USGS scientist using an autotrace to extract pesticides from water samples in preparation for gas chromatography/mass spectrometry (GC/MS) analysis. The autotrace automates the processing of large numbers of samples.

A liquid chromatography/mass spectrometry (LC/MS) instrument with an on-line solid phase extraction (SPE) system used for the analysis of pesticides in water. SPE provides for shorter total analysis times, the ability to automate analysis procedures, and much smaller sample volumes for analysis.

USGS scientist preparing a sediment sample for the analysis of herbicides. USGS scientists developed an analytical method for the ultratrace analysis of herbicides in soil that combined solid-phase extraction (SPE) and enzyme-linked immunosorbent assay (ELISA).

Incorporating an encapsulated herbicide (atrazine) into the soil as part of an experiment to determine if encapsulating herbicides reduces runoff. The white pipes are suction cup lysimeters used to sample water from the unsaturated zone.