2.0 Alternatives Considered
sites to observe the discharged material. Appropriate communication equipment (two-way radios or
cellular telephones) would allow for communication with dredge personnel. Daily ship logs shall also be
maintained regarding the dredge position, time and sediment depth of dredge activities. If the monitor
observes cultural material suggesting that dredging has entered an archaeological site, then the dredging
operation would be permanently relocated away from that site and a 250-foot-wide buffer would be
established around the site. The location of the site would be recorded for the appropriate clearinghouse.
The monitoring program would be guided by the probability for occurrence of archaeological resources.
Where there is a high probability of occurrence, the monitor would be present during dredging of the
borrow sites (cutterhead dredge) or when material is being pumped to the receiver site (hopper dredge),
on a daily basis. This applies to SO-9 at depths below nine feet, SO-6, MB-1 at depths below 12 feet
and SS-1. Where the probability is moderate, the monitor would be present as above on alternate days.
This applies to SO-9 at depths higher than 9 feet, SO-7, SO-5, and MB-1 at depths greater than 12 feet.
2.5.2
Post-Construction Monitoring
There will be monitoring, and may be mitigation, for potential indirect impacts to sensitive marine resources
due to sedimentation and indirect impacts to lagoons from increased sand inflow. Each is discussed
individually below.
Potential Sedimentation Impacts to Marine Resources
Sensitive marine resources are defined consistent withthe Navy's documentation (1997a, 1997b) as rocky
intertidal reefs; subtidal vegetated reefs including feather boa kelp, surfgrass, sea fans, and sea palm; and
nearshore kelp. These resources exist in an environment of constantly moving sediment. The fluctuation
is daily and seasonal. Most have adapted to periodic exposure to sand, while some experience total
covering. Seasonal fluctuation of up to three feet has been documented (Appendix D). Therefore, the most
difficult challenge in designing a sediment monitoring programis distinguishing project-related sediment from
natural seasonal sand flux. Toward that end, the monitoring program includes pre-discharge baseline
studies and post-discharge monitoring as well as monitoring of control sites that are not influenced by the
project, but are comparable in terms of other ocean influences. The existing data collected by Navy will
serve as one component of the pre-discharge baseline data and as a guide for the monitoring program
overall. All monitoring data from the on-going Navy monitoring are publicly available as would be the
results of the proposed monitoring program.
Regional Beach Sand Project EIR/EA
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