(a) Manure slurries and sludges shall not be applied where the land slope exceeds five (5) percent or the yearly soil loss is greater than five (5) tons per acre as determined by the Universal Soil Loss Equation or in any manner that will allow surface runoff to transport animal waste from the application site.
(b) The minimum depth of unsaturated soil strata on which a land application system may be developed is four (4) feet.
(c) All land application sites shall be protected from up slope runoff by diversion ditches capable of intercepting the overland flow from a 25-year 24-hour storm event. Diversion ditches are not required if it can be shown that a storm of this size will not have an impact on the site.
(d) Pathogen controls. - (i) Spray irrigation application shall not leave the property used as the land application site.
- (ii) Manure slurries and sludges shall be applied only to lands with a very low potential for public access.
- (iii) Public access to all application sites shall be restricted by signing at points of potential public access. The access restriction shall apply one (1) year after the application of manure slurries.
- (iv) Crops shall not be harvested for ninety (90) days after the application of manure slurries and sludges.
- (v) Direct human consumption crops, which are consumed fresh, shall not be harvested for one year after the application of manure slurries and sludges.
- (vi) Turf grass or sod grown on land where manure slurries or sludges are applied shall not be harvested for one year after application of liquid animal wastes.
(e) Buffer zones shall be required to protect the public from exposure to pathogens or odors that might be present in manure slurries or sludges. - (i) A buffer zone of one-fourth (¼) mile is required between a land application site and any building with human occupancy or area of public use, not including public roadways.
- (ii) Manure slurries or sludges shall not leave the property where they are applied.
- (iii) Manure slurries or sludges shall not be land applied within 200 feet of a perennial, intermittent, or ephemeral water body or water well permitted for current domestic purposes.
(f) Method of application. - (i) Manure slurries and sludges shall be evenly distributed over application sites at a rate that shall not exceed the agronomic rate and at a rate that shall not result in any surface runoff from the site.
- (ii) Land application of manure slurries and sludges shall not be undertaken when soil is saturated, frozen, or covered with ice or snow or immediately before or during a storm event.
- (iii) Sprinkler type land application systems shall be equipped with a backflow prevention device to protect any water source or well connected to the system. The required level of protection is a reduced-pressure principal backflow prevention device or air gap. All devices must be approved by the Foundation for Cross-Connection Control, University of Southern California.
- (iv) All manure slurries and sludges shall be injected or incorporated within six (6) hours after application.
(g) Metals. Sludges shall not be land applied if the metals concentrations exceed the ceiling pollutant levels established by Chapter 11, Part E, Section 48 of these regulations.
020-20 Wyo. Code R. § 20-38