8.1	Toxic Releases from Power Plants

Along with the emission of acid rain/smog causing pollutants, the utility sector is also responsible for the release of toxic metals including arsenic, cadmium, hexavalent chromium, lead, mercury and nickel.

As of 1998, electric power plants burning coal or oil must estimate and report their annual releases of toxic substances listed in the US Toxics Release Inventory (TRI). The TRI is a comprehensive public database of annual emissions to air, water and land of over 600 chemicals and chemical categories designated as toxic by the USEPA. Any facility within a listed industry sector is required to report to TRI if it has the equivalent of 10 or more full-time employees and 'manufacturers' or 'processes' more than 25,000 lbs of any listed chemical during the reporting year or 'otherwise uses' more than 10,000 lbs per year of any listed chemical. For mercury and other chemicals that never will be produced in greater amounts than the reportable threshold noted above, the USEPA has proposed lowering the reporting threshold to 10 lbs/yr beginning in the year 2000. At this proposed value, mercury would become reportable for most coal-fired plants. The primary focus of the reporting is on coal-fired power plants, which are the dominant source of US power generation, accounting for roughly 50 per cent of electricity production.

The newly listed facilities are given a year following the report year to submit their TRI emissions to the EPA. There is usually a one year lag period before the EPA makes the emissions inventory available to the public.

Any of the 17 metals in Table 15 below, that are 'manufactured' in amounts totaling more than 25000 lbs/yr are reportable. However, affected sources are not required to conduct any new measurement programs for purposes of TRI reporting; rather a facility can estimate its reportable emissions using currently available information.

Most US power plants do not measure emissions of trace substances, and many coal-fired plants lack data on the trace substance content of the coals they burn. To estimate the TRI releases in the absence of site-specific data, a computer model has been developed, called the PISCES model. It employs a fundamental mass balance approach to account for multimedia flows of chemical substances in fossil fuel power plants. The PISCES Model is used to identify and quantify reportable TRI chemical releases for a representative coal-fired power plant design, determined to be a 650 MW facility, burning an average 1995 bituminous coal (28380 kJ/kg, 1.5 per cent

sulphur, 9.8 per cent ash, 6.7 per cent moisture) operating in compliance with the Phase I acid rain emissions cap. This plant size was selected to approximate the average size of US coal-fired facilities, whose sizes span a large range (see Figure 9).

The trace element concentrations in coal were taken as median values for all bituminous coal used for power generation, as reflected by approximately 200 coal samples in the PISCES database.

The PISCES study determined that the reportable releases for the representative plant included seven of the 17 metals in the previous table, plus hydrochloric acid, hydrogen fluoride and sulphuric acid aerosols. The dominant emissions are HCl (hydrochloric acid) and H ₂ SO ₄ (sulphuric acid); HCl accounts for 56 per cent and H ₂ SO ₄ for 24 per cent of the total mass of emissions. Overall, air releases amount for 85 per cent of the total plant release inventory; land releases are 15 per cent and trace metal air emissions are less than 0.1 per cent of the total. Total toxic releases for this average plant exceed 4 million pounds per year.

The case study was intended to provide representative estimates of power plant TRI releases. However, the nature and quantity of such releases will vary significantly across the population of US coal-fired plants. A number of factors affecting reportable releases include:

• Plant size and operation : The size of a given facility is a key determinant of annual chemical discharges. Chemical releases would scale in proportion to plant size, if all other factors are held constant. Larger plants or higher capacity values also can cause additional chemical species to exceed the TRI threshold and become reportable.
• Fuel Properties : Variations in coal composition across the US can have a marked impact on the number of reportable TRI chemicals and the magnitude of TRI releases.

• Plant Configuration : The specific configuration of a power plant can have a marked effect on the magnitude of chemical releases to different environmental media.

The table below summarizes the magnitude of combustion-related releases for the case study facility.

• Plant Operating Practices : Plant operating practices can influence the types and quantities of TRI chemicals that are otherwise used since utilities may have a choice of chemicals employed for water treatment and plant maintenance activities that contribute to TRI releases.

The analysis suggests that the dominant chemical emissions from most coal-fired power plants in the US will exceed the reporting thresholds for the Toxics Release Inventory (25,000 lbs/year). Some oil-fired facilities also may have reportable emissions.

Emissions from the electric utility sector will substantially alter the national picture of toxic releases currently portrayed by the TRI. For comparison, the total 1996 release for the US chemical industry was 785 million lbs and, for the metals industry, 564 million lbs. These have been the two top industry groups on the TRI in the recent years. The total estimated utility release of over one billion pounds/year substantially exceeds either of these industries and could be as large as the two combined. Similarly, the top three TRI chemicals in the past have been methanol, zinc compounds and ammonia. The estimated power plant releases of HCl alone is 2 to 4 times their values.

The magnitude and prominence of power plant toxic releases will place increasing pressure on the electric utility industry and EPA to explain and interpret TRI results. Electric utilities will likely cite a recent EPA study of hazardous air pollutants which found that risks from power plant emissions of HCl, mercury and other TRI substances were typically well below the level of concern. At the same time, EPA can be expected to emphasize that TRI data are intended to be evaluated in the context of site specific and community-level situations and that designations such as 'nonhazardous' do not necessarily imply the absence of site -specific risks or toxicological effects on environmental organisms. In the longer term, the TRI also is likely to stimulate efforts to better quantify power plant releases and to reduce toxic emissions consistent with the pollution prevention objectives of TRI and the industry capability to respond.

The Binational Toxics Strategy was signed by Canada and the US in 1997. It is a strategy to virtually eliminate Level 1 and Level 2 persistent toxic substances, some 40 in all, including mercury, in the Great Lakes and the surrounding areas.

US Mercury Challenge and Progress:

• to achieve a 50 per cent reduction in mercury use nationwide by 2006, and a 50 per cent reduction in the aggregate of US air emissions; nationwide and releases to water in the Great Lakes [emphasis added]
• Use: 21 per cent reduction achieved from 1995-1997 levels
• Release: 28 per cent reduction from 1990-1995 levels

Canadian Mercury Challenge and Progress:

• to achieve a 90 per cent reduction in the release of mercury, or where warranted, the use of mercury in the Great Lakes Basin , by 2000 [emphasis added]
• Release: 73 per cent reduction from 1988 levels

The New England Governors/Eastern Canadian Premiers Mercury Action Plan (1998), has set an overall regional objective of reducing mercury emissions by at least 50 per cent, by year 2003. These reductions will be carried out through emission reductions as well as source reductions.

The Mercury Reduction Plan recommends the following:

8.2.2.1

Coal Boiler Mercury Control Technology Options and Targets

The Mercury and Acid Rain Workgroups, established under the Conference, has focused on fulfilling the commitments concerning utility boilers and related mercury and acid gas emissions adopted by the Conference of New England Governors and Eastern Canadian Premiers on October 5, 1999. Their study of control options and reduction targets for electrical utilities recognized the need for a multi-pollutant control strategy.

In further development of a 'Mercury Action Plan,' the Joint Coal Boiler Workgroup, drawing on members from the Acid Rain Steering Committee and the Mercury Task Force , proposed action on the following objectives consistent with a multi-pollutant approach.

• Complete a cross cutting investigation of new technologies to reduce mercury, sulphur dioxide (SO ₂ ), and nitrogen oxide (NO _X ) emissions from coal-burning boilers.

• Encourage further studies to assess technical and economic characteristics

• Recommend control options and targets.

The Workgroup believed that the economic feasibility of controlling mercury emissions from coal-fired boilers could be evaluated by estimating the costs, both capital and operating, of emerging and available controlling technologies, and pricing these on the basis of an increase in cost (in cents) per kWh of electricity to the residential consumer.

Based on estimates in the March 1999 EPA report 'Analysis of Emissions Reductions Options for the Electric Power Industry', a 70 per cent reduction of current utility mercury emissions in the US is expected to cost approximately $1.7 - 1.9 billion per year (or about $20,000/lb mercury reduced). The estimated equivalent cost to consumers would be an increase of 0.2 - 0.3 cents per kWh (or about a 2 - 3 per cent increase on the consumers monthly bill). These estimated costs are largely similar to those associated with NO _X removal from boilers in the part of the US subject to the revised NOx SIP Call.

While the estimated cost for mercury reduction can be assigned to the reduction of mercury alone, in reality, current control technologies can also reduce other pollutants simultaneously. For example, wet scrubbing reduces mercury emissions, and has the potential to also eliminate a significant portion of sulphur dioxide and particulate emissions. Along with control technologies, conversion of coal-fired boilers to natural gas fuel would reduce emissions of SO ₂ , NO _X , and mercury substantially. Thus, the technologies for mercury control must be evaluated for their cost effectiveness in ameliorating the entire utility emissions stream.

Deregulation and Standards

The targets and goals suggested by the Joint Coal Boiler Workgroup take into account the expected joint benefits (multi-pollutant reduction) of potential control technologies. The need to establish a common cost calculation method for this multi-pollutant approach is also emphasized in the report to the Governors and Premiers.

Currently, most Northeast states have taken steps to restructure the utility industry and introduce competition in electricity generation. Deregulation was expected to provide significant economic benefits for industry and perhaps consumers; however, if not appropriately bounded, it could lead to a noticeable increase in the negative environmental impact of the electricity industry.

In order to address this concern, state and local regulatory agencies are establishing a variety of laws and regulations, including Emission Performance Standards (EPSs) and information disclosure. An Emission Performance Standard requires that the average emission rates of the electricity created and marketed be at or below a specific EPS level for each pollutant. Failure to comply with the EPS could lead to withdrawal of the supplier's license to sell electricity within a given region.

Information disclosure procedures have been developed by some states to educate consumers about the environmental consequences of their electricity purchase decisions, and allow for 'comparison shopping.' Typically, suppliers are to indicate their supply fuel characteristics and emission rates to consumers, including a comparison of the latter to the emissions performance benchmarks.

When combined, EPSs and information disclosure could encourage the purchase of electricity from cleaner, more efficient generating facilities. However, effective implementation of these provisions would require the establishment of verified information systems linking suppliers' power supply characteristics to specific electricity generating facilities.

i) Recommendation to Offset Emissions of 'New' Mercury

'New' mercury is mercury released from below the earth's surface as a result of natural and industrial processes. While many of these actions described above, if implemented, would curtail 'new' mercury emissions, even after the best controls, some residual emissions of 'new' mercury may occur.

To minimize the addition of mercury to the global pool, it is recommended that the post-control emissions of mercury from all coal-burning electric power generators be required to be offset by a reduction of an equal or greater amount from the existing global pool, as long as emissions from the generator continue. To ensure permanent removal, a national repository for the safe storage of mercury so recovered is recommended.

ii) Emissions Reduction Timelines and Targets

The Joint Coal Boiler Workgroup is developing proposed emission targets and timelines for mercury, sulphur dioxide, and oxides of nitrogen from coal-burning electrical facilities for consideration by the Conference. The targets are preliminary and are regional goals, rather than jurisdictional or point source measures.

At the moment, the workgroup is considering total mercury reductions from coal-fired utilities of approximately 70-90 per cent from 1995 levels by approximately the year 2010, accompanied by simultaneous reductions of NO _X * and SO ₂ of 50 per cent within the same timeframe, through the implementation of the NEG/ECP Acid Rain Plan and the Canada-wide Standards.

Regulations to achieve these reductions should be based on performance standards and emission rate limits, not percentage reductions.

New control standards for mercury, and NOx are also under consideration by the Group for coal-fired industrial/commercial/institutional (ICI) boilers with a rating greater or equal to 250 mmBTU per hour gross heat input.

*Note: The input to output conversion factor found in the USEPA's New Source Performance Standard for both utility and industrial units, is 0.15 lb NO _X /mm BTU heat input, approximately equivalent to an 1.6 lb NO _X /MWh gross output.

In North America, coal-fired electric utility boilers represent the largest source of anthropogenic mercury emissions. It is the only source that continues to operate in the absence of a mercury reduction strategy. In an effort to address this issue, in March of 1999, the CEC organized a meeting of air quality professionals in Montreal, Canada. As a result of the meeting, a number of findings and recommendations for action were developed, specific to the reduction of mercury

from coal-fired electric generation plants. An edited selection of these is reproduced here, along with the table (Table 17) of some of the CEC technical findings on this issue.

Finding 1 - Data Acquisition and Dissemination

• The quality and quantity of mercury emissions data from coal-fired power plants be improved for the public and policy makers.

It is Recommended That:

• By December 31, 2000, the threshold limit for mercury emissions for inclusion in the pollutant release and transfer registers of the countries in North America be lowered to amounts that: (1) better reflect the level of impact associated with this pollutant, and (2) would result in the reporting of mercury emissions from a majority of coal-fired power plants in each country.
• All load serving entities in North America be required to disclose both their pollutant emissions characteristics, and fuel sources of the power sold to all individual, including residential, retail customers.
• The initial verification of emission factors for mercury from coal-fired utility boilers be completed by no later than June 30 of this year. These factors should be used to determine mercury emissions per unit of energy produced. This value should be benchmarked against a national average of all retail suppliers and reported on consumers' monthly bills.
• Sampling and analyses of the mercury content of coal, as well as emissions stack testing, should be extended to ensure the quality of emissions data.

Finding 2 - Role of Technology-Forcing Performance Standards

• It appears that coal will continue to be a dominant fuel in North American power plants, for some time in the future.

It is Recommended That:

• A national, technology forcing performance standard, to achieve a 90 per cent reduction in mercury from all existing and new coal-fired utility boilers, be proposed on or before December 31, 2003, and final compliance required within 2007 to 2010 time frame. Incidental reductions of mercury resulting from the control of other pollutants should be considered part of the 90 per cent requirement.

• Public funding be made available in sufficient amounts to ensure completion of the needed demonstration projects for the most promising mercury reduction technologies by June 30, 2003.

• The handling and storage of mercury contaminated waste be controlled so as not to allow re-entry into the environment.

Finding 3 - Retail Supply Standard

• Alternative energy sources such as wind, solar, etc., have the capacity to meet a greater portion of the current and future demands for electricity, therefore reducing the resultant pollution emissions.

It is Recommended That:

• Retail supply standards be initiated, which promote maximum use of renewable energy, cleaner technologies and alternative fuels. A retail supply standard would take the form of a mass emission of mercury per unit of electrical power produced.

Finding 4 - Use of Market-Based Strategies

• Appropriate and bounded market-based strategies have the potential to lower the overall level of bio-accumulative, neurotoxic exposure to mercury without increasing individual exposure

It is Recommended That :

• No market-based approaches be employed which create the opportunity for increased individual exposure to mercury.
• Market-based approaches serve to augment traditional regulatory approaches, not replace them.
• In the evaluation of any market-based approach, uncertainties in measurement and environmental impacts be interpreted conservatively.

Finding 5 - Multi-Pollutant Benefits

• Control strategies are developed on a pollutant-by-pollutant basis. As a result, even though a control device could reduce the emissions of several pollutants, it is viewed in a single pollutant context. This inflates the cost by assigning the full cost of the emission control strategy to the targeted pollutant, while ignoring the environmental benefits realized in the control of other pollutants.

It is Recommended That :

• Mercury emission control strategies should continue to focus on maximizing mercury emission reductions. However, in evaluating a given control strategy, its benefit and/or cost effectiveness should be considered within the context of the whole emissions stream, including SO ₂ , NO _X , PM and carbon dioxide.

8.2.4

Canada-wide Standard for Mercury

Once a mercury molecule is in the atmosphere, it can circle the globe several times before returning to earth, and entering the streams, lakes, forests and fields. Mercury levels in most wildlife and fish have not declined over the last ten years, notwithstanding the reduction in anthropogenic mercury emissions. This is largely due to the continuing cycling of anthropogenic and natural emissions around the globe.

The mercury levels in wildlife and fish in most parts of Canada are at a level that consumption is cautioned by the government. This deprives some communities, particularly First Nations, of a substantial portion of their traditional diet.

Canada maintains that a large part of the threat comes from the mercury emitted by other countries in North America and around the world reaching Canada by atmospheric transport.

Therefore, while controlling Canadian emissions will reduce the overall burden, it alone will not eliminate the problem.

In developing the Canada-wide standards for mercury, the Ministers noted that three sectors contribute significantly to the total anthropogenic mercury emissions of 12 tonnes/year; the base metal mining sector (2.8 T/y), waste incineration (1.2 T/yr) and coal-fired electrical generation (1.5 T/yr).

The CCME proceeded to propose standards for two of the three segments; base metal mining and incineration. In the case of the third sector, coal-fired utilities, they indicated that the complexity of the issue would preclude completion of a standard into the latter part of 2000.

Canada's largest industrial source for mercury emissions has always been base metal smelting. Since 1988, Canada's leading smelters have lowered their emissions by 94 per cent, but further reductions will be required.

For new and expanded facilities , the proposed emission guideline is .2 g mercury per tonne of finished zinc, nickel and lead, and 1 g/tonne of finished copper, as well as a consideration of a mercury offset in which a new facility will recover and retire an amount of mercury equivalent to its annual emissions to ensure no 'net' emissions increases. The guideline for existing facilities is set at 2 grams of mercury per tonne of total production of finished metals. All facilities are expected to make a 'determined effort' to meet the standard by year 2008. Attainment of this standard at current production levels should reduce mercury emissions by 800 kg/yr by that year.

Estimated emissions within the incineration sector include 446 kg/yr from municipal waste incinerators, 250 kg/yr from medical waste incinerators, 550 kg/yr from hazardous waste and 285 kg/yr from sewage sludge incineration facilities. Changes in waste content, treatment technology and processes have reduced the mercury content in incinerator emissions by an estimated 60 per cent since 1990.

For new and expanded facilities , the following standards would apply immediately

Sewage Sludge incinerators, 70 µg/Rm ³ at 11 per cent O ₂

Individual jurisdictions will determine what constitutes an expansion sufficient for application of the standard.

For existing facilities , the stack gas concentrations would, in some cases, be determined by the capacity of the facility. All municipal waste incinerators would be required to meet the 20 µg/Rm ³ standard, while medical waste incinerators with capacities above 120 tonnes per year would fall under the 20 µg/Rm ³ standard; those facilities processing less than 120 tonnes per year

would have a 40 µg/Rm ³ standard applied to them. Both municipal and medical waste facilities are to endeavor to meet the standards by the year 2006.

Existing hazardous waste incinerators and sewage sludge incinerators would be required to meet a 50 µg/Rm ³ and a 70 µg/Rm ³ ceiling by the year 2003 and 2005 respectively.

Larger facilities are to be subjected to annual stack testing and smaller medical and municipal facilities will have the option of reporting on a successful mercury diversion plan or conducting a one time stack test.

A series of reports will be prepared for the Ministers; in the year 2004 on compliance of one incineration sector and progress on the others, in the year 2007 compliance by all incineration sectors, and an overall compliance result for all appropriate sectors in the year 2010. A single report to the public is then to be prepared.

Each jurisdiction will determine the exact means of ensuring compliance in a manner consistent with the typical or desired programs for the affected facility or sector.

The proposal standard does consider the issue of data reporting, noting that a consolidated data-report and an 'achievement of compliance' report is to be made available to all jurisdictions and the Ministers, along with a draft public report; the latter would be released to the public upon approval by the Ministers. The suggested form of the public report would demonstrate progress based on an aggregate of data to the provincial level; although jurisdictions must provide a contact to the public for facility specific information, such data are to be supplied in a manner consistent with the normal data and compliance reporting procedures of the jurisdiction in question. The consolidated spreadsheet is not be made public as it may include propriety information.

The proposed CWS limits for mercury in incineration exhaust gases are compared to other relevant standards in Table 18.

Recommendation

The Commission should recommend to the Canadian Council of Ministers of the Environment that data on mercury emissions from individual facilities be made available to the public through the CCME website and other means. If absolutely necessary, provisions could be made for the exclusion of process (not emissions) details from this information due to confidentiality agreements; the rationale for doing so should be described.

8.3

Benzene

For some time, benzene has been classified as a known human carcinogen. It is also a non-threshold toxin, that is a substance considered to harm health at any level of exposure. The primary management goal for a non-threshold toxin such as benzene is to limit human exposure. Human exposure routes are given in Figure 10.

Transportation emissions and natural gas dehydrators are Canada's leading sources of benzene, accounting for 90 per cent of the nation's total release. Some minor sources include: residential wood/garbage burning, production of gasoline, the steel industry, and chemical manufacturing. The largest source of benzene exposure to Canadians is vehicular emissions, and to cigarette smokers, the exposure levels are even higher.

8.3.1

Canada-wide Standard for Benzene

Canadian Emissions and Regulation

The largest source of benzene emissions into the atmosphere, in both Canada and the US, is from gasoline combustion, as seen in Figure 10. Regulations have been developed under the 'Canadian Environmental Protection Act' (CEPA), and further Canada-wide Standards are being considered to control the level of benzene and other harmful compounds in gasoline. These regulations will reduce the amount of benzene in vehicle exhaust, as well as emissions of benzene throughout the gasoline distribution network particularly pumps at gas serving stations.

Figure 11 suggests that human exposure to benzene is mostly due to cigarette smoke inhalation, rather than automobile exhaust, even thought there are more benzene emissions released from total fuel combustion.

New regulations controlling the amount of benzene in gasoline at 1 per cent by volume, came into effect in Canada in 1999, with the introduction of the "Benzene in Gasoline Regulations." The goal of the regulations, along with the proposed Canada-wide Standard on benzene, is to reduce the releases of benzene from gasoline-fueled vehicles by developing a gasoline which contains lower concentrations of such chemicals as toluene and benzene.

These regulations should reduce emissions/release of benzene from vehicles and service stations significantly. The estimated cost of reducing the benzene content in gasoline (standard) is between 0.2 and 0.4 cents per litre. Once these standards apply fully (estimated to be May 2000), Canada will have one of the most stringent national gasoline standards in the world.

• Phase 1 of the benzene CWS sets a target of 30 per cent reduction in national benzene emissions from 1995 levels, to be achieved by the end of year 2000.

It provides an accountability mechanism for various current actions towards a Canada-wide control strategy and the coordination of monitoring and reporting on these activities, as well as a means of establishing a baseline for future action at no incremental cost. Ambient air concentrations of benzene will be reported as an indicator of air quality, with the first public report by September 30, 2001. Reports on the achievement and maintenance of the standard will follow annually and comprehensive reports are to follow every 5 years, beginning in 2006.

• Phase 2 is to be developed by the spring of 2001 through consultation with stakeholders and will identify the long term direction for benzene control. The target and goal of phase 2 may include an ambient concentration level, a further national reduction target, or a combination of initiatives.

The key actions which will achieve this standard include:

1)	regulation of benzene in gasoline;

2)	voluntary initiatives to reduce emissions from natural gas dehydrators and the chemical industry; and,

3)	reduction measures in the steel industry.

8.3.2

US Emissions and Regulations

Benzene is a widely used chemical in North America, and especially in the US, with only 15 other chemicals being produced at greater volumes. Elimination of exposure to benzene is virtually impossible; however, stringent standards can be set for gasoline concentration and other benzene sources.

The USEPA has completed a study on motor vehicle-related air toxics, which was required under the Clean Air Act Amendments of 1990. The report states that the current average levels of benzene in gasoline in the US are approximately 1.5 per cent by volume, and that the fraction of benzene in exhaust generally runs 3-5 per cent. Through the Clean Air Amendments of 1990, the USEPA has required a reduction in the benzene content of reformulated gasoline, to a limit of 1.0 per cent by volume. A similar regulation is expected for benzene content in gasoline (non-reformulated).

Since benzene can also be produced from engine combustion of other aromatic hydrocarbons present in gasoline, other regulatory approaches such as alternative fuels may also be necessary for further significant benzene emission reduction. The USEPA is considering using several regulatory programs to further limit the amount of benzene in gasoline, one being a simple cap, which would lower the level in gasoline. In addition, the USEPA is offering an emission performance standard similar to that of the RFG (reformulated gasoline) program, in which refiners of all gasoline, instead of just reformulated gasoline, would be forced to reduce emissions of benzene, as well as other toxics.

8.4	Dioxin and Furan Emissions

The term 'dioxin' is commonly used to refer to a family of toxic chemicals that all share a similar chemical structure and a common mechanism of toxic action. Dioxin is widely distributed throughout the environment in low concentrations, and bio-accumulates in the human system; most people have detectable levels of dioxin in their tissue. These levels have accumulated over a lifetime and will persist for years, even if no additional exposure were to occur. Current background exposure is likely to result in an increased risk of cancer and is close to levels suspected of causing subtle adverse non-cancer effects in animals and humans. Over the last two years, the Board has undertaken a modeling of the atmospheric transport and deposition of this substance from sources and source regions across the United States and Canada to the Great Lakes basin.

8.4.1

Uncontrolled Combustion of Refuse: Open Barrel Burning

As part of the deposition study referred to earlier, the Board has overseen the development of an emissions inventory for dioxin that is among the most current available. However, a recent US EPA study concluded that the burning of a barrel of domestic waste could emit the same amount (or more) of dioxin and furan into the atmosphere as a well-controlled municipal waste incinerator serving thousands of residents. Further confirmation of this research and suitable extrapolation, nationwide, may reveal that open refuse small scale burning could be one of the largest sectoral sources of dioxin and furan emissions in the United States and Canada. The IAQAB is currently incorporating a revised estimate of national dioxin emissions from this source category into its database.

The estimated emissions of selected toxic substances, including dioxin, from burn barrels per year are shown in Table 19. An ongoing EPA study to determine the contribution of dioxin and furan pollution from open barrel burning could contribute to the resolution of a long-standing discrepancy between estimates of dioxin emissions and actual deposition measurements.

Household waste can include anything from papers to plastic, metals and organic wastes. Allowing combustion gases and particulate to intermingle at a low temperature, as in barrel burning, provides an ideal atmosphere for dioxin formation. The features of a combustion system which will increase the production of dioxins include:

• poor gas-phase mixing;
• low combustion temperatures;
• oxygen-starved conditions;
• high PM loading;
• PM-bound copper;
• presence of HCl and/or chloride; and,
• significant gas-phase residence time in the 250-700 ^o C temperature range.

In the EPA study, ordinary household waste was incinerated in a 55 gallon drum. The mixture of trash included newspapers, books, magazines, mail, cardboard, milk cartons, organic wastes, plastic, cans, bottles and jars. No paints, grease, oils, tires or other hazardous wastes were burned. The emissions were compared to those of a well-controlled incinerator, meeting EPA dioxin standards. Kilogram for kilogram, the emissions from the open barrel burning were several orders of magnitude higher than the controlled combustion incinerator.

In the United States, the burning of household waste is regulated under the Natural Resources and Environmental Protection Acts. In addition, local units of government such as city, county and township boards, often regulate the burning of household waste. Burning waste in barrels is illegal in most of the US, and many parts of Canada, but some municipalities still allow this practice.

The average person in the US generates 3.72 pounds of solid waste per day and more than 50 million people live in non-metropolitan areas in America. The USEPA estimates that 40 per cent of the people living in non-metropolitan areas burn their waste and 63 per cent of their daily waste is burned in burn barrels. These data suggest that over 1.8 billion pounds of household waste is burned in barrels every year. Backyard burning may add 800 grams of dioxins (as TEQ- TCDD) annually to nationwide emissions, currently estimated to be about 3000 grams TEQ-TCDD from all sources.

Backyard Burn Barrels vs. Properly Controlled Municipal Waste Combustors - Preliminary Estimates

Per Unit of Waste A burn barrel emits 10,000 times more dioxin than a MWC. A burn barrel emits 1000 times more total furans than a MWC. A burn barrel emits 3000 times more polycyclic aromatic hydrocarbons than a MWC.

Backyard burning has other deleterious impacts.

• Chemicals in smoke are unhealthy to inhale, and have caused asthma and other respiratory effects in humans, especially in small children and pregnant women.
• The smoke contains hydrochloric acid and formaldehyde, which are especially irritating to the eyes.
• Materials which contain chlorine can create dioxins when burned at low temperatures.
• Burning inked papers releases heavy metals into the atmosphere, which have been linked to birth defects and cancer.
• Burning polystyrene products releases styrene into the air, which can be readily absorbed into the skin and lungs. At high levels, styrene vapors can damage the eyes and mucous membranes.

Recommendation

The Commission should recommend governments recognize the significant contribution of the backyard open burning of trash to the total burden of dioxin on the Great Lakes system, and ensure that the curtailing of this activity will be integrated into plans and strategies to eliminate loadings of dioxin to the Great Lakes.

8.4.2

Canadian Action

The Canadian federal government has recently lowered reporting requirements for the release of information of their most dangerous and toxic substances. Environment Canada will now require increased disclosure from major industrial polluters of their use of dioxins and furans. Under the new standards, any production of dioxin and furan must be reported, because of the severity of their negative health effects.

Polluting companies will be required to track their micropollutants beginning this year. The information will likely be available late next year or early 2002.

8.5	MTBE (Methyl Tertiary Butyl Ether) Update

The 1990 Amendments of the US Clean Air Act established a number of programs to produce cleaner motor vehicles, and cleaner fuels, which, so far, have been highly successful. One main program is the Reformulated Gasoline (RFG) Program. The RFG requirements emerged from combining several Congressional objectives, including air quality improvement, the use of oxygenates (such as MTBE) to improve fuel combustion and lower emissions of pollutants, and encouraging the use of renewable energy sources.

Cleaner gasoline was made widely available in all or part of 16 states, including much of the Northeast and California in early 1995, primarily to reduce the emissions of smog causing pollutants, and to reduce overall smog levels. RFG is quite effective at reducing smog precursors such as volatile organic compounds (VOCs), and oxides of nitrogen (NOx). The first phase of the RFG program (1995-1999) required that volatile organic compound emissions be reduced by 17 per cent, and NOx by 1.5 per cent. The second phase of the program began this year, and requires further emission reductions of 27 per cent for VOCs, 22 per cent for toxics, and a 7 per cent for nitrogen oxides; this action is estimated to be equivalent to taking more than 16 million vehicles off the road.

The introduction of the second phase of the RFG program has been complicated by significant fouling of groundwater supplies by one RFG agent used in the current gasoline supply, Methyl Tertiary Butyl Ether (MTBE), in several parts of the United States, including several areas in California, as well as Maine and New Hampshire. MTBE is also a suspected human carcinogen.

Neither the Clean Air Act nor other actions of the EPA require the use of MTBE in RFG; rather, the Clean Air Act Amendments required that the RFG contain a minimum of 2 per cent oxygenate content by weight. No individual oxygenate is specified for use; however, both ethanol and MTBE are currently used successfully in the RFG program, with fuel providers choosing to use MTBE in about 80 per cent of RFG.

In response to concerns associated with the use of oxygenates in gasoline, the USEPA established a blue-ribbon panel of leading experts from the scientific community, water utilities, environmental groups and local and state government agencies, to discuss and formulate solutions on issued posed by the use of oxygenates in gasoline. Reporting in July of 1999, the panel stated that RFG has provided significant reductions to the emissions from vehicles, but the use of MTBE has resulted in growing incidence of detectable concentrations of MTBE in drinking water. The panel presented several recommendations to the USEPA Administrator for possible implementation. They include:

• Enhanced water protection and monitoring programs.
• Prevention of gasoline leaks through improvement of existing programs.
• Remediation of existing contamination.

• Amend the US Clean Air Act to remove the requirement that federal reformulated gasoline contain 2 per cent oxygenate by weight.

• Maintain current air benefits.
• Reduce the use of MTBE.
• Accelerate research on MTBE and its possible substitutes.

On March 20, 2000 the Clinton Administration announced that the USEPA will move to reduce use of MTBE on grounds that it poses a public health risk to humans and the environment. As the gasoline additive is linked to groundwater pollution in California and other states, the USEPA announced they will seek to "significantly reduce or eliminate" within three years, the use of MTBE under the Toxic Substance Control Act, which allows the USEPA to ban any substance proven to be an unreasonable risk to the public.

The agency will also ask Congress for changes in the Clean Air Act that would encourage the use of ethanol, a gasoline additive derived from corn, instead of MTBE, since a 1990 law requires the use of oxygenates in fuel in several parts of the country.

Two Northeast states, New Hampshire and New York, continue to consider the implementation of lower groundwater and drinking water standards for MTBE. Currently, New Hampshire has a drinking water standard of 70 ppb and New York has a groundwater standard of 50 ppb. The new lower standards proposed are 13 ppb for New Hampshire and 10 ppb for New York State.