In 2009, the State of California adopted Sediment Quality Objectives (SQO), which are narrative objectives established to protect benthic communities from direct exposure to toxic pollutants in sediments. SQOs incorporate multiple lines of evidence to assess the health of the Estuary’s sediment. The Southern California Coastal Water Research Project (SCCWRP) developed a sediment quality assessment tool to implement SQOs in a consistent manner. The assessment tool analyzes three lines of evidence (sediment chemistry, sediment toxicity and benthic community condition) to determine contamination effects. The three lines of evidence are integrated and consequently each station is given an categorical station assessment:
2) Likely Impacted
3) Possible Impacted
4) Likely Impacted
5) Clearly Impacted
The RMP will perform SQOs (using SCCWRP's sediment quality assessment tool) on all 2011 and 2012 sediment samples, collected under the status and trends (S&T) monitoring program.
Although SQOs for bays and estuaries have been adopted, staff from the RMP, SCCWRP, the State Water Resources Control Board, Regional Water Quality Control Board, the USGS, and Department of Water Resources have been meeting to determine how additional SQO assessments will be conducted. The RMP has convened a number of benthic workshops to discuss the development of benthic indices for the oligohaline (freshwater) and mesohaline (moderately saline) portions of the Estuary.