University of Missouri Extension

WQ21, Reviewed October 1993

Agricultural Sources of Contaminants in Groundwater

Daryl Buchholz
Department of Agronomy

In agriculture, pesticides and plant nutrients can enter the groundwater and contaminate it. These chemicals may reach large enough levels to become harmful to animals and people. So we must understand how contamination may occur and how it can be avoided. With good management practices, we can keep the groundwater from becoming contaminated by agricultural chemicals.

Agricultural sources of contamination

The following substances used on the farm have the potential to contaminate groundwater:

How do these chemicals become groundwater contaminants?

Nitrogen does occur naturally. Commonly grown legume plants, such as soybeans and alfalfa, produce nitrogen. This nitrogen also changes into nitrate. One cannot distinguish between these naturally occurring sources of nitrates and those added by fertilizers or animal wastes.

Nitrates can contaminate groundwater if more nitrate is applied to the soil than the plants and soil can use.

This publication was written by Karen DeFelice, former associate extension agronomist; Nyle Wollenhaupt, former state extension agronomist; and Daryl Buchholz, state extension agronomist. This material is based upon work supported by the United States Department of Agriculture, Extension Service, under special project number 89-EWQI-1-9203.
WQ21 Agricultural Sources of Contaminants in Groundwater | University of Missouri Extension

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