Frequent Questions

Does the U223 hazardous waste code apply to virgin toluene diisocyanate (TDI) that has been neutralized to remove the reactivity characteristic?

The U223 waste code may apply to toluene diisocyanate (TDI) if it is an unused commercial chemical product (CCP) that is being discarded. A CCP is a substance that consists of the commercially pure grade of a chemical listed in 40 CFR §261.33, any technical grades of the chemical, and all formulations in which the chemical is the sole active ingredient (§261.33(d))(54 FR 31335, 31336; July 28, 1989). 

The pure form of a chemical is a formulation consisting of one hundred percent of that chemical. The technical grade of a chemical is a formulation in which the chemical is almost one hundred percent pure, but contains minor impurities (Memo, Lowrance to Wayland; May 3, 1988 (RCRA Online #11348)).
 A chemical is the sole active ingredient in a formulation if that chemical is the only active ingredient serving the function of the formulation. However,  if a formulation contains more than one active ingredient, the formulation would not fall within the scope of the listing in §261.33, regardless of whether only one or both of the active ingredients are listed (Monthly Call Center Report Question; March 1992 (RCRA Online #13530)).
A mixture of a solid waste and a hazardous waste listed solely for the characteristic of ignitability, corrosivity, or reactivity is no longer a hazardous wastes if the mixture does not exhibit the hazardous characteristic (§261.3(g)(2)(i)). The same rationale applies when a waste meets a listing description, but does not exhibit a characteristic of hazardous waste at the point of generation (Monthly Call Center Report Question; October 2002 (RCRA Online #14638)).
There are currently twenty-nine wastes codes within the RCRA program listed solely for the characteristic of ignitability, corrosivity, or reactivity (66 FR 27266, 27283; May 16, 2001). However, U223 is not one of these twenty-nine wastes codes because it was not listed solely for exhibiting the characteristic of reactivity. It was listed because it is both reactive and toxic (§261.33(f)). Therefore, the U223 waste code would apply to the discarded toluene diisocyanate if it is an unused CCP even when it’s reactive properties have been removed or neutralized.

The Federal Register dated May 16, 2001 (66 FR 27266) is available at the following URL:
www.gpo.gov/fdsys/pkg/FR-2001-05-16/pdf/01-11411.pdf

Additional guidance regarding the applicability of P and U listed waste codes is available in the following documents:

Monthly Call Center Report Question; August 1996 (RCRA Online #14012)
Memo, Dellinger to Smith; March 18, 2003 (RCRA Online #14654)
Memo, Barnes to Mastalerz; August 21, 1989 (RCRA Online #11459)
Memo, Barnes to Fox; May 19, 1988 (RCRA Online #11350)

These documents are available at the following URL: : https://yosemite.epa.gov/osw/rcra.nsf/how+to+use?OpenForm

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