April 10, 2012
To the Editor:
Caroline Snyder’s letter to the editor of March 26 was a gross misrepresentation of the facts about the land application of biosolids. While Snyder often presents herself as a scientist by listing her previous association with the Rochester Institute of Technology, it must be noted that she taught in the College of Liberal Arts and not in the colleges of Science, Technology, Engineering or Health Sciences. Her undergraduate and graduate degrees are in Germanic Languages and Literature. She has done no peer-reviewed research in any scientific field—certainly not in biosolids.
The residents of Clarke County can rest assured, however, that thousands of real scientists have been studying the land application of biosolids for many decades and have concluded that it is safe and beneficial to farms and forests. This research and years of practical experience have yet to document any link between biosolids and adverse effects on human health, the environment or to wildlife and domestic animals. New research is continually adding to our knowledge about biosolids and leading to improvements in technology and processes.
Before going further, perhaps a definition of biosolids, based on information provided by the Virginia Department of Health, would be helpful:
Biosolids are the nutrient-rich organic materials resulting from the additional treatment of sewage sludge in a municipal wastewater treatment plant. During treatment, beneficial bacteria and other tiny organisms break the sludge down into simpler, harmless organic matter. The organic matter, combined with bacterial cell masses, settle out to form biosolids, which can then be safely recycled as a fertilizer and soil conditioner.
In 2007, the Virginia Department of Health published a study by three respected epidemiologists that represented an exhaustive review of the current scientific literature about biosolids and human health. The primary conclusions were as follows: “… there does not seem to be strong evidence of serious health risks when biosolids are managed and monitored appropriately. Human health allegations associated with biosolids usually lack evidence of biological absorption, medically determined human health effects, and/or do not meet the biological plausibility test.”
In 2008 an Expert Panel created by the Virginia General Assembly concluded after 18 months of study that it had “uncovered no evidence or literature verifying a causal link between biosolids and illness.”
Snyder completely misrepresented the findings of the National Academy of Science panel on biosolids, which in 2002 issued its recommendations on ways to improve the scientific research supporting the land application of biosolids. Snyder made the false claim that the NAS had said that the EPA’s Part 503 rules, which are the basis for Virginia’s regulation of biosolids, were “flawed,” “outdated science,” and “no science at all.”
Virginia’s biosolids regulations are administered by the Virginia Department of Environmental Quality (DEQ), which Snyder mistakenly called the DEP.
In the preface to its report, the National Academy of Science panel made it clear that its purpose was not to determine the adequacy of the Part 503 rule. Rather, its purpose was to focus “on identifying how current risk-assessment practices and knowledge regarding chemicals and pathogens in biosolids can be used to update and strengthen the scientific basis and credibility of EPA’s biosolids regulations.”
Dr. Thomas Burke, Chair of the NAS panel, issued a statement amplifying the panel’s findings. “First,” he said, “we found no evidence of an urgent public health risk from exposure to land-applied biosolids, based on our review of the scientific literature. Currently, there are no studies documenting adverse health effects from land application of biosolids, even though land application has been practiced for years.”
Finally, it seems highly presumptuous for Snyder, from a distance of more than 650 miles in New Hampshire, to criticize Virginia’s regulation of biosolids. Virginia has recently completed an exhaustive four-year review and revision of the Commonwealth’s biosolids regulations. These regulations, as administered by the DEQ, are among the most comprehensive in the nation and are based on the latest scientific research and practical experience. Virginia’s regulations are more stringent than the federal Part 503 rule on land application rates, slope restrictions, buffers, soil pH and nutrient management plan requirements. These regulations have demonstrated that they are fully protective of public health and the environment.
The DEQ’s Biosolids Program includes 25 full-time personnel who monitor the land application of biosolids in Virginia. According to DEQ records, 93 percent of farms that received biosolids in 2010 were inspected by DEQ personnel.
In my 40 years in the water and wastewater treatment profession I have found that most people, when they have an opportunity to consider the facts, conclude that the beneficial use of biosolids is a win/win for everyone—for the farmers who apply biosolids to their land, for their neighbors who want to preserve the rural nature of their communities, for the environment, for public safety, and for the citizens of the municipalities that use this method of responsibly recycling a valuable resource.
I hope the facts presented here have been helpful to the citizens of Clarke County in understanding the safety of biosolids land application and its many benefits.
Barry Dunkley, P.E.
President, Virginia Biosolids Council
Barry Dunkley is Director of Water & Wastewater Treatment for the City of Danville, Virginia. He is currently the president of The Virginia Biosolids Council, which includes municipal wastewater treatment facilities that produce biosolids, companies that produce compost, companies that apply biosolids to farms and forests and the landowners who benefit from this nutrient-rich soil conditioner. The organization’s website is www.virginiabiosolids.com.