Induced Seismicity Traffic Light Protocol at the Alberta No. 1 Geothermal Project Site

Type:

Research Report

Link:

https://www.sciencedirect.com/science/article/pii/S0375650523002158

Authors:

Ali Yaghoubi - PhD student, Earth and Environmental Sciences, University of Waterloo
Ryan Schultz - Scientific Assistant, Swiss Seismological Service, ETH Zürich, Zürich, Switzerland
Dr. Catherine Hickson - C.E.O., Alberta No. 1; Chief Geologist, Terrapin Geothermics
Andrew Wigston - Geologist (Natural Resources, CanmetENERGY), Government of Canada
Dr. Maurice B. Dusseault - Professor, Engineering Geology, University of Waterloo

Citation:

Yaghoubi, A., Schultz, R., Hickson, C., Wigston, A., Dusseault, M.B., Induced seismicity traffic light protocol at the Alberta No. 1 geothermal project site, Geothermics, Volume 117, 2024, 102860, ISSN 0375-6505, https://doi.org/10.1016/j.geothermics.2023.102860.

Abstract:

The Alberta No. 1 Geothermal Project (ABNo1) is a renewable energy project in Canada; it will use deep geothermal energy for electrical power generation and direct-use thermal power. However, concerns regarding induced seismicity must be addressed. This study proposes implementing the Traffic Light Protocol (TLP) as a risk management tool for conventional geothermal projects in Alberta. We focus on determining an appropriate TLP red-light threshold, employing a risk-informed approach for the Leduc Formation - one of the geothermal reservoirs proposed for development by ABNo.1. The recommended red-light threshold of ML 3.5 signifies the level at which operations must be halted (i.e., the red light) to mitigate nuisance impact, damage, and personal risk. The recommended yellow light threshold of ML 1.5 signifies the level at which assessment of injection operations must be re-assessed, the regulator must be informed, and a risk mitigation analysis must be undertaken to re-evaluate operations to keep induced seismicity at a low magnitude. Comparison to induced seismicity near the project site highlights key factors requiring consideration during the project’s design phase: injection volume, chances of basement fault reactivation, and delayed seismic activity onset. Effective mitigation entails controlling injection rate, continuous fluid balance monitoring, allowing gradual and appropriate pressure dissipation rates, and potentially the use of tracer tests to deconvolve pathways. This study provides insights for stakeholders involved in injection projects, aiding risk mitigation and ensuring safe, sustainable energy extraction while also prioritizing the local community’s well-being.

Acknowledgment:

The authors thank geoLOGIC systems ltd. for their contribution of geoSCOUT™ data and software used in this study. The Alberta No. 1 project is partially funded through a grant from Natural Resources Canada’s Emerging Renewable Power Program.

Keywords:

Alberta No. 1 geothermal project (ABNo1), Traffic light protocol (TLP), Geothermal energy, Induced seismicity, Risk management, Subsurface geothermal resources, Hydraulic fracturing (HF), Hydraulic stimulation, Leduc Formation, Renewable energy