Submitted by: agcomm,  Wed Dec 31 10:25:49 1997


                         December 31 1997
Computer Technology, Soil Surveys Combined in Groundwater
Protection Effort 
     The touch of a button or the click of a computer mouse can
help some North Dakota farmers and land managers protect
groundwater, thanks to efforts by North Dakota State University
agricultural engineers.
     The engineers combined information from county soil survey
maps, a Geographic Information Systems (GIS) computer program and
a system designed to assess risk to groundwater from pesticides.
That information can help producers and land managers chose
pesticides and management practices that work best while
protecting water. 
     John Nowatzki, a water quality specialist with the NDSU
Extension Service, developed the computer application based on a
risk assessment system developed by NDSU water quality specialist
Bruce Seelig.
     "The original assessment system was intended to help make
management recommendations under local conditions," explains
Seelig, who developed the system about four years ago.
     The system takes into account the properties of a proposed
pesticide, such as how easily it adsorbs to the soil and how fast
it breaks down.  Based on information from the soil maps, the
system includes data on soil texture and permiability, hydrologic
factors such as the depth to the aquifer and the flow of water to
and from the water table and, finally, data on soil organic
matter, since organic matter tends to adsorb pesticides. 
     "As we looked at the scientific data and research, those
seemed to be the common factors that had the largest impact on
pesticide movement and potential groundwater contamination,"
Seelig says.
     If a producer's land overlays an aquifer, the system helps
determine aquifer's sensitivity to pesticide contamination.  At
the same time, the system is designed to help the producer decide
which types of management methods would best protect water
resources. 
     Although Seelig sought to keep the system simple, use has
been limited since it was developed. "It was just more than the
typical person wanted to go through to get the information," he
says.
     That's where Nowatzki's computer and GIS expertise comes in. 
Using soil survey maps that have been computerized by the USDA
Natural Resource Conservation Service, he's  been able develop a
more user-friendly version of the assessment. 
     "With the system, producers can call up the maps, look at a
field and learn the potential groundwater risk," Nowatzki
explains.  "That information will help them select pesticides
with the least potential to contaminate groundwater." 
     Likewise, township and county officials responsible for
noxious weed control can use the GIS maps to make sure highly
mobile pesticides are not applied over vulnerable aquifers, he
says.
     Currently, the computerized pesticide assessment system has
been applied only to  McIntosh County.  Sensitivity Maps for
McIntosh County can be viewed on the Ag & Biosystems Pesticide
Assessment Homepage at this web address:
http://www.ageng.ndsu.nodak.edu:83/.  More detailed maps at the
township and section level are available by contacting Nowatzki
at the NDSU agricultural and biosystems engineering department.
     Nowatzki is in the process of applying the GIS computerized
assessment system to other North Dakota counties.  He also plans
to have a GIS computer application of a surface water assessment
system developed next year.  That system will help producers make
decisions that will help protect the states rivers and lakes from
pesticide contamination. 
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NDSU Agriculture Communication
Sources: John Nowatzki (701) 231-8213
Bruce Seelig (701) 231-8690
Editor: Tom Jirik (701) 231-9629