Detour Lake Operation Ontario, Canada NI 43-101 Technical Report Report Prepared By: Report Prepared For: Kirkland Lake Gold Ltd. Andre Leite, P.Eng Jean-Francois Dupont, P.Eng Effective Date: Veronika Raizman, P.Geo December 31, 2020 Paul Andrew Fournier, P.Eng CERTIFICATE OF QUALIFIED PERSON I, Andre Leite, P. Eng. am employed as a Detour Lake Mine Technical Service Manager with Kirkland Lake Gold Ltd, with an address at Royal Bank Plaza, South Tower 200 Bay Street, Suite 2800 Toronto, Ontario, M5J 2J1 Canada. This certificate applies to the technical report titled “Detour Lake Operation NI 43-101 Technical Report” that has an effective date of 31 December, 2020 (the “technical report”). I am a Professional Engineer with Professional Engineers Ontario, license number 100153687; a chartered professional member of the Australasian Institute of Mining and Metallurgy (MAusIMM(CP)), member number 301888. I graduated from McGill University (Canada) in 2008 with a Master’s Degree in Mining Engineering and from Universidade Federal de Minas Gerais in 2004 with a Bachelor’s Degree in Mining Engineering. I have practiced my profession for 17 years. I have been directly involved in the mineral resource modelling for the Detour Main Pit and have reviewed in detail the mineral resource modelling for the North pit, West Detour and 58N deposits. I have also participated in life of mine planning. I have two years of experience as the Detour Lake Mine Technical Service Manager. Prior to that I held the positions of Technical Service Manager Vale Base Metals Asia Pacific, responsible for mineral resource and mineral reserve estimates for Vale Base Metal operations in the region; Principal Mine Engineer Vale Base Metals Global, leading the initiatives associated with corporate governance, technical services and technology and innovation for the Base Metals business with a major focus on their open pit operations; as mineral resource and mineral reserve specialist with the Inco (later Vale) Mineral Resources and Mineral Reserves team supporting all operations globally with mineral resource modelling, mine design, mine production planning and mineral reserve definition. As a result of my experience and qualifications, I am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (NI 43–101) for those sections of the technical report that I am responsible for preparing. I work at Detour Lake mine site, and this familiarity with the operation serves as my personal inspection. I am responsible for Sections 1.1 to 1.8, 1.10 to 1.14, 1.16, 1.18, 1.23 to 1.25; Section 2; Section 3; Section 4; Section 5; Section 6; Section 7; Section 8; Section 9; Section 10; Section 11; Section 12; Section 14; Section 15; Section 16; Section 18; Section 19; Section 23; Section 24; Sections 25.1 to 25.4, 25.6 to 25.8. 25.10, 25.12, 25.16, 25.17; Section 26, Section 27, and Appendix A of the technical report. I have been involved with the Detour Lake Mine for two years in my role as a Technical Service Manager working at site. I have read NI 43–101 and the sections of the technical report for which I am responsible have been prepared in compliance with that Instrument. As of the effective date of the technical report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading. Dated: 30 March, 2021 “Signed” Andre Leite, P.Eng. CERTIFICATE OF QUALIFIED PERSON I, Jean-Francois Dupont (P. Eng., OIQ) am employed as the Detour Lake Mine Chief Metallurgist with Kirkland Lake Gold Ltd, with an address at 1B First Avenue, Cochrane, Ontario. This certificate applies to the technical report titled “Detour Lake Operation NI 43-101 Technical Report” that has an effective date of 31 December, 2020 (the “technical report”). I am a Professional Engineer, member of L’Ordre Des Ingénieurs du Québec, license number 117145. I graduated from Laval University (Canada) in 1996 with a Bachelor’s Degree in Mining Engineering, majoring in mineral processing. I have practiced my profession for 24 years. I joined Detour Gold Corporation, a predecessor company to Kirkland Lake Gold Ltd. in 2011 and was directly involved in the engineering, construction and commissioning of the Detour Lake Mine processing plant. I have worked in the Detour Lake Mine processing plant for eight years. I have also participated in the elaboration of life-of-mine plans. Prior to that, I held various positions with Barrick Gold for 14 years including five years at the Corporate office as Comminution Metallurgist. This position gave me exposure to the 19 processing plants Barrick Gold had at the time. As a result of my experience and qualifications, I am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (NI 43–101) for those sections of the technical report that I am responsible for preparing. I am directly employed at the Detour Operation, and have been since 2011. This familiarity with the operations serves as my personal inspection for the purposes of the technical report. I am responsible for Sections 1.1, 1.2, 1.9, 1.15; Sections 2.1 to 2.6; Section 13; Section 17; Sections 25.1, 25.5, 25.9; and Section 27 of the technical report. I am not independent of Kirkland Lake Gold Ltd, as independence is described by Section 1.5 of NI 43–101. I have been involved with the Detour Operation since 2011 during engineering, construction, commissioning, and operations of the process plant. I have read NI 43–101 and the sections of the technical report for which I am responsible have been prepared in compliance with that Instrument. As of the effective date of the technical report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading. Dated: 30 March, 2021 “Signed” J-F Dupont, P. Eng (OIQ) CERTIFICATE OF QUALIFIED PERSON I, Veronika Raizman, P. Geo. am employed as a Manager for Reclamation and Geochemistry, with Kirkland Lake Gold Inc., with an address at Royal Bank Plaza, South Tower 200 Bay Street, Suite 2800 Toronto, Ontario, M5J 2J1 Canada. This certificate applies to the technical report titled “Detour Lake Operation NI 43-101 Technical Report” that has an effective date of 31 December, 2020 (the “technical report”). I am a Professional Geoscientist registered with the Professional Geoscientists of Ontario (Membership #2563). I graduated from the University of Toronto with a Ph.D. in Earth Sciences (2015), a M.Sc. in Geology (2011), and a H.B.Sc. in Environmental and Physical Geography (2010). I have practiced my profession for 10 years. Prior to joining the Detour Lake Mine in 2016, I served as a geochemist with SRK Consulting Ltd., where I gained experience in the prediction and management of acid rock drainage and metal leaching during all phases of the mining cycle, as well as mine waste characterization using static, kinetic, and field testing programs. At the Detour Lake Mine, I have previously served in multiple roles, including Environmental Specialist; Geochemistry, Research and Closure Coordinator; and Senior Advisor for Mine Closure Planning and Geochemistry. My duties have supported, but not been limited to, 1) environmental permitting, reporting and compliance, including Indigenous consultation; 2) management of geochemical monitoring programs, including water quality (i.e. effluent and receiving environment) and mine wastes (i.e. waste rock and tailings); and 3) planning and execution of progressive reclamation and mine closure activities. As a result of my experience and qualifications, I am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (NI 43–101) for those sections of the technical report that I am responsible for preparing. I have worked at Detour Lake mine site, and this familiarity with the operation serves as my personal inspection. I am responsible for Sections 1.1, 1.2, 1.17; Sections 2.1 to 2.4, 2.6; Section 20; Sections 25.1, 25.11; and Section 27 of the technical report. I was based at the Detour Lake Mine for four years and five months, followed by my current role as Manager for Reclamation and Geochemistry at the Kirkland Lake Gold Inc. Toronto corporate office, where I have served for five months. I have read NI 43–101, and the sections of the technical report for which I am responsible have been prepared in compliance with that Instrument. As of the effective date of the technical report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading. Dated: 30 March, 2021 “Signed” Veronika Raizman, P.Geo. CERTIFICATE OF QUALIFIED PERSON I, Paul Andrew Fournier, P.Eng., am employed as a Manager, Cost Accounting at the Corporate Office of Kirkland Lake Gold Ltd, with an address at Royal Bank Plaza, South Tower 200 Bay Street, Suite 2800 Toronto, Ontario, M5J 2J1, Canada. This certificate applies to the technical report titled “Detour Lake Operation NI 43-101 Technical Report” that has an effective date of 31 December, 2020 (the “technical report”). I am a Professional Engineer with Professional Engineers Ontario, license number 100218548. I graduated from McGill University (Canada) in 2011 with a Bachelor of Materials Engineering degree.