Seasonal Changes in Concentrations of Dissolved Pesticides and Organic Carbon in the Sacramento–San Joaquin Delta, California, 1994–1996
By
James L. Orlando and Kathryn M. Kuivila
Table 14
Seasonal detections of pesticides 1994–1996.
[Values are percent detected out of the total number of samples analyzed in a given season; number in parentheses is the maximum concentration detected for a particular compound, in nanograms per liter. Numbers in brackets are
USGS National Water Information System (NWIS) parameter codes]
| | Total number of samples analyzed | Atrazine [39632] | Carbaryl [49310] | Carbofuran [49309] | Chlorpyrifos [38933] | DCPA [39771] | Diazinon [62682] | EPTC [82668] | Metolachlor [39415] | Molinate [50375] | Simazine [043035] | Trifluralin [82661] |
|---|
| Summer 1994 | 21 | 57.1 (121) | 9.5 (908) | 9.5 (60) | | | 4.8 (15) | 47.6 (878) | 71.4 (1,160) | 19.0 (1,090) | 66.7 (127) | 9.5 (17) |
| | | | | | | | | | | | | |
| Fall 1994 | 26 | | | | | 3.8 (20) | | | 15.4 (71) | | | |
| | | | | | | | | | | | | |
| Winter 1994 | 30 | | | | | | | | | | 96.7 (912) | |
| | | | | | | | | | | | | |
| Spring 1995 | 31 | | | 35.5 (958) | 3.2 (36) | | 3.2 (29) | | 25.8 (60) | | 80.6 (761) | |
| | | | | | | | | | | | | |
| Summer 1995 | 30 | | | | | | 3.3 (19) | 36.7 (176) | 63.3 (148) | 20.0 (441) | 3.3 (116) | |
| | | | | | | | | | | | | |
| Summer 1996 | 15 | | 13.3 (111) | | 6.7 (28) | | | 60.0 (87) | 73.3 (188) | 86.7 (269) | 13.3 (23) | 6.7 (11) |