Paleontological Resources Assessment Technical Report

Rail Tie Wind Project Albany County, Wyoming

Prepared for:

ConnectGen Albany County LLC

April 2020

1

Business Confidential ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project

TABLE OF CONTENTS

1 INTRODUCTION ...... 1 1.1 Project Background ...... 1 1.2 Analysis Area ...... 1

2 REGULATORY FRAMEWORK ...... 2 2.1 Federal Regulations ...... 2 2.1.1 National Environmental Policy Act ...... 2 2.2 State Regulations ...... 2 2.2.1 Wyoming Industrial Development Information and Siting Act ...... 2 2.2.2 Wyoming Antiquities Act ...... 2

3 METHODOLOGY ...... 3 3.1 Desktop Review ...... 3 3.1.1 Paleontological Resource Assessment Criteria ...... 3

4 EXISTING ENVIRONMENT ...... 6 4.1 Geologic Background ...... 6 4.2 Paleontology of the Laramie Basin ...... 8

5 DATABASE AND LITERATURE REVIEW RESULTS ...... 9

6 POTENTIAL EFFECTS ANALYSIS ...... 10 6.1 Applicant-Proposed Environmental Protection Measures ...... 11

7 LITERATURE CITED ...... 14

LIST OF TABLES

Table 1: Paleontologically Sensitive Geologic Units in the Project Area...... 9 Table 2: Previously Identified Material from the Casper and Fountain Formations ...... 9 Table 3: Proposed Environmental Protection Measures Related to Paleontological Resources for the Rail Tie Wind Project ...... 12

LIST OF FIGURES

Figure 1: Geologic Map with Project Area Overlay Figure 2: Stratigraphic Column

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1 INTRODUCTION At the request of ConnectGen Albany County LLC (ConnectGen) and Tetra Tech, Inc. (Tetra Tech), PaleoWest has prepared this Paleontological Resources Assessment technical report for the Rail Tie Wind Project (Project). This document is intended to provide reviewing regulatory agencies with information on the geologic units within the Project Area and their potential for producing scientifically significant paleontological resources, including vertebrate, invertebrate, plant, and/or trace fossil material. The history of in the Laramie Mountains is discussed, as well as the potential impact of the Project on paleontological resources.

1.1 Project Background The Project is located in southeastern Albany County, Wyoming, and encompasses approximately 26,000 acres of ranchland on private and state lands near Tie Siding, Wyoming (Project Area; Figure 1). The Project would include up to 149 wind turbine generators, each ranging between 3.0 to 6.0 megawatts (MW) in size, with a combined maximum generating capacity rating of 504 MW. The Project proposes to interconnect to the existing transmission system of the Western Area Power Administration (WAPA) via the Ault-Craig 345-kilovolt (kV) transmission line, which runs through the Project Area.

For construction planning and site optimization, the Project consists of two separate phases, each approximately 252 MW. Construction of the Project is expected to begin in 2021, and both phases could be fully operational by the end of 2022. As is common with large wind projects, the Project may require two years to fully construct. If additional time is required to facilitate construction, it is anticipated that the first 252 MW phase would be completed and fully operational by the end of 2022, and second phase operational in 2023.

1.2 Analysis Area A desktop survey was performed for the Project Area along with a 0.5-mile buffer on all sides. The buffered area will not be directly affected by the proposed undertaking, but is provided in this desktop study only as a reference for the broader area, providing an assessment of the potential for fossil-bearing strata in the immediate vicinity of the Project Area. Analysis focused on bedrock outcrops of sedimentary strata that may have the potential to hold fossil material. The buffer was utilized to determine if there were other sedimentary units identified elsewhere as containing fossil material that could have shallow subcrop within the Project Area that could be intersected during any ground-disturbing activities.

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2 REGULATORY FRAMEWORK

2.1 Federal Regulations

2.1.1 National Environmental Policy Act The National Environmental Policy Act (NEPA) requires the disclosure of potential environmental impacts for projects requiring a federal action, through either a Categorical Exclusion, Environmental Assessment, or Environmental Impact Statement (EIS), as well as a process of public and agency review and comment.

WAPA’s action on the interconnection request is considered a federal action subject to NEPA, in accordance with Council on Environmental Quality (CEQ) regulations for implementing NEPA and Department of Energy NEPA Implementing Procedures (40 CFR Parts 1500−1508, 10 CFR Part 1021). This technical report provides information to assist WAPA in the analysis of the potential effects to the natural and human environments associated with approving or denying the interconnection request.

2.2 State Regulations

2.2.1 Wyoming Industrial Development Information and Siting Act The Wyoming Department of Environmental Quality (WYDEQ) Industrial Siting Division (ISD) administers the Wyoming Industrial Development Information and Siting Act (Act; Wyoming Statute § 35-12-101:119) and the Rules and Regulations of the Industrial Siting Council (ISC), Chapters 1 and 2. The Act is designed to protect Wyoming’s environmental, social, and economic fabric of communities from unregulated large-scale industrial development. By consolidating the review of 19 independent state agencies into one comprehensive permitting process, the Act offers a thorough analysis of the development’s impacts to the public and affected agencies.

Pursuant to the Act, all wind energy projects consisting of 30 or more turbines (in all planned phases of the installation) and/or exceeding the statutory threshold construction cost amount of $222.8 million are subject to review and approval by the ISC. For facilities permitted under Wyoming Statute (WS) § 35-12–102(a)(vii)(E) and (F), a site reclamation and decommissioning plan and a financial assurance plan are required pursuant to WS § 35-12-105(d) and (e).

As part of the review and approval process, the ISC requires submittal of an application that outlines the evaluation of potential project impacts and mitigation measures related to environmental, social, and economic resources.

2.2.2 Wyoming Antiquities Act Section 36-1-114 through Section 36-1-116 of the Wyoming Antiquities Act protects archaeological and paleontological material on State lands. Any excavation of paleontological deposits in the State of Wyoming on any State lands requires authorization to be obtained from the State Board of Land Commissioners.

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3 METHODOLOGY

3.1 Desktop Review A desktop review was performed by PaleoWest’s Senior Paleontologist, Dr. Kate Zeigler, who has two decades of experience in paleontology and geology. She has carried an annual Bureau of Land Management mitigation permit for eight years in New Mexico and has experience in multiple aspects of mitigation paleontology in the western U.S. PaleoWest reviewed publicly available information contained on websites, databases, maps, and scientific literature to identify paleontological resources within the Project Area, including the following:

. Geologic map of Wyoming (Love and Christiansen 1985) . Geologic maps of the Red Buttes, Sherman Mountains West, Best Ranch, and Dale Creek quadrangles (Ver Ploeg 2007; Ver Ploeg and McLaughlin 2010; Ver Ploeg et al. 2011; Carnes et al. 2013) . Paleontologic Resources Analysis Letter Report for the Hermosa West Wind Farm Project in southeast Albany County, Wyoming. (Erathem-Vanir Geological Consultants 2010) . Database search, University of Wyoming Department of Geology & Geophysics (Vietti 2019) . Relevant scientific literature for geology and paleontology of the Laramie Basin

3.1.1 Paleontological Resource Assessment Criteria Occurrences of paleontological resources are closely tied to the geologic units (i.e., formations, members, or beds) that contain them. Thus, the probability for finding paleontological resources can be broadly predicted from the geologic units present at or near the surface, and geologic maps of a project area can be used for assessing the potential for occurrence of paleontological resources.

The BLM utilizes the Potential Fossil Yield Classification (PFYC) system, which is meant to provide baseline guidance for predicting, assessing, and mitigating paleontological resources. The PFYC system is considered an initial point in the prediction analysis and should be used in conjunction with geologic maps of the area and searches of paleontological resource locality databases to assist in determining the need for site-specific assessment or further mitigation actions (BLM IM 2016-124).

The PFYC system classifies geologic units based on the relative abundance of vertebrate fossils or scientifically significant invertebrate, plant or trace fossils, and their sensitivity to adverse impacts. A “significant” fossil is defined as fossil remains considered to be of scientific interest and this definition includes most vertebrate fossil material, fossil trackways, trace fossils, rare or unusual invertebrates or plant fossils. Scientific importance is determined by 1) the rarity of a fossil or if it represents a previously unknown , 2) the quality of preservation (e.g., it is of remarkably high quality), 3) preservation of a previously undocumented anatomical feature, 4) determination that the fossil material provides new information that is relevant to our understanding of the history of life on Earth and/or 5) potential for educational and/or recreational

3 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project value. A paleontological resource that would be considered to not have scientific significance includes resources that 1) lack geologic context or provenance, 2) have poor preservation or are badly damaged by erosion, and/or 3) are abundant in the geologic record (and thus redundant). In the PFYC system, a higher-class number indicates a higher potential for significant fossil presence and/or adverse impact. This classification is applied to the geologic formation, member, or other distinguishable rock unit, preferably at the most detailed mappable level. The relative abundance of significant localities is intended to be the major determinant for the class assignment. The PFYC System comprises the following classes:

Class 1—Very Low. Geologic units that are not likely to contain recognizable paleontological resources. Units assigned to Class 1 typically have one or more of the following characteristics:

. Geologic units are igneous or metamorphic, excluding air-fall and reworked volcanic ash units. . Geologic units are Precambrian in age. . Management and mitigation concerns for Class 1 are generally negligible or not applicable. There may be very rare circumstances where an unanticipated occurrence is documented (e.g., a mapped geologic unit contains an unmapped fossiliferous unit within it). If a Class 1 designation is applied to an area, there is no further analysis; however, an unanticipated discoveries plan should still be implemented.

Class 2—Low. Geologic units that are not likely to contain paleontological resources. Units assigned to Class 2 typically have one or more of the following characteristics:

. Field surveys have verified that significant paleontological resources are not present or are very rare. . Units are generally younger than 10,000 years before present. . There are recent aeolian deposits. . Sediments exhibit significant physical and chemical changes (i.e., diagenetic alteration) that make fossil preservation unlikely. . For Class 2 assessments, management concerns are generally minimal except where paleontological resources are known to occur. Mitigation would thus only be needed where these resources have been found to exist and effectively is managed on a case-by-case basis. A Class 2 assignment may not lead to further analysis unless resources are known or found to exist. As with Class 1, an unanticipated discoveries plan should be in place.

Class 3—Moderate. Sedimentary geologic units where fossil content varies in significance, abundance, and predictable occurrence. Units assigned to Class 3 have some of the following characteristics:

. Units are marine in origin with sporadic known occurrences of paleontological resources. . Paleontological resources may occur intermittently, but abundance is known to be low. . Units may contain significant paleontological resources, but these occurrences are widely scattered.

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. The potential for an authorized land use to impact a significant paleontological resource is known to be low to moderate.

Management plans for a Class 3 designation will be moderate and may include literature reviews, database searches, pre-project pedestrian surveys, on-site monitoring, area avoidance, among other strategies. Management is generally more moderate than for Class 4 or 5 due to the known presence of significant resources being low. Mitigation would be based on the proposed activity and extent of disturbance and may require assessment by a qualified paleontologist to identify potential for scientifically significant resources in the area.

Class 4—High. Geologic units that are known to contain a high occurrence of paleontological resources. Units assigned to Class 4 typically have the following characteristics:

. Significant paleontological resources have been documented but may vary in occurrence and predictability. . Surface-disturbing activities may adversely affect paleontological resources. . Rare or uncommon fossils, including nonvertebrate (such as soft body preservation) or unusual plant fossils, may be present. . Illegal collecting activities may impact some areas. . An area designated as Class 4 will be subject to significant management/mitigation strategies and will depend on the nature of the project as proposed. Field assessment by a qualified paleontologist will be needed to assess the conditions in the proposed Project Area. Due to the presence of significant resources, the probability of impact is higher and requires mitigation plans that are appropriate. Detailed literature and database review are required as well as a detailed field assessment due to concerns regarding removal/penetration of potentially protective deposits of soil/alluvium, the concerns for increased erosion due to ground disturbance and/or an increase in potential for looting of resources now that access to fossil material is easier. On-site monitoring and/or spot- checking during ground disturbing would be necessary and in some cases, avoidance of paleontological resources may be required.

Class 5—Very High. Highly fossiliferous geologic units that consistently and predictably produce significant paleontological resources. Units assigned to Class 5 have some or all of the following characteristics:

. Significant paleontological resources have been documented and occur consistently. . Paleontological resources are highly susceptible to adverse impacts from surface- disturbing activities. . Unit is frequently the focus of illegal collecting activities. . As the highest category of the PFYC system, class 5 areas will require a high level of management. An in-field survey is almost always a requirement and may lead to mitigation before and/or during ground-disturbing activities. The probability in these areas of discovery of fossil material is high and thus a detailed in-field assessment and on-site

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monitoring are usually required. Other strategies may include avoidance of resources, preservation of resources via controlled access, and/or special management designations.

Class U—Unknown Potential. Geologic units that cannot receive an informed PFYC assignment. Characteristics of Class U may include the following:

. Geological units may exhibit features or preservational conditions that suggest significant paleontological resources could be present, but little information about the actual paleontological resources of the unit or area is known. . Geological units represented on a map are based on lithologic character or basis of origin but have not been studied in detail. . Scientific literature does not exist or does not reveal the nature of paleontological resources. . Reports of paleontological resources are anecdotal or have not been verified. . Area or geologic unit is poorly or under studied. . BLM staff has not yet been able to assess the nature of the geologic unit. . Class U areas, due to the unknown nature of the resources, will end up requiring a higher degree of management. Field surveys are usually required in order to assess the potential of an unknown area. It should be noted that unknown may simply indicate the area or geologic unit in question have not been well surveyed and thus field assessment is needed to determine the true potential of the area or geologic unit.

4 EXISTING ENVIRONMENT

4.1 Geologic Background The Project Area is located in the Laramie Mountains, southeast of the town of Laramie. Much of the area includes exposures of Precambrian crystalline rocks, the Sherman Granite, with north- south trending outcrop belt to the west of - sedimentary rocks (Love and Christiansen 1985; Figure 1). These strata include (in ascending age order) the Pennsylvanian Fountain Formation and the Pennsylvanian-Permian Casper Formation (Figure 2). To the west is the Laramie Basin, a Laramide-age syncline that includes approximately 7,000 feet of Paleozoic and Mesozoic strata, as well as well-developed Tertiary and Quaternary deposits.

During the Pennsylvanian and Permian periods, much of western North America developed a series of mountain uplifts interspersed with deep basins. This mountain-building event is termed the Ancestral Rocky Mountains and resulted in thick sequences of both marine and terrestrial deposits in the basins and along the flanks of the mountain blocks. During the Permian Period, as the seaway retreated from the region, the resulting depositional sequences became more terrestrial in nature. By the beginning of the Mesozoic Era, deposits record primarily terrestrial deposition, although locally thick gypsum beds indicate evaporative lakes and/or tidal flat environments. The strata in the area were deposited in a mosaic environment of fluvial, lacustrine, and aggradational fans. By the beginning of the Late epoch, the

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Cretaceous Interior Seaway flooded much of central North America, resulting in thick sequences of black shale and limestone, with some sandstone beds representing beach deposits and/or delta deposits. By the end of the Cretaceous Period, the modern Rocky Mountains were beginning to develop as the Seaway retreated. Rocky Mountain uplift continued into mid-Tertiary time, resulting in much of the modern landscape observed today. As uplift ceased, the deep valleys developed between ranges began to fill in with erosional material off the mountain blocks.

In the Project Area, the geologic units of concern for paleontological resources include the Pennsylvanian Fountain and Casper formations (Figures 1 and 2). The eastern and central portions of the Project Area are situated on outcrops of Precambrian Sherman Granite (map unit Ys), with local outcrops of Precambrian metasedimentary and metavolcanics rocks (map unit Xsv). The western portion overlies localized outcrops of Pennsylvanian-Permian sedimentary strata of the Fountain and Casper formations (map unit IPPcf) draped with Quaternary gravel, pediment, and alluvial fan deposits (map unit Qt) (Love and Christiansen 1985; Ver Ploeg 2007; Ver Ploeg and McLaughlin 2010; Ver Ploeg et al. 2011; Carnes et al. 2013).

Precambrian crystalline rocks are present in the eastern and central portions of the Project Area and include exposures of the Sherman Granite, a 1.4-billion-year-old batholith composed of biotite hornblende granite. Higher-resolution mapping also indicates the presence of a porphyritic granite, considered an intermediate phase between the Sherman Granite and the Lincoln Granite, a slightly younger intrusion to the east of the Project Area (Ver Ploeg et al. 2011; Carnes et al. 2013). Additional small exposures of Precambrian metasedimentary and metavolcanics rocks are present and can include gneiss, marble, schist, and amphibolite.

The Fountain Formation is 10 to 400 feet thick and composed of red, pink, and purple arkosic, cross-bedded, fine- to coarse-grained sandstone with beds or lenses of conglomerate, fossiliferous limey sandstone, siltstone, shale and thin limestone beds (Ver Ploeg 2007; Ver Ploeg and McLaughlin 2010; Ver Ploeg et al. 2011; Carnes et al. 2013). Mapped together with the Casper Formation in the western Project Area, it thins to the north and interfingers with the overlying Casper Formation, such that the two units are generally mapped together in many places. The Fountain Formation represents deposition in alluvial fans and/or aggradational fan systems shedding off the Precambrian granite-cored uplifts of the Ancestral Rocky Mountains. During the Pennsylvanian Period, the shallow seaway that had covered much of western North America was retreating, resulting in a mosaic landscape of shallow ocean, nearshore and beach, and fully terrestrial depositional environments.

The Casper Formation includes 10 main limestone beds separated by sandstone-dominated units that range from 60 to 400 feet thick across its outcrop belt, although it thins to the south (Ver Ploeg 2007; Ver Ploeg and McLaughlin 2010; Ver Ploeg et al. 2011; Carnes et al. 2013). The limestone beds are buff to purplish gray, may be locally dolomite, are usually micritic, and can be locally fossiliferous. The sandstone units are buff to reddish, calcareous to quartzitic, and very fine- to coarse-grained subarkosic sandstone with large-scale festoon cross bedding. The limestone beds average 5 to 10 feet thick, although limestone 3 is the thickest and most prominent

7 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project of these, at approximately 30 to 40 feet thick. The intervening sandstone beds range from 65 to 150 feet thick. The lowest sandstone unit is gradational with the underlying Fountain Formation and contains some very thin limestone beds. The Casper Formation is divided into five informal members, based on aquifer packages determined by the sandstone units. From oldest to youngest the members are the alpha, beta, gamma, delta, and epsilon members, with limestone 3 occurring near the top of the alpha member. By the Permian Period, the seaway had fully retreated, and southeastern Wyoming included alluvial fan/aggradational fan systems and fluvial and lacustrine depositional environments. The Casper Formation is overlain by the Permian Satanka Shale.

Quaternary deposits in the western portion of the Project Area include Pleistocene alluvial fan and terrace deposits (Ver Ploeg et al. 2011), which are composed of poorly sorted clay to gravel deposits with occasional boulders and cobbles primarily composed of local older bedrock units. In general, these deposits are very coarse grained, indicating mostly high-energy depositional environments such as alluvial fans and debris flows shedding westward off the Laramie Mountains into the Laramie Basin.

4.2 Paleontology of the Laramie Basin In general, the Fountain and Casper formations produce invertebrate fossil material from the limestone beds in both units (Tables 1 and 2) and would be considered PFYC 3 (BLM, 2002). The Fountain Formation limestone beds include foraminifera, specifically, the fusulinid Profusulinella, which have been used to determine the depositional age of the unit (Hoyt and Chronic 1962). When the Casper Formation was named and described by Darton and Siebenthal in 1909 (Darton and Siebenthal 1909), they did not recognize the Fountain Formation as a separate unit. They recorded a number of invertebrate fossils from the combined Fountain-Casper Formation, including , bivalves, gastropods, nautiloids, and a single echinoid. Miller and Thomas (1936) greatly expanded the fauna of the Casper Formation and clarified some of the identifications made by Darton and Siebenthal (1909). Their research expanded the nautiloid fauna and added a species of trilobite. Many of the genera of invertebrates observed in the Casper Formation are relatively common in Pennsylvanian faunal associations, but some are not commonly found in the Laramie Mountain area (Pederson 1954).

To the south in Colorado, the Fountain Formation preserves a diverse fauna of brachiopods, gastropods, and . In addition, rare fish bone fragments and amphibian footprints have been identified from terrestrial portions of the sequence in the area around Boulder (Jennings 1980; Murphey and Zubin-Stathopoulos 2018).

The Pleistocene deposits in the Project Area are generally considered unlikely to preserve fossil material because the majority of the depositional units are very high energy and would best be considered as PFYC 2. However, Hager (1972) documented a unique faunal assemblage in Larimer County, the Chimney Rock natural trap, where 33 species of vertebrates were

8 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project trapped in a deep circular erosional feature in the Casper Formation that eventually was filled in with Pleistocene sediments.

Table 1: Paleontologically Sensitive Geologic Units in the Project Area PFYC Geologic Unit Age Map Abbreviation Example Fossil Material Class Older alluvium Pleistocene Qoa Marten, fox, felids, vulture, 2 among others. Casper Formation Middle-Upper IPPcf (also may be Fusulinids, ostracods, 3 Pennsylvanian to designated as PIPcα on brachiopods, bivalves, Permian 1:24,000 scale maps) gastropods, nautiloids, trilobites, echinoids Fountain Formation Pennsylvanian IPPCF Fusulinids 3

Table 2: Previously Identified Fossil Material from the Casper and Fountain Formations Phylum Geological Unit Foraminifera: Fusulinidae Profusulinella Fountain Formation Triticites Casper Formation Brachiopoda Derbyia, , Productus, Meekella, Orthotetes Casper Formation : Aviculopecten, Myalina, Plurophorus, Schizodus, Pinna Casper Formation Mollusca: Patellostium, Euphemus, , Soleniscus, Casper Formation Murchisonia, Straparollus Mollusca: Cephalopoda Tainoceras, , Stenopoceras, Orthoceras, Casper Formation Psuedorthoceras, Mooreoceras, Coloceras, Metacoceras, Solenochilus Arthropoda: Trilobita Ameura Casper Formation Echinodermata: Echinoidea Archaeocidaris Casper Formation

5 DATABASE AND LITERATURE REVIEW RESULTS A search of the University of Wyoming Geological Museum database yielded no localities recorded for any of the townships spanned by the Project Area (Vietti 2019). While this does not mean there will not be fossils observed in the Project Area, these may be very common marine fossils in limestone beds that are not considered scientifically significant. The Fountain Formation in general does not produce significant fossil material in southeastern Wyoming, but the red arkose sandstones and shales have produced rare vertebrate fossil material and trackways in Colorado, suggesting that there may be potential for such material in the Project Area. The Casper Formation has yielded numerous invertebrate fossils of many genera common to Pennsylvanian marine deposits throughout the western United States. Many of the fauna described for the Casper Formation come from outcrops exposed in canyons on the west flanks of the Laramie Mountains to the north of the Project Area.

In addition, a previous analysis of paleontological resources for the Hermosa West Wind Energy Project, which encompassed lands within the western portion of the Project Area, indicated that

9 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project no fossils of any kind were discovered during a field inspection of the site (although the site inspection was hampered by deep snow cover), and that deep regolithic soil and thin loess deposits covered most of the exposures of the Casper Formation within the proposed project site (EVG 2010). The study also noted that the Casper Formation is very poorly exposed within the areas observed, and that none of the outcrops observed contain limestone beds from which Casper Formation fossils have been previously recovered (EVG 2010).

6 POTENTIAL EFFECTS ANALYSIS Direct impacts to fossil materials occur not only as a result of ground-disturbing activities but also the illegal removal of fossil material by persons who may observe fossil material during construction. The potential for direct adverse impacts on scientifically significant fossil material in the subsurface is controlled by the depth to and thickness of fossiliferous bedrock combined with the depth of expected construction-related activities. Additionally, the lateral extent of both bedrock and ground-disturbing activities affect the potential for adverse impacts to fossil material. There is no reliable method for predicting the possible position of fossil material within a bedrock unit. Depending on the depositional environment, fossils may be relatively equally distributed throughout the unit (e.g., in marine units) or may be concentrated in one area (e.g., bones entrained in a river channel). Potential direct impacts are most likely to impact fossil materials in PFYC 3 areas that may potentially be present in the Project Area. Impacts may affect an unknown quantity of material, given the uncertainties related to preservation and distribution of fossil material in a geologic unit.

Potential adverse impacts during post-construction normal operations of the turbines in the Project Area could result from routine maintenance-related activities such as travel along access routes and activities around the footprints of each tower. Potential erosion of exposed soil and/or outcrop within the Project Area may eventually expose fossil materials that may otherwise have remained buried beneath the surface.

Based on the results of the desktop review, which included local and regional geologic mapping, a University of Wyoming Department of Geology and Geophysics paleontological collections database search, and a review of pertinent scientific literature, the presence of significant paleontological resources within the Project Area is moderate to low. The Fountain Formation has produced very little fossil material, and fossiliferous areas documented in the Casper Formation all occur approximately 10 miles to the north of the Project Area in and around Gilmore Canyon (or Gilmore Gulch on topographic maps). The presence of fossiliferous areas within the Casper Formation to the north suggests a probability of fossiliferous subcrop in the Project Area. In addition, Quaternary units in the western portion of the Project Area have not been identified as having a high probability of fossil material. In addition, a survey performed in 2010 (EVG 2010) did not document any fossil material to the east of the current Project Area. The results of the desktop survey, EVG’s prior survey and the nature of construction methods to be used suggest that the potential that any scientifically significant fossil resources will be compromised during development of the Project Area is remote.

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Although the presence of significant paleontological resources within the Project Area is unlikely, in order to avoid potential direct impacts to paleontological resources from Project activities, a pedestrian survey will be conducted by a qualified professional paleontologist (e.g., a professional paleontologist holding all appropriate permits as required for the State of Wyoming) on outcrops of the Pennsylvanian Fountain Formation and Pennsylvanian-Permian Casper Formation within areas proposed for ground disturbance prior to Project construction.

In addition, development of an Unanticipated Discoveries and Mitigation Plan (UDMP) would further assist in avoidance and minimization of potential impacts to paleontological resources by providing a means of identifying, protecting, and mitigating any unexpected fossil discoveries made during the course of construction in the Project Area.

6.1 Applicant-Proposed Environmental Protection Measures ConnectGen has developed Environmental Protection Measures (EPMs) that when implemented would avoid or minimize adverse effects to environmental resources from construction, operations and maintenance, and decommissioning of the Project. The EPMs listed in Table 3 below would both directly and indirectly avoid or reduce potential effects to paleontological resources.

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Table 3: Proposed Environmental Protection Measures Related to Paleontological Resources for the Rail Tie Wind Project

Resource Implementation Category Measure Preconstruction Construction Operations Decommissioning General GEN-1 The Project will be designed, constructed, and operated in X X X X compliance with Albany County Zoning Regulations (as amended) and Albany County Wind Energy Siting Regulations. Construction and operations activities will comply with all federal, state, and county environmental regulations, as applicable. GEN-2 The Project will delineate environmentally sensitive areas (e.g. X X X X wetlands, waters, habitats) located within or adjacent to the Project Area and will identify those locations in construction planning documents. Construction and operations personnel will be informed of the appropriate practices that may be applicable to avoid or minimize impacts to these areas. GEN-3 Construction travel will be restricted to existing roads and X permanent or temporary access roads identified in the final Project Site Plan. Geology and Soils GEO-1 Temporary ground disturbance activities will be limited to the X minimum amount necessary in order to safely construct project facilities. Paleontological Resources PALEO-1 Prior to construction, a pedestrian survey will be conducted X by a qualified professional paleontologist in areas of high potential for fossil occurrence where ground disturbance activities are proposed to occur. PALEO-2 A Paleontological Unanticipated Discoveries and Mitigation X X Plan will be prepared that outlines appropriate actions in the event of an unanticipated discovery of fossils, including sampling investigation and reporting, and if desired by the landowner, museum storage coordination for any specimen or data recovered.

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Resource Implementation Category Measure Preconstruction Construction Operations Decommissioning PALEO-3 Construction personnel involved with earth-moving activities X X will be informed of the possibility of encountering fossils, how to recognize fossils, and proper notification procedures. This worker training will be prepared by a qualified paleontologist and will be presented to all construction personnel during orientation. PALEO-4 If fossils are discovered in an active construction area, work X would be stopped at that location and the construction project manager would be immediately notified.

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7 LITERATURE CITED BLM (Bureau of Land Management). 2016. Potential Fossil Yield Classification (PFYC) System for Paleontological Resources on Public Lands. Instructional Memorandum No. 2016- 124.

_____. 2002. Potential Fossil Yield Classification Data compiled by D. Hanson, Regional Paleontologist, BLM Wyoming State Office, which include data from Ross Secord, Northern Great Plains Probable Fossil Yield Classification Report, University of Wyoming, 1996; Peter Robinson, David Daitch, and Jennifer Haessig, Fossil Vertebrate Localities of Southwestern Wyoming: A Literature Search, Locality Record, and Formation Evaluation, Univ. of Colorado Museum, BLM Contract KAA 000002, 2002.

_____. 2007. Instruction Memorandum: Potential Fossil Yield Classifications (PFYC) System for Paleontological Resources on Public Lands, 12 p.

Carnes, J. D., Lynds, R. M., Gregory, R. W., and Ver Ploeg, A. J. 2013. Preliminary geologic map of the Dale Creek quadrangle, Albany County, Wyoming. Wyoming State Geological Survey Open-File Report 2013-2, 33 p., 1:24,000 scale, 1 sheet.

Darton, N.H. and C.E. Siebenthal. 1909. Geology and mineral resources of the Laramie Basin, Wyoming: A preliminary report. U.S. Geological Survey Bulletin 364, 89 p.

EVG (Erathem-Vanir Geological Consultants). 2010. Paleontologic Resources Analysis Letter Report for the Hermosa West Wind Farm Project (Project) in southeast Albany County, Wyoming. May 14, 2010.

Hager, M.W. 1972. A late Wisconsin-Recent vertebrate fauna from the Chimney Rock animal trap, Larimer County, Colorado. Wyoming Contributions to Geology, v. 2, p. 63-71.

Hoyt, J.H. and H. Chronic. 1962. Atokan fusulinids from the Casper Formation, east flank of the Laramie Mountains, Wyoming. Journal of Paleontology, v. 36, p. 161–164.

Jennings, J.R. 1980. Fossil plants from the Fountain Formation (Pennsylvanian) of Colorado. Journal of Paleontology, v. 54, p. 149-158.

Love, J.D. and A.C. Christiansen. 1985. Geologic map of Wyoming. U.S. Geological Survey and Wyoming Geological Survey, 1:500,000 scale.

Miller, A.K. and H.D. Thomas. 1936. The Casper Formation (Pennsylvanian) of Wyoming and its fauna. Journal of Paleontology, v. 10, p. 715–738.

Murphey, P.C. and K. Zubin-Stathopoulos. 2018. Paleontological Technical Study: Glade, Upper Galeton and Cactus Hill reservoirs and Associated Pipelines and Facilities, Northern

14 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project

Integrated Supply Project, Larimer and Weld Counties, Colorado. Paleo Solutions, Inc. PSI Report CO18LarimerERO01R, 360 p.

Pederso, S.L. 1954. A Permian (Wolfcampian) fauna of the Casper Formation of southeastern Wyoming. Journal of Paleontology, v. 28, p. 17-21.

USFS (U.S. Forest Service). 1996. Probable fossil yield classification (PFYC). Paleontology Center of Excellence and Region 2 USFS Paleo Initiative, 9 p.

Ver Ploeg, A.J. 2007. Geologic map of the Red Buttes quadrangle, Albany County, Wyoming. Wyoming State Geological Survey Map Series 76, 1:24,000 scale, 1 sheet.

Ver Ploeg, A.J. and J.F. McLaughlin. 2010. Preliminary geologic map of the Sherman Mountains West quadrangle, Albany County, Wyoming. Wyoming State Geological Survey Open- File Report 2010-3, 1:24,000 scale, 1 sheet.

Ver Ploeg, A.J., D. Bagdonas, and J.F. McLaughlin. 2011. Preliminary geologic map of the Best Ranch quadrangle, Albany County, Wyoming. Wyoming State Geological Survey Open- File Report 2011-7, 1:24,000 scale, 1 sheet.

Vietti, L. 2019. Personal communication with L Vietti, Collections Manager, University of Wyoming Department of Geology & Geophysics. December 12, 2019.

15 April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project

FIGURES

Figure 1: Geologic Map with Project Area Overlay

Figure 2: Stratigraphic Column

April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project

Figure 1: Geologic map with Project Area overlay. Geologic map units (in ascending age order): Xsv – Precambrian metasedimentary and metavolcanics; Ys – Precambrian Sherman Granite; IPPcf – Pennsylvanian- Permian Fountain and Casper Formations combined; Pfs – Permian Forelle Limestone; Qt – Pleistocene alluvial, pediment and fan deposits; Qa – Recent alluvium (from Love and Christiansen 1985).

April 2020 ConnectGen Albany County LLC Paleontological Resources Assessment Technical Report Business Confidential Rail Tie Wind Project

Figure 2 Stratigraphic column. Compiled from Ver Ploeg (2007), Ver Ploeg and McLaughlin (2010), Ver Ploeg et al. (2011) and Carnes et al. (2013).

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