Pre-Assessment

Why should I be concerned?

Farmers are concerned with soil and water quality. With a rapidly expanding poultry industry and equally rapid urban growth, it is becoming more difficult for farmers to safely dispose of poultry moralities*.

An acceptable system for the disposal of dead birds is essential to any well run poultry operation. Current practices include incineration, burial pits, land filling, digestion/fermentation, rendering and composting. Composting of dead birds is a more recent disposal alternative that is environmentally sound. This process converts dead birds into a humus-like material that can be spread on land for crop utilization and/or soil improvement. This relatively inexpensive method of dead bird disposal is rapidly gaining acceptance in the poultry industry.

Assessment objective

Unlike the other Farm *A*Syst assessments that focus on farmer stewardship and the environmental soundness of facilities and management practices, this assessment focuses on your composting facilities and procedures to ensure that the process prevents health risk or soil and water contamination. This assessment should be used in conjunction with the Broiler or Layer Production Farm *A*Syst assessments that address other environmental concerns pertaining to your operation.

How does this assessment improve the composting facility on my farm?

• This assessment is designed to ensure that your composting facilities, tools and techniques are part of a sound waste management plan.
• If you are a contract farmer, it is recommended that you involve your integrator in this farm assessment. Your company has recommendations on carcass disposal and litter clean-out pertinent to this process.
• Do not make any management changes based on this assessment that may affect your animals without consulting your integrator.
• You are encouraged to complete the entire document.
• The assessment should be conducted by you for your use. If needed, a professional from the Georgia Cooperative Extension or one of the other partnership organizations can provide assistance in completing the assessment.
• You are encouraged to develop an action plan.
• Farm *A*Syst is a voluntary programme.
• No information from this assessment needs to leave your farm.

Assessment

Assessing your poultry mortality composting practices

For each category listed on the left, read across to the right and circle the statement that best describes conditions on your farm. If a category does not apply, for example, if you always spread litter immediately after cleaning out and thus never store litter on your farm, then simply skip the question. Once you have decided on the most appropriate answer, look above the description to find your rank (4, 3, 2 or 1) and enter that number in the 'Rank' column. The entire assessment should take less than 30 minutes.

Assessment Evaluation

What do I do with these rankings?

Step 1: Identify areas that have been determined to be at risk

Low risk practices (4s) are ideal and should be your goal. Low to moderate risk practices (3s) provide reasonable protection. Moderate to high risk practices (2s) provide inadequate protection in many circumstances. High risk practices (1s) are inadequate and pose a high risk for causing environmental, health, economic, or regulatory problems.

High risk practices, rankings of '1' require immediate attention. Some may only require little effort to correct, while others could be major time commitments or costly to modify. These may require planning or prioritizing before you take action. List all activities identified as “high risk” or “1s” in the recommended action plan. Rankings of '2s' should be examined in greater detail to determine the exact level of risk and attention given accordingly.

Step 2: Determine your composting risk ranking

The Composting Risk Ranking evaluates your composting practices for safe environmentally sound disposal of dead birds. It ranks a producer's composting facilities, tools and techniques and identifies areas that may be a risk to a sound water management plan.

Use the ranking total and the total number of areas for your Composting Risk Ranking.

COMPOSTING RISK RANKING .......................LEVEL OF RISK
3.6 to 4 ....................................................................Low Risk
2.6 to 3.5 .................................................................Low to Moderate Risk
1.6 to 2.5 .................................................................Moderate Risk
1.0 to 1.5 .................................................................High Risk

This ranking gives you an idea of how your compost practices might be affecting disease transmission, fire hazards and threats to water resources, as well as the soundness of your waste management plan. This ranking should serve only as a very general guide, and not as a precise diagnosis since it represents the average of many individual rankings.

Step 3: Read the 'Composting Facts' portion of this assessment

While reading, think about how you could modify your practices to address some of your moderate and high risk areas. If you have any questions that are not addressed in the composting facts section of this assessment, consult the references in the back of this publication or contact your county extension agent for some information.

This assessment should be used in conjunction with the Broiler or Layer Production Farm *A*Syst Assessment.

Composting Facts

Composting is a natural, biological process by which organic material is broken down and decomposed because of the bacteria and fungi that digest the organic material and reduce it to a stable humus. The principles of composting are quite simple: just provide the microorganisms with an environment conducive to their growth — a balanced diet, water and oxygen.

In order for composting to be successful as a method of dead bird disposal, the following must take place:

• all birds must be decomposed beyond recognition
• risk from disease transmission must be eliminated
• fire hazards must be minimized
• any threats to water resources must be prevented
• flies must not present a nuisance.

Permitting for poultry mortality composting facilities in Georgia

All methods for the disposal of dead animal carcasses require permits from the Georgia Department of Agriculture (GDA). Growers must submit a written request to the state veterinarian.

The letter requesting the permit should state the name that the producer wants to appear on the certificate of compliance and describe the composting procedures and the type of facility to be used. It must also include the producer's pit number, if he or she has one. If this is a new farm, this should be stated at the time of request.

If the producer plans to have a composting facility inside the poultry house, approval from the poultry contracting company is required. A form is available from the Georgia Poultry Federation.

Interested growers should first contact their local Natural Resources Conservation Service (NRCS) to obtain information on composting and compost facilities.

Composting procedures (or recipes) developed by the Cooperative Extension Service (CES), NRCS, Farm Service Agency (FSA), or the Resource Conservation Development Council (RC&D) must be used.

Composter capacity

In order to meet peak disposal requirements, compost facilities must be properly sized.

Primary bin capacity:

The total minimum volume of the primary bins of composters can be calculated from the expression below:

V = B × (M/T) × W_B × 2.5

• V is the total minimum volume in the primary bin in cubic feet
• B is the total number of birds on the farm
• T is the days of flock life
• W_B is the average market weight of the birds in pounds
• M is the per cent mortality expressed as a decimal (example 5 per cent = 0.05)
• The factor of 2.5 in this equation represents 2.5 cubic feet of composter volume required per pound of dead birds.

Secondary bin capacity:

The total volume of the secondary bins should be the same as the primary composter capacity.

Compost facility design and construction

Roof design

Some materials are composted outside. However, a roof ensures all-weather operation and helps control rain, snow, runoff, and percolations which can be major concerns. In order to prevent excessive moisture in compost, the roof over compost bins must extend sufficiently to protect the compost from blowing rains.

Floor

An impervious (waterproof) floor with a weight bearing foundation (able to withstand the weight and force exerted by farm machinery used in operating the compost facility) is recommended to ensure all-weather operation and to secure the composter against rodents, dogs and other nuisances. An impervious floor also will help dispel questions about contamination of the groundwater and other surrounding areas. A concrete apron, sloped away from the primary bins is recommended. This provides an all-weather surface for equipment and operation.

Fire safety

Temperatures of 140-150°F are often reached in composters within a few days after a bin is capped off with litter. Excessive height and compacting increase the chance that the temperature in the composter will exceed 160°F. Temperatures this high are conducive to spontaneous combustion.

One stacking house in Georgia and at least one other in Virginia burned from spontaneous combustion. Temperatures should be monitored daily and fire extinguishers and water should be readily available to guard against this hazard. If smoldering begins to occur, compost should be removed immediately.

Compost management and operation

The requirements for proper and complete decomposition of dead carcasses are reasonably simple, but proper management is essential. Decomposition of the dead carcasses and litter depends upon microbial activity. The greater the microbial growth, the faster the carcasses decompose. Anything that slows down microbial growth lowers the temperature of the composting material and slows the composting process. The more rapid the microbial growth, the greater the heat output and temperatures of the composting mass and the more rapidly the mass breaks down.

Employee training

All farm workers involved with composting poultry moralities should be trained in composting procedures. Workers lacking training should not be involved in composting dead birds.

Recipe for ingredients that go into compost

The essential elements for the microorganisms involved in composting are carbon (C), nitrogen (N), oxygen (O₂) and moisture (H₂O). If any of these elements are lacking, or if they are not provided in the proper proportion to one another, the microorganisms will not flourish and will not provide adequate heat.

Procedures for composting poultry mortalities

• Start by placing a double layer (usually 8-12 inches) of active litter or litter cake, with 40-60 per cent moisture on the composter floor.
  
  
• This litter will supply bacteria and heat to start the process. This layer will also help in absorbing moisture if excess water is added to the composter. (The base layer should not be placed more than a few days prior to use for composting birds or it will cool as bacterial numbers reduce when moisture or oxygen becomes limited.)
  
  
• Unless litter cake is used which is bulky with much air-holding ability, a thin layer of peanut hulls, coarse shavings or straw is added next.
  
  
• A layer of dead bird carcasses is then added. The carcasses should be arranged in a single layer side by side, touching each other. Carcasses should be placed no closer than six inches from the walls of the composter. Carcasses placed too near the walls will not compost as rapidly, since the temperature is cooler near the walls.
  
  
• A layer of litter cake (40 to 60 per cent moisture content) twice as thick as the layer of carcasses underneath or litter (1.5 parts by weight) is added next. This layer should be twice as thick as the layer of carcasses underneath.
  
  
• If only a partial layer is needed for a day's mortality, the portion should be covered with litter. The rest of that layer can be used with subsequent mortality.
  
  
• A small amount of water may be needed after each layer. If much water is required, the litter is too dry and probably low in live bacteria.
  
  
• After completing the initial layer, subsequent layers of either litter cake and carcasses or litter, bulking ingredients and carcasses follow. Keep adding layers until compost height approaches 4 to 4½ feet. Do not exceed 5 feet.
  
  
• Cap off with a double layer of litter so that the height of compost in the bin does not exceed 5 feet. Excessive height increases the chance that the composter temperature will exceed 160°F which increases the risk of spontaneous combustion.

Figure 1. Composter bin

Table 3. Carbon:nitrogen ratio
Ingredient	C:N Ratio
Birds	5:1
Litter	7:1 to 25:1
Straw	80:1
Peanut hulls	50:1
Shavings	300-700:1

If two parts by volume of litter, one volume of dead birds, and adequate bulking agent is either contained in the litter, or added prior to the carcasses, the C:N ratio should be adequate. If moisture and aeration are adequate, materials with lower C:N ratios usually compost at higher temperatures.

Microorganisms

Starter:

The microorganisms responsible for composting are initially supplied by active litter or litter cake. The microbes in the litter used in the composting process need to be kept alive and in sufficient numbers so that composting can begin immediately to break down the carcasses and the litter. Litter that is too dry and too long removed from the house will contain very low numbers of microorganisms. Old and dry litter that contains low numbers of the necessary microorganisms slows the process of carcass decomposition.

Re-activating litter:

Litter that is too dry or old should be activated before it is used in the composting process. A quantity of litter to be used in the next week can be reactivated by raising the moisture content up to 40-60 per cent. Excessive moisture displaces the oxygen, which reduces the heating and causes seepage.

Moisture is critical. If the moisture level is correct, the microorganisms in the pile will again begin multiplying, raising the temperature of the litter. When hot (130-150°F), the litter is ready for use in decomposing carcasses.

Moisture content:

Water is essential to the growth of any living organism. Composting microorganisms thrive in moist but not soggy conditions. Desirable moisture content in the composting materials is between 40 and 60 per cent. Excessive moisture displaces the oxygen, which reduces the heating and causes seepage. Too little will prevent microorganisms from reproducing to adequately high numbers.

Compost moisture can be accurately measured with a moisture meter. However, moisture content can be estimated by hand. The moisture content of litter used for starter or compost is about right, if when it is squeezed with the hand, it breaks into to three large pieces when the hand is opened. If water can be squeezed from the material, the moisture content is too high.

Temperature

Composting begins as soon as the loading begins. Depending on the size of the primary cell and the number and size of carcasses, the loading time will vary. With active litter, a week's loading time may allow the lower levels to rise to 150°F by the time the cell is capped. A probe type thermometer is used daily to measure and plot temperatures 8-10 inches into the center of the compost pile.

Destroying pathogens:

While three consecutive days at 130°F or more in the composter is adequate to destroy pathogens harmful to man and poultry, composting in the primary bin normally occurs over a 10- to 21-day period.

Monitoring temperatures:

Measure and record temperatures in each bin daily to ensure that dead birds have been pasteurized, to minimize the risk of spontaneous combustion and to determine when to turn the compost.

When oxygen becomes limited, the temperature of the compost begins falling. By the time it drops to 130°F - about 7-21 days after capping - the compost can be moved to a secondary cell. At a temperature of 150°F, the birds decompose about twice as fast as at 130°F. If the temperature of the compost reaches only 130°F, birds nearer the walls, where it is cooler, will decompose very slowly.

Bulking agents:

The composting product can be sustained at higher temperatures by using a bulking agent which makes the compost pile more porous and thus supplies more oxygen to the composting process. A coarse material, such as wood shavings, straw or peanut hulls will ensure more oxygen, allowing higher composting temperatures. Also, adding more litter or litter cake increases heating. If litter cake is used, little or no bulking agents are needed.

Compaction and stack height:

Do not compact litter in deep layers and do not stack your compost higher than five feet. Temperatures of 140-150°F are often reached in composters within a few days after a bin is capped off with litter. Excessive height and compaction will increase the chance that the temperature in the composter will exceed 160°F. Temperatures this high are conducive to spontaneous combustion.

Aeration and moving compost to second cell

The purpose of moving the product is to re-mix and aerate it so that a faster, more complete break-down of the compost occurs. Allow material to 'cascade' from the loader bucket to provide good turning and re-aeration as it is deposited in the secondary treatment area. The movement to a second cell will probably be necessary to get adequate decomposition if the birds exceed 4-5 pounds or if material is removed from below and added above (see package composters).

The product temperature should again rise to 150°F within days. Delayed movement, poor aeration, poor mixing or moisture above 60 per cent or below 40 per cent will cause the mass not to heat properly.

Once the temperatures (determined by daily monitoring) drops from 150°F to 130°F (7-21 days), the product is ready to be used as a fertilizer.

Flies and odour

Flies and odour are not a problem where composters are operating properly. The heat destroys the habitat for flies and since the process is aerobic (in the presence of oxygen), very little odour is produced. Improved management is usually the best solution to odour and fly problems.

Composter types and lay-outs

Composters presently used for dead birds consist of four types.

Figure 2. Package composter

Figure 3. Small bin composter - plan view

Figure 4. Big bin composter - plan view

Figure 5. Mini-composter

• Package composters: (Figure 2) These composters are commercially available. The composted by-products fall to the bottom of the composter down to the concrete slab where they are then shovelled by hand back to the top to compost new dead birds. A five-gallon bucket of new litter material is normally added to each composter each week. A few operators will add a small amount of bulking agent such as peanut hulls or cotton seed to trap oxygen and promote heating.
  
  
• Delmarva (small bin): (Figure 3) The front wall of the bins consists of two-inch thick boards which are mobile to help with filling and removing the material to be composted. The material in the composters is moved with some type of end loader or skid steer loader. Therefore, the width of the small bin composter must allow the loader bucket to get into the bin.
  
  Normally these small bin composters are 8-10 feet wide by five feet high and five feet deep. The depth is limited to five feet due to the reach required to drop the composted material into the secondary bin, which is immediately behind the primary or small bin. Moving the material from the primary bin to the secondary bin after 10 to 21 days is common for Delmarva-type composters to mix in oxygen in the mass to promote heating. The oxygen is added as the mixture is dropped or moved from the primary bin to the secondary bin.
  
  
• Big bin (adaptation of the Delmarva): (Figure 4) The big bin uses a primary bin which does not have a removable front. In fact, the front is totally open and the compost material slopes back slightly with the front face of the composted material standing at an angle of about 70-75°. The front face of the pile must slope back slightly because the material will not stand on a vertical angle since no front wall is present for support. Many larger growers prefer the big bin composters. The big bin type composter is normally 10-12 feet wide and 20- 50 feet or more in length. The primary and secondary bin are usually side by side or parallel to each other and built like a bunker silo. The big bin composter, like the small bin type, is filled to a height of five feet.
  
  
• Mini-composter: (Figure 5) The mini-composter is a type of composter which can be used inside the broiler house for the disposal of birds up to about five to six pounds. These may be as simple as four pallets tied together at the corners and lined with wire mesh to make a cubicle.

Land application

Poultry mortality compost is a nutrient-rich material. This material can benefit the farm if it is adequately protected and correctly land-applied. However, storage and application of this nutrient rich material can be a threat to farm water sources if not done properly.

Stored compost should be sampled and tested to determine its nitrogen, phosphorus and potassium content. These nutrient values, combined with the amount of litter or residue applied per acre, allow for determination of whether more commercial fertilizer should be added to meet realistic crop production goals.

A Nutrient Management Plan (NMP) assists you in effectively using poultry mortality compost in an environmentally safe manner. Any situation where compost or animal waste is not effectively managed gives rise to potential pollution. Nitrogen in poultry mortality compost can be converted into the nitrate that can cause methemoglobinemia (blue baby syndrome) in infant humans and livestock. The phosphorus contained in compost can cause algal blooms and increase the rate of eutrophication in surface waters.

A sound nutrient management plan begins with the type and number of animals in the farm operation and includes every aspect of waste handling. It includes how the waste will be gathered and stored including how large the storage facilities need to be. It also specifies areas to be used for manure applications, crops to be grown, the area of land needed to utilize available nutrients and the method of timing of application.

The NMP should identify the locations, acreage and types of crops or pasture to which any wastes are to be applied. An owner may have plenty of land for application of animal wastes, but some of it may be located a great distance from the poultry houses. The practice of spreading dead animal compost only on the nearest fields can result in excessive nutrient-loading rates to the soil and possibly cause water quality problems.

Dead bird compost application

Application rates, calibration and timing, and record keeping should be handled like manure. The Georgia Cooperative Extension Service, NRCS county offices and Georgia Department of Agriculture (GDA) can provide information on composting as well as other disposal methods. Compost should go through at least two decomposing cycles (primary and secondary treatment) before being land applied.

Soil testing of application sites

Compost can be sampled and tested to determine the nitrogen, phosphorus and potassium content. These nutrient values combined with values for manures, crop residues and starter fertilizer help determine whether more commercial fertilizer should be added for desired crop production.

All land applications of poultry mortality compost should be based on soil test, compost analysis and realistic crop yield goals.

Record keeping

Keep records of the dates, quantity and specific application sites. If you sell the litter, keep a record of buyers, dates, amounts and the farm sites where buyers apply or use the litter. These records can assist you with management and protect you from liability.

Application rates

The best application rate depends on the crop being produced, the soil's nutrient content and the nutrient content of the applied material. Soil testing and litter nutrient analyses are recommended procedures for best determining litter application amounts. Application equipment should be calibrated for accurate and even distribution.

Poultry compost should be evenly distributed over application sites at a rate determined and listed in your nutrient management plan.

Vehicles must be covered or tarped for transporting poultry compost on state or federally maintained roads or any public road.

Your county extension office can provide more information on soil testing, litter analyses, equipment calibration, record keeping and other areas related to poultry compost land application.

Application timing

Surface land application of poultry manure and compost residue should not be undertaken when soil is saturated, during rainy weather or when rain is in the immediate forecast.

Application areas

Consider unique features of the farm and make your management plan specific for these features. Do not apply poultry compost to the surface and subsurface within 100 feet of streams, ponds, lakes, springs, sink-holes, wells, water supplies or dwellings. Grass, vegetation and/or forest buffer strips along stream, pond or lake banks are helpful in preventing nutrient runoff from adjacent fields and pastures.

Do not apply nutrients on slopes with a grade more than 15 per cent or in any manner that will allow nutrients to enter the waters of the state.

Calibrating

Calibration of waste application equipment, such as irrigation systems, tank wagons and manure spreaders is needed to ensure safe and efficient distribution of waste materials. Equipment should be calibrated and rechecked at least once during the application period since the consistency of the composts can vary greatly. For more information about calibration of waste-spreading equipment, contact your county Extension office.

Glossary:

Aerobic: In the presence of oxygen or air

Cake litter: Clumps or larger pieces of poultry manure and bedding that are removed from the litter surface using a de-caking machine. Cake usually results from the presence of excessive moisture.

Compost: Organic residues that have been collected and allowed to decompose.

Composting: A controlled process of decomposing organic matter by microorganisms.

Cost Sharing: A programme in which Consolidated Farm Service Agency (formerly the Agricultural Stabilization and Conservation Service) pays a percentage of the costs of a project, facility or effort.

Decomposition: The break-down of organic materials.

Eutrophication: The process by which increasing nutrients in a water body promotes plant over animal life, often creating conditions with very low oxygen in the water.

Impervious: Incapable of being penetrated by water or other liquids.

Leaching: The removal of soluble substances from soils or other material by water.

Litter: A mixture of poultry manure and bedding material.

Mortality: Birds that died during production.

Nutrients: Elements necessary for plant growth, such as nitrogen (N), phosphorus (P) and potassium (K).

Nutrient Management Plan: A specific plan designed to manage animal manures and moralities so that the most benefit is obtained and the environment is protected.

Stack house (shed): A structure designed and built for the storage of poultry manure or compost.