[Site 11 was not sampled during the period. The following pesticides were not detected in any samples: alachlor, atrazine, butylate, carbaryl, carbofuran, chlorpyrifos, cyanazine, DCPA, fonofos, malathion, methidathion, napropamide, pebulate, thiobencarb, and trifluralin. Concentrations are shown in nanograms per liter. Numbers in brackets are USGS National Water Information System (NWIS) parameter codes. hh, hours; id, identification; mm, minutes; mm/dd/yyyy, month/day/year; nd, not detected; ( ), detected at a concentration less than the method detection limit]