California report on pesticdes in ground water

Below is a press release from the California Department of Pesticide
Regulation announcing the release of the 1996 report on the results of
ground water testing for pesticides.  I have omitted the background tables
in the interest of saving space.  Single copies of the report can be
obtained free from: Environmental Monitoring and Pest Management Branch,
Department of Pesticide Regulation, 1020 N Street, Sacramento, California
95814, U. S. A. phone (916) 324-4100, FAX (916) 324-4088, or by e-mail to
dbartkowiak@cdpr.ca.gov.   The executive summary is also available in the
"Publications" section of DPR's Web page: http://www.cdpr.ca.gov.  Media
should contact Veda Federighi (916) 445-3974.

Kathy Brunetti, Agriculture Program Supervisor
California Department of Pesticide Regulation
1020 N Street Room 161,  Sacramento, California, USA 95814-5624
voice (916) 324-4100,  FAX (916) 324-4088,  brunetti@empm.cdpr.ca.gov

SACRAMENTO April 16, 1997-- Cal/EPA's Department of Pesticide Regulation
(DPR) has released its 1996 report on the results of ground water testing
for pesticides. The annual report is required by the Pesticide
Contamination Prevention Act of 1985 (AB 2021, Connelly). Among other
provisions of the law, government agencies that test well water for
pesticide residues must report the results to DPR.
     The report summarizes ground water monitoring from six well sampling
surveys submitted to DPR between July 1995 and June 1996. The monitoring
was done between 1994 and 1996 by DPR and by the California Department of
Health Services. Samples were taken from 3,564 wells in 48 of California's
58 counties. Pesticide residues were detected and verified in six private
drinking water wells in five counties (Butte, Kern, Monterey, San Joaquin,
and Sutter). The levels of contamination were below levels of health
concern. (See attached table for details on county detections.) **Table
omitted for this posting.**
     Most samples were analyzed for multiple chemicals. Overall, the tests
targeted a total of 121 pesticide active ingredients and breakdown
products. Of those, verified detections were made of three herbicides:
atrazine, bromacil, and simazine, all of which have previously been
detected in ground water.
     In addition, three other agricultural chemicals were found that are
recurring contaminants of ground water but have not been used in several
years: DBCP, 1,2-D, and ethylene dibromide. There were also unconfirmed
detections of 10 other pesticides that are no longer registered. DPR does
not conduct follow-up sampling to verify these detections because there is
no need to put use restrictions on chemicals no longer being used.
     "Until 20 years ago, the scientific consensus was that
pesticides--because of their chemical makeup--could not pollute ground
water," said James W. Wells, DPR Director. "That perspective changed in the
mid-1970's, when we began to find ground water contamination by pesticides.
     "By the mid-1980's when the Pesticide Contamination Prevention Act was
passed, the fear was that scores or hundreds of pesticides would be found
in ground water," Wells added. "Since then, we have been collecting data on
well water sampling, and doing extensive monitoring of our own. Since 1985,
more than 20,000 private and public wells throughout the state have been
tested for nearly 300 different pesticides.
     "We have found that relatively few pesticides get into ground
water--less than two dozen different chemicals," said Wells. "We continue
to find these contaminants-- primarily herbicides--in many areas where the
soil conditions favor movement of pesticides to ground water. However,
beyond these few chemicals, the predictions of extensive contamination
haven't been borne out by monitoring."
     During this time, the Department has also carried out several programs
to prevent ground water contamination, Wells said. For nearly a decade, for
example, DPR staff have been training pest control advisors on methods of
preventing pesticides from reaching ground water. The Department also
requires advisors to write ground water protection advisories incorporating
these methods before certain pesticides can be used in areas of the state
known to be vulnerable to contamination.
     Last year, DPR and the University of California began a three-year
project working with growers, pest control advisors, the agricultural
industry, and herbicide manufacturers to develop techniques to reduce or
prevent ground water contamination. The project focuses on herbicide use in
grape and citrus production in Fresno and Tulare Counties, where simazine,
diuron and bromacil have been found in several hundred wells. More than 70%
of the use of these three herbicides is in grape or citrus in the two
     In addition, "DPR scientists have developed a lot of data on how
climate, soil type, geography and a pesticide's chemical composition
contribute to ground water contamination," Wells said. That data will be
the scientific foundation of additional regulatory measures to be
introduced later this year.

Kathy Brunetti