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50 Ways Farmers Can Protect Their Groundwater
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50. Take Precautions When Chemigating

anti-pollution safeguards

Chemigation, the application of agrichemicals through an irrigation system, has some advantages over other application techniques: it applies pesticides more uniformly; it reduces mechanical damage to crops; and it reduces hazards to the operator. However, you need to supervise a chemigation system carefully to prevent overwatering with the water-chemical mixture.

When you chemigate, install and properly maintain several protective devices. The irrigation pipeline check valve prevents the chemical and water mixture from backflowing into the well. The vacuum relief valve on the irrigation pipeline also prevents backflow of chemical solution. The inspection port is used to check how the valves are working.

anti-pollution safeguards The automatic low-pressure drain is used to drain the chemical and water mixture left in the lines when the system is turned off. The drain should discharge the chemical and water mixture at least 20 feet from any water supply. The chemical injection line check valve prevents the flow of fluid back toward the injection pump. Electronically interlocked control panels will stop the chemical from pumping whenever the water pump stops.
check your unattended system frequently To prevent contamination of groundwater from chemigation, check your unattended system frequently. And always use the least amount of water possible. Use only enough water to transport and activate the chemical. Also, don't apply a chemical through a chemigation system unless the container label says it is all right.
sprinkler system Don't chemigate with a sprinkler system if wind speeds are greater than 5 miles per hour; otherwise, the chemical could drift. Don't connect your irrigation system directly to a public water supply when using chemigation. This is illegal in most states. Also, don't inject agrichemicals into your irrigation system on the suction side of the irrigation pump. This is illegal and defeats the purpose of the system's safety devices.

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