Special Report: Sewage Sludge - Valuable Biosolid or Toxic Hazard?

IN THE UNITED STATES: Landspreading Rules Under Investigation

by Doris Cellarius, California Sierra Club

Since the US Environmental Protection Agency (EPA) approved land spreading of sewage sludge in 1993, the neighbours of sludge sites, concerned citizens, environmental groups, and scientists have protested the weaknesses of this program and the harm resulting from it.

Recent reports from both the EPA Office of Inspector General and the National Institute of Occupational Health and Safety have reinforced their concerns. A major congressional hearing in March 2000 featured testimony that public health and the environment are not adequately protected. The National Academy of Sciences was then asked to review the science behind EPA's biosolids standards and how the relevant chemical pollutants were identified.

A great deal of information is now available to assist concerned citizens comment on the need for stringent regulation of sewage sludge.

The Case for Caution

In The Case for Caution, scientists at Cornell University documented the problems with EPA's "biosolids rules":

  • Self-enforcement of the regulations,
  • Lack of permitting processes,
  • Lack of requirements for labelling of products made from sludge,
  • Damage to organisms in soil such as nitrogen-fixing bacteria,
  • The need for stringent standards to prevent leaching of sludge-borne contaminants into groundwater,
  • The need for environmental monitoring for all the possible contaminants (including the ones not yet regulated),
  • Disregard for the hazards of mercury, which EPA wrongly assumed did not volatilize from land application,
  • No monitoring required for viruses,
  • Bacteria can actually increase in numbers during the sewage treatment processes

* Ellen Z. Harrison, Murray B. McBride, and David R. Bouldin: The Case for Caution: Recommendations for Land Application of Sewage Sludges and an Appraisal of the US EPA's Part 503 Sludge Rules, August 1997, updated February 1999. 40 pp. www.cfe.cornell.edu/wmi/sludge.html

The March 2000 EPA Office of Inspector General's audit report, Biosolids Management and Enforcement, concluded that without mechanisms to enforce compliance, "EPA cannot assure the public that current land application practices are protective of human health and the environment."

Worker Health
The National Institute for Occupational Safety and Health (NIOSH) Health Hazard Evaluation investigated worker complaints, interviewed workers, and tested air and waste samples. They concluded, "The detection of enteric bacteria in a limited number of air and bulk samples confirms the potential for workers to be exposed to organisms which have been associated with gastrointestinal symptoms and illness."

NIOSH recommended additional practices to prevent the risk of disease among workers who are exposed on the job to biosolids used to fertilize agricultural lands or mine reclamation sites.

Metals and Toxics
Many people do not realize that for land applications of sewage sludge, the United States has the most relaxed standards for metals among developed nations. Currently EPA regulates only nine metals: arsenic, cadmium, copper, lead, mercury, molybdenum, nickel, selenium, zinc; and the standards for what is allowed are up to 100 times higher (weaker) than any other country has ever proposed. The problem with synthetic organic chemicals such as PCBs and pesticides such as lindane, is even worse.

The Environmental Working Group analyzed the only available national data on sludge content, the 1988 National Sewage Sludge Survey of 208 treatment plants. Their report Dumping Sewage Sludge On Organic Farms? Why USDA Should Just Say No, reported "a total of over 100 synthetic organic compounds (not including pesticides) in US sludge, including phthalates, toluene, and chlorobenzene." Dioxins were found in sludge from 179 out of 208 systems (80%). In addition, 42 different pesticides were found, at least one in almost every sample. None of these chemical contaminants are regulated in sludge. The nine heavy metals that are regulated were routinely detected, often at high concentrations. No comprehensive data are available to assess if these toxic components of sludge have been reduced since the late 1980s.

Toxic Waste In Fertilizers

Waste Lands: The Threat of Toxic Fertilizer, released in May by US PIRG and the State Public Interest Research Groups, reported that American fertilizers are contaminated with toxic metals. Twenty-nine fertilizers, purchased in twelve states were tested by Frontier Geosciences, and found to contain arsenic, lead, mercury, cadmium, chromium, and dioxin. Twenty fertilizers exceeded levels of concern for disposal in landfills.

Fertilizers become contaminated when manufacturers buy toxic waste from industrial facilities to obtain low cost plant nutrients, such as zinc or iron. Such industrial wastes are often highly contaminated with persistent toxic chemicals.

http://www.pirg.org/toxics/ reports/wastelands

Soil at Risk
The US sludge program also appears to be putting long-term soil productivity at risk. Studies in Europe have found that microbial functions in soils are affected at metals levels that are not toxic to crops. Scientists have found heavy metals in earthworms from sludge-treated soils; rodents fed those earthworms accumulated cadmium, copper, lead and zinc.

Compared to the US, there has been more concern and research in European countries about the effects of sewage sludge on soils and ecological processes. An article in Environmental Science and Technology states: "Evidence began to emerge about 10 years ago that sludge-borne metals could have adverse effects on total soil microbial biomass and on nitrogen fixation by cyanobacteria and by the nitrogen-fixing bacteria Rhizobium."

The evidence, which was not conclusive at that time, came from long-term experiments at sites where sludge was repeatedly applied in large quantities. The article describes research showing that other species of nitrogen-fixing bacteria are adversely affected by high zinc concentrations in soil.

Endocrine Disruptors
When EPA's biosolids rules were developed, there was little concern about the problems caused by low-level exposures to the many unregulated chemicals. Nonylphenols are endocrine disrupting chemicals that enter surface waters as degradation products of detergents, shampoos, other cleaning agents and pesticide formulations. Their sublethal effects on fish and other aquatic life are of recent concern.

Nonylphenol-based surfactants have been phased out in Europe, but they are still widely used in the United States. Surfactants are quantitatively the most important synthetic organic compounds in municipal waste water. Surfactants such as linear alkylbenzene sulphonates and nonylphenol polyethoxylates, although partially degraded under aerobic conditions, are lipophilic and not degraded anaerobically. They and their degradation products, such as nonylphenol, become highly enriched in sewage. At present there is neither monitoring nor regulation of nonylphenol concentrations in sludges in the United States.

Phthalates are chemicals added to plastics to make them flexible. Because they are not chemically bonded to the plastic itself, they leach out of IV bags and many kinds of packaging materials. After disposal, they contaminate groundwater. Some phthalates have been identified as carcinogens, teratogens, and endocrine disruptors. Scientists in Puerto Rico recently found elevated levels of phthalates, but no other contaminants, in the blood of young girls diagnosed with premature puberty. Safer alternatives are available.

Dioxin is another contaminant of sewage sludge that was not considered when the EPA's sludge rules were written. A national inventory of dioxin sources, the EPA Dioxin Exposure Initiative, reported that a significant release of dioxin to the environment was from the "land spreading of waste water treatment sludge." This is a great concern because some crops grown on sludge-treated land are fed to animals, cows and other herbivores that ingest soil as they graze. The greatest route of human exposure to dioxin, a human carcinogen, is through consumption of meat and dairy products. In December 1999 EPA proposed a standard for dioxin levels in biosolids, a limit of 300 parts per trillion toxic equivalents for dioxins in biosolids that are recycled and applied to the land as fertilizer.

The environmental and public health community provided testimony calling that number far too high to be protective. EPA has not yet issued a final dioxin limit for sewage sludge.

Activists who believe sewage sludge seriously endangers public health have been sharing information on their web sites and bringing it to government officials. More of us need to inform ourselves and speak out.

* For more information contact doris.cellarius@sierraclub.org


IN BEAUTIFUL BC: Sludge Regs Ready to Roll

BC's Sewage Sludge Regulations, innocently titled Organic Matter Recycling Regulation pose a new danger to the health of British Columbians. The regs have been written, and may or may not be issued shortly, depending on discussions within the new government.

As well as the long overdue composting of farm and fish waste, the regulations set standards for the composting of municipal sewage sludge, and the land spreading of uncomposted "Class B" sludge. As it now stands, Organic Matter Recycling Regulation is problematic, and the problems are predictable:

  • These regulations are based on toxics standards from the 1980s or even earlier.
  • The allowable levels of heavy metals are many times higher than those allowed in Europe.
  • The Regulation does not require testing for any of the industrial chemicals (such as dioxin, PCBs, PAHs and other chemicals recognized federally as toxic) or antibiotics, in modern urban sewage.
  • Uncomposted sludge with up to 2 million fecal coliform per gram can be spread 30 metres from adjacent homes, lakes, streams, and wells.
  • Land which receives sewage sludge is then exempted from Contaminated Sites Regulations!
  • There are no limits to the amount of sludge per hectare, as there are in every sewage sludge regulation from other jurisdictions.
  • The Ministry of Environment is unable to monitor or enforce compliance, according to the provincial Auditor General and the British Columbia Government Employees Union.
  • Once this Regulation is proclaimed, citizens will have no legal recourse to challenge land spreading near their properties.

* The BC Organic Matter Recycling Regulation can be downloaded at:

* During the week of February 11, 2001, CBC Radio presented a series called Troubled Waters. The segment on sewage sludge spreading, "Soiling our Own Nest" is available at: http://radio.cbc.ca/programs/thismorning/sites/health/water_010211/troubledwaters_main.html

* Contact: Jack Bryden, Pollution Prevention and Remediation Branch, BC Ministry of Environment, Lands and Parks, phone: (250)387-9985.

* Sources and Resources

  • United States Environmental Protection Agency 2000, Office of Inspector General, March 20, 2000, Biosolids Management and Enforcement Audit Report. 2000-P10. www.epa.gov/oigearth/audit/list300/00P0010.pdf
  • National Institute for Occupational Safety and Health, Health Hazard Evaluation Regarding Health Risks from Exposure of Workers to Class B Sewage Sludge. July 2000. DHHS (NIOSH) Publication No. 2000-1580.87 www.cdc.gov/niosh/hid10.html
  • Congressional Science Committee Hearing, March 22, 2000. Search for EPA's Sludge Rule: Closed Minds or Open Debate? March 22, 2000 on the page www.house.gov/science/106_hearing.htm#Full_Committee
  • Harrison, Ellen Z., Director, Cornell Waste Management Institute. Testimony before the House of Representatives Committee on Science, March 22, 2000. www.cfe.cornell.edu/wmi/Sludge/testimony.html or www.house.gov/science/harrison_032200.htm
  • Environmental Working Group, Dumping Sewage Sludge On Organic Farms? Why USDA Should Just Say No, April 30, 1998. 1718 Connecticut Ave. NW, Washington, DC 20009. www.ewg.org/pub/home/Reports/SludgeMemo/sludge.html
  • Renner, Rebecca: Sewage Sludge Pros and Cons: The United States and the European nations are far apart on their views of what constitutes safe management, Environmental Science and Technology, October 1, 2000/ Volume 34, Issue 19. Pgs. 430 A – 435 A.
  • Ewing, Richard: Diminishing Returns: Salmon Decline and Pesticides, Oregon Pesticides Education Network. Feb. 1999. www.pond.net/~fish1ifr/salpest.htm
  • Blount, Benjamin C., et al.: Levels of Seven Urinary Phthalate Metabolites in a Human Reference Population, Environmental Health Perspectives, Volume 108, Number 10, October 2000.
  • Pennsylvania Environmental Network: www.envirolink.org/orgs/pen/issues/sludge/index.html

* Published with the assistance of the Friends of Cortes Island Watershed Sentinel Fund


IN ONTARIO: A Guide to Action on Sewage Sludge

by Maureen Reilly

The sludge comes from a waste water treatment plant, which filters sewage until the water is clean enough to return to a river or lake. The remaining 'sludge' is what is deemed 'biosolids.' Biosolids is just a nice new name for sewage sludge.

The treatment plant has a Certificate of Approval (CoA) from the Ontario Ministry of Environment (MoE) that sets out standards the plant must meet, such as how many days the sludge has to stay in the digester.

Some municipalities put their sludge in a landfill, some incinerate, some land apply. The municipality pays a hauler approximately $100 per dry tonne to haul the sludge away to put on farm fields.

The hauler must apply to the MoE for a CoA, a legally binding document which sets out how the sludge is to be spread. It is called a "Provisional Certificate of Approval to Operate a Waste Management System" (but there is nothing 'provisional' about it). Once the hauler has this CoA, they can start signing up farms to spread.

Each farm site then needs a CoA as an 'Organic Waste Disposal Site,' which states which fields will be spread, and must indicate all water courses, wells, slopes, residences, etc. There must be a signature from the landowner (not just a tenant farmer or cash cropper) permitting sludge to be applied.

If you request a CoA for a site, be sure to ask for the Operating CoA as well as the site CoA. These are public documents. Often the MoE will fax them, or mail them, or you can go to the office and pick up a copy.

Unless it is specified in the CoA, there is no requirement to notify neighbours, and no right of appeal.

Some Certificates require that sludge entering a township or county from a different community must have a motion of concurrence from council that the municipality has 'no objection' to the sludge spreading. The municipality can also set out conditions that then become part of the Certificate of Approval and are enforceable by the MoE. For instance, a municipality can require that sludge be incorporated into the soil, or that they receive notification of all sites, or that each site must observe the Guidelines for the Use of Biosolids in all of its recommended provisions.

The municipality can pass by-laws to manage sludge – zoning, hours of operation, road use, odour and noise, etc.

Biosolids Guidlelines:
http://www.ene.gov.on.ca/envision/gp/3425e.pdf These Guidelines set out recommendations and requirements for sludge spreading. There are many more recommendations than requirements. The Guidelines are only enforceable if written into a CoA.

Biosolids Utilization
Committee: http://res2.agr.ca/initiatives/manurenet/en/buc.html This is a group of 22 people, including industry representatives, who provide advice to the ministries of environment and agriculture. The Committee has been in place for more than 20 years under one name or another.

Health Unit Local Medical Officer of Health:
The Health Unit has an obligation to respond to health complaints. The Health Act requires it. Note all health concerns or complaints to the Health Unit. Preferably in writing.

If the spreaders are violating their Certificate of Approval, you can call the police. Or call Crime Stoppers. Or the Spills Action Centre.


Charges in Ontario

In June, the Ontario Ministry of Environment laid 14 charges against PowerGrow, a sludge disposal site. The charges, based on practices from May 1999 to June 2000, include putting sewage sludge and paper sludge on 'organic soil Conditioning Sites' in excess of 164 tonnes per hectare and putting the sludge on sites without a Certificate of Approval. As well, the company is cited for compost that failed to achieve the temperatures required for pathogen reduction.



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