Effects of Sampling and Analytic al Procedures on the Measurement of Geochemical Indicators of Intrinsic Bioremediation: Laboratory and Field Studies Evaluates the effects of various samplin g and analytical methods of collecting groundwater geochemical data for intrin sic bioremediation studies. Sampling and analytical methods were tested in th e laboratory and in the field. Several groundwater sampling and analytical methods may be appropriate for measuring geochemical indicators of intrinsic bioremediation. The methods vary in accuracy, level of effort, and cost