ReactivityQuestion: What is the current guidance regarding the reactivity characteristic? I heard that EPA had withdrawn the method for Reactive Cyanide and Reactive Sulfide as specified in Chapter 7 of SW846. Is this true?
Answer: 40 CFR Section 261.23 includes 8 different properties of a waste which is hazardous because of the characteristic of reactivity. A waste is a reactive hazardous waste if it exhibits one or more of those properties. The regulations do not require specific test methods for any of these properties. Therefore, generators must use waste knowledge to determine if their waste exhibits the characteristic of reactivity.
According to property (5) under 261.23, a waste is hazardous if it is a cyanide- or sulfide-bearing waste which generates toxic gases or vapors at a quantity sufficient to present a health danger. In July 1985, EPA issued interim guidance describing certain threshold levels for cyanide- and sulfide-bearing wastes and laboratory methods for evaluating such wastes. In April 1998, EPA withdrew the July 1985 guidance. Therefore, EPA does not recommend use of the interim threshold levels or methods to determine if a waste is hazardous based on the characteristic of reactivity. In the near future, EPA will be removing the guidance threshold levels and the laboratory methods from Chapter Seven of SW-846. A copy (PDF) (8 pp, 18K, About PDF) of the EPA memorandum which withdrew the reactivity characteristic guidance is now available for downloading.