Bivalve Monitoring: Figure 4.12

Tables

Figure 4.12. Total PAH concentrations in parts per billion dry weight (ppb) in three transplanted bivalve species at 15 RMP stations during the wet- and dry-season sampling periods. Note different y-axis scales. There were no samples for Yerba Buena Island (BC10), Red Rock (BC60), Petaluma River (BD15), Davis Point (BD40), and Napa River (BD50) in the wet season due to zero percent species survival. Petaluma River (BD15) also had zero percent survival in the dry season. In the dry season, the Grizzly Bay data could not be used due to a high contamination at the "clean" site. Bivalves were not deployed at Grizzly Bay (BF20) in the dry season due to a lack of species from a "clean" source.T-0 (time zero) is the initial concentration before deployment in the Estuary. T-0 values are missing for C. fluminea for the dry season because the population at Lake Chabot crashed before sampling. Accumulation factors ranged from 0.57 (depuration) to 47.42. Median concentrations were highest in C. gigas during the dry season, intermediate in C. fluminea, and lowest in M. californianus during the wet season. The highest measured concentration was in C. gigas, at Coyote Creek (BA10) in the dry season.

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