Uranium, arsenic, and nitrate were the inorganic constituents that were most frequently detected at high concentrations, mostly in shallower wells. High and moderate concentrations of arsenic were detected in deeper wells.
This study of untreated groundwater indicates the number of samples in which inorganic or organic constituents occur in high or moderate in concentration. The study does not indicate significant problems in groundwater quality here.
Vanadium and boron were detected at high and moderate concentrations in this area. High concentrations for these constituents were detected almost exclusively in samples collected in the Temecula Valley study area.
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.