HomeMy WebLinkAboutPublic Review Draft ISMND
BIG CANYON HABITAT RESTORATION & WATER
QUALITY IMPROVEMENT PROJECT
Initial Study and Mitigated Negative Declaration
Prepared for February 2016
City of Newport Beach
Public Works Department
City of Newport Beach
100 Civic Center Drive
Newport Beach, California 92660
NOTICE OF INTENT TO ADOPT PROPOSED MITIGATED
NEGATIVE DECLARATION
In accordance with City of Newport Beach (City) policies regarding implementation of the California
Environmental Quality Act, the City has conducted an Initial Study to determine whether the following
project may have a significant adverse effect on the environment, and on the basis of that study hereby
finds:
D
l
The proposed project will not have a significant adverse effect on the environment;
therefore, it does not require the preparation of an Environmental Impact Report.
Although the proposed project could have a significant adverse effect on the
environment, there will not be a significant adverse effect in this case because the
Mitigation Measurns described in the fuitial Study have been incorporated as part of the
project. An Environmental Impact Report is therefore not required.
The Initial Study provides the basis and reasons for this detennination and is available in paper copy form
at the City of Newport Beach Public Works Department Counter, several public libraries, and online at
the City's website, as described below.
PROJECT:
Title: Big Canyon Habitat Restoration & Water Quality Improvement Project
Location: Within Big Canyon Nature Park, west and east of Jamboree Road and east
of Upper Newport Bay in the City of Newport Beach
Description: The proposed project encompasses 6 acres and includes the following (!)
restore historic riparian habitat by removing non-native vegetation and
replace it with native plantings, (2) stabilize the creek and floodplain, (3)
.iJnprove water quality in Big Canyon Creek and Newport Bay through the
addition of a water quality treatment bioretention cell, extension of the
Jamboree culvert, concrete stilling basin, and dosing station, and ( 4)
enhance public access within the Big Canyon Nature Park. The project also
includes maintenance of the proposed water quality features to ensure that
the features are functioning as originally designed.
Project Proponent: City of Newport Beach
Address: 100 Civic Center Drive, Newport Beach California 92660
Contact Person: Robert Stein Telephone Nun1ber: 949.644.3322
NOTICE:
The Initial Study is available for review by the general public. The Initial Study provides a detailed
project description and evaluation of the potential environmental effects of the proposed project. The
Initial Study can be accessed online at http://www.newportbeachca.gov/index.aspx?page=l347. Paper
copies are also avai lable at the City of Newport Beach Public Works Department, 100 Civic Center Drive,
Bay 2D, Newport Beach, Cal ifornia, 92660, and at the following l ocations:
N ewport Beach Public Library Newport Beach Public Library
Central Library Mariners Branch
1000 Avocado A venue 1300 Irvine A venue
Newport Beach, CA 92660 Newport Beach, CA 92660
Newpo1t Beach Public Library Newport Beach Public Library
Balboa Branch Corona del Mar Branch
100 East Balboa Boulevard 420 Marigold Avenue
Newport Beach, CA 92660 Corona del Mar, CA 92625
The City of Newport Beach requests your careful review and consideration of this notice, an d invites any
and all input and comments from intere sted Agencies, persons, and organizations regarding the Initial
Study/Mitigated Negative Declaration. Please s ubmit any comments in response to this notice no later
than 30 days beg inning on M arch 4, 2016 and ending the clos e of business on Apri l 4, 2016. All
comments or other responses to this notice should be submitted in writing to :
Robert Stein
Assistant City Eng ineer
City of Newport B each, Public Works Department
100 Civic Center Drive
Newport B each, California 92660
r stein@newportbeachca.gov
949.644 .3322
The d ecision-making body will review the Initial Study and potentially other sources of information
before considering the proposed project. The project s ite i s not presented on any li sts enumerated under
Sectio n 65962.5 of the Go vernment Code, including, but not limited to li sts of hazardou s waste facil ities,
land designated as hazardous property, and ha zardo us wa ste disposal sites .
The City of Newport Beach C ity Council is expected to deliberate on th e adoption of the Proposed MND
and approval of the project at its April 26 , 20 16 Council Meeting which begi ns at 7:00 p .m. in the City
Council Chambers at 'vie Center Drive, Newport Beach, California.
Signed: Dated: M arch 2, 2016
BIG CANYON HABITAT RESTORATION & WATER
QUALITY IMPROVEMENT PROJECT
Initial Study and Mitigated Negative Declaration
Prepared for February 2016
City of Newport Beach
Public Works Department
626 Wilshire Boulevard
Suite 1100
Los Angeles, CA 90017
213.599.4300
www.esassoc.com
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130934.00
TABLE OF CONTENTS
Big Canyon Habitat Restoration & Water Quality
Improvement Project Initial Study
Page
1. Introduction .....................................................................................................................1-1
1.1 Statutory Authority and Requirements ....................................................................1-1
1.2 Purpose ...................................................................................................................1-2
2. Project Description .........................................................................................................2-1
2.1 Introduction ..............................................................................................................2-1
2.1.1 Project Background ....................................................................................2-1
2.1.2 Purpose and Need for Project ....................................................................2-3
2.2 Project Location and Setting ...................................................................................2-5
2.3 Project Overview and Design ............................................................................... 2-10
2.4 Project Components ............................................................................................. 2-11
2.4.1 Creek Restoration, Creation and Riparian Habitat Enhancement .......... 2-11
2.4.2 Water Quality Improvements ................................................................... 2-18
2.4.3 Infrastructure Improvements .................................................................... 2-22
2.5 Construction Activities and Schedule .................................................................. 2-23
2.6 Project Operation and Maintenance .................................................................... 2-25
2.7 Project Approvals and Discretionary Actions ....................................................... 2-27
3. Initial Study Environmental Checklist ..........................................................................3-1
Environmental Factors Potentially Affected .....................................................................3-2
Environmental Checklist ...................................................................................................3-3
3.1 Aesthetics ......................................................................................................3-3
3.2 Agricultural and Forest Resources ................................................................3-5
3.3 Air Quality ......................................................................................................3-8
3.4 Biological Resources .................................................................................. 3-18
3.5 Cultural Resources ..................................................................................... 3-26
3.6 Geology, Soils, and Seismicity ................................................................... 3-31
3.7 Greenhouse Gas Emissions ....................................................................... 3-35
3.8 Hazards and Hazardous Materials ............................................................. 3-39
3.9 Hydrology and Water Quality ...................................................................... 3-43
3.10 Land Use and Planning .............................................................................. 3-48
3.11 Mineral Resources ...................................................................................... 3-50
3.12 Noise ........................................................................................................... 3-52
3.13 Population and Housing .............................................................................. 3-64
3.14 Public Services ........................................................................................... 3-65
3.15 Recreation ................................................................................................... 3-68
3.16 Transportation and Traffic........................................................................... 3-69
3.17 Utilities and Service Systems ..................................................................... 3-72
3.18 Mandatory Findings of Significance............................................................ 3-75
Big Canyon Habitat Restoration and Water Quality Improvement Project i ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
Table of Contents
Appendices
A. Operations and Maintenance Plan
B. Air Quality and Greenhouse Gas Modeling
C. Biological Resources Technical Report
D. Hazardous Materials Records Search
List of Figures
1 Regional Location Map .................................................................................................2-2
2 Project Vicinity Map .......................................................................................................2-6
3 Project Area Aerial ........................................................................................................2-7
4 Vegetation Communities Map .......................................................................................2-9
5 Project Components and Phasing ............................................................................. 2-13
6 Riparian Habitat Restoration Areas ........................................................................... 2-13
7 Habitat Mitigation Areas for Impacts to Jurisdictional Resources ............................. 2-17
List of Tables
2-1 Anticipated Reduction of Pollutants from Stormwater (Wet Weather) by the
Proposed Bioretention Cell ........................................................................................ 2-20
2-2 Preliminary Construction Duration ............................................................................. 2-25
3-1 Project Peak Day Construction Emissions ................................................................ 3-11
3-2 Concurrent Construction Peak Day Construction Emissions .................................... 3-12
3-3 Localized Construction Pollutant Emissions .............................................................. 3-15
3-4 Localized Concurrent Construction Pollutant Emissions ........................................... 3-15
3-5 Mitigation for Impacts to Vegetation Communities .................................................... 3-20
3-6 Summary of Impacts to Vegetation Communities ...................................................... 3-21
3-7 Permanent Impacts to Jurisdictional Areas ............................................................... 3-22
3-8 Mitigation for Permanent Impacts to Jurisdictional Areas .......................................... 3-23
3-9 Estimated Project Construction GHG Emissions ....................................................... 3-37
3-10 Genelan Plan Policy N1.8 dBA Increase ................................................................... 3-55
3-11 Construction Vibration Damage Criteria .................................................................... 3-56
3-12 Groundborne Vibration Impact Criteria for General Assessment .............................. 3-57
3-13 Vibration Source Levels for Construction Equipment ................................................ 3-57
3-14 Construction Schedule ............................................................................................... 3-59
3-15 Construction Equipment Usage and Noise Levels .................................................... 3-60
Big Canyon Habitat Restoration and Water Quality Improvement Project ii ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
CHAPTER 1
Introduction
The City of Newport Beach (City) has determined the proposed Big Canyon Creek Restoration
and Water Quality Improvement Project (project) is subject to the guidelines and regulations of
the California Environmental Quality Act (CEQA). This Initial Study addresses the indirect,
direct, and cumulative environmental impacts associated with the proposed project. The proposed
project includes the following (1) restore historic riparian habitat by removing non-native
vegetation and replace it with native plantings, (2) stabilize the creek and floodplain, (3) improve
water quality in Big Canyon Creek and Newport Bay, and (4) enhance public access within the
Big Canyon Nature Park. The project also includes maintenance of the proposed water quality
features to ensure that the features are functioning as originally designed.
1.1 Statutory Authority and Requirements
In accordance with the CEQA (Public Resources Code Sections 2100-21177) and pursuant to
Section 15063 of Title 14 of the California Code of Regulations (CCR), the City of Newport
Beach, acting in the capacity of Lead Agency, is required to undertake the preparation of an
Initial Study to determine if the proposed project would have a significant environmental impact.
If the Lead Agency finds that there is no evidence that the project, either as proposed or as
modified to include the mitigation measures identified in the Initial Study, may cause a
significant effect on the environment, the Lead Agency must find that the project would not have
a significant effect on the environment and must prepare a Negative Declaration or Mitigated
Negative Declaration for that project. Such determination can be made only if, “there is no
substantial evidence in light of the whole record before the Lead Agency” that such impacts may
occur (Section 21080(c), Public Resources Code).
The environmental documentation is intended as an informal document undertaken to provide an
environmental basis for subsequent discretionary actions upon the project. The resulting
documentation is not, however, a policy document and its approval and/or certification neither
presupposes nor mandates any actions on the part of those agencies from whom permits and other
discretionary approvals would be required. The environmental documentation and supporting
analysis is subject to a public review period. During this review, public agency comments on the
document should be addressed to the City of Newport Beach. Following review of any comments
received, the City of Newport Beach will consider these comments as part of the project’s
environmental review and include them with the Initial Study documentation for consideration by
the Planning Commission of the City of Newport Beach.
Big Canyon Habitat Restoration and Water Quality Improvement Project 1-1 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
1.2 Purpose
The City of Newport Beach (City) has prepared this IS/MND to provide the public and
responsible agencies with information about the potential environmental impacts associated with
implementation of the proposed Big Canyon Creek Restoration and Water Quality Improvement
Project. This IS/MND includes project-level analysis of the potential effects associated with the
project.
This IS/MND was prepared in compliance with Sections 15070 to 15075 of the California
Environmental Quality Act (CEQA) Guidelines of 1970 (as amended) and California Code of
Regulations, Title 14, Division, Chapter 3. In accordance with Section 15070, an MND shall be
prepared if the Initial Study identifies potentially significant effects, but revisions in the project
plans would avoid or mitigate the effects to a point where clearly no significant effects would
occur. As the CEQA lead agency, the City has determined that an IS/MND shall be prepared for
the proposed project.
Big Canyon Habitat Restoration and Water Quality Improvement Project 1-2 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
CHAPTER 2
Project Description
2.1 Introduction
The Big Canyon Restoration and Water Quality Improvement Project (proposed project) is
located on a 6-acre site in the eastern portion of the 60-acre Big Canyon Nature Park at the
downstream end of the Big Canyon Watershed in the City of Newport Beach (City), Orange
County, California (Figure 1). The Big Canyon Watershed covers approximately two square
miles located on the east side of Upper Newport Bay. Big Canyon Creek winds through the Big
Canyon Nature Park in a general southeast to northwest direction and then discharges into Upper
Newport Bay.
Big Canyon is the only natural, undeveloped portion of the Big Canyon watershed and the only
significant remaining natural canyon on the east side of Newport Bay. The upper 45-acre parcel is
owned by the City of Newport Beach. The lower 15-acre portion of the Nature Park is owned the
California Department of Fish and Wildlife and is a part of the Upper Newport Bay State
Ecological Reserve.
2.1.1 Project Background
The City has contemplated restoration efforts within Big Canyon for over a decade. Currently, the
City has funding for the restoration efforts that are part of Phases IA and IB (proposed project).
Potential future restoration efforts could also be proposed as a separate project, if future funding
is available. The proposed project is currently being planned in coordination with a Resource and
Recreation Management Plan (RRMP) being prepared by the Irvine Ranch Conservancy under
contract with the City of Newport Beach for the Big Canyon Nature Park. The RRMP provides a
framework for restoration and recreational improvements in the Nature Park that will be
consistent with the requirements of the Natural Community Conservation Plan/Habitat
Conservation Plan (NCCP) for the Central and Coastal sub-region of Orange County in the event
the City elects to incorporate the Nature Park into the NCCP. Potential future restoration efforts
within Big Canyon would also be coordinated with the RRMP.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-1 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
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Big Canyon Habitat Restoration and Water Quality Improvement Project. D130934Figure 1Regional Location Map
SOURCE: City of Newport Beach, ESRI
0 1.5
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Area ofDetail
Project Location
3. Environmental Checklist
The potential future restoration efforts could provide benefits to Big Canyon in addition to those
associated with the proposed project. These benefits could include water quality improvements in
Big Canyon Creek, restoration of natural creek channels impacted by hydromodification,
restoration of riparian and inland alkaline non-tidal marsh habitat, removal of non-native
vegetation and replacement with native plantings, remediation of selenium-laden sediment within
former freshwater ponds, creation of new transitional habitat to allow for future adaption of
coastal estuarine habitat due to sea-level rise, reduction of favorable mosquito breeding habitat,
and improvements and protection of public access within the natural areas of the Big Canyon
Nature Park, including coastal areas that will be subject to future inundation due to sea-level rise.
If funding is available, the City anticipates the preparation of a feasibility analysis to develop the
least impactful and most cost-effective approach to the freshwater ponds for the future restoration
efforts. These future efforts could include the protection of the biological resources within the
creek and downstream estuary by addressing the sediment and reeds within these ponds and
restoring the area of the future efforts. This potential future area currently contains invasive
pepper trees, and the City contemplates removal of them so that the area could be restored to a
transitional habitat to allow for adaptation of the coastal estuary due to sea-level rise. Based on
projected sea-level rise, this area of invasive pepper trees could be inundated in about 50 years.
Phases IA and IB, the current project, include the implementation of a creek and riparian habitat
restoration, habitat creation and enhancement, stormwater treatment wetland, dry-weather flow
diversions, culvert improvements, and trail planning in the upper portion of the Big Canyon
Nature Park. Implementation is scheduled for 2016–17.
2.1.2 Purpose and Need for Project
The Big Canyon Restoration Project – Phases IA and IB will: (1) restore historic riparian habitat
by removing non-native vegetation and replace it with native plantings, (2) stabilize the creek and
floodplain, (3) improve water quality in Big Canyon Creek and Newport Bay, and (4) enhance
public access within the Big Canyon Nature Park. Restoration and water quality improvements in
Phase I will proceed potential future restoration efforts in the remaining downstream areas of the
watershed.
2.1.2.1 Restore Historic Riparian Habitat
Big Canyon Creek has been documented as suitable for habitat restoration and enhancement due
to channel incision, loss of floodplain access, unstable banks, poor water quality, and more than
anything invasive species. Large portions of the riparian habitat are dominated by non-native
invasive species. This in turn has impacted the habitat quality of the riparian habitat in and along
Big Canyon Creek within the project area as well as in the downstream reaches of the Nature
Park.
2.1.2.2 Creek and Flood Plain Stabilization
Urbanization in the Big Canyon watershed has resulted in increased peak and sustained peak
storm flows that have resulted in hydraulic modification of the Big Canyon Creek within the
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-3 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
project limits. Downstream of the Jamboree Road culvert, Big Canyon Creek has responded to
hydromodification by incising into its historic channel bed and eroding channel banks in the
upper reach of the creek. Channel incision has reduced floodplain connectivity in the adjacent
riparian community that requires periodic inundation to support native biological species and
habitat conditions. Continued erosion and channel cutting will result in unstable embankments.
Flooding has also occurred historically at the site and has resulted in damage to Back Bay Drive.
Without the proposed creek and watershed restoration measures, the ongoing physical, chemical
and biological processes will result in additional bank and bed erosion, continued loss of riparian
habitat, reduced water quality in the creek and in Newport Bay, and loss of opportunities to
provide effective educational and recreational elements that serve the wider Orange County.
In addition a mosquito vector habitat is created when wet weather flows from Jamboree Road
discharge through a storm drain outfall to a scour pond in the creek’s riparian corridor. This
project addresses this mosquitos breeding habitat by eliminating the scour pond.
2.1.2.3 Water Quality Improvements
During wet weather, roadway-related pollutants (e.g., metals, sediment, oil and grease) enter Big
Canyon Creek from thoroughfares such as Jamboree Road and impact creek water quality. The
project includes measures to reduce metals and sediment loading into the creek and Bay from
stormwater flows from Jamboree Road. Big Canyon Creek is listed as an impaired waterbody for
selenium and a total maximum daily load (TMDL) has been established for the creek. The
receiving water for Big Canyon Creek is Newport Bay, which is listed as an impaired waterbody
for metals, toxics, nutrients, and bacteria. TMDLs have also been established to address these
impairments.
Big Canyon Creek, which drains the Big Canyon Watershed, is one of the few perennial streams
that discharge to Upper Newport Bay. Concentrations of selenium above water quality guidelines
have been measured in dry weather flows in Big Canyon Creek. The City has developed and is
implementing a selenium reduction program in the watershed that includes dry weather diversions
and other measures to reduce the selenium concentrations in the creek and into Upper Newport
Bay. This project includes additional measures to substantially reduce selenium loading in dry
weather flows as part of the selenium reduction program.
To address these issues, the proposed project would construct a bioretention cell water quality
treatment wetland that would treat wet weather flows and would also minimize the storm drain-
associated vector habitat in Big Canyon Creek. Additional water quality measures include the
construction of a dry weather flow diversion that re-routes flows of low selenium concentration
around identified sources of high selenium and return these better quality flows back into the
creek downstream. Seeps that are sources of high selenium will be passively collected and
diverted to the sanitary sewer.
Without the proposed water quality measures as part of Phase IA and IB of the Big Canyon
Restoration Project, impacts to water quality and biological beneficial uses will continue. The
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-4 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
success of the planned restoration efforts as part of this phase and potential future downstream
phases depends on addressing the existing water quality issues. These measures are needed for
the long-term sustainability of the restoration of Big Canyon.
2.1.2.4 Public Access Enhancements
Big Canyon Nature Park is used by residents and visitors for passive recreation. This is an
important destination for thousands of children participating in the Orange County Department of
Education Inside the Outdoors program. Inside the Outdoors provides watershed educational
activities for grade school children throughout the county including disadvantage communities.
As the largest undeveloped canyon adjacent to Newport Bay, it has the potential to become an
integral part of the Upper Newport Bay State Ecological Preserve and to provide unique
opportunities for the public to learn about the diversity of biological resources and environmental
protection within a short walking distance. At present, the upper portions of the Nature Park are
not attractive and rarely visited by the public. Along with habitat restoration, trail improvement
and information signage will provide an enhanced experience of the different ecotones in a
coastal watershed.
2.2 Project Location and Setting
The proposed project is located within the City of Newport Beach, on a 6-acre site in the eastern
portion of the 60-acre Big Canyon Nature Park. As shown in Figure 1, the project site is east of
Upper Newport Bay, west and east of Jamboree Road and includes Big Canyon Creek. Primary
regional access to the project site is provided by State Route 73, which runs north-south
approximately 2 miles north of the project site, and State Route 1, which runs north-south
approximately 1.25 miles south of the project site. Sub-regional access is provided via Jamboree
Road, Ford Road, and San Joaquin Hills Road. The project site is bounded by residential
developments on the bluffs to the north and south. Land uses within the project vicinity include
residential, recreational open space, golf courses, and commercial developments (Figure 2).
Located on the east side of Upper Newport Bay, Big Canyon Creek winds through the Big
Canyon Nature Park in a general southeast to northwest direction and then discharges into Upper
Newport Bay. The Big Canyon watershed is roughly 1,300 acres extending roughly 3 miles east
from Back Bay Drive into the San Joaquin Hills. Big Canyon is the only natural, undeveloped
portion of the Big Canyon watershed and the only significant remaining natural canyon on the
east side of Newport Bay. This 45-acre parcel contains native and non-native habitat and an array
of hiking trails, and is owned by the City of Newport Beach (Figure 3). Directly downstream of
the Project Area, the lower 15-acre portion of the Nature Park is owned by the California
Department of Fish and Wildlife (CDFW) and is a part of the Upper Newport Bay State
Ecological Reserve. Big Canyon Nature Park is located in the Upper Newport Bay State Marine
Conservation Area (SMCA) and is part of Southern California's coastal estuarine environment.
Newport Bay discharges adjacent to the Newport Coast Area of Special Biological Significance
(ASBS).
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-5 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
Big Canyon Habitat Restoration and Water Quality Improvement Project. D130934Figure 2Project Vicinity Map
SOURCE: USGS 7.5' Topo Quad Newport Beach, 1977
0 2,000
Feet
Project Boundary
Project Location
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JAMBOREE ROAD
Big Canyon Habitat Restoration and Water Quality Improvement Project. D130934Figure 3Project Aerial Map
SOURCE: City of Newport Beach, ESRI
Project Boundary
Parcel Boundary
Existing Sewer Features
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0 150
Feet
3. Environmental Checklist
The Project Area is characterized topographically by steeply sloping bluffs and a narrow,
moderately-sloped floodplain; slopes range in elevation from 20 to 75 feet above mean sea level
and the canyon creek ranges in elevation from below mean sea level to 25 feet above mean sea
level. A perennial stream identified as Big Canyon Creek is present within the Project Area and
supports degraded riparian habitat.
The Project Area supports six plant communities, as well as disturbed and developed areas
(Figure 4, Vegetation Communities). These plant communities include southern riparian forest,
freshwater march, alkali meadow, Diegan sage scrub, non-native grassland, and ornamental
habitat—of these, southern riparian forest, freshwater march, alkali meadow, and Diegan sage
scrub habitats are considered to be sensitive plant communities. Sensitive habitats are those
considered to support unique vegetation communities and/or special-status plant and/or wildlife
species, or function as corridors for wildlife movement.
The southern riparian forest habitat is heavily impacted by the invasion and establishment of
invasive trees and understory vegetation. A total of 194 species of invasive and non-native
grasses, forbs, and trees have been identified within the Big Canyon Nature Park (Dudek 2015).
The Big Canyon Project Area is bound on three sides by development. On the east side of
Jamboree, the Project Area is bound by the golf course to the east and south, and a condominium
complex to the north. On the west side of Jamboree Road, residential development is located at
the north and south side of the Project Area. To the west, the Big Canyon Nature Park extends to
Upper Newport Bay State Ecological Reserve.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-8 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
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abitat Restoration and Water Quality Improvement Project. D130934
Figure 4
Vegetation Communities Map
SOURCE: ESA, ESRI
Path: U:\GIS\GIS\Projects\13xxxx\D130934_BigCanyon\task\SupplementalPkg\Fig4_Vegetation.mxd, jyl 1/6/2016
0
150
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Project Boundary
Parcel Boundary
Vegetation Communities and Land Cover Types
AM, Alkali Meadow (0.10 acre)
CSS, Coastal Sage Scrub (1.53 acres)
DEV, Developed (0.04 acre)
DIST, Disturbed (Trail) (0.40 acre)
NNG, Non-native Grassland (2.83 acres)
ORN, Ornamental (0.78 acre)
SRF, Southern Riparian Forest (4.00 acres)
3. Environmental Checklist
2.3 Project Overview and Design
The proposed project has several objectives including:
• Restore and Enhance Riparian Habitat
• Improve Water Quality
• Reduce Flood/Erosion/Sedimentation Damage
• Encourage Public Participation and Provide Education
• Provide Recreational Opportunities
In order to meet these objectives, the proposed project includes the following elements:
• Creek Restoration and Riparian Habitat Creation & Enhancement – The project
proposes to conduct creek restoration activities that will include floodplain restoration,
streambank stabilization, and habitat restoration. Floodplain restoration and streambank
stabilization activities will result in increased flood flow attenuation, stabilization of the
north bank of the main channel, and creation of an active braided riparian floodplain. The
north creek bank at the inlet will be stabilized using natural bioengineering techniques.
Riparian habitat will be restored directly downstream of the floodplain restoration area
through the removal of invasive trees, soil modification to reduce plant-limiting sodium
levels, and replacement with native riparian species.
• Riparian Habitat Creation Activities – Riparian habitat creation activities will also be
conducted directly to the southwest of the proposed bioretention cell. This area will be
graded down to allow for riparian trees to access existing groundwater. Riparian habitat
enhancement will include removal of upstream and adjacent sources of Brazilian
peppertree both east of Jamboree Road and north of the creek.
• Stormwater Water Quality Treatment Bioretention Cell – The project includes the
construction of a water quality treatment bioretention cell that will treat wet-weather
flows from Jamboree Road and reduce the storm drain-associated vector habitat in Big
Canyon Creek. The basin will be vegetated with coastal sage scrub on the outer banks
and vegetated with native riparian forbs, grasses, and shrubs in the inner basin. These
species will have the ability to sequester toxins and tolerate flooded conditions for limited
periods of time. The basin will be periodically maintained per an approved Operation and
Maintenance Plan.
• Dry Weather Water Quality Selenium Reduction Measures – A dry weather flow
diversion that re-routes flows of lower selenium concentration around identified sources
of high selenium and return these better quality flows back into the creek will be
constructed as part of this project. Dry weather flows will be diverted from an
underground culvert on the east side of Jamboree Road and routed through an above
ground pipe along the south bank of the creek and through the storm drain culvert under
Jamboree Road. The pipe will discharge on the west side of Jamboree Road into the
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-10 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
floodplain that will be graded as part of this project. Seeps that are sources of high
selenium will be passively collected and diverted to the sanitary sewer.
• Infrastructure Improvements – The Project will also be constructed in coordination
with infrastructure improvements by the Orange County Sanitation District (OCSD). The
improvements are shown on Figure 3 and include the extension and improvement of the
existing access road along the toe of slope along the west side of Jamboree Road. The
access road improvements will be used access and maintain the sanitary sewer manhole
located to the north of the existing culvert outfall. The construction of the access road to
and over the existing culvert under Jamboree Road requires the extension of the culvert
as shown on Figure 3. A concrete stilling pool will be located at the end of the culvert
extension to dissipate hydraulic energy as the stormwater transitions from flow in the
culvert and discharges to the regraded floodplain. This stilling pool will be periodically
maintained to remove sediment and vegetation. Water from the stilling pool will exit via
a rip rap energy dissipater. OCSD will also install a permanent dosing station and access
area located to the south of the proposed habitat creation area.
• Community Access Improvements and Educational Opportunities – The extended
access road will provide an official trail where the public can learn about and enjoy the
native habitats. In addition, an 8-foot-wide bicycle path connector will be installed to
provide access directly from Jamboree Road. In addition, the maintenance road at the top
of the bioretention cell will also be used as a side viewing trail with interpretive signs
installed. Visitors using this trail will cross from the south to the north side of the creek
via the OCSD constructed turnaround area over the culvert, and follow a footpath on the
north side of the creek. The footpath on the north side of the creek will continue within
the coastal sage scrub habitat, following existing ad hoc trails that will be expanded to
approximately 42-inches wide. Trails allow for educational opportunities regarding water
quality and creek restoration activities, and through the installation of signage and as-
needed fencing, will keep the public out of sensitive habitats.
2.4 Project Components
As shown in Figure 5, the proposed project consists of habitat restoration, creation and
enhancement of riparian habitat, water quality improvements, and infrastructure and trail
improvements.
2.4.1 Creek Restoration, Creation and Riparian Habitat
Enhancement
This project consists of creek restoration and riparian habitat creation and enhancement activities
including stream bank stabilization, floodplain restoration, habitat creation, and restoration of
riparian habitat through invasive plant removal, soil remediation and revegetation.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-11 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
2.4.1.1 Floodplain Restoration & Streambank Stabilization
Directly downstream of the new culvert placement and stilling basin where Big Canyon Creek
flows into the Project Area, the project will create and restore the creek’s active floodplain
(Figure 6, Riparian Habitat Restoration Areas). The main channel is currently incised and is
confined to the incised narrow creek bed. The existing area to the south of the creek would be
lowered by approximately 6 feet to create a floodplain 2 to 3 feet above the low-flow channel to
allow for frequent inundation during high-flow events.
The 150 feet of channel and floodplain downstream of the stilling basin will be restored to
eliminate unstable eroding banks and a disconnected floodplain. A bankfull channel has been
sized using Dunne and Leopold’s (1978) regional hydraulic geometry for California creek
dimensions, cross-checked against the downstream stable section as a reference reach. For a
watershed of 1.7 square miles (as delineated using the USGS StreamStats web application), this
produces a bankfull width of 19 feet and a bankfull depth of 1.8 feet (rounded to 20 feet and
2 feet, respectively), very similar to the downstream channel width and depth in the more stable
area. For the restored reach, the existing channel invert elevation was retained. The channel will
be realigned away from the eroding and undercut north bank into the center of the floodplain, and
a new floodplain will be created on both banks. The floodplain and channel will be sized so that
flows exceeding the 2-year recurrence event start to inundate the floodplain.
On the south bank (river left, looking downstream) a 20-foot-wide floodplain will be created by
cutting into the existing over-steepened bank and upland terraces currently dominated by non-
native grasses as well as degraded riparian habitat. There will be a net reduction in fill within the
floodway, and an increase in both conveyance and frequently activated floodplain.
On the north bank (river right, looking downstream) the floodplain will be stabilized by adding
vegetated soil lifts. Encapsulated vegetated soil lifts planted with willows and other native
vegetation will be used to construct and protect the banks, and to provide erosion control. The
vegetated soil lifts will be constructed in 1-foot-thick lifts containing the native alluvial soil from
the site and amendments, with each lift encapsulated in coir fiber that will biodegrade over the
first 2–3 years, once the incorporated native riparian vegetation has established. Each lift will be
separated from the next by a layer of locally sourced native live willow stems that will grow
following installation.
For the cut banks (river left) willow brush mats will be placed over the cut bank and secured with
biodegradable coir fabric, then secured with biodegradable rope and wooden stakes. Both cut and
filled banks will be reinforced with biotechnical materials up to the 100-year water surface
elevation. This will serve to stabilize the grade and act as a planting medium for the growth of
riparian vegetation.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-12 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
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JAMBOREE ROAD
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Big Canyon Habitat Restoration and Water Quality Improvement Project. 130934
Figure 5
Project Components and Phasing
SOURCE: Burns & McDonnell; Dudek; ESA
Project Boundary
Parcel / APN #
Staging/Storage Area
New Grading Features
Existing Sewer Features
Water Line
Proposed Project Design
Proposed Trails
3.5-foot wide Trail
8-foot wide Trail
15-foot wide Trail
Surveyed Invasive Trees
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Brazilian pepper
Project Components
Phase 1A: Riparian Habitat Restoration
Riparian Habitat Restoration Area
Phase 1B: Mitigation Areas
Riparian Habitat Creation Area
Riparian Habitat Enhancement Area
Phase 1B: Facilities/Roadways
Access Road and Infrastructure Improvement
Bioretention Cell
Dosing Station
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ayer Credits: Source: Esri,
DigitalGlob
e, GeoEye, Earthstar Geographics,
CNES/Airbu
s DS, USDA, USGS, AEX,
Getmappin
g, Aerogrid, IGN, IGP, swisstopo,
and th
e G
IS User Community
Big Canyon H
abitat Restoration and Water Quality Improvement Project . D130934
Figure 6
Riparian Habitat Restoration Area
SOURCE: ESA, ESRI
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Pro
ject Boundary
Parcel Boundary
Existing Sewer Features
Rip
arian Habitat Restoration Area (2.03 acres)
0
150
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3. Environmental Checklist
2.4.1.2 Riparian Restoration & Soil Modification
Directly downstream of the floodplain restoration area, the riparian habitat will be restored to its
full functioning system (see Figure 6 and Figure 7, Habitat Mitigation Areas). Under current
conditions, invasive trees and an extensive understory of non-native forbs and grasses have been
documented. Bermuda grass (Cynodon dactylon), periwinkle (Vinca major), pampas grass
(Cortaderia selloana), and English ivy (Hedera helix) are just a few of the highly invasive
grasses and forbs found under the existing canopy. These invasives are better able to compete
under the high-saline soil conditions that are found within Big Canyon. Brazilian peppertree is the
most prevalent invasive tree species found in the canyon. The origins of this seed source can be
traced to two sources: (1) east of Jamboree Road, Brazilian peppertree has established on the
slopes of the Big Canyon drainage and adjacent upland area, with the seed source directly flowing
into the canyon; and (2) the west side of Jamboree Road directly to the north of the creek also has
this species growing on the slopes.
The trees, forbs, and grasses will be aggressively removed as part of this project. Mature trees
will be removed during mass grading and isolated individuals will be killed in place without soil
disturbance.
Soil testing results have indicated extremely high levels of sodium, boron, and sulfur in the soils.
Brazilian pepper tree’s high tolerance for these extreme levels of normally plant-inhibiting levels
indicates the reason this species is so successful in Big Canyon. Following invasive removal, the
soil will be amended to levels where native riparian vegetation can persist. The soil amendment
regiment will be incorporated directly into the top layers of soil following plant removal. Details
of the soil modifications will be included in the Habitat Restoration Plan prepared for this project.
Following soil modification, all areas will be actively planted, seeded, and maintained, with
topically applied soil treatments continuing through plant establishment, as prescribed.
2.4.1.3 Wetland/Riparian Habitat Creation
Additional riparian habitat will be created to the southwest of the proposed bioretention cell. This
will result in the expansion of contiguous riparian habitat, and will serve as part of the required
mitigation as replacement for some of the habitat lost as a result of implementation of other
components of this project (see Figure 7). This area has been previously disturbed and consists of
early successional forbs and grasses, providing low habitat value. Groundwater has been
measured in this area with a temporary piezometer at 5–7 feet below the existing ground surface.
The area will be graded to lower current ground elevations to access this permanent water source
to an elevation of approximately 39 feet mean sea level. A reduction of the elevation within the
creation area and in the existing riparian area to the west of the creek will bring the ground level
closer to the groundwater table, thereby allowing for establishment of riparian vegetation that will
be planted following grading and soil preparation activities. The discharge of the stormwater
treatment wetland will also be routed to this area to provide for periodic inundation during storm
events. The areas will also be subject to flooding during larger storm events, but will not pond
water or create a vector issue.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-16 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
Se
rvice L
ayer Credits: Source: Esri,
DigitalGlob
e, GeoEye, Earthstar Geographics,
CNES/Airbu
s DS, USDA, USGS, AEX,
Getmappin
g, Aerogrid, IGN, IGP, swisstopo,
and th
e G
IS User Community
Big Canyon Wetland Treatment and Creek Restoration Project . D130934
Figure 7
Habitat Mitigation Areas for Impacts to Jurisdictional Resources
SOURCE: ESA, ESRI
Path: U:\GIS\GIS\Projects\13xxxx\D130934_BigCanyon\task\SupplementalPkg\Fig7_HabitatMitigationAreas_JD.mxd, jyl 1/7/2016
Project Boundary
Parcel Boundary
Existing Sewer Features
Habitat Mitigation Areas for Impacts to Jurisdictional Resources
Riparian Habitat Creation Area (0.25 acre)
Riparian Habitat Enhancement Area (1.07 acres)
0
150
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3. Environmental Checklist
2.4.2 Water Quality Improvements
The project includes measures to treat storm flows and dry-weather flows that will result in
improved water quality for habitat and wildlife in Big Canyon.
2.4.2.1 Stormwater Treatment System (Primary Stormwater
Treatment Structure, Bioretention Cell)
The purpose of the stormwater treatment system is to reduce transportation-related constituent
concentrations currently discharged to Big Canyon Creek during storm events and to attenuate
stormwater peak-flow discharge rates from the contributing Jamboree Road drainage area.
The transportation-related pollutants are currently conveyed to the receiving waters in Big
Canyon Creek from a variety of sources, including vehicles, road maintenance, maintenance
facility runoff, and landscaping maintenance. Vehicles are known to produce a variety of
pollutants that can have a negative impact on water quality in the receiving waters to which they
drain.
Metals such as copper and zinc can build up on road surfaces through brake and tire wear; other
metals such as cadmium, chromium and sometimes lead can be deposited on road surfaces from
paint on vehicles and streets. Metals often bind to sediments, trash, and debris on road surfaces;
these can be carried into waterways during storm events. In addition to pollutants associated with
vehicles, landscaped areas associated with or adjacent to streets (e.g., median, parkway, and
residential landscaping) can be sources of pollutants such as pesticides, nutrients (particularly
nitrate and phosphorus), and fecal-indicator bacteria (all of which are known to be associated
with urban landscaping, which is found throughout the 11.1-acre Jamboree Road drainage area).
These pollutants can be transported to receiving waters during storm events. Finally, in addition
to direct deposition to the road surface, street surfaces and adjacent walkways and landscaped
areas can be impacted from vehicle emissions through atmospheric deposition of pollutants such
as the dissolved fraction of metals and organics (e.g., polynuclear aromatic hydrocarbons (PAHs).
According to national and regional best management practices (BMPs) manuals (e.g., the
California Stormwater Quality Association BMP handbook), the technology proposed in the
stormwater treatment system has been shown to be effective in treating a variety of pollutants
associated with transportation runoff, including trash, sediment (and attached pollutants),
nutrients and organics such as PAHs and pesticides, and fecal-indicator bacteria. The stormwater
treatment system would consist of a primary stormwater treatment structure and a bioretention
cell, as described below.
Primary Stormwater Treatment Structure
A primary treatment structure would be constructed to receive runoff from existing stormwater
inlets serving Jamboree Road. The contributing drainage area draining to the primary stormwater
treatment structure is approximately 11.1 acres. The purpose of this structure is to trap, contain,
and pretreat trash, total suspended solids (TSS), and free oils prior to conveyance to the
bioretention cell. Located adjacent to Jamboree Road, the primary stormwater treatment structure
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-18 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
would be approximately 40 square feet in size and include three chambers. The first chamber
would be designed to collect dense solids and trash (floatables); the second would collect
sediment and finer solids; and the third would provide storage and delivery of dissolved phase
constituents to the bioretention cell. Manhole access ports would be installed for periodic removal
of trash and sediment from the three chambers.
Bioretention Cell
The bioretention cell is an underground, modified constructed wetland that would be designed
specifically to treat the suite of transportation-related pollutants found in urban watersheds. The
bioretention cell would be constructed to treat stormwater flows that discharge from the primary
stormwater treatment structure. The surface area of the bioretention cell would be approximately
0.47 acres in size when measured at the top of the bioretention cell berm (see Figure 5). The
bioretention cell would be designed to capture and treat the stormwater that discharges from
Jamboree Road. It will treat approximately 0.75 inches of stormwater in a 24-hour period. The
bioretention cell will attenuate and reduce the peak discharge rate to Big Canyon Creek during
storm events.
The bioretention cell will consist of (from top to bottom) layers of soil, sand, and gravel,
underlain by an impermeable liner. The top of the cell will be planted with native vegetation. The
soil layer would be approximately 2 to 3 feet thick and would be underlain by a 6-inch sand filter
bed located between the bioretention soil and drainage gravel layer situated in the bottom of the
bioretention cell. The bottom 12-inch gravel drainage layer will form the base layer of the
bioretention cell and will be underlain by a geotextile cushion. The entire bioretention cell will be
underlain by a 60-MIL high-density polyethylene (HDPE) liner.
The bioretention cell would be divided into two subcells, hydraulically separated from one another
by an impermeable barrier, to enable the comparison of water quality effluent between the cells.
One subcell would be designed to be free draining and the second subcell would be designed such
that approximately 12 inches of treated water would remain on the liner and within the gravel
drainage layer.
Stormwater will flow via gravity from the primary stormwater treatment structure to the top of
the subcells through a series of perforated and solid inflow PVC pipes. Pollutants would be
removed from stormwater as it flows down through the treatment media. Treated water would
flow from the bottom of the bioretention cell through a series of PVC pipes into a newly created
wetland habitat area located to the south of the bioretention cell (see Figure 5). The wetland
habitat area will be graded to allow for infiltration to groundwater and for surface flow return to
Big Canyon Creek.
Table 2-1 summarizes the anticipated pollutant reductions from stormwater (wet weather)
anticipated from the primary stormwater treatment structure and bioretention cell.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-19 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
TABLE 2-1
ANTICIPATED REDUCTION OF POLLUTANTS FROM STORMWATER
(WET WEATHER) BY THE PROPOSED BIORETENTION CELL
Pollutant of Concern Estimated Percent
Reduction
Total Suspended Solids1 80%
Zinc1 69%
Copper1 44%
Lead1 52%
Cadmium2 52%
Fecal Coliform2 75%
Nitrate1 35%
Total Phosphorus1 55%
1 National Pollutant Removal Performance Database, 2000 2 Structural BMP Specifications from the Massachusetts Stormwater Handbook, 2010 for
constructed wetlands and infiltration basin.
The interior of the bioretention cell will be periodically maintained, per the approved Operation
and Maintenance Plan. This may include the cleanout of vegetation or replacement of soil to
ensure continued water quality improvement.
2.4.2.2 Selenium Reduction Measures in Dry Weather Flows (Dry
Weather and Seeps / Collection and Diversions)
Dry Weather Flow Diversion
The purpose of the dry weather flow diversion is to limit the contact between dry weather flows
with low selenium concentrations with groundwater seepage flows that contain much higher
selenium concentrations. Monitoring investigations conducted by the City in 2015 determined
that seepage flows with high selenium concentrations occur in the creek on the east side of
Jamboree Road between the proposed diversion and the entrance to the existing culvert. High
selenium seeps also occur on the west side of Jamboree Road just downstream of the mouth of
the existing culvert (City of Newport Beach 2015, unpublished data). The proposed project
proposes to passively collect these high selenium concentration seeps and direct them to the
sanitary sewer. The estimated seepage flows are anticipated to be less than 10% of the total
current dry weather flows in Big Canyon Creek. Therefore, approximately 90% of the current dry
weather flows will be returned to the creek. Diverting the high selenium seepage flows will
substantially reduce in-stream selenium concentrations in the downstream creek flowing through
the restoration area. No significant impact is expected to the riparian habitat within the section of
the creek between the diversion and the returned cleaner dry weather flows as groundwater
seepage will sustain the willow vegetation and planned invasive removal and revegetation will
further enhance this section of the creek to the east of the culvert under Jamboree Road.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-20 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
Dry weather flows with lower selenium concentrations will be diverted in a new diversion
structure located on the Big Canyon Golf Course. The diversion structure will divert about 0.5 cfs
and allow higher flows to pass through the diversion structure. The diversion flow line will
include a valve that will enable the diverted flows to be reduced and adjusted if necessary. The
diversion line will flow via gravity and will be installed along the existing southern slope of the
ditch north of the golf course maintenance yard. No grading and soil disturbance is anticipated.
The diversion line will be at grade on the surface of the slope and will be anchored to the slope
using an anchorage system. The anchor system will be installed along the existing disturbed top
of slope adjacent to the golf course maintenance yard fence. The diversion line will transition
from the slope into the east side of the Jamboree Road existing culvert. The diversion line will be
installed inside the existing Jamboree Road culvert and inside the new culvert extension. The
diversion line will discharge dry weather flows into the restored floodplain as shown in Figure 5,
to provide surface water to that area.
Numerous studies and assessments on selenium loads and sources in Big Canyon Creek have
been conducted. Reeder (2011) provided a comprehensive assessment of the geology, hydrology,
and water quality related to selenium sources in the watershed from studies conducted as early as
the 1970s through 2011. Since then, additional studies have been conducted in the watershed on
flow rates (Weston 2013), water balance in the upper watershed (DBS&A 2015), and specific
selenium source identification assessments in the lower portion of the watershed (City of
Newport Beach, unpublished data). Based on long-term monitoring conducted in 2012 (Weston
2013), the approximate base dry weather flow rate of Big Canyon Creek at Jamboree Road is
0.420 cfs. The proposed dry weather flow diversion upstream of Jamboree Road is not anticipated
to impact the natural creek function. It will divert low selenium water around a stream reach of
approximately 170 feet just upstream of Jamboree Road (Figure 5) where high selenium
groundwater seeps have been identified (City of Newport Beach, unpublished data). Groundwater
originating in this reach is estimated to contribute less than ten percent of the dry weather
baseline flow in the creek, which will be diverted to sanitary sewer. The wet weather function of
the creek will not be affected by the dry weather flow diversion.
To support the design of the culvert extension and stilling basin, wet weather design discharge
rates were determined. The Big Canyon Watershed drains approximately 1,062 acres. The
modeled 100-year flow rate is approximately 2,510 cfs. The 10-year flow rate is 1,680 cfs and the
2-year flow rate 1,260 cfs.
The diversion line may be extended to the bio-infiltration cell (if slopes allow) to enable irrigation
of native vegetation on the surface of the bioretention cell during the plant establishment period
and for persistence of the vegetation.
Seep Water Flow Collection and Diversion
Seeps containing high concentrations of selenium have been observed along the north and south
banks along a 170-foot reach of the creek on the east side of Jamboree Road near the existing
culvert (City of Newport Beach, unpublished data). The seep flows will drain through the existing
culvert and the new culvert extension and collect in a low point in the bottom the stilling basin
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-21 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
floor. As the seep water collects and pools, it will then spill over into vertical open topped risers
or similar system and drain into the OCSD sewer. The design will enable sediment to settle out
and collect in the stilling basin floor while allowing the seep water to discharge to the sewer. The
seep water diversion system will be designed such that the system can be shut off prior to
precipitation events. The seep water diversion system will be designed such that the pooled water
in the stilling basin floor is limited in extent to minimize mosquito vector habitat.
Seepage containing high concentrations of selenium is also indicated based on water quality
results, immediately downstream of the existing culvert on the west side of Jamboree Road. In
order to address this source of high selenium in this area that corresponds to the new culvert
extension and stilling pool, seeps will be passively collected and diverted via gravity to the OCSD
sewer. Seepage that would otherwise discharge into the creek will be intercepted and collected
from the gravel layer that forms the bedding material for the new concrete box culvert extension
and the bedding material for the bottom of the concrete stilling basin. Perforated HDPE collection
pipes will be installed in the gravel bedding material to convey water to a flow metering structure
prior to discharge to the OCSD sanitary sewer. The seepage flow into the sewer is anticipated to
be intermittent and the flow is rate anticipated to be low (in the 0-10 gpm range) due to the
relatively low permeability of the soil in this area. The seepage collection lines include a valve to
enable the collected flow to the OCSD sanitary sewer to be controlled. If the flow rate is higher
than anticipated, the flow will likely be reduced through coordination with OCSD.
2.4.3 Infrastructure Improvements
2.4.3.1 Orange County Sanitation District Access Road and Dosing
Facility
The Project will also be constructed in coordination with infrastructure improvements requested
by the Orange County Sanitation District (OCSD) that include the extension and improvement of
the existing access road along the toe of slope along the west side of Jamboree Road and the
construction a dosing station for odor control.
A 12-foot wide gravel roadway would be constructed to facilitate access to three OCSD manholes
including a manhole located to the north of the existing culvert outfall. To provide access to this
manhole, the existing culvert beneath Jamboree Road will be extended approximately 75 feet and
an access roadway will be constructed on top of the culvert. The new gravel road would parallel
Jamboree Road and connect to the existing gravel access road on the south end of the site. The
gravel access road will also serve as pedestrian trail which is consistent with existing gravel roads
in Big Canyon to serve the dual purpose of manhole access and pedestrian trails.
The culvert extension will include a concrete stilling basin at the end of the culvert extension. The
purpose of the stilling basin is to dissipate hydraulic energy during wet weather storm flow
events. The stilling basin will be constructed with reinforced concrete and will include a concrete
access ramp to enable access for maintenance. Maintenance activities will include sediment and
debris removal from the stilling basin during dry weather.
Big Canyon Habitat Restoration and Water Quality Improvement Project 2-22 ESA / Project No. 130934
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An automatic chemical-dosing station would be constructed near the beginning of the access road
extension. The dosing station consists of a 12-foot high tower, 8-foot diameter that would be
constructed on a 20-foot by 20-foot pad, and a gravel access road as needed to access the station.
Native plants will be planted around the facility. The station would be maintained on a monthly
basis.
A vehicle access path that doubles as the hiking trail would be constructed as a part of the
proposed project to provide maintenance access to the infrastructure improvement components.
2.4.3.2 Community Access Improvements and Educational
Opportunities
Public access to the project site and surrounding environs is currently provided by existing hiking
paths in Big Canyon Nature Park. The project includes providing improved and new trails for
public access both on the north and south side of the creek. This new trail will allow for
educational opportunities regarding water quality and creek restoration activities while keeping
trails out of sensitive habitats and restored and enhanced riparian corridors.
Preliminary public access and walkway signage and locations has been developed from previous
efforts and will be incorporated in this project. The proposed OCSD access road will serve to
connect the existing gravel path over the creek to connect with an improved trail on the north side
of the creek. In addition, a bicycle path connector has been incorporated into this design to allow
for direct access from Jamboree Road. Interpretive elements include key features such as a
viewing area on the bio retention cell maintenance road, and informational signage. This plan is
consistent with on-going efforts planned for the Big Canyon Watershed in consultation with the
City, environmental organizations including the Newport Bay Conservancy and Irvine Ranch
Conservancy, and the appropriate regulatory agencies.
2.5 Construction Activities and Schedule
Project construction is expected to begin in Fall 2016 and will include the infrastructure
components of the project, habitat restoration, and habitat mitigation implementation.
Construction will be complete by March 31, 2017 to avoid impacts during the nesting season.
Planting of all restoration and mitigation areas will take place once grading has been completed
(see Table 2-2).
Construction activities would commence with the installation of construction stormwater
pollution prevention BMPs in accordance with the project Stormwater Pollution Prevention Plan
(SWPPP). Following the installation of stormwater BMPs, project construction work would occur
in phases for a duration of five to six months. The following schedule presents the construction
phases, the activities to be completed under each phase, and the duration of the activities. Several
activities will run concurrently to achieve the overall construction schedule of approximately five
months.
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Phase Activity Duration Month 1 Month 2 Month 3 Month 4 Month 5
Mobilization &
Earthwork
Site preparation
clearing & grubbing
1-2 weeks
Excavation and
grading
2-3 weeks
Drainage
Structures and
Piping
Construction
Culvert extension 4-6 weeks
Dry weather diversion
structures and external
piping
2-3 weeks
Water Quality
System
Construction
Bioretention cell liner
and piping
1-2 weeks
Bioretention cell media
placement
1-2 weeks
Bioengineering
structure construction
1-2 weeks
OCSD Scope OCSD dosing station
installation
4-6 weeks
Restoration Site vegetation
restoration
3-4 weeks
Approximately 5 acres would be disturbed during project construction. Earthwork cuts are
anticipated from the widened floodplain downstream and from the south bank of the Big Canyon
Creek and the wetland habitat area. The total earthwork cut volume is approximately 4,000 cubic
yards. Earthwork fills are anticipated for the bioretention cell berms and OCSD access road. The
anticipated fill volume for mass earthwork is approximately 8,000 cubic yards. The net total
volume import (soil and bioretention cell media) is approximately 4,000 cubic yards.
Haul trucks would be used to transport earthen material used to construct the project. These haul
trucks would access the site from the intersection of San Joaquin Road and Jamboree Road west
on San Joaquin Road to Back Bay Drive, and then travel north on Back Bay Drive to the Big
Canyon Trail maintenance road entrance. Trucks would follow the maintenance road east to the
construction staging area as shown in Figure 5. It is estimated that approximately 40 daily haul
truck trips and up to 900 to 1,000 total haul truck trips for material deliveries would occur over
the course of construction.
Approximately eight employees would be present on the project site at any given time during
construction, including a construction superintendent, up to two laborers, up to three equipment
operators, and up to two haul truck drivers. Typical equipment required for construction of the
project would include a loader, back hoe, dozer, compactor, chipper (mulch), haul trucks, and a
water truck. Construction is expected to occur between the hours of 7:00 a.m. and 6:30 p.m.
Monday through Friday and 8:00 a.m. and 6:00 p.m. on Saturdays as set forth in the City of
Newport Beach’s Municipal Code 10.28.040, Construction Activity – Noise Regulations. No
construction would occur on Sundays or federal holidays.
Construction activities will be coordinated with erosion control and surface water diversion to
prevent soils loss, channel instability, discontinuity of water supply during dry weather season,
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3. Environmental Checklist
and flood damages during major wet season events. A Water Quality Management Plan (WQMP)
will be developed as part of the Construction SWPPP to be implemented from the onset of the
construction to post construction.
Biologically sensitive area protection will be established prior to construction and periodically
monitored. Water quality protection during construction will be monitored based on a pre-
construction Quality Assurance Project Plan (QAPP) and Sampling and Analysis Plan (SAP), to
be developed prior to construction.
TABLE 2-2
PRELIMINARY CONSTRUCTION DURATION
Construction Activity Approximate Duration
Site preparation clearing & grubbing 1-2 weeks
Excavation and grading 2-3 weeks
Culvert extension 4-6 weeks
Dry weather diversion structures & external piping 2-3 weeks
Bioretention cell liner & piping 1-2 weeks
Bioretention cell media placement 1-2 weeks
Bioengineering structure construction 1-2 weeks
OCSD dosing station installation 4-6 weeks
Site vegetation restoration 3-4 weeks
Total Construction Duration Per Component
SOURCE: B&M
2.6 Project Operation and Maintenance
Within the bioretention cell, sediment removal is expected only after major rainfall events.
Maintenance is critical if stormwater wetland basins are to function as originally designed. A
specific maintenance plan will be developed for the bioretention cell when the final design has
been completed, outlining the schedule and scope of maintenance operations, as well as the
documentation and reporting requirements. The following are general maintenance requirements:
1. The stormwater wetland basin should be inspected annually and inspections after major
storm events are encouraged (wetland basin inspection and maintenance checklists will
be developed specifically for the bioretention cell). Trash and debris should be removed
as needed, but at least annually prior to the beginning of the wet season.
2. Site vegetation should be maintained as frequently as necessary to maintain the aesthetic
appearance of the site and to prevent clogging of outlets, creation of dead volumes, and
barriers to mosquito fish to access pooled areas, and as follows:
• Vegetation, large shrubs, or trees that limit access or interfere with basin operation
should be pruned or removed.
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• Slope areas that have become bare should be revegetated and eroded areas should be
regraded prior to being revegetated.
• Invasive vegetation, such as Alligatorweed (Alternanthera philoxeroides), Halogeton
(Halogeton glomeratus), Spotted Knapweed (Centaurea maculosa), Giant Reed
(Arundo donax), Castor Bean (Ricinus communis), Perennial Pepperweed (Lepidium
latifolium), and Yellow Starthistle (Centaurea solstitalis) must be removed and
replaced with noninvasive species. Invasive species should never contribute more
than 25% of the vegetated area.
• Dead vegetation should be removed if it exceeds 10% of area coverage. This does not
include seasonal die-back where roots would grow back later in colder areas.
Vegetation should be replaced immediately to maintain cover density and control
erosion where soils are exposed.
3. Sediment buildup exceeding 6 inches over the storage capacity in the first cell should be
removed. Sediments should be tested for toxic substance accumulation in compliance
with current disposal requirements visual or olfactory indications of pollution are noticed.
If toxic substances are encountered at concentrations exceeding thresholds of Title 22,
Section 66261 of the California Code of Regulations, the sediment must be disposed of in
a hazardous waste landfill.
4. Following sediment removal activities, replanting and/or reseeding of vegetation may be
required for reestablishment.
Routine maintenance will be performed to keep the bioretention cell piping, diversion piping, and
seep water inlets clear of debris and sediments. Erosion control materials for embankment and
slope protection will be inspected routinely and repaired or replaced, as necessary. Routine
maintenance of the diversion structures and stilling pool will be required on a regular basis to
keep them clear of sediment and debris accumulations.
Upon initial installation, maintenance could occur as frequently as once per month, and could
include a visual check, debris clearing, and/or equipment repair. Semiannual inspections for
beginning and end of the wet season will be scheduled to identify any erosion problems and
remove debris and sediment accumulation. A large rain event may require additional visual
inspections to clear debris. The additional visual inspections may also require evaluation of
wetland vegetation and inspection of vector presence or habitats on the project site. Inspections
will include water quality BMPs at the storm outlets for erosion protection. Additionally, BMPs
involving filtration functions will be inspected to ensure their pollutant reduction efficiency.
Operation of the bioretention cell would be passive for the most part, requiring occasional
inspections to confirm the treatment cells are operating as intended by the design. As a part of the
proposed project, a comprehensive Operations and Maintenance Plan has be developed (see
Appendix A). The Plan will be updated when the final design for the bioretention cell is
complete.
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2.7 Project Approvals and Discretionary Actions
The City of Newport Beach would use this IS/MND and supporting documentation in its decision
to certify this IS/MND and approve the project. Regulatory Agencies would similarly use this
IS/MND and supporting documentation to support additional discretionary actions, including as:
• City of Newport Beach: Grading Permit
• City of Newport Beach: Right of Entry Permit
• U.S. Army Corps of Engineers (USACE): 404 Certification
• California Department of Fish and Wildlife (CDFW): Streambed Alteration Agreement
• California Coastal Commission: Coastal Development Permit
• Regional Water Quality Control Board: 401 Certification
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CHAPTER 3
Initial Study Environmental Checklist
1. Project Title: Big Canyon Habitat Restoration and Water
Quality Improvement Project
2. Lead Agency Name and Address: City of Newport Beach
100 Civic Center Drive
Newport Beach, CA 92660
3. Contact Person and Phone Number: Bob Stein
(949) 644-3322
4. Project Location: City of Newport Beach, Orange County, CA
5. Project Sponsor’s Name and Address: City of Newport Beach
100 Civic Center Drive
Newport Beach, CA 92660
6. General Plan Designation(s): Open Space (City of Newport Beach)
7. Zoning Designation(s): Open Space (City of Newport Beach)
7. Description of Project: See Chapter 2, Project Description
9. Surrounding Land Uses and Setting: Recreation; Residential
10. Other public agencies whose
approval is required:
Army Corps of Engineers;
Regional Water Quality Control Board;
California Department of Fish and Wildlife;
Coastal Commission
11. Discretionary Actions: City of Newport Beach: Grading Permit
City of Newport Beach: Right of Entry Permit
U.S. Army Corps of Engineers (USACE): 404
Permit
California Department of Fish and Wildlife
(CDFW): Streambed Alteration Agreement
California Coastal Commission: Coastal
Development Permit
Regional Water Quality Control Board: 401
Certification
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3. Environmental Checklist
Environmental Factors Potentially Affected
The proposed project could potentially affect the environmental factor(s) checked below. The
following pages present a more detailed checklist and discussion of each environmental factor.
Aesthetics Agriculture and Forestry Resources Air Quality
Biological Resources Cultural Resources Geology, Soils and Seismicity
Greenhouse Gas Emissions Hazards and Hazardous Materials Hydrology and Water Quality
Land Use and Land Use Planning Mineral Resources Noise
Population and Housing Public Services Recreation
Transportation and Traffic Utilities and Service Systems Mandatory Findings of Significance
Note: None of the environmental factors were checked above because the proposed project would
not result in a potentially significant impact on any of the environmental factors after the
implementation of mitigation measures.
DETERMINATION: (To be completed by Lead Agency)
On the basis of this initial study:
I find that the proposed project COULD NOT have a significant effect on the environment,
and a NEGATIVE DECLARATION would be prepared.
I find that although the proposed project could have a significant effect on the
environment, there will not be a significant effect in this case because revisions in the
project have been made by or agreed to by the project proponent. A MITIGATED
NEGATIVE DECLARATION will be prepared.
I find that the proposed project MAY have a significant effect on the environment, and an
ENVIRONMENTAL IMPACT REPORT is required.
I find that the proposed project MAY have a “potentially significant impact” or
“potentially significant unless mitigated” impact on the environment, but at least one effect
1) has been adequately analyzed in an earlier document pursuant to applicable legal
standards, and 2) has been addressed by mitigation measures based on the earlier analysis
as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required,
but it must analyze only the effects that remain to be addressed.
I find that although the proposed project could have a significant effect on the
environment, because all potentially significant effects (a) have been analyzed adequately
in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards, and
(b) have been avoided or mitigated pursuant to that earlier EIR or NEGATIVE
DECLARATION, including revisions or mitigation measures that are imposed upon the
proposed project, no further environmental documentation is required.
Signature Date
Printed Name For
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3. Environmental Checklist
Environmental Checklist
3.1 Aesthetics
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
1. AESTHETICS — Would the project:
a) Have a substantial adverse effect on a scenic vista?
b) Substantially damage scenic resources, including,
but not limited to, trees, rock outcroppings, and
historic buildings within a state scenic highway?
c) Substantially degrade the existing visual character or
quality of the site and its surroundings?
d) Create a new source of substantial light or glare
which would adversely affect daytime or nighttime
views in the area?
Discussion
a) Have a substantial adverse effect on a scenic vista?
No Impact. A scenic vista is defined as a viewpoint that provides expansive views of a highly
valued landscape for the benefit of the general public. According to the City of Newport Beach
General Plan Update EIR, the City does not contain any officially designated scenic vistas;
however, public view points are identified within the City. The nearest public view point is
located about 1,200 feet west of the project site within the western portion of Big Canyon Park.
This public view point provides views of Upper Newport Bay.
Project grading and construction activities as well as restoration activities on the project site
would not affect views from the nearest public view point because the view point offers views to
the west toward Upper Newport Bay, and the project site is located east of the view point.
Therefore, implementation of the proposed project would result in no impacts on scenic vistas.
b) Substantially damage scenic resources, including, but not limited to, trees, rock
outcroppings, and historic building within a state scenic highway?
No Impact. There are no officially designated scenic highways within Newport Beach (City of
Newport Beach 2006). However, the project area is approximately one mile north of State Route
1 (Pacific Coast Highway), identified by the City as “Eligible for State Scenic Highway”
designation. Because no scenic highways are currently designated within the City,
implementation of the proposed project would result in no impact to scenic resources within a
state- or locally designated scenic highway.
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c) Substantially degrade the existing visual character or quality of the site and its
surroundings?
Less than Significant Impact. The construction activities associated with the project would
result in changes to the existing visual character of the project site, including construction grading
and the removal of existing vegetation. However, as mentioned above, the creek restoration and
riparian habitat enhancement component of the project would remove the non-native vegetation
and restore native vegetation on the project site. This component of the project would improve the
existing visual character and quality of the site by restoring natural habitat conditions in the creek,
and thus would result in a less than significant impact to the existing visual quality of the project
site.
d) Create a new source of substantial light or glare which would adversely affect day
or nighttime views in the area?
No Impact. The proposed project would create no new source of lighting in the project area, and
thus would result in no light impacts. The project includes structural improvements to the culvert
and stilling pond, however these features would use earth materials in their construction, and
would result in no glare impacts. Thus, the project would result in no adverse effects to day or
nighttime views in the area due to light or glare.
Resources
City of Newport Beach. Draft Environmental Impact Report: General Plan 2006 Update.
Volume I. Section 4.1: Aesthetics and Visual Quality. April 2006.
California Department of Transportation. Scenic Highway Routes – Orange County.
http://www.dot.ca.gov/hq/LandArch/16_livability/scenic_highways/index.htm. Accessed
January 14, 2016.
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3. Environmental Checklist
3.2 Agricultural and Forest Resources
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
2. AGRICULTURAL AND FOREST RESOURCES —
In determining whether impacts to agricultural resources are significant environmental effects, lead agencies may refer to
the California Agricultural Land Evaluation and Site Assessment Model (1997) prepared by the California Department of
Conservation as an optional model to use in assessing impacts on agriculture and farmland. In determining whether
impacts to forest resources, including timberland, are significant environmental effects, lead agencies may refer to
information compiled by the California Department of Forestry and Fire Protection regarding the state’s inventory of forest
land, including the Forest and Range Assessment Project and the Forest Legacy Assessment project; and forest carbon
measurement methodology provided in Forest Protocols adopted by the California Air Resources Board.
Would the project:
a) Convert Prime Farmland, Unique Farmland, or
Farmland of Statewide Importance (Farmland), as
shown on the maps prepared pursuant to the
Farmland Mapping and Monitoring Program of the
California Resources Agency, to non-agricultural
use?
b) Conflict with existing zoning for agricultural use, or a
Williamson Act contract?
c) Conflict with existing zoning for, or cause rezoning
of, forest land (as defined in Public Resources Code
section 12220(g)), timberland (as defined by Public
Resources Code section 4526), or timberland zoned
Timberland Production (as defined by Government
Code section 51104(g))?
d) Result in the loss of forest land or conversion of
forest land to non-forest use?
e) Involve other changes in the existing environment
which, due to their location or nature, could result in
conversion of Farmland to non-agricultural use or
conversion of forest land to non-forest use?
Discussion
In determining whether impacts to agricultural resources are significant environmental effects,
lead agencies may refer to the California Agricultural Land Evaluation and Site Assessment
Model (1997) prepared by the California Dept. of Conservation as an optional model to use in
assessing impacts on agriculture and farmland. In determining whether impacts to forest
resources, including timberland, are significant environmental effects, lead agencies may refer to
information compiled by the California Department of Forestry and Fire Protection regarding the
state’s inventory of forest land, including the Forest and Range Assessment Project and the Forest
Legacy Assessment project; and forest carbon measurement methodology provided in Forest
Protocols adopted by the California Air Resources Board.
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a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance
(Farmland), as shown on the maps prepared pursuant to the Farmland Mapping
and Monitoring Program of the California Resources Agency, to non-agricultural
use?
No Impact. The project vicinity is located in a developed and urbanized area of the city. The
project site is located on land designated as Urban and Built-Up Land, as shown on maps
prepared pursuant to the Farmland Mapping and Monitoring Program (Department of
Conservation 2012). Because the project site does not contain Farmland, the proposed project
would not cause direct or indirect impacts related to the conversion of Prime Farmland, Unique
Farmland, or Farmland of Statewide Importance. Thus, the project would result in no Farmland
conversion impacts.
b) Conflict with existing zoning for agricultural use, or a Williamson Act contract?
No Impact. A Williamson Act Contract requires private landowners to voluntarily restrict their
land to agricultural land and compatible open-space uses. There is no Williamson Act contract in
effect for the project site nor does the City have any agriculture-oriented zoning designations or
Williamson Act Contract land. Because the project site does not have a Williamson Contract, the
project would result in no zoning conflict or Williamson Act contract impacts.
c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in
Public Resources Code section 12220(g)), timberland (as defined by Public
Resources Code section 4526), or timberland zoned Timberland Production (as
defined by Government Code section 51104(g))?
No Impact. The project site is zoned as Open Space and is surrounded by lands zoned for
residential and industrial uses. The City of Newport Beach does not contain any land zoned as
forest land, timberland, or for timberland production. Therefore, the project would result in no
forest land or timberland zoning impacts.
d) Result in the loss of forest land or conversion of forest land to non-forest use?
No Impact. The project site and surrounding area contain no forest land. Thus, implementation of
the proposed project would result in no impacts related to the loss or conversion of forest land to
non-forest use.
e) Involve other changes in the existing environment which, due to their location or
nature, could result in conversion of Farmland, to non-agricultural use or
conversion of forest land to non-forest use?
No Impact. There are no agricultural uses or forest uses in the vicinity of the project site.
Therefore, the proposed project would not involve changes in the existing environment that could
result in conversion of Farmland to non-agricultural use or conversion of forest land to non-forest
use.
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Resources
California Department of Conservation: Farmland Mapping and Monitoring Program. Orange
County Important Farmland 2012. January 2015.
City of Newport Beach. Newport Beach Municipal Code. Title 20: Planning and Zoning. Passed
November 24, 2015. <http://www.codepublishing.com/CA/NewportBeach/
?NewportBeach20/NewportBeach20.html>. Accessed January 14, 2015.
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3. Environmental Checklist
3.3 Air Quality
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
3. AIR QUALITY —
Where available, the significance criteria established by the applicable air quality management or air pollution control
district may be relied upon to make the following determinations.
Would the project:
a) Conflict with or obstruct implementation of the
applicable air quality plan?
b) Violate any air quality standard or contribute
substantially to an existing or projected air quality
violation?
c) Result in a cumulatively considerable net increase of
any criteria pollutant for which the project region is
non-attainment under an applicable federal or state
ambient air quality standard (including releasing
emissions which exceed quantitative thresholds for
ozone precursors)?
d) Expose sensitive receptors to substantial pollutant
concentrations?
e) Create objectionable odors affecting a substantial
number of people?
Discussion
a) Conflict with or obstruct implementation of the applicable air quality plan?
Less than Significant Impact. A significant air quality impact may occur if a project is not
consistent with the applicable Air Quality Management Plan (AQMP) or would in some way
obstruct the implementation of the policies or obtainment of the goals of that plan. The proposed
project is located within the City of Newport Beach, California. The city is located in the South
Coast Air Basin (Basin), which is within the jurisdiction of the South Coast Air Quality
Management District (SCAQMD). The SCAQMD is the agency principally responsible for
comprehensive air pollution control in the Basin. To that end, the SCAQMD, a regional agency,
works directly with the Southern California Association of Governments (SCAG), county
transportation commissions, local governments, and cooperates actively with all state and federal
government agencies. The SCAQMD develops rules and regulations, establishes permitting
requirements, inspects emissions sources, and enforces such measures though educational
programs or fines, when necessary. SCAQMD and SCAG are responsible for preparing the
AQMP, which addresses federal and state Clean Air Act (CAA) requirements. Pursuant to these
requirements, the SCAQMD is required to reduce emissions of criteria pollutants for which the
Basin is in non-attainment. The AQMP details goals, policies, and programs for improving air
quality in the Basin.
The 2012 AQMP is currently the most recent plan for the Basin, and was adopted by the
SCAQMD Governing Board on December 7, 2012. The 2012 AQMP was prepared to
accommodate growth, to reduce the high levels of pollutants in the Basin, to meet federal and
state air quality standards, and to minimize the fiscal impact that pollution control measures have
on the local economy. It builds on the approaches taken from the previous 2007 AQMP and sets
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3. Environmental Checklist
forth a comprehensive and integrated program that will lead the Basin into compliance with the
federal 24-hour PM2.5 air quality standard, and to provide an update to the Basin’s commitments
towards meeting the federal 8-hour ozone standards. SCAG, which is the regional metropolitan
planning organization for the Southern California area, has established the assumptions for
growth, in terms of demographic growth and associated air quality impacts, and these
assumptions are utilized in SCAQMD’s AQMP.
Since the forecasted growth in SCAQMD’s AQMP for the Basin relies on SCAG’s regional
growth forecasts, and because SCAG’s growth forecasts are based upon, among other things, land
uses specified in city general plans, a project that is consistent with the land use designated in a
city’s general plan would also be consistent with the AQMP growth projections. As discussed in
Chapter 2 (Project Description), the proposed project would improve water quality through water
conservation, runoff reduction and restoration. Specifically, the proposed project would include a
wetland that would treat both dry and wet weather flows in Big Canyon, and would eliminate the
storm drain-associated vector habitat. The proposed project would contain a pump station, and a
primary treatment structure. Given that the proposed project is an infrastructure project that
serves only to treat contaminated water and improve the functionality of the wetland;
implementation of the proposed project would not result in any additional population or housing
growth in the project area that has not been accounted for in the City of Newport Beach General
Plan. Consequently, as no growth-inducing development or land use would occur under the
project, implementation of the project would not conflict with or obstruct the implementation of
SCAQMD’s AQMP.
In addition, SCAQMD regional significance thresholds were designed to assist SCAQMD in
determining if a project would worsen air quality conditions in the Basin. The determination of
AQMP consistency is primarily concerned with the long-term influence of the proposed project
on air quality in the Basin. As discussed under Question 3(b) below, the proposed project would
not result in significant regional construction emissions and would not interfere with the
attainment of air quality standards. Thus, the project’s construction activities would not conflict
with or obstruct implementation of the AQMP. Overall, the proposed project would result in a
less than significant impact related to the AQMP.
b) Violate any air quality standard or contribute substantially to an existing or
projected air quality violation?
Less than Significant Impact. A project may have a significant impact where project-related
emissions would exceed federal, state, or regional standards or thresholds, or where project-
related emissions would substantially contribute to an existing or projected air quality violation.
As the proposed project consists of the installation of a surface water treatment system, culvert
improvement and restoration activities, potential air quality impacts associated with the project
would only occur during the construction phase as the operation of construction equipment would
result in additional air emissions in the region. Once construction activities have been completed,
operation of the proposed project would not involve any direct pollutant emissions sources onsite.
In addition, vehicle emissions would be generated by worker trips to and from the project area for
routine maintenance of the dosing station, including removal of sediment and debris from the
stilling basin. These maintenance trips are anticipated to occur only once a month. As such, the
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3. Environmental Checklist
mobile emissions generated during project operations would be negligible as discussed below
under Question 3(c).
Construction of the proposed project is expected to last approximately five months and is
tentatively scheduled to begin in September 2016 and continue through January 2017.
Construction activities would commence with site preparation and clearance (approximately 2
weeks), followed by excavation and grading (approximately five weeks); culvert extension (6
weeks); dry weather diversion structures and external piping (2 weeks), construction of
bioretention cell liner and piping (2 weeks), bioretention cell media placement (2 weeks),
bioengineering structure construction (2 weeks), OCSD dosing station installation (6 weeks) and
site vegetation restoration (4 weeks). Several of these activities will run concurrently to achieve
the overall construction schedule of approximately five months.
Criteria air pollutants are defined as pollutants for which the federal and state governments have
established ambient air quality standards for outdoor concentrations to protect public health.
These standards are designed to protect the most sensitive persons from illness or discomfort.
Pollutants of concern include carbon monoxide (CO), nitrous oxides (NOx), particulate matter
that is 10 microns or less in diameter and 2.5 microns or less in diameter (PM10 and PM2.5), sulfur
oxides (SOx), and reactive organic gasses (ROG). Construction activities associated with the
project involving site preparation and excavation would primarily generate respirable particulate
matter (PM10) emissions. Mobile source emissions (use of diesel-fueled equipment onsite, and
traveling to and from the construction site) would primarily generate oxides of nitrogen (NOx)
emissions. The amount of emissions generated on a daily basis would vary, depending on the
amount and types of construction activities occurring at the same time.
It is mandatory for all construction projects in the Basin to comply with SCAQMD Rule 403
(Fugitive Dust) for controlling fugitive dust emissions. Specific Rule 403 control requirements
include, but are not limited to, applying water in sufficient quantities to prevent the generation of
visible dust plumes, applying soil binders to uncovered areas, reestablishing ground cover as
quickly as possible, and maintaining effective cover over exposed areas. Site watering and
application of soil binders would reduce the particulate matter from becoming airborne, while
washing of transport vehicle tires and undercarriages would reduce re-entrainment of construction
dust onto the local roadway network.
The analysis of daily construction emissions has been prepared utilizing the California Emissions
Estimator Model (CalEEMod). CalEEMod was used to determine whether short-term
construction-related emissions of criteria air pollutants associated with the proposed project
would exceed SCAQMD’s applicable regional thresholds and where mitigation would be
required. Modeling was based on project-specific data, when available. Where project-specific
information was not available, default model settings were used to estimate criteria air pollutant
and ozone precursor emissions. For the purpose of this analysis, the construction emissions
occurring on a peak (worst-case) day over the entire project construction period were estimated
and evaluated against the applicable SCAQMD significance thresholds.
The daily emissions that are estimated to occur on peak construction days for each construction
phase of the proposed project are shown in Table 3-1. These calculations take into account that
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-10 ESA / Project No. 130934
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3. Environmental Checklist
appropriate dust control measures under SCAQMD Rule 403 would be implemented by the
project during each phase of construction.
TABLE 3-1
PROJECT PEAK DAY CONSTRUCTION EMISSIONS
Pounds per Day
Emissions Source ROG NOx CO SOx PM10 PM2.5
Site Preparation Clearing and Grubbing
Total Daily Peak Emissions 3.23 35.07 17.73 0.04 9.39 3.37
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Excavation and Grading
Total Daily Peak Emissions 2.23 25.74 13.48 0.03 8.99 3.01
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Culvert Extension
Total Daily Peak Emissions 1.25 15.82 8.17 0.02 1.98 0.71
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Dry Weather Structures and External Piping
Total Daily Peak Emissions 0.39 4.30 3.36 0.01 0.25 0.21
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioretention Cell Liner and Piping
Total Daily Peak Emissions 1.17 15.65 8.24 0.03 5.76 1.02
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioretention Cell Media Placement
Total Daily Peak Emissions 1.24 16.78 5.89 0.02 0.63 0.53
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioengineering Structure Construction
Total Daily Peak Emissions 1.27 18.01 9.36 0.03 7.83 1.26
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
OCSD Dosing Station Installation
Total Daily Peak Emissions 2.62 31.74 15.01 0.04 9.17 3.19
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Site Vegetation Installation
Total Daily Peak Emissions 2.46 28.10 11.82 0.03 4.04 2.56
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
ROG = reactive organic gas; NOx = nitrogen oxides; CO = carbon monoxide; SO2 = sulfur dioxide; PM10 = particulate matter
less than 10 microns; PM2.5 = particulate matter less than 2.5 microns; lbs/day = pounds per day
NOTE: See Appendix B for CalEEMod output.
SOURCE: ESA, 2016
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-11 ESA / Project No. 130934
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3. Environmental Checklist
As noted, some of the construction phases will run concurrently to complete the construction
schedule on time. Table 3-2 shows the daily emissions that are estimated to occur on peak
construction days of the overlapping construction phases.
TABLE 3-2
CONCURRENT CONSTRUCTION PEAK DAY CONSTRUCTION EMISSIONS
Pounds Per Day
ROG NOx CO SOx PM10 PM2.5
Culvert Extension & Dry Weather Diversion
Culvert Extension 1.25 15.82 8.17 0.02 1.98 0.71
Dry Weather 0.39 4.30 3.36 0.01 0.25 0.21
Total 1.65 20.12 11.53 0.03 2.24 0.92
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Dry Weather Diversion & Bioretention Cell Liner
Dry Weather Diversion 0.39 4.30 3.36 0.01 0.25 0.21
Bioretention Cell Liner 1.17 15.65 8.24 0.03 5.76 1.02
OCSD Station 2.62 31.74 15.01 0.04 9.17 3.19
Total 4.18 51.69 26.61 0.07 15.18 4.41
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioretention Cell Media & OCSD Station Installation
Bioretention Cell Media 1.24 16.78 5.89 0.02 0.63 0.53
OCSD Station 2.62 31.74 15.01 0.04 9.17 3.19
Total 3.86 48.52 20.90 0.06 9.80 3.72
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioengineering Structure & OCSD Station Installation
Bioengineering 1.27 18.01 9.36 0.03 7.83 1.26
OCSD Station 2.62 31.74 15.01 0.04 9.17 3.19
Total 3.89 49.75 24.37 0.07 17.00 4.45
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
Bioengineering Structure & OCSD Station Installation
Bioengineering 1.27 18.01 9.36 0.03 7.83 1.26
OCSD Station 2.62 31.74 15.01 0.04 9.17 3.19
Restoration 2.46 28.10 11.82 0.03 4.04 2.56
Total 6.35 77.86 36.19 0.10 21.04 7.01
Significance Threshold 75 100 550 150 150 55
Significant Impact? No No No No No No
ROG = reactive organic gas; NOx = nitrogen oxides; CO = carbon monoxide; SO2 = sulfur dioxide; PM10 = particulate
matter less than 10 microns; PM2.5 = particulate matter less than 2.5 microns; lbs/day = pounds per day
NOTE: See Appendix B for CalEEMod output.
SOURCE: ESA, 2016
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-12 ESA / Project No. 130934
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3. Environmental Checklist
As shown in Table 3-1 and Table 3-2, the peak daily regional emissions generated during project
construction for individual phases, as well as those that overlap, would not exceed the SCAQMD
daily significance thresholds for ROG, NOX, CO, SOx, PM2.5 and PM10. Since construction
emissions would not exceed the SCAQMD thresholds, the regional impacts related to air quality
during project construction activities would be less than significant.
c) Result in a cumulatively considerable net increase of any criteria pollutant for
which the project region is non-attainment under an applicable federal or state
ambient air quality standard (including releasing emissions which exceed
quantitative thresholds for ozone precursors)?
Less than Significant Impact. With respect to air quality, a significant impact may occur if the
project would add a considerable cumulative contribution to federal or state non-attainment
pollutants. Because the Basin is currently classified as a state nonattainment area for ozone, PM10,
and PM2.5, cumulative development consisting of the proposed project along with other
reasonably foreseeable future projects in the Basin as a whole could violate an air quality
standard or contribute to an existing or projected air quality violation. With respect to
determining the significance of the proposed project’s contribution to regional emissions, the
SCAQMD neither recommends quantified analyses of cumulative construction emissions nor
provides methodologies or thresholds of significance to be used to assess cumulative construction
impacts. Instead, the SCAQMD recommends that a project’s potential contribution to cumulative
impacts should be assessed utilizing the same significance criteria as those for project specific
impacts. Furthermore, SCAQMD states that if an individual development project generates less
than significant construction or operational emissions then the development project would not
generate a cumulatively considerable increase in emissions for those pollutants for which the
Basin is in nonattainment.
As discussed under Question 3(b) above, the proposed project would not generate construction
emissions that would exceed the SCAQMD’s recommended thresholds. Once construction
activities have been completed, operation of the proposed project would not involve any direct
pollutant emissions sources onsite. In addition, because mobile emissions generated from worker
trips to and from the project area for routine maintenance of the treatment structures are
anticipated to only occur once a month, the mobile emissions generated would be negligible. As
such, project operations would not generate substantial pollutant emissions that would exceed
SCAQMD’s applicable regional thresholds. Therefore, the proposed project would not generate a
cumulatively considerable increase in emissions of the pollutants for which the Basin is in
nonattainment, and impacts would be less than significant.
d) Expose sensitive receptors to substantial pollutant concentrations?
Less than Significant Impact. A significant impact may occur if a project were to generate
pollutant concentrations to a degree that would significantly affect sensitive receptors. Sensitive
receptors are populations that are more susceptible to the effects of air pollution than are the
population at large. The SCAQMD identifies the following as sensitive receptors: long-term
health care facilities, rehabilitation centers, convalescent centers, retirement homes, residences,
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-13 ESA / Project No. 130934
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3. Environmental Checklist
schools, playgrounds, child care centers, and athletic facilities. The nearest and most notable off-
site sensitive receptors to the project would be the existing residential uses located approximately
46 feet northeast of the project site.
Localized Construction Emissions
Emissions from construction activities have the potential to generate localized emissions that may
expose sensitive receptors to harmful pollutant concentrations. The SCAQMD has developed
localized significance thresholds (LSTs) that are based on the amount of pounds of emissions per
day that can be generated by a project that would cause or contribute to adverse localized air
quality impacts. These localized thresholds, which are found in the mass rate look-up tables in the
Final Localized Significance Threshold Methodology document prepared by the SCAQMD, apply
to projects that are less than or equal to five acres in size and are only applicable to a project’s on-
site emissions for the following criteria pollutants: NOx, CO, PM10, and PM2.5. LSTs represent
the maximum emissions from a project that are not expected to cause or contribute to an
exceedance of the most stringent applicable federal or state ambient air quality standards, and are
developed based on the ambient concentrations of that pollutant for each source receptor area
(SRA) within the Basin. The project area, which consists of an approximately 5 acres, is located
in the City of Newport Beach (SRA 18).
The LSTs developed by SCAQMD are provided for the following distances from the source of
emissions: 25 meters, 50 meters, 100 meters, 200 meters, and 500 meters. Additionally, the LSTs
at these distances also vary based on the size of the project site. The SCAQMD has provided
LSTs for sites that are 1-acre, 2-acre, and 5-acre in size. As the total construction work area
would be approximately 5 acres, the LSTs for a five-acre site is used for this analysis. The nearest
and most notable off-site sensitive receptors that could potentially be subject to localized air
quality impacts associated with construction of the proposed project would be the existing
residential uses located approximately 45 feet northeast of the project site. Given the proximity of
these sensitive uses to the construction areas where the surface water treatment system would be
installed, the LSTs for a five-acre site with receptors located within 25 meters (82.02 feet) are
used to address the potential localized air quality impacts associated with the project’s
construction-related NOx, CO, PM10, and PM2.5 emissions.1
As discussed in Question 3(b) above, it was determined that a worst-case construction day for the
proposed project would include emissions from the entire 5-acre construction site. However,
whereas the construction emissions analysis conducted under Question 3(b) pertained to the
project’s total daily mass emissions, the LST analysis is concerned with a project’s localized air
quality impacts.
The peak daily emissions generated during construction activities were estimated using
CalEEMod and are shown in Table 3-3. As LSTs are only concerned with a project’s on-site
1 Although the existing sensitive uses (i.e., residential uses) located northeast of the project site would be located
closer than 25 meters from the project’s construction areas, the SCAQMD’s LST methodology indicates that projects
with boundaries located closer than 25 meters to the nearest receptor should use the LSTs for receptors located at 25
meters.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-14 ESA / Project No. 130934
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3. Environmental Checklist
emissions, the emissions shown in Table 3-4 account for off-road equipment operating and
fugitive dust. Table 3-4 shows the off-road equipment operating and fugitive dust emissions from
those construction activities that will overlap.
TABLE 3-3
LOCALIZED CONSTRUCTION POLLUTANT EMISSIONS
Pounds Per Day
Construction Phase NOx CO PM10 PM2.5
Site Prep Clearing and Grubbing 27.12 14.28 3.93 2.67
Excavation and Grading 20.20 8.82 3.56 2.32
Culvert Extension 14.40 6.62 0.56 0.52
Dry Weather Diversion Structures 4.29 3.16 0.22 0.20
Bioretention Cell Liner and Piping 10.12 3.78 0.36 0.33
Bioretention Cell Media Placement 16.75 5.50 0.56 0.52
Bioengineering Structure Construction 10.31 3.54 0.35 0.32
OCSD Dosing Station Installation 26.19 10.35 3.74 2.49
Site Vegetation and Restoration 25.54 9.26 3.69 2.44
Peak Day Localized Emissions 27.12 14.28 3.93 2.67
City of Newport Localized Significance
Threshold
197 1,711 14 9
Exceed Threshold? No No No No
See Appendix B for CalEEMod output.
TABLE 3-4
LOCALIZED CONCURRENT CONSTRUCTION POLLUTANT EMISSIONS
Pounds Per Day
Construction Phase NOx CO PM10 PM2.5
Culvert Extension & Dry Weather Diversion 18.69 9.78 0.78 0.72
Dry Weather Diversion & Bioretention Cell Liner & OCSD
Dosing Station
40.60 17.29 4.32 3.02
Bioretention Cell Media & OCSD Dosing Station 42.94 15.85 4.31 3.01
Bioengineering Structure & OCSD Dosing Station 36.50 13.89 4.09 2.81
Bioengineering Structure & OCSD Dosing Station &Site
Restoration
62.03 23.15 7.78 5.25
OCSD Dosing Station & Site Restoration 51.73 19.61 7.43 4.93
Peak Day Localized Emissions 62.03 23.15 7.78 5.25
City of Newport Localized Significance Threshold 197 1,711 14 9
Exceed Threshold? No No No No
See Appendix B for CalEEMod output.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-15 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
As shown in Tables 3-3 and 3-4, the peak daily emissions generated during project construction
activities would not exceed the applicable construction LSTs. Therefore, localized air quality
impacts from the project’s construction activities on the surrounding off-site sensitive receptors
would be less than significant.
Localized Traffic-Related Emissions
Construction of the proposed surface water treatment system is not anticipated to result in
substantial air quality impacts to the public with respect to traffic congestion. The proposed
project limits the construction trips to distinct roads. Haul trucks would access the site from the
intersection of San Joaquin Road and Jamboree Road west on San Joaquin Road to Back Bay
Drive, and then travel north on Back Bay Drive to the Big Canyon Trail maintenance road
entrance. Trucks would follow the maintenance road east to the construction staging area. It is
estimated that approximately 20 daily haul truck trips and up to 1,000 total haul truck trips for
material deliveries would occur over the course of construction. No work is expected to occur
within city streets. Overall, the proposed project would result in a less than significant impact
related to localized, traffic-related pollutant concentrations during construction.
Toxic Air Contaminants
A substance is considered toxic if it has the potential to cause adverse health effects in humans. A
toxic substance released into the air is considered a toxic air contaminant (TAC). TACs are
identified by state and federal agencies based on a review of available scientific evidence. In the
State of California, TACs are identified through a two-step process that was established in 1983
under the Toxic Air Contaminant Identification and Control Act. This two-step process of risk
identification and risk management was designed to protect residents from the health effects of
toxic substances in the air.
Construction of the proposed project would result in short-term diesel exhaust emissions from
off-road heavy-duty equipment. Diesel exhaust is considered a TAC. Construction would result in
the generation of diesel exhaust emissions from the use of off-road diesel equipment required for
site preparation and excavation, and other construction activities.
The dose to which sensitive receptors are exposed is the primary factor used to determine health
risk. Dose is a function of the concentration of a substance or substances in the environment and
the extent of exposure that person has with the substance. Dose is positively correlated with time,
meaning that a longer exposure period would result in a higher exposure level for the maximally
exposed individual. Thus, the risks estimated for a maximally exposed individual are higher if a
fixed exposure occurs over a longer period of time. According to the Office of Environmental
Health Hazard Assessment (OEHHA), health risk assessments, which determine the exposure of
sensitive receptors to toxic emissions, should be based on a 70-year exposure period; however,
such assessments should be limited to the period/duration of activities associated with the
proposed project. Construction of the entire project would occur over approximately a five month
period, and would be separated into 9 different phases. As such, the project’s construction
activities would not be permanently stationed at any one location but instead would occur at
different locations depending on the phase. Thus, the duration of the proposed construction
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-16 ESA / Project No. 130934
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3. Environmental Checklist
activities at any one site would only constitute a small percentage of the total 70-year exposure
period. Thus, diesel particulates from construction activities would not be anticipated to result in
the exposure of sensitive receptors to levels that exceed applicable standards, and impacts would
be less than significant.
e) Create objectionable odors affecting a substantial number of people?
Less than Significant Impact. A significant impact may occur if objectionable odors occur
which would adversely impact sensitive receptors. According to the SCAQMD CEQA Air
Quality Handbook, land uses associated with odor complaints typically include agricultural uses,
wastewater treatment plants, food processing plants, chemical plants, composting, refineries,
landfills, dairies, and fiberglass molding. As the proposed project consists of the installation of
infrastructure for the treatment of water and restoration of the surrounding area, the proposed
project is not a type of use identified by the SCAQMD as being associated with odors. Thus, the
proposed project would not result in objectionable odors during operations, and this impact would
be less than significant.
During construction of the proposed project, exhaust from equipment may produce discernible
odors typical of most construction sites. Such odors would be a temporary source of nuisance to
adjacent uses, but would not affect a substantial number of people. As odors associated with
project construction would be temporary and intermittent in nature, the odors would not be
considered to be a significant environmental impact. Therefore, impacts associated with
objectionable odors would be less than significant.
Resources
South Coast Air Quality Management District (SCAQMD), Final Localized Significance
Threshold Methodology, Appendix C – Mass Rate LST Look-up Tables. October 2009.
South Coast Air Quality Management District (SCAQMD), Final 2012 Air Quality Management
Plan. February 2013.
South Coast Air Quality Management District (SCAQMD), SCAQMD Air Quality Significance
Thresholds. March 2015. Website: http://www.aqmd.gov/home/regulations/ceqa/air-
quality-analysis-handbook. Accessed on February 12, 2016.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-17 ESA / Project No. 130934
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3. Environmental Checklist
3.4 Biological Resources
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
4. BIOLOGICAL RESOURCES — Would the project:
a) Have a substantial adverse effect, either directly or
through habitat modifications, on any species
identified as a candidate, sensitive, or special-status
species in local or regional plans, policies, or
regulations, or by the California Department of Fish
and Game or U.S. Fish and Wildlife Service?
b) Have a substantial adverse effect on any riparian
habitat or other sensitive natural community
identified in local or regional plans, policies,
regulations or by the California Department of Fish
and Game or U.S. Fish and Wildlife Service?
c) Have a substantial adverse effect on federally
protected wetlands as defined by Section 404 of the
Clean Water Act (including, but not limited to, marsh,
vernal pool, coastal, etc.) through direct removal,
filling, hydrological interruption, or other means?
d) Interfere substantially with the movement of any
native resident or migratory fish or wildlife species or
with established native resident or migratory wildlife
corridors, or impede the use of native wildlife nursery
sites?
e) Conflict with any local policies or ordinances
protecting biological resources, such as a tree
preservation policy or ordinance?
f) Conflict with the provisions of an adopted Habitat
Conservation Plan, Natural Community Conservation
Plan, or other approved local, regional, or state
habitat conservation plan?
Discussion
The following evaluation is a summary of the findings provided in the Biological Resources
Technical Report prepared by ESA in January 2016. This report is provided in Appendix C.
a) Have a substantial adverse effect, either directly or through habitat modifications,
on any species identified as a candidate, sensitive, or special status species in local or
regional plans, policies, or regulations, or by the California Department of Fish and
Game or U.S. Fish and Wildlife Service?
Less than Significant with Mitigation Incorporated. No plant or wildlife species listed as state
or federally threatened, endangered, or candidate species was observed within the project area,
and no US Fish and Wildlife Service (USFWS)-designated Critical Habitat occurs onsite.
Therefore, the project would not affect state or federally listed species or USFWS Critical
Habitat.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-18 ESA / Project No. 130934
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3. Environmental Checklist
No species covered by the Orange County Central-Coastal Natural Community Conservation
Plan/Habitat Conservation Plan (NCCP/HCP) were identified in the project area; therefore, the
project would not affect species covered by the Orange County Central-Coastal NCCP/HCP.
Three California Species of Special Concern were observed within the riparian forest habitat
onsite, including yellow warbler, yellow-breasted chat, and Cooper’s hawk. These species, as
well as other bird species nesting in the riparian or adjacent upland habitat or in the ornamental
trees just outside of the project boundary could be negatively affected by the project through
temporary loss of habitat during invasive species removal, floodplain grading, replanting, and
construction of water quality, infrastructure and recreational facilities. Indirect impacts from
construction (e.g., noise and increased activity) could also affect nesting bird species during the
breeding season by disrupting breeding behavior, resulting in nest abandonment and loss of
productivity. These potential impacts to nesting birds and vegetation communities would be
considered significant.
Mitigation Measures
BIO-1: Nesting Birds. Impacts to nesting birds would be avoided by conducting all grading and
construction activities outside of the bird breeding season (February 1–August 15). If breeding
season cannot be avoided, the following measures would be followed.
a. During the avian breeding season, a qualified Project Biologist shall conduct a
preconstruction avian nesting survey no more than 10 days prior to vegetation
disturbance or site clearing. If grading or other construction activity begins in the non-
breeding season and proceeds continuously into the breeding season, no surveys shall be
required. However, if there is a break of 10 days or more in grading or construction
activities during the breeding season, a new nesting bird survey shall be conducted before
these activities begin again.
b. The nest survey shall cover all reasonably potential nesting locations on and within 300
feet of the proposed construction activities areas.
c. If an active nest is found during an avian nest survey, a qualified Project Biologist shall
implement a 300-foot minimum avoidance buffer for coastal California gnatcatcher, least
Bell’s vireo, and other passerine birds and a 500-foot minimum avoidance buffer for all
raptor species. Buffer distances for other species would be determined by the Project
Biologist based on the species and its breeding or nesting requirements. The nest site area
shall not be disturbed until the nest becomes inactive or the young have fledged.
BIO-2: Vegetation Communities. The project would impact a total of 2.46 acres of southern
riparian forest, and 0.50 acre of coastal sage scrub. These vegetation communities are both highly
disturbed from a heavy infestation of non-native plants and compacted, saline soils. These low-
quality habitats would be restored to provide habitats with much greater ecological function than
the current conditions. A total of 2.46 acres of southern riparian forest would be mitigated onsite
through substantial habitat restoration (2.03 acres), willow riparian forest habitat creation (0.25
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-19 ESA / Project No. 130934
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3. Environmental Checklist
acre), and riparian habitat enhancement (0.64 acre). Impacts to coastal sage scrub would be
mitigated onsite through restoration of 1.85 acres, which is 1.35 acres in excess of the required
1:1 ratio. Impacts to non-native grassland, disturbed areas, and ornamental vegetation do not
require mitigation (Table 3-5).
TABLE 3-5
MITIGATION FOR IMPACTS TO VEGETATION COMMUNITIES
Plant Communities and Land Cover Types
Impacts
(Acres)1
Required
Mitigation
(1:1 ratio)
Actual
Mitigation
(Acres)
Excess
(Acres)
Southern Riparian Forest (SRF)2 2.46 2.46 2.923 +0.46
Coastal Sage Scrub (CSS) 0.50 0.50 1.85 +1.35
Non-Native Grassland (NNG) 1.20 0.00 0.00 0.00
Disturbed (Existing Roads & Trails) 0.13 0.00 0.00 0.00
Ornamental (ORN) 0.06 0.00 0.00 0.00
Total Acreage of Impacts 4.35 2.96 4.53 +1.81
1 Includes permanent impacts, temporary impacts associated with habitat restoration component, and temporary impacts
associated with construction of water quality facilities and infrastructure.
2 Note that some portions of the existing southern riparian forest habitat are not considered jurisdictional by the Corps/RWQB
and/or CDFW; therefore, refer to Table 5 for detailed impact acreages of jurisdictional resources. 3 Includes 2.03 acres of substantial restoration, 0.25 acre of habitat creation, and 0.64 acre of habitat enhancement.
SOURCE: ESA, 2016
Significance after Mitigation
Less than Significant. Potential impacts to nesting birds and vegetation communities would be
reduced to less than significant with implementation of Mitigation Measures BIO-1 and BIO -2
described above.
b) Have a substantial adverse effect on any riparian habitat or other sensitive natural
community identified in local or regional plans, policies, and regulations or by the
California Department of Fish and Game or U.S. Fish and Wildlife Service?
Less than Significant with Mitigation Incorporated. The proposed project would permanently
impact a total of 1.42 acres due to the implementation of the proposed water quality and
infrastructure components and proposed trails. A total of 2.03 acres would be temporarily
impacted from the riparian habitat restoration component of the project. An additional 0.90 acres
would be temporarily impacted from construction-related activities. The permanent impacts to
sensitive vegetation consist of 0.43 acre of southern riparian forest and 0.26 acre of coastal sage
scrub (Table 3-6). Additional permanent impacts include 0.63 acre of non-native grassland, 0.08
acre of disturbed habitat, and 0.03 acre of ornamental land cover. The temporary impacts
associated with the riparian habitat restoration component consist of primarily (1.77 acres) low-
quality southern riparian forest, but also include 0.14 acre of non-native grassland, 0.06 acre of
low-quality coastal sage scrub, 0.02 acre of disturbed habitat, and 0.03 acre of ornamental land
cover. Restoration of this area would result in much higher quality native willow forest habitat.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-20 ESA / Project No. 130934
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3. Environmental Checklist
Note that some areas of the existing southern riparian forest are not considered jurisdictional by
the Corps/RWCQB and/or CDFW; therefore, refer to Table 3-7, below for detailed impact
acreages of jurisdictional resources. The temporary impacts associated with construction consist
of 0.43 acre of non-native grassland, 0.26 acre of low-quality southern riparian forest, 0.18 acre
of low-quality coastal sage scrub, and 0.03 are of disturbed habitat. These construction-related
temporary impacts include the staging area adjacent to the existing access road on the
southwestern portion of the project area, the staging area adjacent to Jamboree road (the 8-foot
centerline of this area would become a permanent trail after infrastructure construction has been
completed, but the surrounding slopes would be revegetated), and the slopes surrounding the
bioretention cell. These temporary construction impacts would be considered significant.
TABLE 3-6
SUMMARY OF IMPACTS TO VEGETATION COMMUNITIES
Plant Communities/Land Cover Types
Impacts (Acres)
Permanent
Temporary
(Restoration)
Temporary
(Construction) Total Impacts
Southern Riparian Forest (SRF)1 0.43 1.77 0.26 2.46
Coastal Sage Scrub (CSS) 0.26 0.06 0.18 0.50
Non-Native Grassland (NNG) 0.63 0.14 0.43 1.20
Disturbed (Existing Access Roads and Trails) 0.08 0.02 0.03 0.13
Ornamental (ORN) 0.03 0.03 0.00 0.06
Total Acreage of Impacts 1.42 2.03 0.90 4.35
1 Corps/RWQCB/ and/or CDFW and/or CCC jurisdictional habitat
SOURCE: ESA, 2016
Mitigation Measures
Implementation of Mitigation Measure BIO-2 is required.
Significance after Mitigation
With implementation of Mitigation Measure BIO-2, a total of 2.46 acres of southern riparian
forest would be mitigated onsite through substantial habitat restoration (2.03 acres), willow
riparian forest habitat creation (0.25 acre), and riparian habitat enhancement (0.64 acre). Impacts
to coastal sage scrub would be mitigated onsite through restoration of 1.85 acres, which is 1.35
acres in excess of the required 1:1 ratio. Impacts to sensitive vegetation communities would be
less than significant after implementation of Mitigation Measure BIO-2.
c) Have a substantial adverse effect on federally protected wetlands as defined by
Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal
pool, coastal, etc.) through direct removal, filling, hydrological interruption, or
other means?
Less than Significant with Mitigation Incorporated.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-21 ESA / Project No. 130934
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3. Environmental Checklist
Avoidance. Based upon previous project planning and input from the resource agencies,
infrastructure design measures have been implemented to avoid sensitive habitat and species to
the extent practicable. Limitations to avoid the sensitive habitat and species remain due to the
presence of two sewer lines that run across the existing riparian habitat and parallel to Jamboree
Road. The location of the bioretention cell was placed to not impact future maintenance of either
line. The proposed maintenance road/hiking trail has been place outside the jurisdictional wetland
limits and crossing of the creek would now occur over the proposed culvert extension, rather than
through the middle of the creek, which was the original trail location identified in the previous
planning effort.
Because of creek degradation, both the mainflow creek bed incision and the invasion of exotic
species, temporary impacts to the habitat as a result of restoration implementation are
unavoidable. The resulting restored habitat, however, would provide superior ecological benefits.
Permanent Impacts to Jurisdictional Waters & Wetlands. As a result of the water quality
improvement and infrastructure components, the project would permanently impact Waters of the
United States/State which are characterized as southern riparian forest habitat. Impacts to Waters
of the Waters of the United States/State would result from the extension of the culvert into Big
Canyon, installation of the stilling basin and rip-rap energy dissipater, the maintenance road and
turnaround, and construction of the bioretention cell. Table 3-7, Permanent Impacts to
Jurisdictional Areas, defines impact acreages per the regulating resource area. Note, CDFW
riparian includes Corps/RWQCB acreage, and CCC wetlands include CDFW and Corps/RWQCB
jurisdiction. Thus, maximum permanent jurisdictional impacts do not exceed 0.57 acre.
TABLE 3-7
PERMANENT IMPACTS TO JURISDICTIONAL AREAS
Habitat Types Jurisdictional Area Impacts (acres)
Corps/RWQCB Wetlands --
Corps/RWQCB Non-Wetlands 0.24
CDFW Riparian 0.44
CCC Wetland 0.57
SOURCE: ESA, 2015
Temporary Impacts to Jurisdictional Waters & Wetlands. Temporary impacts to
jurisdictional areas would occur from implementation of the riparian habitat restoration
component of the project. This includes the floodplain restoration grading, construction of the
vegetated soil lifts and willow brush matts, and exotic removal activities. Because of the
extensive invasive species presence in both the understory and overstory vegetation, the majority
of impacts are considered beneficial, in that they would result in improved riparian health. Note
that if additional exotic species are found in areas during implementation, temporary disturbances
areas may be slightly higher.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-22 ESA / Project No. 130934
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3. Environmental Checklist
Combined Permanent and Temporary Impacts to Jurisdictional Waters & Wetlands. The
permanent and temporary impacts to jurisdictional waters and wetlands identified above are
considered significant.
Mitigation Measures
BIO-3: Jurisdictional Wetlands. As stated previously, the project has been designed to avoid and
minimize impacts to jurisdictional resources and high-quality habitat to the extent practicable. To
mitigate for unavoidable permanent impacts to Waters of the United States/State, both habitat
creation and enhancement activities would be conducted onsite, as summarized in Table 3-8.
TABLE 3-8
MITIGATION FOR PERMANENT IMPACTS TO JURISDICTIONAL AREAS
Habitat Types
Permanent
Impacts
(acres) Mitigation for Jurisdictional Impacts
Corps/RWQCB Non-Wetlands/CDFW
Riparian/CCC Wetland
0.24 0.25 acre of riparian forest habitat
creation (1:1 mitigation ratio)1
CDFW Riparian only 0.19 0.64 acre of habitat enhancement
(extensive invasive species removal) CCC Wetland only 0.33
1 Fullfills Corps “no net loss” requirement.
SOURCE: ESA, 2015
To offset for permanent losses to 0.24 acre of non-wetland waters of the United States
(Corps/RWQCB), 0.44 acre of CDFW and 0.57 acre of CCC jurisdictional wetlands, the creation
of 0.25 acre of new habitat is proposed directly to the southwest of the proposed bioretention cell.
This would satisfy the federal mandate for no net loss of wetlands by the Corps. The deficit
acreage (0.19 acre for CDFW and 0.33 acre for CCC) would be satisfied through the removal of
non-native vegetation in adjacent riparian and seed source areas (i.e., riparian habitat
enhancement). This would include removal of the Brazilian peppertrees both east of Jamboree
Road and on the north slopes of the canyon west of Jamboree Road that are the primary source of
invasive seeds for Big Canyon. In addition, understory invasives not mapped by Dudek, including
pampas grass, periwinkle, and English ivy, are prevalent throughout the project area. These
species would be removed as part of the enhancement activities. Approximately 0.64 acre of
invasive removal of the 1.07 acres available would be considered mitigation for unavoidable
permanent impacts. Enhancement activities are distinguished from the restoration activities
proposed (not mitigation) in that restoration would require grading and extensive soil remediation
to achieve full habitat functioning, and enhancement areas would not.
Jurisdictional areas temporarily impacted as a result of construction of the water quality or
infrastructure-related components of the project would be restored to native habitat at a 1:1 ratio.
A full Habitat Restoration Plan describing the Big Canyon restoration as well as habitat
mitigation activities would be submitted for review and approval as part of the environmental
permitting process.
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3. Environmental Checklist
Significance after Mitigation
With implementation of Mitigation Measure BIO-3, impacts to jurisdictional wetlands would be
reduced to less than significant through the restoration of native habitat at a 1:1 ratio.
d) Interfere substantially with the movement of any native resident or migratory fish
or wildlife species or with established native resident or migratory wildlife
corridors, or impede the use of wildlife nursery sites?
Less than Significant with Mitigation Incorporated. The project could temporarily disrupt
wildlife movement during construction of the infrastructure and water quality components as well
as invasive species removal, floodplain grading, and planting in the riparian habitat restoration
area. This temporary disruption to wildlife movement and potential impact on native wildlife
nursery sites would be considered significant.
Mitigation Measure
Implementation of Mitigation Measure BIO-2 is required.
Significance after Mitigation
With implementation of Mitigation Measure BIO-2, onsite habitat would be restored and would
be a higher functioning habitat that can provide cover and forage for migrating wildlife. The
potential impacts to wildlife movement and nursery sites would be reduced to less than
significant.
e) Conflict with any local policies or ordinances protecting biological resources, such
as a tree preservation policy or ordinance?
No Impact. The project would not conflict with the protection of biological resources under the
City of Newport Beach Municipal Code, or the City’s proposed LCP Coastal Land Use Plan
(2015 revised submittal). The proposed project, while not currently included in the Orange
County Central-Coastal NCCP/HCP, would be designated to meet Plan standards. The highly
degraded riparian channel, floodplain, and native vegetation would be restored to better
functioning riparian habitat; restoration of adjacent coastal sage scrub areas would provide
higher-quality upland habitat for wildlife and wetland buffer function; and the water quality
facilities would greatly improve the hydrology and water quality of the creek. Therefore, the
project would not conflict with the provisions of any local policies or ordinances protecting
biological resources or any NCCP/HCPs.
f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural
Community Conservation Plan, or other approved local, regional, or state habitat
conservation plan?
No Impact. The project would not conflict with the protection of biological resources under the
City of Newport Beach Municipal Code, or the City’s proposed LCP Coastal Land Use Plan
(2015 revised submittal). The proposed project, while not currently included in the Orange
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-24 ESA / Project No. 130934
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3. Environmental Checklist
County Central-Coastal NCCP/HCP, would be designated to meet Plan standards. The highly
degraded riparian channel, floodplain, and native vegetation would be restored to better
functioning riparian habitat; restoration of adjacent coastal sage scrub areas would provide
higher-quality upland habitat for wildlife and wetland buffer function; and the water quality
facilities would greatly improve the hydrology and water quality of the creek. Therefore, the
project would not conflict with the provisions of any local policies or ordinances protecting
biological resources or any NCCP/HCPs.
Resources
City of Newport Beach, Local Coastal Program, Coastal Land Use Plan, Amended February
2009. Website:
http://www.newportbeachca.gov/PLN/LCP/Internet%20PDFs//CLUP_Cover%20and%20T
able%20of%20Contents.pdf. Accessed on February 12, 2016.
ESA, Biological Resources Technical Report, Big Canyon Habitat Restoration and Water Quality
Improvement Project, January 2016.
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3. Environmental Checklist
3.5 Cultural Resources
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
5. CULTURAL RESOURCES — Would the project:
a) Cause a substantial adverse change in the
significance of a historical resource as defined in
§15064.5?
b) Cause a substantial adverse change in the
significance of an archaeological resource pursuant to
§15064.5?
c) Directly or indirectly destroy a unique paleontological
resource or site or unique geologic feature?
d) Disturb any human remains, including those interred
outside of formal cemeteries?
Discussion
The following evaluation is a summary of the findings provided in the Cultural Resources Study
prepared by ESA in January 2016. This report contains confidential information and is not for
public distribution.
a) Cause a substantial adverse change in the significance of a historical resource as
defined in 15064.5?
Less than Significant with Mitigation Incorporated. No built resources, archaeological sites,
or tribal cultural resources were identified in the project area as a result of the current study,
which included archival research, pedestrian survey, a search of the Sacred Lands File at the
Native American Heritage Commission, and Native American outreach. That said, numerous
prehistoric archaeological sites do occur throughout the area. A records search at the South
Central Coast Information Center (SCCIC) shows that 35 archaeological resources have been
recorded in a 1 mile radius, and that 5 of these occur with 0.15 mile. While most of these occur
on ridgetops and mesas above and outside the project area, Native American representatives and
the Sacred Lands File search indicate that the area contains sensitive archaeological resources.
Given this, and given the fact that the archaeological survey only addressed resources visible on
the surface, and that certain heavily vegetated areas were not accessible for survey, there is a
potential, though small, that earthmoving activity could impact buried archaeological resources.
This potential impact on unknown archaeological resources would be considered significant.
Mitigation Measures
CR-1: Archaeological Monitoring. An archaeological monitor (working under the direct
supervision of a Secretary of the Interior-qualified archaeologist [USDI 2008]) shall be retained
to observe all ground-disturbing activities, including but not limited to brush clearance,
vegetation removal, grubbing, grading, and excavation. Prior to start of ground-disturbing
activities, the archaeologist shall conduct cultural resources sensitivity training for all
construction personnel. Construction personnel shall be informed of the types of archaeological
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3. Environmental Checklist
resources that may be encountered, and of the proper procedures to be enacted in the event of an
inadvertent discovery of archaeological resources or human remains. The City shall ensure that
construction personnel are made available for and attend the training and retain documentation
demonstrating attendance.
Archaeological monitoring shall be conducted by an archaeologist familiar with the types of
archaeological resources that could be encountered within the project site. The qualified
archaeologist, in coordination with the City, may reduce or discontinue monitoring if it is
determined that the possibility of encountering buried archaeological deposits is low based on
observations of soil stratigraphy or other factors. The archaeological monitor shall be empowered
to halt or redirect ground-disturbing activities away from the vicinity of a discovery until the
qualified archaeologist has evaluated the discovery and determined appropriate treatment. The
archaeological monitor shall keep daily logs detailing the types of activities and soils observed,
and any discoveries. After monitoring has been completed, the qualified archaeologist shall
prepare a monitoring report that details the results of monitoring. The report shall be submitted to
the City, the Corps, and any Native American groups who request a copy. A copy of the final
report shall be filed at the SCCIC.
If archaeological resources are encountered during monitoring, and if it is determined that the
discovered archaeological resource constitutes a historic property under Section 106 of the NHPA
or a historical resource under CEQA, avoidance and preservation in place is the preferred manner
of treatment. Preservation in place maintains the important relationship between artifacts and
their archaeological context and also serves to avoid conflict with traditional and religious values
of groups who may ascribe meaning to the resource. Preservation in place may be accomplished
by, but is not limited to, avoidance, incorporating the resource into open space, capping, or
deeding the site into a permanent conservation easement. In the event that preservation in place is
demonstrated to be infeasible and data recovery through excavation is the only feasible mitigation
available, a Cultural Resources Treatment Plan would be prepared and implemented by a
qualified archaeologist in consultation with the Corps and the City. The plan will provide for the
adequate recovery of the scientifically consequential information contained in the archaeological
resource. The Corps and the City shall be required to consult with appropriate Native American
representatives in determining treatment for prehistoric or Native American resources to ensure
cultural values ascribed to the resource, beyond that which is scientifically important, are
considered.
CR-2: Native American Monitoring. The City shall retain a Native American monitor to
observe all ground-disturbing activities, including but not limited to brush clearance, vegetation
removal, grubbing, grading, and excavation. The Native American monitor shall be selected from
amongst the Native American groups identified by the NAHC as having affiliation with the
project area. The Native American representative shall be allowed to participate in the cultural
resources sensitivity training, discusses in Mitigation Measure CR-1, and all authorities ascribed
to the archaeological monitor, including the authority to stop work in the event of the discovery
of cultural resources, shall also apply to the Native American monitor. In the event that
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3. Environmental Checklist
archaeological materials are encountered, the Native American monitor shall participate in any
discussions involving treatment and subsequent mitigation.
Significance after Mitigation
With the implementation of Mitigation Measures CR-1 and CR-2, monitoring activities, as well
as subsequent data recovery, if necessary, would reduce potential impacts on historical resources
to less than significant.
b) Cause a substantial adverse change in the significance of an archaeological resource
pursuant to 15064.5?
Less than Significant with Mitigation Incorporated. As mentioned above, no archaeological
resources were identified within the project area. That said, there is the potential to encounter
buried resources during construction. This potential to encounter buried archaeological resources
would be considered a significant impact.
Mitigation Measures
Implementation of Mitigation Measures CR-1 and CR-2 is required.
Significance after Mitigation
The implementation of Mitigation Measures CR-1 and CR-2 would ensure that the project would
have a less than significant impact on unique archaeological resources.
c) Directly or indirectly destroy a unique paleontological resource or site or unique
geologic feature?
Less than Significant with Mitigation Incorporated. The results of the paleontological records
check at the Natural History Museum of Los Angeles County indicate that the project area is
sensitive for paleontological resources. The Monterey Formation underlies younger Quaternary
alluvium within the central portion of Big Canyon, and there are exposures of Monterey
Formation in the Big Canyon walls. While grading operations will not involve substantial
excavation extending into the underlying Monterey Formation within the canyon, or excavations
in the exposures of Monterey Formation in the Big Canyon walls, there is a good chance of
uncovering significant vertebrate fossil remains. Paleontological resources are considered part of
the environment and a project that may directly or indirectly destroy a unique paleontological
resource is a project that may have a significant effect on the environment. Therefore, the
construction activities associated with the proposed project would result in potential significant
impacts on paleontological resources.
Mitigation Measures
CR-3: Paleontological Monitoring. A qualified paleontologist meeting the Society for
Vertebrate Paleontology (SVP) guidelines for professional paleontologist (SVP, 2010) shall be
retained to oversee all mitigation measures related to paleontological resources. That said, both
the paleontological and archaeological monitoring could be carried out by the same person,
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3. Environmental Checklist
presuming the monitor is qualified in both disciplines. During ground disturbing activity, the
qualified paleontologist or paleontological monitor shall conduct spot-checks of exposed
sediments. The purpose would be to determine whether the project would impact the
paleontologically sensitive Monterey Formation. The qualified paleontologist may institute
paleontological monitoring if, based on observations of subsurface stratigraphy or other factors,
he or she determines that the possibility of encountering fossiliferous deposits is high.
Paleontological monitoring would be conducted by a paleontological monitor working under the
supervision of the qualified paleontologist. In the event that monitoring is required, the monitor
shall have the authority to temporarily halt or divert work away from exposed fossils in order to
recover the fossil specimens and shall complete daily monitoring logs outlining the day’s
activities. The qualified paleontologist shall prepare a final monitoring report to be submitted to
the City and filed with the local repository, along with any fossils recovered during construction.
The qualified paleontologist shall also contribute to any construction worker cultural resources
sensitivity training (see Mitigation Measure CR-1) either in person or via a training module
provided to the qualified archaeologist. The training shall include information of the types of
paleontological resources that may be encountered, and the proper procedures to be enacted in the
event of an inadvertent discovery of paleontological resources.
In the event of unanticipated discovery of paleontological resources, the City shall cease ground-
disturbing activities within 100 feet of the find until it can be assessed by the qualified
paleontologist. The qualified paleontologist shall assess the find, implement recovery measures if
necessary, and determine if paleontological monitoring is warranted once work resumes.
Significance after Mitigation
The implementation of Mitigation Measure CR-3 would ensure that the project would have a less
than significant impact on paleontological resources or unique geologic features.
d) Disturb any human remains, including those interred outside formal cemeteries?
No Impact. No human remains were identified in the project area as a result of the archival
research or survey, and it is anticipated that the project would have no impact on human remains.
That said, the area was known to have been used by prehistoric Native Americans. In the unlikely
event that human remains are uncovered during ground disturbing activities, appropriate state law
would apply. Specifically, California Health and Safety Code Section 7050.5 requires that in the
event human remains are discovered, the County Coroner be contacted to determine the nature of
the remains. In the event the remains are determined to be Native American in origin, the Coroner
is required to contact the NAHC within 24 hours to relinquish jurisdiction.
Further, California PRC Section 5097.98, as amended by Assembly Bill 2641, provides
procedures in the event human remains of Native American origin are discovered during project
implementation. PRC Section 5097.98 requires that no further disturbances occur in the
immediate vicinity of the discovery, that the discovery is adequately protected according to
generally accepted cultural and archaeological standards, and that further activities take into
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3. Environmental Checklist
account the possibility of multiple burials. PRC Section 5097.98 further requires the NAHC, upon
notification by a County Coroner, designate and notify a Most Likely Descendant (MLD)
regarding the discovery of Native American human remains. Once the MLD has been granted
access to the site by the landowner and inspected the discovery, the MLD then has 48 hours to
provide recommendations to the landowner for the treatment of the human remains and any
associated grave goods.
In the event that no descendant is identified, or the descendant fails to make a recommendation
for disposition, or if the land owner rejects the recommendation of the descendant, the landowner
may, with appropriate dignity, reinter the remains and burial items on the property in a location
that would not be subject to further disturbance.
Resources
Advisory Council on Historic Preservation, Section 106 of the National Historic Preservation
Act, 1966.
Society of Vertebrate Paleontology, Standard Procedures for the Assessment and Mitigation of
Adverse Impacts to Paleontological Resources, 2010. Website:
https://vertpaleo.org/PDFS/68/68c554bb-86f1-442f-a0dc-25299762d36c.pdf. Accessed on
February 12, 2016.
State of California. California Health and Safety Code Section 7052. Website:
http://law.onecle.com/california/health/7052.html. Accessed on February 12, 2016.
State of California, Public Resources Code Section 5097.98. Website:
http://www.leginfo.ca.gov/cgi-bin/displaycode?section=prc&group=05001-
06000&file=5097.9-5097.991. Accessed on February 12, 2016.
US Department of the Interior, National Park Service, Secretary of the Interior’s Standards and
Guidelines, Archaeology and Historic Preservation. Website:
http://www.nps.gov/history/local-law/arch_stnds_0.htm. Accessed on February 12, 2016.
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3. Environmental Checklist
3.6 Geology, Soils, and Seismicity
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
6. GEOLOGY, SOILS, AND SEISMICITY —
Would the project:
a) Expose people or structures to potential substantial
adverse effects, including the risk of loss, injury, or
death involving:
i) Rupture of a known earthquake fault, as
delineated on the most recent Alquist-Priolo
Earthquake Fault Zoning Map issued by the
State Geologist for the area or based on other
substantial evidence of a known fault? (Refer to
Division of Mines and Geology Special
Publication 42.)
ii) Strong seismic ground shaking?
iii) Seismic-related ground failure, including
liquefaction?
iv) Landslides?
b) Result in substantial soil erosion or the loss of topsoil?
c) Be located on a geologic unit or soil that is unstable,
or that would become unstable as a result of the
project, and potentially result in on- or off-site
landslide, lateral spreading, subsidence, liquefaction,
or collapse?
d) Be located on expansive soil, as defined in
Table 18-1-B of the Uniform Building Code (1994),
creating substantial risks to life or property?
e) Have soils incapable of adequately supporting the use
of septic tanks or alternative wastewater disposal
systems where sewers are not available for the
disposal of wastewater?
Discussion
a) Expose people or structures to potential substantial adverse effects, including the
risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent
Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist
for the area or based on other substantial evidence of a known fault? (Refer
to Division of Mines and Geology Special Publication 42.)
No Impact. Based on a review of the City of Newport Beach General Plan, Safety
Element, the City is located in the northern part of the Peninsular Ranges Province which
is an area that is exposed to risks from multiple earthquake fault zones. The nearest
earthquake that contains an Alquist-Priolo Earthquake Fault Zone is the Newport-
Inglewood fault zone. This fault is located offshore from the City of Newport Beach.
Based on a review of the Special Studies Zones map prepared by the California Division
of Mines and Geology, there are no Alquist-Priolo Earthquake Fault Zones on the project
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-31 ESA / Project No. 130934
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3. Environmental Checklist
site. Therefore, the proposed project would not be exposed to a rupture of a known
earthquake fault.
ii) Strong seismic ground shaking?
Less than Significant Impact. The largest earthquake magnitude within a 100-mile
radius of the project site between 1800 and 2006 was 7.6 magnitude GSI 2006). The
project site is subject to varying ground shaking intensities similar to other areas within
the region. The City requires that all construction meet the latest standards of the
California Building Code (CBC) which considers proximity to potential seismic sources
and the maximum anticipated ground shaking possible. The construction of the proposed
facilities on the project site would be in accordance with applicable City ordinances and
policies and consistent with the most recent version of the CBC which requires structural
design that can accommodate ground accelerations expected from known active faults.
Compliance with the City’s safety design standards as well as the CBC would reduce
potential impacts associated with seismic ground shaking to less than significant.
iii) Seismic-related ground failure, including liquefaction?
Less than Significant Impact. Liquefaction is a secondary earthquake-induced hazard
that occurs when water-saturated soils lose their strength and liquefy during intense and
prolonged ground shaking. Based on a review of the Newport Beach General Plan, the
project site includes areas that are susceptible to liquefaction. Adherence to the CBC and
the City’s Municipal Code requirements would implement proven geotechnical design
measures that would minimize the potential for liquefaction, and potential impacts would
be less than significant.
iv) Landslides?
Less than Significant Impact. Based on a review of the Newport Beach General Plan,
the project site contains a few areas that could be susceptible to landslides. Project
implementation would be required to adhere to the CBC and the City’s Municipal Code
to ensure the potential for landslides is reduce to less than significant.
b) Result in substantial soil erosion or the loss of topsoil?
Less than Significant Impact. During project construction, excavation and grading would be
required. These activities would expose soil to erosive elements such as wind and rain. However,
project construction would be required to comply with existing regulatory requirements that
address soil erosion such as the National Pollutant Discharge Elimination System (NPDES)
program. Any development site, such as the project site, that would disturb one or more acres
would be required to develop and implement a Storm Water Pollution Prevention Plan (SWPPP)
which includes the use of erosion control Best Management Practices to protect surface water and
groundwater from the adverse effects of construction activities.
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3. Environmental Checklist
The erosion control best management practices (BMPs) such as scheduling, preservation of
existing vegetation, hydroseeding, sandbags, fiber rolls, and silt fences would prevent the
exposure of soil to wind and water and reduce the threat of erosion during construction to less
than significant.
Once constructed, the potential for erosion or loss of topsoil is substantially reduced. The project
would include creek restoration activities that would include floodplain restoration, streambank
stabilization and habitat restoration. Floodplain restoration and streambank stabilization activities
would result in flood flow attenuation, stabilization of the north bank of the main channel, and
creation of an active sinous riparian floodplain. The north creek bank at the inlet would be
stabilized using natural bioengineering techniques. Riparian habitat would be restored directly
downstream of the floodplain restoration area through the removal of invasive trees, soil
remediation to reduce plant-limiting sodium levels, and replacement with native riparian species.
The proposed project would reduce the potential for soil erosion or loss of topsoil to less than
significant.
c) Be located on a geologic unit or soil that is unstable, or that would become unstable
as a result of the project, and potentially result in on- or off-site landslide, lateral
spreading, subsidence, liquefaction, or collapse?
Less than Significant Impact. As described above, the development of the proposed structures
would be required to adhere to the CBC and City requirements. These requirements would ensure
that appropriate engineering techniques are implemented to reduce any potential for landslides,
lateral spreading, subsidence, liquefaction or collapse to less than significant.
d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building
Code (1994), creating substantial risks to life or property?
Less than Significant Impact. Although the west side of Big Canyon contains previously
dredged materials from Upper Newport Bay that could contain expansive soils, it is unknown if
the project site contains expansive soil. As stated above, the proposed structures would be
required to comply with the CBC and the City requirements for stable soils. Compliance with
these requirements would reduce the potential impacts to less than significant.
e) Have soils incapable of adequately supporting the use of septic tanks or alternative
wastewater disposal systems where sewers are not available for the disposal of
wastewater?
No Impact. The proposed project does not include septic tanks or alternative waste disposal
systems. As a result, there is no potential for soil failure associated with the installation of septic
tanks or alternative waste disposal systems.
Resources
California Division of Mines and Geology (CDMG), State of California Special Studies Zones,
Newport Beach Quadrangle, 1986. Website:
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3. Environmental Checklist
http://gmw.consrv.ca.gov/shmp/download/quad/NEWPORT_BEACH/maps/NEWPORTB
CH.PDF. Accessed on February 11, 2016.
City of Newport Beach, Newport Beach General Plan, 2006.Website:
http://www.newportbeachca.gov/government/departments/community-
development/planning-division/general-plan-codes-and-regulations/general-plan. Accessed
on February 11, 2016.
Geosoils, Inc (GSI), Geotechnical Feasibility Report: Big Canyon Creek Restoration, Upper
Newport Bay, Newport Beach, County of Orange, California, 2006..
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-34 ESA / Project No. 130934
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3. Environmental Checklist
3.7 Greenhouse Gas Emissions
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
7. GREENHOUSE GAS EMISSIONS —
Would the project:
a) Generate greenhouse gas emissions, either directly or
indirectly, that may have a significant impact on the
environment?
b) Conflict with an applicable plan, policy or regulation
adopted for the purpose of reducing the emissions of
greenhouse gases?
Discussion
Gases that trap heat in the atmosphere are referred to as greenhouse gases (GHGs) because they
capture heat radiated from the sun as it is reflected back into the atmosphere, much like a
greenhouse does. The accumulation of GHGs has been implicated as a driving force for global
climate change. Definitions of climate change vary between and across regulatory authorities and
the scientific community, but in general can be described as the changing of the earth’s climate
caused by natural fluctuations and anthropogenic activities, which alter the composition of the
global atmosphere.
Prominent GHGs contributing to the greenhouse effect are carbon dioxide (CO2), methane (CH4),
nitrous oxide (N2O), hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), perfluorocarbons
(PFCs), and sulfur hexafluoride (SF6). Carbon dioxide is the “reference gas” for climate change,
meaning that emissions of GHGs are typically reported in “carbon dioxide-equivalent” (CO2e)
measures. There is international scientific consensus that human-caused increases in GHGs have
and will continue to contribute to global warming, although there is uncertainty concerning the
magnitude and rate of the warming. Potential global warming impacts in California may include,
but are not limited to, loss in snow pack, sea level rise, more extreme heat days per year, more
high ozone days, more large forest fires, and more drought years. Secondary effects are likely to
include global rise in sea level, impacts to agriculture, changes in disease vectors, and changes in
habitat and biodiversity.
In 2005, in recognition of California’s vulnerability to the effects of climate change, Governor
Schwarzenegger established Executive Order S-3-05, which sets forth a series of target dates by
which statewide emissions of GHG would be progressively reduced, as follows:
• By 2010, reduce GHG emissions to 2000 levels;
• By 2020, reduce GHG emissions to 1990 levels; and
• By 2050, reduce GHG emissions to 80 percent below 1990 levels.
In 2006, California passed the California Global Warming Solutions Act of 2006 (Assembly Bill
No. 32; California Health and Safety Code Division 25.5, Sections 38500, et seq., or AB 32),
which requires CARB to design and implement emission limits, regulations, and other measures,
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-35 ESA / Project No. 130934
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3. Environmental Checklist
such that feasible and cost-effective statewide GHG emissions are reduced to 1990 levels by
2020.
On March 18, 2010, the California Office of Planning and Research (OPR) submitted
amendments to the CEQA Guidelines for GHG emissions, as required by Public Resources Code
section 21083.05. These CEQA Guideline amendments provide guidance to public agencies
regarding the analysis and mitigation of the effects of GHG emissions in draft CEQA documents.
The amendments are relatively modest changes to various portions of the existing CEQA
Guidelines.
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a
significant impact on the environment?
Less than Significant Impact. The proposed project would primarily contribute to global climate
change as a result of emissions of GHGs, primarily CO2, emitted during construction activities
associated with the installation of a surface water treatment system, including a pump station and
culvert improvements. Once construction activities have been completed, operation of the
proposed project would only generate minimal GHG emissions sources from vehicle emissions
associated with worker trips to and from the project area for routine maintenance of the surface
water treatment structure. However, because these trips would only occur once a month, these
GHG emissions would be negligible.
GHG impacts are considered to be exclusively cumulative impacts (CAPCOA, 2008); there are
no non-cumulative GHG emission impacts from a climate change perspective. Thus, the purpose
of this GHG analysis is to determine whether the contribution of GHG emissions by the proposed
project would be cumulatively considerable.
The City of Newport Beach has not adopted any significance criteria or guidelines for GHG
analysis. SCAQMD has issued proposed standards and guidelines, proposing a 10,000 metric ton
per year (MT/year) CO2e threshold for industrial projects for which it is the lead agency.
Additionally, SCAQMD has proposed, a 3,000 MT/year CO2e threshold for residential and
commercial developments (SCAQMD, 2008). For the purpose of this analysis, the project’s total
annual GHG emissions resulting from construction activities have been quantified and evaluated
against the 3,000 MT/year CO2e screening criteria. As was conducted for the proposed project’s
air quality analysis in Question 3 (Air Quality), the project’s construction-related GHG emissions
were estimated for equipment exhaust, truck trips, and worker commute trips using CalEEMod.
The project’s estimated annual GHG emissions during construction are shown in Table 3-9. With
respect to construction GHG emissions, SCAQMD recommends that the total emissions for a
project be amortized over a 30-year period and added to its operational emission estimates
(SCAQMD, 2008). To determine the total construction emissions that would be generated from
the project’s surface water treatment system, the annual GHG emissions under a worst-case
construction scenario was taken to conservatively represent the total emissions that would be
generated from construction of the proposed project. Total construction-related GHG emissions
was calculated to be 103.97 CO2e MT/yr. Amortized over 30 years, the proposed project
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-36 ESA / Project No. 130934
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3. Environmental Checklist
construction-related GHG emissions would be 3.47 CO2e MT/yr. With respect to operational
emissions, the only GHG emissions generated by the proposed project would be periodic
maintenance on-site. This maintenance would include maintenance of the water dosing station,
monitoring the bioretention cell for any debris buildup and maintenance of any invasive or dead
vegetation removal. The periodic maintenance would not be expected to result in higher GHG
emissions than produced by construction activities. Therefore, a conservative estimate of the
operational GHG emissions was chosen as 20% of the annual construction GHG emissions.
TABLE 3-9
ESTIMATED PROJECT CONSTRUCTION GHG EMISSIONS
Emission Source
Proposed Project
EmissionsCO2e (MT/yr)
Construction
Annual Project Construction (Amortized over 30 yrs)a 3.47
Operation 20.79
Total Annual Emissions 24.26
CAPCOA Screening Threshold 3000
Significant Impact? No
NOTES: CO2e= carbon dioxide equivalent; MT/yr = metric tons per year; see Appendix B for CalEEMod
model outputs.
a The total project construction GHG emissions were derived by summing the annual construction
emissions (MT/yr) for all nine phases. Total project construction GHG emissions = 103.97 CO2e
MT/yr. Amortized over 30 years, annual project construction GHG emissions = 3.47 CO2e MT/yr.
As shown in Table 3-9, the proposed project’s total annual GHG emissions resulting from
construction activities and project operation would be approximately 24.26 MT CO2e per year.
Thus, the project’s total annual GHG emissions would not exceed the 3,000 MT of CO2e per year
screening threshold recommended by SCAQMD. Therefore, the proposed project would not
result in the generation of substantial levels of GHG emissions and would not result in emissions
that would adversely affect the statewide attainment of GHG emission reduction goals of AB 32.
This impact would be less than significant.
b) Conflict with an applicable plan, policy or regulation adopted for the purpose of
reducing the emissions of greenhouse gases?
No Impact. The proposed project would generate temporary construction-related GHG emissions
and minimal GHG emissions during operations. Because the proposed project only involves the
installation of surface water treatment infrastructure, culvert improvements and restoration
activities, implementation of the project would not result in, or induce, growth in the project area
that has not been accounted for by the City of Newport Beach. Consequently, no growth-inducing
development or land use that would generate GHG emissions would occur under the project. The
proposed project would not conflict with any adopted plan’s goals of reducing GHG emissions.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-37 ESA / Project No. 130934
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3. Environmental Checklist
Overall, implementation of the proposed project would not conflict with an applicable plan,
policy, or regulation adopted for the purpose of reducing the emissions of GHGs. Therefore, this
impact would be less than significant.
Resources
South Coast Air Quality Management District (SCAQMD), Draft Guidance Document – Interim
CEQA Greenhouse Gas (GHG) Significance Threshold. October 2008.
State of California, Office of Governor, Executive Order S-3-05, 2008. Website:
https://www.gov.ca.gov/news.php?id=1861. Accessed on February 12, 2016.
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3. Environmental Checklist
3.8 Hazards and Hazardous Materials
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
8. HAZARDS AND HAZARDOUS MATERIALS —
Would the project:
a) Create a significant hazard to the public or the
environment through the routine transport, use, or
disposal of hazardous materials?
b) Create a significant hazard to the public or the
environment through reasonably foreseeable upset
and accident conditions involving the release of
hazardous materials into the environment?
c) Emit hazardous emissions or handle hazardous or
acutely hazardous materials, substances, or waste
within one-quarter mile of an existing or proposed
school?
d) Be located on a site which is included on a list of
hazardous materials sites compiled pursuant to
Government Code Section 65962.5 and, as a result,
would it create a significant hazard to the public or the
environment?
e) For a project located within an airport land use plan
or, where such a plan has not been adopted, within
two miles of a public airport or public use airport,
would the project result in a safety hazard for people
residing or working in the project area?
f) For a project within the vicinity of a private airstrip,
would the project result in a safety hazard for people
residing or working in the project area?
g) Impair implementation of or physically interfere with
an adopted emergency response plan or emergency
evacuation plan?
h) Expose people or structures to a significant risk of loss,
injury or death involving wildland fires, including where
wildlands are adjacent to urbanized areas or where
residences are intermixed with wildlands?
Discussion
a) Create a significant hazard to the public or the environment through the routine
transport, use, or disposal of hazardous materials?
Less than Significant Impact. Construction activities associated with the proposed project
would involve site clearing, excavation, grading, and other ground-disturbing activities.
Construction activities would be required for the installation of the project facilities, including the
culvert extension, the bioretention cell liner and piping, and the bioengineering structure
construction. Construction activities would occur for approximately five months within the
project site. The proposed construction activities would require the use of equipment, such as
loaders, excavators, trucks, and other powered equipment, and would therefore use fuels (gasoline
or diesel) and lubricants (oils and greases). All construction equipment would be housed within
the staging area of the project site. The construction equipment on site may require minor
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-39 ESA / Project No. 130934
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3. Environmental Checklist
maintenance during construction activities, which may result in the disposal of hazardous
byproducts from the equipment.
Operation of the proposed facilities would involve the routine and major maintenance of the
wetland basin. This would include the removal of trash, debris, and dying vegetation that interfere
with facility maintenance. Maintenance activities would also include removal of any visual
contamination from floatables, such as oil and grease, and repairs to any flow control structures
as needed to maintain full functionality. Operational activities would involve limited amounts of
hazardous materials used in and transported to the project site. The use of hazardous materials
and substances during construction and operation activities would be subject to federal, state, and
local health and safety requirements for handling, storage, and disposal. Therefore, hazardous
material impacts related to construction activities would be less than significant.
b) Create a significant hazard to the public or the environment through reasonably
foreseeable upset and accident conditions involving the release of hazardous
materials into the environment?
Less than Significant Impact. As discussed above in discussion 3.8(a), limited quantities of
hazardous materials such as gasoline, diesel, oils, and lubricants may be required to operate the
construction equipment. Construction activities would be short-term, and the use of these
materials would cease once construction is complete. The hazardous substances used during
construction would be required to comply with existing federal, state and local regulations
regarding the use and disposal of these materials. In the event of an accidental release during
construction, containment and clean up would be in accordance with existing applicable
regulatory requirements. Project operation would involve minimal transport and use of hazardous
materials onsite. The use of hazardous materials and substances during construction and operation
activities would be subject to federal, state, and local health and safety requirements for handling,
storage, and disposal. Potential impacts to the public or the environment related to reasonably
foreseeable accident conditions involving hazardous materials would be less than significant.
c) Emit hazardous emissions or handle hazardous or acutely hazardous materials,
substances, or waste within one-quarter mile of an existing or proposed school?
Less than Significant Impact. The nearest existing school to the project site is Our Lady Queen
of Angels High School located approximately 0.16 miles north of the project site. In addition,
Corona Del Mar High School is located approximately 0.25 miles north of the project site.
Therefore, there are two schools within one-quarter mile of the proposed project area.
Construction within the project site would include the use of loaders, dozers, haul trucks,
compactors, and water trucks. Hazardous materials, such as oil, solvents, and gasoline, needed for
the maintenance of the construction equipment would be used only in small quantities on the
project site, and the use of hazardous substances would be compliant with City code regulations
and Best Management Practices. Hazardous materials would not be transported on a routine basis.
Construction activities are to last approximately five months; therefore, construction-related
hazardous materials would be only temporarily present on site and subsequently removed after
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-40 ESA / Project No. 130934
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3. Environmental Checklist
construction is completed. Operation of the proposed project would not introduce any hazardous
emissions or materials into the project site. Therefore, the proposed project would result in less
than significant hazardous material-related impacts to schools within a quarter-mile of the project.
d) Be located on a site which is included on a list of hazardous materials sites compiled
pursuant to Government Code Section 65962.5 and, as a result, would it create a
significant hazard to the public or the environment?
No Impact. Pursuant to Government Code 65962.5, environmental regulatory database lists were
reviewed to identify and locate properties with known hazardous substance contamination within
the proposed project area (California Government Code, Section 65960 et seq.) (see Appendix D).
A review of the Department of Toxic Substances Control’s (DTSC) Hazardous Waste and
Substances List – Site Cleanup (Cortese List) indicates that identified hazardous material sites are
not located within the project area (DTSC, 2007). There was a formerly leaking underground
storage tank across the street at Big Canyon Country Club, but the case has closed as of May 15,
2001 (EDR, 2016). A review of the DTSC EnviroStor and the State Water Resources Control
Board GeoTracker online databases did not indicate any open cleanup sites or hazardous waste
facilities within the vicinity of the project area. Therefore, since the project is not located on a list
associated with hazardous materials, no impacts would occur.
e) For a project located within an airport land use plan or, where such a plan has not
been adopted, within two miles of a public airport or public use airport, would the
project result in a safety hazard for people residing or working in the project area?
No Impact. The nearest public airport to the project site is John Wayne Airport (JWA),
approximately 2.5 miles north of the site. The John Wayne Airport Safety Compatibility Zones
are defined in the Airport Environs Land Use Plan for JWA (ALUC, 2013). The proposed project
is not located within any Safety Compatibility Zones for JWA. No impacts to safety hazards for
people residing or working in the project area would occur.
f) For a project within the vicinity of a private airstrip, would the project result in a
safety hazard for people residing or working in the project area?
No Impact. The proposed project is not located within the vicinity of a private airstrip. The
nearest private airstrip to the project site is the L.A. Times Costa Mesa Heliport approximately 5
miles northwest of the project site (www.tollfreeairline.com). No airstrip related hazard impacts
would occur.
g) Impair implementation of or physically interfere with an adopted emergency
response plan or emergency evacuation plan?
No Impact. The Newport Beach Fire Department prepared an Emergency Operations Plan (EOP)
that was adopted by the City of Newport Beach in September 2011. The purpose of the EOP is to
provide guidance for the City’s response to extraordinary emergency situations associated with
natural disasters, technological incidents, and national security emergencies in or affecting the
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3. Environmental Checklist
City of Newport Beach. The EOP also shows the City’s emergency evacuation routes in the event
of a tsunami. The project site is located along Jamboree Road, a designated emergency
evacuation route.
The proposed project would be constructed completely within the proposed project boundary.
Construction equipment as well as haul trucks would access the site from Jamboree Road, and
then travel west at the intersection of San Joaquin Road and Jamboree Road onto San Joaquin
Road. Construction vehicles would travel to Back Bay Drive, and then travel north on Back Bay
Drive to the Big Canyon Trail maintenance road entrance. Construction vehicles would follow the
maintenance road east to the construction staging area. There would be no road closures or
alterations to Jamboree Road during construction and all construction equipment would be stored
in active grading areas and/or the proposed staging areas within the project area. Once
constructed, the proposed project does not include any uses or design features that would result in
interference with any adopted emergency response plan or emergency evacuation plan. The
design of the proposed project would provide adequate emergency access consistent with City
requirements, including public access trails within the project site. Therefore, the proposed
project would not result in impacts to emergency access during construction and/or operation.
The proposed project would not impair implementation of or physically interfere with an adopted
emergency response plan or emergency evacuation plan and, thus, the project would result in no
impact.
h) Expose people or structures to a significant risk of loss, injury or death involving
wildland fires, including where wildlands are adjacent to urbanized areas or where
residences are intermixed with wildlands?
No Impact. The project site is not located in an area classified as a “Wildland Area That May
Contain Substantial Forest Fire Risks and Hazards” or a “Very High Fire Hazard Severity Zone”
by the California Department of Forestry and Fire Protection (CAL FIRE 2011). Therefore, the
risk for wildland fire hazards is low, and project implementation would result in no impact to
people or structures to a significant fire risk.
Resources
California Department of Forestry and Fire Prevention. CAL FIRE: Newport Beach LRA Map.
October 2011.
City of Newport Beach, City of Newport Beach General Plan, Chapter 11: Safety Element.
Adopted July 25, 2006.
John Wayne Airport, Orange County. Airport Land Use Commission.
<http://www.ocair.com/commissions/aluc/>. Accessed on January 19, 2016.
Newport Beach Fire Department. City of Newport Beach Emergency Operations Plan, Approved
September 27, 2011.
Orange County Public and Private Airports, California. Website:<http://www.tollfreeairline.com/
california/orange.htm>. Accessed on January 19, 2016.
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3. Environmental Checklist
3.9 Hydrology and Water Quality
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
9. HYDROLOGY AND WATER QUALITY —
Would the project:
a) Violate any water quality standards or waste
discharge requirements?
b) Substantially deplete groundwater supplies or
interfere substantially with groundwater recharge such
that there would be a net deficit in aquifer volume or a
lowering of the local groundwater table level (e.g., the
production rate of pre-existing nearby wells would
drop to a level which would not support existing land
uses or planned uses for which permits have been
granted)?
c) Substantially alter the existing drainage pattern of a
site or area through the alteration of the course of a
stream or river, or by other means, in a manner that
would result in substantial erosion or siltation on- or
off-site?
d) Substantially alter the existing drainage pattern of a site
or area through the alteration of the course of a stream
or river, or by other means, substantially increase the
rate or amount of surface runoff in a manner that would
result in flooding on- or off-site?
e) Create or contribute runoff water which would exceed
the capacity of existing or planned stormwater
drainage systems or provide substantial additional
sources of polluted runoff?
f) Otherwise substantially degrade water quality?
g) Place housing within a 100-year flood hazard area as
mapped on a federal Flood Hazard Boundary or Flood
Insurance Rate Map or other flood hazard delineation
map?
h) Place within a 100-year flood hazard area structures
that would impede or redirect flood flows?
i) Expose people or structures to a significant risk of
loss, injury or death involving flooding, including
flooding as a result of the failure of a levee or dam?
j) Expose people or structures to a significant risk of
loss, injury or death involving inundation by seiche,
tsunami, or mudflow?
Discussion
a) Violate any water quality standards or waste discharge requirements?
No Impact. The proposed project would not violate any water quality standards or waste
discharge requirements because the project includes treatment facilities that would improve
surface water quality in the project area.
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3. Environmental Checklist
b) Substantially deplete groundwater supplies or interfere substantially with
groundwater recharge such that there would be a net deficit in aquifer volume or a
lowering of the local groundwater table level (e.g., the production rate of pre-
existing nearby wells would drop to a level which would not support existing land
uses or planned uses for which permits have been granted)?
Less than Significant Impact. Groundwater would be not required for construction or operation
of the proposed project. Surface seeps along the creek bank immediately upstream and
downstream of the culvert under Jamboree Road would be collected and diverted to the sanitary
sewer due to the high selenium concentrations measured in these seeps. The collection and
diversion of the significant source of selenium to the creek would measurably reduce downstream
selenium concentrations and improve water quality through the creek segment that runs through
the Big Canyon Preserve. This would allow for successful restoration efforts associated with the
proposed project The estimated seepage flows are anticipated to be less than 10% of the total
current dry weather flows in Big Canyon Creek. Therefore, approximately 90% of the current dry
weather flows would be returned to the creek. Diverting the high selenium seepage flows would
substantially reduce in-stream selenium concentrations in the downstream creek flowing through
the restoration area. Because the project would not require the use of groundwater and the project
would divert the current high selenium from seepage flows, the project would result in less than
significant impacts on groundwater supplies.
c) Substantially alter the existing drainage pattern of area, including through the
alteration of the course of a stream or river, in a manner which would result in
substantial erosion or siltation on- or off-site?
Less than Significant Impact. The project includes creek restoration activities that would
include floodplain restoration, streambank stabilization and habitat restoration. Floodplain
restoration and streambank stabilization activities would result in flood flow attenuation,
stabilization of the north bank of the main channel, and creation of an active sinous riparian
floodplain. The north creek bank at the inlet would be stabilized using natural bioengineering
techniques. Riparian habitat would be restored directly downstream of the floodplain restoration
area through the removal of invasive trees, soil remediation to reduce plant-limiting sodium
levels, and replacement with native riparian species. The proposed project would reduce the
potential for erosion and siltation to less than significant.
d) Substantially alter the existing drainage pattern of the site or area, including
through the alteration of the course of a stream or river, or substantially increase
the rate or amount of surface runoff in a manner which would result in flooding on-
or off-site?
Less than Significant Impact. The additional impervious surfaces or other similar features are
not substantial to cause any noticeable increase in surface runoff. Furthermore, the project
includes the construction of a water quality treatment bioretention cell that would treat wet-
weather flows from Jamboree Road. In order to treating the pollutants, stormwater flows from
Jamboree that currently discharge directly into the riparian creek corridor, would be directed to
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3. Environmental Checklist
the bioretention cell that would retain and filter these flows. Following treatment of the
stormwater, the flow would be discharged through an outlet structure that would control the rate
of discharge. Therefore peak storm flows that can impact downstream sections of the creek would
be attenuated. The proposed project would therefore reduce peak flows that may impact the
sensitive habitat of the site, and potential flooding impacts associated with the project would be
less than significant.
e) Create or contribute runoff water which would exceed the capacity of existing or
planned stormwater drainage systems or provide substantial additional sources of
polluted runoff?
No Impact. Surface flow rates that currently discharge to the site from Jamboree Road would be
measurably reduced by the bioretention cell. The project includes a new permanent access that
would include adequately design stormwater drainage features to accommodate the proposed
flows and not impact downstream areas. In addition, the project would not add additional sources
of polluted runoff, but would improve downstream surface water quality through the
implementation of the proposed surface water quality improvements. The proposed project would
result in no impacts to the capacity of the existing stormwater drainage system and no impacts to
downstream surface water quality.
f) Otherwise substantially degrade water quality?
No Impact. The Project would result in positive water quality improvement for both stormwater
and dry weather surface flows.
Storm Flows – The purpose of the stormwater treatment system is to reduce transportation-
related constituent concentrations currently discharged to Big Canyon Creek during storm events
and to attenuate stormwater peak-flow discharge rates from the contributing Jamboree Road
drainage area. The transportation-related pollutants are currently conveyed to the receiving waters
in Big Canyon Creek from a variety of sources, including vehicles, road maintenance,
maintenance facility runoff, and landscaping maintenance. Vehicles are known to produce a
variety of pollutants that can have a negative impact on water quality in the receiving waters to
which they drain. Metals such as copper and zinc can build up on road surfaces through brake and
tire wear; other metals such as cadmium, chromium and sometimes lead can be deposited on road
surfaces from paint on vehicles and streets. Metals often bind to sediments, trash, and debris on
road surfaces; these can be carried into waterways during storm events. In addition to pollutants
associated with vehicles, landscaped areas associated with or adjacent to streets (e.g., median,
parkway, and residential landscaping) can be sources of pollutants such as pesticides, nutrients
(particularly nitrate and phosphorus), and fecal-indicator bacteria (all of which are known to be
associated with urban landscaping, which is found throughout the 11.1-acre Jamboree Road
drainage area). These pollutants can be transported to receiving waters during storm events.
Finally, in addition to direct deposition to the road surface, street surfaces and adjacent walkways
and landscaped areas can be impacted from vehicle emissions through atmospheric deposition of
pollutants such as the dissolved fraction of metals and organics (e.g., polynuclear aromatic
hydrocarbons (PAHs).
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3. Environmental Checklist
According to national and regional best management practices (BMPs) manuals (e.g., the
California Stormwater Quality Association BMP handbook), the technology proposed in the
stormwater treatment system has been shown to be effective in treating a variety of pollutants
associated with transportation runoff, including trash, sediment (and attached pollutants),
nutrients and organics such as PAHs and pesticides, and fecal-indicator bacteria. The stormwater
treatment system would consist of a primary stormwater treatment structure and a bioretention
cell, as described below.
Dry Weather Flows The purpose of the dry weather flow diversion is to limit the contact
between dry weather flows with low selenium concentrations with groundwater seepage flows
that contain much higher selenium concentrations. Surface seeps would be passively collected
and diverted to the sanitary sewer. The lower concentration dry weather flows would be diverted
around the higher selenium seeps and back into the creek channel. Selenium reductions of 70-
90% are anticipated in downstream flows. These reductions would allow for successful and
sustainable restoration of the creek as part of the proposed project and in potential future
downstream restoration efforts.
Overview With the implementation of the proposed project, surface and groundwater quality
would not be impacted.
g) Place housing within a 100-year flood hazard area as mapped on a federal Flood
Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation
map?
No Impact. All residential properties are on the high banks above the 100-year floodplain. These
banks would not be impacted by the proposed project.
h) Place within a 100-year flood hazard area structures which would impede or
redirect flood flows?
Less than Significant Impact. One-Hundred year flows from Big Canyon Creek would be
directed through the restored creek section and the downstream stream channels. This proposed
project would improve surface water hydrology by reducing peak flows from Jamboree Road that
would be directed through the proposed bioretention cell. The currently incised creek channel
downstream of the culvert would be restored to include a wider floodplain and the northern bank
stabilized using bio-engineering techniques. The extended culvert element to accommodate the
new access road includes the implementation of concrete stilling basin and grade control structure
to dissipate storm flows and reduce the potential for downstream erosion. The planned restoration
would include removal of invasive plants and re-vegetation with native plants that would also
improve overall hydrology. The implementation of the proposed facilities on the project site
would result in less than significant impacts associated with a 100-year flood hazard area.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-46 ESA / Project No. 130934
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3. Environmental Checklist
i) Expose people or structures to a significant risk of loss, injury or death involving
flooding, including flooding as a result of the failure of a levee or dam?
No Impact. No risk associated with property loss or life threatening conditions would result from
the proposed project as no significant changes in site hydrology would occur as a result of the
project. Hydraulic analysis of the proposed flood control conveyance show that velocities in the
conveyance would be below erosive levels due to the 2% longitudinal slope and heavily vegetated
side slopes. The proposed project would not increase the risk of people or structures to loss,
injury or death involving flooding, including flooding as a result of the failure of a levee or dam.
The watershed is heavily urbanized and the Upper Newport Bay is protected against ocean waves.
Therefore, the proposed project would result in no impacts related to flooding.
j) Expose people or structures to a significant risk of loss, injury or death involving
inundation by seiche, tsunami, or mudflow?
No Impact. No risk associated with property loss or life threatening conditions would result from
the proposed project as no significant changes in site hydrology would occur as a result of the
project. Hydraulic analysis of the proposed flood control conveyance show that velocities in the
conveyance would be below erosive levels due to the 2% longitudinal slope and heavily vegetated
side slopes. The proposed project would not increase the risk of the project area or surrounding
land to be inundated as a result of seiche, tsunami, or mudflow. The watershed is heavily
urbanized and the Upper Newport Bay is protected against ocean waves. Therefore, the proposed
project would result in no impacts related to seiche, tsunami or mudflow.
Resources
California Stormwater Quality Association, Stormwater Best Management Practice Handbook,
New Development and Redevelopment, January 2003. Website:
https://www.casqa.org/sites/default/files/BMPHandbooks/BMP_NewDevRedev_Complete.
pdf. Accessed on February 12, 2016.
City of Newport Beach, City of Newport Beach General Plan, Chapter 11: Safety Element.
Adopted July 25, 2006.
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3.10 Land Use and Planning
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
10. LAND USE AND LAND USE PLANNING —
Would the project:
a) Physically divide an established community?
b) Conflict with any applicable land use plan, policy, or
regulation of an agency with jurisdiction over the
project (including, but not limited to the general plan,
specific plan, local coastal program, or zoning
ordinance) adopted for the purpose of avoiding or
mitigating an environmental effect?
c) Conflict with any applicable habitat conservation plan
or natural community conservation plan?
Discussion
a) Physically divide an established community?
No Impact. The project site is located between two residential communities to the north and
south of the project site. Creek restoration activities confined within the project site would
enhance the vegetation and habitat of the creek, and would not physically divide the existing
communities to the north and south. Thus, implementation of the project would result in no
impacts to the physical division of an established community.
b) Conflict with any applicable land use plan, policy, or regulation of an agency with
jurisdiction over the project (including, but not limited to the general plan, specific
plan, local coastal program, or zoning ordinance) adopted for the purpose of
avoiding or mitigating an environmental effect?
No Impact. The proposed project is consistent with the existing City of Newport Beach General
Plan land use and zoning designations. The project site is zoned as Open Space (OS) within the
City’s General Plan, Zoning Ordinance, and Local Coastal Program (City of Newport Beach
2010). The OS land use and zoning designation is intended to provide areas for a range of public
and private uses to “protect, maintain, and enhance the community’s natural resources.” Since the
project aims to restore natural habitat and improve water quality in the creek, the project’s
objectives align with applicable land use plans regarding OS. The project will not conflict with
any applicable land use plans, therefore, the project would result in no impacts to existing land
use plans, policies or regulations.
c) Conflict with any applicable habitat conservation plan or natural communities
conservation plan?
No Impact. The project would not conflict with the protection of biological resources under the
City of Newport Beach Municipal Code, or the City’s proposed LCP Coastal Land Use Plan
(2015 revised submittal). The proposed project, while not currently included in the Orange
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County Central-Coastal NCCP/HCP, will be designated to meet Plan standards. The highly
degraded riparian channel, floodplain, and native vegetation will be restored to better functioning
riparian habitat; restoration of adjacent coastal sage scrub areas will provide higher-quality
upland habitat for wildlife and wetland buffer function; and the water quality facilities will
greatly improve the hydrology and water quality of the creek. Therefore, the project will not
conflict with the provisions of any local policies or ordinances protecting biological resources or
any NCCP/HCPs.
Resources
City of Newport Beach, City of Newport Beach General Plan, Chapter 3: Land Use Element.
Adopted July 25, 2006
City of Newport Beach, Local Coastal Program, Coastal Land Use Plan, Amended February
2009. Website:
http://www.newportbeachca.gov/PLN/LCP/Internet%20PDFs//CLUP_Cover%20and%20T
able%20of%20Contents.pdf. Accessed on February 12, 2016.
City of Newport Beach. Newport Beach Municipal Code. Title 20: Planning and Zoning. Passed
November 24, 2015. <http://www.codepublishing.com/CA/NewportBeach/
?NewportBeach20/NewportBeach20.html>. Accessed on January 14, 2015.
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3.11 Mineral Resources
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
11. MINERAL RESOURCES — Would the project:
a) Result in the loss of availability of a known mineral
resource that would be of value to the region and the
residents of the state?
b) Result in the loss of availability of a locally important
mineral resource recovery site delineated on a local
general plan, specific plan or other land use plan?
Discussion
a) Result in the loss of availability of a known mineral resource that would be of value
to the region and the residents of the State?
No Impact. Based on the guidelines adopted by the California Geological Survey (CGS), areas
known as Mineral Resource Zones (MRZ) are classified according to the presence or absence of
significant mineral resource deposits. The City is required to respond to mineral resource
recovery areas that have been designated by the State as MRZ-2 (significant existing or likely
mineral deposits). These classifications indicate the potential for a specific area to contain
significant mineral resources.
According to the CGS, the City of Newport Beach does not contain any land classified as MRZ-2.
The project site is located on land classified as MRZ-1, which are “areas where adequate geologic
information indicates that no significant mineral deposits are present, or where it is judged that
little likelihood exists for their presence” (Division of Mines and Geology). The project involves
restoration and revegetation of the creek, and no mining operations would occur. Therefore, the
proposed project would result in no loss of availability of known mineral resources valuable to
the region or residents of the State, and no impact would occur.
b) Result in the loss of availability of a locally-important mineral resource recovery site
delineated on a local general plan, specific plan or other land use plan?
No Impact. As discussed in the 3.11a), the lack of impacts to known mineral resources that
would be of value to the region or residents of the State applies equally to locally important
mineral resource recovery sites. The City of Newport Beach General Plan classifies no land with
locally-important mineral resource deposits within the City. Therefore, the proposed project
would result in no loss of availability of a locally-important mineral resource recovery site
delineated by any land use plan, and no impact would occur.
Resources
Department of Conservation. Division of Mines and Geology. Guidelines for Classification and
Designation of Mineral Lands.
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City of Newport Beach, City of Newport Beach General Plan EIR. Mineral Resources. July 25,
2006.
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3.12 Noise
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
12. NOISE — Would the project:
a) Result in exposure of persons to, or generation of,
noise levels in excess of standards established in the
local general plan or noise ordinance, or applicable
standards of other agencies?
b) Result in exposure of persons to, or generation of,
excessive groundborne vibration or groundborne
noise levels?
c) Result in a substantial permanent increase in ambient
noise levels in the project vicinity above levels existing
without the project?
d) Result in a substantial temporary or periodic increase
in ambient noise levels in the project vicinity above
levels existing without the project?
e) For a project located within an airport land use plan
area, or, where such a plan has not been adopted, in
an area within two miles of a public airport or public
use airport, would the project expose people residing
or working in the area to excessive noise levels?
f) For a project located in the vicinity of a private airstrip,
would the project expose people residing or working in
the project area to excessive noise levels?
Discussion
Noise is generally defined as unwanted sound. Sound, traveling in the form of waves from a
source, exerts a sound pressure level (referred to as sound level) that is measured in decibels (dB),
which is the standard unit of sound amplitude measurement. The dB scale is a logarithmic scale
that describes the physical intensity of the pressure vibrations that make up any sound, with 0 dB
corresponding roughly to the threshold of human hearing and 120 to 140 dB corresponding to the
threshold of pain. Pressure waves traveling through air exert a force registered by the human ear
as sound.
Sound pressure fluctuations can be measured in units of hertz (Hz), which correspond to the
frequency of a particular sound. Typically, sound does not consist of a single frequency, but
rather a broad band of frequencies varying in levels of magnitude. When all the audible
frequencies of a sound are measured, a sound spectrum is plotted consisting of a range of
frequency spanning 20 to 20,000 Hz. The sound pressure level, therefore, constitutes the additive
force exerted by a sound corresponding to the sound frequency/sound power level spectrum.
The typical human ear is not equally sensitive to all frequencies of the audible sound spectrum.
As a consequence, when assessing potential noise impacts, sound is measured using an electronic
filter that deemphasizes the frequencies below 1,000 Hz and above 5,000 Hz in a manner
corresponding to the human ear’s decreased sensitivity to extremely low and extremely high
frequencies. This method of frequency weighting is referred to as A-weighting and is expressed
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in units of A-weighted decibels (dBA). A-weighting follows an international standard
methodology of frequency deemphasis and is typically applied to community noise
measurements.
An individual’s noise exposure is a measure of noise over a period of time. While a noise level is
a measure of noise at a given instant in time, community noise varies continuously over a period
of time with respect to the contributing sound sources of the community noise environment.
Community noise is primarily the product of many distant noise sources, which constitute a
relatively stable background noise exposure, with the individual contributors unidentifiable. The
background noise level changes throughout a typical day, but does so gradually, corresponding
with the addition and subtraction of distant noise sources such as traffic. What makes community
noise variable throughout a day, besides the slowly changing background noise, is the addition of
short-duration, single-event noise sources (e.g., aircraft flyovers, motor vehicles, sirens), which
are readily identifiable to the individual.
These successive additions of sound to the community noise environment change the community
noise level from instant to instant, requiring the measurement of noise exposure over a period of
time to legitimately characterize a community noise environment and evaluate cumulative noise
impacts. This time-varying characteristic of environmental noise is described using statistical
noise descriptors. The most frequently used noise descriptors are summarized below:
Leq: The Leq, or equivalent sound level, is the energy-mean dBA during a measured time
interval. It is the “equivalent” constant sound level that would have to be produced by a
given source to equal the acoustic energy contained in the fluctuating sound level
measured.
Lmax: The maximum, instantaneous noise level experienced during a given period of time.
Lmin: The minimum, instantaneous noise level experienced during a given period of time.
Ldn: Also termed the DNL, the Ldn is defined as the A-weighted average sound level for a 24-
hour day with a 10-dB penalty added to nighttime sound levels (10:00 p.m. to 7:00 a.m.)
to compensate for increased sensitivity to noise during usually quieter evening and
nighttime hours.
CNEL: CNEL, or Community Noise Equivalent Level, is defined as the A-weighted average
sound level for a 24-hour day. It is calculated by adding a 5-dB penalty to sound levels in
the evening (7:00 p.m. to 10:00 p.m.) and a 10-dB penalty to sound levels at night (10:00
p.m. to 7:00 a.m.) to compensate for increased sensitivity during such time periods when
a quiet environment is expected.
An important way of predicting a human reaction to a new noise environment is the way it
compares to the existing environment to which one has adapted (i.e., comparison to the ambient
noise environment). In general, the more a new noise level exceeds the previously existing
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ambient noise level, the less acceptable the new noise level would be judged by those hearing it.
With regard to increases in A-weighted noise level, the following relationships generally occur:
• Except in carefully controlled laboratory experiments, a change of 1 dBA cannot be
perceived;
• Outside of the laboratory, a 3 dBA change in noise levels is considered to be a barely
perceivable difference;
• A change in noise levels of 5 dBA is considered to be a readily perceivable difference;
and
• A change in noise levels of 10 dBA is subjectively heard as doubling of the perceived
loudness.
These relationships occur in part because of the logarithmic nature of sound and the decibel
system. The human ear perceives sound in a non-linear fashion, hence the decibel scale was
developed. Because the decibel scale is based on logarithms, two noise sources do not combine in
a simple additive fashion, but rather logarithmically. For example, if two identical noise sources
produce noise levels of 50 dBA, the combined sound level would be 53 dBA, not 100 dBA.
Noise levels from a particular source generally decline as distance to the receptor increases. Other
factors, such as the weather and reflecting or barriers, also help intensify or reduce the noise level
at any given location. A commonly used rule of thumb for roadway noise is that for every
doubling of distance from the source, the noise level is reduced by about 3 dBA at acoustically
“hard” locations (i.e., the area between the noise source and the receptor is nearly complete
asphalt, concrete, hard-packed soil, or other solid materials) and 4.5 dBA at acoustically “soft”
locations (i.e., the area between the source and receptor is normal earth or has vegetation,
including grass). Noise from stationary or point sources is reduced by about 6 to 7.5 dBA for
every doubling of distance at acoustically hard and soft locations, respectively. Noise levels may
also be reduced by intervening structures – generally, a single row of buildings between the
receptor and the noise source reduces the noise level by about 5 dBA, while a solid wall or berm
reduces noise levels by 5 to 10 dBA.
Regulatory Framework
It should be noted that the project does not include any permanent noise sources after the
completion other than periodical maintenance.
City of Newport Beach General Plan
Policy N1.8 describes significant noise impacts as below:
Require the employment of noise mitigation measures for existing sensitive uses when a
significant noise impact is identified. A significant noise impact occurs when there is an
increase in the ambient CNEL produced by new development impacting existing
sensitive uses. The CNEL increase is shown in Table 1.
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TABLE 3-10
GENELAN PLAN POLICY N1.8 DBA INCREASE
Existing CNEL
(dBA) dBA Increase
55 3
60 2
65 1
70 1
75+ Any increase is considered significant
SOURCE: City of Newport Beach General Plan
Policy N5.1 describes that the limited hours of construction activity is enforced. The limited
construction hours are based on the municipal code.
City of Newport Beach Municipal Code
Section 10.28.040 limits construction hours between 7:00 a.m. and 6:30 p.m. on any weekdays
and between 8:00 a.m. and 6:00 p.m. on any Saturdays. It also prohibits construction activities on
any Sundays and any federal holidays.
a) Exposure of persons to or generation of noise levelS in excess of standards
established in the local general plan or noise ordinance, or applicable standards or
other agencies?
Less than Significant Impact. A significant impact may occur if the proposed project would
generate excessive noise that exceeds the noise level standards set forth in the respective General
Plan Noise Elements and Noise Ordinances of the City of Newport Beach. Potential project noise
impacts were assessed for 1) project construction to the adjacent noise sensitive receivers, 2) off-
site noise impacts due to the project operation, and 3) on-site noise impact to the project site. It is
concluded the impact would be less than significant. See details below.
Construction Noise
With regard to construction noise, the City’s noise ordinance, Section 10.28.040 limits
construction hours between 7:00 a.m. and 6:30 p.m. on any weekdays and between 8:00 a.m. and
6:00 p.m. on any Saturdays. It also prohibits construction activities on any Sundays and any
federal holidays. It is assumed that construction would not occur outside of indicated hours and
considered less than significant.
Off-Site Noise
After the completion of the project, there would be no noise generated sources in the project site.
The potential noise generated activities would be occasional maintenance and repair activities
throughout a year. It is assumed that maintenance and repair activities would occur within the
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hours indicated in the City’s noise ordinance, Section 10.28.040. Therefore, the impact would be
less than significant.
On-Site Noise
The project site is identified as )pen Space in the City’s General Plan, and it would remain as
Open Space after the completion of the project. The City’s General Plan Noise Element Policy
N1.8, describes the threshold of significant impact based on the increase of noise levels over the
existing noise levels. Since the ambient noise in the vicinity of the project site would remain
unchanged after the completion of the project, the impact would be less than significant.
b) Exposure of people to generation or excessive groundborne vibration or
groundborne noise levels?
Less than Significant with Mitigation Incorporation. Ground-borne vibration would be
generated from the operation of heavy construction equipment at the project site, which could
potentially affect the existing sensitive land uses surrounding the site. Once completed, there
would be no operational sources causing ground-borne vibration.
The closest off-site structure to the project construction area is the multi-family residential
structure to the north adjacent to Jamboree Road. The distance to this structure is approximately
10 feet from potential construction equipment.
Ground-borne vibration levels resulting from construction activities at the project site were
estimated using data published by the Federal Transit Administration (FTA) in its Transit Noise
and Vibration Impact Assessment (2006) document. The FTA has adopted vibration standards
that are used to evaluate potential building damage impacts related to construction activities,
which are shown in Table 3-11.
TABLE 3-11
CONSTRUCTION VIBRATION DAMAGE CRITERIA
Building Category PPV (in/sec)
I. Reinforced-concrete, steel or timber (no plaster) 0.5
II. Engineered concrete and masonry (no plaster) 0.3
III. Non-engineered timber and masonry buildings 0.2
IV. Buildings extremely susceptible to vibration damage 0.12
SOURCE: FTA, 2006.
In addition, the FTA has also adopted standards associated with human annoyance for ground-
borne vibration impacts for the following three land-use categories: Vibration Category 1 – High
Sensitivity, Vibration Category 2 – Residential, and Vibration Category 3 – Institutional. The
FTA defines Category 1 as buildings where vibration would interfere with operations within the
building, including vibration-sensitive research and manufacturing facilities, hospitals with
vibration-sensitive equipment, and university research operations. Vibration-sensitive equipment
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includes, but is not limited to, electron microscopes, high-resolution lithographic equipment, and
normal optical microscopes. Category 2 refers to all residential land uses and any buildings where
people sleep, such as hotels and hospitals. Category 3 refers to institutional land uses such as
schools, churches, other institutions, and quiet offices that do not have vibration-sensitive
equipment, but still have the potential for activity interference. The vibration thresholds
associated with human annoyance for these three land-use categories are shown in Table 3-12.
TABLE 3-12
GROUNDBORNE VIBRATION IMPACT CRITERIA FOR GENERAL ASSESSMENT
Land Use Category Frequent Eventsa
Occasional
Eventsb Infrequent Eventsc
Category 1: Buildings where vibration would
interfere with interior operations.
65 VdBd 65 VdBd 65 VdBd
Category 2: Residences and buildings where
people normally sleep.
72 VdB 75 VdB 80 VdB
Category 3: Institutional land uses with
primarily daytime use.
75 VdB 78 VdB 83 VdB
a “Frequent Events” is defined as more than 70 vibration events of the same source per day.
b “Occasional Events” is defined as between 30 and 70 vibration events of the same source per day.
c “Infrequent Events” is defined as fewer than 30 vibration events of the same kind per day.
d This criterion is based on levels that are acceptable for most moderately sensitive equipment such as optical microscopes.
SOURCE: FTA, 2006.
The various peak particle velocity (PPV) expressed in inches per second (in/sec) and root mean
square (RMS) velocity expressed in VdB levels for the general construction equipment that
would operate during the construction of the proposed project are identified in Table 3-13. Note
that it is assumed that impact activities, such as pile driving, would not be used for this project.
TABLE 3-13
VIBRATION SOURCE LEVELS FOR CONSTRUCTION EQUIPMENT
Equipment
Approximate PPV
(in/sec) at 25 feet
Approximate RMS
(VdB) at 25 feet
Large Bulldozer 0.089 87
Loaded Trucks 0.076 86
Jackhammer 0.035 79
Small Bulldozer 0.003 58
1 Vibratory roller would be used only for Pond Lining/Miscellaneous phase.
SOURCE: FTA, 2006.
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Structure Damage
Construction activities associated with the proposed project would have the potential to impact
the surrounding off-site structures. The closest multi-family residential structure to the north is
considered as non-engineered timber structure and is located approximately 10 feet from
construction equipment. Therefore, the vibration impact threshold would be 0.2 in/sec PPV. The
PPV value of a large bulldozer at 10 feet would be 0.352 in/sec PPV, which exceeds the impact
threshold. This exceedance of the vibration level threshold for structural damage would be
considered significant.
Mitigation Measure
NOI-1: Large construction equipment, such as large bulldozer and loaded trucks, shall be
replaced with smaller equipment when the construction equipment is within 45 feet of the
residential structure.
Significance after Mitigation
With the implementation of Mitigation Measure MM NOI-1, vibration impacts causing structural
damage from construction activities would be less than significant. When a small bulldozer is
used, the PPV value at 10 feet would be 0.119 in/sec PPV, which would be less than the impact
threshold of 0.2 in/sec PPV.
Human Annoyance
The construction vibration could annoy people within a building. The vibration impact threshold
for human annoyance at a residential structure would be 80 VdB. The RMS value of a large
bulldozer at 10 feet would be 99 VdB which would exceed the human annoyance vibration
threshold of 80 VdB. Therefore, the project construction activities could result in significant
human annoyance vibration impacts.
Mitigation Measure
Implementation of Mitigation Measure NOI-1 is required.
Significance after Mitigation
With the implementation of Mitigation Measure MM NOI-1, vibration impacts causing human
annoyance would be reduce to less than significant. The use of a small bulldozer would result in a
RMS value at 10 feet of 70 VdB, which would be less than the impact threshold of 80 VdB.
Operation
Once construction activities have been completed, the potential vibration activities would occur
when occasional maintenance is conducted by a large piece of equipment. Since the specific
equipment is unknown, the potential impact could be considered significant.
Mitigation Measure
Implementation of Mitigation Measure NOI-1 is required.
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Significance after Mitigation
With the implementation of Mitigation Measure NOI-1, vibration impacts from operational
activities associated with maintenance would be reduce to less than significant.
c) A substantial permanent increase in ambient noise levels in the project vicinity
above levels existing without the project?
Less than Significant Impact. After the completion of the project, there would be no noise
generated sources in the project site. The potential noise generated activities would be occasional
maintenance and repair activities throughout a year. It is assumed that maintenance and repair
activities would occur within the hours indicated in the City’s noise ordinance, Section 10.28.040.
Therefore, the impact would be less than significant.
d) A substantial temporary or periodic increase in ambient noise levels in the project
vicinity above levels existing without the project?
Less than Significant with Mitigation Incorporation. The project would temporary increase
noise levels during construction phases. Construction of the proposed project would occur in
multiple phases within a project boundary and is expected to last approximately five months.
Construction phases and activities are presented in Table 3-14.
TABLE 3-14
CONSTRUCTION SCHEDULE
Phase Activity Duration Months
Mobilization & Earthwork
Site preparation/
clearing/Grubbing 1-2 weeks Month 1
Excavation and grading 2-3 weeks Months 1 and 2
Drainage Structures and
Piping Construction
Culvert extension 4-6 weeks Months 2 and 3
Dry weather diversion structures and
external piping 2-3 weeks Month 3
Water Quality System
Construction
Bioretention cell liner and piling 1-2 weeks Months 3 and 4
Bioretention cell media placement 1-2 weeks Month 4
Bioengineering structure construction 1-2 weeks Month 4
OCSD Scope OCSD dosing station installation 4-6 weeks Months 3, 4, and 5
Restoration Site vegetation restoration 3-4 weeks Month 5
Construction activities occurring under each of these phases would require the use of heavy
equipment (e.g., excavators, backhoes, loaders, tractors, etc.) along with the use of smaller power
tools, generators, and other sources of noise. During each construction phase there would be a
different mix of equipment operating and noise levels would vary based on the amount of
equipment in operation and the location of each activity. As such, construction activity noise
levels during each phase would fluctuate depending on the particular type, number, and duration
of use of the various pieces of construction equipment.
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Table 3-15 includes the list of construction equipment with quantity, usage per day, and
estimated noise levels per phase. It should be noted that maximum noise levels associated with
the construction equipment would only be generated when the equipment are operated at full
power. Typically, the operating cycle for a piece of construction equipment would involve one or
two minutes of full power operation followed by three or four minutes at lower power settings.
As such, the maximum noise levels shown in Table 3-15 would only occur occasionally
throughout the construction day.
In addition to Table 3-15, hauling trucks would access the project site from Back Bay Drive and
an access road through Big Canyon. Trucks would be very slow. However, trucks would be
passing by within 100 feet of existing multi-family residential homes.
TABLE 3-15
CONSTRUCTION EQUIPMENT USAGE AND NOISE LEVELS
Equipmenta Maximum Noise
Level at 50' (dBA)b
Equipment
Quantitya Hours
per daya Estimated Noise
Level at 50’ (dBA)
Site Preparation Clearing and Grubbing
Loader 80 1 8 90
Back Hoe 80 1 8
Dozer 85 1 8
Chipper (mulch) 85 1 8
Haul Truck 84 2 8
Water Truck 84 1 2
Excavation and Grading
Back Hoe 80 1 8 89
Dozer 85 1 8
Compactor 80 1 8
Haul Truck 84 2 8
Water Truck 84 1 2
Culvert Extension
Loader 80 1 8 83
Back Hoe 80 1 8
Water Truck 84 1 2
Dry Weather Diversion Structures and External Piping
Back Hoe 80 1 8 78
Bioretention Cell Liner and Piping
Loader 80 1 8 82
Water Truck 84 1 2
Mini Excavator 85 1 2
Bioretention Cell Media Placement
Loader 80 1 8 81
Water Truck 84 1 2
Bioengineering Structure Construction
Loader 80 1 8 81
Water Truck 84 1 2
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TABLE 3-15
CONSTRUCTION EQUIPMENT USAGE AND NOISE LEVELS
Equipmenta Maximum Noise
Level at 50' (dBA)b
Equipment
Quantitya Hours
per daya Estimated Noise
Level at 50’ (dBA)
OCSD Dosing Station Installation
Loader 80 1 8 86
Back Hoe 80 1 8
Dozer 85 1 8
Compactor 80 1 8
Site Vegetation Restoration
Dozer 85 1 8 88
Water Truck 84 1 2
Soil Disc / Tractor 84 1 8
Hydroseeder Truck 84 1 8
a Burns & McDonnell 2016. b maximum noise levels are derived from Federal Highway Administration’s (FHWA) Roadway Construction Noise
Model User’s Guide. Noise levels for those equipment not included in this User’s Guide are estimated based on
similar equipment.
SOURCE: ESA 2016.
During the project’s construction activities, the nearest and most notable off-site sensitive
receptors to the construction site would be the existing multi-family residential uses to the north,
which would be as close as 10 feet from the project boundary. Due to the use of construction
equipment during the construction phases, the project would expose these sensitive receptors to
increased exterior noise levels. Over the course of a construction day, the highest noise levels
would be generated when multiple pieces of construction equipment are being operated
concurrently.
The City’s noise ordinance, Section 10.28.040 limits construction hours to between 7:00 a.m. and
6:30 p.m. on any weekdays and between 8:00 a.m. and 6:00 p.m. on any Saturdays. It also
prohibits construction activities on any Sundays and any federal holidays. Thus, the construction
activities associated with the proposed project would be required to adhere to the applicable
permitted hours of operation established under the City of Newport Beach’s Noise Ordinance.
However, although the proposed project’s construction activities would only occur under the
permitted hours allowed under the City of Newport Beach’s Noise Ordinance, the proposed
project would still expose the existing sensitive receptors located in proximity to the project site
to increased exterior noise levels above existing ambient noise levels. It should be noted,
however, that any increase in noise levels at the off-site sensitive receptors during project
construction would be temporary in nature, and would not generate continuously high noise
levels, although occasional single-event disturbances are possible. Nonetheless, because the
temporary noise nuisance generated by the project’s construction activities would constitute a
substantial temporary or periodic increase in ambient noise levels in the project vicinity above
levels existing without the project, this noise impact is considered to be potentially significant.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-61 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
Mitigation Measures
NOI-2: The construction contractor shall ensure proper maintenance and working order of
equipment and vehicles and that all construction equipment is equipped with manufacturers
approved mufflers and baffles.
NOI-3: The construction contractor(s) shall endeavor to use quieter equipment as opposed to
noisier equipment (such as rubber-tired equipment rather than track equipment), when feasible.
Noisy equipment shall be switched off when not in use.
NOI-4: Construction activities shall be scheduled so as to avoid operating several pieces of
equipment simultaneously, which causes high noise levels, to the extent feasible.
NOI-5: The construction contractor shall place all stationary construction equipment so that
emitted noise is directed away from sensitive receptors nearest the project site.
Significance after Mitigation
Implementation of Mitigation Measures NOI-2 through NOI-5, which would require the
implementation of noise reduction devices and techniques during construction at the project site,
would reduce the noise levels associated with construction of the proposed project to the
maximum extent that is technically feasible, and this reduction would result in less than
significant noise impacts.
e) For a project located within an airport land use plan or, where such a plan has not
been adopted, within two miles of a public airport or public use airport, would the
project expose people residing or working in the project area to excessive noise
levels?
No Impact. The project site is located approximately 2.3 miles south of the John Wayne Airport.
However, the project site is not within the airport’s Noise Impact Zones, as specified by the
Airport Environs Land Use Plan (AELUP) for John Wayne Airport (ALUC, 2008). Further, the
project would not increase the amount of people living or working in the area, and would
therefore, not expose people residing or working in the area to excessive noise levels.
f) For a project within the vicinity of a private airstrip, would the project expose
people residing or working in the project area to excessive noise levels?
No Impact. There are no private airstrips in the vicinity of the proposed project. Further, the
project would not increase the amount of people living or working in the area, and would
therefore, not expose people residing or working in the area to excessive noise levels.
Resources
City of Newport Beach, City of Newport Beach General Plan. November 2006.
City of Newport Beach, City of Newport Beach Municipal Code. Passed November 2015.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-62 ESA / Project No. 130934
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3. Environmental Checklist
Federal Highway Administration (FHWA), Roadway Construction Noise Model User’s Guide,
2006.
Federal Transit Administration (FTA), Transit Noise and Vibration Impact Assessment, 2006.
County of Orange, Airport Environs Land Use Plan for John Wayne Airport, April 17, 2008.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-63 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
3.13 Population and Housing
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
13. POPULATION AND HOUSING — Would the
project:
a) Induce substantial population growth in an area, either
directly (for example, by proposing new homes and
businesses) or indirectly (for example, through
extension of roads or other infrastructure)?
b) Displace substantial numbers of existing housing
units, necessitating the construction of replacement
housing elsewhere?
c) Displace substantial numbers of people, necessitating
the construction of replacement housing elsewhere?
Discussion
a) Induce substantial population growth in an area, either directly (for example, by
proposing new homes and businesses) or indirectly (for example, through extension
of roads or other infrastructure)?
No Impact. The proposed project would not increase the number of residents within the City.
Project construction would require a total of about 8 employees per day that would be employed
temporarily during construction, and these employees would not induce population growth within
the City. The duration of the project construction would last approximately five months, and it
would not result in population growth in the area due to the project’s temporary activities lasting
only five months. Therefore, the project would result in no direct or indirect impacts to
population growth in the project vicinity.
b) Displace substantial numbers of existing housing, necessitating the construction of
replacement housing elsewhere?
No Impact. The project site is located on open space land that is a natural habitat for various
plant and wildlife species. There is no existing housing on the project site, no displacement of
existing housing and no required replacement housing. No impact would occur.
c) Displace substantial numbers of people, necessitating the construction of
replacement housing elsewhere?
No Impact. The project site is located on open space land that is utilized as a natural habitat for
various plant and wildlife species. The project would not increase the number of residents within
the City. Therefore, the project would not displace people and would not require the construction
of replacement housing. No impact would occur.
Resources
None.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-64 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
3.14 Public Services
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
14. PUBLIC SERVICES — Would the project:
a) Result in substantial adverse physical impacts
associated with the provision of, or the need for, new
or physically altered governmental facilities, the
construction of which could cause significant
environmental impacts, in order to maintain
acceptable service ratios, response times, or other
performance objectives for any of the following public
services:
i) Fire protection?
ii) Police protection?
iii) Schools?
iv) Parks?
v) Other public facilities?
Discussion
Would the project result in substantial adverse physical impacts associated with the
provision of new or physically altered governmental facilities, need for new or physically
altered governmental facilities, the construction of which could cause significant
environmental impacts, in order to maintain acceptable service ratios, response times or
other performance objectives for any of the public services:
a) Fire protection?
No Impact. The Newport Beach Fire Department (NBFD) provides fire protection services for
the entire City. The nearest NBFD fire station is Fire Station #3 located approximately 0.4 miles
south of the project site at 868 Santa Barbara Drive. The proposed project would restore habitat,
provide water quality features, and provide enhanced access to the project site for trail users. The
proposed project could increase the use of the project area by increasing access and providing
educational opportunities through the installation of interpretive signs along the trail. The project
site could also provide learning opportunities for community and school groups. Although the
project may increase the use of the project area, this increase would not result in a substantial
number of trail users such that the fire department’s service would be substantially affected. In
addition, the enhancement of onsite access would allow the fire department improved access
within the project site for emergencies. Because the proposed project is not altering the use of the
project site (i.e., provision of trails), and the project would not substantially alter the number of
trail users, the proposed project would not require the NBFD to provide new or physically altered
facilities to serve the project site. Therefore, the implementation of the proposed project would
result in no environmental impacts to new or physically altered fire department facilities because
changes to these City facilities would not be required.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-65 ESA / Project No. 130934
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3. Environmental Checklist
b) Police protection?
No Impact. The Newport Beach Police Department (NBPD) provides local police services to the
City of Newport Beach. The NBPD headquarters is located adjacent to NBFD Fire Station #3 at
870 Santa Barbara Drive. The proposed project would restore habitat, provide water quality
features, and provide enhanced access to the project site for trail users. The proposed project
could increase the use of the project area by increasing access and providing educational
opportunities through the installation of interpretive signs along the trail. The project site could
also provide learning opportunities for community and school groups. Although the project may
increase the use of the project area, this increase would not result in a substantial number of trail
users such that the police department’s service would be substantially affected. In addition, the
enhancement of onsite access would allow the police department improved access within the
project site for emergencies. Because the proposed project is not altering the use of the project
site (i.e., provision of trails) and the project would not substantially alter the number of trail users,
the proposed project would not require the NBPD to provide new or physically altered facilities
to serve the project site. Therefore, the implementation of the proposed project would result in no
environmental impacts to new or physically altered police department facilities because changes
to these City facilities would not be required.
c) Schools?
No Impact. The Newport-Mesa Unified School District (NMUSD) provides public educational
services to the City of Newport Beach, as well as the City of Costa Mesa and other
unincorporated areas of Orange County. The proposed project would not introduce new residents
within the City. Therefore, the project would not increase the demand for school facilities. As a
result, the proposed project would not require the NMUSD to provide new or physically altered
school facilities. The project would result in no environmental impacts to new or physically
altered school facilities because changes to school facilities would not be required.
d) Parks?
No Impact. The proposed project encompasses about 6 acres in the eastern portion of the 60-acre
Big Canyon Nature Park. The project site is designated as Open Space by the City General Plan,
which is intended to “provide areas for a range of public and private uses to protect, maintain, and
enhance the community’s natural resources.” The proposed project would enhance the
recreational activities in the park by providing an extension of the existing trails to allow for
pedestrian and bicycle travel. The official trail would allow access for the public to learn and
enjoy the native habitats located within the park. The project’s habitat restoration and access trails
would enhance the quality of the park. The proposed project would not require the City to provide
new or physically altered park facilities because these facilities would not be required to serve the
project. Therefore, the implementation of the proposed project would result in no environmental
impacts to new or physically altered park facilities.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-66 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
e) Other public facilities?
No Impact. The proposed project would introduce no new residents that would directly increase
the City’s population, and thus the project would result in no increase in the demand for other
public services, such as libraries or hospitals. Therefore, the implementation of the proposed
project would result in no environmental impacts to new or physically altered public facilities
such as libraries and hospitals.
Resources
City of Newport Beach, Fire Stations. Website:
http://newportbeachca.gov/government/departments/fire-department/fire-operations-
division/fire-stations. Accessed on February 12, 2016.
City of Newport Beach, City of Newport Beach General Plan. General Plan Land Use Overview
Map, November 2006. Website:
http://www.newportbeachca.gov/PLN/General_Plan/Figures/FigLU01_GeneralPlanOvervi
ewMap_11x17color_web.pdf. Accessed on February 12, 2016.
City of Newport Beach, Police Department. Website: http://www.nbpd.org/. Accessed on
February 12, 2016.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-67 ESA / Project No. 130934
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3. Environmental Checklist
3.15 Recreation
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
15. RECREATION — Would the project:
a) Increase the use of existing neighborhood and regional
parks or other recreational facilities such that
substantial physical deterioration of the facilities would
occur or be accelerated?
b) Include recreational facilities or require the
construction or expansion of recreational facilities that
might have an adverse physical effect on the
environment?
Discussion
a) Increase the use of existing neighborhood and regional parks or other recreational
facilities such that substantial physical deterioration of the facilities would occur or
be accelerated?
Less than Significant Impact. The proposed project encompasses about 6 acres in the eastern
portion of the 60-acre Big Canyon Nature Park. The proposed project would enhance the
recreational activities in the park by providing an extension of the existing trails to allow for
pedestrian and bicycle travel. The official trail would allow access for the public to learn and
enjoy the native habitats located within the park. The proposed project could increase the use of
the project area by increasing access and providing educational opportunities through the
installation of interpretive signs along the trail. The project site could also provide learning
opportunities for community and school groups. Although the project may increase the use of the
project area, this increase would not result in a substantial number of trail users such that the
existing trails would result in substantial physical deterioration. The proposed project would
result in a less than significant impact on the existing trails in the project area.
b) Include recreational facilities or require the construction or expansion of
recreational facilities that might have an adverse physical effect on the
environment?
No Impact. The proposed project includes the enhancement of recreational activities within a
portion of the existing Big Canyon Nature Park. The implementation of these enhancements
would not require additional recreational facilities to serve the project. Therefore, the project
would not result in an adverse physical effect on the environment from the construction or
expansion of additional recreational facilities because the project would not require additional
recreational facilities.
Resources
None.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-68 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
3.16 Transportation and Traffic
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
16. TRANSPORTATION AND TRAFFIC —
Would the project:
a) Conflict with an applicable plan, ordinance or policy
establishing measures of effectiveness for the
performance of the circulation system, taking into
account all modes of transportation including mass
transit and non-motorized travel and relevant
components of the circulation system, including but not
limited to intersections, streets, highways and freeways,
pedestrian and bicycle paths, and mass transit?
b) Conflict with an applicable congestion management
program, including, but not limited to, level of service
standards and travel demand measures, or other
standards established by the county congestion
management agency for designated roads or
highways?
c) Result in a change in air traffic patterns, including
either an increase in traffic levels or a change in
location, that results in substantial safety risks?
d) Substantially increase hazards due to a design feature
(e.g., sharp curves or dangerous intersections) or
incompatible uses (e.g., farm equipment)?
e) Result in inadequate emergency access?
f) Conflict with adopted policies, plans, or programs
regarding public transit, bicycle, or pedestrian
facilities, or otherwise decrease the performance or
safety of such facilities?
Discussion
a) Conflict with an applicable plan, ordinance or policy establishing measures of
effectiveness for the performance of the circulation system, taking into account all
modes of transportation including mass transit and non-motorized travel and
relevant components of the circulation system, including but not limited to
intersections, streets, highways and freeways, pedestrian and bicycle paths, and
mass transit?
Less than Significant Impact. The project site is assessable from Back Bay Drive and Jamboree
Road by trail users as well as maintenance personnel. The implementation of the proposed project
would result in an increase in traffic during construction activities and may result in minor
increases in maintenance personnel trips during the operation of the project. During construction,
approximately 8 employees will travel to the project site during the morning peak hour traffic
period (i.e., prior to 9 am). Construction activities will require the use of haul trucks for
vegetation and soil removal. The haul trucks would be used during the non-peak hours (i.e., after
9 am and prior to 4 pm). A maximum of 40 trucks per day during 6 hours each day would result
in a maximum average of 7 trucks per hour. Trucks arriving to the site would travel along
Jamboree Road, San Joaquin Hills Drive, and Back Bay Drive to the access road within Big
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-69 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
Canyon. Back Bay Drive is a one way roadway that provides northbound travel. Trucks exiting
the project site would travel along the Big Canyon access road to Back Bay Drive to East Bluff
Drive and then to Jamboree Road. The addition of 8 employee trips during the peak hour and an
average of about 7 truck trips per hour during the non-peak hours would not result in substantial
traffic effects at intersections or roadways in the project vicinity.
b) Conflict with an applicable congestion management program, including, but not
limited to, level of service standards and travel demand measures, or other
standards established by the county congestion management agency for designated
roads or highways?
Less than Significant Impact. As stated above, the proposed project would result in a minimal
amount of traffic trips to the surrounding street network. The applicable congestion management
program is administered by the Orange County Transportation Agency (OCTA). According to the
OCTA 2015 Congestion Management Program (CMP), the nearest CMP roadway is
approximately 2 miles north of the project site at Jamboree Road and State Route 73. As stated
above, the proposed project is anticipated to generate 8 employee trips during the peak hour and 7
truck trips during the non-peak hours. This level of traffic is considered minimal. According to
the CMP Preparation Manual, a traffic impact analysis (TIA) is required for CMP purposes if a
project generates 2,400 or more daily trips if the project does not directly access the CMP
Highway System link, such as the proposed project (Orange County Transportation Authority,
2011). Because the project would generate a maximum of 40 trucks entering and 40 trucks exiting
the site and up to 8 employee vehicles entering and 8 employees exiting the project site, the
project would generate substantially fewer daily trips than the 2,400 or more daily trips that
require a TIA to be prepared for CMP purposes. Therefore, the project would result in a less than
significant impact on a CMP facility.
c) Result in a change in air traffic patterns, including either an increase in traffic levels
or a change in location, that results in substantial safety risks?
No Impact. The implementation of the proposed project would include facilities that would not
affect air traffic patterns. The nearest airport to the project site is John Wayne Airport which is
located approximately 2.3 miles north of the project site.
d) Substantially increase hazards due to a design feature (e.g., sharp curves or
dangerous intersections) or incompatible uses (e.g., farm equipment)?
No Impact. The project site currently contains a maintenance access off of Jamboree Road. The
proposed project includes a modified maintenance road access that is perpendicular to Jamboree
Road. The proposed access would meet the City of Newport Beach design requirements for
maintenance roads. In addition, construction vehicles are proposed to access Back Bay Drive. The
current speed limit for vehicles on Back Bay Drive is 15 miles per hour. Construction vehicles
associated with the proposed project would limit speeds on Back Bay Drive to 15 miles per hour
to ensure traffic safety for pedestrians, bicyclists and equestrian users of the trail along Back Bay
Drive. In addition, as part of a standard City procedure during public works projects, signs will be
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-70 ESA / Project No. 130934
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3. Environmental Checklist
posted along Back Bay Drive regarding the construction activities and duration. Therefore, the
proposed project would not result in increasing hazards due to a design feature.
e) Result in inadequate emergency access?
No Impact. Project construction activities would be located on the project site and would not
require any lane closures. In addition, project operational activities will not require lane closures
or impact emergency access. The provision of additional trail segments on the project site would
provide greater access to the project area, but would not adversely affect emergency access.
Therefore, the project would not impact emergency access to the project site or areas in the
vicinity of the project site.
f) Conflict with adopted policies, plans, or programs regarding public transit, bicycle,
or pedestrian facilities, or otherwise decrease the performance or safety of such
facilities?
No Impact. The implementation of the proposed project would not conflict with policies, plans or
programs related to public transit, bicycle or pedestrian facilities. Back Bay Drive currently has
public transportation facilities, including a one way vehicular pathway. The project construction
vehicles would use the one-way vehicular pathway and limit their speeds to the existing 15 miles
per hour limit.
Resources
Orange County Transportation Authority, Congestion Management Program, 2015. Website:
http://www.octa.net/pdf/Final%202015%20CMP.pdf. Accessed on February 16, 2016.
Orange County Transportation Authority, Congestion Management Program Preparation Manual,
2011. Website: http://www.octa.net/pdf/cmpprepmanual.pdf. Accessed on February 16,
2016.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-71 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
3.17 Utilities and Service Systems
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
17. UTILITIES AND SERVICE SYSTEMS —
Would the project:
a) Conflict with wastewater treatment requirements of
the applicable Regional Water Quality Control Board?
b) Require or result in the construction of new water or
wastewater treatment facilities or expansion of
existing facilities, the construction of which could
cause significant environmental effects?
c) Require or result in the construction of new storm
water drainage facilities, or expansion of existing
facilities, the construction of which could cause
significant environmental effects?
d) Have sufficient water supplies available to serve the
project from existing entitlements and resources, or
are new or expanded entitlements needed?
e) Result in a determination by the wastewater treatment
provider that would serve the project that it has
adequate capacity to serve the project’s projected
demand in addition to the provider’s existing
commitments?
f) Be served by a landfill with sufficient permitted
capacity to accommodate the project’s solid waste
disposal needs?
g) Comply with federal, state, and local statutes and
regulations related to solid waste?
Discussion
a) Exceed wastewater treatment requirements of the applicable Regional Water
Quality Control Board?
No Impact. The Regional Water Quality Control Board, Santa Ana Region, issued a National
Pollutant Discharge Elimination System (NPDES) permit that implements federal and state law
governing point source discharges and nonpoint source discharges to surface waters of the United
States. Construction and operation of the proposed project includes a wastewater pipe that would
allow selenium-concentrated water from seeps to be conveyed to the existing wastewater pipe
located along Jamboree Road. The wastewater would be conveyed to the Orange County
Sanitation District treatment facilities. The amount and frequency of discharged selenium
wastewater would be nominal, and the proposed project would not exceed OCSD’s wastewater
treatment requirements of the Santa Ana Region of the Regional Water Quality Control Board.
Thus, the project would not impact existing wastewater treatment requirements.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-72 ESA / Project No. 130934
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3. Environmental Checklist
b) Require or result in the construction of new water or wastewater treatment facilities
or expansion of existing facilities, the construction of which could cause significant
environmental effects?
No Impact. The proposed project would not require the construction of a new water or
wastewater treatment facility or expansion of the existing treatment facilities serving the project
vicinity. The project requires no potable water supply for the project site. The project would
involve the extension of an existing sewer conveyance within the project site, but would not
require the extension of any existing water or wastewater facilities off the project site. Therefore,
the proposed project would result in no impact requiring the construction of water or wastewater
treatment facilities.
c) Require or result in the construction of new storm water drainage facilities or
expansion of existing facilities, the construction of which could cause significant
environmental effects?
No Impact. The proposed project would not require the construction of new stormwater drainage
facilities. The project itself includes the construction of a primary stormwater treatment structure
to trap and pretreat contaminants prior to conveyance to the bioretention cell. The project would
not require the addition of a storm drain conveyance or the expansion of any stormwater drainage
facilities since the project aims to restore the natural habitat and improve water quality within the
creek. With the implementation of these features, the proposed project would not require the
construction of new storm water drainage facilities or expansion of existing facilities off site.
Therefore, the project would result in no environmental effects from new storm water drainage
facilities or expansion of existing facilities to serve the proposed project.
d) Have sufficient water supplies available to serve the project from existing
entitlements and resources, or are new or expanded entitlements needed?
No Impact. The City of Newport Beach’s water supply is provided by the Municipal Water
District of Orange County. The construction and operation of the proposed project requires no use
of imported water supply from existing water resources. Thus, the project would result in no need
for new or expanded water supply entitlements, and no impacts would occur.
e) Result in a determination by the wastewater treatment provider which serves or
may serve the project that it has adequate capacity to serve the project’s projected
demand in addition to the provider’s existing commitments?
Less than Significant Impact. Wastewater collected by the Sanitary District is sent to the
County Sanitation Districts of Orange County (County Sanitation) plants for treatment and
disposal. Wastewater is treated at County Sanitation’s treatment plants in Fountain Valley and
Huntington Beach. According to County Sanitation’s treatment plant operational data, the
combined effluent treated at both plants is approximately 200 million gallons daily (average).
County Sanitation operates under an NPDES ocean discharge permit issued by the California
Regional Water Quality Control Board (OCSD, 2016). The project’s increase in selenium
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-73 ESA / Project No. 130934
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3. Environmental Checklist
wastewater would be infrequent and not be substantial. Project implementation would contribute
a nominal amount of wastewater and would not cause the treatment plants’ operating capacities to
be exceeded. Therefore, the proposed project would result in a less than significant impact to
wastewater treatment capacity.
f) Be served by a landfill with sufficient permitted capacity to accommodate the
project’s solid waste disposal needs?
Less than Significant Impact. The project site would be served by the solid waste facilities and
landfills that are operated by the Orange County Waste and Recycling (OCWR). The nearest
landfill to the project location is the Frank R. Bowerman Sanitary Landfill in Irvine, and is the
only landfill that serves the City of Newport Beach. The Bowerman Landfill is permitted as a
Class III landfill to receive a daily maximum of 11,500 tons per day. Class III landfills accept
only non-hazardous municipal solid waste for disposal; no hazardous or liquid waste can be
accepted. It is currently estimated to operate with adequate capacity until 2053. The landfill is
required to comply with numerous landfill regulations from federal, state and local regulatory
agencies (OCWR, 2016).
Project implementation would result in the need for disposal of debris from construction and
maintenance activities. Solid waste removed from the project site would include dead or non-
native vegetation. Debris would be removed with construction equipment and transported to the
landfill by haul trucks. It is anticipated that the project’s generation of solid waste would be at its
greatest during initial construction activities due to the primary removal of non-native habitat
vegetation. Thereafter, the project would result in minimal removal of dead vegetation during
operational maintenance activities. Given the project’s scale, it is anticipated that the specified
landfill would have the adequate capacity to accommodate the project’s waste disposal needs.
Therefore, the project would result in a less than significant impact to landfill capacity.
g) Comply with federal, state, and local statutes and regulations related to solid waste?
No Impact. Construction and operation of the proposed project would result in the disposal of
dead or non-native vegetation to the Frank R. Boweman Sanitary Landfill in Irvine. The disposal
of vegetation would comply with federal, state, and local statutes related to solid waste. No
impact to these regulations would occur with project implementation.
Resources
City of Newport Beach. Draft Environmental Impact Report – General Plan 2006 Update.
Volume I. April 2006.
Orange County Sanitation District. <http://www.ocsd.com/about-ocsd/general-information/
facilities>. Accessed February 3, 2016.
Orange County Waste and Recyling. <http://oclandfills.com/landfill/active/bowerman>. Accessed
February 3, 2016.
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3. Environmental Checklist
3.18 Mandatory Findings of Significance
Issues (and Supporting Information Sources):
Potentially
Significant
Impact
Less Than
Significant
with
Mitigation
Incorporation
Less Than
Significant
Impact No Impact
18. MANDATORY FINDINGS OF SIGNIFICANCE
—
Would the project:
a) Have the potential to degrade the quality of the
environment, substantially reduce the habitat of a fish
or wildlife species, cause a fish or wildlife population
to drop below self-sustaining levels, threaten to
eliminate a plant or animal community, reduce the
number or restrict the range of a rare or endangered
plant or animal, or eliminate important examples of the
major periods of California history or prehistory?
b) Have impacts that are individually limited, but
cumulatively considerable? (“Cumulatively
considerable” means that the incremental effects of a
project are considerable when viewed in connection
with the effects of past projects, the effects of other
current projects, and the effects of probable future
projects)?
c) Have environmental effects that would cause
substantial adverse effects on human beings, either
directly or indirectly?
Discussion
a) Have the potential to degrade the quality of the environment, substantially reduce
the habitat of a fish or wildlife species, cause a fish or wildlife population to drop
below self-sustaining levels, threaten to eliminate a plant or animal community,
reduce the number or restrict the range of a rare or endangered plant or animal, or
eliminate important examples of the major periods of California history or
prehistory?
Less than Significant with Mitigation Incorporated. Construction activities associated with the
proposed project could impact nesting birds, vegetation communities such as riparian and wetland
habitat and could temporarily disrupt wildlife movement. These potential impacts to these
biological resources would be significant.
Construction activities could also impact historical or prehistorical resources. Although no
resources are known to occur on the project site, there is a potential for unknown historical or
prehistorical resources to be located on the project site based on resources found in the project
vicinity. These potential unknown resources could be significantly affected.
Mitigation Measures
Implementation of Mitigation Measures BIO-1 through BIO-3, CR-1 and CR-2 is required.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-75 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
Significance after Mitigation
The implementation of Mitigation Measures BIO-1, BIO-2, and BIO-3 to reduce these potential
impacts on biological resources to less than significant.
The implementation of Mitigation Measures CR-1 and CR-2 would reduce potential impact to
historical and prehistorical resources to less than significant.
b) Have impacts that are individually limited, but cumulatively considerable?
(“Cumulatively considerable” means that the incremental effects of a project are
considerable when viewed in connection with the effects of past projects, the effects
of other current projects, and the effects of probable future projects)?
Less than Significant with Mitigation Incorporated. Based on a review of the City of Newport
Beach Cumulative Projects List, there are various projects in different planning stages that are
located within two miles of the project site; however, only one project (one new residence) that is
located upstream within Big Canyon of the project site. The various projects include an
Autonation (about 2.0 miles from the site), Environmental Nature Center Preschool (about 1.7
miles from the site), condominium development at Newport Center Villas (about 1.0 mile from
the site), mixed-use development at Back Bay Landing (about 1.5 miles from the site), Balboa
Marina expansion (about 1.7 miles from the site), medical offices (about 1.7 miles from the site),
a residence (about 0.4 mile from the site), construction of a clubhouse at Newport Beach Country
Club (about 1.0 miles from the site), condominium units (about 0.6 mile from the site), and a
commercial development (about 2.0 mile from the site).
As discussed in Section 3 of this IS/MND, the proposed project would result in significant
impacts to biological resources, cultural resources, vibration, and construction noise. The project
would substantially contribute to potential cumulative impacts to each of these environmental
components. As a result, the project’s contribution to cumulative impacts associated with
biological resources, cultural resources, vibration, and construction noise would be cumulatively
considerable.
Mitigation Measures
Implementation of Mitigation Measures BIO-1 through BIO-3, CR-1 through CR-3, and NOI-1
through NOI-5 is required.
Significance after Mitigation
With the implementation of the above mitigation measures, the project’s contribution to
cumulative impacts associated with biological resources, cultural resources, vibration, and
construction noise would be reduce to less than significant.
c) Have environmental effects that would cause substantial adverse effects on human
beings, either directly or indirectly?
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-76 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016
3. Environmental Checklist
Less than Significant with Mitigation Incorporated. The implementation of the proposed
project could result in temporary noise increases during construction as well as vibration impacts
during construction. These noise and vibration impacts could represent significant adverse effects
on human beings.
Mitigation Measures
Implementation of Mitigation Measures NOI-1 through NOI-5 is required.
Significance after Mitigation
The implementation of the above mitigation measures would reduce the potential vibration
impacts as well as the construction noise level on the adjacent residents. This reduction in impact
would result in a less than significant noise and vibration impact.
Big Canyon Habitat Restoration and Water Quality Improvement Project 3-77 ESA / Project No. 130934
Initial Study / Mitigated Negative Declaration February 2016