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Dear Maureen,
I don't have anything quite so specific. However, there are several reports/studies detailing dioxin output from burning TDF as well as burning hog fuel.
At a 5:95 ratio of TDF to hog fuel, the effects of TDF would be expected to be relatively unnoticeable in a hog fuel boiler that is burning wood that is salt-laden, treated with pentachlorophenol, etc. But this is not to say that there is no dioxin problem. Under carefully controlled conditions, the increased dioxin output should be evident in a hog fuel boiler that is burning clean wood. Excerpts of some of the studies addressing hog fuel boilers are shown below:
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Pandompatam, B., Kumar,Y., Guo, I., Liem, A.J. Comparison of PCDD and PCDF emissions from hog fuel boilers and hospital waste incinerators. Chemosphere 34:[5-7]:1065-1073. 1997.
"A pilot-scale incinerator with a nominal capacity of 50 kg/h was successfully used to simulate PCDD and PCDF emissions from hog fuel boilers processing NaCl contaminated bark. With 0.76 wt. % chlorine in the bark, about 50 and 100 ng/m3 of total PCDD, total PCDF were detected. The corresponding PCDD and PCDF values for the uncontaminated control bark were 0.3 and 0.3 ng/m3. The Toxicity Equivalent (TEQ) for the 0.76 wt. % salt contaminated bark combustion was 3 ng/m3 as compared to the control value of 0.02 ng/m3."
"In the pulp and paper industry, "hogged fuel," consisting of saw dust and bark is usually burnt for energy recovery purposes.
Recent field studies [ 2,3,4] showed that PCDD and PCDF are formed from combustion of sodium chloride (NaCl) contaminated hog fuel. The salt contamination occurs during the sea transportation of logs to the coastal pulp mills. The concentration of salt in the hog fuel can vary up to 1% dry weight while the typical moisture level is approximately 50%."
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U.S. Environmental Protection Agency, "Estimating Exposure to Dioxin-Like Compounds: Volume II: Properties, Sources, Occurrence and Background Exposures," EPA/600/6-88/005Cb, U.S. Environmental Protection Agency: Washington, DC, June 1994
"3.6.12 Tire Combustion
... an average emission factor of CDD/CDF was estimated to be 1.39E- 02 ug/kg of tires incinerated ... and average emission factor of TEQ was estimated to be 5.42E-04 ug/kg ...
...
Buser et al (1991) indicated that PCDTs (polychlorinated dibenzothiophenes, possibly a dioxin-like compounds) can be formed where large amounts of sulfur and chlorine-containing compounds are incinerated or accidentally burned. Automobile tires are known to contain sulfurous ( vulcanization) compounds and certain types of chloro compounds (e.g., chloroprene). Thus, it is possible that the burning of used automobile tires could result in the formation of PCDTs."
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You might also want to take a look at the Canadian Dioxin Inventory, which can be downloaded from their website. Hog fuel burners are identified as dioxin sources both to air and to water (via disposal of the boiler ash)
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Environment Canada and the Federal/Provincial Task Force on Dioxins and Furans, 1999. Dioxins and Furans and Hexachlorobenzene
Inventory of releases, January 1999
Before the adoption of the Pulp and PaperRegulations in 1992, the PCDDs/PCDFs released from this sector in liquid effluents amounted to approximately 450 g TEQ/year. The last status report for this sector indicates that the total release from the sector is now 5 g TEQ/y. Individual plants monitor their effluent as per the regulations and report the data to the government.
The PCDDs/PCDFs releases for the Pulp and Paper sector are based on an inventory of the 1995 discharges. The high contribution from British Columbia mills is due to the character of the effluents from the coastal mills.
These show the presence of higher concentrations of certain homologues. The congener pattern of these are linked to the operations of boilers that burn salty hog, where waste ash is disposed in the effluent treatment plant. Also there are indications of a pattern associated with pulping of chips from wood treated with pentachlorophenol .
These activities were not associated with either Inland British Columbia mills or mills elsewhere. The unique circumstances of the coastal mills explains why the British Columbia discharges are greater than the production from these mills would account for.
Canada Total: In Ash from Boilers 137.2 [g TEQ/yr] Burning Salt Laden Wood (P&P)
Canada Total: Atmospheric Releases 10.5 [g TEQ/yr] from Boilers Burning Salt Laden Wood
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There is ample documention to refute the premise of allegedly "safe" landfills. For example, look at the next to last sentence of the abstract of this recent paper:
Westlake, K. 1997. SUSTAINABLE LANDFILL - POSSIBILITY OR PIPE- DREAM? Waste Management and Research 15: 453-461
"Too often a sustainable landfill is described in terms of operational technique (e.g. bioreactor landfill or repository for pretreated waste) rather than the more appropriate goal of managing a landfill such that the environmental risk is acceptable. The technique that achieves the lowest risk landfill will vary according to a number of factors including the waste composition, climate and local geology/hydrogeology, and will vary from country to country, region to region, and site to site. A truly sustainable landfill is one in which the waste materials are safely assimilated into the surrounding environment, whether or not they have been treated by biological, thermal or other processes, and which manages gas-related problems so as to minimize the environmental impact. This is more likely to be achieved in containment landfills, but recognizing that liner failure will occur ultimately, and that in the long term, the escape of waste materials and their products of degradation is inevitable. Appropriate site selection, design and management is crucial to the attainment of more sustainable waste management.
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Pat Costner
Greenpeace
P.O. Box 548
or 512 County Road 2663
Eureka Springs, Arkansas 72632
ph: 1 501 253 8440
fx: 1 501 253 5540
em: pat.costner@dialb.greenpeace.org
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