The information on this page is provided to help viewers to better understand the data download from the SFEI Contaminant Data Download and Display tool, including the type of data available and how data are presented and handled by SFEI. If you have questions or comments, please contact email@example.com.
Matrix Definitions: provides definitions used to identify the test material and matrix
Qualifier Definitions: provides information that should be considered when interpreting test results.
Data can be downloaded with all qualifiers or with a subset of primary qualifiers.
Results-Cross tab: data provided in a cross tabulated Excel worksheet
Results-Flat file: data provided in a flat file Excel worksheet
A CD3 download is provided as an Excel file, within which are separate worksheets containing the results in cross-tabulated and flat file formats. The flat file format is especially suitable for import into other software platforms, such as Access or SAS, for further analyses. A key to matrix and qualifiers is also included.
All qualifiers or only the "primary" qualifiers may be selected for display in the CD3 download. Primary qualifiers are DO, DOXXX, ND, NR, NRS, NRT, R, and SL. The primary qualifier SL is used to identify a significant toxicity test, for more information on the specific statistical comparison(s) conducted use the "Show All Qualifiers" option.
Information for percent solids, percent moisture, and percent lipids are reported only in the flat file Excel worksheet.
The results provided by CD3 may differ slightly from those previously reported in the RMP Annual Reports and static data tables, due in part to ongoing updates to the dataset, standardization of the qualifiers reported, changes in the handling of replicate samples, and changes in the method used to sum the dissolved and particulate water fractions.
Missing Data: Measurements vary by year and test material, but typically include a suite of contaminants (metals and organics) and ancillary data. Missing data are either not available (e.g., parameters were not measured in every year), or the data are being reanalyzed and will be made available at a later date. Missing data and changes in target RMP parameters are listed in the RMP Annual Monitoring Results reports.
SSC/TSS: Beginning in 2002, the water quality measurement total suspended solids (TSS) was replaced by the parameter suspended sediment concentration (SSC).
Organic Sums: Organic group sums, for example "Sum of PCBs (SFEI)", are calculated by SFEI based on the target analytes for an analyte group; the exact number and the group constituents may vary over the years.
Metal Data: All metals from 1993 to 2008 are reported as near totals. Beginning in 2009, water and tissue trace metals (Ag, Al, Cd, Cu, Fe, Pb, Mn, Ni, and Zn) are reported as total concentrations. Chemical analyses of sediment samples is generally performed on the <2mm fraction.
MDLs: While every effort is made to obtain the method detection limit (MDL) value from the labs, if none is available, other detection limits may be provided (e.g., instrument detection limit, sample detection limit, reporting limit). However, all detection/reporting limits are stored in the MDL field. Although some MDL values may appear truncated in the cross-tabulated output (e.g., 0.00), full results are provided in the flat file Excel worksheet.
Tissue Reference Sites: Two reference station codes (T-0 and T-1) are included in the tissue results for some years. T-0 indicates that the reference bivalve was analyzed before being deployed. T-1 indicates that the reference bivalve was analyzed after being deployed.
RMP Sampling Strategy: From 1993-2001 RMP sampling sites for water, sediment and bivalve tissue were at fixed locations throughout the Estuary. Starting in 2002 the RMP changed to a random sampling design for both water and sediment. The bivalve sampling sites remain at fixed locations. All sites, whether random or fixed, are associated with an Estuary region.
Beginning in 2009, the following three PCB Sums are reported:
During the analytical process, some PCB congeners (co-eluting PCBs) cannot be distinguished as separate congeners and thus are quantified as a complex of one or more congeners. When a reportable congener is co-eluting with another congener, we flag this result according to the following rules: