Identification of groundwater-producing fractures by using an electromagnetic borehole flowmeter in monitoring wells on the Oak Ridge Reservation, Oak Ridge, Tennessee

Abstract

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

FY94 site characterization and multilevel well installation at a west Bear Creek Valley research site on the Oak Ridge Reservation

“…Measurements were repeated until the standard deviation fell within acceptable limits (<0.005 V). Moore and Young (1992) reported being unable to conduct EM flowmeter tests in some areas due to high background noise.…”

“…An electromagnetic (EM) borehole flowmeter developed by TVA was used in the open interval below the temporary casing to identi@ the location and relative flow rate of individual fracture zones contributing groundwater flux into or out of the boreholes. The EM flowmeter measures a voltage induced by the movement of ions carried by groundwater as it flows through a metal cylinder containing a magnetic coil that is positioned vertically within the borehole (Moore and Young, 1992). The cylinder is surrounded by a packer that prevents flow from circumventing the cylinder.…”

Environmental Sciences Division Groundwater Program Office report for fiscal years 1995--1997

“…The pumping well is screened from 6-22 m bgs and the shallow and deep wells are screened from 4-7 m bgs and from 19-22 m bgs, respectively. Three additional boreholes were drilled and continuously cored, and borehole characterization was done using flowmeter and point dilution testing (Moore and Young, 1992;Sanford and Moore, 1994;Moline and Schreiber, 1996). The boreholes were subsequently instrumented with multilevel samplers to facilitate discrete fracture zone monitoring and comparison with standard screened wells.…”

The deep hydrogeologic flow system underlying the Oak Ridge Reservation -- Assessing the potential for active groundwater flow and origin of the brine

“…This conclusion calls for parameterestimation techniques that are more suitable for fractured media than the ones practiced in the past on the ORR. Borehole methods that use concentration gradients in space and time (Ronen et al 1986;Tsang et al 1990) or accurate flow-meter measurements in packed intervals (Moore and Young 1992) were designed specifically for dual-porosity, dual-permeability environments and hence, could be more successful. One of the few flow measurements carried out in the deep flow system at corehole CH-9 (where saline water was documented) revealed high flux at a depth exceeding 100 m (328 fi) (Moore and Young 1992) (Fig.…”