John Avis is the President of Geofirma with over 30 years experience in a wide variety of technical areas related to environmental site assessment and radioactive waste disposal. He leads the firm’s numeric modelling practice and is a registered Professional Engineer in the Province of Ontario. In the area of radioactive waste management, John has led teams responsible for evaluation of remediation alternatives at historic waste management sites and has performed detailed flow and transport modelling in support of safety assessments of proposed deep geological repositories.

In the latter role, John has directed and performed groundwater flow, solute transport, and gas transport modelling to assess facility performance over a million-year period and has led modelling work to better understand the dynamics of a deep stagnant flow system and the impact on it of glacial advance and retreat.

John is an expert in the design, implementation, and analysis of hydraulic testing programs for the hydrogeological characterization of deep bedrock flow systems, and recently managed the hydraulic testing program in two boreholes at a site near Teeswater, ON.  Over 40 hydraulic tests were conducted at depth up to 900 m, using 30m and 5m straddles.

John also has strong skills in software development and developed a well test simulator (nSights), model pre-and post-processor (mView), and stochastic framework (paCalc) for assessing risk and contaminant mass flux associated with contaminant sources. This software was developed for international radioactive waste management programs (e.g. the U.S. Department of Energy program at Yucca Mountain) and is in use around the world (e.g., domestic and U.S. programs, Nagra, SKB, ANDRA, and JNC).