Predicting Missing Observations in Pesticide Data

From 2007 to 2011, researchers at the University of California, Davis and Waterbourne Environmental, Inc conducted a study to determine the relative ranking of potential areas of concern with respect to pesticide exposure to sensitive and endangered aquatic species in the Sacramento River watershed, San Joaquin River, and Bay-Delta estuary in California. The study involved the use of simulation modeling, historical water quality monitoring, and Geographic Information System (GIS) analysis in a weight-of-evidence context. A list of 40 pesticides published by the Central Valley Regional Water Quality Control Board in 2009 estimated to pose the highest risk to aquatic life (presented below) was used in their analysis.