Bivalve Monitoring: Figure 4.13

Tables

Figure 4.13. Total PCB 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. S = Compounds generally comprising a significant portion of sum not quantifiable, sum not calculated. 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. Bivalves were not deployed at Grizzly Bay (BF20) in the dry season due to a lack of species from a "clean" source. The Grizzly Bay (BF20) data for the wet season cannot be used due to contamination at the reference site Lake Chabot. 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 0.39 (depuration) to 54.47. Median concentrations were highest in C. fluminea in the wet season, intermediate in C. gigas, and lowest in M. californianus in the dry season. The highest measured concentration was in C. gigas, at Coyote Creek (BA10) in the wet season.

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