skip to main content


Title: Delineating Area of Review in a System with Pre-injection Relative Overpressure

The Class VI permit application for geologic carbon sequestration (GCS) requires delineation of an area of review (AoR), defined as the region surrounding the (GCS) project where underground sources of drinking water (USDWs) may be endangered. The methods for estimating AoR under the Class VI regulation were developed assuming that GCS reservoirs would be in hydrostatic equilibrium with overlying aquifers. Here we develop and apply an approach to estimating AoR for sites with preinjection relative overpressure for which standard AoR estimation methods produces an infinite AoR. The approach we take is to compare brine leakage through a hypothetical open flow path in the base-case scenario (no-injection) to the incrementally larger leakage that would occur in the CO 2-injection case. To estimate AoR by this method, we used semi-analytical solutions to single-phase flow equations to model reservoir pressurization and flow up (single) leaky wells located at progressively greater distances from the injection well. We found that the incrementally larger flow rates for hypothetical leaky wells located 6 km and 4 km from the injection well are ~20% and 30% greater, respectively, than hypothetical baseline leakage rates. If total brine leakage is considered, the results depend strongly on how the incremental increasemore » in total leakage is calculated, varying from a few percent to up to 40% greater (at most at early time) than base-case total leakage.« less
 [1] ;  [1] ;  [1] ;  [2] ;  [2]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. Montana State Univ., Boseman, MT (United States). Big Sky Carbon Sequestration Partnership
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Energy Procedia
Additional Journal Information:
Journal Volume: 63; Journal Issue: C; Journal ID: ISSN 1876-6102
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Fossil Energy (FE)
Country of Publication:
United States
58 GEOSCIENCES; area of review; Class VI; overpressure; underpressure; hydrostatic pressure; USDW
OSTI Identifier: