story hotel, as well as 423 parking spaces, driveways, and other ancillary features (e.g., signs, fencing, landscaping, utilities, etc.). Planned earthwork at the site has not been disclosed, but is presumed to include mass grading for creation of level building pads, and trenching for utilities. Because the proposed Project site occurs in an area underlain by native sedimentary rocks, it was determined that a paleontological resource assessment should be conducted to evaluate whether the proposed Project has the potential to negatively impact paleontological resources. Completion of this report fulfills mitigation measure CR-5 of the Renaissance Specific Plan Environmental Impact Report (EIR) for the Project.