Agriculture Reference
In-Depth Information
•
Consider whether your application method presents any special risks.
For example, soil injection of some pesticides may not be wise when
groundwater is close to the surface.
•
Take precautions to keep pesticides from back-siphoning into water
source.
•
Locate pesticide storage facilities at least 100 feet from wells,
springs, sinkholes, and other sites that directly link to groundwater to
prevent their contamination from runoff or firefighting water.
•
Whenever possible, locate mixload sites and equipment-cleaning sites
at least 100 feet from surface water or from direct links to ground wa-
ter. This will help prevent back-siphoning, runoff, and spills from
contaminating the water sources. If you must locate one of these
work sites near a water source, use methods such as dikes, sump pits,
and containment pads to keep pesticides from reaching the water.
•
Do not contaminate groundwater through improper disposal of unused
pesticides, pesticide containers, or equipment and container rinse wa-
ter. Dispose of all pesticide wastes in accordance with local, state,
tribal, and federal laws.
b.
Water on the Treated Surface
If there is more water on the soil than the soil can hold, the water (along
with any pesticides it contains) is likely to move downward to the groundwa-
ter. Prolonged heavy rain or excessive irrigation will produce excess water on
the soil surface (see
Figure 9.5
)
.
Rain
If weather forecasts or your own knowledge of local weather signs cause
you to expect heavy rain, delay outdoor handling operations—including mix-
ing and loading, application, and disposal—to prevent wash-off, surface run-
off, or leaching.
Irrigation
Pesticide movement into groundwater is affected by both the amount of
water used in irrigation and how soon before or after a pesticide application the
irrigation is done. If irrigation water contains pesticides, be careful to prevent
it from flowing into water sources.
