Summary:

Underground pipeline leakage which results in gas buildup and migration though soil and ultimately its release into the air or a substructure (e.g. basement) can be catastrophic. What is not well understood in underground pipeline leakage scenarios is how the environmental conditions affect the gas migration behavior. However, if we can better predict the conditions that cause gas migration and how to account for such factors in our decision making, we can more efficiently and safely respond to such leaks and ultimately help prevent the occurrence of gas migration incidents. This project will:

1. Develop an analytic method to predict the conditions needed for gas migration to occur.
2. Establish a recommended practice to improve response to gas migration incidents, specifically addressing how to work with states to improve the efficiency of finding and fixing gas leaks.

This work will be accomplished by a combined team of University of Texas at Arlington, Colorado School of Mines, Colorado State University, state agencies and industry partners, including pipeline operators, service providers and surveyors. 

Objectives:

The proposed work directly addresses the request to develop an analytic method to predict the environmental conditions needed for gas migration to occur and will also:

• Provide recommendations on improving response to gas migration incidents.
• Develop guidance on parameters affecting gas migration that can be applied to the field.
• Provide recommendations on how to work with the states, specifically the state of Colorado, on a program to improve the ability to find and fix such gas leaks.

Project outputs:

Ulrich, B.A., M. Mitton, E. Lachenmeyer, A. Hecobian, D. Zimmerle, K.M. Smits. 2019. Natural gas emission from underground pipelines and implications for leak detection. Env. Sci. Tech. Lett., https://doi.org/10.1021/acs.estlett.9b00291

Cho, Y., B. Ulrich, D. Zimmerle, K.M.Smits, Novel dimensionless surface concentration number approach for estimation of leak rates from underground natural gas pipelines, Env. Pollution, https://doi.org/10.1016/j.envpol.2020.115514.