Evaluation of large-scale CO2 storage on fresh-water sections of aquifers: An example from the Texas Gulf Coast Basin

Abstract Large-scale injections of CO2 into subsurface saline aquifers have been proposed to remediate climate change related to buildup of green house gases in the atmosphere. The pressure buildup caused by such injections may impact a volume of the basin significantly larger than the CO2 plume itself. In areas with hydrological settings similar to the Gulf Coast Basin, the perturbation of the flow-field in deep parts of the basin could result in brines or brackish water being pushed up-dip into unconfined sections of the same formations or into the capture zone of fresh-water wells. The premise of the current study is that the details of multiple-phase flow processes necessary to model the near field evolution of the CO2 plume are not necessary to describe the impact of the pressure anomaly on up-dip aquifers. This paper quantitatively explores conditions under which shallow groundwater would be impacted by up-dip displacement of brines, utilizing an existing carefully calibrated flow model. Modeling an injection of water, arguably equivalent to 50 million tons of CO2/year for 50 years resulted in an average water-table rise of ∼1 m, with minor increase in stream baseflow and larger increase in ground water evapotranspiration, but no significant change in salinity.

[1]  B. Metz.  IPCC special report on carbon dioxide capture and storage , 2005 .

[2]  Christine Doughty,et al.  Modeling geologic storage of carbon dioxide: Comparison of non-hysteretic and hysteretic characteristic curves , 2006 .

[3]  Jan M. Nordbotten,et al.  Injection and Storage of CO2 in Deep Saline Aquifers: Analytical Solution for CO2 Plume Evolution During Injection , 2005 .

[4]  Michelle Bentham,et al.  CO2 Storage in Saline Aquifers , 2005 .

[5]  E. M. Winter,et al.  Disposal of carbon dioxide in aquifers in the U.S. , 1995 .

[6]  C. Neuzil.  Groundwater Flow in Low‐Permeability Environments , 1986 .

[7]  Richard H. Worden,et al.  Geological storage of carbon dioxide , 2007, Geological Society, London, Special Publications.

[8]  J. Tóth.  A Theoretical Analysis of Groundwater Flow in Small Drainage Basins , 1963 .

[9]  John Gale,et al.  Geological storage of CO2: What do we know, where are the gaps and what more needs to be done? , 2004 .

[10]  Jean-Philippe Nicot,et al.  Hydrodynamic convergence of hydropressured and geopressured zones, Central Texas, Gulf of Mexico Basin, USA , 2006 .

[11]  D. W. Peaceman.  Interpretation of well-block pressures in numerical reservoir simulation with nonsquare grid blocks and anisotropic permeability , 1983 .

[12]  L. V. D. Meer.  Investigations regarding the storage of carbon dioxide in aquifers in the Netherlands , 1992 .

[13]  Sam Holloway,et al.  Underground sequestration of carbon dioxide—a viable greenhouse gas mitigation option , 2005 .

[14]  Sam Holloway,et al.  An overview of the Joule II project ‘The underground disposal of carbon dioxide’ , 1996 .

[15]  David W. Keith,et al.  Geologic Carbon Storage: Understanding the Rules of the Underground , 2003 .

[16]  Arlen W. Harbaugh,et al.  User's documentation for MODFLOW-96, an update to the U.S. Geological Survey modular finite-difference ground-water flow model , 1996 .

[17]  C. Tsang,et al.  A method for quick assessment of CO2 storage capacity in closed and semi-closed saline formations , 2008 .

[18]  David E. Prudic,et al.  Documentation of a computer program to simulate stream-aquifer relations using a modular, finite-difference, ground-water flow model , 1989 .

[19]  W. Kinzelbach,et al.  3d-Groundwater Modeling with Pmwin: A Simulation System for Modeling Groundwater Flow and Pollution , 2001 .

[20]  Sally M. Benson,et al.  Geologic storage of carbon dioxide as a climate change mitigation strategy: performance requirements and the implications of surface seepage , 2005 .

[21]  Sally M. Benson,et al.  The impact of geological heterogeneity on CO2 storage in brine formations: a case study from the Texas Gulf Coast , 2004, Geological Society, London, Special Publications.

[22]  Keni Zhang,et al.  Research project on CO2 geological storage and groundwaterresources: Large-scale hydrological evaluation and modeling of impact ongroundwater systems , 2008 .