Characterization of the Physical and Hydraulic Properties of Peat Impacted by a Temporary Access Road by Jenna K. Pilon A thesis presented to the University of Waterloo in fulfillment of the thesis requirement for the degree of Master of Science in Geography Waterloo, Ontario, Canada, 2015 © Jenna K. Pilon 2015 Author’s Declaration I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. ii Abstract Due to the disruption of hydrology and water quality, permanent installation of roads and well pads is a practice that is discouraged. It is becoming more common to install temporary structures, which can subsequently be removed. However, little is known regarding the temporary or permanent hydrologic and biogeochemical impacts of temporary structures. In 2013, a temporary Access Road (at Pad 106) within the Firebag Fen in northeast Alberta was reclaimed to evaluate immediate and longer-term hydrologic and biogeochemical responses within the fen. Prior to its removal, the road hindered the natural water flow, and the restriction of runoff by the road led to vegetation mortality on the up- gradient (wet) side of the road. The long-term goal of the Suncor Firebag Road Removal Reclamation Project was to determine the capacity of the affected fen to naturally self-correct and self-regulate following road removal before intervention attempts. The specific objectives of this thesis are to: (1) compare peat physical characteristics and hydraulic conductivity in disturbed peat and undisturbed peat; and (2) determine the rate of change in water table and hydraulic gradients on both sides of the road immediately following road removal. Coring locations and groundwater well sites were located along transects running perpendicular to the road and, once the road was removed, on the peat that was underneath the road. Cores were collected for the determination of peat physical characteristics. Groundwater wells were installed for the determination of water table position and hydraulic gradients. Meteorologic conditions were monitored with a on-site station at the Firebag Fen site and showed variability between monitoring stations, and across the road, but consistently over time. Results indicate that the direction of flow was diagonal to the road. Heads decreased from the east (566.01 m.a.s.l mean) to the west (565.33 m.a.s.l mean) over 179 m and from Transect 1 (565.54 m.a.s.l mean) to Transect 4 (565.86 m.a.s.l mean) over 182 m. Median saturated hydraulic conductivity determined from laboratory measurments did not vary between the road and adjacent peatlands (10-3 – 10-2 m/s). Significant differences between the road and adjacent peatlands were not found for saturated hydraulic conductivity (p < 0.05). Porosity, bulk density, and specific yield varied significantly (p < 0.05) between peat on the east side of the road and the peat beneath the removed road. Porosity and bulk density also iii differed significantly between the east and west sides of the road (p < 0.05). Immediately following road removal, peat subsidence beneath the road was apparent. However, as the summer 2013 field season progressed, measured rates of peat subsidence began to slow 45 days post road removal, suggesting that the peat may have begun to rebound. iv Acknowledgements There are a number of people without whom this thesis might not have been written, and to whom I am greatly indebted. I want to thank my supervisors, Richard Petrone and Merrin Macrae. I am very appreciative of your support and guidance. Thanks also to Jonathan Price and Mike Stone for serving as members of my Examining Committee. I am very thankful for all the help I received during fieldwork while working on the project with Suncor Energy at Firebag Village Camp in the summer of 2013. A huge thank you goes out to Corey Vogel, Chuck Symons, Jon Downs, Matt Billadeau, Zac Moody, Kyle Seipert and Lyle Seipert. The University of Waterloo Meteorology Research lab also deserves thanks: Jonathan Price, George Sutherland, James Sherwood, Scott Brown, Alex MacLean, Corey Wells, Vito Lam, Adam Green and Tristan Gingras-Hill. Thank you for your assistance on this project. I would like to acknowledge James McCarthy for his ongoing advice and assistance with GIS: thank you! A huge word of thanks also goes out to Adam Lentz, Thomas Pertassek, Tobias KD Weber, and Richard Elgood; thank you for your help and support! I am specifically grateful for Terry Osko’s insightful advice. Your generous feedback and positivity made this project possible! A HUGE thank you goes out to my mom and dad for their encouragement, love and support throughout all my school years. Thank you for everything! v Dedication For my parents. “As we express our gratitude, we must never forget that the highest appreciation is not to utter words, but to live by them.” ~John F. Kennedy ♥ vi Table of Contents Author’s Declaration .............................................................................................................. ii Abstract................................................................................................................................... iii Acknowledgements ................................................................................................................. v Dedication ............................................................................................................................... vi Table of Contents .................................................................................................................. vii List of Figures......................................................................................................................... ix List of Tables ........................................................................................................................... x List of Appendices .................................................................................................................. xi 1.0 Introduction ....................................................................................................................... 1 1.1 Literature Review ......................................................................................................... 3 1.1.1 Western Boreal Forest and Athabasca Oil Sands Region ........................................ 3 1.1.2 Peatland Ecohydrology ............................................................................................ 5 1.1.3 Physical Hydraulic Properties .................................................................................. 7 1.1.3.1 Porosity ............................................................................................................. 8 1.1.3.2 Specific Yield.................................................................................................... 9 1.1.3.3 Bulk Density ..................................................................................................... 9 1.1.3.4 Soil Moisture Retention .................................................................................. 11 1.1.3.5 Hydraulic Conductivity................................................................................... 12 1.1.3.6 Peat Subsidence............................................................................................... 13 1.1.3.7 Peat Anisotropy............................................................................................... 16 1.1.4 Road Effects and Restoration................................................................................. 17 2.0 Site Description ............................................................................................................... 19 2.1 Athabasca Oil Sands Region ...................................................................................... 19 2.2 Firebag Site .................................................................................................................. 22 3.0 Methods............................................................................................................................ 27 3.1 Field Instrumentation ................................................................................................. 27 3.1.1 In Situ Hydrometric Variables ............................................................................... 27 3.1.2 Field Measurement of Peat Subsidence and Survey of Vegetation Cover ............ 28 3.1.3 Collection of Peat Samples for Laboratory Analyses of Peat Physical Parameters ......................................................................................................................................... 28 3.2 Laboratory Analyses of Peat Physical Parameters .................................................. 29 3.2.1 UMS HYPROP System ......................................................................................... 30 3.2.1.1 UMS HYPROP Experimental Design and Set-up .............................................. 32 3.2.2 Laboratory Measurements of Saturated Hydraulic Conductivity (KSAT) ............ 38 3.2.3 Measurement and Testing of Physical Parameters ................................................ 39 vii 3.2.4 Manipulation of Water Level Measurements ........................................................ 43 3.2.5 Calculation of Volumetric Flow ............................................................................ 45