What causes changes in the hydrology, the ecology and the water quality of the Sacramento-San Joaquin River Delta and the San Francisco Bay estuary? These studies help state and local agencies manage resources well.
Arsenic and boron were the trace elements that most frequently occurred at high concentrations. Fumigants (pesticides) were detected at high concentrations in 3% of the primary aquifers. Herbicides and insecticides were detected at low concentrations.
The constituent present at high concentrations in the greatest proportion of the primary aquifer system was TDS, which is an indicator of salinity. Perchlorate was also present at moderate concentration in 42% of samples.