Appendix 3: Determination of TSS and POC Blank Corrections for the ACT 2006 Turbidity Sensor Verification.

Abstract

As part of the field deployment test for this turbidity sensor verification study, each test site determined TSS and POC concentrations on between 40 – 60 samples. Sampling and analytical methods for these parameters are outlined in the document, Protocols for the ACT Verification of In Situ Turbidity Sensors (ACT PV06-01), which can be downloaded at (www.actus.info/evaluation_reports.php). While ACT makes no claim that data derived from in situ turbidity sensors should directly correlate with total suspended solids (TSS) or particulate organic carbon (POC), these parameters were designated as useful ancillary data to characterize the abundance, and to a course extent, the type of particulate matter present in the test environments during the performance evaluation. Therefore, considerable effort was made to ensure and report the highest quality TSS and POC data possible. ACT applied site specific blank corrections to the raw data for both parameters in order to adjust the values to reflect truer, mean values. Toward this end, we also derived more conservative estimates of variance (as standard deviation) about these corrected means.