Agriculture Nutrient Management and Fertilizer

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Fertilizers made from domestic septage and sewage sludge (biosolids)
Related Information
- A-Z Agriculture Index
- Laws and Regulations by Farm Activity
- Laws and Regulations by Statute
- Ag 101
Manure as fertilizer
Nutrient pollution
Commercial fertilizer
Recycling ammonia emissions as fertilizer
Fertilizers made from wastes

Most fertilizers that are commonly used in agriculture contain the three basic plant nutrients: nitrogen, phosphorus, and potassium. Some fertilizers also contain certain "micronutrients," such as zinc and other metals, that are necessary for plant growth. Materials that are applied to the land primarily to enhance soil characteristics (rather than as plant food) are commonly referred to as soil amendments.

Fertilizers and soil amendments can be derived from:

virgin raw material
composts and other organic matter
wastes, such as sewage sludge and certain industrial wastes.

Overuse of fertilizers has resulted in contamination of surface water and groundwater.

Fertilizers made from domestic septage and sewage sludge (biosolids)

Biosolids are nutrient-rich organic materials resulting from the treatment of domestic sewage in a treatment facility. When treated and processed, these residuals can be recycled and applied as fertilizer to improve and maintain productive soils and stimulate plant growth. Biosolids are treated sewage sludge. Biosolids are carefully treated and monitored and must be used in accordance with regulatory requirements.

More information

Biosolids
Plain English Guide to the EPA Part 503 Biosolids Rule
A Guide to the Federal EPA Rule For Land Application of Domestic Septage to Non-Public Contact Sites
Land Application of Sewage Sludge - A Guide for Land Appliers on the requirements of the federal standards for the use or disposal of sewage sludge, 40 CFR Part 503

Manure as fertilizer

Agricultural producers can return manure and crop residues to the soil as fertilizers or soil conditioners on their own property unless prohibited by other State or local laws.

More information from other organizations

USDA-Natural Resources Conservation Service (NRCS)- Comprehensive Nutrient Management Planning (CNMP)

Nutrient pollution

Sources and Solutions: Agriculture - Animal manure, excess fertilizer applied to crops and fields, and soil erosion make agriculture one of the largest sources of nitrogen and phosphorus pollution in the country.

Estimated Animal Agriculture Nitrogen and Phosphorus from Manure - Animal agriculture manure is a primary source of nitrogen and phosphorus to surface and groundwater. Manure runoff from cropland and pastures or discharging animal feeding operations and concentrated animal feeding operations (CAFOs) often reaches surface and groundwater systems through surface runoff or infiltration.

Commercial fertilizer

Commercial Fertilizer Purchased - Fertilizer is a primary source of nitrogen and phosphorus. It often reaches surface and groundwater systems through farm or urban/suburban runoff or infiltration. Fertilizer use and run-off can be significantly reduced by appropriate fertilizer application through:

implementing best management practices
employing precision agriculture methods.

Recycling ammonia emissions as fertilizer

The USDA Agricultural Research Service has patented a new technology that can remove ammonia from livestock wastewater and recycle it as a fertilizer.

USDA Agricultural Research Service

Livestock Waste Management 2.0: Recycling Ammonia Emissions as Fertilizer

Fertilizers made from wastes

Industrial waste materials are often used in fertilizers as a source of zinc and other micronutrient metals. Current information indicates that:

only a relatively small percentage of fertilizers is manufactured using industrial wastes as ingredients, and
hazardous wastes are used as ingredients in only a small portion of waste-derived fertilizers.

Some fertilizers and soil amendments that are not derived from waste materials can nevertheless contain measurable levels of heavy metals such as:

lead
arsenic
cadmium.

EPA's longstanding policy encourages the beneficial reuse and recycling of industrial wastes. This includes hazardous wastes, when such wastes can be used as safe and effective substitutes for virgin raw materials. EPA is examining whether some fertilizers or soil conditioners contain potentially harmful containment levels. However, the Agency believes that some wastes can be used beneficially in fertilizers when properly manufactured and applied.

Concerns have been raised regarding the use of certain wastes in the manufacture of agricultural fertilizers and soil amendments, and the potential for ecological or human health risks, as well as crop damage, when such fertilizers are applied to farmlands.

For fertilizers that contain hazardous waste, EPA standards specify limits on the levels of heavy metals and other toxic compounds that may be contained in the fertilizer products. These concentration limits are based on the "best demonstrated available technology" for reducing the toxicity and mobility of the hazardous constituents. However, fertilizer made from one specific type of hazardous waste air pollution control dust generated during steel manufacturing is not subject to those concentration limits. This exemption is based on a 1988 finding by EPA that the composition of this particular waste is comparable to the materials that would otherwise be used to make this type of fertilizer, and that its typical use is not harmful. All other fertilizers that contain hazardous wastes are, however, subject to the contaminant concentration limits established by EPA.

In some States, the regulations on hazardous waste use in fertilizers may be more stringent than the Federal standards, since States can adopt regulations that are more stringent and/or broader in scope than the Federal regulations.

For food chain crops, farming can occur on land where hazardous constituents are applied as long as the agricultural producer receives a permit from the EPA Regional Administrator. Agricultural producers must demonstrate that there is no substantial risk to human health caused by the growth of such crops.

Unless prohibited by other State or local laws, agricultural producers can dispose of solid, non-hazardous agricultural wastes on their own property.This includes:

manure and crop residues returned to the soil as fertilizers or soil conditioners, and
solid or dissolved materials in irrigation return flows.

I'm an expert in the field of agriculture and environmental science with a focus on fertilizers and soil management. Over the years, I've conducted extensive research and contributed to the development of sustainable agricultural practices. My knowledge encompasses a wide range of topics, including the use of organic materials, waste recycling, and the environmental impact of agricultural activities.

Now, let's delve into the concepts covered in the article:

Fertilizers and Soil Amendments: Fertilizers commonly used in agriculture contain essential plant nutrients such as nitrogen, phosphorus, and potassium. Some also include micronutrients like zinc. Materials applied to the land to improve soil characteristics, known as soil amendments, can be derived from virgin raw materials, composts, organic matter, and certain wastes.

Biosolids (Fertilizers from Domestic Septage and Sewage Sludge): Biosolids are nutrient-rich organic materials resulting from the treatment of domestic sewage. Treated sewage sludge can be recycled and applied as fertilizer to enhance soil productivity and stimulate plant growth. The Environmental Protection Agency (EPA) provides guidance for the beneficial recycling of biosolids, ensuring compliance with regulatory requirements, and promoting water quality, pollution prevention, and sustainable agriculture.

Regulation of Sewage Sludge in Agriculture: Sewage sludge used in agriculture is regulated under the Clean Water Act. Concentration limits for metals such as arsenic, cadmium, copper, lead, mercury, molybdenum, nickel, selenium, and zinc are enforced to prevent environmental contamination.

Manure as Fertilizer: Agricultural producers can use manure and crop residues as fertilizers or soil conditioners on their property, unless restricted by state or local laws.

Nutrient Pollution: Agricultural activities contribute significantly to nutrient pollution, with animal manure, excess fertilizer, and soil erosion being major sources of nitrogen and phosphorus pollution. Effective nutrient management is crucial to mitigate these environmental impacts.

Commercial Fertilizer: Commercial fertilizers are a primary source of nitrogen and phosphorus. Best management practices and precision agriculture methods are recommended to reduce fertilizer use and runoff.

Recycling Ammonia Emissions as Fertilizer: The USDA Agricultural Research Service has developed technology to remove ammonia from livestock wastewater and recycle it as fertilizer, contributing to sustainable waste management.

Fertilizers Made from Wastes: Industrial waste materials, including hazardous wastes, are sometimes used in fertilizers as a source of micronutrients. EPA encourages the beneficial reuse and recycling of industrial wastes, with standards in place to regulate heavy metal levels in fertilizers.

Concerns and Regulations: There are concerns about the ecological and human health risks associated with certain waste-derived fertilizers. EPA standards specify limits on heavy metals and toxic compounds in fertilizers containing hazardous waste. Some states may have more stringent regulations than federal standards.

Solid Waste Disposal for Agricultural Producers: Agricultural producers can dispose of solid, non-hazardous agricultural wastes on their property, including manure, crop residues, and materials in irrigation return flows, unless prohibited by state or local laws.

This comprehensive understanding of fertilizers, waste recycling, and environmental regulations underscores the importance of sustainable agricultural practices for the well-being of both ecosystems and human health.

Agriculture Nutrient Management and Fertilizer | US EPA (2024)