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Soil Amendments – What they are and proposed legislation

In Georgia, soil amendments are defined as additives that alter the physical properties of the soil, i.e. soil texture. These can be used to reduce erosion, improve water retention, change soil pH, enhance nutrient holding, and/or re-establish microbial communities. All vital for soil remediation and revitalization. Soil Amendments do not enhance nutrient value of soil. They are not fertilizer.

Unfortunately, due to incomplete and unenforced regulations, the Georgia Dept of Agriculture Soil Amendment program is being abused to enable quasi-legal to straight-up illegal dumping of untreated industrial waste streams including waste from slaughterhouses, fat-traps, wood-ash, and humans.

The science is clear that utilizing properly treated and properly applied soil amendments  are beneficial for changing physical properties of soil. The science is also clear that without proper treatment and regulation, industrial by-product (IBP) and wastewater treatment plant (WWTP) sludge can harm the land and the citizens of Georgia. IBPs include material from industries (like restaurants, kitchen, food processing, and slaughterhouses) that is derived from living matter. WWTP sludge is semi-solid material recovered from sewage.

Untreated and improperly treated IBPs and WWTP Sludge contains toxic pathogens such as Salmonella, bacteria, viruses, and prions (mad cow disease), and heavy metals, all of which are a human health risk. They may contain high loads of antibiotics which can lead to increased antibiotic resistance in humans and livestock. An emerging worry is PFAS concentrations, which are not remediated by current treatment techniques.

The Georgia Department of Agriculture already regulates soil amendments. All amendments must be licensed and labeled. IBP amendments must also provide information about industry of origin, production process, and suitable application rates. WWTP Sludge amendments must also be Class A sewage sludge and contain information on facility(ies) of origin and suitable application rates.

These regulations are a good start to protecting our land and our health. Strengthening enforcement of regulations and transparency of reporting is needed to ensure that soil amendments are:

  • Utilized by farms for agriculture purposes
  • Safe for humans and the environment

To ensure the above, it is key that the contents, location, and amount of all soil amendment spreads be known to maintain transparency for farmers and the larger community.

Gross Stuff Being Dumped
Here is a Quote from a news article – Zach Mitcham. “Ag practice or waste disposal? Madison Co company sued over spreading practices in Oglethorpe, Wilkes counties.” Madison Journal Today, Dec 24, 2020.
A report from a Jan. 3, 2020 inspection by Jennifer Wren of the Georgia Department of Agriculture included photographs of the [property in Lexington, GA]. Wren was there with two representatives from the Georgia Environmental Protection Division.
She wrote that “piles of whitish material near the storage pond were visible from the road.”
“A strong odor seemed to emanate from the piles of whitish material, and red liquid pooled around the edges of the material,” wrote Wren. “Shortly after our arrival, a tanker truck (labeled as Leon Jones Feed & Grain, Inc.) delivered a load to the site.”
Wren said Smith told her the material she observed at the property was a “registered lime product from IsoNova, although he could not provide any kind of label or documentation.”
“I verified that IsoNova Technologies LLC (formerly known as American Dehydrated Foods, Inc.) does hold a current lime license with the Department (license # 36) with one registered product: A.D.F. Egg Shells,” wrote Wren. “Upon closer inspection of the material, there appeared to be feet, heads, and other body parts of very young chickens incorporated with the shells and feathers.”
About an hour later, a second load was delivered to the site by Leon Jones Feed & Grain, Inc., Trucking.
“The material delivered in this load was noticeably pinker in color than the other piles of eggshell mixture,” she wrote.
“A closer view shows the ‘pink’ colored objects to be chicken carcasses, which appeared to comprise most of the load,” wrote Wren. “Mr. Smith explained that he plans to spread this material on the surrounding fields as a liming agent and then plow it in, but he has had to wait on clear weather to do so.”
She wrote that Smith told her he “receives this material approximately five days a week, with around two to three loads on each of those five days.”
Wren wrote that “the composition of the loads is highly variable, with some piles appearing uniform and finely ground, while other mixtures were more heterogeneous.”
Wren and a fellow Department of Ag inspector returned to the Smith property on Jan. 7 “to determine if the eggshell material had been incorporated into the soil over the weekend” and found “no apparent changes to the stored material, although flocks of carrion birds could be seen feeding on the piles.” Smith was told “he must dispose of the carcasses in one of the permitted ways by Wednesday, January 15, 2020.”
Wren visited IsoNova’s Dahlonega site and met with plant manager Daniel Rice, who said the site is a “liquid effluent retention facility (LERF) that “receives hatchery waste/offal from 28 Georgia hatcheries.”
Current State of Georgia Regulations
The Georgia Department of Agriculture currently issues licenses for soil amendments. According to current code, soil amendments must:

1.       Include a label with the following
o   The product name;
o   A statement of product benefit;
o   The concentration of active and inert ingredients;
o   Recommended directions for use;
o   The net weight or volume; and
o   The name and address of the registrant.

2.       If the amendment is derived from in industrial by-product (i.e. produced by a restaurant, kitchen, slaughterhouse, or food processing facility or from an industrial by-product which contains animal, fruit, or vegetable matter, liquid or otherwise) supplemental information must be provided:
o   The information is covered by Rule 40-31-2, Provisions Applicable to Industrial By-Product Derived Soil Amendments.
o   Information about the industry that produces the by-product
o   Contents of the amendment and process by which it is produced
o   Intended use of amendment and suitable rates / frequency of application to a site
o   Additionally, 40-31-3.02(h) 1 & 2 specify:
§  “NMPs will specify that IBD soil amendments with greater than or equal to 85% moisture content be applied via subsurface injection.”
§  “NMPs will specify that IBD soil amendments with less than 85% moisture content be applied by topical application followed by incorporation into the soil within 6 hours of application.”
o   A representative analysis must be conducted.

3.       If the amendment is derived from sewage sludge (biosolids) only, “Class A Sewage Sludge” can be used and supplemental information must be provided:
o   facility(ies) that the sludge came from
o   Intended use of amendment and suitable rates / frequency of application to a site
o   A representative analysis must be conducted.
By listing the contents of the amendment, the source of the amendment, and the intended use – farmers can ensure that they are applying something useful to their land, and their neighbors can feel confident they are not being exposed to anything harmful.
Given that IBP and WWTP derived amendments can contain a host of ingredients that are harmful to human and environmental health, a recommended addition to the current regulation would be testing for and listing of concentrations of processing chemicals, PFAS, heavy metals, and toxins.
The Dangers of Untreated IBP and WWTP Sludge
Slaughterhouse IBPs are highly unstable and ripe for unhygienic conditions. The high water content and the high fat content combine to produce waste that can contain microbes and pathogens that can spiral out of control. 
Untreated Slaughterhouse waste typically contains an abundance of nutrients, possible pathogens, and of antibiotics. Nutrient abundant run off from land application of untreated waste into streams and rivers causes algae blooms, temperature changes, and oxygen depletion, all of which harm the existing aquatic life. Pathogens include Salmonella, which are a human health risk. And high loads of antibiotics can lead to increased antibiotic resistance in humans and livestock. 
WWTP sludge “contains toxic and less toxic pollutants, organic matter, pathogenic microorganisms, inorganic substances, and heavy metals (cadmium, chromium, copper, lead, mercury, nickel, zinc, platinum and platinum group metals (PGMs), silver, etc.)” – From “General considerations on sludge disposal, industrial and municipal sludge” Anna Grobelak, et al.
Human exposure to excess amounts of heavy metals has been shown to have various detrimental effects on different body systems including gastrointestinal, kidney, immune system, and nervous system disorders, skin problems, circulatory damage, birth defects, and cancer. When exposed to more than one heavy metal toxin, there are cumulative effects, increasing the damage.
Potential Contaminants in Sludge
Untreated IBP-derived soil amendments may include contaminants which can pose a risk to both human and environmental health. These possible contaminants should be considered when suggesting testing protocols and requirements.
·         Salmonella
·         Botulism, tetanus
·         Brucellosis
·         Anthrax
·         M. Bovis (Beef Tuberculosis)
·         Erysipelothrix rhusiopathiae
·         BSE (mad cow)
·         Foot-and-mouth
Heavy Metals
·         Cadmium
·         Chromium
·         Copper
·         Lead
·         Mercury
·         Nickel
·         Zinc
·         Platinum and platinum group metals (PGMs)
·         Silver
Proper Treatment to Produce a Beneficial Soil Amendment
Slaughterhouse IBPs used to be disposed of as animal feed or other food by-products. But the risk of pathogens and prion diseases (mad cow) have limited the profitability as feedstock usage. Instead, non-food uses are becoming more popular. Studies have shown that Anaerobic Digestion combined with pasteurization is an effective method to properly process IBPs. It creates two things. 1) Biogas + Methane and 2) nutrient rich digestate. These are mutually beneficial, as the methane can be used to pasteurize the digestate, which can then become bedding for livestock, flower pots, soil amendments, and fertilizers.

Proper disposal of the biosolids from WWTPs is done via landfilling, incineration, or land application. Landfilling is inexpensive, but to prevent environmental exposure, it must occur into properly maintained and lined landfills. Landfilled waste emits methane, a potent greenhouse gas. Incineration reduces the volume of waste via burning, but also produces CO2. The incinerated ash then goes to a landfill or can become construction material. Incineration is expensive and requires appropriate scrubbing to prevent the release of harmful air pollution. Land application of biosolids can restore soil health and are a slow-release form of nutrients, both of which are economically valuable to farmers and reduce harmful nutrient runoff. It must be properly treated to remove pathogens and heavy metals. In this case, Anaerobic Digestion combined with pasteurization is a viable treatment alternative.
Emerging PFAS Concerns
An emerging concern for all types of waste is PFAS concentration. PFASs have been linked to a host of human health problems including obesity, liver disease, blood pressure problems, and cancer.
PFAS concentration in an individual application will vary greatly depending on the source. Current treatment strategies employed at WWTPs and IBP treatment plants (anaerobic digestion and composting) are ineffective.
“Without appropriate mitigation methods, human exposure could occur from wastewater through de facto and planned potable reuse, or through bioaccumulation into food or leaching into groundwater from biosolid application sites.”  – From Thompson, et al.
To reduce PFAS overall, they should be phased out of new products, and remediation technologies should be implemented in WWTP and IBP treatment plants. In the meantime, to reduce the spread of PFAS back into the environment, soil amendments should be tested for PFAS concentration and permits should be issued only for those with an acceptable level of PFAS. Landfill disposal of the rest is environmentally unsustainable, but an unfortunate necessity until remediation treatment technology is utilized.
Benefits of Properly Treated Soil Amendments
Soil amendments are a key part of a circular economy where waste is utilized to improve soil health and reduce environmental impacts.
“The addition of amendments restores soil quality by balancing pH, adding organic matter, increasing water holding capacity, re-establishing microbial communities, and alleviating compaction. As such, the use of soil amendments enables site remediation, revegetation and revitalization, and reuse” – EPA
It is important to note that in researching this memo, peer-reviewed research discussed how to treat IBPs and WWTP Sludge so that it could be used. No study looked at spreading untreated material due to the overwhelming negative effects that have been outlined herein. It would be ethically unviable.
Policy Examples
Illinois, New Mexico, and Hawaii have policies that define the characteristics of a beneficial soil amendment. Generally, these policies aim to restore or otherwise improve the soil’s rates of erosion, water retention, maintenance of its root systems, organic matter, and ultimately care for the “health, yield, and profitability of soils throughout the state.”
The State of Minnesota requires that an IBP be tested for:
·         Chloride
·         Nitrogen, Ammonia
·         Nitrogen, Kjeldahl
·         pH, Sludge
·         Phosphorus
·         Sodium
·         Solids, Total
·         Solids, Total Volatile
·         Oil and grease, Total Recoverable
·         And any pollutants that have a reasonable likelihood of being present – based on where the IBP came from.

What can I do about it?

Contact your Georgia General Assembly Legislator about this issue. HB 1223 is now before the General Assembly and begins to address this issue.

Learn how to be respectful and direct to your legislator here.

Download this fact sheet and send it to your legislator.

Download this whitepaper to share.

Learn More

Soil in Georgia ~ Georgia Soil and Water Conservation Commission

Learn about composting

Learn about PFAS

Learn about CAFOs

What is in Chicken Litter

Learn how a farm can diversify their land management techniques

Learn about soil health and land management

Learn about soil amendments and soil productivity

Soil Amendment Terms and Definitions

Soil Amendment 

Any product or substance added to the soil, via active tillage into the soil, with the purpose of enhancing the soil to make it better suited for growing. Key components are

  1. The amendment is tilled into the soil and/or injected below the surface to ensure absorption and prevent runoff.
  2. The amendment enhances the physical properties of soil itself by restoring pH levels, changing water holding capacity, and/or adding material that restores overall soil health.  
  3. An amendment is not “fertilizer” which does not change the soil itself. Fertilizers are for plant use only and do nothing to the soil itself. Soil amendments make the land more able to sustain plant life. 

Industrial By-Product

Any material that originates from industry (food processing, slaughterhouse, restaurant) that consists of material derived from living matter (animals or plants). 

Wastewater Treatment Plant (WWTP) Sludge

A watery mixture of solids that is left over after wastewater is treated and the clean water released back into the environment.


An industry term referring to WWTP Sludge that has been treated and able to be applied safely to the land.

Organic Materials

While “organic” is often used to imply a specific set of farming and production practices. In this case, organic refers to any material derived from living organisms (plants or animals).

Fats, Oils, and Greases (FOGs)

FOGs should not go to landfills or sewer systems as they can cause clogs and other problems. Instead, FOGS should be processed via 3 pathways:

  1. Rendering – turn into animal food, cosmetics, soap, etc. Many companies provide free pickup for this type of waste.
  2. Biodiesel.
  3. Anaerobic Digestion.

Anerobic Digestion (AD)

AD is one method of treating organic materials that come from IBP or WWTP sludge. The material is placed in an oxygen free environment and microorganisms break it down to produce

  1. Biogas (methane and carbon dioxide → which can become natural gas)
  2. Digestate – this end-product is nutrient rich. It has a solid and liquid component. When properly treated it can become:
    Bedding for livestock
    Soil amendments


Sterilization of a product, often through heating to high temperatures, to make it safe for use.

Per- and polyfluoroalkyl substances (PFAS)

Per- and polyfluoroalkyl substances (PFAS) are class of chemicals used since the 1950’s to make products resistant to heat, oil, stains, grease, and water. PFAS are widely used as coatings are on a variety of products, including furniture, food packaging, and electrical wire insulation.

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