Are you a farmer? Do you own a farm? Do you have direct or even direct contact with biosolids land application? Are you running a property that uses biosolids to fertilize its soil? Most probably, the biosolids that you are purchasing are being produced by treatment plants located in your municipality or the municipalities near your area. The transit of biosolids is a big challenge for treatment plants, so the access of the general public to biosolids is limited to where the treatment plants are located.
Before using biosolids on your own land, make sure to ask the wastewater treatment facilities for the following information: the required buffers around streams and wells, the metal and nutrient content of the biosolids, the results of soil testing, the calculations for the correct agronomic rate, the amount of biosolids to be applied on a specific portion of land, and the record of how much biosolids were applied on each field.
Pay particular attention to the data on metal and nutrient content of the biosolids because this could directly affect your farm. Part 503 of the regulations of the US Environmental Protection Agency defined specific levels of pollutants such as arsenic, cadmium, copper, lead, mercury, nickel, selenium, and zinc that would be harmful or would not pose health risks. As a farmer who use biosolids, you should have this chart explaining the levels which are acceptable and unacceptable for land application.
The level of metal in the biosolids you are going to apply on your land should be below the monthly average concentration on the chart provided by the EPA. If it’s over the level indicated on the chart, it means that the metal concentration level in the biosolids could pose health risks.
The obligation to ensure the safety of biosolids land application does not only fall on the wastewater treatment facilities. As a farmer, you should also make sure that the pH level of your soil will remain above 6.5 and below 7.0 to 7.5 because this would keep the metals in the biosolids bound only to soil particles.
The treatment plant should also provide for you information on the nutrient content of biosolids. Remember that there is such a thing as over-application of nutrients on land. The data from the plant should have information on the amount of nutrients that will be supplied by the biosolids and the amount of biosolids that your land can take. The right amount of nutrients such as nitrogen, phosphorus, and potassium must be applied to ensure crop growth.