Risk, G.F. 1980 Tests of the applicability of electrical prospecting methods for detecting underground seepage of pulp and paper mill effluent at Kinleith. [s.l.]: [s.n.]. Report / Geophysics Division 170 19 p.
Abstract: A portion of the effluent discharged from the New Zealand Forest Products (NZFP) pulp and paper mill at Kinleith is discharged via seepage ponds into the local ground water at a rate of about 10 megalitres per day. As part of a programme to gain a better understanding of the manner in which the effluent disperses, NZFP asked Geophysics Division to advise them on the feasibility of using resistivity prospecting techniques for detecting the presence of effluent in the ground. Fifteen resistivity soundings were made near Kinleith within five km of seepage ponds which discharge saline water into the local ignimbrite aquifers. Further than about 1 km from the ponds, the presence of pollutants in the ground becomes undetectable with surface soundings because the polluted aquifer has insufficient resistivity contrast in comparison to the unpolluted ignimbrites above and below. Downhole electrical conductivity logging has clearly demonstrated the presence of dilute effluent in the Kinleith aquifer below 28 m depth in a drill hole 2 km from the seepage ponds. (auth)