at Manasquan Inlet and grid cell 100 is at Deal Lake. The lateral limits of 
southern borrow site holes are at cell numbers 25 and 52. 
72. Classical geometrical wave theory predicts waves will diverge 
behind a hole. Wave height will be lower directly in the shadow of the hole 
and greater at the sides, where waves that are refracted outward by the hole 
and waves that are directly incident will combine. Since waves diverge out- 
ward from the center line of a hole, the directions of waves that have passed 
over the hole will be of opposite sign with respect to the center line. 
73. The results shown in Figures 14 and 15, and in Appendix F exhibit 
the general characteristics of refraction over a hole as described in the 
previous paragraph. In Figure 14a, the change in wave height at the approx- 
imate center of the borrow hole has a maximum negative value as expected, and 
lobes appear on each side. The side toward Sandy Hook has two major lobes 
caused by the irregular plan shape of the hole. The changes in wave direction 
at the 3-m depth, given in Figure 14b, show waves positively directed on the 
south side of the hole and negatively directed on the north side. The lobe 
with a positive change in direction (on the south side) is higher because the 
waves are incident out of the east. 
74. From Figure 15, it is seen that the two southern holes approxi- 
mately act as one unit. By comparison to Figure 14, the smaller areal extent 
and smaller dredged depth of the southern site limit changes in the wave 
properties near shore. Another mitigating factor is the greater ambient depth 
in which the southern borrow holes are located. 
75. The following list gives a summary of results obtained from the 
wave refraction analysis: 
a. A (divergence) region of lower than average refracted waves 
exists at a location roughly along the centerline of the borrow 
site hole(s). A major lobe of higher than average waves exists 
at both sides of the divergence region. The refracted wave 
direction goes through zero in the divergence region and is 
opposite in sign on either side. 
Io 
The region of significant change in refracted wave height and 
direction is relatively insensitive to deepwater incident wave 
direction. This region remains localized directly landward of 
the hole and has lateral (longshore) dimensions of the order of 
the lateral dimensions of the hole. 
Changes in refracted wave height and direction are small for 
short period (4-sec) waves and increase with the wave period. 
The rate of increase of changes in wave properties decreases as 
the wave period increases, however. Thus, the change is larger 
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