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Severn Trent Laboratories (STL) is largest group of environmental analytical laboratories in the United States. These laboratories come from diverse backgrounds and offer a full range of complimentary services that make STL the leader in the industry.

STL-Knoxville is a full-service environmental analytical laboratory providing services to consulting firms, government and industry. Their specialty organics laboratory offers the analysis of dioxins and furans in a variety of environmental matrices by high-resolution gas chromatography/mass spectrometry. This capability has also been employed in the ultra-trace analysis of PCB’s, PAH’s and pesticides.

Bill Waddell spent over ten years building and supporting an environmental laboratory information management system in a company with similar capabilities. This specific experience, coupled with his knowledge of legacy operating systems, made him a perfect match for STL-Knoxville’s needs.

In mid-1999, Waddell Software Development LLC was contracted to review the data retrieval and transfer processes and design programming changes to eliminate the need for operators to manually input data. The system was designed by WSD president Bill Waddell and written in Visual Basic at the customer’s request.

The set of conversions programs named IsoCalc has been successfully installed at STL-Knoxville to automate the data handling for the analysis of dioxins and furans. The operators can now select a sample batch, review the Peak List and assign specific compound names to any of the peaks. After identifying peaks, the operator can display a Result List displaying only those compounds of interest with corresponding Retention Times, concentration, detection limit, recovery percentage and any applicable flags. Once approved, the results are stored in a local server to be collected soon after by the centralized corporate computer network. Click here to see a one-page turnaround time analysis which demonstrates the striking impact IsoCalc has had on the reduction of processing time.

Waddell Software Development LLC also provided written User Manuals, program based Help files and trainer assistance to support the success of this conversion. In addition, test scripts were designed and tested prior to installation to validate the programs.

In 2001, the programming partnership continues as Waddell Software Development in collaboration with the staff at STL-Knoxville modify IsoCalc to automate the data retrieval and reporting of samples analyzed by US EPA Method 1668A for HRGC/MS of PCBs. This will give STL-Knoxville the capability to report all 209 specific PCB congeners.