The April 23 Washington Post article about the Blue Plains Sewage Treatment Plant Upgrade contains a number of false claims about the nature and safety of Class A sewage sludge/biosolids. Class A contains robust pathogens that have not been killed by the new process and which can regrow in cool and moist climates. It also contains an array of toxic metals and synthetic chemicals that are neither regulated nor monitored, including some that are highly toxic and can harm organisms in very small doses.
Every month, every industry, institution, and business in the Washington DC area is permitted to discharge 33 pounds of hazardous waste into Blue Plains. As these industrial pollutants are removed from the waste water, they concentrate in the resulting biosolids. To compare sludge with toothpaste and claim it is safe to put in your mouth is irresponsible. There is no similarity between pre-industrial night soil and modern sewage sludge. Field studies indicate that sludge pollutants can be absorbed by plants and get into milk of dairy cows that graze on sludged pastures.
There is nothing “forward looking” or “green” about spreading industrial waste on farms or in gardens. This unwise practice has been going on for decades, even though the latest National Academies of Sciences report confirmed that there is no credible science to support the practice. Soil scientists and hundreds of farm, health, and environmental groups, including the Sierra Club, oppose using biosolids as a fertilizer.
This contaminated waste can be utilized in a safer and more sustainable way as a domestic, non-fossil source of renewable energy. The technology to so exists and is being used in several European countries.
For more information about the serious risks linked to using sludge and sludge products as fertilizer, visit www.sludgefacts.org
Caroline Snyder is emeritus professor at the Rochester Institute of Technology, Rochester NY, where she designed, administered, and taught environmental science courses. She founded and chairs Citizens for Sludge-Free Land.
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