Anaerobic Digestion

A biological process that occurs in the absense of oxygen. In very large animal production operation, it is sometimes used to produce biogas (a low energy gas which is a combination of methane and carbon dioxide) from the biodegradable organic portion of manure. This gas can be used as an energy source. After anaerobic digestion, the remaining semi-solid (which is relatively odor free but still contains most of its nutrients) can be used as a fertilizer.

AMANURE Computer Program FBPS

Available online at: http://danpatch.ecn.purdue.edu/~epados/amanure/frame.html

Cause a wide variety of conditions such as gastroenteritis, hepatitis, and typhoid and may be contained in manure that enters drinking water sources. Such water-borne diseases are relatively rare in the United States today due to advanced water treatment methods in use; however, contaminated wells which are not disinfected could be hazardous to health.

Bedding, such as straw, sawdust, wood chips or wood shavings, shredded newspaper, sand or chopped cornstalks, is used for the comfort of the animal or added to absorb excess moisture. The amount of bedding to be added must be taken into consideration in the design of the manure storage facility.

Some manure handling and storage systems require that manure be a consistency that can be stacked into a pile and does not flow. To produce this consistency, bedding material is added to the manure. The moisture content of the bedding determines the amount of bedding needed. The drier the bedding material, the less will be needed.

Earthen berms should be protected, where allowed by state regulations, by emergency spillways. These can prevent potentially catastrophic failures from overflows and erosion that could occur in the event of rainfall events that exceed design storms. This is especially important if the storage receives runoff from a large drainage area such as an open feedlot.

An illness that begins when large amounts of nitrates in water are ingested by an infant and converted to nitrite by the digestive system. The nitrite then reacts with their oxygen-carrying blood protein to form metheglobin, which cannot carry oxygen. If a large enough amount of metheglobin is formed in the blood, body tissues may be deprived of oxygen, causing the infant to develop a blue coloration of their mucous membranes and possibly digestive and respiratory problems. This "blue baby syndrome" is most common in rural areas where higher amounts of nitrate-contaminated water is found in wells. This condition is also known as methemoglobinemia.

A standard test to assess wastewater strength. It is a measurement of the oxygen used during the biochemical oxidation of organic matter over a five day period at a temperature of 68 degrees Fahrenheit.

A concrete or post-and-plank wall which a front-end loader may "buck" against while loading the manure.

A complex carbohydrate of the cell walls of plants. Ruminants can digest cellulose since they have the appropriate bacteria in their stomachs.

A technique by which the depth of a lagoon is constructed by excavation and by filling in, so that the basin is partially above and partially below ground. This reduces the potential for leaching of effluent into high water tables, but the higher berms must be more carefully constructed to ensure structural integrity.

Sometimes it is necessary to add water to the manure in order to get it to the appropriate solids content for handling. This can be accomplished in a number of ways such as by adding milking center wastewater, flush water, rainwater, or overflow water to the manure. See "Livestock Waste Facilities Handbook", 2nd edition, MWPS-18, to determine the amount of dilution water needed for a particular situation.

If livestock are allowed access to streams or ponds, they will deposit manure directly into the water. Fence off areas of surface water to avoid contamination. Federal law requires farmers to obtain a discharge permit if their livestock production operation has a discharge, or even a potential discharge, of manure or polluted runoff and if their feedlot holds more than 1,000 animal units for thirty or more days during the year.

 

1,000 Animal Units Represents the number of various livestock species required to produce the amount of manure that 1,000 head of beef cattle would produce. The following numbers of animals equal 1,000 animal units:

• 1,000 beef cattle
• 2,500 hogs over 55 pounds
• 700 dairy cows and pregnant heifers
• 10,000 sheep
• 55,000 turkeys
• 30,000 layers or broilers with liquid manure handling
• 100,000 layers or broilers with a continuous overflow watering system.

Represents the portion of solids which will not settle out of liquid, but remain in solution.

Controls the flow of uncontaminated rainwater and snowmelt, directing it around areas where the runoff could be contaminated by manure , such as around feedlots and manure stacks. If dilution water is needed, regulated amounts of uncontaminated water can be allowed to enter and remain in the storage areas while the remaining portion should be diverted away from all livestock facilities.

Some solid and semi-solid storages are designed to drain the liquids away from the storage. Since manure, over time, will seal along the walls and floor, vertical drainage is provided along the walls of a solid manure storage. A six-inch layer of land-disposable porous media, such as corn cobs, is placed on the floor under the manure to allow for horizontal flow to the floor drains. Gutters or floor drains with underground pipes may be used to the collect the drainage and direct it to a water-tight storage. In some states, the drainage may be diverted to a grass infiltration area. Check with state authorities for restrictions. Other possibilities are to build a roof over the storage to eliminate the addition of extra water or add large amounts of bedding in order to absorb any additional water.

A shallow notch in the lagoon sidewall to allow lagoon overflow to spill over into a secondary containment or into a grass infiltration area in case of emergencies such as unexpectedly large rainfall event. The spillway should be designed and constucted under the supervision of a registered professional engineer or the NRCS and must be diverted away from water courses. While overflow should be avoided if at all possible, failure to provide a planned overflow in case of rainfall events that exceed design values risks berm failure that can result in a catastrophic pollution situation.

The reserve volume designed into a lagoon or earthen manure storage to minimize chances of the contents overflowing and causing contamination. Freeboard is typically sized to hold the water draining into the storage from the highest intensity 24-hour rainfall expected to occur within 25 years.

A disorder of the digestive tract stemming from the presence of bacteria in drinking water.

The water under the surface of the earth that is found within the pore spaces and cracks between particles of soil, sand, gravel, and bedrock.

An acute disease featuring inflammation of the liver.

High water tables present special concerns. If the seasonal high water table is within three or four feet of the bottom of the manure storage, consider using drain tile to control the level of the water table around the storage and to intercept seepage from the storage. Most states have specific construction requirements when building earthen manure structures.

May be a long, grassed, gently sloping channel or a broad, flat area with little or no slope surrounded by a dike. It helps to clean up contaminants in runoff water by slowing the runoff so that it can gradually infiltrate into the soil. A thick, healthy stand of vegetation is required so that the would-be contaminants are taken up as nutrients by the grasses. Use settling basins to remore most of the solids before the runoff enters the infiltration area. Lagoon effluent is not allowed to overflow in most states, except in the event of an extrordinarily large rainfail even, because it has a high concentration of nutrients and salts that can not burn the vegetation in the infiltration area. Runoff should not be applied at a nutrient-loading rate which is higher than the grass can utilize. Check with local regulatory agencies since infiltration areas are not permitted in all states.

Typically constructed of 8 to 12 inch plastic or concrete sewer pipe.

An irregular limestone region with sinks, underground streams, and caverns. (The Merriam-Webster Dictionary) Karst areas can provide direct channels for contaminants to reach the groundwater.

As water comes into contact with manure, nitrates and other soluble components in the manure may be dissolved into the water. The water may then carry these soluble constituents along with it as it infiltrates into the soil and moves down into the groundwater. Soils that have high water tables and rapid water percolation rates are more likely to allow contaminated water to reach the groundwater. Be careful not to store manure directly on these types of soil, and do not overapply manure to such fields.

The loss of water-tightness due to a hole, crack, or improperly sealed joint.

Portion of the Farmstead Assessment Educational Package which covers manure management for various livestock housing facilities, including the handling of feedlot runoff. The program is also available on CD ROM from the Agricultural Engineering Department, Purdue University, West Lafayette, IN 47907 (765-494-1174).

The location of manure storages is crucial in preventing manure seepage from reaching the groundwater. Important considerations include:

• Permeability of the soil surrounding the storage
• Depth to the water table
• Amount of limestone and gravel present

Impermeable soils with low water tables and no limestone or gravel present will allow fewer contaminants to reach the groundwater.

By-products from livestock production including animal excrement, bedding, wash water, spilled feed, cleansers, and hair.

Consult your state envrironmental regulatory agency, Cooperative Extension Service (CES) or the Natural Resource Conservation Service (NRCS) for manure application rates to avoid groundwater pollution.

Can be used to dilute manure. For more information, see the "Milking Center Wastewater" program of the Farmstead Assessment Educational Package. It discusses the risks associated with milking center wastewater and proper ways to handle and dispose of the wastewater. It is also available on CD ROM from the Agricultural Engineering Department, Purdue University, West Lafayette, IN 47907 (765-494-1174).

Nitrates are a major concern, with regard to manure contamination of drinking water, since nitrates can cause a health problem known as blue baby syndrome in infants under six months of age and a similar condition in young livestock. Nitrates may also affect adults, but the symptoms are less certain.

FACT: Wisconsin's Department of Natural Resources estimates that 10% of the state's wells exceed the federal drinking water standard of 10 ppm of nitrates; that is approximately 70,000 contaminated wells in Wisconsin alone. Similar results have been found in other Midwestern states.

SOURCE: Nutrient and Pesticide Best Management Practices for Wisconsin Farms.

NOTE: Commercial fertilizers are also a potential source of nitrates in groundwater.

Have the potential for surface water pollution if the livestock feeding and watering area is near surface water. Manure can also be directly deposited into the water by the animals if they have direct access to the stream. An additional problem associated with steam access is that stream banks are often broken down due to the animal traffic, resulting soil erosion.

Permeability is a measure of how readily liquids can pass through a soil. Silt loams and sandy loam soils are relatively permeable. An impermeable soil is one which does not allow liquids to pass through easily. Clay loams and loams are relatively impermeable. Manure storages should be located over IMPERMEABLE soils so that seepage will not pass down through the soil into the groundwater.

Can enter lakes, streams, and other sources of surface water through runoff when manure is surface applied in close proximity to them. Phosphorus is tightly held in most soils and does not leach in significant quantities, but soils do have a limit as to the amount of phosphorus they can absorb and retain. If this amount is exceeded, the excess phosphorus will leach and can contaminate groundwater and eventually surface water. The chances of phosphorus leaching increases with long-term overapplication of manure or the application on sandy soils with low organic matter content or on soils with high water tables. However, most phosphorus entering surface water comes from direct runoff and from runoff in the form of soil erosion.

A structure which holds manure solids back but allows liquids to drain through, regardless of the manure level. It is constructed with continuous vertical slots about 3/4" wide between standing planks, or pickets. Picket dams are needed anywhere rainwater might accumulate.

Hoofed animals with four-chambered stomachs (i.e. cattle, sheep, goats). Ruminants have a complex digestive system with a complex biological system that is capable of generating much of their own protein needs.

Surface water that flows downslope across the surface of the soil until it reaches a collection area such as a puddle, pond, lake or stream. If the flowing water comes into contact with manure on its way, it may carry nitrates, manure solids, bacterial organisms, and other contaminants with it. Runoff can also reach the groundwater directly through: sink holes, karst areas, and improperly cased wells. Feedlots are designed with a slope so that water will flow off. This contaminated water should be collected and stored or properly disposed of in order to protect water supplies. Divert upslope uncontaminated water away from the feedlot so that it will not become contaminated. To find out more about feedlot runoff, see the Livestock Yards Management program of the Farmstead Assessment Educational Package.

Liquid which moves slowly down through cracks, pores, and interstices of the soil. Leaky manure storages may allow manure to seep through the soil to the groundwater. Earthen basins and lagoons almost always have some seepage and, thus, should be lined carefully constructed to minimize seepage of manure into the soil. Seepage rates are usually expressed as flow volume per unit time.

A hollow in a limestone region that connects with a cave. (The Merriam-Webster Dictionary) Sink holes provide a direct channel for contaminants to reach the groundwater.

Loading large amounts of manure infrequently into a lagoon. Slug loading upsets the biological balance in a treatment lagoon and causes a rapid increase in volatile acids, lowers the pH, and increases odors. If slug-loading is unavoidable, consider a holding tank that can be slug-loaded and emptied gradually into the lagoon. For best treatment, lagoons should be loaded either continuously or weekly with smaller amounts of manure. In addition, manure added to a treatment lagoon must be properly diluted to ensure proper treatment.

Manure helps to improve soil tilth, increases water holding capacity, lessens wind and water erosion, improves aeration, and promotes beneficial organisms in the soil.

The total solids content in a liquid is the sum of the dissolved and suspended constituents.

The water on the surface of the earth such as streams, lakes, and ponds. It also includes ponded rainwater and snowmelt which may run down sloped land.

Represents the portion of solids which are suspended but will eventually settle due to gravity and to biological and chemical flocculation. Suspended solids are important since they determine the type of equipment needed to handle the manure and to evaluate the efficiency of treatment units.

A communicable bacterial disease marked by fever, diarrhea, prostration, and intestinal inflammation.

A.L. Sutton and D.D. Jones. ID-101. Available from: Media Distribution Center, Purdue University, West Lafayette, IN 47907.

Occurs when a substance vaporizes into the atmosphere at a relatively low temperature.

The very top of the zone of saturation, or the level of underground water. Although some water can be found a few centimeters above this level due to capillary action, almost all groundwater is at or below this level. The water table can rise or fall, depending on rainfall, evaporation, or pumping action. High water tables can be a problem since surface contaminants do not have as far to travel to reach the groundwater and are therefore not filtered as well. Perched water tables are normally small pockets of ground water located above a limiting layer that does not permit the water to proceed on down to the ground water.

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