The use of biosolids has been the subject of much debate over the past year mainly because of the many benefits it poses to the environment and to the agricultural land. However, there are still a lot of people who are skeptical about it because of where it comes from.
Biosolids is an organic matter sourced from treated wastewater sludge. Domestic waste goes through a treatment process that does not completely kill and eliminate the pathogens on the liquid matter in the waste. This liquid matter will be further treated in facilities to separate the liquid from the solids. Once the process was completed, the solids would be an organic matter called the biosolids. This is the reason why wastewater sludge is not biosolids and vice versa.
Although many people make the mistake of interchanging these two terms, sludge is still the “dirty” component of non-treated biosolids while biosolids can already be applied on agricultural land, forestlands, and home gardens.
What is Class A biosolids
Biosolids are classified by the US EPA into three categories: Class A, Class A EQ, and Class B. Class A is the designation given to dewatered and heated sewage sludge that meets the US EPA guidelines for land application with no restrictions. This means that you can apply Class A biosolids on farms, vegetable gardens, and home gardens. It is safe to use on and near food-producing soil. And yes, you can eat produce from soil that has been fertilized or amended by biosolids.
According to the EPA guidelines, Class A biosolids must “contain no detectable levels of pathogens.” The elimination of pathogens from Class A biosolids is important because this is where contaminants and pollutants can be detected. When pathogens enter the soil and consumed by people, this will pose great health risk and hazard.
The pathogens measured and regulated under the law are fecal coliform and salmonella, which are usually passed through food and water. This is a problem because there are other contaminants that could enter the stream. Some of the contaminants that have been found on biosolids, even Class A biosolids, are anions, metals, semi-volatile organics, polycyclic aromatic hydrocarbons, steroids, hormones, and flame retardants, among others.
However, as long as Class A biosolids contain no salmonella and fecal coliform, it should be safe for use in the production of crops and vegetation. In the long run, the benefits of being a cheaper alternative to commercial fertilizers with the nutrient it pack are enough reason to consider biosolids for agricultural land application.