A conventional soil-solution sampler was modified to prevent loss of volatiles, which tend to escape from the liquid sample during sample collection. The sampler is connected to a purging chamber, which is in turn connected to a trap packed with Tenax resin. The sample is collected by applying a vacuum to the downstream end of the trap. Material that volatilizes during collection of the aqueous sample is captured on the trap. Material that remains in the aqueous sample is purged from solution with N2 and captured on the same trap. The trap is then returned to the laboratory for desorption and determination of the individual pollutants by conventional methods for volatile organic analysis.