Altering Dissolved Oxygen to Determine Flow Conditions in Fractured Bedrock Wells

A new approach to locate transmissive fractures and decipher vertical borehole flow conditions in fractured crystalline bedrock wells is presented, which uses dissolved oxygen (DO) as a benign tracer. The method was tested in two fractured crystalline bedrock wells previously characterized by televiewer and flow meter logging under both ambient and stressed (slug test) conditions. The method entailed elevating wellbore DO concentrations by circulating water through showerheads or injection of compressed air. The DO dilution was used to locate inflowing fractures. Changes in the DO concentration with time were used to ascertain flow within the borehole and to locate outflowing fractures and stagnant zones. Flow rates were also estimated. Fractures detected by the method corresponded to those observed by televiewer logging and for the most part were comparable to flow meter results. Given the effectiveness, time‐efficiency and low cost, the method is a promising alternative to other methods currently in use to characterize transmissive fractures in wells.

[1]  Jill L Libby.  An Unsteady State Tracer Dilution Method for Characterizing Water Contributing Fractures in Crystalline Bedrock Wells , 2012 .

[2]  P. Smart,et al.  A Tracer Methodology for Identifying Ambient Flows in Boreholes , 2011, Ground water.

[3]  J. Shafer,et al.  Variable‐Density Flow and Transport Simulation of Wellbore Brine Displacement , 2010, Ground water.

[4]  N. Weisbrod,et al.  The use of fluorescent dyes as tracers in highly saline groundwater , 2008 .

[5]  Olivier Bour,et al.  Comparison of alternative methodologies for identifying and characterizing preferential flow paths in heterogeneous aquifers , 2007 .

[6]  M. Kobr,et al.  A Simple Borehole Dilution Technique in Measuring Horizontal Ground Water Flow , 2007, Ground water.

[7]  N. Odling,et al.  Characterization of a Multilayer Aquifer Using Open Well Dilution Tests , 2007, Ground water.

[8]  R. Herbert,et al.  Pyrite oxidation by Acidithiobacillus ferrooxidans at various concentrations of dissolved oxygen , 2006 .

[9]  B. Dempsey,et al.  Heterogeneous oxidation of Fe(II) on ferric oxide at neutral pH and a low partial pressure of O2. , 2005, Environmental science & technology.

[10]  G. Robbins,et al.  A Tracer Dilution Method for Fracture Characterization in Bedrock Wells , 2004, Ground water.

[11]  K. Novakowski,et al.  Interpretation of injection-withdrawal tracer experiments conducted between two wells in a large single fracture. , 2004, Journal of contaminant hydrology.

[12]  A. Lasaga,et al.  The oxygen geochemical cycle: dynamics and stability , 2002 .

[13]  F. P. Haeni,et al.  Borehole-geophysical investigation of the University of Connecticut landfill, Storrs, Connecticut , 2002 .

[14]  Frederick L. Paillet,et al.  A Field Technique for Estimating Aquifer Parameters Using Flow Log Data , 2000 .

[15]  Florian Malard,et al.  Oxygen supply and the adaptations of animals in groundwater , 1999 .

[16]  Jeffrey H. Harwell,et al.  Influence of Rhodamine WT Properties on Sorption and Transport in Subsurface Media , 1993 .

[17]  S. Hall.  Single Well Tracer Tests in Aquifer Characterization , 1993 .

[18]  A. White,et al.  Measurement and Interpretation of Low Levels of Dissolved Oxygen in Ground Water , 1990 .

[19]  Peter Hufschmied,et al.  Determination of Fracture Inflow Parameters With a Borehole Fluid Conductivity Logging Method , 1990 .

[20]  A. Michalski,et al.  Characterization of Transmissive Fractures by Simple Tracing of In-Well Flow , 1990 .

[21]  A. Long,et al.  Monitoring Dissolved Oxygen in Ground Water: Some Basic Considerations , 1988 .

[22]  I. Marine.  Determination of the Location and Connectivity of Fractures in Metamorphic Rock with In‐Hole Tracersa , 1980 .

[23]  I. W. Marine,et al.  Determination of the location and connectivity of fractures in metamorphic rock with in-hole tracers , 1981 .

[24]  P. Smart,et al.  An evaluation of some fluorescent dyes for water tracing , 1977 .

[25]  H. Bouwer,et al.  A slug test for determining hydraulic conductivity of unconfined aquifers with completely or partially penetrating wells , 1976 .

[26]  Robert E. Selleck,et al.  Fluorescent Tracers for Dispersion Measurement , 1963 .