General Considerations

1. Relative risk of:

a. Spray irrigation

	Spray irrigation of top water or slurry from manure storage, earthen basin, or undersized anaerobic lagoon	Corresponding magnitude of risk
	Spray irrigation of top water from lagoon designed according to standard engineering designs.
	Spray irrigation of top water from aerobic lagoon, purple lagoon, or lagoon designed for odor control (permanent pool twice as large as standard engineering designs)

b. Tanker or towed hose application

	Surface application of stored slurry manure	Corresponding magnitude of risk
	Surface application of slurry manure followed by same day incorporation OR Surface application with drop hose applicator
	Subsurface injection of slurry manure

c. Solid manure spreader

	Surface application of wet solid manure	Corresponding magnitude of risk
	Surface application of dry or heavily bedded solid manure
	Surface application of dry or heavily bedded solid manure followed by same day incorporation OR Immediate incorporation of wet solid manure

2. Have other odor treatment technologies been adopted for the manure storage or lagoon?

	Independently documented odor control additive OR Anaerobic lagoon sized for odor control OR Purple lagoon	Corresponding magnitude of risk
	Anaerobic digestion OR Aerobic treatment OR Composting

Timing of Manure Application

3. Time of day?

	Time of day is not commonly considered. Evening application is common.	Corresponding magnitude of risk
	Commonly applied during daylight hours before 5 pm.
	Always applied during daylight hours after 8 am and before 5 pm.

4. Weather conditions?

	Weather conditions are not usuallly considered.	Corresponding magnitude of risk
	Commonly applied on sunny, windy days.
	Always applied on sunny, windy days.

5. Weekends/Holidays?

	Weekends and holidays are not usually a consideration.	Corresponding magnitude of risk
	Weekends and holidays are commonly avoided.
	Weekends and holidays are always avoided.

Spray Irrigation Considerations

6. Type of spray nozzle?

	Big guns or high-pressure nozzles that direct spray into the air.	Corresponding magnitude of risk
	Low-pressure drop nozzles that release liquid above crop canopy.
	Low-pressure nozzles that release liquid below crop canopy.

7. Dilution with fresh water?

	No dilution.	Corresponding magnitude of risk
	Mixing of fresh to lagoon water at a ratio of less than 3 to 1.
	Mixing of fresh to lagoon water at a ratio of 3 to 1 or greater.

8. Time of year for application (for anaerobic lagoons only)?

	Spring (shortly after lagoon has become active) or winter (when lagoon is inactive).	Corresponding magnitude of risk
	Early summer (after lagoon has been active for 2 months or more).
	Mid summer through fall (when lagoon has been active for several months).

9. Time delay between last lagoon feeding and spray irrigation?

	Lagoon receives manure within few days of spray irrigation from lagoon.	Corresponding magnitude of risk
	Manure flow to lagoon is stopped for two weeks prior to spray irrigation from lagoon.

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