Saltwater intrusion in Southern Eyre Peninsula, December 2009

groundwater salinity readings, measured at field were at range of ~6000uS/cm, which has
decreased over time to 1530 uS/cm. To confirm groundwater salinity from the sump
section and better understand its origin this groundwater should be pumped out prior to
the next round of salinity profiling.
Monitoring site ULE 205 (Quaternary Limestone and Tertiary Sand
Aquifers)
Drilling
In the lithological log of the ULE 205 it was not indicated that the Uley Formation (clayey
sand/ sandy clay) is present,
Salinity profiling
The review of downhole geophysical logging data (Gamma log) suggests that the Uley
Formation may be present at this location (~1 – 1.5 m thick) and to an unknown degree
separates the Quaternary Aquifer from the underlying Tertiary Aquifer, as marked in
Figure 5.
A scale of gradual increase in the groundwater salinity with depth through this zone 90.3
– 91.3 m (-23.23 to -24.23 mAHD) is higher than in the overlying Quaternary Aquifer, but
lower than in the underlying Tertiary Aquifer, as marked in Figure 6.
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