Dioxin Source Revealed

To: Gascape Publications

From: Richard F. Sowinski

RE: As per your request

New Evidence Supports Missing Source of Dioxins and Furans

Following is a summary of our recent findings relating to such an undisclosed and undocumented source of PCDD/Fs entering the environment.

The June 1994 issue of Environmental Science and Technology, page 1797:

"Global deposition of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans is roughly four times greater than annual emissions. More data are needed on emission factors and on introduction rates of PCDD/F to the global atmosphere."

1981 San Francisco Chronicle, August 21 Front Page, news reports continue thru November.

Gas Pipe Rupture Spews PCB Oil - Area Evacuated as reported and is the first public disclosure of PCBs contaminating natural gas pipes.

1986 California voters pass The Safe Water and Toxic Enforcement Act of 1986, commonly referred to as Proposition 65, which requires the Governor to publish a list of chemicals "known to the State to cause cancer, birth defect, or reproductive harm. No warning of PCBs in natural gas is mentioned.

1991 California gas utilities under threat of a suit filed by Natural Resource Defense Council start issuing PROP 65 public warning: Natural gas is contaminated by chemicals known to cause cancer, birth defects and reproductive harm.

1991 Southern Indiana Gas & Electric (SIGECO) Sued by EPA for $14 million for delivery of PCBs into customer's homes. Court documents reveal SIGECO routinely monitors for PCB levels within their gas system, as early as the 1960's.

1992 U.S. Patent 5,145,494 issued September 8

Background Of The Invention

The danger of polychlorinated biphenyls (PCB's) is well documented. PCBs were used as insulating fluids for processing equipment until banned in 1979. Believed to cause cancer, liver and skin damage, sterility and brain damage, the compound has a surprising longevity and once within a human's body, does not dissipate and builds a significant body burden as a function of frequency and level of exposure. Gas utility companies introduced PCB's in gas pipe networks to clean out particulates such as rust, dust, moisture or other gas-laden impurities. Gas line compressor stations also used PCB contaminated oil until banned by Congress. While the EPA and various State Agencies are aware of the problem of PCB's in gas lines, they do not think the exposure danger is of sufficient levels, do not monitor PCB's concentration adjacent to a customer's home, business or like and moreover, do not know how to expunge PCB's from the gas line network since the PCB-contained oil is scrub resistent. In such situation, I find that surprisingly large PCB concentrations sporadically occur. Sources of such a concentration: dampening effects of the compressor-driven network, multiple customer outlet usage, and maintenance practices that add to aperiodic loading of the natural gas stream coupled with surprising longevity of the in situ PCB's. As a result, PCB's can flow to appliances in the customer's home, business or the like at sufficient levels to be a health hazard, and exceed "Federal and/or State health and safety standards. Moreover, since the original source of the PCB's is in the liquid phase, both gas phase and liquid phases (say attached in aerosol form to gas born particulates) are combinable and form the final end-use contamination levels at the appliance to be used.

1995 University of Pennsylvania Research Reported

First manufactured commercially in 1929, due to their unique chemical and thermal stability, Polychlorinated Biphenyls (PCBs) quickly gained widespread use in a number of industries, including gas and electric. Their use continued for more than four decades before their toxic nature was established. Although their production was banned by the U.S. Congress by the Toxic Substance Control Act (TSCA) of 1976, because of their inherent thermal and chemical stability, they persist in the environment. It has been established that, due to past use of PCB-based oil as lubricants in compressors in thousands of gas compressor stations across the country, PCBs entered the natural gas transmission and distribution systems.

What are PCBs?

PCBs refer to a group of aromatic compounds and there are 209 distinct PCB congeners, depending on the number and position of chlorine atoms on the biphenyl. Another subdivision of PCBs is in terms of their degree of chlorination where each group is referred to as a homologue; there are ten homologues of PCBs. The PCB compounds used are known by the trade name of Aroclor in the U.S. and each of these is a mixture of several homologues. Their characterization is therefore very complex; this and their other physico-chemical characteristics makes migration and transport of PCBs very complicated.

What is the problem?

Thousands of miles of gas pipelines are deemed to be contaminated by PCBs. These components may enter the environment through spills and leaks around gas pipelines and compressor stations. In spite of the cessation of use of this product, PCBs have persisted in the pipeline systems, thus necessitating a remediation plan. This plan must be based on a comprehensive understanding of the mechanisms governing the transport and distribution of PCBs in gas pipeline systems. This should be in the form of a predictive computer simulator, since sampling of the entire pipeline system would be cost prohibitive and impractical.

What is the solution?

It must be emphasized that in gas pipelines, PCBs are being transported in the presence of gas condensates, a multiphase dynamic environment. This makes their migration characterization very challenging. Under the sponsorship of Gas Research Institute, Adewumi and his students and associates are currently studying the migration characteristics of PCBs in gas pipelines using multiphase hydrodynamic approach. The understanding gained from this effort will help devise remediation and preventive strategies that would ensure that these toxic substances do not end up in homes and factories. Research efforts in this area target the development of a predictive model that the gas industry would use in devising operational as well as remediation strategies that would help to resolve this problem.

Some Current Research Results

The current research efforts on this front consist of two main areas, namely phase behavior and hydrodynamics. The focus of the research so far in 1995 is developing PCB clean-up scenarios for natural gas pipelines. One method of clean-up that has been investigated is injecting a solvent into the pipeline to remove the PCB from the pipeline. Several solvents were selected and tested with the computer models. Some of these results are presented below.

This graph shows the phase behavior of a natural gas system contaminated with 1 ppm PCB and with 100 gal/MMSCF of acetone injected into the system. The quality lines show the concentrations of PCB in the liquid phase. (Since PCB exists predominantly in the liquid phase, we consider only PCB concentration in the liquid phase.) The dashed red box represents the "operating region" for a typical pipeline, or in other words, the temperatures and pressures that might be found in a natural gas transmission pipeline.

We are interested in the relative shift in the quality lines effected by the solvent. If we can achieve a shift to the right in the quality lines by adding solvent, then the PCB becomes more concentrated in the liquid. Hence, if the liquid is removed from the pipeline, then more PCB will be also be removed. As you can see from this graph, the quality lines do not shift significantly with a fairly high quantity of acetone added. Next, we will see the effect of another solvent, terpinolene, on the phase behavior of the PCB-natural gas system.

In this graph, one can clearly see that there is a dramatic shift in the quality lines within the operating region. By running the phase behavior model for various solvent injection scenarios, we can determine which solvents would hold more potential for clean-up purposes. Hence, in this part of the research, the phase behavior model serves as a screening tool. Our findings indicate that terpinolene would be the best solvent to test in an actual pipeline.

The hydrodynamic model was used to determine the effect of solvent injection on PCB concentration within a natural gas transmission pipeline. A 12,000-foot pipeline segment was tested with several injection rates of terpinolene. The following results confirm that terpinolene effectively reduces the PCB concentration in the liquid within the pipeline.

The hydrodynamic model was modified to account for the PCB adsorption/desorption to the pipe wall. The final step is to run the modified hydrodynamic model in order to determine how long it will take to clean the pipeline. The initial PCB distribution in the pipeline was determined from the previous runs of the hydrodynamic model. The graph shown below indicates that at a terpinolene injection rate of 50 gal/MMSCF, the pipeline is effectively cleaned after 4-1/2 hours. The blue curve shows the initial PCB concentration distribution.

What's Next?

The next step in this research project is to go to the field to conduct some tests. Field testing will allow us to validate and tune the multiphase hydrodynamic model. After the model has been validated and appropriately tuned, clean-up protocols can be recommended. We are optimistic that problem of PCB-contaminated natural gas pipelines will soon be resolved.

Go to Dr. Adewumi's Faculty Page. Go to Penn State's PNGE Home Page. Go to Penn State's Home Page.

The questions we find intriguing from the above effort - is the use of a "flushing agent."

Why would one attempt to flush the gas mains - while ignoring the consumers pipes and appliances?

The next question, known to one trained in the art: Because PCBs are such a persistant chemical, known to stubbornly adhere to any surface it contacts. To completely remove such persistant PCBs from the gas distribution system - would mean replacing the pipes - not cosmetically flushing them out with another chemical additive.

In our opinion, placing a gas filter between the consumer and the supplier would solve the PCB contaminated gas problem.

1996 A new book:

Our Stolen Future

by Theo Colborn, Dianne Dumanoski and John Peterson Myers Are we threatening our fertility, intelligence and survival? A scientific detective story.

1996 Summary of Findings

The natural gas industry has over 1.5 million miles of underground gas pipes containing undisclosed amounts of PCBs. Our research shows this undocumented resivour of PCBs in the nation's gas pipes has been known to the natural gas industry for years.

PCBs residing in said gas pipes, is transported from the gas pipe system into the consumer's gas appliance. Wherein, said PCBs contaminating the gas, enter the appliance flame.

Consumer gas appliances are not designed to incinerate PCBs or any other hazwaste. Thus incomplete combustion occurs at such low consumer gas appliance temperatures - coupled with short residence times for the PCB toxicant. Where incomplete combustion of any PCBs - produces unburned hydrocarbons (UBHs) byproducts such as Dioxins and Furans.

Herein we report, an undiscovered source of Dioxins and Furans, to wit:

"Global deposition of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans is roughly four times greater than annual emissions. More data are needed on emission factors and on introduction rates of PCDD/F to the global atmosphere."

Our findings indicate that natural gas distribution systems contain, an as yet, undisclosed and undiscovered source of Dioxins and Furans which others may be searching for.

Respectfully submitted this sixth day of August, 1996, by

Richard F. Sowinski, D.C.


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