Pilot Studies

Mercury Deposition Network

Authors: Don Yee (SFEI)

One pathway of pollutants to the Estuary is atmospheric deposition, which was examined in the RMP Atmospheric Deposition Pilot Study. That study was suspended after metals (including mercury) and PAH/PCB data were incorporated into the mass budget models, indicating that atmospheric deposition is not a primary source or pathway for most of these contaminants, with the exception of PAHs. The only remaining component to the study is the continued measurement of rain samples for mercury as part of the national Mercury Deposition Network (MDN) at a station at NASA Ames (MDN CA 72) through 2004, a five-year commitment made at the start of the RMP study. Pending approval by the TRC, RMP will continue data collection at this MDN station for 2006.

The continuing objectives of this monitoring are to:

  • Evaluate concentrations of mercury in rainwater as part of TMDL refinement
  • Contribute to the national database to evaluate contributions of mercury from large urban areas and long-range aerial transport from outside the region to surface waters

Winter Pilot Study

Authors: Sarah Lowe (SFEI)

In 2005, the first year of a two-year winter pilot study was conducted. Estuarine water was sampled at three historical RMP stations (i.e., Sacramento River (BG20), Yerba Buena Island (BC10), and Dumbarton Bridge (BA30)) during the 2005 winter season (February 2005). These water samples were analyzed for contaminants on the California Toxics Rule priority pollutant list.

Wet weather S&T contaminant monitoring is potentially an important element of the RMP. At the present time, the annual S&T monitoring occurs during the dry season, and seasonal variation is not captured by this sampling plan. The results from this Pilot Study will enable SFEI to evaluate the spatial and temporal trends of pollutants in the winter. Wet season monitoring results have been an important resource provided to environmental managers of Region 2 for use in NPDES permitting and the 303(d) listing processes.

A workgroup will be convened in October 2005 to discuss the winter sampling needs for 2006 and beyond. A key discussion point for this meeting will be understanding regulatory needs and assessing whether the scope of the pilot study needs to be expanded to additional sites or matrices. Changes to the scope of the Winter Pilot study will need to be discussed and approved by the TRC and SC.

Exposure and Effects

In 2006, the RMP will continue the Pilot Study of contaminant exposure and effects in the Bay. The 2003 RMP Program Review Panel recommended an increase in the Exposure and Effects Pilot Study (EEPS) budget and stated that biological effects research should be a priority. In response to this concern, the SC increased the funding for the EEPS budge to $200,000 per year and extend the pilot study through 2008. This budget includes funds for SFEI labor, subcontractors (e.g., analytical laboratories), and direct costs.

The Study is multifaceted, and has included a variety of different exposure and effects indicators of beneficial use impairment. The purpose of EEPS is to develop suite of environmental indicators that can be incorporated into the core Status and Trends monitoring program.

Special Studies

Contaminant Loads from the Sacramento and San...