Environmental Assessment of the Subsurface
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Oregon Caves National Monument Subsurface Management Plan – Environmental Assessment National Park Service U.S. Department of the Interior Oregon Caves National Monument 19000 Caves Highway Cave Junction, Oregon 97523 Document Prepared by: John Roth Natural Resources Specialist Oregon Caves National Monument Compilation date: September, 2005 Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 1 This page intentionally left blank Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 2 Environmental Assessment of Subsurface Management Plan Summary This document is an environmental assessment (EA) of Oregon Caves National Monument’s draft subsurface management plan which is attached to this document as an appendix. The plan provides National Park Service (NPS) management with the necessary framework to guide subsurface management within the Monument for the next 15 years. The plan is intended to be a useful long-term decision-making tool, providing NPS managers with a logical and trackable rationale for decisions about the protection and public use of the Monument’s subsurface resources. Since the Monument’s enabling legislation was intended primarily to protect a showcave called Oregon Caves (hereinafter referred as the Caves) and, by implication, about 6 other, much smaller caves within the Monument, it is imperative that an environmental assessment of the Monument’s subsurface be done in order to determine whether a Finding of No Significant Impact (FONSI) or an Environmental Impact Statement (EIS) is warranted. At the beginning of the planning process for this assessment, a series of federal manager and public scoping meetings were held and letters sent to interested parties to present the purpose and need for an environmental assessment of the Monument’s subsurface plan, to present the purpose and significance of the Monument to the public, to outline Monument mission goals, and to present issues that will be addressed in the plan. Input was solicited from the public and other governmental agencies to discern if there were other issues that needed to be addressed in the plan which were not initially listed. Among the issues brought up during the public scoping process was the need for more studies of cave processes, the need for greater protection of cave processes and other cave resources, and the need for more experienced cave managers and interpreters. In response to these issues, and cognizant of the mission goals established for the Monument, this subsurface management plan EA emphasizes the ratio of studies versus other subsurface management actions and subsurface management versus surface management projects and actions by providing five alternative approaches for the protection, public use, and management of Monument subsurface resources. The following alternatives were developed: Alternative A is the “No Action Alternative.” Alternative A would involve a continuation of existing conditions, including about an equal emphasis on subsurface management compared to the rest of resource management in the Monument but would only involve research and other actions that involve public tours on paved trails. Alternative B constitutes the preferred alternative. Alternative B would increase the emphasis on subsurface management but would balance the emphasis on subsurface research and non-research actions. Baseline and monitoring studies would continue to occur, such as new photos at photo-monitoring points, water and air quality sampling, and monitoring of changeable attributes of a room-by-room inventory. Monitoring would also evaluate ongoing restoration and mitigation. Actions would include subsurface restoration and mitigation, training of park staff, inventory and monitoring based on the vital signs and park cluster concepts, and offering public tours that would vary in both time and distance covered both on and off the Caves’ paved trail. Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 3 Cave restoration would include removing rubble, lint, tracked in dirt, non-historic infrastructure, and non- paved trails, installing tarps or cement ridges to trap human-caused particulates, controlling non-native species, repairing cave formations, installing emergency toilets, and altering entrances or passages so that their cross-sectional areas are similar to what existed prior to the historic discovery of the Caves. Alternative B is considered the environmentally preferred alternative. Alternative C would decrease the emphasis on subsurface management. The emphasis would be on surface management and subsurface management would be about evenly split between research and non- research actions. Alternative D would increase the emphasis on baseline and monitoring studies. Alternative E would decrease the emphasis placed on baseline and monitoring studies. Major actions would include subsurface restoration, mitigation and prevention of human impacts. These alternatives and the draft subsurface management plan are presented to the public in order to receive input in regards to the public’s choice of alternatives, the addition of subject matter expertise, and in making both the subsurface management plan and this document more effective, factual, understandable, and transparent. Actions common to all alternatives include implementation of previous relevant environmental assessments and environmental impact statements, protection of the Oregon Caves Historic District, ongoing consultation with both cavers and non-cavers with subject matter expertise, and regional cooperation on various issues such as fire management, surface edge and fragmentation effects, and the effects of tourism. Acronyms and other abbreviations in this document are spelled out initially and include: Caves………Monument’s main cave and its only showcave CFR………..Code of Federal Regulations EIS…………Environmental Impact Statement FCRPA….…Federal Cave Resources Protection Act DOI………...Department of Interior EIS………....Environmental Impact Statement GMP……….General Management Plan Monument….Oregon Caves National Monument NHPA……...National Historic Preservation Act NEPA……...National Environmental Preservation Act NPS..………National Park Service RMP……….Resource Management Plan U.S.C………United States Code USDA……..United States Department of Agriculture Several text changes, corrections and additions were made throughout revisions of this document, Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 4 including the Purpose and Need, Affected Environment, and Environmental Consequences chapters of the document, as a result of input from the public and government agencies. A summary chart of actions for each alternative is included in the document. Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 5 TABLE OF CONTENTS CHAPTER 1 – PURPOSE AND NEED 1.1 BACKGROUND 1.2 PURPOSE AND NEED FOR FEDERAL ACTION 1.3 AUTHORITIES AND GUIDELINES 1.4 ISSUES AND IMPACT TOPICS 1.5 TOPICS DISMISSED FROM FURTHER CONSIDERATION CHAPTER 2 – DESCRIPTION OF ALTERNATIVES 2.1 ALTERNATIVE A – No Action 2.2 ALTERNATIVE B (Preferred Alternative) – Increase Emphasis on Subsurface Management, but Balance the Emphasis on Subsurface Research and Non-Research Actions. 2.3 ALTERNATIVE C – Decrease Emphasis on Subsurface Management 2.4 ALTERNATIVE D – Increase Emphasis on Baseline and Monitoring Studies. 2.5 ALTERNATIVE E - Decrease Emphasis Placed on Baseline and Monitoring Studies; Major Actions Would Include Subsurface Restoration, Mitigation and Prevention of Human Impacts. 2.6 MITIGATING MEASURES UNDER ALL ALTERNATIVES 2.7 ALTERNATIVES CONSIDERED BUT REJECTED Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 6 2.8 ENVIRONMENTALLY PREFERRED ALTERNATIVE CHAPTER 3 – AFFECTED ENVIRONMENT 3.1 SUMMARY 3.2 GEOLOGY 3.3.1 Bedrock 3.3.2 Speleogenesis 3.3.3 Cave formations 3.3 CAVE CLIMATE 3.3.1 Airflow 3.3.2 Carbon Dioxide 3.3.1 Radon 3.4 SUBSURFACE HYDROLOGY 3.5 SUBSURFACE BIOLOGY 3.5.1 Species Summary 3.5.2 Bats 3.5.3 Rare Habitats 3.5.3 Species of Special Concern 3.5.4 Fossils 3.5.5 Microbes 3.5 CULTURAL RESOURCES 3.6.1 Overview 3.6.2 Archeology 3.6.3 Historical 3.6.4 Visitor Use and Experience 3.6 HUMAN IMPACTS CHAPTER 4 – IMPACTS OF ALTERNATIVES CHAPTER 5 – CONSULTATION AND COORDINATION BIBLIOGRAPHY GLOSSARY Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 7 APPENDIX A: DRAFT SUBSURFACE MANAGEMENT PLAN Environmental Assessment of Cave Management Plan – Oregon Caves National Monument 8 CHAPTER 1 – PURPOSE AND NEED 1. 1 BACKGROUND The Caves were discovered in 1874 by a Euro-American hunter. In 1907, four sections of land, encompassing approximately 2,560 acres were withdrawn from the operation of the public land laws of the United States, apparently for the purposes of establishing the Monument. Two years later, a 480 acre Monument was established by proclamation of President William H. Taft. The proclamation was intended primarily to protect the showcave on the Monument Oregon Caves (hereinafter referred as the Caves) and, by implication, about 6 other, much smaller caves within the Monument. The U.S. Forest Service began the first guided cave tours at Oregon Caves in 1911. It was one of the first uses of federal interpreters in what would later become a NPS area in 1934. In 1922 a private concession took over the guiding of the cave tours. The 1998 Oregon Caves National Monument General Management Plan/Environmental