Following the initial volume decrease on 24 July, accretion occurred through- 

 out the disposal period and continued into the early postdepositional period. 

 Inshore accumulation at the end o£ that time was similar to the inshore volime 

 just before the earlier erosion event. Following this accretion trend, erosion 

 of the inshore ensued and continued until late in the postdisposal period, the 

 loss being similar to the earlier amount of possible storm loss. By mid-October, 

 inshore zone had again accreted. 



The inshore zone contained the surf zone bar and trough. The time-sequence 

 profiles show that these elements underwent significant modification following 

 disposal. Volume changes were plotted for the three shore-parallel subzones 

 comprising the inshore zone (Fig. 18, C, D, and E) . These subzones correspond 

 to the predisposal trough, surf zone bar, and bar flank position. Volume trends 

 for the subzones reflect the shape modification of each profile element. The 

 trough filled and the bar eroded at a high rate during the last of the disposal 

 period and early postdisposal period. Later in the postdisposal period, volume 

 change in the initial bar and trough positions were minimal and remained that 

 way throughout the study period. 



(4) Beach . The beach accreted during the disposal period to the early 

 postdisposal period, then showed slight erosion. Overall, there was net ac- 

 cretion for the entire period of beach measurement. Volume change for subzones 

 of the beach showed greater buildup in the backshore than the foreshore. Overall 

 buildup of the backshore, including a slight volume decrease with time, corre- 

 sponded to development and migration of the beach ridge. The net buildup of the 

 foreshore subzone is related to infilling of the inner margin of the trough, 

 which is included in that general subzone. 



d. Textural Change . The predisposal profile was characterized by an over- 

 all textural trend in which sediment size decreased from coarse- and medium- 

 sized sand on the beach, to fine-sized sand in the inshore zone, to fine- and 

 very fine-sized sand in the offshore zone (Fig. 19). Three zones of local 

 coarsening occurred within this overall trend. The zone of coarest material,' 

 with grain sizes ranging into the coarse sand class, was associated with the 

 swash zone. The other two zones, showing only a slight coarsening, occurred in 

 the surf zone trough and just seaward of the surf zone bar. In most locations, 

 the sand was well sorted (Fig. 20). Poor sorting values were associated with 

 the coarse sand in the swash zone. 



Following sampling of the predisposal profile range -5+00, dredged sediment 

 was placed in what was then the upcurrent direction (southwest), > 15 meters from 

 the sampled profile near profile range -6+00 (Fig. 19). No sediment was placed 

 along the previously sampled native profile. The disposal sediment was coarser 

 (composite Mn = 1.04 phi, 0.49 millimeter) and less well sorted (composite Scf) = 

 1.02) than the native sand. The texture of the disposal sediment was most 

 similar to the coarse, poorly sorted sediment of the swash zone. 



Seven days following sediment disposal, profile -5+00 was resampled. A 

 coarse textural anomally had developed across part of the earlier fine-grained 

 inshore and offshore zones. This new coarse zone was characterized by fine- to 

 coarse-grained, poorly sorted_sand (Figs. 19 and 20, A-A'). Relatively large 

 ripples (L = 25 centimeters, H = 5 centimeters), some asymmetric with steep sides 

 landward, developed in the coarser zone replacing small-scale ripples (L = 5 

 centimeters, H = < 1 centimeter) of the previously fine-grained bottom. The 



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