Water Samples
Gas Bench II: Samples are analyzed in 12-mL vials with septa caps. If desired, our staff can pipet water samples to vials for a minimal charge per sample. In some cases, use of our pre-evacuated vials may be possible. Contact the lab manager for details.
TC/EA: We use a GC PAL autosampler and modified reactor for liquid injections on the TC/EA. Samples should be in 2 mL screw top vials (12×32 mm) with 8mm diameter septa caps. If desired, WSU laboratory staff can pipet samples into vials for a minimal charge. In the event of small samples, vial inserts can be used.
Dissolved Nitrate (NO3–): Dissolved nitrate is analyzed with the denitrifier technique, which results in conversion of NO3– to N2O using Pseudomonas aureofaciens. We use a modified Thermo GasBench II with Delta V IRMS for this analysis. Send filtered water samples frozen in well sealed and labeled vials. Generally 20mL of water is sufficient for multiple tests. Please provide sample nitrate concentrations when submitting samples. Inaccurate or absent concentrations may result in a duplicate analysis fee. We do not provide nitrate concentrations with results.