heinson_C1(1) - Remote monitoring of groundwater flow in...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
2 nd International Salinity Forum Salinity, water and society–global issues, local action 1 Remote monitoring of groundwater flow in fractured rock using electrokinetic methods Adrian Costar 1 , Tania Wilson 1 , Graham Heinson 2 , Andy Love1, Zoe Smit 2 1 School of Earth and Environmental Sciences, University of Adelaide, SA 2 Department Water, Land, Biodiversity Conservation SA, Adelaide, Australia Introduction Traditional measurement of groundwater flow in porous or fractured media requires a pumping well and an observation well. Hydraulic conductivities are inferred from draw-down characteristics during a pump test, and in general, simplifying assumptions of radial homogeneity have to be made. The primary disadvantages are the high cost of drilling one or more observation well, and in the extrapolation of a point measurement to a spatially heterogeneous media. An alternative method is to measure electrokinetic (or streaming) potentials, generated by sub -surface fluid -flow (Fagerlund and Heinson, 2003) . Such potentials arise from the diffusion electrical potential (o r zeta potential) across boundaries between a fluid electrolyte and mineral grains or rock particles in fractured and porous media. Advantages of this method are that electrode arrays can be quickly and cheaply deployed, and that observation wells are not required. This paper presents results of electrokinetic potential experiments surrounding > 20 pumping wells in the Adelaide Hills, South Australia. Arrays of 36 electrodes were deployed in a radial pattern with six electrodes every 5 m along a line, and with six lines spaced 60 °. Potentials were measured every 5 s at each electrode relative to a distant reference electrode. In many cases, existing in-hole pumps were used. Transient changes in electrical potential surrounding the pumped well of up to 1 0 mV are observed over time-scales of a few seconds after turning the pump on, to tens of minutes when equilibrium flow is established. We note that spatial patterns of potentials, and hence
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

heinson_C1(1) - Remote monitoring of groundwater flow in...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online