sealPurdue News

June 1997

Research aims at nation's first 'smart' ground water regulations

WEST LAFAYETTE, Ind. -- A unique strategy on how to handle ground water pollution -- one that uses "smart laws" to benefit both the environment and agriculture -- may be in store for Indiana, and it may serve as a model for the nation.

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Purdue University agricultural engineer Bernie Engel says just like smart credit cards, smart kitchen appliances and other modern microprocessing miracles, environmental smart laws would use computers to examine the variables and prescribe solutions -- in this case, chemical regulations for specific areas.

Engel, at the request of the Office of the Indiana State Chemist, is working to create the nation's first smart environmental regulations for ground water contamination by agricultural runoff as part of the state's pesticide management plan required by the Environmental Protection Agency. The Office of the Indiana State Chemist, based at Purdue, is responsible for enforcing agrichemical regulations in Indiana.

"Other states apply blanket regulations, but Indiana is looking to do something somewhat different," Engel says. "Instead of just using one number, and saying that that is the proper amount of pesticide to use throughout the state, we're working to create an on-line computer data base and program that would tell pesticide users how much of the chemical they could use on a particular piece of land."

Currently, for example, every patch of soil is treated the same when it comes to regulations stating how much agrichemical can be used. Sandy or clay, wet or dry, hilly or flat, ground water that's shallow or deep, it doesn't matter one whit as far as the law is concerned.

For the amount of agrichemicals that seep into water, however, these varying conditions matter a great deal. So much, in fact, that Engel found that 75 percent of the detectable pesticides that seep into ground water come from just 25 percent of farmland.

Treating all fields the same doesn't make sense for farmers or for the environment when it comes to agrichemical regulations, Engel says.

According to Engel, there are 90 different major types of soil in Indiana, each with its own characteristics of pesticide movement into ground water. These characteristics were combined with other data from sources, such as the U.S. Geologic Service, the Natural Resource Conservation Service and the Indiana Department of Natural Resources, to create the first ground water vulnerability maps of Indiana.

Nitrate movement into ground water also is being mapped because it is somewhat similar to pesticide movement. (Excess nitrates in ground water are caused by excessive or improper fertilizer application or manure storage and disposal, and they can have harmful effects on wildlife and human health.)

In the near future, Engel plans to create more detailed maps of the areas of highest vulnerability so that farmers in those areas will know exactly where pesticides and fertilizers can be used safely.

"Right now we're using these maps for educational purposes, to see if we can assist those in the problem areas to avoid getting to the point where laws or regulations are necessary," Engel says. "If we get to the point where regulations are needed, on the other hand, it makes sense to not treat every situation the same. You may find that differences in conditions might make practices unacceptable that are used just a few miles away."

The next step for the research will be to incorporate site-specific information such as pesticide types, application rates, methods of tillage and other farming practices, and weather models for each area. Engel expects to have these more comprehensive and detailed maps within the next five years. Hoosier farmers then would be able to go to Purdue's World Wide Web site, plug in the variables for their situation, and plot out a map that details the acceptable levels for the chemical they intend to use.

"In more than five years you can let your imagination venture a bit more," Engel says. "A farmer's application computer might communicate with another computer to determine what's acceptable and what's not acceptable for that area and adjust the application rates without any direct human involvement.

"A lot of the technology needed to make this happen is already in place."

Engel says this type of system could greatly reduce the amount of chemicals moving into ground water. "There will still be agrichemical management problems such as spills or improper storage," he says. "But as far as nonpoint-source problems, we can do pretty well at reducing risk of leaching into ground water or runoff."

Beyond the realm of the possible, there will be another hurdle to clear before smart regulations are put into use, however. Those hurdles are all political, and they may prove to be the most difficult of all.

"If 'smart' regulations are to be used, assumptions that were implicit in the old regulations would become explicit in the new ones, and that makes it a whole new ball game," Engel says.

For example, assume, hypothetically, that current pesticide regulations were written so that there is a 10 percent risk of pesticides moving to ground water across the state. Using the new technologies, regulators decide to have "smart" regulations that limit the acceptable risk of pesticides moving into ground water to 2.5 percent. The regulators are feeling quite proud that they have reduced the risk of contamination of ground water by fourfold, when suddenly a citizen stands up and says, loudly, that he doesn't think any chance of any pesticide moving into their ground water is acceptable. The level of acceptable risk that had been hidden in the regulations has been forced out into public discussions, which could create new problems.

"Writing regulations in terms of risk is a very different concept from writing regulations as a yes/no, can or can't do it dynamic," Engel says. "The general public wants no risk, but there's always some risk with virtually anything."

Source: Bernie Engel, (765) 494-1198; e-mail,;
Writer: Steve Tally (765) 494-9809; e-mail,
Purdue News Service: (765) 494-2096; e-mail,

Photo Caption

This map shows the relative vulnerability of Indiana ground water to contamination by agrichemicals. Pesticides and fertilizers move into ground water at various rates, depending on a number of factors. Although current environmental regulations use a standard limit for the amount of these chemicals that can be used, Indiana regulators, with the help of researchers at Purdue, are considering implementing the nation's first "smart" environmental regulations that would take these varying factors into consideration for different regions of the state. (Purdue Agricultural Communications graphic by Bernie Engel and Russ Merzdorf)

Color copies of the graphic are available from the Purdue News Service. Photo ID: Engel/Smartlaws
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