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Capturing Manure's Value

Article-Capturing Manure's Value

This nutrient management special report covers regulations and their cost, pollution and solutions, digesters and lengthening lagoon life.

Six steps to understanding the new CAFO rules

If you're befuddled by the new Environmental Protection Agency (EPA) regulations on concentrated animal feeding operations (CAFOs), you're not alone. But, hopefully, we can clarify the basic changes and help you figure out where to go for help.

Step One is understanding that EPA's CAFO regulations are the new minimum standards for all livestock operations that meet EPA's definition of a CAFO. That doesn't mean they're the ultimate regulations. States can always choose to pass more rigorous standards and to enforce them. In many states, this is the case for certain types of livestock operations and especially for producers of certain species of livestock. When state or local laws and regulations exceed the minimum requirements for federal standards, then those are the rules in force. When state standards are less restrictive, the EPA standards are the rules in force.

Step Two is to understand the permitting process. If state standards are the rules in force, then the state agencies charged with enforcement will be the permitting agencies. If EPA's standards for a particular operation are more rigorous than the state's rules and laws, then EPA is the permitting agency. However — and this is a big however — EPA in most cases delegates its permitting and enforcement authority to the states, which assign it to the agency they choose.

Therefore, livestock producers who operate CAFOs must find the correct agency to get the applicable rules and permits. That agency will be the primary information source for regulations.

In a few cases, CAFO operators may be required to get permits from two sources. Operators who don't know which is their permitting agency might do best to call the EPA office for their region. (See page NM4, “Who To Call”).

Step Three is to determine whether your operation qualifies as a CAFO by EPA's definition. CAFOs now fall into three categories: large, medium and small. The rules that determine into which category you fall depend primarily on the combination of livestock species and number of animals confined (see Table 1).

Medium CAFOs will be regulated if a stream runs through the confinement area or there is a man-made conveyance for wastes to surface water. Small CAFOs will be regulated for the same reasons as mediums, or if they're deemed a “significant contributor of pollutants.”

Table 1. CAFO Thresholds
Industry Thresholds
Animal Type Large CAFO Medium CAFO
Dairy Cows 700 200-699
Veal Calves 1,000 300-999
Beef Cattle 1,000 300-999
Swine 2,500 (55 lbs. or more) 10,000(<55 lbs.) 750-2,499 (>55 lbs.) 3,000-9,999 (<55 lbs.)

Although there are several significant changes to the old rules, three major changes are:

  1. “Dry” poultry manure handling systems are now included in the CAFO regulatory process.

  2. The exemption for facilities that could prove they controlled nutrient runoff in 25-year, 24-hour storm events is gone.

  3. Every CAFO that falls under the new guidelines will have to produce and live by a nutrient management plan for land application of wastes, particularly the amounts of nitrogen and phosphorus.

Step Four is to understand the role of the Natural Resources Conservation Service (NRCS) in the regulatory process. Simply put, NRCS is not a regulatory agency, but many of its recommended standards and practices are now essentially part of the law of the land. For example, land application requirements in NRCS's Code 590 will now be the minimum standard in every state, but many states will have standards more rigorous — in some cases for one species and, in other states, for many livestock species. This information can be obtained from local NRCS offices or viewed on its Web site:

NRCS and the land-grant universities are the technical resources for the implementation of the new EPA CAFO standards, since EPA regulations reference their codes and data as the minimum rules. Each state's NRCS should be able to deal with all technical issues facing a CAFO.

For example, nutrient management plans required of all CAFOs will use the NRCS Code 590 as a minimum standard. CAFO operators may depend on NRCS input in the development of these plans and even for engineering purposes if they don't provide their own engineering and nutrient management experts. Some large operations have these resources in-house and don't need the direct involvement of NRCS.

NRCS certifies all nutrient management planners, for itself and for all private entities. This is valuable knowledge for those seeking a certified nutrient planner.

Step Five is to understand the timetable for implementation of the new standards. There are too many nuances to capture in this single article, but your permitting agency can clarify these.

The schedules for compliance vary among existing facilities designated as CAFOs. Many of the regulations must be met by December 2006. New CAFO facilities must be compliant when they open.

Step Six is getting a handle on reporting requirements. This may be the most annoying for many operations, but it's a fact of life.

“I suspect one of the biggest hurdles for many producers will be the record-keeping requirements,” suggests Dan Waldner, Extension dairy specialist at Oklahoma State University.

There seems to be no one doing this on a custom basis, comparable to independent nutritionists, accountants or crop consultants. That means that, in the near future, CAFO operators must do it themselves.

Basic reporting requirements involve annual reporting of six items:

  • Amount of manure/wastewater generated.
  • Amount of manure/wastewater transferred.
  • Land application acres covered by nutrient management plan.
  • Land application acres used in the previous 12 months.
  • Summary of production area discharges.
  • Nutrient management plan development/approval statement.

The final rule requires permittees to indicate whether their plans were either written or reviewed by a certified Nutrient Management Plan planner, yet the agency is not requiring that the plan be developed or reviewed by one. EPA believes certified planners are valuable to these operations and having this information will help EPA and the states determine which plans need closer scrutiny.

Who To Call

If your operation falls under the new permitting guidelines but you don't know the permitting agency in your state, call your regional EPA office.

Region 1 — Maine, Vermont, New Hampshire, Massachusetts, Rhode Island, Connecticut.

Bruce Rosinoff, Boston, MA; (617) 918-1698.

Region 2 — New York, New Jersey. Andrea Coats; (212) 637-3850 or [email protected]

Region 3 — Pennsylvania, West Virginia, Virginia, Delaware, Maryland, Washington D.C.

Hank Zygmunt, Philadelphia, PA; (215) 814-5750 or [email protected]

Joseph Piotrowski, Philadelphia, PA; (215) 814-5715 or [email protected]

Region 4 — Kentucky, Tennessee, North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi.

Sam Sampath, Atlanta, GA; (404) 562-9229 or [email protected]

Region 5 — Ohio, Indiana, Illinois, Michigan, Minnesota, Wisconsin.

John Colletti (tribal contact), Chicago, IL; (312) 886-6106 or [email protected]

Arnie Leder, Chicago, IL; (312) 886-0133 or [email protected]

Steve Jann, Chicago, IL; (312) 886-2446 or [email protected]

Region 6 — Texas, Louisiana, Arkansas, Oklahoma, New Mexico.

Kenneth Huffman, Dallas, TX; (214) 665-8403 or [email protected]

Region 7 — Kansas, Missouri, Nebraska, Iowa.

Ralph Summers, Kansas City, KS; (913) 551-7418 or [email protected]

Region 8 — Utah, Colorado, Wyoming, South Dakota, North Dakota, Montana.

Debra Thomas, Denver, CO; (303) 312-6373 or [email protected]

Region 9 — California, Arizona, Nevada, Hawaii.

John Ungvarsky, San Francisco, CA; (415) 972-3963 or [email protected]

Region 10 — Washington, Oregon, Idaho, Alaska.

David Domingo, Seattle, WA; (206) 553-0531 or [email protected]

Annual cost will top $300 million

EPA says 15,500 facilities will be designated concentrated animal feeding operations (CAFOs) across the U.S., and will be regulated under the new rules. This will include 11,000 large facilities, 4,500 medium facilities and a limited number of small facilities. This will affect 60% of all manure produced by animal feeding operations.

The agency pegs the annual social costs of the regulations at $335 million, with the total drawn from compliance costs by CAFOs and administrative costs to federal and state governments.

Large CAFOs will spend $283 million (measured in pre-tax 2001 dollars). Medium CAFOs will spend $39 million per year, and small operations designated as CAFOs will spend $4 million per year. State and federal governments will spend $9 million per year.

The public will actually carry more of the cost than these numbers indicate because NRCS's Environmental Quality Incentives Program (EQIP) could provide several million dollars to CAFOs to help them accomplish technology objectives.

Further, EPA estimates that perhaps 285 existing CAFOs will be forced out of operation by the costs of compliance. This would be 3% of all large CAFOs.

EPA estimates that the total value of reduced pollution will be $204.1 million to $355 million per year. The estimate includes reductions in nitrate contamination of private wells; reduced eutrophication and pathogen contamination of coastal waters and estuaries; reduced public water treatment costs, etc.

EPA says the new rules will stop 56 million pounds of phosphorus now being released from CAFOs into the environment, in addition to 110 million pounds of nitrogen, 2.1 billion pounds of sediment and 911,000 pounds of metals.

The problem with P

For animal feeders, phosphorus is that sticky mess that won't go away

Lee Borck is establishing his own guidelines for phosphorus application on land that Ward Feed Yard farms around Larned, KS. The effort puts the operation well ahead of the curve for EPA's new CAFO regulations.

“We want to establish our own baseline rather than have the government tell us we can only put on 15 tons of manure,” says Borck, Ward Feed Yard president. Instead of a statewide NRCS-established level, Borck has found that, on irrigated alfalfa growing in sandy ground near the Arkansas River, he can apply 25 tons per acre of raw feedlot manure every other year with no buildup in phosphorus (P).

Ward Feed Yard has been monitoring manure samples for more than 10 years. The study on phosphorus use in alfalfa, conducted by Diamond Ag Research, is in the fourth year of its five-year run.

Borck's preemptive research is well warranted in the face of increasing regulation of all nutrients, but of P in particular. Even though environmental regulations in Kansas have been fairly rigorous in the past — such that only 300 animals qualify as a concentrated feeding operation — P applications by beef feedlots have never been regulated.

Because of EPA's CAFO regulations reference to NRCS Code 590, all the major nutrients certainly will be in the future.

As the minimum standard, NRCS's Code 590 says nutrient applications shall not exceed crop needs. This will be a change for animal feeders in many parts of the country. The patchwork quilt of regulations may continue, but the minimum standards say P and other nutrients must be accounted for.

Animal manure was historically applied according to nitrogen (N) needs, but that will all change. Manure, especially manure from hog and chicken operations, is very high in P and potassium in relation to plant needs for N.

The background

Depending on livestock species, about 70-80% of the N, 60-85% of the P and 80-90% of the potassium fed to animals comes back out in the manure. P is the big, bad wolf of the pollution woods. NRCS says that, although N and carbon compounds can cause problems, P is the main element that can be controlled and therefore help control eutrophication in fresh water. Eutrophication is the natural aging of lakes or streams brought on by nutrient enrichment.

When large amounts of nutrients such as P speed the eutrophication of surface waters, it can cause fish kills, reduce biodiversity, create bad taste and odor in drinking water, increase water treatment costs and encourage growth of toxic organisms. P is of particular concern because plant growth in fresh water is often limited or encouraged by P levels.

The solution

Generally, the more crop you can harvest and remove from a land application site, the more P and other nutrients you will remove. A big crop will remove more nutrients than a small one. Wheat plus the wheat straw will remove more nutrients than just the grain. A two-crop rotation of warm- and cool-season plants will remove more nutrients than one crop per year.

That's why multiple cuttings of alfalfa or double cropping of silage or haylage are popular cropping schemes on the land application sites for CAFOs whose nutrient output and uptake are already regulated.

Larry Poindexter, NRCS nutrient management specialist in Stillwater, OK, says this holds true. “More of the applied nutrients are generally taken off if you can remove them in hay or grain and take them offsite.”

A smorgasbord of pollutants

Phosphorus (P) is not the only potential pollutant emanating from CAFOs. Nitrogen (N), although much more mobile and more volatile than P, can nonetheless become a problem. It's easily transported in water, but removing it requires additional and expensive treatment beyond the normal purification processes.

N from manure is available in several forms, but especially as ammonia and nitrate. Large amounts of N in bodies of fresh water can reduce dissolved oxygen levels and therefore the ability of the water to support life. Excess ammonia can also cause eutrophication. Excess nitrate can be hazardous to humans drinking that water.

Organic matter is a problem in surface water because it's decomposed by aquatic bacteria and other microorganisms, a process that consumes oxygen.

Dissolved solids, including such things as manure, bedding, feed, hair and feathers, increase the turbidity of water and physically the function of desirable aquatic plants and animals. Pathogens and odorous/volatile compounds may also cause problems. Solids that settle to the bottom can damage the habitat for some species of fish, shellfish and other aquatic life. Further, solids can serve as a transport mechanism for the accumulation and transport of other pollutants.

Disease-causing microorganisms, including bacteria, viruses and parasites, are another form of pollution that comes from CAFOs. In its final report on the new CAFO rules, EPA noted that more than 150 pathogens found in livestock manure are associated with risks to humans, including six human pathogens that account for more than 90% of food and waterborne diseases. Commonly recognized examples are campylobacter, salmonella and E. coli.

Concentrated animal wastes have also been shown to pollute waters with excess levels of salts, trace minerals, antibiotics, pesticides and hormones.

If you wish to gain a deeper understanding of ag runoff effects on bodies of water, try the “Agricultural Waste Management Field Handbook,” available online through the NRCS Web site at:

Another excellent source is “Agricultural Phosphorus and Eutrophication,” a booklet available through USDA-ARS, publication ARS-149. It is available through this Web site:

The dope on digesters

Anaerobic digesters are today's waste management star.

Anaerobic digesters are one of the hottest waste management technologies because they help with many of the problems CAFOs are facing, and may offer a return on investment. Anaerobic digesters are sort of lagoons with lids on them. Most are heated to speed the bacterial process.

The new farm bill made Environmental Quality Incentives Program (EQIP) money available through NRCS to help fund anaerobic digesters.

They apparently do a great job controlling odor, they dissolve more of the solids than simple lagoons and similar holding technologies, they destroy most pathogens, and they capture methane gas that can be used as a heat source or to produce electrical power. Still, their implementation is limited.

Specifically through a program called AgSTAR, a joint effort of EPA, USDA and the U.S. Department of Energy, there now are 31 anaerobic digester systems in operation at commercial livestock farms in this country. Fifteen are at swine farms, 14 are at dairy farms, and two are at caged-layer farms. Many were done in coordination with emerging state agricultural energy programs in Iowa, Minnesota and New York.

One of these is at Craven Farms of Cloverdale, OR. That operation finished a heated, unmixed, plug-flow digester sized for daily manure production of 1,000 cows in December 1996. The farm is currently producing about $24,000 of electricity and $30,000 of digester fiber yearly. The value of digested solids is twice the original estimates. The digester has eased manure handling and reduced the cost of application.

The total cost of the system, which was defrayed by several grants and by AgSTAR's technical assistance, was $252,848.

The installed cost for the systems listed on the AgSTAR Web site range from a low of $15,000 for a 3,000-pig nursery unit in Iowa that simply flares (burns off) its gas, to $546,000 for a 5,000-sow, farrow-to-wean Iowa facility that generates electricity. Some of the units flare all the methane produced. Others use some of the gas to warm water and/or air and then flare the excess. Still others generate electricity and heat. Obviously, the latter facilities have the highest payback, but also the highest capital investment.

In 23 of the 31 AgSTAR-aided systems, the captured methane is used to generate electrical power and heat. Although electrical generation has up to now required a fairly large volume of methane to run an internal combustion engine, pending research at the USDA-ARS research station at Beltsville, MD, might yet show the value of micro-turbine engines for the same purpose from much smaller operations.

Anaerobic digestion converts much of the organic nitrogen into ammonia, which offers an advantage. The resulting effluent of 60-80% ammonia is preferable for managers who need to calculate and track nutrient application rates, says Mark Moser of Resource Conservation Management, Inc., Berkeley, CA. Nitrogen availability is more predictable in ammonia than in organic matter.

Smithfield Foods, the nation's largest pork producer, has for several years been experimenting with anaerobic digesters. It will soon complete in Utah an anaerobic digester facility to turn the waste from 257,000 pigs into biomethanol. Then, through a patented process, the company will combine the methanol with oil and market it as biodiesel.

Garth Boyd, director of environmental technology for the company, says he looked at hundreds of technological innovations over the past few years and believes this route has the best combination of attributes, including the payback.

Boyd says Smithfield began experimenting with anaerobic digesters in large part for odor control. The opportunity to gain the other advantages, however, makes anaerobic digestion an attractive technology.

The payback from electrical generation depends to a large degree on the location, Boyd adds. Some states require buyers and sellers of electrical power to offer better rates for “green” or non-fossil fuel energy. Others don't, and the payback is usually much poorer.

Despite Smithfield's size, its interest in the new technology and aggressive plans for large new facilities, its use of anaerobic digester technology is still fairly limited. Boyd says only 10 of the company's 2,000 farms have digesters that actually capture methane and do something with it.

Digesters cost more to build, per unit of volume, than lagoons, but a heated digester requires a much smaller volume than a lagoon. Construction costs vary among regions, soil types and digester types. Costs cited in recent AgSTAR projects, minus gas use costs such as generators, showed these results:

  • Unlined lagoon construction cost 7¢/cu. ft., while a HDPE-lined lagoon costs about 16¢/cu. ft.

  • Concrete tank digesters, including boilers to maintain digester temperature, cost $1.90 to $2.25/cu. ft.

  • A digester project using a clay-lined, partially concrete-lined lagoon cost about $1.09/cu. ft.

A lagoon system requires 20 times the volume as a heated digester to achieve the same level of treatment, and that investment could be transferred into digester construction, Moser says. Therefore, for comparable levels of biological stabilization, an operator would spend about $1.40 in an unlined lagoon; $3.20 in an HDPE-lined lagoon; $2.25 in a structural tank digester that is heated and mixed; and $1.09 in a heated, mixed, covered, lined-lagoon digester, he says.

Some good information on anaerobic digestion technology and resources is available through the home page of the AgSTAR program:

PAM and pellet solutions

There may be another commercially viable solution to the N and P puzzle. Successful research at the USDA-ARS Coastal Plains Soil, Water and Plant Research Center at Florence, SC, has recently been licensed to commercial operations. In its two forms, it has the potential to essentially stabilize nitrogen compounds and remove phosphorus in one of two forms that are more commercially saleable than raw sludge.

Scientists at the research station adapted Japanese technology for treating municipal wastewater, explains soil scientist and station research leader Patrick Hunt. The process treats lagoon effluent by running it through a nitrifying chamber that has large populations of bacteria entrapped in polymer gel pellets. These break down the volatile ammonia into nitrite, then more stable nitrate. This process is known as nitrification.

Then, in a process called denitrification, the nitrate is converted to nitrogen, an odorless gas that's the largest component of air. Denitrification needs two conditions: a source of carbon and an anaerobic environment. These conditions are typically found in wetlands or liquid manure storage units.

Another system eliminates the lagoon entirely. It uses a flocculant called polyacrylamide (PAM), together with a screening system, instead of a lagoon to remove the solids. Then it uses the same nitrifying-denitrifying sequence to change the nitrogen. The combined technology of PAM and the pellets lowers nitrogen concentration in the remaining effluent from 675 parts per million to fewer than 25. That water, now purified and deodorized, can be reused to clean the hog houses or for crop irrigation.

Both systems also kill nearly all the pathogens by raising the pH to about 10.5, Hunt says. During this process, the remaining phosphorus is converted to calcium phosphate, which is then recoverable and saleable to the nutrient industry, Hunt adds.

For a look at this technology, see the USDA-ARS website for the Florence research station and select “animal waste treatment.” That Web address is:

Turning up the heat

Anaerobic digesters come in many varieties but one of the important distinctions is the heat range at which they operate. The hotter they run, the faster they change nutrient composition.

  • Ambient or unheated digesters use no heat other than what they generate on their own.

  • Mesophilic digesters operate at 37° C (about 95° F).

  • Thermophilic digesters operate at 55° C (about 135° F).

Web resources

Lengthen lagoon life

Lagoons for large-scale CAFOs would seem to be old technology by now, but they still hold some secrets. One is how long they should work effectively before sludge accumulates to the point where they require cleanout.

Although large-scale animal waste lagoons would seem to follow in the footsteps of municipal lagoons, they really don't. They're deeper and therefore more anaerobic and they carry much higher nutrient loads per given amount of volume, explains Doug Hamilton, Oklahoma State University waste management engineer.

All the engineering estimates for life of a lagoon are based on a series of measurements taken in South Carolina research about 1985, and although those estimates have been surprisingly accurate, they don't always work out. For example, inefficiencies arise in lagoons when too much sludge accumulates or when fluid levels are drawn too low.

An example of their uncertain behavior is seen in research Hamilton has been conducting on two nearly identical swine lagoons in Oklahoma since 1995. One has followed the normal sludge accumulation pattern shown in the South Carolina study, with buildup to the seventh year, then a slowdown after that. The other has accumulated about one-third as much sludge. The difference in the two lagoons: The one with higher accumulation had the sludge disturbed by running the irrigation pump near the bottom.

Hamilton says it's too early to know the exact implications of this project, but disturbing the sludge may disrupt the bacterial action of a lagoon. Based on all the evidence to date, he makes two suggestions for CAFO operators using lagoons:

  1. Stick with the design standards for size and loading to avoid problems.

  2. Don't stir the sludge.

The design standards may not be perfect, but they still appear to be the best thing out there, and the tendency of many operators to skimp on size won't make a lagoon work any better.