Applications of universal kriging to an aquifer study in New Jersey

This article describes the use of kriging for optimizing data collection and utility in a regional ground-water investigation of the Potomac-Raritan-Magothy aquifer system in central New Jersey. Kriging was used to (1) estimate the altitude of an aquifer surface, (2) estimate hydraulic conductivities from point data, and (3) estimate the associated kriged errors. The selection of locations for additional data collection, based on the kriged errors, was effective in terms of improving the aquifer surface data base. In another application, hydraulic conductivity values were kriged, first using equal weights, then unequal weights to account for the reliability of the data. The weighting values that were used for unequal weighting were estimated by an analysis of variance. Although inclusion of the data reliability in the kriging will increase the kriged errors, the accuracy of the range of uncertainty in the interpolated values also increases.