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99 4 Manure Storage Cattle produce nearly 1 billion tons of organic waste each year. The average feedlot steer produces more than 47 pounds of manure every twenty-four hours. Nearly 500,000 pounds of manure are produced daily on a standard 10,000-head feedlot. This is the rough equivalent of what a city of 110,000 would produce in human waste. There are 42,000 feedlots in 13 U.S. states. (Ensminger, 1991, p. 187) 4.1 INTRODUCTION Manure and wastewater storage and handling needs are highly specic to the condition and location of each facility, and they differ from farm to farm. The capability to store manure reduces or elimi - nates the need to collect, remove, and spread manure frequently and gives the producer control over when manure must be removed and applied to land—manure nutrients are best used when applied just before or during the growing season of the crop. Simply, according to NWPS 18-1, Section 2 (2001), “the primary reason to store manure is to allow the producer to land apply the manure at a time that is compatible with the climatic and cropping characteristics of the land receiving the manure and the producer’s time availability…the type of crop and method of manure application are important considerations in planning manure storage facilities” (p. 1). As livestock operations have increased in size and manure management systems have evolved from solid and semisolid systems to liquid systems, the need for storage has become more pronounced. Important point: Land application during periods of saturated, wet, frozen, or snow-cov- ered soil conditions is not recommended and is prohibited in some states. Manure and wastewater storage and handling includes components and activities associated with the production facility, feedlot, manure and wastewater storage and treatment structures and areas, and any areas or mechanisms used to facilitate transfer of manure and wastewater. For most concentrated animal feeding operations (CAFOs), addressing this element requires a combination of conservation practices, management activities, and facility upgrades designed to meet the pro - duction needs of the livestock operation, while addressing environmental concerns specic to each operation. Important point: Manure storage provides for better use of farm labor; better use of equip- ment; increased ability to apply manure nutrients when they are most needed by the crop; increased ability to apply manure at times that avoid adverse climatic and soil conditions, such as during saturated or frozen soil; and minimizes the frequency of manure storage agitation and application events and the corresponding frequency of released odors. Various issues are associated with manure storage duration. For example, long-term storage (6 to 12 months) offers the operator the greatest exibility by accommodating long winter seasons and ts most cropping schedules. It also provides maximum exibility for scheduling custom spread - ing operations and, for operators who irrigate, it provides storage until the growing season. Mid- term storage (3 to 6 months) accommodates short periods with frozen, snow-covered, or saturated • • 7098.indb 99 4/25/07 5:30:18 PM © 2007 by Taylor & Francis Group, LLC 100 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) soil. However, this storage period may not work with traditional crop rotations. In addition, some pastures, grassland, or hay land might be needed for spreading during the growing season. Short- term storage (3 months or less) is best for warm climates with no long periods of frozen or saturated soil. Warm climate regions also provide more easily available pastures, grassland, and hay land for spreading. Frequent spreading requires, as needed, the availability of equipment and labor. The actual size of a manure storage system depends on the volume of manure produced per day. This depends on animal numbers or animal units (AU), species, and size. Manure volume is best determined by actually measuring the amount of manure that is hauled per year from a production facility, but it can be estimated from published values developed from experimental and eld studies if actual values are not available. Important point: In determining a storage volume for a farm, at least ve factors should be considered: (1) regulatory requirements, (2) animal type, size, and number, (3) storage time needed, (4) wastewater use and water wastage expected, and (5) rainwater runoff from manure-spread lots and evaporation. Siting is another factor to be considered when constructing manure storage and handling sys- tems, because most states have specic regulatory requirements that affect the siting and construc - tion of manure storage facilities. The extent of the various restrictions is usually a function of operation size. Consider the construction of earthen manure storage, for example. Site selection and construction of this type of manure storage requires soil and site investigation and evaluation proce - dures beyond what might be needed for a facility constructed of concrete or steel. These procedures ensure that soil leaching rates of nutrients and manure liquids will be acceptable. Additionally, an environmental assessment should be made to help minimize risks. The environmental assessment takes into consideration various levels of risk, including proximity to surface water and drinking water wells. It also answers questions such as: Is the construction area a oodplain? Are homes, public use areas, or businesses nearby at high or low risk? Are neighbors downwind of prevailing weather winds? Is the site elevation lower or higher than the storage elevation? Is the storage facility site highly visible because of location close to a road, or are the topography, vegetation, or buildings congured to visually screen the storage facility? Is water runoff situated in a manner that diverts it around, instead of owing into, the manure storage? Manure storages often must take into consideration separation distance requirements. Specic requirements vary by site and can be determined by checking with local and state authorities. Setback distances are intended to reduce the environmental impact of a manure storage facility on off-farm dwellings, businesses, and public entities, such as roads, parks, and churches. These distances usually depend on the size of the livestock and poultry operation, type of manure stored, and whether the storage is covered. Setback distance is measured from the manure storage structure to the nearest nonowned residence, public building, or entity. The regulatory agency may require that public notice be given to neighbors within a certain distance (for example, within 1.5 times the required setback) before construction begins or before the operation permit can be obtained. Important point: The regulatory setback distance, with respect to locating a site for animal manure storage, is based on horizontal distance from manure storage to some feature, such as neighboring residences or water supplies. Important point: Separation distances may also be required from groundwater sources. A vertical separation (usually 3 to 5 ft) may be required between the bottom of an earthen storage facility and the seasonal high water table. Locating a manure storage structure in a oodplain presents several potential hazards. The facility may be inundated and structurally compromised because of ooding. In most locations, regulations • • • 7098.indb 100 4/25/07 5:30:19 PM © 2007 by Taylor & Francis Group, LLC Manure Storage 101 prevent or limit construction in oodplains, because oodwater can exert unbalanced, inward hydrau- lic pressure on earthen impoundments if the manure level inside the basin is lower than the water level outside the basin. Such pressure can impair the seal and compromise structural integrity. Before constructing an earthen storage or lagoon, a detailed soil and site evaluation is needed. When a site is found to have unsuitable soil materials for construction, a clay liner, synthetic liner, or soil amendment that modies the existing soil properties may provide a means to attain the required permeability. Key term: 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 that does not allow liquids to pass through easily. Clay loams and loams are relatively impermeable. Manure storages should be located over impermeable soil so that seepage will not pass down through the soil into the groundwater. In this chapter, we describe various types of manure/wastewater storage and handling systems. In addition, using data derived from the National Resources Conservation Service (NRCS/USDA) document Manure and Wastewater Handling and Storage Costs (2005), we focus on the costs involved in operational needs of the various manure storage/handling systems. 4.2 TYPES OF MANURE STORAGE AND HANDLING SYSTEMS Livestock and poultry manure is handled either as liquid, slurry, or solid in U.S. production facili- ties. Storage structures for these handling mediums include earthen slurry basins or pits, lagoons, runoff holding pounds, unroofed slurry pits or tanks (not roofed), below-building pits (concrete), slurry pits, reception pits, roofed tanks (earthen or concrete), uncovered storage (steel or concrete) and covered storage (earthen or concrete pad) for solid manure. Important point: Handling liquid and slurry manure is considered to be easier to automate than handling solid manure. 4.2.1 runoff holDing PonDS Runoff holding ponds are typically located in areas where they can use natural surface-drainage conditions. These storage systems temporarily store runoff water from a feedlot until it can be applied to the land. Lot runoff must pass through a settling facility before going to the holding pond. The holding pond is not intended to receive roof water, cropland drainage, or other unpolluted waters. Holding ponds do not treat manure as lagoons do; the only store it until it can be spread. Runoff holding ponds are typically of earthen or concrete construction. They must be sealed to prevent seepage into groundwater. Holding-pond bottoms tend to seal naturally. The storage volume should be adequate to hold the runoff expected from the lot for the length of storage. The required storage capacity depends on desired length of storage, source of liquids and runoff water, rainfall duration and frequency, and the balance between rainfall and evaporation. The runoff holding pond is usually emptied by pumping and land application using some type of irrigation. The holding pond should be emptied before it is full, when wastewater can inltrate the soil. Soil should not be frozen, frosted, overly wet, or snow covered. The holding pond should be emptied completely to assure maximum capacity for runoff. Advantages of runoff holding ponds include their applicability for storm events in arid regions, storage of feedlot storm runoff, and their ability to be managed with irrigation equipment. Dis - advantages include the need to separate solids from liquids using a settling basin, soil evaluation requirements, the need for proper soil material, and seal construction. In addition, runoff holding ponds are not appropriate for regions with shallow water tables or high-risk geology. • 7098.indb 101 4/25/07 5:30:19 PM © 2007 by Taylor & Francis Group, LLC 102 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) 4.2.2 lagoonS Lagoons are earthen structures that provide biological treatment, as well as storage, of manure liq- uid. Liquid waste is biodegraded to convert organic matter (wasted feed, feces, and urine) in animal manure to a more stable end product. As with earthen storages, a seal on the bottom and sides is needed in some soils to meet permeability requirements. Advantages of lagoon storage include frequent crop irrigation in western states, feasibility for long-term storage, ability to be sized for lot runoff and fresh water inputs, biological treatment of manure, ability to be managed with irrigation equipment, and a relatively low storage cost per ani - mal unit. Disadvantages include the large land area needed for construction; the high phosphorus levels in sludge if not regularly agitated and removed; the requirement for soil evaluation, proper soil material, and seal construction; the need for an appropriate site or soil type; lack of aesthetics, public concerns over odor; and relatively high emissions of nitrogen and greenhouse gases. Important point: Lagoons in colder climates must be larger than lagoons in warmer cli- mates because bacterial action is greater and more efcient at warmer temperatures. 4.2.3 earThen Slurry baSinS or PiTS Depending on soil and site conditions, earthen slurry basins and pits are low-cost storage options. However, they are designed to store manure only and are not treatment systems. The design is simi - lar to but smaller than lagoons. A seal on the bottom and sides may be needed to meet permeability standards required by regulation. A larger land area is needed for construction of earthen structures because of the need for berms, and front and back berm slopes must be gentle enough to be properly maintained and to prevent erosion. Maintenance requirements are also greater than those for fab - ricated structures because of the need to maintain a well-trimmed vegetative cover on and around the berm to allow easy visual inspection and prevent tree roots from penetrating the berm. Planned access points for agitation and pumping should be part of the design to minimize soil erosion and damage to the storage line. Advantages of storing manure in earthen slurry basins or pits include: the relatively high nutri - ent density compared to lagoons, low to moderate nutrient loss, manure may be injected or incor - porated, they are less expensive than concrete or steel tanks, and they can be sized for lot runoff and minimal fresh water inputs. Disadvantages include: higher odor potential because of greater surface area; rainfall adds extra water; they may be difcult to agitate properly; they require soils evaluation, proper soil material, and seal construction; they require relatively expensive application equipment; the large number of loads that must be removed when the storage is emptied; and they are not appropriate for regions with a shallow water table or high-risk geology. 4.2.4 Slurry PiTS or TanKS Unroofed slurry pits and tanks are fabricated tanks constructed with concrete or coated metal (glass-lined steel). Manure is typically drained, scraped, or ushed from the production building to the storage structures. These storage structures are typically pre-engineered packaged units that are less subject to specic design and construction procedures by the livestock producer. Important point: Dangerous manure gases are likely to be released during agitation of slurry-stored manure. The advantages of slurry pits and tanks include: a relatively high nutrient density. Low to mod - erate nutrient loss and manure may be injected or incorporated. Disadvantages include: higher costs than earthen structures, more odor than covered storage, rainfall adds extra water, may not • • 7098.indb 102 4/25/07 5:30:20 PM © 2007 by Taylor & Francis Group, LLC Manure Storage 103 be compatible with systems having signicant lot runoff or high water use, and require relatively expensive application equipment. Important point: Slurry manure systems require less storage volume than lagoons. 4.2.5 below builDing PiTS The below building pit, often called a “deep pit,” is a common type of slurry storage. Here, manure is deposited directly through slotted oors into the pit below. Advantages of below building pits include relatively high nutrient density, low to moderate nutri - ent loss, manure may be injected or incorporated, and no rainfall effects. Disadvantages include: more expensive than earthen storage, odor, animal and worker health problems may result with prolonged exposure to manure gases, may require pit ventilation, not appropriate for regions with a shallow water table, high-risk soil conditions or geology, relatively expensive application equip - ment, and manure solids are more difcult to remove. 4.2.6 Slurry PiTS, reCePTion PiTS, or roofeD TanKS With slurry pits, reception pits, and roofed tank structures, manure is usually scraped from the pro- duction buildings and may ow into the tanks by gravity or be pumped into the tanks from a collec - tion sump or reception pit. These manure storage structures are either earthen or concrete. Adequate agitation is necessary to suspend solids and facilitate complete removal of the contents of these manure tanks. Fabricated tanks are usually the least costly to cover if odor becomes an issue. Advantages of slurry pits, reception pits, and roofed tanks include: relatively high nutrient den - sity, low to moderate nutrient loss, manure may be injected or incorporated, and they are not subject to rainfall effects. Disadvantages include: they are more expensive than earthen storage, may have more odor, may require pit ventilation, may not be compatible with systems that allow signicant lot runoff or high water use, and they require relatively expensive application equipment. 4.2.7 SoliD Manure Typical uncovered solid manure storage structures store litter from poultry (turkeys, layers, broilers, and ducks), separated or scraped solids from swine and dairy operations, manure collected from outside beef feedlots, and other solid oor/manure pack shelters involving large amounts of bed - ding. Uncovered solid manure structures are typically used in low-rainfall (arid) areas where they are well-drained; the material is stacked or stockpiled for subsequent spreading. Regulations may required contaminated runoff from these structures be collected and disposed of in an environmen - tally sound manner. Advantages of uncovered solid manure storage structures include: less expensive than roofed storage, high nutrient density, owners do not have to haul water, low nutrient loss (but higher than a covered storage), and are most applicable in arid regions. Disadvantages include: rainfall/runoff contamination potential, runoff controls may be required, not applicable as sole storage for sys - tems with lot runoff or high water use, bedding may be required, and are less applicable in humid regions. 4.2.8 roofeD or CovereD SoliD Manure In higher rainfall regions, roofed or covered solid manure storage structures usually have concrete bottoms and may have concrete walls to conne the solids and provide push walls for stacking and loading of solids. These storage structures are an option where adequate amounts of bedding are used to make the manure a stackable solid. However, bedding contributes to the volume of manure that must be stored. • 7098.indb 103 4/25/07 5:30:20 PM © 2007 by Taylor & Francis Group, LLC 104 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) Advantages of solid manure (roofed or covered) storage structures include high nutrient density, lack of need for workers to haul water, little or no seepage, low nutrient loss, and no runoff from stacked manure. Disadvantages include higher costs than open stacks, inapplicability as sole storage for systems with lot runoff or high water use, and possible requirements of bedding. Important point: Water used in cleaning increases the volume of manure storage facilities need. Important point: Solid manure systems with bedding usually produce fewer odors than manure slurries since bacterial action produces fewer odorous compounds as the result of moisture content. 4.3 MANURE HANDLING AND STORAGE COSTS [Note: In this section, a group of “virtual” farms were established to provide a generalized approach, including various assumptions, to estimating needs and costs for manure storage and handling sys - tems by identifying major cost items involved. This approach was guided by the NRCS Agricultural Waste Management Field Handbook (AWMFH) (NRCS, 1992). In particular, much of the data con- tained within our virtual assessment is based on the NRCS’s Costs Associated with Development and Implementation of Comprehensive Nutrient Management Plan (CNMP; NRCS, 2005)]. This assessment does not address federal, state, and local regulatory requirements associated with animal feeding operations. Many states have, or are in the process of adopting, regulations that would require some livestock operations to implement systems that are equivalent to a CNMP or part of a CNMP. Some of these regulations impose stricter requirements than represented by the NRCS CNMP guidelines. Consideration of regulatory trends was given, however, to the determina - tion of CNMP needs particularly for large operations. Important point: This assessment did not attempt to account for the implementation of CNMPs or elements of CNMPs since 1997. Consequently, part of the costs presented in this assessment may have already been borne by some livestock operations. Important point: Cost estimates may be overstated somewhat because they do not account for innovation and technological advances that are expected to occur as the CNMP initia - tive is implemented. No attempt was made to account for payment by recipients for manure exported off the farm or charges to the livestock operation by recipients for accepting the manure. A variety of pay - ment arrangements presently exist, depending on traditions and markets established in the produc - tion region, the type of manure, and existing state and local regulations. In some cases, livestock operators are responsible for applying the manure to recipients’ land. For the purposes of this cost assessment, it is assumed that all manure exported off a farm would be given and accepted without payment, the livestock operation bears the cost of transporting the manure to the manure-receiving farm, and the off-farm land application cost is borne by the recipient. Important point: CNMP development and implementation costs are not estimates of the costs to producers of complying with USEPA regulations. No account was made of the nancial benets that might be realized because of operational needs implementation, including any savings in commercial fertilizer costs for the additional acre - age that receives manure applications. The nutrient value of manure is considered one of the many benets of implementing operations needs. • • • • • 7098.indb 104 4/25/07 5:30:20 PM © 2007 by Taylor & Francis Group, LLC Manure Storage 105 No attempt was made to adjust costs for ination, even though some cost increases will certainly occur over the 10-year implementation period. To make this adjustment, one would need to know the rate at which operational needs would be implemented, which depends on regulatory incentives, nancial incentives, and the availability of technical assistance. Cost estimates reported here may therefore be understated to some extent, depending on the rate of ination and implementation over the next 10 years. This cost assessment also does not account for cost savings that could be realized by improvements in feed management. The virtual model used here shows that alternatives to land application of manure are needed in some regions of the country. Under the assumptions of the model simulation, 248 counties do not have adequate land to assimilate the manure produced in those counties when applied at rates that meet operational needs criteria. Most of these counties are co-located, reducing the opportunity to transport the manure to surrounding counties for land application. The amount of county-level excess manure represents about 16% of the total recoverable manure nutrients produced by all operations needs farms in the country. Included in the cost assessment are esti - mates of the cost of transporting this county-level excess manure off the farm. In our virtual CNMP model, we dene the basic set of production technologies in terms of representative farms for each livestock type. Representative farms dene broad groups of live- stock production facilities that, within a livestock sector, have similar characteristics for managing livestock and managing manure—in other words, a hypothetical farm with a typical animal waste handling system for a given livestock type. This set of representative farms was expanded to a larger set of model farms by adding the dimensions of size and location. Size categories for the dominant livestock type were selected to reect differences in production technologies by farm size. Geo - graphic regions generally reected major production regions, with further delineation by climate in areas where climate would be expected to inuence the kind of production system found. Not all representative farms are present in each size class and location. Each model farm is thus a represen - tative farm of a certain size in a specied location. Representative farms were derived from two sources of information: farmer surveys and expert judgment. Results from farmer surveys were available for dairies, swine, and layers. These surveys were not conducted for the specic purpose of inventorying manure-handling practices on farms but did include questions about the production technologies in use and a few questions about manure management. A team of USDA experts evaluated the survey results and identied the dominant manure management technologies, basing them on manure handling characteris - tics as much as possible. Only the most dominant technologies were included; technologies that occurred relatively infrequently in survey results were discarded. Farmer survey results were not available for fattened cattle, veal, conned heifers, broilers, pullets, or turkeys. For these livestock types, representative farms were derived by the team of USDA experts based on their knowledge of industry practices. In addition to providing a structure for deriving operational needs for the manure and waste - water handling and storage element, this analytical framework was used to assign costs related to manure testing and record keeping. A slightly expanded version of the framework was used to estimate operational needs development costs. Model Farms for Dairy Five representative farms were derived for dairy based on a 1996 National Animal Health Monitor - ing System (NAHMS) survey of 2,542 dairies in 20 states (USDA/Animal and Plant Health Inspec - tion Service [APHIS] 1996). The survey included questions about the manure storage facilities on the farm and the frequency of manure spreading. Production technologies for dairies were therefore dened in terms of manure storage. The ve representative farms are: 7098.indb 105 4/25/07 5:30:21 PM © 2007 by Taylor & Francis Group, LLC 106 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) 1. Essentially no storage, frequent spreading 2. Solids storage (typically outside, separate from pens, but may include some manure pack and dry lot conditions); no appreciable liquid storage 3. Liquid to slurry storage in deep pit or aboveground tank; some solids storage; no earthen basins, ponds, or lagoons; typically less than monthly spreading 4. Primarily liquid manure stored in basin, pond, or lagoon; some solids storage for outside areas; typically less than monthly spreading 5. Liquid system (any combination of 3 and 4); primarily used in the West and Southeast; often associated with manure pack; and solids spreading in the West. Model Farms for Layers Three representative farms were derived for layers based on a 1999 NAHMS survey of 526 layer farms in 15 states (USDA/APHIS, 1999). The survey included a question about the type of facility used relative to manure collection and handling. Production technologies for layers were therefore dened in these terms. Five types of systems were identied in the survey, but they were combined into three groups of representative farms because of similar operational needs and cost assump - tions. The three representative farm types are: High rise (pit at ground level with elevated house) or shallow pit (house not elevated) Flush system to lagoon Manure belt or scraper system. Model Farms for Swine Five representative farms were derived for swine based on two farmer surveys: a 1995 NAHMS survey of 1,477 swine farms in 16 states (USDA/APHIS, 1995) and a 1998 Agricultural Resource Management Survey (ARMS) on 1,600 swine farms in 21 states (USDA/ERS, 2000). The surveys included questions about the type of facility used to rear swine and the type of manure handling and storage system. Production technologies for swine were therefore dened in these terms. The initial breakdown was made using the NAHMS survey results. The ARMS results were used to update the representation of connement facilities that had storage ponds or lagoons and were used to estimate representation in the West. The representative farms are: 1. Total connement with liquid system, including lagoon 2. Total connement with slurry system; no lagoon 3. Open building with outside access and liquid to slurry system (holding pit under slat or open ush gutter) 4. Open building with outside access and semisolid to solid wastes (mechanical scraper/trac - tor scrape/hand clean) 5. Pasture or lot with or without hut Model Farms for Other Confined Livestock Types Survey results for the remaining conned livestock types are not available. A team of USDA experts dened the predominant production technologies for each livestock type. Representative farms were dened as follows: Fattened cattle 1. Dry lot (small) scraped on a frequent basis, manure stacked until application 2. Dry lot with manure pack and occasional complete clean out and removal; at least rudi - mentary runoff collection/storage. • • • 7098.indb 106 4/25/07 5:30:21 PM © 2007 by Taylor & Francis Group, LLC Manure Storage 107 Confined heifers 1. Connement barns with bedded manure; solids handling 2. Small open lots with scraped solids and minimal runoff control Veal 1. Connement house with liquid and slurry components Turkeys 1. Connement house 2. Turkey ranching (building with open sides and lot) Broilers 1. Standard broiler house; complete litter clean out or cake out Pullets 1. High-rise or shallow-pit connement house Model Farms for Pastured Livestock Types 1. Pasture with heavy use area 2. Pasture with windbreak or shelterbelt 3. Pasture with lot and scrape-and-stack manure handling 4. Pasture with barn for shelter Major cost items for manure storage and handling are broken down into the following components: Mortality management (poultry and swine) Lot upgrades Clean water diversions (including roof runoff management, earthen berms, and grassed waterways) Liquid treatment (small dairies) Collection and transfer (including solids, liquid, contaminated runoff, and pumping) Settling basins Solids storage Liquid storage Slurry storage Runoff storage ponds Cost estimates for conservation practices for pastured livestock are included in the manure han - dling and storage element. Components for farms with pastured livestock types include: Fencing Water well Watering facility Heavy use area protection Windbreak or shelter break establishment Solids storage Filter strip • • • • • • • • • • • • • • • • • 7098.indb 107 4/25/07 5:30:21 PM © 2007 by Taylor & Francis Group, LLC 108 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) Manure handling and storage costs for the system are associated with the dominant livestock type on each farm. However, many of these farms have other conned livestock types on the farm. The costs associated with addressing needs for the secondary livestock types on the farm, for the most part, are incorporated into the system costs for the dominant livestock type. Any additional costs are assumed minor and are not estimated. For several compounds, however, costs are based on the amount of recoverable manure produced on the farm (handling and transport weight), which includes recoverable manure from all livestock types on the farm. 4.3.1 MorTaliTy ManageMenT For our “virtual” farms, the cost of mortality management is included for all poultry and swine farms. For dairy and fattened cattle, existing mortality management practices are assumed to be adequate in most cases. Various acceptable methods were used to manage poultry and swine mor - tality, such as composting, incineration, burial pits, and freezing. Composting was selected as the representative technology for assessing system operational costs. Important point: For illustrative and descriptive reasons and to broaden applicability, throughout this section, for our virtual farms we substitute the general term “operational costs” or “operational needs” for CNMP. 4.3.1.1 Poultry The cost of mortality management for poultry was determined on a per-house basis. A concrete slab covered with a timber structure comprised the composting facility. Capital and operating costs of the structure were based on costs reported by the North Carolina Cooperative Extension (1999) for a 100,000-broiler ock. The cost of the timber structure and concrete oor was $3,600, and the cost of water service for the facility was $150, resulting in an annual capital cost of $559. Operating costs included labor (27.5 hours per ock at $10 per hour per year) and machinery rental ($20 per hour at 51 hours per year), for a total of $2,533 per year. For the 25,000-bird broiler house used as the standard house size in this study, annual costs were $140 for capital and $633 for operating costs. Costs for the other poultry livestock types were estimated by prorating the cost for broilers based on capacity needed for the other poultry types. The capacity needed was estimated using a method published by the North Carolina Cooperative Extension (1996). Maximum capacity was estimated by multiplying the expected daily death rate by the market weight (maximum weight), and then multiplying by the number of birds per house. Although mortality takes place throughout the production cycle with birds at various weights, for most operations the majority of the mass that must be dealt with occurs near the end of production, when birds are closest to their market weight. To ensure adequate composter space, capacity is based on the greatest demand to handle bird mor - tality. Calculations are shown in Table 4.1. • TABLE 4.1 Capacity Need Calculations Poultry type Birds per house Market weight (lb/bird) Mortality rate (%) Mortality rate (lb/d) Annual capital cost per house ($) Annual operating cost per house ($) Broilers 25,000 4.5 0.1 113 140 633 Layers and pullets 50,000 4.0 0.033 66 82 371 Turkeys for slaughter 5,000 19.2 0.080 77 96 433 Turkeys for breeding 8,000 18.8 0.100 150 187 846 7098.indb 108 4/25/07 5:30:21 PM © 2007 by Taylor & Francis Group, LLC [...]... 248 AU 41 5 AU 2,075 AU 41 5 AU 2,075 AU 4, 342 ,47 7 2,893 ,41 4 1,321,828 1,580,733 4, 573,781 1,607,863 3,130,253 5,216,732 7,0 54, 470 26,515 ,40 3 25,387,588 1,165,377 3,222, 244 5,3 84, 140 26 ,40 8,062 6,577,275 32, 348 ,49 9 65,137 52,081 23,793 28 ,45 3 68,607 28, 942 46 ,9 54 78,251 105,817 397,731 380,8 14 17 ,48 1 48 ,3 34 80,762 396,121 98,659 48 5,227 9,707 7,762 3, 546 4, 240 10,2 24 4,313 6,997 11,662 15,770 59,2 74. .. Plains Pacific 22,899 71, 540 12,352 52,817 7,9 64 31,598 26,309 7,9 74 2,155 1,312 1 ,46 8 1,363 4, 1 84 1,595 2,012 5,6 84 545 2 14 436 250 980 303 345 1 ,47 9 65 39 44 41 126 48 60 171 Southeast Southern Plains All types 12,807 10, 941 297,201 2,0 74 3,508 1,807 549 775 389 62 105 56 Total costs ($) 2,987 1, 647 2,181 1,669 6,177 1,976 3,088 7,731 2,901 4, 776 2,509 Source: NRCS/USDA (20 04) Chapter Review Questions... 24, 4 04 24, 072 16,1 04 5,308 13,922 25,170 8,695 8,802 6,787 8,695 8,802 6,787 11,786 5,168 8,7 94 17 ,41 4 28,961 30,129 49 ,825 6,983 20 ,45 9 24, 316 21,008 41 ,133 24, 736 3,637 3,587 2 ,40 0 791 2,075 3,751 1,296 1,312 1,011 1,296 1,312 1,011 1,756 770 1,311 2,595 4, 316 4, 490 7 ,42 5 1, 041 3, 049 3,6 24 3,131 6,130 3,686 18.18 per head 17. 94 per head 12.00 per head 9.53 per AU 4. 61 per AU 8. 34 per... per head is $4. 47 • If the number of head is more than 300, the cost per head is $3.58 Number of animals Linear feet of pipe Pipe cost per foot ($) Number of 30-foot berms Berm cost ($) Total cost installed ($) Cost per animal ($) Annual cost per animal ($) 75 150 600 200 360 1,200 12 12 12 1 1 3 115 115 345 2,515 4, 435 14, 745 34 30 25 5.07 4. 47 3.58 Most of these operations already have this practice... Taylor & Francis Group, LLC 7098.indb 1 14 4/25/07 5:30: 24 PM 115 Manure Storage Table 4. 2 Cost Estimates for Liquid Collection with Flush Systems for Dairy Farms Operation Cost component 100-head ($) 200-head ($) 300-head ($) 7,801 5,721 562 5,367 19 ,45 1 2,899 1,185 28.99 15,602 11 ,44 2 562 5,367 32,973 4, 9 14 2,369 24. 57 23 ,40 3 17,163 562 5,367 46 ,49 5 6,929 3,5 54 Flush tank Collection tanks Collection... with scrape-and-stack manure handling system in the Midwest and Northeast Size 1 Animal number (head) Area of lot (ft2) Length of berm (ft) Cost of berm ($) Cost of berm per head ($) Linear feet of pipe CMP cost per foot ($) Cost of pipe installed per head ($) Annual cost per head ($) Size 2 Size 3 116 53,130 230 46 0 3.96 46 12 4. 76 308 141 ,080 376 752 2 .44 75 12 2.93 616 283,360 532 1,0 64 1.72 106... installation cost ($) 200 head 300 head 100 head 83 248 41 5 2,075 41 5 2,075 45 0 41 5 1,122,000 1,683,000 561,000 287,363 708,225 1,101,176 5, 245 ,933 1,068,808 5,037, 143 2, 148 ,585 1,101,176 20,196 30,2 94 12, 342 6,322 15,581 19,821 78,689 19,239 75,557 32,229 19,821 Annual installation cost ($) 3,010 4, 515 1,839 942 2,322 2,9 54 11,727 2,867 11,260 4, 803 2,9 54 Cost per unit ($) 15.05 per head 15.05 per head... Only 15% of these operations were assumed to need to install this practice because of its common use © 2007 by Taylor & Francis Group, LLC 7098.indb 111 4/ 25/07 5:30:22 PM 112 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) All grassed waterways were assumed to be 30 ft wide The length varies by the size of the operation Per-unit costs were taken from the NRCS Field Office... class Number of farms AU for dominant livestock type AU for other livestock type Capital costs ($)** Operating costs ($)** Fattened cattle Milk cows 10,159 79,318 858 149 44 0 46 7,629 2,620 1,2 54 551 Swine Maintenance costs ($)** Total costs ($) Cost per AU of dominant livestock type ($) 229 79 9,112 3, 249 11 22 32,955 236 40 3 ,45 1 585 1 04 4,139 18 Turkeys 3,213 638 49 5,305 2 ,47 6 159 7, 940 12 Broilers... Layers/pullets 5,326 258 39 3,519 390 106 4, 015 16 Confined heifers/veal 4, 011 237 64 2,710 40 1 81 3,192 13 Small farms with confined livestock types 42 ,565 18 7 149 46 4 199 11 Pastured livestock types 61,272 107 10 NA NA NA 823 8 Specialty livestock types 2,131 NA 17 563 263 17 843 NA Large farms 19, 746 1,129 290 11,627 2,721 340 15,167 13 Medium farms 39 ,43 7 191 61 2 ,47 7 543 74 3,397 18 Small farms 198,018 . • 7098.indb 103 4/ 25/07 5:30:20 PM © 2007 by Taylor & Francis Group, LLC 1 04 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) Advantages of solid manure (roofed or covered). 115 2,515 34 5.07 150 360 12 1 115 4, 435 30 4. 47 600 1,200 12 3 345 14, 745 25 3.58 Most of these operations already have this practice in place or do not need it because of the ter- rain characteristics. 28.99 24. 57 23.10 Source: NRCS/USDA (20 04) . 7098.indb 115 4/ 25/07 5:30: 24 PM © 2007 by Taylor & Francis Group, LLC 116 Environmental Management of Concentrated Animal Feeding Operations (CAFOs) turkey
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