• Will each load of biosolids delivered to the farm be tested?
• If each load of biosolids are not tested, how do we know that the generator or hauler is not bringing in a "hot load", contaminated purposely with a toxic chemical?
• Are there odors associated with the use of biosolids, or with facilities which process biosolids into other products?
• Are crops grown on biosolids safe for human consumption?
• Can crops grown on biosolids be sold on the open market?
• What are the heavy metal standards?
• Who controls how much biosolids are applied to the land?
• When can biosolids be applied?
• Who does the testing of biosolids, and who pays for that testing?
• Who is liable for problems, and does the State have a program to indemnify townships, participating farmers, etc.?
• Are the standards regulating the use of biosolids subject to change?

Will each load of biosolids delivered to the farm be tested?

In general, the answer to this question is no. Biosolids are delivered in 6-1000 gallon loads when liquid, and 20-30 cubic yards at a time when brought in as dewatered biosolids, compost or advanced alkaline stabilized sludge (AASS). It would be difficult and very expensive to test each load, and the testing takes several days to weeks to complete, so the biosolids would need to be held separately prior to application.

Biosolids are tested every four months following the first application by the permitted operator, and these analyses are submitted to the appropriate regulatory agency. The agency issues an approval which states that the biosolids meet heavy metal and organics quality standards, and whether the material meets the minimum requirements for stabilization. The applier or processor of the biosolids makes additional tests of the material during permitting before utilization. As part of the permitting process, the permittee must include 3 chemical analyses of the material from each sewage treatment facility or other source. A good biosolids recycler looks for material which is consistent in quality. By looking at 6-12 months of biosolids data, one can determine if the material routinely meets applicable standards, or if the quality is more variable. If the product is of variable quality and sometimes exceeds the allowable concentrations of some chemicals, more care must be taken in using these biosolids in direct land application.

If each load of biosolids are not tested, how do we know that the generator or hauler is not bringing in a load contaminated with a toxic chemical?

There are some safeguards against this occurring, but most rely upon the honesty of the generator, hauler or land applier. The regulatory agency makes routine, unannounced inspections of land application or biosolids processing facilities. They can, and do, take samples during these visits. There is no particular advantage to an unscrupulous waste hauler to try to dispose of illegal wastes at a biosolids management site. Such sites are regulated and regularly inspected, most of the operators of the sites haul as well as apply the biosolids. If they contaminate the site, they will be losing an outlet for the biosolids they are contracted to manage. It is unlikely that the profit they would make from illegally disposing of a chemical would make up for the loss of the site for biosolids management.

When biosolids are land applied, often the land owner is different from the biosolids applier. Frequently, these land owners are farmers, who derive the majority of their income from producing crops. There would be no incentive for them to contaminate their land, and often the agreements with the biosolids appliers require the applier to clean up the soil should some contamination occur. In addition, the land owners often do independent testing to insure the results being submitted by the biosolids generators or land appliers are accurate. Lastly, under current regulations, soil and groundwater testing are done routinely by certified laboratories. Such testing can act as the final check that no illegal disposal has taken place and contaminated either the soil or the groundwater.

Are there odors associated with the use of biosolids, or with facilities which process biosolids into other products??

The short answer is yes, there are odors associated with even well run biosolids facilities. These odors are generated by the application and processing of biosolids, but when properly operated, such odors should not be long-lived nor at levels which would be a nuisance for adjacent property owners.

The actual odors have been described as 'musty", or 'earthy', when describing the injection of liquid biosolids or the application of compost. Ammonia odors are associated with AASS or lime stabilized biosolids, often because the chemical reaction of the lime and the biosolids drives off the ammonia. Composting facilities will also have an earthy odor associated with them, and may sometimes smell like a wastewater treatment plant, depending upon the type of process used to compost the biosolids and the degree of air pollution control equipment installed at the facility. The odors associated with normal farm application of animal manure, especially when surface applied, are much worse than those caused by well operated biosolids facilities.

The surface application of liquid or dewatered biosolids or poorly cured AASS can cause off-site odor problems. Even well operated processing facilities will sometimes experience operational upsets which will cause odors to leave the immediate vicinity of the site. Rapid and complete incorporation of the biosolids on the day they are applied, or the use of lime over the applied biosolids, will reduce the odors from surface application.

When a facility is sited or constructed in a town where homes are in close proximity to the site, the operator, residents and township officials must come together to address resident's concerns over potential odors, and to set up a mechanism for the residents and operator to work together when odor problems occur. This could be as informal as the operator providing the residents with phone numbers and contact persons at the plant to call when problems occur, or as formal as a Citizens Advisory Committee (CAC) which would oversee the operation of the facility and which would react to citizen complaints of odors.

Are crops grown on biosolids safe for human consumption?

When the biosolids used to fertilize a food crop meet the EPA standards for heavy metals and destruction of pathogens, that crop is safe for human consumption. Current Federal standards have no restrictions as to what crops may be grown when a biosolid meets the Exceptional Quality and Class A Pathogen Reduction standards found in 40 CFR Part 503. Materials such as compost, or the AASS material which meet this standard, could be used to grow any crop consumed by humans.

Much research has gone into examining how food crops are affected by biosolids application. Where pathogens have been destroyed, such as through composting, and heavy metal levels are at or below the Exceptional Quality standards, there is no contamination of the edible portion of the crop through the use of biosolids. It may be of interest that many commercial fertilizers used by farmers and home gardeners contain levels of heavy metals similar to or greater than those found in biosolids meeting the Exceptional Quality standard.

Can crops grown on biosolids be sold on the open market?

Current Federal standards allow the sale of crops grown on biosolids, with restrictions being based on the quality of the biosolids. When biosolids meeting the Class A Pathogen Reduction and Exceptional Quality metal standards are used, there is no restriction within the Federal regulations on the use of the crop.

Some standards restrict crops to non-food chain crops, such as hay or straw, or to crops which are processed before being eaten, such as vegetables going to a processor, or foods which would not be eaten raw by the consumer. Often, biosolids may not be applied to areas where tobacco is grown or will be grown and areas where root vegetables or vegetables which are eaten raw will be grown within 2 to 3 years. This restriction is for biosolids which do not meet the Class A Pathogen Reduction standards, but which do meet the current standards for heavy metal quality.

What are the heavy metal standards?

Below is a table showing current Federal standards, for the heavy metals regulated by the Federal 503 standards.

Metal	Federal 503 Exceptional	Federal 503 Maximum
Arsenic	41	75
Cadmium	39	85
Copper	1,500	4,300
Mercury	17	57
Molybdenum	n/a	75
Nickel	420	420
Lead	300	840
Selenium	100	100
Zinc	2,800	7,500

Who controls how much biosolids are applied to the land?

The Regulatory Agencies, through permits issued to biosolids management facilities, set limits for the application of biosolids. These limits are based either on the yearly loading of metals, available nitrogen, or soil lime requirement, depending on the type of biosolids being used. The most restrictive requirement is the one which limits biosolids application.

In most cases, biosolids application is limited by the amount of nitrogen needed by the crop. This requirement is based on soil type and recommendations contained in the Rutgers Cooperative Extension Service Field Crop Guide. Here, biosolids are being used in place of commercial fertilizers. When biosolids, such as compost, are used in land reclamation, application rates are higher but application is limited to a one-time use. For AASS, which is used in place of agricultural lime, the lime needs of the soil, based on soil pH, are used to determine application rate.

When can biosolids be applied?

Regulations vary from state to state, but usually liquid and dewatered biosolids used in place of commercial fertilizers must be applied during the growing season, roughly March 1 to November 15, depending upon where the site is located. These materials cannot be applied to frozen or snow-covered ground, or immediately after a heavy rain when the soil is saturated. Products, such as compost or AASS, may be applied year-round so long as the application does not result in excessive runoff. These products may be applied in the winter, and may be applied to frozen ground. They are treated like any other agricultural products for which they are a substitute.

Who does the testing of biosolids, and who pays for that testing?

The testing required by the permits for biosolids management facilities require that the testing be done by State certified laboratories, and the testing is paid for by the permitted site operator. The regulatory agency may collect samples during their routine inspections, and these samples are analyzed by them in-house.

Who is liable for problems, and does the State have a program to indemnify townships, participating farmers, etc.?

Should a problem occur, such as odors, groundwater contamination, or some other violation of the permit, the permittee is responsible to correct the problem. Depending upon how the problem occurred, the permittee may also be fined or otherwise prosecuted by the regulatory agency. With respect to indemnification, there is currently no program that would indemnify the township where a facility is located, nor which would protect landowners participating in a beneficial reuse program.

It is noteworthy that most beneficial use projects are substituting biosolids for other agricultural chemicals, such as inorganic fertilizers. The use of these products is not regulated, and in many cases these materials contain heavy metals at levels similar to or higher than biosolids. When used as a fertilizer, biosolids actually pose a significantly lower danger to the groundwater, particularly from nitrogen contamination. Much of the nitrogen in biosolids is in the organic, or slow release form. This form of nitrogen is released slowly over the growing season, and is not as subject to leaching as inorganic nitrogen fertilizers. The organic matter in biosolids also reduces nutrient leaching, binds heavy metals present in the soil and biosolids, and improves soil texture and water holding capacity.

Are the standards regulating the use of biosolids subject to change?

The biggest change was be the adoption of the Federal biosolids management regulations, 40 CFR Part 503. These regulations, which were established using environmental and health risk based assessments, provide a scientific basis for the use of biosolids throughout the United States.

When used in land reclamation or in agriculture at rates based on crop nutrient needs, biosolids will not harm the environment or impact human health. There is extensive research establishing that the long-term use of biosolids is safe and will not cause degradation of ground or surface waters, soils, will not adversely affect crops grown on these soils, nor affect animals fed the crops or grazed on land where biosolids were applied.

Like any chemical used in production agriculture, biosolids must be used in accordance with sound agronomic practices and must meet the standards set by the Federal and State government if it is to remain safe and effective. Federal regulations set down minimum requirements for quality and management techniques, and the states can impose more stringent requirements to meet special circumstances or concerns within a particular region.