University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2017 Tracing Sources of Nitrate in Rivers of Southern Alberta Using Nitrogen, Oxygen, and Boron Isotopes as Co-Tracers Kruk, Mary Krystin Kruk, M. K. (2017). Tracing Sources of Nitrate in Rivers of Southern Alberta Using Nitrogen, Oxygen, and Boron Isotopes as Co-Tracers (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/28495 http://hdl.handle.net/11023/3699 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Tracing Sources of Nitrate in Rivers of Southern Alberta Using Nitrogen, Oxygen, and Boron Isotopes as Co-Tracers by Mary Krystin Kruk A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE GRADUATE PROGRAM IN GEOLOGY AND GEOPHYSICS CALGARY, ALBERTA APRIL, 2017 © Mary Krystin Kruk 2017 Abstract The natural and anthropogenic sources of nitrate (NO3) in the Bow River, Oldman River, and select tributaries of the Oldman River (OMR) in southern Alberta were determined by analyzing 15 18 11 a combination of δ NNO3, δ ONO3 and δ B values in surface water samples and in 15 18 11 anthropogenic nutrient end-members. The δ NNO3, δ ONO3 and δ B values of surface water revealed Bonnybrook WWTP effluent has the greatest influx of nutrient load to the Bow River and downstream of Calgary agricultural return flow water is an additional source of nutrients. Decreasing NO3 loads and NO3/B ratios downstream of Calgary indicated that there are also N- 15 11 removal processes occurring in this reach. The δ NNO3 and δ B values of the surface water in the OMR indicated a significant nutrient input by the Lethbridge WWTP effluent and tributaries displayed δ11B values heavily indicative of cow manure. Hence, boron isotopes are a useful co- tracer of nutrients in surface water. ii Acknowledgements I would like to thank my supervisor, Dr. Bernhard Mayer, for all the teaching, knowledge and guidance he provided during the course of this research project. I am truly grateful for all that I have learned through him and the spirit of independent research that he instilled. I am also thankful for the financial support of my project through the NSERC Discovery Grant. To Mike Nightingale, I cannot express how thankful I am for all the hours of scientific discussion, the assistance in the geochemistry lab, and the light conversation provided when things were going awry in my lab work, it was a pleasure. Thank you to Maurice Shevalier with all of the logistical and technical support provided during my project, things would never have run as smoothly without this. Thank you to the staff in the Isotope Science Laboratory: Steve Taylor, Andrew Kingston, Jesusa Pontoy, Niloufar Nadari and to Kerri Miller for all the assistance with my isotopic analyses and to Farzin Malekani for assistance with chemical analyses. Thanks to Dr. Michael Wieser for use of his laboratory and insight to my boron isotopic analyses. To all of the students and research associates in the Applied Geochemistry Group, and to my friends from other research groups, I cannot express how thankful I am to have worked with you and to and built friendships with you. This truly shaped my graduate school experience and left a lasting impression on me. I am grateful for everything from getting assistance outside my area of knowledge, to coffee breaks, to lunch club, to rock climbing/skiing/hiking/swimming breaks, they were all much needed and I enjoyed every minute. iii To Veronique, Nadine, Jess, Christine, Friderike, Carmen and Paul who all assisted me with my field work, thank you so much for the help and the company. Veronique, thank you for being my fellow Bond Girl in trips to the Wastewater Treatment Plants. Thank you to Susan Dooley and to all of those who work in the Department of Geoscience main office for providing such efficient administrative support during my project. Thank you to Dr. Benjamin Ellert from Agriculture and Agri-Food Canada for providing me with agricultural samples and the supplementary information, and to the research associates from INRA and BRGM in France who provided insight to my boron ion exchange experiment. Finally, I need to thank my family and friends who have given me life-long love and support, and to Paul who has only provided patience and encouragement during the ups and downs of my project. iv Table of Contents Abstract .............................................................................................................................. ii Acknowledgements .......................................................................................................... iii Table of Contents ...............................................................................................................v List of Tables .................................................................................................................. viii List of Figures ................................................................................................................... xi Introduction ...............................................................................................1 1.1 PROJECT RATIONALE ...............................................................................................1 1.2 INTRODUCTION TO ISOTOPE TRACING OF NO3 .................................................5 1.2.1 δ15N and δ18O of Nitrate .........................................................................................5 1.2.2 δ11B as a Tracer of Nutrient Sources ....................................................................11 1.3 RESEARCH OBJECTIVES ........................................................................................18 Study Area ...............................................................................................19 2.1 INTRODUCTION .......................................................................................................19 2.1.1 Climate and Hydrology of Southern Alberta ........................................................23 2.1.2 Geology .................................................................................................................24 2.1.3 Soil Types .............................................................................................................25 2.1.4 Water and Land Use .............................................................................................26 2.2 WASTEWATER TREATMENT PLANT PROCESSES ...........................................29 2.2.1 Pre-Treatment .......................................................................................................30 2.2.2 Primary Treatment & Clarifiers ............................................................................31 2.2.3 Secondary Treatment & Clarifiers ........................................................................31 2.2.4 Tertiary/Advanced Treatment ...............................................................................32 2.3 MANURE AND FERTILIZER ...................................................................................32 Sampling and Analytical Methods ......................................................35 3.1 FIELDWORK ..............................................................................................................35 3.1.1 Overview ...............................................................................................................35 3.1.2 Surface Water Sampling Sites ..............................................................................37 3.1.3 Wastewater Treatment Plant Effluent Samples ....................................................41 3.1.4 Surface Water Sample Collection & Preparation .................................................41 3.2 LABORATORY ANALYSES ....................................................................................42 v 3.2.1 Physical and Chemical Data .................................................................................42 3.2.2 Solid Sample Preparation ......................................................................................43 3.2.3 Boron Ion Exchange .............................................................................................46 3.2.4 Isotope Ratios .......................................................................................................51 Discharge and Water Sources of Southern Alberta Rivers ...............57 4.1 DISCHARGE DATA...................................................................................................57 4.1.1 Introduction ...........................................................................................................57 4.1.2 River Discharge Data ............................................................................................57 4.2 d2H AND d18O OF WATER .......................................................................................62 4.2.1 Introduction ...........................................................................................................62 4.2.2 Results ...................................................................................................................64