
Head Instructor
Ontario Course Instructor
Bill Leedham is the President of Down 2 Earth Environmental Services Inc., and is licensed with the Association of Professional Geoscientists of Ontario (APGO) as a Professional Geoscientist (P. Geo.). Prior to establishing his own consulting firm, Mr. Leedham has worked in senior management positions for a number of environmental engineering and consulting companies.
Mr. Leedham is registered as a Qualified Person (QP-ESA) with the Ontario Ministry of Environment (MOE), for conducting Environmental Site Assessments and completing Records of Site Condition, in accordance with Ontario Regulations 153/04 and 511/09.
Mr. Leedham graduated with a Geologic Technologist Diploma from Sir Sandford Fleming College in Lindsay, Ontario. Bill is registered as a Certified Environmental Site Assessor (CESA) with AESAC; and has been teaching AESAC’s nationally accredited Phase 1 ESA Training and Certification course since 2005. Bill is continually updating and upgrading AESAC course materials; developing new training modules; and is a member of AESAC’s Certification and Ethics & Discipline committees.
Mr. Leedham has over 30 years of consulting experience in the areas of environmental site assessments, site remediation, geology, contaminant hydrogeology, geotechnical investigations and building sciences; and has conducted, managed, or peer-reviewed hundreds of ESA, remediation and risk assessment projects across Canada.
View Bill’s Website: www.down2earthenvironmental.ca

Alberta Course Instructor & Upstream Oil & Gas Specialist
Jennifer has over 20 years of experience in the environmental industry and is a Professional Agrologist (P.Ag.) through the Alberta Institute of Agrologists.
As a project manager and discipline lead, she has carried out a number of programs dealing with contamination of groundwater and soils. Jennifer is responsible for the Phase I, II and III environmental site assessments (ESA) as well as the remedial planning and implementation of contaminated sites throughout western Canada.
Jennifer’s technical areas of experience include the preparation and implementation of soil and groundwater investigations for both upstream and downstream oil and gas properties, environmental management and compliance, remedial and risk management planning, and execution. She has experience with hydrocarbon and salt contaminated soils, she has completed numerous soil survey projects relating to the development of pipelines and highways and has undertaken vegetation surveys to assess reclamation success. She has worked on numerous sites collecting groundwater samples and analyzing the data to prepare summary reports for clients and regulatory agencies. She has also dealt with spill response, remediation of sites, ex-situ treatment and disposal of soils, which included reviewing historical data and previous investigative data to delineate the extent of impacts throughout the soil. Jennifer has also been actively involved in several environmental due diligence reviews related to the acquisition and divestment of oil and gas properties which included environmental site inspections of facilities and wells sites and the development of remediation, reclamation and abandonment liability cost estimated.
Jennifer has been responsible for the organization and management of numerous environmental studies, preparation of budgets, mentorship of junior staff, as well as development and maintenance of Client relationships.

Alberta Course Instructor
Sam Siegl is the founder and principal consultant of Nexus Environmental Services Ltd., based in Lethbridge, Alberta. With over a decade of dedicated experience in the environmental consulting industry, Sam specializes in Phase I, II, and III Environmental Site Assessments for commercial and industrial properties.
 
 Sam's approach to environmental consulting is rooted in a passion for sustainability and a commitment to helping businesses navigate complex regulatory landscapes. His extensive knowledge and practical experience ensure that every project is handled with the utmost professionalism and care. Whether conducting site assessments, managing projects, or instructing AESAC courses, Sam's goal is to deliver results that not only meet but exceed expectations. 
 
 In his personal time, Sam enjoys spending time with his family and being outdoors. He is passionate about hiking, mountain biking, snowboarding, and other outdoor activities that allow him to connect with nature and stay active.
View Sam’s Website: https://www.nexusenvironmental.ca
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