For Immediate Release: 12-7-2021
For more information contact:
Keri Navratil
712-732-8000
navratil@stormlake.org
In an August 2021 installment of Water Wisdom entitled Wastewater Treatment 101, the basics of turning household wastewater into clear, disinfected water for discharge to the environment were discussed. The wastewater treatment processes that result in clear, disinfected effluent water for discharge also result in the accumulation of biosolids. These biosolids are the residual solids that have been separated from the wastewater, treated with additional processes to reduce pathogens, and dewatered.
The finished biosolids are ready for removal from the wastewater treatment plant and application to local agricultural fields. Land application of sewage sludge (biosolids) is regulated by the Environmental Protection Agency (EPA) and the required standards for application can be found in 40 CFR Part 503. This regulation ensures that biosolids are used or disposed of in a way that protects both human health and the environment by setting general requirements, pollutant limits, operational standards, and management practices for biosolids that are placed on a surface disposal site fired in an incinerator, or land applied.
In 2021, the City of Storm Lake Wastewater Treatment Plant applied 153 dry metric tons of biosolids to local farm fields. According to the EPA, approximately 36% of sewage sludge biosolids produced in the United States are applied in this beneficial manner. Prior to application, the biosolids are sampled for a variety of constituents such as copper, nickel, zinc, and several other metals. Total solids, total volatile solids, phosphorus, potassium, and other parameters are measured as well. The mass of biosolids applied to the land is determined and the mass of each sampled constituent applied is also calculated for record-keeping and determination of cumulative loading. 503 rules set application ceiling concentration and cumulative loading rate limits. Application of biosolids can be accomplished in the spring prior to planting and in the fall after harvest. The biosolids provide fertilizing value, organic content, and serve as a beneficial soil amendment for crops. For additional information on the land application of biosolids please refer to: www.epa.gov.
More tips regarding voluntary water conservations measures and tips for reducing water consumption will follow each Tuesday. Ensuring wise use of our water resources is in the best interest of the community.
Being Storm Lake Proud is not one day, one week, one month, or one event. Being Storm Lake Proud is a magnificent lifestyle! More information about the City of Storm Lake can be found on the city’s website at www.stormlake.org.