Update on Swine Mortality Disposal in Virginia
Livestock Update, February 2005
Dr. Allen Harper Extension Animal Scientist, Swine Tidewater AREC, VA Tech
Mortality disposal is a routine part of operating any hog farm. But, unlike other components of hog farm management, doing a good job with mortality disposal does not directly influence financial returns to the operation. Actually, mortality disposal is a cost center, rather than a profit center for the operation. Despite this fact, mortality disposal is critically important to the long term success of the operation. Poorly managed disposal of dead hogs can result in:
The purpose of this brief paper is to give a current update on methods of routine mortality disposal on Virginia hog farms. Four principle methods will be addressed: burial, incineration, rendering and composting.
Over the years burial has been the traditional method of disposing of dead hogs and other livestock on farms. A very old statute in the State Code of Virginia (Code 1950, item 18.2-510) mentions burial of livestock directly. This law states that "when the owner of any animal or grown fowl which has died knows of such death, such owner shall forthwith have its body cremated or buried." A backhoe or similar mechanical equipment is necessary for labor efficient on-farm burial. Suggested recommendations for proper burial include choosing a site that does not place dead animals near the seasonal high groundwater table and away from other sensitive areas such as wells, ditches and streams. Dead stock should be fully covered at the time of burial with compacted soil of adequate depth to prevent scavenging. Collection of rain and run-off water in and around burial pits should be prevented.
In recent years, a Virginia state law was passed that bans the use of burial pits for dead bird disposal on poultry farms; and currently, there is some misunderstanding among producers and regulators regarding the legality of on-farm burial as a means for disposing of dead hogs and other livestock. The old law from the 1950 State Code does not acknowledge that burial of waste materials is now regulated by the Virginia Department of Environmental Quality (DEQ). Regulations administered by DEQ indicate that burial of solid waste, including animals, requires a permit. Furthermore, DEQ recommends that burial of dead stock should take place only as a last resort and primarily in cases where the spread of animal disease is a concern as determined by the State Veterinarian.
This creates a difficult situation for Virginia producers who rely on burial as their primary method of mortality disposal. Permits issued for on-farm burial are currently rare, but this could change. Furthermore, the fact that burial is no longer allowed for dead poultry disposal suggests that similar laws or regulations for other livestock are likely in the near future. Under these circumstances, implementing alternative methods of mortality disposal would be the proactive strategy for farms currently using burial.
On-Farm Incineration (Cremation)
Using fuel-assisted incineration equipment to cremate dead stock has distinct advantages. Prompt on-farm incineration is bio-secure. It gets dead stock out of public view and reduces potential for attraction of scavengers and flies. Modern incineration equipment can reduce carcasses to inert ash. If properly maintained, the equipment is easy to operate and does not have excessive labor requirements. The dead stock is simply loaded into the incinerator and the controls are set for complete burning. Only periodic observation, routine maintenance and clean-out of ash are required.
Cost of incineration equipment varies among different manufacturers and with incinerator capacity and operational features. One supplier of a standard 700 lb. load capacity model quotes a list price of $5,492. A similar 1,200 lb. load capacity model was quoted at $7,297. For either of these incinerators a direct fired secondary burn chamber (afterburner) can be added for $1,997. A second supplier lists a larger 1,500 lb. capacity unit with a secondary burn chamber included at $15,000. None of these prices include freight to ship the units to the farm nor do they include costs for hook-up to the fuel source.
Operating costs for incineration is determined mainly by fuel price and use. Modern units equipped with thermostatic controls are more fuel efficient. One manufacturer estimates current fuel costs of $0.0125 to $0.015 per lb. of mortality cremated and approximately 40% additional fuel cost if an afterburner is used. A University of Nebraska publication estimates fuel consumption rate at 1 gallon per 78 lbs. of mortality and 1.35 gallons if the unit is equipped with an afterburner. Assuming a fuel cost of $1.90 per gallon, this estimate equates to fuel operating cost of $0.024 per lb. of mortality and $0.033 if an afterburner is used.
For Virginia producers, the most important consideration with mortality incineration may be the regulatory requirements. Under current regulations, operation of an on-farm incinerator for livestock mortality disposal requires a permit from the DEQ air board division. This permit is separate from and in addition to any permits currently in place for manure management. Furthermore, the regulation stipulates that the incineration equipment permitted must include "best available control technology" for reduced air emissions. This stipulates that the incinerator must be equipped with a secondary burn chamber or afterburner. These additional equipment requirements increase both initial investment and operational costs. Ironically (and some would say unfairly), several years ago an exemption which removed the DEQ permit and afterburner requirements was granted for operation of mortality incinerators on poultry farms.
The process of applying for a permit is handled through the regional DEQ office that serves the applying farm. There are seven regional DEQ offices as summarized in the following table.
|Regional DEQ Office||Office Location||Main Telephone Number|
|West Central||Roanoke||(540) 562-6700|
|South Central||Lynchburg||(434) 582-5120|
|Piedmont||Glen Allen||(804) 527-5020|
|Tidewater||Virginia Beach||(757) 518-2000|
Producers planning to implement incineration for mortality disposal should initiate the permitting process with the regional DEQ office before investing in incinerator equipment. This is critical because DEQ must approve the operational specifications of the incinerator to be permitted. The obvious risk with purchasing before the permit is issued is that the equipment may not meet required DEQ specifications.
Transport to Rendering Plants
Commercial rendering plants are in operation to convert by-products of livestock, meat and food processing industries into useful by-products that can be used in pet foods and animal feeds. An obvious advantage of rendering to dispose of livestock and poultry mortality is that an unusable product may be converted to a product that has use and value. And, once dead stock is removed from the hog farm to the rendering plant, it is no longer a potential liability or management concern for the farm.
Unfortunately the number of rendering plants operating in Virginia is limited. In many cases hog farms are located too far from a plant for rendering to be a viable option. Producers who do have the option of hauling dead stock to a rendering plant are now faced with the reality that fees may be charged to accept dead stock. This is in contrast to past conditions in which farmers actually received nominal payment for dead stock delivered to a renderer. One regional rendering plant quotes a fee to the producer for delivered hogs of $10 minimum for anything less than and up to the first 1000 lbs. plus $0.01 per lb. for everything over 1000 lbs. Such fees are common in rendering plants that handle various species of dead stock. This is in part due to the reduced market value of meat and bone meal products from mixed species rendering plants. This market situation is directly related to recent feed industry regulations restricting use of meat and bone meals derived from ruminant animals. For producers who are willing to incur fees and deliver dead hogs to the plant, extreme care must be taken to maintain bio-security and avoid potential disease transfer from the plant back to the farm.
Ultimately transport for rendering is a viable alternative only for hog farms located close enough to a plant such that the contracting integrator or a rendering service will make routine pick-up of "deads." Even under these circumstances care must be taken to properly locate and manage metal "dead boxes" so that bio-security is maintained and excess fly and odor problems are not created.
On-Farm Mortality Composting
Mortality composting was originally developed as a means of disposing of dead birds on poultry farms. Over the past ten years, composting has also been developed as a method of disposing of hogs and other livestock. When performed properly, composting converts dead swine into components of an organic residue that can be used as a soil amendment and fertilizer. If properly constructed and managed, composting units present minimal risk for air, soil or water contamination. Regulatory consultants at DEQ have indicated that, when it is performed properly, composting to dispose of routine swine farm mortality is exempt from permit requirements under an agricultural exemption. Virginia Cooperative Extension Publication 414-020, Composting for Mortality Disposal on Hog Farms, provides complete guidelines for effective mortality composting.
When composting swine mortality, the dead hogs, which are nitrogen-rich, are fully covered with and allowed to react with carbon-rich bulking materials such as sawdust, cotton gin trash, chopped corn stalks or other similar material. Naturally occurring bacteria in the mixture then cause the conversion of these components into humic acids, bacterial biomass and compost. During the process, carbon dioxide, water vapor and heat are generated. In mortality composting, it is essential that each carcass be fully surrounded and covered with bulking material to allow for complete interaction of carbon- and nitrogen-rich materials and to absorb moisture and odors released by the carcasses. The bulking material also serves as an insulator to retain the heat and moisture that is generated during the composting process.
As with effective burial and incineration, efficient composting requires some equipment and facilities. A small tractor equipped with a front-end loader or skid-steer loader is necessary to move carcasses, handle bulking material and place and cover carcasses in compost piles. Loader equipment is also needed for turning compost piles and loading mature compost for hauling and spreading.
If properly located it is feasible to safely perform mortality composting in exposed piles on compacted earth. Round hay bales have been used to form three-sided enclosures for this method of mortality composting. However, the best managed compost units are those that have a dedicated structure with constructed bins that hold static piles of mortality compost in various stages of maturity. These permanent multi-bin structures are typically constructed on concrete surfaces to facilitate scooping, moving and turning of the material. Plumbing a water source to the compost unit is helpful to allow efficient application of water to the compost piles when necessary.
The initial capital cost of a composting facility varies with the type and size of structure built and labor costs associated with construction. The University of Nebraska mortality disposal publication estimates the cost of a 7-bin (10¹ x 14¹ bins) with a mono-slope roof and concrete floor and apron at $15,200. This size unit would meet the needs of a farm that produces about 40,000 lbs. of mortality annually. This same publication estimates the average labor requirements to operate the unit at about 2.2 hours per week compared to about 1.2 hours per week for incineration.
Under the current USDA Farm Bill, an Environmental Quality Incentives Program (EQIP) is in place that provides funding to initiate management practices that improve soil and water protection on farms. The EQIP program is administered through the Natural Resources Conservation Service (NRCS). In Virginia it has been determined that construction of a swine mortality composting unit can be considered for EQIP cost-share funding. It is important to recognize that the facility design must meet USDA-NRCS specifications and must be approved by engineers in that agency. If approved at the local and state level, cost-share amounts of up to 75% may be available. It should also be understood that not all EQIP applications are funded and those deemed to have the greatest environmental protection impact in a given region are given priority.
Another incentive program available to Virginia producers considering implementation of mortality composting includes a low-interest loan program administered by the Virginia Department of Environmental Quality (contact : Van M. Gallier, DEQ central office, 804-698-4243). Currently state cost-share funding opportunities for mortality composting are more limited. The Virginia Department of Conservation and Recreation (DCR) does offer a best management practice (BMP) cost-share opportunity for poultry mortality composting, but the agency has not approved this opportunity for swine or other livestock. However, a tax credit incentive program is available.
Proper mortality disposal is an essential component to the long-term sustainability of any hog farm. In Virginia four typical methods are available: burial, incineration, rendering and composting. Under current conditions considering environmental protection, regulatory requirements, farm bio-security and economics, it appears that on-farm incineration and composting are the most viable alternatives for most producers in Virginia. One exception may be transport for rendering in situations where farms are in close proximity to a rendering plant and rendering trucks can be sent to the farm for mortality pick-up on a routine basis at reasonable cost. Each method will require proper equipment and management to be safe and effective. Each producer should carefully assess their own farm situation to determine the best mortality disposal system for their operation.
Harper, A.F., and M.J. Estienne. 2003. Composting for Mortality disposal on hog farms. Virginia Cooperative Extension publication 414-020, Virginia Tech, Blacksburg, VA.
Henry, C., R. Wills, and L. Bitney. 2001. Disposal methods of livestock mortality. Nebraska Cooperative Extension publication G01-1421-A. University of Nebraska, Lincoln, NE.