Reportable Quantity for Hazardous Waste
Pipeline and Hazardous Materials Safety Administration · Nov 2, 1990 · Reference No. 90-0002
Interprets: 49 CFR § 172.101
Reggie’s quick take
Someone asked how to set the reportable quantity (RQ) for a hazardous waste stream. If the waste's constituents and their concentrations are known, use the RQ for each constituent, calculated from its concentration and the waste's net weight. In the asker's case, cyclohexane was the only known constituent, so its 1,000-pound RQ applies, not the waste stream's RQ. If the constituents or concentrations are unknown, use the RQ assigned to the waste stream, such as F001 with an RQ of 10.
Written by AI (Claude) on Oct 22, 2026. Robots make mistakes and leave things out, so the letter below is what counts. Not legal advice.
This is in response to your letter of March 15, 1990, regarding the reportable quantities (RQ) for hazardous wastes.
The appropriate RQ for a hazardous waste stream depends on the amount of information available on the waste stream (i.e., the constituents of the waste stream and their respective concentrations (percentages)). If the constituents of a waste stream and their respective concentrations are known, then the RQ for the individual constituents are used. Hazardous substance determinations are then made by using the concentration of each constituent and the net weight of the waste stream to calculate the weight of each hazardous substance that is present in the package. If the constituents or their respective concentrations are unknown, then the correct RQ is the RQ that is assigned to the waste stream. (e.g.. F001, RQ=10: F002, RQ=10). Information on determining the correct reportable quantity for hazardous wastes can be found in Docket 102RQ (50 FR 13456) published by EPA on April 4, 1985. An excerpt from the Federal Register publication is enclosed.
In the example presented in your letter, the RQ of 1000 pounds, which is the RQ assigned to cyclohexane should be used to determine if a package contains a hazardous substance. The RQ for the waste stream is inappropriate because the only constituent in the waste stream is known (i.e., cyclohexane).
I hope this satisfies your inquiry. If we can be any further assistance, please feel free to contact us.
A letter of interpretation applies the regulations to the facts the requester described. It isn’t a regulation and isn’t legal advice. The agency’s copy.