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TONS OF HAZARDOUS WASTE
BURNED IN TEXAS, 1999
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Source: Texas Commission on Environmental Quality, Trends in Texas
Hazardous Waste Management Based on 1999 Numbers (2002), Tables 1, 3, 4 and 5; and TCEQ, "Hazardous Waste Management by County," STEERS Database, 2002.
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Incineration reduces and may, in some cases, eliminate hazardous characteristics of waste. In the case of
waste-to-energy facilities, it may also provide energy for use in other production processes. However, the burning of hazardous waste in incinerators, boilers, and
industrial furnaces (or BIFS) and in cement kilns—which burn waste to produce the clinker that makes cement—has been shown to increase the amount of toxics released to the air and in certain
cases the chemicals burned may produce even more toxic chemicals, collectively known as Products of Incomplete Combustion. In addition, the ash produced
by burning hazardous waste may still be a threat to human health and the environment because it contains such compounds as lead, uranium, and arsenic. Finally,
the variety of waste streams received at commercial incineration facilities makes it harder to control the burning process, leading to problems with explosions and toxic plumes.*
Until 1986 some utilities, industries, commercial facilities, schools, government institutions, and
apartment and home owners across the country burned hazardous waste and used oil for energy recovery purposes.* Today, non-industrial facilities—homes,
apartments, schools—are not allowed to burn hazardous wastes or used oils containing toxics. Industrial facilities using hazardous waste or used oil must comply with
certain standards and register with both the EPA and the state.*
In 1999 about 1.1 million tons of hazardous waste were incinerated or burned for energy or thermal recovery at on-site
boilers and industrial furnaces in Texas.* An additional 275,000 tons were burned at captive or commercial facilities,
including cement kilns. More than 110,000 additional tons were "blended" at fuel blending facilities, which could then
send the waste to be burned at other facilities. There is an increasing reliance on the burning of wastes; 35 percent of
Texas-generated hazardous waste processed and treated off site in commercial facilities were burned or blended into fuels for later incineration.* This represents an increase from 1991, when about 28 percent of commercial management of hazardous wastes resulted in burning.*
Incineration has increased in Texas in large part because of the increase in commercial capacity at one cement kiln.* An increase in demand for incineration has also resulted from the federal land disposal rules, which require treatment
of hazardous wastes before land disposal. As land disposal has decreased, incineration and deep-well injection of
wastes have increased. Hazardous waste imported from out-of-state industries for incineration by Texas facilities
increased from 31,000 to nearly 75,000 tons between 1989 and 1997, although it then dropped to 43,000 by 1999,
mainly due to reduction of clean-up waste from a soil contaminated with PCB in New York State.*
Texas Industries Inc. in Midlothian, in Ellis County, is the only cement kiln in Texas that uses hazardous waste as fuel.
Two other cement kilns in Midlothian—Holnam, Inc., and North Texas Cement Co.—burn tires but are currently not
burning hazardous waste, in part due to community pressure against it. In 2002, TXI in Midlothian has also sought a
permit amendment to burn tires and conducted test burns. Fuel blending facilities mix a variety of liquid and solid
wastes to create a fuel that is then introduced into the kiln of the cement plant. The burning of hazardous wastes in
cement kilns creates two main waste "products"—air emissions from the stack, and cement kiln dust leftover from the
production of cement. A third product—the cement clinker itself—may also contain traces of hazardous waste.
In addition to Texas Industries, there are 30 hazardous waste incineration facilities located throughout the state. Most
of these hazardous waste incineration facilities are owned and operated by companies that treat waste on site from
manufacturing facilities owned by the same company. There are presently four commercial incinerators operating in
Texas -- Arch Chemicals (formerly Olin Corporation), Chemical Waste Management, Rhodia Inc. (formerly Rhone
Poulenc), and Safety Kleen (formerly Rollins)while two more—American Envirotech in Houston and Houston Chemical
Services in Pasadena—are permitted but not yet built. Another commercial facility, Olin Corporation in Jefferson County, is an industrial furnace used for sulfuric acid energy recovery.*
Cement kilns currently do not have to meet the same standards as commercial waste incinerators.* Up until recentlyk, the main regulations governing cement kilns that burn hazardous wastes are the 1991 Boiler and Industrial Furnace
Regulations. These regulations allow Texas Industries to burn hazardous wastes under an interim status in proximity to
populations without the same safety and monitoring standards as commercial incinerators. In 1996 the company
applied with the then-TNRCC for an RCRA Title C permit to burn hazardous wastes and to change the facility from
interim status to a fully permitted facility. In 1997, after residents and community organizations opposed the permit, the
State Office of Administrative Hearings began a contested-case hearing process to consider whether to recommend
granting or denying the permit. In 1999 the judges recommended approving the permit, and the TNRCC has done so.
Under the permit, TXI could burn more than 230,000 tons of hazardous waste per year, although they have been burning less than half that amount.
The 1990 Federal Clean Air Act requires both cement kilns and hazardous waste incinerators to install new pollution
control equipment—known as Maximum Achievable Control Technology—to lower air emissions. In 1996, the EPA first
proposed new standards for a variety of hazardous air pollutants, and that proposal was finalized in 1999. However,
the new standards were met by legal opposition from both environmnental and business groups, and on July 24, 2001,
the United States Court of Appeals for the District of Columbia Circuti granted the Sierra Club's petition for review and
vacated some portions of the rule. Finally, on February 14, 2002, EPA issued "interim" emission standards for waste
combustion facilities. Under these interim standards, most facilities had to comply with the new rules by September 30th of 2003.* The new MACT standards are significantly stricter than the old BIF regulation emission limits, and will
reduce some toxics such as dioxins by more than 40 percent. Still, it is important to note that even under the new
standards, hazardous waste-burning cement kilns are not required to meet the same emission standards as
incinerators, giving cement kiln operators a regulatory and financial advantage over incinerators in the burning of hazardous wastes.
Another source of contamination from cement kilns burning hazardous wastes is cement kiln dust, or CKD. When the
RCRA was amended in 1980, the law stated that cement kiln dust—unlike incinerator ash—would not be considered as
hazardous waste until the EPA undertook a study to determine its human health and environmental impacts. Despite the
amendment, the EPA took no action for over a decade. A 1989 lawsuit led to a requirement that the EPA study the
problem and come up with regulations by January of 1995. The resulting 1993 EPA study found that cement kiln dust
was contaminated with dioxins, cadmium, chromium, and lead, among other heavy metals.* In addition, the study
documented 14 cases in which cement kiln dust had contaminated aquifers of surface waters, and 36 cases in which it had led to air pollution.* In August of 1999, EPA proposed standards for CKD waste which would allow CKD waste to be
managed as non-hazardous waste as long as certain performance and technology standards were met. Nonetheless,
the EPA still has not finalized regulations for the disposal of cement kiln dust and instead -- in July of 2002 -- issued a
new proposal which recommended allowing the waste to be continued to be treated as nonhazardous waste, and
studying for the next three to five years the CKD practices and regulatory programs to make sure that mismanaged
waste should not be considered hazardous. Under the proposal, the EPA would study the results of this interim approach and come up with further recommendations in 2005.* Even under the interim proposals, disposal and
management costs would increase significantly for cement kilns using hazardous waste fuels, although not as much as
if final regulations had required treatment similar to that required for hazardous waste incinerator ash.*
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THE DRY PROCESS OF A TYPICAL CEMENT KILN
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- Ground limestone and other raw materials are placed in rotating kiln.
- The ground materials are heated by fuel (which can include hazardous wastes), introduced at
the opposite end of the kiln.
- The final product, called "clinker" is cooled and later ground and mixed with gypsum to form cement.
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