During the past two decades, pork production in the United States has grown in numbers only slightly. However, there has been a shift in both where these animals are grown and how they are grown. There is still a high concentration in the traditional Midwestern Cornbelt, but there has been rapid growth in the Southeast, especially North Carolina. Most animals are raised in specialized production facilities designed as environmental growth chambers. This presents both an environmental improvement over the era of animals in outdoor lots with uncontrolled odors, runoff and parasites, but at the same time new challenges of dealing with concentrated accumulations of manure in a sustainable manner. Pork production is becoming increasingly integrated where private landowners contract with a company to provide the land, facilities, utilities and labor in return for a fee to finish the companies? animals to market weight. As a result, farms tend to be larger, less diverse, and more densely centered around the companies? support facilities such as feed mills, processing plants, and farrowing and breeding farms. At the same time poultry production in North Carolina has shown growth although not at the rate of pork production.

The population demographics of North Carolina are also changing with more people relocating into the state particularly along the coastal corridor and in the western mountains. With an increasing population, more people wish to live in a rural setting. This increasing mix of farm and non-farm residents inevitably brings about discussion, debate and conflicts about the local environment. Many special agendas tend to get rolled into one environmental debate about livestock production. Misconceptions and misinformation can arise from this complex discussion. This article will attempt to use science to address some of these issues particularly about livestock manure management technologies and their measured impact on the environment.

ISSUE 1: What is a Concentrated Animal Feeding Operation (CAFO) ?

RESPONSE: An Animal Feeding Operation (AFO) is defined by EPA as a lot or facility (other than an aquatic animal production facility) where the following conditions are met :

     1) Animals (other than aquatic animals) have been, are, or will be stabled or confined and fed or
          maintained for a total of 45 days or more in any 12-month period, and
     2) Crops, vegetation forage growth, or post-harvest residues are not sustained in the normal growing
          season over any portion of the lot or facility.

An animal feeding operation (AFO) is a Concentrated Animal Feeding Operation (CAFO) subject to the NPDES regulatory program if any of the following criteria are met :

     1) More than 1000 animal units are confined,
     2) More than 300 animal units are confined and either one of the following conditions are met:
          a) pollutants are discharged into navigable waters through a man-made ditch, flushing system,
               or other similar man-made device, or
          b) pollutants are discharged directly into waters of the United States which originate outside of
               and pass over, across, or through the facility or otherwise come into direct contact with the
               animals confined in the operation, or
     3) Any operation which the permitting authority designates on a case-by-case basis.

However, no animal feeding operation is a concentrated animal feeding operation if such operation discharges only in the event of a 25-year, 24-hour storm event.
 

ISSUE 2: What is the difference between an animal unit and animal threshold numbers ?

RESPONSE: The term, "animal unit" (AU), refers to a unit of measurement to administratively compare sizes of animal feeding operations among different species of animals.  It was defined by the U.S. Environmental Protection Agency in 1976 for the purpose of administering the federal National Pollutant Discharge Elimination System (NPDES) regulatory program.  One animal unit is determined by multiplying one animal or bird by the following factor:
 

"Animal threshold number" is the population or number of animals on-farm which subjects that farm to the regulatory terms of the Water Quality Nondischarge Rule for Livestock Farms in North Carolina.  This state rule was adopted by the North Carolina Environmental Management Commission in 1992.  The animal threshold numbers in North Carolina are:
 

ISSUE 3:Are hogs raised in industrial warehouses or factories representing cruel and
Inhumane treatment of animals ?

RESPONSE: NO.  A factory is a building in which things are manufactured, i.e., the making of goods and articles by hand or by machinery.  A warehouse is a building where wares or goods are stored or kept in reserve.  These terms hardly seem appropriate to describe a livestock barn where food animals are born, are cared for, thrive and grow to maturity as living creatures before being transported to market.

Food animal production systems evolve through years of scientific research, adoption of research results, actual farming experience, and a continuing search for new and better methods.  These production systems are developed with input from a wide group of individuals with diverse backgrounds in the agricultural, biological, and social sciences; economics and business; and from landowners, farm operators, and farm workers.  Four objectives guide system development:  productivity, profitability, responsibility, and stewardship.

During a span of 30 years, production methods have evolved from uncontrolled, labor-intensive, outdoor systems where pigs were subjected to widely fluctuating extremes in weather; exposure to predators, parasites and disease organisms in muddy lots; and poor feed efficiencies with pigs needing five or more pounds of feed to produce one pound of pork.  If the animals could spend every day outdoors in fresh air, sunshine and moderate temperatures on clean grassy paddocks, the food animal production systems would have evolved in that direction.

Since our world, however, is not always ideal, food animal production buildings have been planned to reduce the extreme effects on animals by being more than just a barn of wood, nails, tin and concrete.  Buildings designed by NCSU engineers are planned as controlled growing environments where the welfare of the animals is directly related to animal health and performance.  The animals live on slotted floors which serve to quickly separate the animal from manure and urine, maintaining a cleaner animal and a more sanitary growing environment.  The NCSU mechanical ventilation systems are designed to bring in outside fresh air from near the building roof, down to the animal growing area, through the slotted floor helping to keep it dry, to be exhausted from the building underneath the slotted floor.  Ventilation system designs vary.  Manure is collected in shallow concrete pits underneath the floors, either into liquid recycled from the lagoon surface which is replaced every week or onto concrete surfaces which are flushed clean every four to six hours.

These ventilation and manure management techniques help to replace the stale air, moisture, gases and dusts in the growing environment with fresh air.  Temperatures inside these buildings are moderated during extreme weather conditions by providing heat in the winter time for young pig comfort and a cooling mist in the summertime for larger animals.  Pen partitions are provided for mature animals to prevent fighting and to prevent those sows which have just farrowed from crushing some of their baby pigs when they lie down, as is often the case in uncontrolled situations.

The better the conditions for the animals, the better they will perform and the easier it will be to maintain good animal health with less medication.  Better living and growing conditions as compared to outdoor lots are reflected in lower animal death losses and higher feed efficiencies where three pounds of feed or less today will produce a pound of live hog.

By improving the environment within the buildings for the animals, workplace conditions for workers are also improved.  The recommended NCSU swine building and management plan has been documented here, in the midwestern U.S., in Australia, and in northern Europe as achieving the best indoor air quality for the animals and workers of any of the alternative methods currently available.

It is desirable for all farmers and companies involved in food animal production to use all of the latest technologies available to them for the care and husbandry of their animals.  Some do not.  Many of the production buildings being constructed today are not the proven designs and recommendations of NCSU engineers.

Good workplace conditions can result in workers taking more pride in their jobs and doing a better job of caring for the animals.
 

ISSUE 4: Does a farm with 10,000 hogs produce as much waste as a city of 40,000 people ?

RESPONSE: Since animal manure and human sewage are composed of many different compounds and parameters, no single number can accurately represent the human population equivalent of swine.  Each parameter represents a different equivalency factor, therefore a single number, without qualification, is irrelevant.

For example, one farm with 10,000 hogs produces the same volume of waste as a population of 550 people.  This statistic highlights the fact that people use significant quantities of water for showers, cooking, dishwashing, laundry, etc which becomes wastewater when mixed with sewage.

However, because of this water dilution, human sewage is less concentrated than animal waste.  On the basis of organics, one farm with 10,000 hogs produces as much BOD as a population of 46,000 people.  On the basis of nutrients, one farm with 10,000 hogs produces as much nitrogen and phosphorus as a population of  25,000 people.  On the basis of bacteria, one farm with 10,000 hogs produces as much fecal coliform bacteria as a population of 2,300 people.

These analyses compare the amount of unrecycled wastes leaving a residence with those leaving a hog production facility.  They do not take into account collection and treatment processes or the fact that cities have other sources of waste from businesses and industries besides residential sewage.
 

ISSUE 5: Are livestock farms destroying our environment ?

RESPONSE: There are a number of reasons to support the premise that animal agriculture is NOT destroying our environment,  Livestock farms must accept their share of the responsibility, however, along with the rest of North Carolina’s citizens for the state’s environmental disturbances

The N.C. Cooperative Extension Service conducted a survey in 1990 where over 9,000 drinking water wells were analyzed.  A total of 3.2% of the wells tested had nitrate-nitrogen levels greater than the drinking water standard of 10 mg/L.  The only cause-and-effect relationships that could be verified were well construction, well-head protection, and well depth.

In 1995-96, a statewide total of 3,163 wells were tested by the N.C. Cooperative Extension Service, 1,137 of which were in the Coastal Plain.  A total of 3.5% of the Coastal Plain wells had nitrates higher than the standards.  All but 3 of these wells with high nitrates were less than 50 feet deep.  No well over 100 feet deep tested high in nitrates.  Two hundred of these wells in Sampson County were the same wells tested in 1990 and the nitrate levels were not significantly different.

A recently completed U.S.Geological Survey study reported that of shallow ground-water samples collected from 49 wells throughout the Coastal Plain of Virginia and North Carolina, 4 percent exceeded the 10-ppm drinking-water standard for public water supplies.

Four different national drinking water well surveys of all states indicated a percentage of wells with nitrate levels above the standard ranging from 1.2% - 4.9%.  Seven Midwestern states indicated a range of 19% - 71% of the wells surveyed had nitrates higher than the standard.

In 1997, 30 wells in Sampson County, NC suspected of nitrate contamination were analyzed with stable nitrogen isotopic tracer techniques to determine the source of nitrogen.  The intensive study concluded that commercial fertilizer, septic systems, and naturally occurring soil organic nitrogen were identified as the primary sources of nitrate in all 30 wells.  Animal waste was suspected of contributing minor secondary sources of nitrate in six wells.

A 5,000-acre watershed in Duplin County, NC was one of the first of 16 USDA Water Quality Demonstration Projects nationally whose objective was to accelerate the voluntary adoption of best management practices for water quality protection.  This watershed encompasses a broad mix of rural land uses which includes 120 farms and 200 residences.  Corn and soybeans are the principal field crops, but area producers grow at least 10 other crops of significance.  Livestock operations include about 24,600 hogs, 48,000 turkeys, 130,000 broilers, and 110,000 pullets.  Swine animal numbers have doubled since 1990.  Throughout the 8-year project period starting in 1990, the total nitrogen concentration in surface waters has been reduced by 1.5- to 2-fold as measured at the outlet of the watershed despite the increasing animal enterprises.  This continued reduction of nitrogen and slightly decreasing total phosphorus concentrations at the watershed outlet indicate the water quality benefits of BMP implementation and landscape modifications, including an in-stream wetland and riparian area restorations.  Biological monitoring shows streams in the study watershed have gone from fair to good/fair in a rating system that ranges from poor to good.

Most of the publicity about surface water pollution and remedial efforts have focused on one river in N.C., the Neuse River, a river that has a long history of water quality problems.  Dating back to the 1960’s and before, this river has experienced fish kills during the Fall due to low water flows, salt water intrusion from the estuary near its mouth, and nutrient enrichments from several sources including 6 major towns and cities, several community package treatment plants, and agriculture; all of which contribute to low oxygen levels in the river.  The watershed does not include the largest livestock growing counties of the state, and has relatively little animal agriculture near its headwaters.

A 1998 report from the U.S. Geological Survey states that concentrations of phosphorus and nitrogen have generally declined since 1980 in streams draining into the Albemarle and Pamlico Sounds in North Carolina.  Although nutrient concentrations in the Tar and Neuse Rivers in recent years have been linked to agricultural sources, the report presents evidence that natural geologic sources of phosphorus increase the problem in these two basins.  One of the nation’s largest phosphate mining operations is located in the Albemarle-Pamlico drainage basin.

At an early 1999 seminar a group of some of the state's leading marine scientists and biologists reported on findings from recent studies on water quality trends in the Tar-Pamlico and Neuse River Estuary Basins.  N, P, and chlorophyll a trends in the estuaries do not give clear evidence of increased eutrophication during the past two-to-three decades.  Since the late 1980's chlorophyll a appears to have decreased in the tidal freshwater portion of the Neuse estuary, but has shown no trend since the early 1970's in the middle and lower estuary.  Total N and P production from human-related activities in the Neuse and Pamlico watersheds increased substantially during the past 30 years.  Only 5-15% of the anthropogenic nitrogen produced in the basins reaches the estuaries (at least via surface runoff).  Even less of the anthropogenic phosphorus (2-7%) gets to the estuaries.  Apparently there is not a tight coupling between increasing nonpoint source nutrient production and patterns of nutrient concentrations in the estuaries.  For example, the great increase in animal nitrogen production in the Neuse basin seems not to have had an impact on nutrients or algal biomass (as measured by chlorophyll a) in the estuary.  This suggests there is a great "buffering" capacity in the watershed for this source.

Tour groups from all over the United States and several foreign countries have visited North Carolina during the decade of the 1990’s to learn more about its livestock production systems and associated environmental protection programs.  These visitors spend time with individual growers, livestock contract companies, citizens, researchers, regulators, and legislators.  They travel throughout North Carolina and visit the heaviest livestock producing areas of the state looking at the farms, visiting with the neighbors, judging the quality of our surface and estuarine waters, and taking the “sniff test”.  Visitors on these tours have overwhelmingly had positive things to say about North Carolina’s environment compared to what they had heard before their visit.

According to the N.C. Dept. of Commerce, tourism and the influx of people relocating to North Carolina has shown a steady growth trend during the 1990’s after a period of flat growth during the late 1980’s.  Most of this growth has occurred in the coastal corridor of eastern N.C. near the location of the hog production expansion and in the western mountains.

If the number of hogs in the U.S. today were all grown in outdoor lots similar to 1960’s technology, an estimated 14 million acres of land would be required.  Much of this land increase would have to occur in wild or marginal lands heretofore undeveloped.  The resulting manure and sediment pollution from these outdoor lots during rainfall would be much greater and less controllable than that from modern confinement production.  The total amount of land suitable for agricultural production is not increasing; therefore, existing land resources must be used more efficiently.  A recent study at Johns Hopkins Medical University concluded that if world population growth trends continue, global food production will have to double from what it is today by the year 2025 in order to have enough to feed everyone.

These facts are not intended to encourage complacency among livestock farmers or to relieve them of their continued responsibility to protect the environment.  They do point out, however, that by several indicators, this state’s environment compares very well with other regions of the world.
 

ISSUE 6: Are livestock owners and growers doing everything they can to protect the
environment ?

RESPONSE: Many producers are doing an excellent job of managing their livestock farms to be environmentally friendly.

Many others, however, leave substantial room for improvement regarding forward planning, scheduling of land application events, and overall facility management.  They must devote the same level of attention to proper manure management that they give to other aspects of  production such as feeding and caring for their animals.
 

ISSUE 7: What is the function of waste treatment lagoons ?

RESPONSE: Waste treatment lagoon designs are based on 40 years of research to optimize biological treatment processes similar to those that occur in a sewage treatment plant for BOD, odor and solids reduction.  The Biochemical Oxygen Demand or BOD, oxygen required by bacteria while stabilizing decomposable organic matter, of the incoming waste is reduced by 90%.  The resulting biosolids after biological digestion have much less odor and nitrogen content than the incoming untreated manure solids.  Because of larger capacities, lagoons are more adaptable to “shock” loadings and better able to buffer biological upsets offering better treatment reliability than smaller capacity treatment systems.  In addition to their treatment function, lagoons also serve as temporary storage until the treated liquids and biosolids can be land applied.  This temporary storage capacity allowed swine manure treatment lagoons to contain their wastewater during Hurricane Fran without releasing millions of gallons of untreated sewage.
 

ISSUE 8: Are waste treatment lagoons the same as “cess pools” ?

RESPONSE: NO.  Waste treatment lagoons are engineered structures used by livestock farms and municipalities to receive manure, sewage, or wastewater for biological treatment by beneficial bacteria. Lagoons built during the 1990’s are lined to minimize leakage and protect groundwater. Treated liquids and biosolids are pumped from the lagoon and applied as organic fertilizer to field crops and forages.

Cess pools are deep holes dug in the ground to receive drainage or sewage from a residence and infiltrate the untreated liquids into the soil.  They were used primarily by single-family households for waste disposal before the technology of septic tanks and drainfield trenches was implemented.
 

ISSUE 9: Do lagoons ever leak ?

RESPONSE: All lagoons, storage ponds, or holding tanks leak to some extent.  The extent of the leakage from earthen lagoons is highly dependent on the foundation soil materials.  Fine-textured soils such as clay tend to leak less than coarse-textured soils.

Liners are required in coarse-textured soils to minimize leakage.  Manure solids covering the bottom and sidewalls tend to reduce the leakage but do not form a complete seal.  Lagoons when first built may leak more than they do after these manure solids begin to plug the soil pores.  Properly installed liners required during the 1990’s reduce this leakage to a level considered to prevent contamination of the groundwater.

Membrane or synthetic liners and tanks constructed of concrete or steel are not leak-proof.  Geomembranes on a soil base can leak at the seams or at punctures during or after installation.  Concrete tanks are subject to cracks.  Metal tanks are subject to corrosion.
 

ISSUE 10: Are lagoons deliberately designed to maximize the emission
of ammonia into the air ?

RESPONSE: NO. The only design criteria for the treatment component of a lagoon is based on BOD or Volatile Solids loading rates for optimum bacterial digestion of the organics.  There are no design criteria used for volatilizing or releasing ammonia to the atmosphere.

Ammonia is released from open lagoon surfaces since it is a natural by-product of anaerobic biological decomposition of organic matter.  Efforts are underway to reduce or recover these atmospheric emissions and better understand their impacts.
 

ISSUE 11: Is there a routine recommendation that lime be added to lagoons to volatilize
more ammonia

RESPONSE:  NO.  The optimum pH range for anaerobic lagoon treatment is 7.5-7.8.  Most properly designed and managed lagoons normally operate in or near this range.  The vast majority of the total ammonia in this pH range is in the ionized ammonium form in solution.  Effective “stripping” or intentional release of gaseous ammonia to the atmosphere requires a much higher pH (9-12).  If the pH were raised above 9.0 by additions of lime, more ammonia would be emitted from the lagoon, however, large additions of lime would be required becoming a limitation on the amount of liquid and biosolids applied to cropland or forages to ensure that the soil pH remained optimum for crop growth.

The only time that it is practical to add lime is to an overloaded or older lagoon which has ceased to function properly because the pH has fallen below the optimum range or to a new lagoon during the first year of start-up to buffer the lagoon pH until bacteria get established for optimum treatment.
 

ISSUE 12: Have waste treatment lagoon research and design criteria considered odor
emissions and water quality ?

RESPONSE: YES.    Much of the early lagoon research in the late 60’s and early 70’s focused on reducing odor as the primary objective.  This research resulted from previous design criteria from the 50’s thought to be inadequate, resulting in undersized lagoons and more potential for odor emissions.  Today’s lagoon design criteria strike a balance between optimum odor control and minimum surface area collecting  rainwater, resulting in more land application challenges when the lagoon is pumped between rainfall events.

The purposes of a lagoon is to provide containment, treatment and temporary storage of waste organics and nutrients prior to land application at recommended rates to protect water quality.  Without lagoon or equivalent treatment, more livestock organics and nutrients from a given number of animals would have to be land spread, resulting in more nutrients that could potentially escape to the environment either by leaching to groundwater or by rainfall runoff into surface waters.

Much of the recent publicity about lagoons have focused exclusively on what they are doing to the environment.  There needs to be more said about what they are doing for our environment.  Currently available alternatives if applied only from a narrow perspective, may be even less environmentally friendly than lagoons.
 

ISSUE 13: Do emergency spillways in lagoon embankments encourage illegal discharges ?

RESPONSE: That is NOT a design intent.    Proper engineering design standards and specifications include an emergency spillway  in the aboveground embankment, dam or dike of any impoundment, freshwater or otherwise.  The spillway is part of the emergency action plan to protect the embankment in case of unusual weather-related events such as thunderstorms of unusual magnitude or hurricanes.  It is to allow the excess diluted liquid from rainfall events greater than the legal containment requirement of a 25-year, 24-hour storm to be released from the surface of the impoundment through a designed channel at controlled rates, to prevent loss of the entire dam.  It is legal to release any surface liquid greater than the 25-year, 24-hour storm.  It is illegal to release any contents of the impoundment prior to the storm or any rainfall less than this storm event, regardless of whether this discharge is through a pipe, over the top of the dam, or through a designed emergency spillway.
 

ISSUE 14: Did one lagoon failure in North Carolina release 35 million gallons of stored
swine manure into the Neuse River and kill 10 million fish ?

RESPONSE:  NO.  The rupture of the lagoon dam at Oceanview Farms, Onslow County, North Carolina  released 22 million gallons of biologically treated lagoon liquid and biosolids into the New River Basin (not to be confused with the Neuse River Basin) in June 1995 after a month of heavy rainfall determined statistically to have the equivalent of a 500-year return period.  Unlike the regulatory allowances for wastewater management from rainfall events greater than a 25-year, 24-hour storm, no such allowances exist for periods of chronic heavy rainfall.  An unauthorized alteration to the dam and an incomplete land application system were probable contributors to the failure.

Intensive investigation by teams of experts verified that the maximum capacity of the designed and constructed lagoon was 22 million gallons.  Of this total capacity, approximately 21 million gallons were lagoon liquid with 10% of the BOD load and 30% of the nitrogen load of the raw untreated manure.  The remaining 1 million gallons were biosolids left over after microbial treatment, some of which did not drain from the bottom of the lagoon.

After water quality investigations by the state Division of Environmental Management, the official report indicated a total of 5,000 fish killed by the lagoon spill.
 

ISSUE 15: Has technology for livestock production and waste treatment only been
developed for the large contract farms while ignoring the small independent farms ?

RESPONSE:  NO.  Technology for livestock production buildings and waste treatment was developed with the small farm in mind before the onset of larger farms.  The same unit design technology per animal is used today for all farms regardless of size.

Because of economies of scale and more stringent environmental regulations, larger farms are better able to afford today’s technology.  Increased regulation of livestock production is likely to hasten the trend toward larger, more specialized farms.
 

ISSUE 16: Do waste treatment processes cause organic matter and nutrients to disappear ?

RESPONSE:  NO.  Matter is not destroyed in any waste treatment process, aerobic, anaerobic, or otherwise; it only changes form.  The nutrients can change forms, such as organic nitrogen to nitrate nitrogen or to nitrogen gas.  Nutrients remain in the solids, the liquid, or release to the air in any treatment system.  Any near-term substantial volume reduction of matter is only accomplished by evaporation of water which requires substantial energy.
 

ISSUE 17: Can municipal and industrial waste treatment technology simply be transferred off-the-shelf to the farm ?

RESPONSE: NOT without adaption.  Many of the same biological processes used to treat municipal and industrial wastes are also used on the farms.  The treatment systems are, for the most part, different.  Underground collecting sewer systems and lift stations are used to transport the sewage and other wastes from residences, businesses and industries to a centralized treatment plant usually located in a flood plain.  This plant can treat large amounts of wastes before discharging the wastewater directly into rivers and streams.  Even though a large percentage of the pollutants have been removed, the volume is relatively high and the pollutant mass loading to streams can still be high.  For example, if a sewage treatment plant discharges 10 million gallons per day with a total N concentration of 10 mg/L, the mass loading to the river would be 833 lbs N per day or almost 300,000 lbs N per year.  The majority of the conservative elements such as phosphorus and metals end up in the sludge which is land applied.

The construction and operating costs are spread out over a substantial number of citizens who pay user fees.  These fees can be adjusted as needed to cover the costs of waste treatment.  Also, since the incoming sewage to the plant is highly diluted with water, the organics and nutrients are not highly concentrated.  Some of the mechanical components used to treat this diluted sewage will not perform satisfactorily for more concentrated animal wastes which use less water.  If not for the limitation of available land, more municipalities would consider a land-application-based treatment system generally regarded as more environmentally friendly than direct stream discharge.

Livestock farms are generally spread out over the countryside rather than being clustered together like a town or city.  Constructing and operating an areawide sewer collection system for the more concentrated manures is subject to leaks and spills and is neither affordable nor manageable.  Hauling manure slurries over the highway in tankers to a central treatment plant is equally unappealing, as has been proven in Europe.  Therefore, the treatment system technologies have to be scaled down to serve only the farm where the manure is generated and where the treated manure can be land applied to recycle nutrients for growing crops without a direct discharge into surface waters.  This makes the costs of using currently available municipal-type treatment designs unaffordable to the average farmer who has to bear all of the costs without being able to spread these costs over large numbers of users.  Individual farmers do not have the ability to adjust the prices they receive for their products to cover their operating costs.  More complex treatment systems on livestock farms also increase operator skills and/or the likelihood of operator error.
 

ISSUE 18: Is the application of livestock and poultry manure an appropriate use of land
resources ?

RESPONSE: In 1976, Menzies stated "The return of organic wastes to the soil is a part of the natural cycle.  No system that avoids or abuses this cycle can be considered permanent.".

Some elements such as nutrients, minerals and metals present in the soil are used to grow feedstuffs for livestock production.  Animals convert these feedstuffs, many of which (e.g., grasses) are inedible by humans, into protein.  Some of the nutrients are converted into meat protein, milk or eggs edible by humans while other elements are unused by the animal and excreted in manure.  These excreted elements are returned to the land for later use by the next crop reducing the amount of inorganic fertilizer nutrients needed to produce that crop.

In addition to the replenishment of soil nutrients by returning organic nutrients to the land, organic matter in manure is also added to the soil.  This organic matter enrichment improves soil structure and tilth.  Adding organic matter to tight clayey soils loosens up the soil and increases the water infiltration rate reducing surface runoff during rainfall events.  Organic matter in coarse textured sandy soils occupies some of the soil pore space and increases the soil water holding capacity.  This reduces water percolation out of the root zone and improves water availability to crops during dry periods.

Land application of livestock manure is but one example of how land resources are used beneficially to receive and utilize nutrients, minerals, metals and organic matter.  Municipal biosolids and industrial residues are often land applied; municipal and domestic wastewater are sometimes irrigated to golf courses and parks.  Inorganic fertilizers are applied to field crops, pastures, urban lawns and gardens.  Organic mulch and composts are applied to flower beds and landscaped areas.  In all cases, the application of these organic materials and by-products should be applied in quantities that do not exceed the needs of the receiver crops.  Waste matter does not disappear during a treatment process.  It must go into the air, water, or soil.  Why put potential pollutants into the air or water when they can be beneficially utililized on the land?
 

ISSUE 19: Is hog manure defined as a toxic and hazardous waste ?

RESPONSE: NO.  Livestock feeds are composed of feedstuffs such as corn and soybean meal, which are composed of carbohydrates, protein, fat, and some minerals.  In addition, a premix is added, which contributes calcium, phosphorus, iron and other minerals and vitamins in minute quantities essential for survival and growth.

Manure is mainly composed of microbes, microbial byproducts, and undigested feedstuffs.  Urine is mainly composed of water and contains metabolic byproducts such as urea.  Metabolic by-products of animals and humans must be handled properly since intestinal pathogens may be present and by-products of decomposition can accumulate in unhealthy concentrations under certain conditions.
 

ISSUE 20: Should all animal manure and wastewater be soil incorporated when land applied ?

Spreading time for a given volume of material is significantly increased compared to surface application or irrigation.  Since required nutrient management plans only allow a limited window of application, the increased spreading time may not permit all of the material to be spread at the most environmentally optimum time.  Soil injectors require more power using more fuel and increasing labor costs.
 

ISSUE 21: What are agronomic rates ?

RESPONSE: Agronomic rates are the application of fertilizer sources to soils to supply only enough nutrients to obtain good crop yields.  This optimizes crop production without degrading soil productivity or impairing water quality.  Agronomic rates are determined through soil testing, manure analysis, and knowledge of crop needs.  By rule in North Carolina, nitrogen determines the agronomic rate of application for livestock manures.  However, manures do not always provide a balanced blend of fertilizer nutrients for various crops.  Therefore,if manure is applied at rates to meet the nitrogen needs of the crop, it often provides other nutrients such as phosphorus in excess of crop needs.
The true agronomic rate would be determined by whichever crop nutrient need is met first by the manure application.
 

ISSUE 22: What is a 25-year, 24-hour rainfall event ?

Response:A 25-year, 24-hour storm is calculated by the National Weather Service and is defined by the Department of Commerce as the number of inches of rainfall in a 24-hour period that is expected to occur only once each 25-year period.  Since this is a statistical calculation, it does not mean that if such a storm event occurs, another one cannot occur for another 25 years.  Another one might occur the next day.  It simply means that on a long-term average, only one such event of this magnitude should occur in each 25-year period.
 

ISSUE 23: What are perennial streams and how are they defined ?

Response: Perennial streams are all waters of the state of North Carolina large enough to be indicated by a blue line on the most recent version of the United States Geological Survey 1:24,000 (7.5 minute) topographical maps.  The federal term in the NPDES regulatory program most analagous to this definition is "navigable waters".
 

Issue  24.  Does the indication of manure nutrient surpluses in some North Carolina counties imply existing water quality or other environmental problems in those counties ?
 

RESPONSE:  NO. Those involved in considerations for siting new proposed farms should consider the guidelines and standards which apply to that individual farm to minimize its off-site impacts.  In addition, the cumulative effect of increasing numbers of farms and animals within the boundaries of a watershed need to receive more attention.

Farming and waste treatment are not exact sciences.  Even if all the farms in the watershed were managing the manure and nutrients according to recommendations, the crops and grasses are not 100% efficient in using those nutrients.  A certain amount of nutrients, whether organic or inorganic, are unused by the plants and enter the environment.  As more farms are developed, more cumulative nutrients will be unused unless every inhabitant in the watershed finds a better way to use them.

Each watershed has a finite capacity to assimilate these unused nutrients in a sustainable manner.  This carrying capacity, dependent not only on the agricultural nutrients but every other source of nutrients, is difficult to precisely determine.  New farm sitings and other development must take into consideration what is already located in the watershed and whether or not more development will put undue burden on the environment’s assimilatory capacity.
 

ISSUE 26: Does the majority of potential odor from a hog farm originate during irrigation ?

RESPONSE: The presence or absence of odor during irrigation from a hog lagoon depends on whether the lagoon has been built and is being managed according to standards.  If it has been built according to standards and the liquid levels are being maintained according to recommendations, the odor from irrigating the liquid from this lagoon is the least likely of three potential sources on the farm; production facilities, lagoon, or irrigation.  At least one scientific study in N.C. supports this statement.

Irrigation odors can be detectable, however, during the early spring transition from colder to warmer temperatures.  Irrigation odors can also be detectable when pumping from an undersized lagoon, an older lagoon full of biosolids such that the incoming manure is not being properly processed, or on windy days with a high potential for transport of aerosolized drift.
 

ISSUE 27: Are unpleasant odors always associated with harmful health effects ?

RESPONSE:  NO.    There is a difference between an odor which is considered a nuisance because an individual doesn’t think it smells good, and gases, dusts or other compounds which, when inhaled in sufficient quantities, may have health effects.  Sometimes the perception of odors can lead to a health effect such as nausea.

Under extreme situations such as an enclosed tank where manure has been stored or is being agitated, hydrogen sulfide can be released from the stored manure into the air space near the inside top of the tank in lethal concentrations.  In outdoor unconfined spaces such as the edge of a lagoon or the property boundary, this same compound is diluted in air such that it may no longer be a health concern but may
present an occasional nuisance.

Dusts and other compounds when inhaled by workers spending several hours each day inside hog houses may present chronic health effects, but when exhausted outdoors and diluted by air may be only an occasional unpleasant odor.
 

ISSUE 28: Since the adoption of North Carolina's odor rules, have the odor complaints against hog farms been verified ?

RESPONSE: Between March 1999 when new enforceable state odor rules were enacted and July 2000, the N.C. Department of Environment and Natural Resources (DENR) received over 200 complaints, but only two could be verified by the Division of Air Quality under the rules.
 

ISSUE 29: Does the production of livestock contribute 50% of all ammonia emissions into the atmosphere ?

RESPONSE:  Generally YES.  Ammonia is a reduced form of nitrogen, which is common to living organisms.  Much nitrogen in the form of plant proteins is used to feed animals.  Part of this protein nitrogen is converted to meat, milk and eggs.  The remaining nitrogen is excreted by the animal as manure and urine which release ammonia.  Most world-wide efforts at nitrogen budgets assign animals (chickens, pigs, turkeys, cattle) with being responsible for 40% to 60% of atmospheric ammonia emissions.

Researchers recently presented evidence that cars may be the main source of haze-inducing ammonia, rather than livestock, as previously thought.  The findings were presented at the national meeting of the American Chemical Society in Washington, DC by a senior scientist at the Oak Crest Institute of Science in California.In a study of 4,500 vehicles, researchers found unexpectedly high levels of ammonia in the exhaust of gasoline-powered cars.  They estimate that cars are adding twice as much ammonia to the air of California's southern coastal basin as livestock do.  Until now, scientists believed that decomposition of livestock waste was the main source of atmospheric ammonia according to the principal investigator of the study.  Some theorize that reformulated gasoline, introduced in the mid-1990s to lower sulfur and other emissions, has contributed to the increase in ammonia levels.  Another published study reported that catalytic converters may play a role in rising ammonia emissions as well.  Aside from cars, and farm activities, another major source of ammonia emissions was sewage treatment plants.
 

ISSUE 30: How are these ammonia emissions from livestock being estimated ?

RESPONSE: There are some measurement data in the literature and scientists are also conducting limited measurements here in North Carolina.  Some type of factor is usually generated from these measurements that can then be used to estimate ammonia emissions from animal population statistics.  Unlike industries, extensive databases of actual measurements of ammonia emissions from animal production are unavailable.  The amount of emissions will also vary with type and size of the operation; e.g., cattle feedlot versus pasture, e.g., swine slurry manure handling systems versus liquid manure handling.  In more confined animal operations, the amount of feed and its nitrogen content can be used to calculate nitrogen inputs, and the nitrogen  composition of the animals and their products such as milk can be calculated for those outputs.  The difference between feed inputs and product outputs approximates the nitrogen excretion, which approximates an upper limit for potential ammonia, not the actual emissions.

ISSUE 31: How much of a problem are these ammonia emissions ?

RESPONSE: A most difficult question to answer.  The most honest answer is, we really don't know.  All aquatic and terrestrial systems require nitrogen to survive and function.  We know what happens under controlled experiments when nitrogen is added to aquatic or terrestrial systems.  In the real world, conditions are not very controlled.  Each aquatic or terrestrial system has an internal nitrogen cycle which dictates how nitrogen coming into a particular ecosystem is utilized, transformed and then possibly exported.  One way to look at the world around us is as a series of functional units with their own internal cycles communicating with one another via the inputs and exports.  During certain times of the year a given ecosystem may process nitrogen inputs differently than at other times of the year.

Ammonia emissions, whether from animals or industrial sources, must be viewed as adding to the loading of nitrogen that occurs to most aquatic and terrestrial ecosystems through wet and dry deposition.  The amount of nitrogen that is deposited in rainfall (wet deposition) and in dry deposition can be measured at point locations.  At this time, there is very little data on nitrogen loading from dry deposition.  Thus determining the impact of ammonia emissions on the North Carolina environment can be broken down into at least two different parts:  1) how much of the ammonia is actually being deposited into our different ecosystems?, and  2) once it has been deposited, how does the nitrogen cycle within each given ecosystem respond to this input?

Attempts are being made now to answer the first question by direct measurements and through the use of models.  Once a good estimate of ammonia loading into our aquatic and terrestrial ecosystems has been obtained, the knowledge base about nutrient cycling within these systems can be used in an attempt to answer the second and most important question, what is the effect or impact?  It would be very wrong, especially for terrestrial ecosystems, to use the data obtained in response to the first question as a direct measure of effect and skip the second question.

Will ammonia emissions from animal operations in North Carolina have an effect on our terrestrial and aquatic ecosystems?  Yes, because they add to the loading of atmospheric nitrogen to our ecosystems and every ecosystem will respond to this increase in loading.  Can we assume that every response to this increase in loading will be negative?  No.  Do we know how much of an increase in loading these ammonia emissions actually represent?  No, but information is being gathered.  Do we have the necessary knowledge about nutrient cycling to understand how these additional nitrogen inputs will impact our ecosystems?  No, since such knowledge comes from long term ecosystem level studies which are difficult to fund and do not produce high profile results.
 

ISSUE 32: Have gas emissions from livestock farms been proven to have caused large impacts on our environment ?

RESPONSE: Very little ground-truth data has been collected to date to verify the relative atmospheric emissions of various compounds or their environmental impacts.

Some livestock farm emissions such as methane, carbon dioxide, and nitrous oxide are thought to be contributors to the global “greenhouse effect”.  Some of the un-ionized form of ammonia is believed to contribute to rainfall deposition of atmospheric nitrogen.  Ammonia also transforms to the ionized form of ammonium which may combine with other pollutants such as sulfur compounds from power plants to form particulates.

Ammonium also combines with water to form ammonium hydroxide.  This weak base helps to reduce or mitigate the effect of acid rain.

Other emissions are known to be neutral to the environment such as dinitrogen or N2 gas, the same natural element that constitutes 78% of the air that we breathe.
 

ISSUE 33: Is there a direct linkage between livestock production and outbreaks of pfiesteria ?

RESPONSE: NO direct linkages have been scientifically documented between the production of livestock and outbreaks of the toxic dinoflagellate, pfiesteria.  It is suspected that eutrophication of surface waters, or the enrichment of these waters with nutrients, contribute to these outbreaks.  Scientists cannot link their presence or the emergence of toxic forms to any particular source of nutrients.  There are many sources of nutrient inputs to surface waters.  Livestock and poultry production are but two of these contributors.  Solving the nutrient enrichment issue may or may not resolve our concerns with pfiesteria.  According to a recently released U.S. Geological Survey report, nitrogen and phosphorus levels in the Neuse River have generally declined since 1980.  Any linkage between animal production and pfiesteria outbreaks at this point is more speculation than scientific fact.  The goal has been and should continue to be a long-term program for reduction of nutrients entering our water resources from the total watershed.
 

ISSUE 34: Has the incidence of hog-related infectious diseases increased during the recent
   growth of pork production in North Carolina in the 1990's ?

RESPONSE: Two medical doctors with the Division of Infectious Diseases at Duke University Medical Center, recently published a review of currently available information of hog-related infections in North Carolina.  All available data suggest that the risk of infectious diseases posed by the state hog industry, while potentially important, is limited primarily to pork production employees who may come into contact with brucella, Erysipelothrix, or S. suis.  The recent development of corporate hog farming in North Carolina has greatly increased the confined swine herd.  This has actually reduced the risk of hog (and presumably human) infection by T. gondii and T. spiralis.  Several hog-associated infections (toxoplasmosis, trichinosis) are less common in pigs raised in total confinement, but other human pathogens such as salmonella are still common in swine raised in modern facilities.  Available epidemiological data do not suggest any increase in the incidence of diseases caused by waterborne human pathogens such as salmonella or leptospira.  To maintain this excellent track record, future efforts to ensure the safety of pork should be directed toward controlling enteric organisms such as salmonella.

The annual incidence of human salmonellosis has remained constant during the recent expansion of the hog industry.  From 1989 to 1995, the hog population increased from 1.7 million to 7 million, but the annual incidence of salmonella infections reported to the Epidemiology Division of the Department of Environment, Health and Natural Resources remained unchanged.  Since 1989 the 11 leading hog-producing counties have contributed only 10%-12% of the annual total of reported salmonella cases: most cases occur in the populous urban counties.

Throughout the world, Brucella species cause serious systemic illnesses.  In the US, human brucellosis is rare and primarily affects livestock and abbatoir workers.  There is a national program to eradicate swine brucellosis.  This program locates and eliminates infected swine.  North Carolina's swine herd is considered brucellosis-free.  From 1977-92 and from 1994 until the present, 1-3 cases of human brucellosis were reported each year in North Carolina, and most of these cases probably arose from ingestion of unpasteurized foreign dairy products.

At the turn of the century, 1.41% of the US hog population was infected with the tissue-dwelling nematode, Trichinella spiralis, but the prevalence declined to 0.l25% by the 1970's, largely because of restrictions on the feeding of uncooked garbage to pigs and improved farm management.  Modern hog management practices in North Carolina have virtually eliminated the risk of swine infection with Trichinella.  For example, more than 2200 North Carolina hogs raised in either traditional or modern production systems were recently tested for antibodies to T. spiralis; only one hog (0.04%) was positive and this animal had been raised in a traditional dirt lot.  As a result of this drastic reduction in infected hogs, only two cases of human trichinosis have been reported in North Carolina since 1987.

In the early 1980's, 24% of a random nationwide sample of swine were seropositive for the intracellular protozoan, Toxoplasma gondii.  Since then several studies have shown that pigs raised in modern facilities using total confinement have a lower prevalence of toxoplasma infection  Modern hog management practices in North Carolina appear to have virtually eliminated swine infection by T. gondii.  Only 13 (0.56%) of more than 2300 North Carolina hogs recently tested were positive for antibodies to T. gondii, and 12 of them (92%) had been raised by traditional pasture methods.  Only one (0.05%) of the 1826 hogs kept in modern total confinement facilities was positive.

Human leptospirosis is rare; only 17 cases of human leptospirosis have been reported in North Carolina since 1977.  The annual incidence (0-3 cases) of human leptospira infections reported to the state has remained unchanged during the recent hog industry expansion.  There is no evidence to suggest that hog industry growth has increased the statewide incidence of human leptospirosis.
 

ISSUE 35: Are the incidence of the protozoan parasites, giardia and cryptosporidium, in streams and surface waters always linked to the presence of livestock ?

RESPONSE: Cryptosporidium made headlines in 1993 when it got into the Milwaukee water supply causing 100 deaths.  The illness lasts only a few days in most people with healthy immune systems, but those with severely weakened immune systems can develop life-threatening infections.  The source of the contamination of Milwaukee's water supply, which is drawn from Lake Michigan, was never determined. This parasite can be spread in a variety of ways, but always through fecal matter.  Cryptosporidium can infect and be shed by about 80 species of animals, including humans, cattle, sheep, goats, pigs, horses, dogs, cats, and various wildlife species, such as deer, elk, raccoons, opossums, feral pigs and rabbits.  Surveys indicate that cryptosporidium is common in untreated surface water throughout North America. Although cattle are often suspected as sources of cryptosporidium, studies have not established a clear link between livestock and the presence of the parasite in lakes and streams.  Surveys conducted by the University of California - Davis School of Veterinary Medicine show that in an infected cattle herd, only calves up to four months old shed cryptosporidium, while older cattle are not significant sources.  Making sure that young calves are not confined or do not graze near streams or reservoirs would eliminate most of the risk of contamination from cattle according to their surveys.

More than 100 outbreaks of water-borne giardia illnesses have occurred in the United States since 1965.  Most of these outbreaks have been attributed to contamination of surface water with human sewage.  Giardia is also commonly spread by direct person-to-person, fecal-oral transfer of cysts, and giardia outbreaks have been associated with poor hygiene or inadequate sanitary conditions in day-care centers, nurseries and public institutions.  Although giardia infection is common in a wide variety of wildlife and livestock species, there is considerable controversy over the issue of whether cysts shed by animals can infect humans.  The evidence for zoonotic transmission of giardia from animals to humans is circumstantial.

ISSUE 36: Can waste treatment and land utilization of organic nutrients be regulated with exact science ?

RESPONSE:  NO.    Management and treatment of organic materials is part of a dynamic process because of the constantly changing nature of biological systems.  What is true of the characteristics of a biological system today will be different tomorrow.  Science helps us to navigate through this biological system in the least intrusive way.

However, society or sectors of society cannot be regulated on the basis that the biology of treating waste or using organic nutrients to grow agricultural crops are exact sciences.  The difficulty of predicting the availability of organic nutrients for plant growth is an example of how factors including, but not limited to, climate, meteorology, soil type, topography, geology, plant variety and microbial populations, most of which are constantly changing, can influence the prediction.  Growing crops with commercial fertilizer is subject to many of the same changing factors.  In any given growing season, crop harvest yields and nutrient uptakes are no more predictable than the weather.

ISSUE 37: Is it reasonable to expect livestock farmers to achieve a zero-tolerance, i.e., absolutely no discharge of pollutants ?

RESPONSE:  NO.  It is virtually impossible to achieve a zero-tolerance or absolute no-discharge of pollutants in any sector of our society.  Municipal sewage treatment plants discharge BOD and nutrients every day directly into our streams and rivers.  Residential septic systems infiltrate wastewater from the septic tank into the soil/groundwater interface.  Urban lawns contribute leftover fertilizer nutrients and chemicals to streams during rainfall runoff events.  Vehicle greases and solvents are washed from paved parking lot surfaces during rainfall directly into streams.  Emissions from automobiles, power plants, and paper mills contribute to air quality degradation.  Animal agriculture and farming also can contribute to air and water quality degradation.  The best that society should expect is to reduce pollutants and off-site impacts to balanced, achievable levels until newer and better methods become available to be implemented by all.
 

ISSUE 38: What is the Smithfield Agreement ?

RESPONSE: On July 25, 2000, the North Carolina Attorney General and Smithfield Foods, Inc, and its subsidiary companies (Browns of Carolina, Carrolls Foods, Murphy Family Farms, Carrolls Foods of Virginia, and Quarter M Farms), agreed to a legally binding agreement to develop and implement new technology that will protect the environment and the economy.  Under the terms of the agreement, the companies will be required to pay $15 million to North Carolina State University for the development of new technologies to replace open-air lagoon and sprayfield systems.  Experts at NCSU will identify, develop and test environmentally superior technologies.  Five full scale projects will begin immediately with more to follow within six months.  The project completion date must not exceed two years.  Once new technologies are identified, companies will convert their facilities and phase out the current lagoons and sprayfield systems within three years.  Smithfield, the country's largest pork production company, will provide the technical and financial assistance needed for their contract farmers to convert to the new technology.

Smithfield and its subsidiary companies will pay $50 million over the next 25 years to enhance the environment.  The companies will take immediate action such as:  1) identify farm lagoons and buildings in flood plains and draw up and implement steps to protect the waters of the state, 2) identify "at-risk" (deficient site conditions or operating practices) facilities and draw up and implement plans to clean them up, 3) identify wetlands and natural areas located on farms and draw up and implement plans to protect them, 4) identify abandoned lagoons and draw up and implement plans to close them, and 5) adopt an accredited environmental management system for their facilities.  The companies will play a leadership role in enhancing the effectiveness of the Albemarle-Pamlico National Estuary Program and help establish a permanent program to protect water quality in Eastern North Carolina.

Up to $2 million may be used to implement and monitor compliance with the agreement.  Violations of the agreement are enforceable through the courts.
 

ISSUE 39: What is an ISO 14000 Environmental Management System ?

RESPONSE:  The ISO 14000 EMS is a QA/QC environmental management system based on a family of standards and guidelines. ISO is the International Organization for Standardization.  ISO 14000 grew out of ISO's commitment to support the objective of sustainable development discussed at the United Nations Conference on Environment and Development in Rio de Janeiro in 1992.  An environmental management system makes possible a structured approach to setting environmental objectives and targets, to achieving these, and to demonstrating that they have been achieved.
 

ISSUE 40: What is the Premium Standard Farms Environmental Trust ?

RESPONSE: On October 2, 2000, Premium Standard Farms with headquarters in Kansas City, Missouri, and its North Carolina subsidiaries (Lundy Packing Company, Dogwood Farms, Dogwood Farms II, L&S Farms, L&H Farms, and Carolina Farms), agreed with the North Carolina Attorney General to assist in the development of environmentally superior technologies to treat hog waste and to implement that technology on its hog farms within the state.  The agreement by the second largest pork producer in the country mirrors the one that Smithfield Foods announced in late July.  Together, Smithfield and Premium Standard represent over 75% of the hog farms in North Carolina.

In the agreement, Premium Standard and its North Carolina subsidiaries agree to help develop and implement new technology that will protect the environment and the economy.  The legally binding contract commits Premium Standard to undertake immediate measures to help protect the environment.  Under the agreement, Premium Standard will pay $2.5 million into a trust that will be used to help develop the technology, improve the environment and defray the costs to the State in implementing the agreement.  The agreement again places North Carolina State University in the pivotal role of identifying improved waste treatment technologies.  The agreement sets out a research and development effort to begin immediately and to be completed within two years.  The conversion process will not exceed three years.  The agreement commits the company to provide financial and technical assistance to its contract farms to implement the new technology.
 

ISSUE 41: Which treatment technology(ies) would you recommend today to completely
replace manure lagoons and spray irrigation systems on swine farms ?

RESPONSE: To-date, NO complete system or suite of technologies has been proven on a commercial farm scale to be both technically feasible and affordable for recommendation on swine farms.  Many alternative manure treatment and management technologies have been evaluated by universities, research institutions, and private businesses around the world over the past three decades.  Much has been learned about individual processes for treating manure and other organic materials.  Much has been learned about how to improve and make the systems that are currently used work better.  For example, some lagoons have been converted to covered digesters where the biogas is collected and used as an energy source reducing the potential for greenhouse gas emissions to the atmosphere.  Ongoing evaluations of private vendor technologies continue in the lab and on pilot installations. Many farm manure treatment alternatives are either less environmentally friendly than treatment lagoons and spray irrigation systems, are too complex to successfully operate, or are unaffordable to swine farmers and growers.  Most alternative treatment systems generate additional by-products.  These organic by-products lack developed markets to recover the processing costs and therefore often become just another, but more expensive, waste product.
 

ISSUE 42: Must we wait until everything has been researched and studied completely before
 we act on or recommend anything ?

RESPONSE: NO.  Research and science must be the foundation of our educational programs and of any informed decision-making.  Our recommendations must be based on peer-reviewed science to the extent that good science is available.  The higher the risk of making a decision or implementing a recommendation, the more the need is to be sure that research and science supports that decision.  We should use good science wherever and whenever we can find it.

There are times, however, when in order to keep situations from getting worse, we must make educated decisions without a fully researched or documented basis, or at best a very thin database.  These decisions should be based on background, training, experience and/or common sense without personal bias.  When such decisions are necessary, we must weigh the downside associated with a decision and hold any risks to a minimum.  Hopefully these decisions will keep us headed in the right direction until better research becomes available.  We cannot afford to sit back, however, and wait until everything has been studied completely before making an educated decision or implementing a recommendation when not doing anything would allow a situation obviously headed in the wrong direction to get worse.
 

EBAE 215-98

WQWM 185