30 µg/L Atrazine: The peak concentration of atrazine detected in any sample within the Chesapeake Bay was 30 µg/L (station L0002488), which is located in a tributary on the Eastern Shore shown in Figure 1. (US EPA 2006)
 
2)    10 µg/L Atrazine: The general trend in the data indicates that the main detections of atrazine are in the tributaries while significantly lower concentrations have been found in the Bay itself. During June of 2011, atrazine concentrations from the upper Chop Tank River were logged. The average of all recorded concentrations was 0.29 µg/L. The highest recorded concentration was 10 µg/L (Chesapeake Bay Program; USDA: Hively et al. 2011).
 
3)     3µg/L Atrazine: The EPA’s Maximum Residue Limit (MRL) for atrazine is relevant because it is the limit which the EPA has set forth regulating our drinking water (U. S. EPA MRL).