Frequent Questions

Should a generator use grab samples or composite samples to determine compliance with the land disposal restrictions (LDR) treatment standards?

In general, a generator should use grab samples to determine compliance with LDR treatment standards. Where performance data exists based on both the analysis of composite samples and the analysis of grab samples, EPA establishes the treatment standards based on the analysis of grab samples. Grab samples normally reflect maximum process variability and thus, would reasonably characterize the range of treatment system performance (55 FR 22520, 22539; June 1, 1990).
In cases where only composite data exists, EPA considers the QA/QC of the data, the inherent efficiency of the process design, and the level of performance achieved. EPA may then choose to use this composite data to develop the treatment standard. Where these data are used to establish the treatment standard, the treatment standard is identified as based on the analysis of composite samples. Enforcement of that standard would also be based on composite samples (55 FR 22520, 22539; June 1, 1990).
 Therefore, a generator should use grab samples to determine if a hazardous waste meets the applicable treatment standards. However, if a treatment standard is based on the analysis of composite samples, then a generator can use composite samples to determine compliance with that treatment standard.

Have more questions? Submit a request