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Significant or Potentially Significant
Impacts of CRDRP |
Can an Alternative Avoid or Minimize
Adverse Impact of CRDRP? Is the Impact Reduced to Less than Significant |
Feasibility and Other Effects of
Alternatives to CRDRP That Avoid or Minimize Impacts |
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Hydrology |
(See end notes for definition
of Options 1-4) |
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H1. In drought years only, lack of flow to the
lagoon in certain months. (See SEIR Appendix C, Impact C.3.1-1.) |
- In general, Options 1-4 could reduce the
number of months with no flow (by up to 4 months) as compared
to CRDRP, but could not mitigate the impact to less than significant.
- In dry years, only Option 2 would provide
year-round flow.
- In critically dry years, Options 1-4 would
result in at least 4 months with no flow.
- In severe years, all options would result
in at least 9 months with no flow.
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Cost: Options
1-4 are more costly than CRDRP; capital costs are 8–25%
higher, O&M costs are more than five times higher, and net
present value is more than twice as expensive as CRDRP.
Site: Questionable
feasibility for desalination plants over 6 MGD; must find adequate
well sites for Seaside injection; must confirm dredging disposal
area. Availability of land, once located, must be confirmed. |
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Infrastructure:
Large desalination project and injection require significant
new Cal-Am distribution facilities.
Plan Consistency:
Large desalination project may not comply with regional Air Quality
Management Plan. |
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Jurisdiction Boundary: Large desalination project sites are outside of MPWMD
boundaries; MPWMD policy is to develop feasible resources within
boundary first. Cal-Am may be able to purchase these sites.
Property Ownership:
Applicant does not own desalination sites (increasing competition
among agencies), new injection well sites and dredging disposal
area. |
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Environment:
Concern about desalination impacts to energy use, coastal dunes,
sloughs, and ocean species near discharge of brine; massive traffic
impacts of dredging. See items below for more information.
Water Supply:
Reliability in extended power outage a concern under Options
1-4, but not with CRDRP; superior drought protection under Options
1-4. |
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Fish and Aquatic Life |
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F3 In severe drought periods (such as 1987–1991),
reduced opportunity for upstream migration as compared to "natural"
(unimpaired) conditions. (See SEIR Appendix D, Impact D.4.1-1.) |
- In general, Options 1-4 could provide 1 to
3 more attraction days per season than CRDRP, but no option mitigates
the impact to less than significant (i.e., provides attraction
opportunities similar to natural flows).
- In dry years, CRDRP and Options 1-4 are very
similar and provide 40% fewer attraction opportunities than natural
flow.
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See item H1 above for general overview of options.
Options 1-4 provide similar benefits and impacts for smolt emigration
as CRDRP; in an extended drought like 1987–1991 period,
options perform better than CRDRP in some years and worse in
others. The CRDRP is superior to all options in providing summer
flow for juvenile steelhead rearing. |
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- In critically dry years, when every opportunity
is crucial, Options 1 and 2 would provide four attraction days
compared to two for CRDRP, but would still fall short of 6 days
with natural flows.
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F5 Reduction in winter and spring peak flows
could change substrate conditions in three river reaches, and
potentially reduce the abundance and diversity of insect food
resources for juvenile steelhead in those areas. (See SEIR Impact
D.4.2-4.) |
- It is assumed that this impact would be mitigated
to a less-than-significant level with Options 1 and 2, and possibly
Options 3 and 4.
- Options 1 and 2 would function similarly
to the existing situation in terms of peak flows. No option would
include a storage reservoir to trap flows; diversion for Seaside
Basin injection is very small compared to peak flow rates.
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See item H1 above for general overview of options.
Options 3 and 4 (which include dredging) could possible result
in adverse sedimentation impacts to downstream fishery habitat
(and habitat for food resources). |
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- It is possible that increased storage in
Los Padres Reservoir with Options 3 and 4 could affect peak flows,
but not to the same degree as with CRDRP. Detailed computer simulations
are required to confirm assumptions.
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Vegetation and Wildlife |
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VW6. Stress to riparian vegetation and wildlife
habitat in drought years as a result of reduced water table (See
NLP Impact 9.3.1-8.) |
- In general, Options 1-4 would reduce the
severity of drawdown as compared to CRDRP, but cannot fully mitigate
the impact, especially in Aquifer Subunit 4 (AQ4).
- Only Option 2 could fully mitigate impacts
in Aquifer Subunit 3 (AQ3) in all water year types; other options
reduce effects in dry and critically dry years in AQ3.
- No option can mitigate impacts in AQ4 for
all years; Options 2-4 alleviate drawdown impacts in dry years
only; adverse effects remain in critically dry and severe year
types.
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See item H1 above for general overview of options. |
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Traffic |
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T1. During construction period, increased traffic
levels on Highway 1 and Carmel Valley, Cachagua and Tassajara
Roads; potential damage to roadways from heavy vehicles. (See
SEIR Chapter 4, Impacts 4.2.3-1 through 4.2.3-3.) |
- Options 1 and 2 would avoid traffic impacts
on Carmel Valley area roads.
- Options 3 and 4, which include dredging Los
Padres Reservoir, would result in more severe traffic impacts
on Carmel Valley area than with CRDRP. Impact of years of continual,
high-density truck traffic was identified as a major concern
in dredging feasibility studies. (See discussion in Appendix
A, Section A3.3.)
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See item H1 above for general overview of options.
Desalination construction could potentially affect traffic along
coast, north of Seaside. |
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Climate/Air Quality |
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CA1. During construction period, increased regional
air pollutant emissions from vehicles and equipment, smoke from
burning, and fugitive dust. (See SEIR Chapter 4, Impact 5.2.2-1.) |
- Options 1-4 would avoid emissions associated
with construction clearing and grubbing reservoir (burning).
However, regional emission impact is likely for construction
of large desalination plant, appurtenant pipelines and other
facilities.
- Long-term operation of desalination plant
could result in noncompliance with regional Air Quality Management
Plan as identified in 1993 EIR for 3 MGD desalination project;
energy use associated with large desalination projects in Options
1-4 would exacerbate this situation.
- Options 3 and 4 (which include dredging)
would result in higher emissions and dust associated with trucking,
and for a longer duration than with CRDRP.
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See Item H1 above for general overview of options. |
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Noise |
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N1. During construction period, noise levels
in the project vicinity would be increased as a result of construction
traffic and activities in the staging area. (See SEIR Chapter
6, Impacts 6.2.2-1 and 6.2.2-2.) |
- Options 1-2 would avoid noise in Cachagua/Carmel
Valley area.
- Options 3 and 4 (which include dredging)
would result in more frequent and longer duration of noise in
Cachagua and Carmel Valley areas associated with trucking than
with CRDRP.
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See Item H1 above for general overview of options.
Desalination project construction could result in noise elsewhere;
plant operation is very loud unless proper acoustic protection
is provided (see 1993 desalination project EIR). |
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Visual Quality |
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V1. Construction activities will alter existing
visual conditions in the project area and result in more nighttime
light; the new dam will permanently alter the viewshed in the
project vicinity. (See SEIR Chapter 9, Impacts 9.2.2-1 and 9.2.2-2.) |
- Options 1 and 2 will avoid visual effects
of dam.
- Options 3 and 4 (which include dredging)
could affect visual quality in Cachagua area due to chronic trucking
for many years.
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See Item H1 above for general overview of
options.
A large desalination plant could affect visual
quality elsewhere but adverse effect is unlikely due to location
of plant in industrial areas. |
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Cultural Resources |
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CR2. Loss, damage or disturbance of Esselen cultural
properties (traditional cultural properties) or setting for properties
in project area. (See SEIR Chapter 7, Impacts 7.2.3-1 through
7.2..3-5.) |
- Options 1 and 2 will avoid adverse effects
of CRDRP on Esselen cultural resources.
- Certain identified resources in existing
reservoir inundation area could be destroyed or lost due to dredging
in Options 3 and 4.
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See Item H1 above for general overview of
options.
A large desalination plant could potentially
affect cultural resources of other Native American groups, especially
in Moss Landing area. Preliminary surveys do not indicate serious
concerns; additional surveys would be required. |
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Public Health and Safety |
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PH1. Increased risk to worker and public safety
during construction. (See NLP Impact 15.3.1-1.) |
- Options 1 and 2 will avoid safety effects
related to dam construction in Cachagua area.
- Options 3 and 4 (which include dredging)
would result safety hazards in Cachagua and Carmel Valley area
due to chronic trucking for many years.
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See Item H1 above for general overview of options.
A large desalination plant poses worker safety concerns during
construction and operation. |
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Land Use, Planning, Recreation |
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L2. Recreation at Cachagua Community Center and
park, and nearby residences affected by construction traffic,
noise, dust. (See SEIR Appendix F, Impact F-2.) |
- Options 1 and 2 would avoid recreation impacts.
- Options 3 and 4 could exacerbate adverse
impacts due to trucking associated with dredging. See discussion
for Traffic, Climate/Air Quality and Noise.
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See Item H1 above for general overview of options. |
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L3. Inundation of portions of Carmel River Trail
(public access route through private land to Ventana Wilderness);
restricted access during construction. (See SEIR Appendix F,
Impacts F-3 and F-4.) |
- Options 1-4 would avoid inundation impacts
to Carmel River Trail.
- Options 3 and 4 (which include dredging)
may impair use of existing road to Los Padres Dam (the beginning
of trail access) due to truck traffic.
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See Item H1 above for general overview of options. |
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Growth Inducement |
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GR1. Project could indirectly result in release
of estimated 799 af of metered sales for new connections and
remodels by MPWMD, contributing to adverse regional traffic and
air quality impacts. (See SEIR Chapter 10, Impact 10.4.1.) |
- Options 1-4 could each result in growth inducement
of 799 af of metered sales compared to 778 af of metered sales
with CRDRP, which would be an adverse impact.
- Options 1-4 also have excellent drought protection
performance that could enable release of water presently set
aside for drought protection.
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See Item H1 above for general overview of options. |