An SA government investigation has been undertaken to determine the extent of groundwater pollution resulting from the waste disposal practices used at the now abandoned Kongorong cheese factory. During the period 1924 to 1971, liquid effluent from the factory was disposed of by various seepage methods in an area of karstic limestone occurrence. The results have shown that the waste disposal practices have caused near-surface groundwater contamination in both an upper unconfined aquifer and a lower, partially confined aquifer. It has not been possible to accurately define the limits of the pollution plume in the unconfined aquifer due to the areal distribution of water quality data, the influence of other pollution sources and the various locations of the waste disposal sites. The pollution plume within the partially confined aquifer, however, is considered to be of only limited extent, and occurs in the vicinity of a deep drainage well. Groundwater supplies in the Kongorong area are likely to now contain elevated nitrate ion contents which may render the supplies unsuitable for human consumption, but, with the exception of an area immediately to the east and south-east of the cheese factory site, the groundwater should still be suitable for other uses. Further work is recommended to more accurately define the groundwater flow regime, and to assess the head differences between the two sub-aquifers. Montoring of groundwater quality in a few selected wells is also recommended.