L-7 
Table 3. Percent of the stratum placed into the sediment contaminant effect 
group using the contaminant discriminant function of Dauer et al. 2002 
(posterior probability > 0.5). Data from 1996-2002. Elizabeth River data 
includes the intensive 1999 event and 25 random samples of the watershed 
from 2000-2002. 
Stratum 
N 
Percentage of stratum 
in Contaminant Group 
Lower (VA) Mainstem 
175 
10.9 
Upper Bay Mainstem 
175 
17.7 
MD Eastern Tributaries 
175 
16.6 
Patuxent River 
175 
20.0 
MD Middle Mainstem 
175 
17.1 
MD Western Tributaries 
175 
24.6 
Potomac River 
175 
31.4 
James River 
175 
30.9 
Rappahannock River 
175 
37.1 
York River 
175 
38.3 
Elizabeth River 
275 
52.4 
% of stratum 
Figure 2. Percentage of stratum with a B-IBI value < 2.7 and placed into the 
Contaminant Group with a posterior probability > 0.5. 
appendix 
Addendum to the Report 
