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Region 9 Laboratory SOP 125
Aqueous Sample Disposal
Summary
Aqueous samples not used in the initial analyses are stored by the laboratory for a period of at least 90 days following the delivery of the data package to the Region 9 Quality Assurance Program (QAP). When samples are ready for disposal, the ESAT Health and Safety Coordinator, or designee, enters the analytical results of each sample into sample disposal report spreadsheets.
The analytical results are then reviewed and compared to federal, state and local regulatory limits. The sample disposal reports are submitted to the EPA Laboratory Safety, Health and Environmental Manager (LaSHEM) for review. After the LaSHEM indicates the sample disposal method, the reports are returned to ESAT.
Bulking and disposal methods for aqueous samples are determined by the detected levels of contamination for each sample, as well as the origin of the sample. In instances where water samples from NPDES or drinking water programs are found to contain concentrations of target analytes below applicable regulatory levels, the samples may, after approval by the LaSHEM, be neutralized and discharged to the city's sewer system. Sample digestate and extract disposal procedures are described in ESAT SOP 706, Laboratory Waste Management.