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BLUE RIDGE ENVIRONMENTAL DEFENSE LEAGUE To: Citizens for a Safe Environment From: Louis Zeller Re: GWI response to questions about gasification Date: April 12, 2002 Thank you for providing to me a copy of Global Waste International’s March 28th letter to the Duplin County Board of Commissioners. I write to provide additional information on gasification and to show that GWI’s answers are incomplete and misleading. I have addressed questions 3, 4, and 5 below. 3. GWI said that "starved air gasification is distinguished from mass burn incineration by the EPA." GWI admits gasification is "technically incineration" but that it is held to different standards. In fact, the US EPA distinguishes mass burn incinerators and starved air gasification units by the amounts of pollution emitted; that is, both mass burn and gasification combustors emit the same pollutants into the atmosphere, but in different amounts. For example, EPA data show that gasification units emit more nitrogen oxides and dioxins than incinerators, and equal amounts of mercury.1 Compared with incinerators, gasification combustors emit 28% more nitrogen oxides. NOx contributes to smog, or ground-level ozone pollution. According to EPA, children and adults with lung disease or asthma, and those who work or exercise outdoors risk lung damage from NOx pollution.4 Mercury air emissions from gasification units and mass burn incinerators are equal and would be 204 pounds per year at a 100 ton/day combustor. NC toxic air pollutant regulations indicate that mercury is unhealthy above 0.6 parts per billion.5 The US ATSDR states, "Even at low levels, metallic mercury can cause health problems. Metallic mercury exposure can cause harm before symptoms arise." 6 Gasification units emit 83% more furans and dioxins than mass burn incinerators. Dioxin is one of the most toxic substances known; there is no safe level. Dioxin is a "known human carcinogen."3 4. In Mr. Gavin’s letter, GWI "certifies that the volume reduction of the MSW is approximately 90% with 100% recovery of all aluminum, other metals, and glass." To find out more about recycling with gasification, we interviewed C. Lowell Miller, a gasification fuel systems expert with the United States Department of Energy. Asked about metal and glass reprocessing after gasification, Mr. Miller said, "It seems to me a difficult thing to do. The materials would be in one great big clump."2 He said that high temperatures would also fuse sand or earth in the waste into glass. He added, "It could be difficult to process the ash because of the components [in the slag]."2 We asked if recyclable materials could be recovered. Mr. Miller said, "Aluminum would not, it would be melted."2 5. GWI states that ash would not meet the definition of hazardous waste as defined by the EPA. According to solid waste fuel studies, ash produced by the burning of solid waste contains on average the following elements in parts per million (ppm): lead 220 ppm, chromium 92 ppm, cadmium 6 ppm. Assuming GWI’s 90% reduction of waste volume at a 100 ton per day unit, 3650 tons of ash and residue, or 7.3 million pounds, would be produced annually. (100 tons x 365 days x 0.1 = 3650) The gasification unit’s annual ash output would contain 44 pounds of cadmium, 671 pounds of chromium, and 1,606 pounds of lead. If it is not considered hazardous waste, the ash could be buried in a nearby solid waste landfill where it would contaminate leachate and groundwater. Further, the safety of use of ash containing toxins in building materials is debatable; the question is controversial in communities throughout the United States. Incineration and gasification are two sides of the same coin. Both have smokestacks which emit pollution into the atmosphere. Both burn the same type of fuel: municipal solid waste. Both expose waste to similar temperatures: 1000 to 1600 degrees F. Therefore, it should be no surprise that the lists of toxic air pollutants emitted by both are identical. Pound-for-pound comparisons of the levels of emissions from gasification units and incinerators are for some compounds higher, some identical, and some lower, but in every case represent an unnecessary risk to environmental quality and public health. Enclosure: Incineration and Gasification: A Toxic Comparison: a detailed investigation of air pollution emissions from mass-burn incinerators and starved-air gasification combustors. Footnotes 1. US Environmental Protection Agency, Compilation of Air Pollutant Emission Factors, Volume 1, Fifth Edition, AP-42 2. C. Lowell Miller telephone interview with Louis Zeller on March 29, 2002 3.Report on Carcinogens, Ninth Edition, Revised January 2001, U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program 4. US Environmental Protection Agency, Office of Air & Radiation http://www.epa.gov/air/urbanair/nox/hlth.html 5. NC Air Pollution Control Requirements, 15A NCAC 2D.1104 6. National Alert: A Warning About Continuing Patterns of Metallic Mercury Exposure, Agency for Toxic Substances and Disease Registry and USEPA, 7. http://www.atsdr.cdc.gov/alerts/970626.html 7. Refuse-Derived
Fuel Processing, Floyd Hasselriis,
Appx C, Source: US Bureau of Mines Publication RI
8426
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