Abstracts

298 - Fracture network and groundwater flux characterization
using a suite of high resolution methods in a sedimentary
bedrock aquifer
Lucas A.F.S. Ribeiro, Jessica R. Meyer, & Beth L. Parker
G360 Centre for Applied Groundwater Research, School of Engineering, University of
Guelph, Guelph, Ontario, Canada
In fractured rocks, contaminant distribution and flux are strongly influenced by the characteristics
and connectivity of fracture networks. This study focuses on characterizing the
fracture network and hydraulics along a 2-D transect down-gradient of a DNAPL source
zone in sedimentary rock. Five boreholes were continuously cored along the transect to
depths between 55 and 63 mbgs. The lithology, sedimentary structures, and fractures observed
in core were described in detail and were complemented by a comprehensive suite of
borehole geophysics collected in the open boreholes. Active line source (ALS) temperature
logging was collected in FLUTe lined holes to identify hydraulically active fractures under
ambient conditions and hydraulic conductivity data were collected from FLUTe transmissivity
profiling and straddle packer testing. Additionally, transient hydraulic heads were
collected using transducer arrays installed behind FLUTe liners. The data collected from
the core and open and lined boreholes were used to design Westbay MLSs to provide high
resolution head profiles. 3-D fracture network characterization is achieved by combining
the 5 transect borehole datasets with 11 boreholes containing similar datasets. Fracture
scan-line surveys were also done in analogous formations in outcrops to provide regional
structural trends and to inform fracture lengths, especially for vertical joint sets that inform
the mechanical unit boundaries. The application of numerous high resolution borehole
methods and the combined use of surface and borehole fracture datasets contribute to the
definition of the site specific fracture network. The fracture network information is then
integrated with the hydraulic data to provide robust estimates of groundwater flux across
the 2-D transect enhancing the understanding of the present contaminant distribution and
providing key information for discrete fracture network numerical models for groundwater
flow and contaminant transport.
POSTER SESSION:
Groundwater Issues from Mining &
Aggregates
Thursday October 29, 16:40
Room: Regent
169 - Numerical Groundwater Modeling of the Lithium Brine
Extraction at the Salar de Atacama
152 IAH-CNC 2015 WATERLOO CONFERENCE