Friday, August 8, 2008
Some claim health risks associated with sludge application
Biosolids applied to the land for the purpose of enriching the soil is being touted as free fertilizer for farmers.
But some question the real cost – the long range implications of land application of sewage sludge – or biosolids.
The practice of trucking sewage sludge from municipal and city sewage treatment plants to apply onto farm fields has been going on for years. Land applications are generally made in the spring, fall, and after the wheat crop is harvested.
But, at least one eastern Will County resident, Dale Waldvogel, whose family raises animals on their Will Township farm, is concerned about the practice fearing that it is a hazard to the soil, environment, and ultimately, human health.
Waldvogel watches each year, first noticing what he describes as a “horrible smell.” Then there is the seemingly never-ending convoy of heavy trucks filled with the stuff that traverse the country roads that aren’t designed to accommodate them. But he has greater fears than those mere annoyances. He fears the safety of the practice of land application.
Waldvogel is not alone.
There are questions about the land application practice, not only in Will County, but in small rural towns across the country, as well as in Canada, Australia, Europe, and other parts of the world.
Biosolids are the solid waste by-product from municipal sewage treatment – the result of everything flushed down toilets and poured down drains. Solid waste managers claim the dried, treated sludge is safe enough to put on the strawberry patch. But is it really?
The Sierra Club and others don’t think so. While the Sierra Club is not opposed to the use of pathogen-free, pollutant-free treated waste used as fertilizer, they stipulate that to be safe, there must be a separation of human waste from industrial waste.
They classify urban sludges as “highly complex, unpredictable biologically active mixture of organic material and human pathogens, some of which are resistant to antibiotics or cannot be destroyed through composting sludge.
“It can contain thousands of industrial chemicals, including dozens of carcinogens, hormone disrupting chemicals, toxic metals, dioxins, radionuclides and other persistent bioaccumulative poisons.”
According to the Sierra Club, the Federal Clean Water Act defines sewage sludge as a pollutant and banned the practice of dumping it into the ocean in 1989.
Land application was the answer to the question of what to do with an estimated 10 to 15 million dry metric tons of sewage sludge produced each year.
In 1993, the U.S. EPA issued its land application rule for the Use and Disposal of Sewage Sludges, (40 CFR, Part 503). The new law gave sludge a bit of a makeover.
To enhance its acceptability for land application, the agency began to call it “recycling.” And if it met the newly-created EPA standards, the new term for the sludge became “biosolids”.
With the new terminology came a new classification. As recycled biosolids rather than simple sewage sludge, it was no longer considered a pollutant, which exempted it from the most stringent laws governing waste disposal.
One of the reports upon which Sierra Club based its opinion and written policy, was the 2002 National Research Council of the National Academy of Sciences. The report warned that sewage sludge standards needed a new scientific basis.
“The agency (EPA) should update its standards using improved methods for assessing health risks,” the council stated, adding that the agency should also further study whether treated sewage sludge causes health problems for workers who apply it to land and for residents who live nearby.”
The Sierra Club charges that the regulatory standards for biosolids includes only nine metals, making the U.S. land application regulations the least protective of any in the industrialized world.
In Canada for instance, land application of biosolids is permitted, according to one Ontario chapter of the Sierra Club. It added that in the U.S., the application of biosolids is actually endorsed by the EPA.
According to the Cornell Waste Management Institute 2007 study for applying sludge to farm fields, developed by nine scientists from five universities, “No sewage biosolids management method is risk free.” They advocate working to establish guidelines for the most stringent requirements, but acknowledge that the practice carries with it “a certain degree of risk that is not fully knowable or quantified.”
The study states, “The benefits of amending soils with sewage biosolids are well documented primarily linked to the fact that sewage biosolids return nutrients and organic matter to the soil. However, management practices for sewage biosolids must include an awareness of potential adverse impact on soil, animal and human health. The presence of trace elements, synthetic organic chemicals and disease-causing organisms (pathogens) places constraints on the management of sewage biosolids by land application.”
According to the Toronto Star which did a series of stories about the risks to human health and the environment by using sludge biosolids, there are other ways to treat the mounds of waste being flushed into toilets and poured into drains.
It pointed out that Europe is discontinuing land application practices in an effort to preserve its agricultural soil. Instead they are utilizing non-polluting technology to convert sewage sludge from contaminated waste to a renewable resource to create biogas, heat, power, and energy.
Alternate disposal of waste is also being eyed in New Zealand where the sludge is being used in anaerobic ponds to harvest algae which is then converted into biofuel.
The treated liquid, after clarification could then be used for truck and car washing, as an ingredient in ready-mix concrete and as non-potable water for use in washing machines, toilets, and garden hoses.
New concerns about sludge application resulted from a ruling in March of this year, by a federal judge in Augusta, Georgia who ruled in favor of a farmer – Andy McElmurray – who sued the U.S. Department of Agriculture over poisoned land. McElmurray claimed the sewage-based fertilizer poisoned his land and killed his cows by the hundreds.
U.S. District Judge Anthony Alaimo awarded the farmer compensation for the 1,730 acres of poisoned ground on which McElmurray had planned to grow corn and cotton.
The sludge that was used on McElmurray’s land was reported to “contain levels of arsenic, toxic heavy metals and PCBs two to 2,5000 times the federal health standard.”
In a 45-page ruling Alaimo said, “The EPA not only used questionable data to examine the health risk on McElmurray’s farm, but that EPA officials took extraordinary steps to quash scientific dissent questioning of EPA’s biosolids program.”
Judge Alaimo wrote that data endorsed by Agriculture and EPA officials about toxic heavy metals found in the free sludge provided by Augusta’s sewage treatment plant was ‘unreliable and incomplete, and in some cases fudged.’”
The City of Augusta, where the sludge originated recently settled a lawsuit with McElmurray for $1.5 million for the dead cows. A nearby dairy farmer, Bill Boyce also won a $550,000 court judgment against the city on a similar claim that sludge was responsible for the deaths of more than 300 of his cows.