Our Experience

Low-Level Storm Water Runoff Requirements for PCBs

New state and federal limits for storm water runoff with possible PCB contamination require analysis by EPA Method 1668 for PCBs. The Part Per Quadrillion (PPQ) method detection limits require modification to Method 1668 to account for potential background contamination.

The Client

Federal and State Facilities

The Challenge

The total PCB concentrations that are present in the day-to-day operation of a laboratory could affect sample data causing a high bias result. This high bias result could cause a failure to meet federal or state storm water runoff criteria.

CFA Services Provided

To meet agency requirements, the GEL/CFA team developed a protocol for calculating a statically valid total PCB background value.  This value is monitored per matrix on a daily, weekly, and monthly basis.

The Result

The GEL/CFA team presented the background protocol to federal and state agencies for discussion and approval. After receiving approval from all parties, the background protocol was then submitted for third party data validation and agency quality review.  All of these agencies approved the background study for implementation in the laboratory.  The GEL/CFA LIMS programing team provided total PCB background results using Method Blank (MB) concentrations. MB total PCB concentrations can be reported on a daily, weekly and monthly basis using rolling averages. Custom reporting formats allowed MB total PCB average concentrations to be displayed on the sample report forms, subtracted from individual sample concentrations, or reported separately.  Systematic data processing shows data transparency and reproducible calculation verification for all data reviewers involved. The GEL/CFA quality team provided support and training for all agency and third party validators to ensure that all data quality standards could be verified independently.