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Geologic carbon sequestration injection wells in overpressured storage reservoirs: estimating area of review
Author(s) -
Oldenburg Curtis M.,
Cihan Abdullah,
Zhou Quanlin,
Fairweather Stacey,
Spangler Lee H.
Publication year - 2016
Publication title -
greenhouse gases: science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.45
H-Index - 32
ISSN - 2152-3878
DOI - 10.1002/ghg.1607
Subject(s) - cabin pressurization , aquifer , injection well , petroleum engineering , geology , water well , leakage (economics) , carbon sequestration , environmental science , water injection (oil production) , groundwater , overpressure , hydrology (agriculture) , geotechnical engineering , carbon dioxide , materials science , chemistry , organic chemistry , economics , macroeconomics , physics , composite material , thermodynamics
Abstract The Area of Review (AoR) under the US Environmental Protection Agency's (EPA) Class VI CO 2 injection permit is defined as the region surrounding the geologic carbon sequestration (GCS) project where underground sources of drinking water (USDWs) may be endangered. Estimation of the AoR is based on the calculated reservoir pressurization due to CO 2 injection and the associated potential to lift saline water into potable groundwater aquifers through open flow paths (e.g. wells) assuming the system is hydrostatic. In cases where the storage reservoirs are not initially hydrostatic, and in particular where they are overpressured, AoR estimation methods need to be altered. In this paper, we present and apply an approach to evaluating potential endangerment of USDW based on comparing brine leakage through a hypothetical open flow path in a no‐injection scenario and brine leakage in a CO 2 ‐injection scenario. We present six possible ways to normalize injection‐related leakage relative to no‐injection leakage. We calculate leakage using semi‐analytical solutions for single‐phase flow and model reservoir pressurization and flow up (single) leaky wells located progressively farther from the injection well. For an example case of relative overpressure and using an injection‐rate‐based approach, results show 50‒60% larger open‐well‐leakage rates for wells located at 2 km and 10% increase for wells located at 10 km from the injection well relative to the no‐injection case. If total brine leakage is considered, the results depend strongly on the assumed pre‐injection to post‐injection time frames and on the methods of normalization used to calculate incremental leakage. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd