Chemicals are dispersed accidentally, deliberately, or by weather-related events. Rapid mapping of contaminant distributions is necessary to assess exposure risks and to plan remediation. Powdered aspirin or caffeine was dispersed across a concrete driveway using the exhaust port of a shop vacuum cleaner. Water-soaked, cotton-swab, wipe samples were collected to map the dispersant distribution. An autosampler/direct analysis in real time (DART [IonSense, Saugus, MA])/time-of-flight mass spectrometer was used to acquire an ion chromatogram for the most abundant ion. A semi-quantitation map for several levels of caffeine was plotted to demonstrate the feasibility of applying this technology to contaminated sites.