What is sludge? 

Picture everything that gets flushed or rinsed down the drain in your home. In America, we don’t separate our household and industrial waste so all the human waste, cleaners, poisons, soaps, and pharmaceutical combine with the waste of every business, industry, school and hospital to create a toxic stew that collects at one of over 16,000 waste water treatment plants (WWTP). Include in this mix the leachates from landfills, Superfund sites, and other industrial clean-up projects. This is sewage.

The role of the WWTP is to separate the sewage solids from the liquids after treating with chemicals, minerals, squeezing and heating in order to release the water back into our communities. The solid by-product remaining after the water is removed from the sewage is called sludge. Sludge is tested for arsenic, cadmium, copper, lead, mercury, molybdenum, nickel, selenium, and zinc – the nine elements that the EPA requires for testing to determine if it is “safe” to apply to the land that supplies our food and the source of our water. Half of the 7 million tons of sewage sludge created annually in America is land applied.

Where does the sludge go?

Since ocean dumping was stopped in the United States by environmental groups in the 1980’s, because of the dead zones the sludge created in our oceans, disposal options most often used in America include landfill, incineration, and “land application”. What is “land application”? Because of measurable amounts of elements like nitrogen and phosphorous, the sludge industry and government bodies overlook the toxins in sludge and market the sewage by-product as fertilizer. Class A sludge is spread in our parks, golf courses, playgrounds, and forests and sold to the gardening public as bagged fertilizer. The amount of sludge that is land applied varies from state to state depending on how strict the laws are.

Why should you care?

Class A sludge is marketed, and delivered free of charge, to thousands of farmers in 26 states as a fertilizer option. Food crops may be grown in fields treated with Class A sludge without testing the products for levels of pathogens, heavy metals, or pharmaceuticals in spite of the fact that plants uptake nutrients and toxins from the soil. Some of the largest impacts on your health are the personal choices you make about the food you eat, the water you drink, and the community you live in. Meat and dairy animals may graze in fields treated with Class A sludge without testing the product in spite of the fact that heavy metals, hormone mimickers and chemicals collect in muscle and fat tissue.

The issue remains that no substantial scientific studies have ever been done on the hazards or safety of sludge on human health to prove that it is safe!

Lower Susquehanna Riverkeeper believes sludging is a poor choice for communities and our watersheds and works for better science and law to regulate this toxic industry.