Texas Environmental Almanac, Chapter 6, Air Quality, Page 7

MAJOR STATIONARY SOURCES

For these reasons - the emission of criteria air pollutants and toxics - these industrial facilities, which the Federal Clean Air Act calls "major stationary sources," are often the focus of state and citizen efforts to reduce air pollution. In fact, major industry bears the administrative burden of obtaining permits and, particularly in the non-attainment areas, must reduce emissions significantly. This section takes a look at three categories of major-stationary-source air pollution: manufacturing, combustion and mechanical facilities.

Despite the large amount of effort spent by the state in issuing permits, violations of permits and state air quality regulations are fairly common. In the ten year period between September 1982 and August 1992, there were more than 23,000 violations issued by the Texas Air Control Board. Over this period, around 3,400 violations were for failure to obtain a permit prior to construction or operation of a facility.(113) Other common violations included nuisance violations, violating the conditions of a permit, creating a traffic hazard, failing to report upset air emissions and violating federal toxics emission standards. Most of these toxic emission standard violations were violations of the asbestos demolition or renovation standards which did not result in significant air emissions.

Source: Texas Air Control Board, Texas Air Control Board Violation Detail Report (TACB, August 11, 1992).

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MANUFACTURING INDUSTRIES

Texas' major industries are concentrated along the Gulf Coast and in major metropolitan areas like Dallas-Fort Worth, El Paso, Midland-Odessa, San Antonio and Austin. The amount and type of pollution varies widely by region. For example, Corpus Christi's major industries - oil and gas refineries, pipelines, and chemical companies - contribute an estimated 41 percent of total volatile organic compounds and 62 percent of nitrogen oxides emitted in the Corpus Christi area every day. In Austin, major industries - mainly electronics manufacturers - only contribute 1 percent of the area's total VOC emissions and 14 percent of nitrogen oxides emissions.(115) Not surprisingly, much of the concern over industrial air pollution has been along the Gulf Coast.

Toxic air emissions from these industries are a major concern of citizen groups around the state. Federal law requires manufacturing industries with more than nine employees to submit data on releases of more than 300 toxic chemicals and 20 chemical compounds. Harris, Jefferson and Galveston counties are among the top ten emitters of toxics per year in the country.(116)

Many of these toxics have been linked to both cancer and birth defects. In 1992, the chemicals known to cause, or suspected of causing birth defects - categorized as either developmental toxins or heritable mutagens by the EPA - which were released into the environment in the greatest amount included toluene, xylene, methyl ketone and trichloroethylene. Most of these releases were through the air.

There are, at present, no state or federal regulations specifying acceptable ambient concentrations for air toxics, as there are for the criteria pollutants. For example, only one of the top 15 toxic chemicals released in Texas, benzene, has been the subject of a national air quality standard. By comparison, five of these 15 toxic chemicals have maximum contaminent level standards established under the Safe Drinking Water Act.(117) However, the air permitting requirement that new permitted facilities use best available control technology (BACT) limits toxic emissions considerably. Also, the 1990 Clean Air Act will impose new standards on industries identified as sources of 189 major toxic compounds. In addition, the TNRCC has developed a system to evaluate concentrations of more than 1,500 chemicals, including the top 15 toxic chemicals, emitted by permitted facilities. Guideline concentrations called ESLs, previously described, are used to evaluate not only proposed emissions but also ambient air monitoring data.

Toxic air emissions reported to both the state's Emissions Inventory as well as under the Toxics Release Inventory Program do not include "upset" emissions. Defined as accidental, unplanned air pollution releases, thousands of upsets a year contribute pollutants to the state's atmosphere. Under state regulations, companies are required to report their upsets to the TNRCC. But the information in these reports is sketchy: a 1992 Sierra Club survey of upset emissions in nine Texas counties revealed that companies do not always report or even know in some cases how much or what type of chemical was emitted.(118) According to this study, of 8,857 upset reports in 1991, 80 percent did not list the quantity of compound released, and 38 percent did not report the type of chemical released.(119) Such accidents and failure or inability to report accurate upset emissions make it extremely difficult to assess the full impact of industrial toxic emissions on public health. In addition, because the state does not set levels or limits on upset emissions - by definition they are unplanned events - the data these reports do contain are not used to help set emission limits.

COMBUSTION

A second category of major stationary sources is made up of facilities that burn material for energy, waste disposal or both. Utilities, waste incinerators, industrial boilers and cement kiln facilities are the major examples. Because these facilities burn materials at very high temperatures, they emit chemicals and gases that sometimes result in dangerous chemical reactions. For example, sulfur dioxide is one of the principal compounds emitted from electric utilities. When hot, a small portion of sulfur dioxide emissions can combine with oxygen to form sulfates, which in turn can combine with water particles to form sulfuric acid. This acid falls to the earth as acid rain.(120) Sulfur dioxide and nitrogen oxides, both of which contribute to the formation of acid rain, and carbon dioxide, a greenhouse gas, are the major pollutants resulting from combustion. Heavy metals are also emitted by some combustion facilities. Coal-burning facilities can emit mercury and cadmium. Cement kilns and incinerators for hazardous waste and municipal waste can all emit chromium, manganese and lead.

Texas has 27 major electric utilities operating 312 generating stations.(121) About half of the state's electricity is derived from coal, about 40 percent comes from natural gas, and the remainder comes from hydroelectric power, nuclear power and renewable energy sources.(122) Electric utilities that use coal as their combustible material pump millions more tons of carbon dioxide, sulfur dioxide and nitrogen oxides into the atmosphere than do those using natural gas or a combination of petroleum and natural gas.

In 1990, the generation of electric power produced 35 percent of all the carbon dioxide and 66 percent of all the sulfur dioxide emitted in the state.(123) In fact, the four facilities in Texas which released the largest volume of criteria pollutants are all coal-fired electric power plants.(124) Emissions from power plants contribute to the formation of smog and acid rain.

Under the 1990 Federal Clean Air Act, in order to combat acid rain formation, sulfur dioxide emissions must be reduced by 10 million tons below 1980 levels and nitrogen oxide emissions must be cut by 2 million tons by the year 2000. In a first phase, the nation's largest 110 utilities (none of them located in Texas) must achieve the greatest share of sulfur dioxide reduction by the end of 1995. In a second phase, all other major utilities, including those in Texas, must reduce sulfur dioxide emissions. The Clean Air Act also caps the amount of sulfur dioxide utilities can emit in 2000, and places controls on nitrogen oxide emissions as well. Major utilities in Texas will soon be required to continuously monitor and report their emissions and, like major industries, will also be required to obtain a federal operating permit.

Waste incinerators are another source of combustion-generated air pollutants. Both municipalities and industries sometimes incinerate a variety of waste as a means to reduce their volume and to generate energy. Public opposition to such facilities expressed at permit hearings has raised awareness about the air pollution that can result from these facilities, particularly hazardous waste incinerators, which burn waste that are defined as hazardous because they are toxic, flammable, corrosive and/or reactive. There are currently 32 permitted hazardous waste incinerators in Texas. Harris County, with 13 facilities, has more hazardous waste facili-ties than any other county in the United States. Jefferson County, with five, is among the top ten.(125) These facilities are operated by large corporations, chiefly to dispose of their own waste. Three of the facilities presently operating in Texas are commercial waste incinerators, accepting liquid waste from both in-state and out-of-state generators.

Cement plants are combustion facilities on a smaller scale. Some burn hazardous waste to fire their kilns. In 1991, citizen groups in Midlothian, near Dallas, expressed concerns about health effects from the burning of hazardous waste in cement kilns and the dumping of cement-kiln ash in quarries. Two of the three cement kiln plants in the Midlothian area were burning waste-derived fuels.(126) A third had previously burned tires to generate energy and was seeking a permit to continue burning them. Responding to citizen concerns, the Texas Air Control Board monitored community air for particulate matter, metals, sulfur compounds, air toxics and other compounds. Monitors were located downwind of the major facilities in the area. Tests conducted over a two-year period indicated that no adverse health effects are expected to result from exposure to the monitored levels.(127)

MECHANICAL

Industries that rely on mechanical processes include: metal smelters, grain elevators, foundries, steel manufacturers, wood processors, cotton gins, asphalt batching operations, concrete and cement batching operations, paper mills, sand blasting operations and oil and gas rigs. These industries are another major category of stationary sources that can pollute the air. Cotton gins, for example, may lead to heavy emissions of particulate matter. In 1990, air sampled around a cotton gin in the Lower Rio Grande Valley showed respirable particulate matter was being emitted in high levels, although not in violation of standards applicable to agricultural sources.(128) Lead smelters are of particular concern to citizens living near them and to environ- mental groups. As an air pollutant, lead is emitted in particles so small that 50 percent might remain in the lungs if breathed by humans.(129) However, tests conducted by the Texas Air Control Board in response to citizen complaints found that levels of lead in the ambient air near the smelters were below national air quality standards.(130) Any lead smelters built after 1987 must be at least 3,000 feet from the nearest residence.(131)

Texas Environmental Almanac, Chapter 6, Air Quality, Page 7

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