Ignitability, hazardous wastes

The generator of a waste must determine if the waste is hazardous. To do this, the generator must determine if the waste is specifically listed as a hazardous waste (Article 9, CCR), and/or if it is a characteristic hazardous waste (ignitable, corrosive, toxic, reactive) (Article 11, CCR). Certain wastes are also classified as "extremely hazardous wastes." These are listed in Article 9, CCR and their characteristics are identified in Article 11, CCR. 

Hazardous wastes are either listed wastes (40 CFR 261.30-.33) or characteristic wastes (40 CFR 261.21-.24). The U.S. EPA defines four characteristics for hazardous waste ignitability (40 CFR 260.21) corrosivity (40 CFR 260.22) reactivity (40 CFR 260.23) and toxicity (40 CFR 260.24). Any waste that exhibits one or more of these characteristics is classified as hazardous under RCRA. The ignitability definition includes a liquid that has a flash point less than 60 C (140 F) the EPA included ignitability to identify wastes that could cause fires during transport, storage, or disposal (e.g., used solvents). All of the solvents in Table 14.10.5 have flashpoints less than 60 C, so all could be a RCRA ignitability waste. 

If, after mixing a non-exempt characteristic hazardous waste with an exempt waste, the resulting mixture exhibits any of the same hazardous characteristics as the hazardous waste (ignitability, corrosivity, reactivity, or toxicity), then the mixture is a non-exempt hazardous waste. 

Thiophene and 3-methylthiophene are Hsted on the TSCA chemical substances inventory. Thiophene is regulated as a hazardous material under OSHA and also regulated under the Clean Air Act, Section 110, 40 CFR 60.489, but there are no exposure limits or controls set for 3-methylthiophene. Both materials are regulated under sections 311/312 of the Superfund Amendments and Reauthorization Act, 1986 (SARA), as materials with an acute health and fire hazard, and under the Resource Conservation and Recovery Act, as ignitable hazardous wastes (DOOl). 

Hazardous Wastes The U.S. EPA has defined hazardous waste in RCRA regulations, CFR Parts 260 and 261. A waste may be hazardous if it exhibits one or more of the following characteristics (1) ignitability, (2) corrosivity, (3) reactivity, and (4) toxicity. A detailed definition of these terms was first published in the Federal Register on May 19, 1980, pages 33, 121-122. A waste may be hazardous if listed in Appendix Wll. 

Small lab-pack containers of hazardous waste if they are first placed in nonlealdug, larger containers. These containers must be Filled to capacity and surrounded by enough absorbent material to contain the liquid contents of the lab pack. The resultant container must then be placed in a larger container packed with absorbent material which will not react with, become decomposed by, or ignited by the contents of the inside containers. Incompatible wastes may not be packed and disposed of together in this manner. 

The testing of chemicals/wastes to establish the nature of their hazard capacity/threat in accordance with regulatory requirements falls into four categories (1) reactivity, (2) ignitability/flammability, (3) corrosivity, and (4) EP toxicity. Commercial chemical products, specific wastes, and wastes from specific processes may be listed as hazardous wastes because they are known to present toxic hazards in the manner of the tests above and/or are known to present serious toxic hazards to mammals/humans. In the discussion to follow, various chemical groups will be examined primarily in the context of reactivity, ignitability, and corrosivity. 

Notification to the NRC is required for releases equal to or greater than the reportable quantity of a RCRA hazardous waste. If the waste also is on the CERCLA list, that reportable quantity applies. If not, the reportable quantity is 100 pounds if the waste is ignitable, corrosive, reactive, or toxic. 

Soil Cleanup, or remediation, of hazardous waste sites will often produce contaminated soil. Contaminated soil must be handled as hazardous waste if it contains a listed hazardous waste or if it exhibits a characteristic of hazardous waste. As with hazardous waste, land disposal of hazardous soil is prohibited until the soil has been treated to meet LDR standards. These contaminated soils, due to either their large volume or unique properties, are not always amenable to the waste codespecific treatment standards. Because of this, U.S. EPA promulgated alternative soil treatment standards in 268.49 in May 1998. The alternative soil treatment standards mandate reduction of hazardous constituents in the soil by 90% or 10 times UTS, whichever is higher. Removal of the characteristic is also required if the soil is ignitable, corrosive, or reactive. 

A waste is a hazardous waste if it is listed or is identified for ignitability, corrosivity, or both. 

Under the authority of the RCRA, a solid waste would be defined as hazardous if it exhibits any of the four (ignitability, corrosivity, reactivity, and toxicity) characteristics used to identify hazardous wastes. 

A solid waste containing lead or lead compounds may be defined as a hazardous waste if it exhibits the characteristic of toxicity. The waste is said to exhibit the toxicity characteristic if the lead concentration in the extract obtained by subjecting a sample of the waste to the TCLP exceeds 5.0 mg/L. Tetraethyl and tetraethyl lead are combustible. If they are in sufficient quantity in a waste, tetraethyl lead may show an ignitability characteristic. More details on the regulatory requirements are presented in Chapter 7. 

This statutory definition of solid waste is pursuant to the regulations of the EPA insofar as a solid waste is a hazardous waste if it exhibits any one of four specific characteristics ignitability, reactivity, corrosivity, and toxicity. 

The first step to be taken by a generator of waste is to determine whether that waste is hazardous. Waste may be hazardous by being listed in the regulations, or by meeting any of four characteristics ignitability, corrosivity, reactivity, and extraction procedure (EP) toxicity. 

There are four lists of hazardous wastes in the regulations wastes from nonspecific sources (F list), wastes from specific sources (K list), acutely toxic wastes (P list), and toxic wastes (U list) there are also the four characteristics mentioned before ignitability, corrosivity, reactivity, and extraction procedure toxicity. Certain waste materials are excluded from regulation under the RCRA. The various definitions and situations that allow waste to be exempted can be confusing and difficult to interpret. One such case is the interpretation of the mixture and derived-from rules. According to the mixture rule, mixtures of solid waste and listed hazardous wastes are, by definition, considered hazardous. Similarly, the derived-from rule defines solid waste resulting from the management of hazardous waste to be hazardous (40 CFR 261.3a and 40 CFR 261.1c). 

A waste stream may be defined as hazardous under RCRA if it meets certain criteria for ignitability, corrosivity, reactivity, or toxicity, or if the waste stream is specifically identified by EPA as a hazardous waste. An individual waste stream is subject to being classified as hazardous (listed) if it contains any one of approximately 375 chemicals identified by EPA as hazardous constituents. These designated chemicals are frequently referred to as Appendix Vlll compounds because of where they are listed in the published regulation. 

The hazardous waste identification regulations that define the characteristics of toxicity, ignitability, corrosivity, reactivity, and the tests for these characteristics, differ from state to state. In addition, concentration limits may be set out by a state for selected persistent and bioaccumulative toxic substances that commonly occur in hazardous substances. For example, the California Hazardous Waste Control Act requires the California State Department of Health Services (CDHS) to develop and adopt by regulation criteria and guidelines for the identification of hazardous wastes and extremely hazardous wastes. 

California criteria for defining hazardous wastes that are ignitable and reactive are identical to Federal criteria for hazardous wastes under RCRA defined at 40 CFR, Part 261. The California corrosivity criteria differ from the Federal criteria only in the addition of a pH test for nonaqueous wastes. 

A solid waste is considered hazardous if it is either a listed waste or a characteristic waste. Listed wastes include a list of specific processes that generate a waste and a list of discarded commercial chemical products. There are four hazardous waste characteristics ignitability, corrosivity, reactivity, and toxicity. The last refers to the leachability of a waste and the resultant toxicity in the groundwater using the analytical method referred to as toxicity characteristic leaching procedure (TCLP). A list of substances included under TCLP is shown in Table 1. 

Particular Attention Given to Hazardous Wastes. In addition to toxicity, hazardous wastes include materials that may become chemically reactive, including ignitability and explosibility, or that may be corrosive. Some toxic materials require extensive pretneatment prior to dumping. See Table 3 on p, 3701. 

Hazardousness Having a hazardous property. A chemical, procedure, or event that creates a substantial threat to human health and life. The United States Environment Protection Agency (US EPA) classifies hazardous wastes by four characteristics, including corrosivity (very alkaline (basic) (pH > 12) or acidic (pH 2) wastes), ignitability, toxicity, and reactivity (40 Code of Federal Regulations 261.20-261.24) (see Appendix E compare with toxicity characteristic and toxicity characteristic leaching procedure, TCLP). 

This Report is concerned with classification of hazardous wastes. Wastes are materials deemed to have no further beneficial use to their present custodian, although these materials may be useful to others. Unless otherwise indicated, the term hazardous as used in this Report refers to the presence of radionuclides, hazardous chemicals, or both. This term also may refer to certain characteristics of materials that pose a hazard, such as ignitability, corrosivity, or reactivity. 

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