57_ 



than 14 cms" 1 , maximum suspended particulate concentrations varied between 1 and 

 10 mg l" 1 with no apparent correlation with significant wave height (Figure 3-12); it is likely 

 that wave period, duration of maximum wave height, and other factors play a major role in 

 the near-bottom energy affecting sediment resuspension. Furthermore, as shown for storms 

 5 and 6, the availability of fine-grained sediment deposits also plays a role in suspended 

 particulate concentrations in the near-bottom water column. 



Also shown in Table 3-5 are the duration of elevated suspended particulate 

 concentrations, the maximum SDCS value, and a comparison of (pre-storm) background and 

 (mid-storm) maximum particulate concentrations for each of the nine storms at PDS. 

 Although these results do not represent a robust dataset for conducting statistical analyses or 

 additional analyses of near-bottom physics, they do reveal the complexity of this multi- 

 parameter problem and contribute valuable information for the design of future measurement 

 programs and/or numerical modeling focused on sediment resuspension at PDS (e.g., Gailani 

 1997). 



Oceanographic Measurements at the Portland Disposal Site during Spring of 1996 



