Cooperative Approach to Land Application of Animal Waste in Tennessee

Transcription

1 Published in the proceedings of the Animal Production Systems and the Environment: An International Conference on Odor, Water Quality, Nutrient Management and Socioeconomic Issues, Des Moines, Iowa Vol. 1: pg Permission has been obtained to allow reprinting of this article. Cooperative Approach to Land Application of Animal Waste in Tennessee R. T. Burns 1, T. L. Cross 2, K. J. Stalder 3, R. F. Theurer 4 ABSTRACT Many dairy and swine producers in Tennessee and the United States utilize liquid manure storage systems coupled with land application of liquid manure slurry. The proper management and application of liquid manure is critical to avoid adverse environmental impacts. Many producers do not own the equipment necessary to efficiently spread animal waste slurry stored in liquid manure systems over the necessary acreage. Tennessee farmers have been active in providing their own solution to this challenge by forming non-profit animal waste management associations. Producers can hire these associations, on a contract basis, to land apply liquid manure for a reasonable fee. Many farmers can not afford to purchase this equipment for their farm alone. By acting together, farmers have reduced capital investment required to manage their waste and follow environmentally sound land application practices. This paper provides a case study of one of these cooperative associations, the Coffee-Franklin-Warren Animal Waste Management Association (CFW) located in southern-middle Tennessee. Although the CFW is only one of seven associations established in the state, sound management and good record keeping have helped it become the model which other Tennessee associations follow. Analysis of 3 years of CFW records provides insight into the effectiveness of this association. Summaries of the systems pumped, and the nutrients applied provide an overview of typical liquid waste storage systems currently utilized by swine and dairy producers in the state. Keywords: Animal waste, Land application, Nutrient management, Cooperative associations INTRODUCTION Non-profit, farmer organized and operated animal waste utilization associations have proven themselves effective in Tennessee. As shown in Fig. 1, seven such organizations are currently operational across the state of Tennessee. The Coffee-Franklin-Warren (CFW) Animal Waste Utilization Association, named for the three Tennessee counties it primarily serves, has become the successful model other associations have patterned. The initial funding to acquire the pumping equipment for six of the seven associations was provided by grants from the Tennessee Department of Agriculture. The Chickasaw-Shiloh Association operates with equipment funded by a demonstration grant from the Tennessee Valley Authority. The equipment utilized by each association, while not identical, is very similar. The associations have utilized University of 1 Assistant Professor Agricultural and Biosystems Engineering Department, University of Tennessee. 2 Associate Professor Agricultural Economics and Resource Development Department, University of Tennessee. 3 Assistant Professor Animal Science - Swine Section, Swine Extension Specialist, University of Tennessee 4 Coffee-Franklin-Warren Animal Waste Utilization Association Technician

2 Tennessee Agricultural Extension Service, Natural Resource Conservation Service, and Tennessee Department of Agriculture personnel for technical assistance and advice with equipment selection. The final decisions as to the type, brand, size, etc. of equipment purchased are made by the association members. Although all of the associations operate in a similar manner, each associations by-laws and operating procedures vary. The specific information given in this paper will be reflective of the CFW Association. Figure 1 Map of Association Locations in Tennessee The CFW Association has proven to be one of the most successful animal waste utilization associations in the state as demonstrated by its producer utilization and financial solvency. Observation of all seven associations over the past five years has indicated that technician reliability (or the lack thereof) will make or break a cooperative animal waste utilization association. Several of the associations have experienced periods without a technician, and some even originally chose to operate without a technician. In periods without a technician associations suffered similar problems: equipment breakdowns were frequent, and scheduling the transportation and usage of equipment was troublesome and unreliable. In instances where an association seemed to function without a technician, someone (typically a farmer, District Conservationist or Extension Agent) had assumed the role of technician in an unpaid capacity in addition to his/her existing job requirements. Associations functioning in this mode seldom did so for an extended length of time. The CFW Association has maintained the same technician throughout all three years of operation. A reliable operator who provides excellent preventative maintenance has enabled this association to remain viable long after the original grant money was exhausted. EQUIPMENT SETUP All of the Tennessee associations use big-gun systems to land apply animal waste from liquid systems such as lagoons, holding ponds and tanks. In addition, some associations have purchased tank spreaders and poultry litter spreaders as well. Each association selects the equipment which best fits the needs of its clients. A soft-hose reel system using a big-gun

3 (Nelson SR200) is the standard system used by the associations for liquid manure land application. A 133 KW (152 HP) power unit (Cummins B 5.9 diesel engine) powers an open impeller slurry pump (Cornell 4NHDH) capable of handling dairy or swine waste. System flow averages around 3000 liters per minute (800 gallons per minute) depending on the elevation encountered at each farm. The gun retrieval speed is varied by location in order to achieve the desired cm / hectare (inches / acre) application rate for each situation. Pumping agitators are used to agitate the stored manure before and during pumping. In deep lagoons or holding ponds the agitator is used to prevent pump cavitation by connecting the output fill pipe from the agitator to the pump intake in order to provide a pressure feed to the pump. Band-lock aluminum pipe is used to transport the manure from the storage pond or lagoon to the land application site. Each association has approximately 914 meters (3000 feet) of aluminum pipe. The pipe is fifteen cm (six inch) band-lock ASTM Class 150 aluminum. The soft hose reel contains 200 meters (660 feet) of 11.5 cm (4.5 inch) vinyl hose which is laid out in a J configuration, as shown in Fig. 2. By locating the aluminum supply pipe in the center of a pull, 400 meters (1320 feet) can be covered in one pass. Each tow path is set at approximately 70 percent of the total gun throw diameter to provide better application uniformity. Producers who hire the CFW Association are required to provide a tractor to power the agitator and a tractor to transport the aluminum pipe trailer and move and anchor the hose reel. A minimum 75 KW (100 HP) tractor is recommended to power the pumping agitator. The reel has a small 4-cycle gasoline engine which is used to retrieve the big-gun via a steel cable during operation. The PTO from the tractor used to anchor the reel provides the power required to roll the soft-hose back onto the horizontal reel after usage. The cost to purchase the original equipment for an association has averaged around $70,000. RECORD KEEPING AND NUTRIENT MANAGEMENT The CFW Association has maintained good record keeping since its inception in A computer data-base containing information concerning each waste pump-out is maintained in the local soil conservation district office. The following information is recorded for each pump-out: farm, county, move date, pump date, hours of pump time, feet of pipe used, system flow rate, total volume pumped, percent solids, total pounds of N, P and K applied, calculated dollar value of nutrients applied, cost to producer, calculated nutrient value return from each dollar of cost, type of operation pumped, facility type, time since last pumped, acreage utilized in land application, pounds per acre application rate of N, pounds per acre application rate of P as P 2 O 5, pounds per acre application rate of K as K 2 O, soil ph, P soil test results, K soil test results, N soil test recommendation, P 2 O 5 soil test recommendation, K 2 O soil test recommendation and crops to be planted following application. The associations have taken a proactive stance toward proper manure application and nutrient management. The CFW producer-association lease agreement requires analyses of waste samples from each facility pumped and soil samples from each field where waste is spread. These samples are taken and submitted by the association technician. The results are returned to the association where they are recorded in the data-base and then forwarded to the producer. Beginning in 1998 the CFW Association will apply a 25 percent discount on the hourly pump rate from June 1 st through October 15 th. This should encourage better manure management and spreading of manure when weather and soil conditions are dry.

4 ANALYSIS OF COFFEE-FRANKLIN-WARREN ASSOCIATION RECORDS The CFW Association began providing service in the spring of During the time period from March, 1995 through December, 1997 the association has pumped a total of 94 animal waste lagoons, holding ponds and storage tanks. The CFW association has been utilized equally by dairy and swine producers (53% of the facilities pumped were dairy operations and 47% swine operations). Tables 1 and 2 provide average values for dairy and swine waste respectively taken from the CFW Association records. Table 1. Average Pump-Out Data From 50 Dairy Operations, Average Minimum Maximum Hours pump time System flow l/min (gal /min) Total volume pumped liters (gallons) Pipe distance meters (feet) 2900 (766) 1136 (300) 3218 (850) 1,384,000 (365,681) 200,000 (52,800) 4,070,000 (1,075,500) 437 (1,433) 46 (150) 1052 (3,450) % solids Pump-out cost $ 1,312 $ 309 $ 3,025 Table 2. Average Pump-Out Data From 44 Swine Operations, Average Minimum Maximum Hours pump time System flow l/min (gal /min) Total volume pumped liters (gallons) Pipe distance meters (feet) 3028 (800) 1552 (410) 3218 (850) 1,528,000 (403,767) 326,000 (86,100) 5,809,000 (1,534,500) 402 (1,319) 64 (210) 914 (3000) % solids Pump-out cost $ 1,297 $ 462 $ 4,175

5 Through educational programs during CFW meetings, field advice provided by the association technician and required sampling, the CFW Association has helped educate producers of the need to balance available nutrients applied with estimated crop nutrient requirements. By calculating the estimated return in nutrient value for each facility pumped, the CFW Association has shown farmers the potential economic incentive from matching nutrient application and crop utilization. Tables 3 and 4 show the average nutrient content and nutrient dollar value of material land applied by the CFW Association for dairy and swine wastes respectively. Table 3. Average Dairy Waste Nutrient Content, Calculated Value 5 and B-C Ratio Nitrogen (TKN) 6 Phosphorus (as P 2 O 5 ) Potassium (as K 2 O) mg / l (lb / 1000 gal) 996 (8.3) 1548 (12.9) 1344 (11.2) $ Value $ 980 $ 1,246 $ 629 Benefit / cost ratio Nutrient value calculation represents average total per farm value and is based on $0.70 per kg N, $0.57 per kg P and $0.33 per kg K. To realize the total calculated value of each nutrient the crop nutrient requirement and nutrient application rate must be balanced. 6 - Value represents 50 % of measured TKN which is assumed present and available after application. In order for a producer to realize the benefit-cost ratios associated with a specific nutrient as shown in Tables 3 and 4, the crop nutrient requirement and nutrient application rate must be balanced. This is easily done for a single nutrient, but seldom balances for all three macro nutrients simultaneously. For instance when crop nitrogen needs and application rates are balanced, phosphorus and potassium may be over-applied, and the benefit-cost ratios shown for these two nutrients would not be realistic. Actual benefit-cost relationships should be calculated on a case-by-case basis by balancing the most limiting nutrient to the crop need, and allowing credit from the remaining two nutrients as applied. The pump-out cost charged to the producer results from the addition of charges from set up, agitation, pumping and take down. The set up charge includes a $200 equipment relocation fee and $15 per hour labor rate while the technician Table 4. Average Swine Waste Nutrient Content, Calculated Value 7 and B-C Ratio Nitrogen (TKN) 8 Phosphorus (as P 2 O 5 ) Potassium (as K 2 O) mg / l (lb / 1000 gal) 816 (6.8) 2640 (22) 744 (6.2) $ Value $ 897 $ 2,478 $ 360 Benefit / cost ratio Nutrient value calculation represents average total per farm value and is based on $0.70 per kg N, $0.57 per kg P and $0.33 per kg K. To realize the total calculated value of each nutrient the crop nutrient requirement and nutrient application rate must be balanced. 8 - Value represents 50 % of measured TKN which is assumed present and available after application.

6 assists with set up. A fee of $40 per ½ day is charged for the agitator. A rate of $110 is charged while the pump system is running (power unit, pump, piping and gun in operation). A $15 per hour rate is also charged for technician to assist with dismantling and loading of the system components. While it is required for producers to provide two men to assist with set up and dismantling of the equipment, such work is always supervised by the association technician. This arrangement ensures that all equipment is assembled and disassembled properly. Set up time averages 2 hours and take down time averages 1.5 hours. The producer contracting services signs a lease agreement with the association and is required to pay a $300 deposit to reserve their lease. All work is conducted on a first come-first serve basis. The technician reserves the right to make minor schedule rearrangements when it is in the overall interest of the association based on the geographical proximity of job sites. Additional costs are incurred by producers that hire the association for the tractors they must provide to agitate, move pipe and move the hose reel. These costs include fuel, repair and maintenance costs of operation, as well as ownership costs for depreciation, interest, insurance and housing. These added costs are not included in the average pump-out costs reported in Tables 1 and 2. The estimated benefit-cost ratios from the dairy and swine operations that were pumped by the CFW Association indicate that much of the direct cost paid by producers to the Association is recovered through the value of the nutrients applied. Other benefits provided by the associations include reduced farm investment requirements and improved understanding and use of environmentally sound waste application methods. CONCLUSIONS Interest in producer organized and operated cooperative animal waste management organizations continues to increase in Tennessee. Although associations are based in specific counties, most will provide service in adjoining counties when no jobs are waiting in their organizing counties. As more associations are chartered across the state, an increasing number of farmers will have this service available. The ability to efficiently land apply large volumes of waste has resulted in fewer liquid system discharges were services are available. When establishing new waste utilization cooperatives, the CFW Association provides an excellent model for Tennessee and other states to follow. REFERENCES CFW Association By-Laws of the CFW Animal Waste Utilization Association, Inc. CFW Association CFW Animal Waste Utilization Association, Inc. Lease for Waste Irrigation Equipment. Thuesen, H.G Engineering Economy 4 TH Edition. Prentice-Hall, Inc., Englewood Cliffs, New Jersey.