2.0 Alternatives Considered
Spawning Grunion
Replenishment of beaches could potentially bury grunion eggs or change the beach profile such that juvenile
grunion are unable to return to the ocean. Monitoring would occur during discharge operations at those
receiver sites with suitable grunion habitat. Monitoring by a qualified biologist would only occur during the
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spawning season (March through August) and during the dates specified by the CDFG in their annual
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pamphlet Expected Grunion Runs. If grunion were observed spawning, disposal of sand would cease
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in the vicinity and a buffer zone established. The buffer zone would extend 65 feet shoreward of the high
water mark at the spawning area and 100 feet upcoast and downcoast (total 200 feet). A sand dike would
be constructed to ensure that discharge water would not enter the spawning area. A schematic drawing
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of any diked buffer area would be submitted to the resource and regulatory agencies. The buffer zone
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would be in place a minimum of 14 days to allow the eggs to hatch, and surveys show no subsequent
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spawning has occurred in the same area.
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Underwater Cultural Resources
Underwater culturalresources consist of potential archaeological resources and historic elements remaining
at ancient river bed locations. The dredge areas at each borrow site have varying potential to effect such
resources. Although the dredge areas have been designed, to the maximum extent possible, to avoid
locations of high probability for underwater archaeological resources there is the potential for such
resources to be uncovered during dredging. Design considerations to avoid high probability areas are
constrained by ocean outfalls, artificial reefs, and kelp beds as well as the location of beach quality sand.
Identified side scan sonar targets in SO-9 and MB-1 would be investigated by diver or remotely operated
vehicle (ROV) prior to dredge to determine what they are. Interpretation of sonar targets is difficult and
targets within the dredge area may be gravel, sand dollar beds or historic features. If the targets are historic
features, then a buffer would be established around the target and the resource would be recorded at the
appropriate clearinghouse. Interpretation of targets will be also be appropriate to avoid any features that
may hinder or damage the dredge machine. Finally, complete side scan sonar will be obtained and
interpreted at SO-9 and SS- 1 prior to dredge activity to verify no historic targets and to ensure no
damaging features for the dredge.
To avoid significant archaeology impacts, monitoring will be required as material is dredged from each
borrow site. A qualified marine archeologist would be present while material is being placed on receiver
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Regional Beach Sand Project EIR/EA
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