Current NADP sample processing at the Wisconsin State Laboratory of Hygiene (WCAL) integrates processes and procedures previously implemented by the Illinois State Water Survey (ICAL), while incorporating selected new and innovative approaches. Several modifications to the initial sample processing steps, which include sample receiving, data entry, pH and conductivity measurement, and sample filtration, have been implemented. The WCAL has initiated same day processing (pH and conductivity determination and filtration) upon sample receipt. Manual pH and conductivity procedures have been optimized and now only require a total of 10 mLs per sample. The Titrec Automated Electro-Chemistry Analyzer was upgraded and is being phased-in to replace both manual pH and conductivity measurements. Filtration methods have been simplified, including reducing low volume sample dilutions to 25 mLs, while still incorporating the filtration apparatus used by the ICAL.  After extensive validation, modifications to certain supply preparation and shipping protocols have also been implemented. Further improvements in supply preparation and shipping are being explored.

After initial processing, samples are ready for analyte measurement. WCAL utilizes similar analytical platforms to ICAL.  This includes the Agilent 5110 ICP-OES, two Lachat QuickChem 8500 Series 2 instruments and two Thermo Fisher/Dionex Integrion HPIC instruments.  These analytical platforms are well established and are used by EPA, State, and NELAC accredited laboratories (including the WSLH).  At this time WCAL has not modified any specific analytical chemistries.  However, QA/QC practices have been modified in relation to instrument calibration, sample duplicates, filter and method blanks, and tier 1 level data review processes.  WCAL is in the early stages of evaluating viable analytical options to improve detection limits, sample throughput, and expansion of the ICP-OES element menu.  These alternatives include utilizing a 2 cm flow cell on the FIA systems, and exploring a concentrator and high sample output analytical columns on the IC.