Environmental Effects Assessment of Oil and Gas Development on a Grassland Ecosystem A Thesis Submitted to the College of Graduate Studies and Research in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Department of Geography and Planning, University of Saskatchewan, Saskatoon By Lawrence Christopher Nasen © Copyright Lawrence C. Nasen, December 2009 All rights reserved PERMISSION TO USE In presenting this thesis in partial fulfillment of the requirements for a Postgraduate degree from the University of Saskatchewan, I agree that the Libraries of this University may make it freely available for inspection. I further agree that permission for copying of this thesis in any manner, in whole or in part, for scholarly purpose may be granted by the professor or professors who supervised my thesis work, or in their absence, by the Head of the Department or the Dean of the College in which my thesis work was done. It is understood that any copying or publication or use of this thesis or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Saskatchewan in any scholarly use which may be made of any materials in my thesis. Requests for permission to copy or to make use of material in this thesis in whole or part should be addressed to: Head of the Department of Geography and Planning University of Saskatchewan Saskatoon, Saskatchewan, S7N 5A5 i ABSTRACT The northern Great Plains of Saskatchewan is one of the most significantly modified landscapes in Canada. While the majority of anthropogenic disturbance to Saskatchewan‘s grasslands is the result of agricultural practices, oil and gas activity are of increasing concern to grassland conservation efforts. Although such developments require formal regulatory approval (Environmental Impact Assessment), follow-up and monitoring of the effects of oil and gas development on grasslands is not common practice. In the absence of empirical based follow-up and monitoring, the actual environmental effects of petroleum and natural gas (PNG) development on grassland ecology and the spatial extent of development are largely unknown. This thesis examines the spatial and temporal extent of PNG development and its effects on grassland ecology within a PFRA (Prairie Farm Rehabilitation Administration) pasture in southwest Saskatchewan. The extent of the changes to infrastructure and the actual impacts from development within the study area were documented from 1955 to 2006. The actual impacts of oil and gas activity on grassland ecology were determined by analyzing ground cover characteristics, soil properties, and community composition at lease sites and compared to reference pasture sites. Associated with construction practices, lease sites had low herbaceous, Lycopodiaceae, litter, organic horizon (Ah) thickness, and soil compaction values. Lease sites were also found to have low desirable species diversity, range health values, and greater undesirable species presence. Impacts from development were amplified at active, highly productive lease sites. The impacts associated with PNG development were also found to persist for more than 50 years, and extend 20m – 25m beyond the physical footprint of infrastructure. This research will contribute to monitoring and mitigation measures for oil and gas development within Saskatchewan and Canadian grasslands. ii ACKNOWLEDGEMENTS I am tremendously grateful for the encouragement, support, and patience provided to me by my supervisor Dr. Bram Noble. My sincere thanks go to my research committee, Dr. O.W. Archibold and Dr. Jill Johnstone, whose guidance and suggestions improved the content of this thesis. I would also like to thank Dr. Eric Lamb for his contributions as an external examiner. Funding, field equipment, and site access were provided by the Prairie Farm Rehabilitation Administration (PFRA-AAFC). Special thanks to everyone in the Range and Biodiversity Division of the PFRA, especially Brant Kirychuk for the opportunity to conduct the research and Bret Ward who provided logistical support and encouragement during my program. Special consideration is also given to Swift Current-Webb community pasture manager Kelly Ashdown and Tara Mulhern Davidson for their knowledge and insight. Funding was also provided from the Department of Geography and Planning at the University of Saskatchewan. I am especially thankful to my family, Theresa, Ray, and James, whose continuous love, support, optimism, and encouragement have helped me more than they know. The thesis is dedicated to the memories of my grandparents, Maureen and John Lomax, and Marry and Kurt Nasen. Special thanks to the faculty, staff, and fellow graduate students in the Department of Geography and Planning, Biology, and Toxicology, and all the people I met throughout Saskatchewan who made my time here so enjoyable. iii TABLE OF CONTENTS Permission To Use Abstract i Acknowledgements ii Table of Contents iii List of Tables vi List of Figures viii List of Acronyms ix 1.0 INTRODUCTION 1 1.1 Purpose and Objectives 4 1.2 Thesis Organization 6 2.0 OIL AND GAS DEVELOPMENT IN SASKATCHEWAN AND POST-DECISION EFFECTS ASSESSMENT 7 2.1 Introduction 7 2.2 The Great Plains of Saskatchewan, Canada 7 2.3 Oil and Gas Development in Saskatchewan 11 2.4 Oil and Gas Regulatory Processes and Environmental Impact Assessment 13 2.5 Post-decision Effects Assessment of Oil and Gas Development on Grasslands 15 2.5.1 Follow-up practice 16 2.6 Conclusion 20 3.0 RESEARCH METHODS AND ANALYTICAL TOOLS 22 3.1 Introduction 22 3.2 Study Area: Swift Current-Webb Community Pasture 23 3.2.1 PFRA objectives and land management 27 3.3 Data Collection and Analysis 28 3.3.1 Aerial photo and secondary source data 29 3.3.2 Field data collection and analysis 30 3.3.2.1 Sampling site selection 30 3.3.2.2 Field sampling design 31 3.3.2.3 Field data collection 33 3.3.2.4 Pre-analysis data screening and transformations 35 3.3.2.5 Multi-Response Permutation Procedure (MRPP) 37 3.3.2.6 Non-Metric Multidimensional Scaling (NMDS) 38 3.3.2.7 Indicator species analysis 40 3.3.2.8 Calculating spatial extent of ecological effects 40 iv 4.0 RESULTS 42 4.1 Introduction 42 4.2 Spatial and Temporal Development of Oil and Gas in the Swift Current-Webb Community Pasture 42 4.2.1 Physical footprint of oil and gas infrastructure 43 4.3 The Effects of Oil and Gas Lease Sites on Grassland Ecology 51 4.3.1 Comparing lease sites to off-lease sites 51 4.3.2 Relationship between well drill year and lease class, and the impacts to grassland ecology 54 4.3.3 Well production and abiotic and biotic conditions 60 4.3.4 Abiotic and biotic conditions at increasing distance from the well head 64 4.3.5 Spatial extent of oil and gas well sites impacts on grassland ecology 72 5.0 DISCUSSION AND CONCLUSIONS 75 5.1 Introduction 75 5.2 Spatial and Temporal Development of PNG Activity in Southwest Saskatchewan 75 5.3 Impacts of PNG Lease Sites on Mixed Grassland Ecosystems 78 5.4 The Role of PNG Productivity, Infrastructure Type, and Year Drilled 81 5.5 Spatial Extent of the PNG Impacts to Grassland Ecosystems 83 5.6 Implications for EIA Follow-up Programs and Grassland Management 86 5.7 Conclusion 88 LITERATURE CITED 92 APPENDIX 98 v LIST OF TABLES Table 2.1 Provincial regulatory requirements for the disposition of oil and gas development.…………..14 Table 2.2 Basic steps of the Canadian EIA process………………………..……………………………..17 Table 2.3 Components of the EIA follow-up process…………………………………………………….18 Table 4.1 Oil and gas infrastructure in Swift Current-Webb Community Pasture, 1955 – 2005……...…44 Table 4.2 Percent loss and fragmentation statistics associated with PNG infrastructure in 1979………...50 Table 4.3 Percent loss and fragmentation statistics associated with PNG infrastructure in 1997………...50 Table 4.4 Percent loss and fragmentation statistics associated with PNG infrastructure in 2005………...50 Table 4.5 Results from the MRPP analysis comparing PNG lease sites to the reference pasture…………………………………………………………………………………………51 Table 4.6 Median values + standard deviation and t-tests for ground cover, and physical and chemical soil variables at lease sites and reference pastures……………………………….…52 Table 4.7 Indicator species analysis (IV %) of undesirable species for PNG lease sites and reference sites………………………………………………………………………………….54 Table 4.8 Axis correlation scores for axis 1 and axis 2 for the NMDS ordination analysis of 121 transects plotted in ground cover variables and range health space with lease class group overlay….…………………………………………………………………………...….56 Table 4.9 MRPP analyses of how PNG lease operational statuses differ based on measures of desirable and undesirable species alpha diversity measures……………………………..…….57 Table 4.10 Desirable and undesirable species diversity, richness, and range health for each PNG infrastructure type…………………………………………………………………57 Table 4.11 Indicator analysis of desirable species at reference pasture sites…………………………..…58 Table 4.12 MRPP analyses of ground cover, soil, and plant community data with cumulative well site production………..…………………………………………………………………61 Table 4.13 Axis correlation scores for axis 1 and axis 3 for the NMDS ordination analysis of 121 lease site transects plotted in ground cover and lease site production data………….....….…62 Table 4.14 Correlation coefficients from the NMDS ordination analysis of ground cover and soil properties for the thirty one oil and gas lease sites plotted in production