Industrial Facility – Treatment Media – Unexpected Characteristic Hazardous Waste Determination
The RCRA regulations require that any person who produces or generates a waste must determine if that waste is hazardous. In some situations this determination can be quite complex. Cox-Colvin was retained by an active Midwest solid waste disposal firm to characterize a spent landfill gas treatment media. The initial evaluation by the facility indicated that a single metal analysis significantly exceeded the TCLP limit. A second sample was collected and analyzed by the facility with similar results. Generator knowledge, based upon similar use at other facilities, suggested the spent media was not a listed waste or a characteristically hazardous waste. Costs associated with hazardous waste disposal placed the long-standing gas treatment technology at risk.
After verifying that the laboratory had performed the tests properly, Cox-Colvin reviewed the treatment system design and past operational information to develop a waste characterization plan. The plan followed EPA waste characterization guidance and utilized data quality objectives (DQOs). The DQO process is particularly well suited to address problems of this type, which require making a decision between two clear alternatives.
The statistically based sampling plan was designed to:
- meet a high level of statistical confidence while balancing decision errors because the consequences of making a type II error (that the media is identified as non-hazardous when it is actually hazardous) are severe;
- maintain a reasonable number of characterization samples and sampling events.
The characterization plan was implemented by Cox-Colvin and representative samples were collected. Following analysis, the analytical results were validated and statistically analyzed by Cox-Colvin. The results demonstrated that the treatment media was not characteristically hazardous.