Substantial TCE and ammonium contamination was detected in groundwater beneath a residential area in Perth, Western Australia. Investigation has successfully determined broad aspects of the extent of the TCE plume and its impact. The advective front of the plume in groundwater is approximately 600 m downgradient from an industrial area. The contamination is about 300-400 m wide and 6-8 m thick. A maximum concentration of 2,000 μg/L TCE was measured. The true peak concentration, however, is expected to considerably exceed this value. A retardation factor, R, for TCE of 1.8 is estimated. Based on R and the groundwater velocity, the residence time for TCE in the aquifer is estimated to be approximately 16 years. Biological or chemical transformation of TCE cannot be excluded, although no transformation products have been observed in a small portion of the plume. Currently, no remediation of the contaminated site is planned. An approach for managing the contamination is presented and important issues for future remediation options for TCE- contaminated sites in Perth are discussed.