33 D12. Hydrogeology (Posters)

Sunday, 4 November 2018
9:00 AM - 5:30 PM
Halls J-K

IDENTIFYING CROSS-WELL FRACTURE CONNECTIONS USING THE DISSOLVED OXYGEN ALTERATION METHOD

Paper number: 33-1
Program: Technical Sessions
Time: 9:00 AM – 5:30 PM

Authors

Abstract

Determining how wells in fractured crystalline bedrock are interconnected is important in defining contaminant flow pathways and interpreting water quality data from wells. Although various tracers and geophysical techniques have been successfully used, the high cost or logistics may restrict their implementation. This study demonstrates a low-cost technique for identifying fracture connections between wells by combining the dissolved oxygen alteration method (DOAM) with cross borehole hydraulic tests. Following alteration of the dissolved oxygen (DO) profile in the observation well, an interconnected well is pumped, which results in changes in borehole flow in the aerated observation well. The DO profile in the observation well is monitored over time to identify fractures that hydraulically connect to the pumping well. The method was demonstrated at three test sites in Storrs, Connecticut. Each site has two or three interconnecting wells in fractured crystalline bedrock and varying flow conditions. The DOAM successfully identified interconnecting fractures in wells 15 m to 84 m apart.

Geological Society of America Abstracts with Programs. Vol. 50, No. 6

doi: 10.1130/abs/2018AM-318870

© Copyright 2018 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.