Limited resources for groundwater quality monitoring projects demand definition of groundwater contaminant plumes with a minimum number of sampling wells. The relationship between loss of information (or plume definition error) and degree of reduction in the number of sampling wells has been investigated by the authors. A proprietary sampling design product (E4) was used to select variably sized subsets of sampling wells from two existing natural gradient tracer tests. The tracer plume defined by data from each subset of wells was compared to the plume defined by data from the full set of wells. Differences between each subset plume and its corresponding full set plume were quantified and used to generate an error versus sampling density and time since tracer introduction function. Combined analysis of three sampling events from one tracer test and two from another revealed that the number of wells used for four of the events could have been reduced with minimal loss in contaminant plume definition. This suggests that E4 may be applied in the design of groundwater monitoring well networks.
- Groundwater monitoring
- fractional factorial
- network design
- © International Association on Water Quality 1993