EPA is amending its hazardous waste regulations under Subtitle C of the Resource Conservation and Recovery Act (RCRA) for testing conducted to evaluate a solid waste for the Toxicity Characteristic.

Specifically, this rule removes the quality assurance (QA) requirement found in Method 1311, Toxicity Characteristic Leaching Procedure (TCLP), for correcting measured values for analytical bias (also referred to within this rule as spike recovery correction). However, this rule retains appropriate QA provisions, including that matrix spike recoveries be calculated and that the method of standard additions be employed as the quantitation method for metallic contaminants when appropriate as specified in the method.

• Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Toxicity Characteristic Revision - Federal Register Notice, November 24, 1992 (PDF)(4 pp, 10 K, November 24, 1992, FR Vol. 57, No. 227)