2000 Dioxin Data from Major Chlorine Producers and Users

Dioxin Data: Disposal of Dioxin to Underground Injection Wells and Landfills

This table displays quantities of dioxin disposed of in 2000 through EPA regulated disposal methods including hazardous and other types of landfills and underground injection wells¹. Landfills are carefully designed, using clay and polymer linings, covers and leachate drainage systems, to contain hazardous materials without leakage and contamination of the environment. Underground injection wells are used to bury materials well below the surface and away from drinking water sources. The US EPA defines five classes of underground injection wells according to the types of fluids injected as well and the underground injection location. These wells are regulated stringently under the Safe Drinking Water Act and the Resource Conservation and Recovery Act to prevent contamination of drinking water.

Disposal of Dioxin in 2000 to Landfills and Underground Injection Wells
	Toxic Equivalents (grams TEQ)	Total Mass (grams TM17)
Hazardous waste landfills (RCRA C, Sec 5.5.1A)
Other Landfills (Sec 5.5.1B)
Underground Injection Wells (Class I Wells Sec. 5.4.1)2
Underground Injection Wells (Class II-V Wells Sec. 5.4.2)3
Surface Impoundment (Sec. 5.5.3)
Other Disposal (Sec. 5.5.4)
Total Disposal in 2000

¹Figures rounded to two significant figures and totals may not equal sum of individual categories due to rounding.

²Class I underground injection wells emplace hazardous and non-hazardous waste fluids into isolated, porous formations beneath the lowermost potential underground source of drinking water in an area. They are the deepest class of injection wells, are technologically complex, and are strictly regulated under both the federal Safe Drinking Water Act (SDWA), which established the Underground Injection Control (UIC) Program, and the Resource Conservation and Recovery Act (RCRA). Liquid wastes injected into Class I wells are designed to remain isolated from human exposure for at least 10,000 years, during which time some wastes may chemically react to less toxic materials. The US Environmental Protection Agency (EPA) characterizes Class I underground injection wells as "…safer than virtually all other waste disposal practices" (US EPA, 1991).

³Class II wells include injection of fluids, mostly brines, used in oil and gas production. Class III wells are those associated with solution mining, in which injected fluids (which may be super-heated steam, water, or other fluids) are used to dissolve minerals for subsequent recovery on the surface. The fluids commonly are re-injected after extraction of the desired minerals. Class IV wells, banned except for special cases of groundwater remediation, address injection of hazardous or radioactive wastes into or above an underground source of drinking water. Class V wells encompass all underground injection not addressed in Classes I-IV. (US EPA)