55 



REMOTS® data collection activities were abbreviated by the onset of a winter storm 

 during the February 1996 baseline survey. Three replicate photographs were obtained 

 from 24 stations surrounding the PDA buoy, with deteriorating weather conditions 

 precluding the collection of images from the final nine stations. All 33 stations were 

 occupied during the subsequent November 1996 precap and postcap surveys. All 

 REMOTS® sediment-profile photographs were analyzed for the presence of dredged 

 material and its sedimentary characteristics. A time series, based on evidence of dredged 

 material deposition, was then constructed for each station from the REMOTS® 

 photographs. 



3.5.2 Planview Photography 



As part of the February 1996 baseline REMOTS® survey over the Royal River 

 Project Area, a series of planview photographs of the PDS seafloor were obtained. The 

 sediment-profile camera frame was equipped with a Photosea® 1000 A Underwater Camera 

 System and deployed along the NW/SE transect of the REMOTS® sampling grid. An 

 independent trigger mechanism allowed the planview camera and strobe to fire 0.5 to 1.0 

 seconds before the REMOTS® camera touched down, providing undismrbed images of the 

 bottom. The planview photographs were later correlated with the corresponding 

 REMOTS® sediment-profile data through time and replicate notations for point 

 characterization of the PDS seafloor (Figure 3-5). 



The Portland Disposal Site Capping Demonstration Project, 1995-1997 



