The use of interwell partitioning tracers to quantify the amount of nonaqueous phase liquid (NAPL) in porous media has been demonstrated in several laboratory and field tests. The primary emphasis of work to date has been on the use of first temporal moments of tracer breakthrough curve (BTC) data to estimate the average NAPL saturation. Here we extend the data analysis to the use of tracer BTC second and third temporal moments to estimate the statistical parameters characterizing the NAPL spatial distribution. In particular, we examine the fraction f of the streamlines that contain NAPL and the mean and standard deviation of the distribution of streamline trajectory-average NAPL saturations. Two models are presented based on discretizing tracer swept volumes into contaminated and uncontaminated zones. The models are applied to data from three-dimensional numerical simulations, two-dimensional flow laboratory experiments, and field tests at two sites (Hill Air Force Base, Utah, and a dry cleaner in Jacksonville, Florida). For all cases considered here, good agreement was found between expected (measured) and estimated values of f, the fraction of the tracer swept zone that contained NAPL. The effects of nonlinear and nonequilibrium partitioning as well as correlations between NAPL saturation and saturated hydraulic conductivity are also considered.