Loading...
HomeMy WebLinkAbout2024-06-25 - AGENDA REPORTS - REAL PROPTY ACQUISITION APN 2812 008 900 AND 901Agenda Item: 17 CITY OF SANTA CLARITA AGENDA REPORT CONSENT CALENDAR CITY MANAGER APPROVAL: Li DATE: June 25, 2024 SUBJECT: REAL PROPERTY ACQUISITION OF 9.93 +/- ACRES, LOCATED AT 28700 BOUQUET CANYON ROAD, AND IDENTIFIED AS PORTIONS OF ASSESSOR PARCEL NUMBERS 2812-008-900 AND 2812-008-901 DEPARTMENT: Recreation and Community Services PRESENTER: Janine Prado RECOMMENDED ACTION City Council: Approve the acquisition of 9.93+/- acres Los Angeles County Assessor's Parcel Numbers 2812-008-900 and 2812-008-901 at a total cost of $205,000, which includes the property purchase price of $180,000 and $25,000 for due diligence, escrow, appraisal and closing costs. 2. Increase Miscellaneous Revenue Account 431-462101 (Site Improvements Fee Fund) to record $205,000 from the Integral Communities developer as part of the Master Case 21-151, Bouquet Canyon conditions of approval and increase Land Expenditure Account 4319000- 520104 to acquire 9.93+/- acres Los Angeles County Assessor's Parcel Numbers 2812-008- 900 and 2812-008-901. 3. Authorize the City Manager, or designee, to execute all documents, subject to City Attorney approval, contingent upon the appropriation of funds by the City Council. BACKGROUND The County of Los Angeles (County) is the owner of a parcel of real property located at 28700 Bouquet Canyon Road. The subject property is comprised of approximately 9.93 acres identified as portions of Assessor's Parcel Numbers 2812-008-900 and 2812-008-901, located in the City of Santa Clarita (City). The County agrees to sell and convey this property to the City for the purchase price of $180,000 based on a completed appraisal report. Page 1 Packet Pg. 262 The property purchase price of $180,000 and the $25,000 for due diligence, escrow, appraisal, and closing costs will be covered by the developer, Integral Communities, for a total estimated cost of $205,000. The acquisition is pursuant to the conditions of approval for Master Case 21-151 (Bouquet Canyon Project Map Revision). The Bouquet Canyon Project was approved by the City Council on November 10, 2020. These conditions include various entitlements for the Map Revision in addition to those associated with the Bouquet Canyon Project under Master Case 18-089. The latter includes several parcels, as identified in the document. The acquisition is necessary for the proposed improvements shown on their property per Tentative Tract Map 82126. These improvements include the construction of a portion of the Bouquet Canyon Realignment including the bridge over Bouquet Creek and the T-intersection of the new Copper Hill Drive alignment, slope along Bouquet Canyon Realignment, secondary access to the site and associated improvements, a debris basin, an infiltration basin, a concrete channel, a low -flow channel including the 4 x 4 foot Reinforced Concrete Block and other miscellaneous improvements. The acquisition will also facilitate the relocation of the County's sewer main and other infrastructures. As part of the sewer realignment project, sewer services must be provided for the County -owned facility at Assessor's Parcel No. 2812-008-900. Additionally, an addendum was prepared at the County's request, determining that no further environmental review is required. The addendum is attached as a reading file. The acquisition is driven by the conditions of approval for the Bouquet Canyon Project to facilitate the realignment of Bouquet Canyon Road and associated infrastructure components. ALTERNATIVE ACTION Other action as determined by the City Council. FISCAL IMPACT Upon approval of the recommended action, the $205,000 from the developer will be deposited into Miscellaneous Revenue Account 431-462101 (Site Improvements Fee Fund) and the funds will be appropriated to Land Expenditure Account 4319000-520104 (Site Improvements Fee Fund) to acquire the 9.93+/- acres Los Angeles County Assessor's Parcel Numbers 2812-008- 900 and 2812-008-901 from Los Angeles County. ATTACHMENTS Location Map Bouquet Canyon EIR Addendum (available in the City Clerk's Reading File) Page 2 Packet Pg. 263 N city of SANTA CGLARITA A Property Acquisition for Portions of APN 2812-008-900 0 125 250 and 2812-008-901 ► 1 Street centeriines developed & maintained by City of Santa Clarita GIS • ! Limits Acquisition City Boundary The City of Santa Ciarita does not warrant 9.92 acres the accuracy of the data and assumes no Proposed Alignment Existfng Parcel ffabilfty for any errors or omissions. Boundary County Ownership Map prepared by: City of Santa darita GIS Division ¢,\PROJECTSjPR&C5\240617fljBouquet Acquisition h- 1. E 17.a I; Packet Pg. 264 Addendum No. 2 to the Bouquet Canyon Residential and Roadway Realignment Project Environmental Impact Report City of Santa Clarita LEAD AGENCY: City of Santa Clarita Community Development -Planning Division 23920 West Valencia Boulevard Santa Clarita, CA 91355 Contact: Hai Nguyen, Associate Planner (661) 255-4365 PREPARED BY: Michael Baker International 3760 Kilroy Airport Way, Suite 270 Long Beach, California 90806 Contact: Brent Schleck (562) 200-7181 June 2023 Page Intentionally Left Blank List Of Appendices Appendix A: Biological Resources A.1: Addendum to the Biological Technical Report (February 2022) A.2: Addendum to the Oak Tree Report (February 2022) Appendix B: Technical Memorandum Summarizing Revisions to the 2019 Biological and Cultural Resources Technical Reports (February 2022) Appendix C Geology and Soils C.1: Geotechnical Memorandum from LGC Geotechnical (October 2021) C.2: Geotechnical Memorandum from LGC Geotechnical (April 2022) Appendix D: Urban Stormwater Mitigation Plan (March 2022) 3 I. Introduction and Project Description A. Original Bouquet Canyon Project — City Approvals and California Environmental Quality Act (CEQA) Findings The Bouquet Canyon Residential and Roadway Realignment Project was approved by the City of Santa Clarita City Council on November 10, 2020. The approved project was a master plan for a residential community and realignment of a segment of Bouquet Canyon Road, which is a planned objective in the Santa Clarita General Plan Circulation Element. The approved project is sited on 74.66 acres of undeveloped land located in the Saugus area of the City of Santa Clarita. The Project Site location is illustrated in Figure 1. The approved project (see Figure 2) consists of up to 375 for -sale homes in five distinct neighborhoods, along with extensive site improvements, including internal streets and driveways, storm drainage, water, and sewer facilities, electrical and natural gas facilities, private recreation areas, public parkland and trails, and a reconfiguration of Bouquet Creek and its adjacent floodplain to provide flood control within the project and maintain regular stream flows already occurring. The approved project also includes construction of a new segment of Bouquet Canyon Road to follow the general alignment identified in the Santa Clarita General Plan Circulation Element. This is intended to facilitate local and regional travel through a more direct route between Plum Canyon Road and Vasquez Canyon Road. At the time of project approval, it was estimated that the project would be constructed over a five-year period, with all planning areas fully developed and occupied by 2024-2025. City Council approvals included: a. Tentative Tract Map No. 82126—to subdivide the subject property into 19 lots for residential land uses, streets, private drives, drainage infrastructure, slopes, and various open space lots. b. Conditional Use Permit 18-004—for private gating of multi -family units, any building heights greater than 35 feet, and cluster development. c. Architectural Design Review 18-010—for the proposed building design, styles, and forms. d. Development Review 18-009—for the proposed physical design and layout of the project. e. Hillside Development Review (Class 4) 18-001—to develop land with average cross slopes of 10 percent or more. f. Ridgeline Alteration Permit 18-001—for development on and near a designated significant ridgeline in the ridgeline preservation overlay zone. g. Oak Tree Permit (Class 4) 19-003—required for any encroachments or removals of protected oak trees. h. Landscape Plan Review 19-017—for the proposed landscape plan. i. Certification of Final Environmental Impact Report (EIR). 4 Findings of Final EIR Significant/Unavoidable Impacts • None were identified. Less Than Significant With Mitigation Measures Incorporated a. Air Quality The project could potentially conflict with or obstruct implementation of the applicable air quality plan due to the potential to exceed criteria pollutant emissions thresholds due to fossil fuel combustion emissions during site construction. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.2-1: All off -road diesel -powered construction equipment greater than 50 horsepower shall meet the EPA -certified Tier 4 emission standards. In addition, all construction equipment shall be outfitted with best available control technologies (BACT) devices certified by GARB. Any emissions control device used by the contractor shall achieve emissions reductions that are no less than what could be achieved by a Level 4 diesel emissions control strategy for a similarly sized engine as defined by CARB regulations. A copy of each unit's certified tier specification, BACT documentation, and CARB or SCAQMD operating permit shall be provided at the time of mobilization of each applicable unit of equipment. MM 3.2-2: The contractor shall utilize hauling trucks no larger than Medium Heavy Duty Trucks (MHDT) (i.e., gross vehicle weight rating [GVWR] 14,001 - 33,000 pounds) during the site preparation and grading phases of construction. The project could potentially result in a cumulatively considerable net increase of the criteria pollutant NOx due to fossil fuel combustion emissions during site construction. This impact would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.2-1: All off -road diesel -powered construction equipment greater than 50 horsepower shall meet the EPA -certified Tier 4 emission standards. In addition, all construction equipment shall be outfitted with best available control technologies (BACT) devices certified by GARB. Any emissions control device used by the contractor shall achieve emissions reductions that are no less than what could be achieved by a Level 4 diesel emissions control strategy for a similarly sized engine as defined by CARB regulations. 5 A copy of each unit's certified tier specification, BACT documentation, and CARB or SCAQMD operating permit shall be provided at the time of mobilization of each applicable unit of equipment. MM 3.2-2: The contractor shall utilize hauling trucks no larger than Medium Heavy Duty Trucks (MHDT) (i.e., gross vehicle weight rating [GVWR] 14,001 - 33,000 pounds) during the site preparation and grading phases of construction. 3. The project could potentially expose sensitive receptors to substantial concentrations of PMIo and PM2.5 during project construction. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.2-1: All off -road diesel -powered construction equipment greater than 50 horsepower shall meet the EPA -certified Tier 4 emission standards. In addition, all construction equipment shall be outfitted with best available control technologies (BACT) devices certified by GARB. Any emissions control device used by the contractor shall achieve emissions reductions that are no less than what could be achieved by a Level 4 diesel emissions control strategy for a similarly sized engine as defined by CARB regulations. A copy of each unit's certified tier specification, BACT documentation, and CARB or SCAQMD operating permit shall be provided at the time of mobilization of each applicable unit of equipment. MM 3.2-2: The contractor shall utilize hauling trucks no larger than Medium Heavy Duty Trucks (MHDT) (i.e., gross vehicle weight rating [GVWR] 14,001 - 33,000 pounds) during the site preparation and grading phases of construction. b. Biological Resources 1. The project could result in significant impacts to a rare plant species, i.e., the slender mariposa lily, and to a sensitive wildlife species, i.e., the burrowing owl. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.3-1: Preserve or Replace Slender Mariposa Lilies Mitigation for project impacts to the slender mariposa -lily (Calochortus clavatus var. gracilis) shall include one or more of the following, implemented in consultation with the City and CDFW prior to construction: • Prior to construction, a mitigation plan shall be developed that describes methods to mitigate for impacts to slender mariposa lily at a 1:1 ratio. The mitigation plan shall include a description of the 0 mitigation site, seed/bulb collection and planting methods, maintenance and monitoring requirements, and performance standards to measure the success of the mitigation. Slender mariposa lily bulbs shall be collected at the end of the growing season and prior to ground disturbance, or seeds shall be obtained from a native plant nursery if available. The seeds/bulbs shall be planted within an appropriate on -site or off -site mitigation area, which will be conserved as open space in perpetuity. • Payment into a mitigation bank that supports this rare plant species. • Preservation of land that contains the rare plant species. MM 3.3-2: Burrowing Owl Avoidance In compliance with the CDFW Staff Report on Burrowing Owl Mitigation (2012), a take avoidance survey shall be conducted on the study area within 14 days prior to ground disturbance to determine presence of burrowing owl. If the take avoidance survey is negative and burrowing owl is confirmed absent, then ground -disturbing activities shall be allowed to commence, and no further mitigation would be required. If burrowing owl is observed during the take avoidance survey, active burrows shall be avoided by the project in accordance with the CDFW's Staff Report. The CDFW shall be immediately informed of any burrowing owl observations. A Burrowing Owl Protection and Relocation Plan shall be prepared by a qualified biologist, which must be sent for approval by CDFW prior to initiating ground disturbance. The plan shall detail avoidance measures that shall be implemented during construction and passive or active relocation methodology. Relocation shall only occur September 1 through January 31, outside of the nesting season. 2. The project would impact a southern willow scrub/giant reed stand habitat, a sensitive natural community and other riparian habitat along Bouquet Creek. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.3-3: Secure CDFW Streambed Alteration Agreement Prior to the City's issuance of a grading permit, the applicant shall demonstrate that a Streambed Alteration Agreement has been issued by the CDFW. Temporary impact areas under CDFW jurisdiction shall be returned to pre -project topographic contours once the project has been completed. Permanent impacts to areas under CDFW jurisdiction for southern willow scrub/giant reed stand (0.70 acres) shall be mitigated through on -site or off -site enhancement, restoration, and/or creation of CDFW jurisdictional streambed at ratio of no less than 1:1. Given that the remaining portion of Bouquet Canyon Creek is dominated by invasive giant reed stands, which is of extremely low biological function and value 7 and contributes to downstream infestation of giant reed, the remaining permanent impacts to CDFW jurisdiction (8.63 acres) shall be mitigated through on -site or off -site enhancement, restoration, and/or creation of CDFW jurisdictional streambed at a ratio of no less than 0.5:1. Best management practices (BMPs) to minimize and avoid impacts to CDFW jurisdiction during and after construction will be addressed as part in the Streambed Alteration Agreement. Minimization and avoidance measures may include, but are not limited to, the following: • Construction -related equipment will be stored in developed areas, outside of drainages. No equipment maintenance will be done within or adjacent to the drainage. • Mud, silt, spoil sites, raw cement, asphalt, or other pollutants from construction activities will not be placed within or adjacent to the drainage. • Open trenches or other excavated areas will be properly secured at the end of the day to avoid entrapment of animals, or an escape ramp will be provided. • To avoid attracting predators during construction, the project shall be kept clean of debris to the extent possible. All food -related trash items shall be enclosed in sealed containers and regularly removed from site. • Construction personnel shall strictly limit their activities, vehicles, equipment and construction material to the proposed project footprint, staging areas, and designated routes of travel. • Exclusion fencing shall be installed to demarcate the limits of disturbance and shall be maintained until the completion of construction activities. • To the extent feasible, construction will be conducted outside of the bird nesting season (see mitigation measure 3.3-5, later herein). 3. The project would have temporary and permanent impacts to non -wetland waters of the United States (WUS). Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.3-4: Provide Evidence of Section 404 and 401 Permits Prior to the City's issuance of a grading permit, the applicant shall demonstrate that the appropriate regulatory permits have been issued by the USACE and RWQCB. Temporarily impacted WUS shall be returned to pre -project topographic contours once the project has been completed. Compensatory mitigation for permanent impacts to WUS shall be s required as part of subsequent permitting requirements. Permanent impacts to WUS shall be mitigated through on -site or off -site enhancement, restoration, and/or creation of jurisdictional streambed at a ratio of no less than 1:1. BMPs to minimize and avoid impacts to WUS during and after construction will be addressed as part of the USACE and RWQCB permitting process. Minimization and avoidance measures may include, but are not limited to, the following: • Construction -related equipment will be stored in developed areas, outside of the drainage. No equipment maintenance will be done within or adjacent to the drainage. • Source control and treatment control BMPs will be implemented to minimize the potential contaminants that are generated during and after construction. Water quality BMPs will be implemented throughout the project to capture and treat potential contaminants. • Substances harmful to aquatic life will not be discharged into the drainage. All hazardous substances will be properly handled and stored. • A Storm Water Pollution Prevention Plan will be prepared to prevent sediment from entering the drainage during construction. • To avoid attracting predators during construction, the project will be kept clean of debris to the extent possible. All food -related trash items will be enclosed in sealed containers and regularly removed from site. • Construction personnel will strictly limit their activities, vehicles, equipment and construction material to the proposed project footprint, staging areas, and designated routes of travel. • Exclusion fencing will be installed to demarcate the limits of disturbance. The exclusion fencing should be maintained until the completion of construction activities. 4. The project could potentially impact migratory birds in violation of the Migratory Bird Treaty Act. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.3-5: Avoid Disruption of Active Bird Nests during Construction Schedule construction activities (i.e., earthwork, clearing, and grubbing) outside of the general bird nesting season for migratory birds, if feasible. This season is February 15 through August 31 for songbirds and January 15 through August 31 for raptors. If construction activities (i.e., earthwork, clearing, and grubbing) must occur during the general bird nesting season for migratory birds and raptors, a qualified biologist shall perform a preconstruction survey of E potential nesting habitat to confirm the absence of active nests belonging to migratory birds and raptors afforded protection under the Migratory Bird Treaty Act and California Fish and Game Code. The preconstruction survey shall be performed no more than seven days prior to the commencement of construction activities. The results of the preconstruction survey shall be documented by the qualified biologist. If construction is inactive for more than seven days, an additional survey shall be conducted. If the qualified biologist determines that no active migratory bird or raptor nests occur, the activities shall be allowed to proceed without any further requirements. If the qualified biologist determines that an active migratory bird or raptor nest is present, no construction within 300 feet (500 feet for raptors) of the active nest shall occur until the young have fledged the nest and the nest is confirmed to no longer be active, or as determined by the qualified biologist. The biological monitor may modify the buffer or propose other recommendations in order to minimize disturbance to nesting birds. c. Cultural Resources 1. The project could potentially impact archaeological resources due to the potential presence of Native American cultural resources and human burial sites. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.4-1: Archaeological and Native American Monitoring Program The applicant shall retain a Secretary of the Interior Professional Qualified archaeologist and/or Registered Professional Archaeologist to develop a monitoring program for the project site in areas of young alluvium and colluvium (see Appendix D: Figure 10, Areas of Young Alluvium or Colluvium Deposits). This program shall also address potential discovery of the Ruiz cemetery on the main ridgeline. The monitoring program shall include the archaeological context, rationale for monitoring, Native American participation, monitoring procedures, and what to do with resource/remains discoveries. The monitoring program shall require an archaeologist and Native American monitor from the Fernandeno Tataviam Band of Mission Indians to hold a preconstruction meeting with the grading contractor and both are to be present during initial ground -disturbing activities within the areas of young alluvium and colluvium. Both archaeological and Native American monitors shall have the authority to temporarily halt or redirect grading and other ground -disturbing activities in the event cultural resources are encountered. If potentially significant cultural material is encountered, the monitors shall make recommendations regarding the treatment of the discovery. Impacts to significant archaeological deposits should be 10 avoided if feasible, but if such impacts cannot be avoided, the deposits should be evaluated for eligibility to the California Register of Historical Resources (CRHR). If the deposit is not CRHR-eligible, no further protection of the find is necessary. If the deposits are CRHR-eligible, impacts shall be avoided or mitigated. Acceptable mitigation may consist of but is not necessarily limited to systematic recovery and analysis of archaeological deposits, recording the resource, preparation of a report of findings, and accessioning recovered archaeological materials at an appropriate curation facility. MM 3.4-2: Chari/Suraco Cemetery Identification and Avoidance Prior to the issuance of a grading permit associated with Planning Area 1, the project developer shall provide the City with evidence of the exact location of the early twentieth century -period Chari/Suraco cemetery, using noninvasive techniques, and shall delineate those areas in the field to provide visual markers to ensure that grading crews avoid that burial site. The Chari/Suraco cemetery shall be included in the permanent open space area to be preserved in the land immediately east of Planning Area 1. 2. The project could potentially disturb human remains. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.4-1: Archaeological and Native American Monitoring Program The applicant shall retain a Secretary of the Interior Professional Qualified archaeologist and/or Registered Professional Archaeologist to develop a monitoring program for the project site in areas of young alluvium and colluvium (see Appendix D: Figure 10, Areas of Young Alluvium or Colluvium Deposits). This program shall also address potential discovery of the Ruiz cemetery on the main ridgeline. The monitoring program shall include the archaeological context, rationale for monitoring, Native American participation, monitoring procedures, and what to do with resource/remains discoveries. The monitoring program shall require an archaeologist and Native American monitor from the Fernandeno Tataviam Band of Mission Indians to hold a preconstruction meeting with the grading contractor and both are to be present during initial ground -disturbing activities within the areas of young alluvium and colluvium. Both archaeological and Native American monitors shall have the authority to temporarily halt or redirect grading and other ground -disturbing activities in the event cultural resources are encountered. If potentially significant cultural material is encountered, the monitors shall make recommendations regarding the treatment of the discovery. Impacts to significant archaeological deposits should be avoided if feasible, but if such impacts cannot be avoided, the deposits should be evaluated for eligibility to the California Register of Historical 11 Resources (CRHR). If the deposit is not CRHR-eligible, no further protection of the find is necessary. If the deposits are CRHR-eligible, impacts shall be avoided or mitigated. Acceptable mitigation may consist of but is not necessarily limited to systematic recovery and analysis of archaeological deposits, recording the resource, preparation of a report of findings, and accessioning recovered archaeological materials at an appropriate curation facility. MM 3.4-2: Chari/Suraco Cemetery Identification and Avoidance Prior to the issuance of a grading permit associated with Planning Area 1, the project developer shall provide the City with evidence of the exact location of the early twentieth century -period Chari/Suraco cemetery, using noninvasive techniques, and shall delineate those areas in the field to provide visual markers to ensure that grading crews avoid that burial site. The Chari/Suraco cemetery shall be included in the permanent open space area to be preserved in the land immediately east of Planning Area 1. d. Geology and Soils 1. The project could potentially impact a unique paleontological resource where excavation work is conducted within the sedimentary layers of the Castaic and Saugus Formations. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.6-1: The developer shall retain a qualified paleontologist meeting the Society of Vertebrate Paleontology Standards to develop a monitoring program for the project site in areas where Castaic and Saugus Formation sedimentary layers are exposed or are likely to be exposed during project construction. The qualified paleontologist shall provide technical and compliance oversight of all work as it relates to paleontological resources and shall be authorized to stop work where potential paleontological resources are discovered to provide an opportunity to examine, recover, and characterize such materials. Additionally, the qualified paleontologist shall conduct construction worker paleontological resources sensitivity training at the project kickoff meeting, prior to ground -disturbing activities. Any significant paleontological resources collected during project -related excavations shall be curated into an accredited repository. The qualified paleontologist shall prepare a final monitoring and mitigation report for submittal to the City that documents the results of the monitoring effort and any discoveries. e. Hazards and Hazardous Materials 1. The project would potentially have an impact due to the presence of an abandoned oil/gas well located in the central portion of the project site between a planning area 12 and the new segment of Bouquet Canyon Road. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.8-1: Prior to the issuance of a grading permit, the project applicant shall test the oil/gas well located on APN 2812-008-022 for leakage. The soils around the oil/gas well shall also be tested for significant amounts of hydrocarbons. The results of the soils testing shall be submitted to the City of Santa Clarita Planning Division for review. Any soils containing significant amounts of hydrocarbons shall be disposed of in accordance with local, state, and federal laws. 2. The project could potentially result in a significant impact due to the exposure of people or structures to a significant risk of loss, injury, or death involving wildland fires. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.15-1: Construction Fire Prevention Plan: The Project Applicant shall develop a Construction Fire Prevention Plan that addresses training of construction personnel and provides details of fire -suppression procedures and equipment to be used during construction. Information contained in the plan shall be included as part of project -related environmental awareness training. At minimum, the plan shall include the following: • Procedures for minimizing potential ignition, including, but not limited to, vegetation clearing, parking requirements/restrictions, idling restrictions, smoking restrictions, proper use of gas -powered equipment, use of spark arrestors, and hot work restrictions; • Work restrictions during periods of high winds, Red Flag Warnings and High to Extreme Fire Danger days; • Fire coordinator role and responsibility; • Worker training for fire prevention, initial attack firefighting, and fire reporting; • Emergency communication, response, and reporting procedures; • Coordination with local fire agencies to facilitate agency access through the project site; • Emergency contact information MM 3.15-2: Fuel Modifications, Landscaping, and Irrigation The Construction Contractor shall ensure the implementation of all construction -phase flammable vegetation removal, fuel modification landscape materials, and irrigation systems required by the Los Angeles 13 County Fire Department, prior to combustible building materials being delivered to the site. MM 3.15-3: Emergency Vehicle Access Plan During Construction To avoid impeding emergency vehicle and evacuation traffic around construction vehicles and equipment, the Project Applicant, in consultation with the City, shall develop an Emergency Vehicle Access Plan that includes the following: • Evidence of advanced coordination with emergency service providers, including but not necessarily limited to police departments, fire departments, ambulance services, and paramedic services; • Emergency service providers will be notified of the proposed project locations, nature, timing, and duration of any construction activities, and will be asked for advice about any road access restrictions that could impact their response effectiveness; and • Project construction schedules and routes designed to avoid restricting movement of emergency vehicles to the best extent possible. Provisions to be ready at all times to accommodate emergency vehicles. Provisions could include the use of platings over excavations, short detours, and/or alternate routes. f. Noise 1. The project would generate temporary construction noise levels that could result in adverse impacts to the nearest existing homes. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.10-1: To reduce noise impacts due to construction, the project applicant shall demonstrate, to the satisfaction of the City of Santa Clarita Community Development Director, that the project complies with the following: Prior to approval of grading plans and/or issuance of building permits, plans shall include a note indicating that noise -generating project construction activities, including haul truck deliveries, shall only occur between the hours of 7:00 a.m. to 7:00 p.m. Monday through Friday, 8:00 a.m. to 6:00 p.m. on Saturdays, and with no activity allowed on Sundays or federal holidays. The project construction supervisor shall ensure compliance with the note and the City of Santa Clarita shall conduct periodic inspections at its discretion. • During all project construction, the construction contractors shall equip all construction equipment, fixed or mobile, with properly operating and maintained mufflers, consistent with manufacturers' 14 standards. The construction contractor shall place all stationary construction equipment so that emitted noise is directed away from the nearest noise -sensitive receptors. • The construction contractor shall locate equipment staging in areas that would create the greatest distance between construction -related noise sources and noise -sensitive receivers nearest the site during all project construction. g. Transportation/Traffic 1. The project could potentially conflict with the City of Santa Clarita's traffic analysis guidelines due to potential impacts on the level of service (LOS) at multiple intersections in the project vicinity. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.12-1: David Way and Old Bouquet Canyon East: Remove existing traffic signal. Close David Way between Old Bouquet Canyon Road and Copper Hill Drive (eliminates south leg of the David Way and Copper Hill Drive intersection). Construct new east leg of David Way at Copper Hill Drive intersection and connect to Old Bouquet Canyon Road. At the David Way and Copper Hill Drive intersection, construct median island to restrict left -turn movement (southbound left) from David Way to Copper Hill Drive and install stop sign at David Way. MM 3.12-2: Benz Road and Copper Hill Drive: Construct median island to restrict left -turn movement (northbound left) from Benz Road to Copper Hill Drive. MM 3.12-3: New Bouauet Canvon Road and Old Bouauet Canvon East: Installation of a traffic signal. MM 3.12-4: The project proponent shall pay the project's fair share contribution to a collective set of improvements around the Project site would alter and improve traffic flow on Benz Road, Copper Hill Drive, Kathleen Avenue, David Way, and Bouquet Canyon Road. MM 3.12-5: Bouquet Canyon Road and Vasquez Canyon Road: The project proponent shall pay the project's fair share (2%) of the cost of these improvements: Add a northbound right -turn de -facto lane and add a dedicated westbound left -turn lane. Installation of traffic signal with northbound and southbound split -phasing. MM 3.12-6: New Bouauet Canvon Road and Old Bouauet Canvon Road West: The project proponent shall pay the project's fair share (25%) of the cost of these improvements: Construct median island to restrict left -turn movement (southbound left) from Old Bouquet Canyon Road to eastbound New Bouquet Canyon Road. 15 MM 3.12-7: Kathleen Avenue and Copper Hill Drive: The project proponent shall pay the project's fair share (2%) of the cost of these improvements: installation of a traffic signal and widen Copper Hill Drive from 2 lanes to 4 lanes from Benz to Kathleen. MM 3.12-8: Golden Valley Road and Plum Canyon Road: The project proponent shall pay the project's fair share (8%) of the cost of these improvements: Update corridor signal timing coordination, as needed, due to future cumulative traffic volumes. MM 3.12-9: Seco Canyon Road and Bouquet Canyon Road: The project proponent shall pay the project's fair share (42%) of the cost of these improvements: Add second southbound left -turn lane, add one eastbound right -turn lane, and add third northbound through lane. MM 3.12-10: Bouquet Canyon Road and Newhall Ranch Road: The project proponent shall pay the project's fair share (8%) of the cost of these improvements: Add third westbound left -turn lane. MM 3.12-11: Golden Valley Road and Newhall Ranch Road: The project proponent shall pay the project's fair share (0.5%) of the cost of these improvements: Extend median pocket from 300 to 500 feet plus taper. Update corridor signal timing coordination, as needed, due to future cumulative traffic volumes. MM 3.12-12: New Bouquet Canyon Road and Old Bouquet Canyon Road East (Copper Hill): The project proponent shall pay the project's fair share (5%) of the cost of these improvements: Add second northbound through lane, add second southbound through lane. 2. The project would potentially result in inadequate emergency access to Planning Areas 1, 2, and 3. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.12-13: A secondary access to the proposed segment of Bouquet Canyon Road shall be provided for the homes in Planning Areas 1, 2 and 3 that are accessible only to that new roadway segment. This secondary access shall be identified on the project plans and approved by the County Fire Department and City of Santa Clarita, prior to approval of a Final Tract Map. h. Tribal Cultural Resources 1. The project could potentially impact tribal cultural resources of the Fernandeno Tataviam Band of Mission Indians. Impacts would be reduced to a less than significant level with implementation of the following mitigation measure: MM 3.13-1: The applicant shall retain a professional Native American monitor procured by the Fernandeno Tataviam Band of Mission Indians to 16 observe all clearing, grubbing, and grading operations within areas designated sensitive for tribal cultural resources, including areas with young alluvium and colluvium soil conditions. Monitoring activities. If cultural resources are encountered, the Native American monitor will have the authority to request that ground -disturbing activities cease within 60 feet of discovery to assess and document potential finds in real time. One monitor will be required on -site for all ground -disturbing activities in areas designated through additional consultation. However, if ground -disturbing activities occur in more than one of the designated monitoring areas at the same time, then the parties can mutually agree to an additional monitor, to ensure that simultaneously occurring ground - disturbing activities receive thorough levels of monitoring coverage. If human remains or funerary objects are encountered during any activities associated with the project, work in the immediate vicinity (within a 100-foot buffer of the find) shall cease and the County coroner shall be contacted pursuant to California Health and Safety Code Section 7050.5 and that code shall be enforced for the duration of the project. Inadvertent discoveries of human remains and/or funerary objects and the subsequent disposition of those discoveries shall be decided by the most likely descendant as determined by the Native American Heritage Commission, should those findings be determined as Native American in origin. i. Wildfire 1. The project could potentially exacerbate fire risk during construction. Impacts would be reduced to a less than significant level with implementation of the following mitigation measures: MM 3.15-1: Construction Fire Prevention Plan: The Project Applicant shall develop a Construction Fire Prevention Plan that addresses training of construction personnel and provides details of fire -suppression procedures and equipment to be used during construction. Information contained in the plan shall be included as part of project -related environmental awareness training. At minimum, the plan shall include the following: • Procedures for minimizing potential ignition, including, but not limited to, vegetation clearing, parking requirements/restrictions, idling restrictions, smoking restrictions, proper use of gas -powered equipment, use of spark arrestors, and hot work restrictions; • Work restrictions during periods of high winds, Red Flag Warnings and High to Extreme Fire Danger days; • Fire coordinator role and responsibility; 17 • Worker training for fire prevention, initial attack firefighting, and fire reporting; • Emergency communication, response, and reporting procedures; • Coordination with local fire agencies to facilitate agency access through the project site; • Emergency contact information MM 3.15-2: Fuel Modifications, Landscaping, and Irrigation The Construction Contractor shall ensure the implementation of all construction -phase flammable vegetation removal, fuel modification landscape materials, and irrigation systems required by the Los Angeles County Fire Department, prior to combustible building materials being delivered to the site. MM 3.15-3: Emergency Vehicle Access Plan During Construction To avoid impeding emergency vehicle and evacuation traffic around construction vehicles and equipment, the Project Applicant, in consultation with the City, shall develop an Emergency Vehicle Access Plan that includes the following: • Evidence of advanced coordination with emergency service providers, including but not necessarily limited to police departments, fire departments, ambulance services, and paramedic services; • Emergency service providers will be notified of the proposed project locations, nature, timing, and duration of any construction activities, and will be asked for advice about any road access restrictions that could impact their response effectiveness; and • Project construction schedules and routes designed to avoid restricting movement of emergency vehicles to the best extent possible. Provisions to be ready at all times to accommodate emergency vehicles. Provisions could include the use of platings over excavations, short detours, and/or alternate routes. 18 Less Than Significant or No Impact • Aesthetics • Agriculture and Forestry Resources • Air Quality - impacts due to other emissions, such as odors adversely affecting a substantial number of people • Biological Resources o Impacts due to conflict with local policies or ordinances protecting biological resources o Impacts due to conflict with provisions of an adopted habitat conservation plan, natural community conservation plan, or other approved habitat conservation plan o Impacts due to the project affecting a Significant Ecological Area o Cumulative impacts • Cultural Resources o Impacts due to a substantial adverse change in the significance of a historical resource o Cumulative impacts • Energy • Geology and Soils o Impacts due to rupture of a known earthquake fault o Impacts due to strong seismic ground shaking o Impacts due to seismic -related ground failure o Impacts due to landslides o Impacts due to soil erosion or lose of topsoil o Impacts due to location on an unstable geologic unit or soil or on a geologic unit or soil that would become unstable o Impacts due to expansive soil o Impacts due to soils incapable of supporting septic tanks or other disposal systems o Impacts due to destruction, covering, or modification of a unique geologic or physical feature o Cumulative impacts • Greenhouse Gas Emissions • Hazards and Hazardous Materials o Impacts due to hazardous emissions, materials, substances, or waste within one - quarter mile of an existing or proposed school o Impacts due to the project being located on a site included on a list of hazardous materials sites o Impacts due to the project being located within an airport land use plan area o Impacts due to the project being within the vicinity of a private airstrip o Impacts during operation due to the project impairing implementation of an emergency response plan or emergency evacuation plan o Cumulative impacts • Hydrology and Water Quality • Land Use • Mineral Resources 19 • Noise o Impacts due to the generation of excessive groundborne vibration levels o Impacts due to the project being located within an airport land use plan area o Impacts due to the project being within the vicinity of a private airstrip o Cumulative impacts • Population and Housing • Public Services • Recreation • Transportation o Impacts due to conflict with CEQA Guidelines Section 15064.3(b) o Impacts due to a geometric design feature or incompatible uses o Impacts due to a change in air traffic patterns • Utilities and Service Systems • Wildfire o Impacts due to impairment of an adopted emergency response plan or emergency evacuation plan o Impacts due to the project exacerbating wildfire risks and thereby exposing project occupants to pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire o Impacts due to exposing people or structures to significant risks as a result of runoff, post -fire slope instability, or drainage changes o Cumulative impacts B. Bouquet Canyon Residential Development and Roadway Realignment 2022 EIR Addendum No. 1 The Original Project, described above, was revised in 2022. The revised project site plan is available as Figure 2. The 2022 revisions, and the associated City approvals, are provided in the list below. 1. Amended Tentative Tract Map • Adjustment to the Tentative Map to include additional acquired parcels: o Addition of APN 2812-038-002 (formerly Toll Bros property) to accommodate the relocation of the recreation center and the construction of New Bouquet Canyon Road. o Addition of APN 2812-008-002 (aka the "Donut Hole" property) to accommodate reconfiguration of residential units located within planning area (PA)-1. o Addition of APN 2812-008-008 (formerly Davenport property) to accommodate proposed off -site trailhead improvements. • Relocation of a residential recreation facility (recreation center) from PA-1 to an adjacent parcel in the Open Space zone (APN 2812-038-002). 20 • Modifications to the single-family lots in PA-1 and PA-3 due to the relocation of the recreation center and to avoid the potential cemetery location. • Elimination of PA -IA per City Council conditions of approval. • Updated channel design to reflect most recent County plan check corrections. • Adjustment to the location of the required pedestrian bridge crossing due to revised channel design. • Slope grading for Copper Hill Drive retaining wall in APN 2812-008-008. • Construction of a trailhead parking area accessing the Haskell Canyon Open Space Area along Copper Hill Drive to accommodate equestrian parking and a new sidewalk. • Construction of a trailhead on the Davenport property (APN 2812-008-008) located across the proposed extension of Copper Hill Drive, northeast of the project site. 2. Conditional Use Permit • To locate a recreation center within the Open Space zone. • To construct a trailhead/park within the Urban Residential (UR5) zone 3. Development Review • Development review of the relocated recreation center. 4. Architectural Design Review • Architectural review of the recreation center building. The 2022 project revisions resulted in an increase in the total grading quantities as compared to what was evaluated in the Bouquet Canyon EIR from 2,070,000 cubic yards of earthwork to 2,800,000 cubic yards of earthwork. The revised 2022 project proposed four, rather than five, residential planning areas, and a net reduction of four homes from the originally approved plan. Table 1, below, summarizes the key features of the 2022 project plan. 21 Table 1: Summary of Updated Development Plan Revised Project Development Plan U date Planning Areas/Infrastructure Type of Homes/Land Use # Residential Units Acreage PA-1 Single Family Detached 60 8.0 PA-2 Single Family Detached/Recreation Area 136 11.0 PA-3 Townhomes/Recreation Area 90 6.1 PA-4 Townhomes/Park 85 5.1 Drainage Channel 5.8 Low Flow Drainage Corridor 3.3 Debris Basins 1.9 Infiltration Basins 1.9 Open Space 30.0 Street 6.6 Total 371 79.7 The revisions also included a proposed Haskell Canyon Open Space area trailhead, to be located on the north side of Copper Hill Drive near the intersection of Copper Hill Drive and Benz Road, as well as a proposed trailhead at the Davenport Property. Other improvements included installation of a sidewalk on the north side of Copper Hill Drive. These revisions were evaluated in a 2022 Addendum to the Final EIR (i.e., Addendum No. 1) that was certified (hereafter, Certified EIR) in conjunction with approval of the original Bouquet Canyon Project, as noted above. The 2022 EIR Addendum was approved by the City's Planning Commission on June 7, 2022. Specifically, the Planning Commission adopted Resolution No. P22-05 approving Master Case 21-151, including Architectural Design Review 21-023, Conditional Use Permit 21-011, Development Review 21-016, and Tentative Tract Map 82126 Revision, to allow for revisions to the Tentative Tract Map, the relocation of the residential recreation facility in the Open Space zone, and construction of a park/trailhead for the previously -approved Bouquet Canyon Project. C. Proposed Project Revisions As conditioned in the original Bouquet Canyon Project, the applicant shall cooperate with the City to enter into an agreement with the County of Los Angeles to acquire the necessary off -site property in fee from the County of Los Angeles (APN: 2812-008-900) for the proposed improvements. Within this portion of the project, additional revisions to address off -site improvements were requested by the County of Los Angeles along the Project Site's eastern boundary with Los Angeles County's Camp Joseph Scott Juvenile Detention Center (Detention Center). The proposed revisions include installation of fencing and lighting along portion of the eastern Project Site boundary, as well as relocating sewer line connections at the northeast corner of the Project Site. The proposed revisions include installation of new fencing, lighting, and gates along the Project Site's eastern boundary with Detention Center. The Project Site's boundary with the turf field located on the western edge of the Detention Center property is currently defined by an existing chainlink fence and pole -mounted light fixtures. The proposed revision to the 2022 revised project would involve construction of a new fence to the west and north of this existing fence line, as well as installation of new pole -mounted light fixtures. The proposed fencing and lighting improvements are displayed in Figure 3. The proposed fence would be constructed of non -climb chainlink material and would be 14-feet-tall. The top 6 feet of the fence would be constructed of galvanized metal panels. The Project proposes to construct 921 linear feet of this fencing along the Project Site's eastern boundary. As shown in Figure 3, the construction of this fence west and north of the existing fence creates a space in between the two fences that is approximately 15-feet wide; however, this distance varies in some locations to approximately 35-feet-wide. This space between the fences would be graded to ensure a flat surface and would be covered with decomposed granite. Two gates would be installed to control access to the space created by the existing and proposed fences. The gates, approximately 15-feet wide, would be located at the northeast end of the proposed fence, as well as the southwest end of the proposed fence, as shown in Figure 3. The proposed revisions would also include installation of 11 new lights along this fence line. The lights would be mounted atop metal poles approximately 25-feet-high. As shown in Figure 3, the placement of the proposed lights would be staggered with the existing perimeter fence lighting. Additionally, proposed revisions to the 2022 revised project include relocation of a County of Los Angeles -owned 18-inch-diameter sewer main. As shown in Figure 4, the sewer main currently runs under the turf field on the western edge of the Detention Center, into the Project Site before turning north and connecting to sewer infrastructure within Bouquet Canyon Road. The proposed revision would abandon portion of this sewer main, beginning at the northeastern edge of the turf field within the Detention Center and would relocate the sewer main to the north. The abandoned sewer main would be slurry filled and left in -place. The proposed sewer main connection would run north under Bouquet Canyon Creek and would connect to existing sewer infrastructure within Bouquet Canyon Road. The proposed sewer line would consist of 333 feet of 18-inch-diameter vitrified clay pipe (VCP). Installation of this proposed sewer connection would involve jacking underneath Bouquet Canyon Creek, rather than trenching through the Creek. This would involve excavation of a bore pit and a receiving pit on either side of Bouquet Canyon Creek, with each pit approximately 10 feet wide, 30 feet long, and 10 feet deep. D. Purpose of EIR Addendum This document is the second Addendum (hereafter, Addendum No. 2) to the Certified EIR prepared in conjunction with approval of the original Bouquet Canyon Project, as noted above. It is intended to provide CEQA compliance for the proposed revisions to the previously approved project, described above, specifically with respect to the approvals necessary to permit the proposed revisions. 23 Preparation of an Addendum to a previously certified EIR is authorized by Section 15164 of the CEQA Guidelines, when the proposal consists of minor modifications to the originally approved project, and none of the following circumstances occur that would trigger preparation of a subsequent or supplemental EIR: 1. Substantial changes are proposed in the project which will require major revisions of the previous EIR due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects; 2. Substantial changes occur with respect to the circumstances under which the project is undertaken which will require major revisions of the previous EIR due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects; or 3. New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time the previous EIR was certified as complete, shows any of the following: a) The project will have one or more significant effects not discussed in the previous EIR; b) Significant effects previously examined will be substantially more severe than shown in the previous EIR; c) Mitigation measures or alternatives previously found not to be feasible would in fact be feasible, and would substantially reduce one or more significant effects of the project, but the project proponents decline to adopt the mitigation measure or alternative; or d) Mitigation measures or alternatives which are considerably different from those analyzed in the previous EIR would substantially reduce one or more significant effects on the environment, but the project proponents decline to adopt the mitigation measure or alternative. 24 pp,. $ cTs i -W 6 - SO o UN, A. Z-N A), - , !-Ok 1�' A4 114V q, Michael Baker — — Fk�snNc eauauEr caNraN Roan ROPOSED COPPERRILL DRVE CONNECTION NK 7-1 if -0 i' ,711 i zz i rrmi.mmrs, Q Approved Development Plan I N T E R N A T 1 0 N A L € Source: Lermar Homes of Califomia (02/2022) Figure 2 Proposed Lights 4 LO 1 / I i>t4` kCifSs ROA ' 07$.G L , / r• -. � GA TE P � — I LOT f e ■ _� pT 22 Existing Lights f L opos eri e, • f� p `t `'•. PR.OA`Cie CAUP VACN WAL %Ve A._rN%Y: z Existing Fence LOT 14 � _ ec ks�ss Ran r s ins' mrr�1 V 1.0 a.c. � I LOT 10 J. • ':� j.,; Proposed Gates zlk - SIKAND �- - Pq€PPRED BY A� , 0 Proposed Fences and Gates I N T E R N A T I O N A L € Source: Sikand 2023 Figure 3 56 Proposed Relocated.�� 'Sewer main k `- r \ LC}T 6 - �rRaarr+u�€r�rr� NEW V Existing Sewer Main, v JlA `s ..- i WAdFR 8A FIOW y-. r � nor to be Abandoned LOTXAo, / e _ , - - --- - pry �-,. � f i r - 7— a� L©T 22; q 1 /- - h 0.2 a.0 � `� �•Y;> Ix CCO435 ?D 8f ARAA"OMD { '1a f N � a / .c . 1.57 A:. D•� 4 �� I �R �Ar,L cnu� s RED lAIERA RrPeA r FVTZ ci r.6Wai 7 fDFRr VPFR SEPARAT PERYlT. a. 1 ` ©t liar - ° LOT 14 ° I oc �cr�ss xaAn �I Y aw�/�s' TlFyCAl� \ \ v 1.0 a.c. - ,p f 1 aoP. rver s� ° LP — l 3 sr Rt uax tiro R• Asrp' LOT 10 4 1.2 a.c. ■ jje I. s� , 0 Existing and Proposed Sewer Main I N T E R N A T I O N A L € Source: Sikand 2023 Figure 4 II. Comparative Impact Analysis Aesthetics The Certified EIR for the approved project addressed aesthetic impacts in Section 3.1 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to aesthetics, and no mitigation would be required. Further, the revised 2022 project EIR Addendum determined that the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. In short, the EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not have a substantial adverse effect on a scenic vista. There are no public scenic overlooks on or adjacent to the project site. Although the terrain on the project site could make it part of a scenic vista when viewed from a distant location, especially the ridgeline on the west side of the project site, which is identified in Exhibit CO-1 of the General Plan Conservation and Open Space Element, there are other General Plan -designated significant ridgelines in the immediate vicinity of the project site, all of which are taller than the ridgeline on the project site. Additionally, while a portion of this ridgeline would be graded in order to construct a General Plan - identified alignment for Bouquet Canyon Road, the project would still be consistent with Conservation and Open Space Element policies because the project would only alter a portion of the ridgeline and because the ridgeline is not the most substantial ridgeline in the community. b. The approved project would not substantially damage scenic resources within a state scenic highway as the nearest officially designated state scenic highway is located approximately 30 miles from the project site. c. The approved project would not substantially degrade the existing visual character or quality of public views of the site and its surroundings. While the project would result in alterations to the existing natural landscape and open character of the project site, the proposed structures would utilize materials and design elements consistent with the Community Character and Design Guidelines for the Saugus community. Further, the project provides visual buffers to soften the extent of building massing. d. The approved project would not adversely affect day or nighttime views in the area by creating a new source of substantial light or glare. The project would have lighting fixtures similar to those found in surrounding residential neighborhoods and would comply with the City's outdoor lighting standards (Santa Clarita Municipal Code Section 17.51.050, Outdoor Lighting Standards), which requires all lights to be directed downward and to be shielded so as to avoid upward lighting of the night sky and off -site glare. Further, homes would not be constructed of glare -producing materials. Comparative Analysis for Proposed Project Revisions a. The proposed grading of the significant ridgeline on -site would not be modified by the revised project. While a portion of the ridgeline would be graded as part of the approved project, as well as the 2022 revised project in order to construct a General Plan -identified alignment for Bouquet Canyon Road, the proposed project revisions would not result in any additional alteration of the ridgeline located on the project site. Specifically, project - related grading would be limited to minor grading to prepare the ground surface for installation of a proposed fence with light poles, grading an access path between the existing and proposed fence line, and digging two pits for installation of the sewer line underneath Bouquet Creek (approximately 10 feet wide by 30 feet long by 10 feet deep). These pits would be backfilled after the sewer line has been realigned. As stated in the Project Description, the proposed fence would be constructed of non -climb chainlink material and would be 14-feet-tall. The top 6 feet of the fence would be constructed of galvanized metal panels. The proposed light poles would be 25 feet tall. This is similar in height and material to the existing fencing and lighting that currently surrounds the fields and buildings at the Detention Center to the east. Therefore, the project would not result in a structure that would be out of character for the area. Given the relatively small amount of grading associated with the project, the limited amount of above- ground construction, and the existing perimeter fencing and lighting located along the project site's boundary with the Detention Center, the revised project would not result in a substantial adverse effect on a scenic vista. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, the revised project would not be visible from any officially designated state scenic highway, the nearest of which is located approximately 30 miles from the project site. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c. Under the revised project, a fence with light poles would be installed on the eastern boundary of the project site and a sewer line would be realigned, connecting to the existing sewer infrastructure within Bouquet Canyon Road. Portion of the sewer main would be abandoned in place, and a new alignment would connect the existing sewer main serving the Detention Center to existing sewer infrastructure within Bouquet Canyon Road. The proposed fence would be similar in height and scale to the existing chainlink fence that surrounds the Detention Center to the east. Also, there are a mixture of lighting types located at the Detention Center, including overhead, single -light poles similar to what is proposed (approximately 25-feet in height), as well as overhead, four - light poles illuminating the fields to the east of the project site that are approximately 35 to 40 feet tall (identified as "probation lights" in Figure 3). These existing fencing and lighting improvements on the Detention Center property are visible by motorists traversing Bouquet Canyon Road to the north; however, these views are obstructed by mature trees and vegetation along the road side and in the Bouquet Creek area. Upon 30 installation, the sewer improvements would be located underground and would not result in any visual impacts to the project area. Therefore, because the sewer improvements would be underground upon installation, and because the proposed fence and lighting improvements would be similar in height, scale, and materials to the existing fencing and lighting improvements at the Detention Center, the revised project would not result in a substantial change in the visual character and quality of the developed site, compared to the originally approved project. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. Under the revised project, 11 25-foot-tall pole -mounted lights would be installed along the proposed fence line that would form the eastern project site boundary with the Detention Center. These lights would be staggered with the existing perimeter lighting located along the fence line that surrounds the Detention Center. While there would be an increase in the number of overhead lights surrounding the Detention Center, the area is well lit under existing conditions with existing perimeter lights and field lights. Therefore, the project revisions would not result in installation of a new lighting source that would be out of character with the existing conditions of the area or that would adversely affect daytime or nighttime views. In addition, revisions associated with installation of the proposed sewer line would not result in light or glare impacts. As with the approved project, the revised project would comply with the City's existing outdoor lighting restrictions to prevent off -site light spillage and glare. Specifically, the project revisions would be required to adhere to the Conditions of Approval adopted for the project in June 2022, which includes condition PL-18, which states that "all lighting shall be directed down and shielded from neighboring uses" and that the project applicant "shall prepare a photometric study ... that demonstrates that no light will spill over property lines." Therefore, the proposed project revisions would result in no difference in impact on day or nighttime views due to a new source of light or glare, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Air Quality The Certified EIR for the approved project addressed air quality impacts in Section 3.2 of the Draft EIR. As stated in the Certified EIR, the original project would not cause any significant impacts related to air quality with implementation of several mitigation measures. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The Findings for each of the thresholds evaluated in the Certified EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not conflict with or obstruct implementation of the 2016 Air Quality Management Plan (AQMP) with the implementation of Mitigation Measures 31 MM 3.2-1 and MM 3.2-2. The approved project meets both criteria established by the South Coast Air Quality Management District (SCAQMD). The first criterion would be met as the project's long-term emissions would be below the localized significance thresholds, and construction emissions of criteria pollutants would be less than significant with the implementation of the mitigation measures mentioned above. Mitigation Measure 3.2-1 requires all off -road diesel -powered construction equipment greater than 50 horsepower to meet U.S. Environmental Protection Agency (USEPA)- certified Tier 4 emissions standards and all construction equipment to be outfitted with best available control technology (BACT) devices certified by the California Air Resources Board (GARB) during project construction. Mitigation Measure MM 3.2-2 restricts the size of haul vehicles during site preparation and grading. The second criterion would be met as the project was determined to be consistent with the General Plan land use policies and zoning standards, as well as the Regional Transportation Plan and Sustainable Communities Strategy (RTP/SCS). As the 2016 AQMP incorporated the same growth projections used for the General Plan and RTP/SCS, the project would be consistent with the projections included in the 2016 AQMP. Further, the project would implement all feasible air quality mitigation measures with the implementation of Mitigation Measures MM 3.2-1 and MM 3.2-2, described above. Finally, the project would not conflict with the land use planning strategies set forth in the RTP/SCS. As the criteria established by SCAQMD have been met, with the implementation of the mitigation measures mentioned above, the project would result in less -than -significant impacts involving a conflict with the AQMP. b. The approved project would not result in a cumulatively considerable net increase of criteria pollutants for which the project region is non -attainment under an applicable federal or state ambient air quality standard, with implementation of Mitigation Measures MM 3.2-1 and MM 3.2-2. Without the implementation of these mitigation measures, the construction of the approved project would exceed the regional threshold established by SCAQMD for nitrogen oxides (NO.), a criteria pollutant. The implementation of these mitigation measures, described above, would result in a reduction of NO. emissions to below SCAQMD regional thresholds. Operation of the approved project would result in generation of criteria air pollutants below all SCAQMD regional thresholds. c. The approved project would not expose sensitive receptors to substantial pollutant concentrations during the grading phase, with implementation of Mitigation Measures MM 3.2-1 and MM 3.2-2. Impacts to sensitive receptors were evaluated using Local Significance Thresholds (LSTs) established by SCAQMD. Without implementation of these mitigation measures, the construction of the proposed project would result in an exceedance of LSTs for particulate matter (PMIo and PM2.5). The implementation of mitigation measures MM 3.2-1 and MM 3.2-2 would reduce these emissions to below the SCAQMD LSTs. Operation of the approved project would not result in stationary or mobile sources that would exceed LSTs, and impacts would be less than significant. Further, background levels of carbon monoxide (CO) are not high enough to result in a CO hotspot due to the approved project's added vehicular traffic. 32 d. The approved project would not result in other emissions (such as those leading to odors) adversely affecting a substantial number of people. Although construction activities could generate detectable odors, these odors would be short-term and would cease upon completion of construction. In addition, the approved project would be required to comply with state regulations minimizing the idling time of construction equipment, which would further reduce the detectable odors from heavy-duty equipment exhaust. The approved project would also be required to comply with SCAQMD regulations to reduce odor impacts from reactive organic gas (ROG) emissions during architectural coating. No other types of emissions, beyond those described above, would be generated by the approved project. Comparative Analysis for Proposed Project Revisions a. The revised project would potentially change pollutant concentrations during the mass grading phase due to a very slight increase in the total volume of earth movement associated with minor grading to prepare a flat surface in between the existing and proposed fence line (to provide an access road for vehicles), as well as minor earthwork to excavate the bore and receiving pits for installation of the sewer line underneath Bouquet Creek, described further below. The Certified EIR-recommended Mitigation Measures MM 3.2-1 and 3.2-2 would also be implemented under the revised project and would require all off -road diesel -powered construction equipment to meet USEPA- certified Tier 4 emissions standards and to be outfitted with BACT devices certified by GARB. Under the first criterion established by the SCAQMD related to causing or contributing to localized air quality violations or delaying the attainment of air quality standard or interim emissions reductions specified in the AQMP, the revised project's long-term emissions would continue to be below the localized significance thresholds as discussed under subsections b and c below. The revised project would also meet the second criterion established by SCAQMD concerning whether the revised project exceeds assumptions utilized in preparing forecasts present in the AQMP. The revised project would remain consistent with the General Plan land use policies, zoning standards, and the RTP/SCS as the residential land uses proposed by the approved project are not changing under the revised project, and because the revised project's proposed fencing and lighting improvements located on the project site's boundary with the Detention Center to the east are consistent with existing improvements at the Detention Center. In addition, the revised project would not increase or change the residential development already determined to be consistent with the types, intensity, and patterns of land use envisioned for the site vicinity in the RTP/SCS in the Certified EIR and the 2022 EIR Addendum. Lastly, the revised project would still be consistent with the land use projections included in the 2016 AQMP because the SCAQMD incorporated the land use projections in the RTP/SCS into the 2016 AQMP. Further, the revised project would continue to implement all feasible air quality mitigation measures, as described more fully below. There are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. 33 b. The revised project may result in extremely minor changes to the amount of emissions during the mass grading phase. The approved project would involve a total grading volume of approximately 2,070,000 cubic yards (cy), which was updated by the 2022 project revisions to a total grading volume of approximately 2,800,000 cy. The revised project would involve minor grading of an already relatively flat area to prepare an access road between the existing and proposed fence line on the project site's boundary with the Detention Center to the east. Other earthwork associated with the revised project would be limited to the bore and receiving pits excavated to install the proposed sewer line. These pits would each be 10 feet wide by 30 feet long by 10 feet deep. This would result in excavation of approximately 6,000 cubic feet (or 3,000 cubic feet for each pit), which is approximately 220 cy of soil. This represents a negligible percentage of the total project grading at approximately 0.008 percent of the project's the total grading volume (2,800,000 cy). Even when considering the limited grading associated with the proposed pathway between the existing and proposed fence lines, the revised project's additional grading would be negligible in context of the project's total grading volume. Therefore, the revised project would not cause significant changes in the primary sources of construction emissions. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. As with the approved project, impacts would be reduced to less than significant with implementation of Mitigation Measures MM 3.2-1 and 3.2-2, which would require all off - road diesel -powered construction equipment to meet USEPA-certified Tier 4 emissions standards and to be outfitted with BACT devices certified by GARB. As the revised project would result in a minimal change to the total grading volume proposed by the project, construction of the revised project would be essentially the same as the approved project. As such, the revised project would not substantially increase short- term construction emissions. Further, the revised project would not result in an increase in the capacity or use of the Detention Center, long term emissions would be similar to those evaluated by the Certified EIR. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. The revised project would not cause a change in other emissions (such as those leading to odors). Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Biological Resources The Certified EIR for the approved project addressed biological resource impacts in Section 3.3 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to biological resources with implementation of several mitigation measures. Further, the revised 2022 project EIR Addendum determined that, with 34 implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. In short, the EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would remove habitat that supports rare plant species (such as slender mariposa lilies) and sensitive animal species (10 sensitive animal species that could potentially occur on the project site). Slender mariposa lilies were identified primarily in the southeastern and southwestern portions of the project site, with 320 slender mariposa lilies being impacted by the new section of Bouquet Canyon Road. While not federally- or state -listed as endangered or threatened, they are considered rare. With implementation of preservation activities identified in Mitigation Measure MM 3.3-1, which includes replacement, payment into a mitigation bank, and/or preservation of land supporting slender mariposa lilies, the project impacts would be reduced to less than significant. Of the 10 animal species that could potentially occur on the project site, three have a low potential to occur, one has a moderate potential to occur, four have a high potential to occur, and two are presumed absent. Impacts would be less than significant to those animals with a low or moderate potential to occur and to the coastal California gnatcatcher, which is presumed absent, and no mitigation measures would be required. Of the species with a high potential to occur, coastal whiptail, coast horned lizard, loggerhead shrike, and San Diego black -tailed jackrabbit are highly mobile and would be expected to disperse to undeveloped land to the east of the proposed project. Loggerhead shrike eggs and young, however, are protected under the Migratory Bird Treaty Act, discussed further below and addressed in Mitigation Measure MM 3.3-4. While burrowing owl was not found on -site, the project site does provide suitable habitat for this species throughout the project site with burrows that could potentially be used by burrowing owl located primarily in the central, western, and southwestern portions of the site. As such, Mitigation Measure MM 3.3-2 would be required, which includes a take avoidance survey and, if required, a Burrowing Owl Protection and Relocation Plan. If burrowing owl is observed during this survey, active burrows shall be avoided. With the implementation of Mitigation Measures MM 3.3-1, 3.3-2, and 3.3-4, the approved project would not result in significant impacts to species identified as a candidate, sensitive, or special status species. b. The approved project would result in permanent impacts to 28.68 acres of native plant - dominated habitat and 55.55 acres of habitat dominated by non-native species and previously disturbed areas. The elderberry savanna and southern willow scrub/giant reed stand habitats on the project site are considered sensitive natural communities by the California Department of Fish and Wildlife (CDFW) (totaling 1.26 acres) and would be permanently impacted by the proposed project. The elderberry savanna was observed in the northern portion of the project site. The southern willow scrub/giant reed stand was observed in the western portion of Bouquet Creek. However, both habitats are considered low quality due to their size and the presence of invasive species. Although southern willow scrub/giant reed stand is considered low -quality habitat, the 35 project would offset permanent impacts to 0.70 acre through compensatory mitigation for jurisdictional streambed impacts as outlined in Mitigation Measure MM 3.3-3, which requires the issuance of a Streambed Alteration Agreement by CDFW. Therefore, with implementation of appropriate mitigation measures, the approved project would have a less -than -significant adverse effect on riparian habitat or a sensitive natural community identified in local or regional plans, policies, regulations, or by CDFW or the U.S. Fish and Wildlife Service (USFWS). c. The approved project would result in 0.19 acre of permanent impacts and 0.46 acre of temporary impacts to non -wetland WUS. Permanent impacts would be concentrated on the western and eastern ends of Bouquet Creek within the project site. The remaining portion of Bouquet Creek would be temporarily impacted by the construction of a new flood control channel south of the natural Bouquet Creek channel on the project site. Temporary impact areas would be restored to pre -project contours following completion of construction. Mitigation Measure MM 3.3-4 would be required to offset permanent impacts. This measure requires the applicant to demonstrate that the appropriate regulatory permits have been issued by the United States Army Corps of Engineers (USAGE) and the Regional Water Quality Control Board (RWQCB). Further, Mitigation Measure MM 3.3-4 requires compensatory mitigation for permanent impacts at a ratio of no less than 1:1. With the implementation of Mitigation Measure MM 3.3-4, impacts to state or federally protected wetlands would be less than significant. d. The approved project is not part of a regional wildlife movement corridor, does not serve as a wildlife nursery site, and is not identified as being part of a local or regional corridor or linkage. The approved project would result in temporary impacts on the movement of terrestrial and avian wildlife through the project site during construction. Bouquet Creek does not provide a migratory fish corridor given existing barriers to wildlife movement upstream and downstream of the project site and the ephemeral nature of the creek. Although the majority of the stream would be recontoured to pre -project conditions following construction, the project may disturb or destroy active migratory bird nests and young protected by the Migratory Bird Treaty Act (MBTA) and, as such, requires implementation of a mitigation measure. Mitigation Measure MM 3.3-5 requires measures to reduce impacts by limiting work performed during bird nesting season. If construction activities must occur during nesting season for migratory birds and raptors, a qualified biologist shall perform a preconstruction survey and implement construction buffer zones, if required. With implementation of Mitigation Measure MM 3.3-5, the impacts to species protected under the MBTA would be less than significant. e. The project site contains 64 oak trees that are protected by the City of Santa Clarita's Oak Tree Preservation Ordinance. The approved project would remove 26 oak trees, subject 1 oak tree to major encroachment, subject 2 oak trees to minor encroachment, and preserve the remaining 35 oak trees. These oak trees are located in the northeastern, northwestern, and southwestern portions of the project site. Compliance with the City's Oak Tree Preservation Ordinance and Oak Tree Preservation Guidelines would reduce project -related impacts to protected oak trees to a less -than -significant level. 36 f. The approved project would not conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan as the project site is not located within such a plan area. As such, this threshold was not analyzed in the Certified EIR. g. The approved project would not affect a Significant Ecological Area as identified on the City of Santa Clarita SEA Delineation Map as the project site is not located within a Significant Ecological Area. As such, this threshold was not analyzed in the Certified EIR. Comparative Analysis for Proposed Project Revisions a. An addendum to the approved project's biological technical report was prepared for the 2022 revised project and analyzed in the 2022 EIR addendum. This report, Addendum to the Biological Technical Report for the Bouquet Canyon Project, dated February 16, 2022, includes the revised project area, identifying it as "revised project area No. 6; Sewer Line." The addendum states that the revised project area where the sewer realignment and fencing/lighting improvements would take place supports riverwash and non-native vegetation, which are not suitable for the rare plant species analyzed in the report. This area does not support habitat for slender mariposa lilies or other rare plants. As such, under the revised project, the total impacts to slender mariposa lilies would remain at 453 individual lilies, as was proposed in the 2022 revised project. This represents a reduction in the total number of lilies impacted by the project by 9 individuals because the approved project was anticipated to impact 462 individual lilies. Moreover, the revised project would also be required to implement Mitigation Measure MM 3.3-1 with regard to preservation or replacement of slender mariposa lilies in other areas of the project site where mariposa lilies are found. The proposed mitigation plan is provided as Appendix A.2 of this Addendum. Therefore, the revised project would not result in an increase in the impact to rare plants and would remain consistent with the findings described in the Certified EIR with mitigation. In addition, the Addendum to the Biological Technical Report, development of the revised project would not result in a greater potential for sensitive wildlife species to occur within the project site. No suitable habitat for burrowing owl was detected during the biological survey performed for the proposed area of disturbance (i.e., the sewer line installation or fencing and lighting installation); however, the overall development site does provide some suitable habitat for burrowing owl. As such, as with the original project, the revised project would comply with mitigation measure MM 3.3-2 to avoid burrowing owls. Therefore, as with the approved project, with the implementation of the previously identified mitigation measures MM 3.3-1 and MM 3.3-2, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. 37 b. As detailed in the Addendum to the Biological Technical Report for the Bouquet Canyon Project, which was originally prepared for the 2022 addendum to the Certified EIR, the 2022 project revisions, which included the proposed project area (identified in the report as revised area No. 6, "Sewer Line"), resulted in a reduction of the permanent impacts of the original project by 5.62 acres of vegetation by reducing overall impacts to vegetated areas and removal of PA-1A. This updated project area analyzed in this report includes the proposed project area (accommodating the area to install the sewer line and the fencing and lighting proposed on the east side of the project site). Specifically, the Addendum to the Biological Technical Report states that revised project area number 6 (which encompasses the proposed project area) consists of non-native vegetation and ornamental vegetation, along with limited areas of river wash and mule fat scrub within Bouquet Creek. The report states that these vegetation communities and land uses do not provide suitable habitat for sensitive wildlife species previously analyzed in the Certified EIR to have a potential to occur on the project site. Further, these vegetation communities are not considered sensitive by CDFW. The proposed project revisions would include construction of a new fence and light poles, as well as installation of a sewer line, connecting an existing sewer main to Bouquet Canyon Road to the north. The sewer line proposed would be installed with directional drilling and would not result in additional impacts to vegetation communities within or along Bouquet Creek. The construction of the fence and light grading that would create an access road between the existing and proposed fence lines would impact vegetation communities that are not considered sensitive by CDFW. Therefore, under the revised project, overall impacts to identified sensitive habitats (i.e., southern willow scrub/giant reed stand, elderberry savanna) would remain the same as the approved project and 2022 revised project. As with the approved project, the proposed project revisions would still implement Mitigation Measure MM 3.3-3 to secure a CDFW Streambed Alteration Agreement. Therefore, with the implementation of Mitigation Measure MM 3.3-3, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c. As with the approved project, the revised project would implement Mitigation Measure MM 3.3-3 to secure a CDFW Streambed Alteration Agreement and Mitigation Measure MM 3.3-4 with regard to issuance of a Clean Water Act Section 404 permit from USACE and a Clean Water Act Section 401 permit from RWQCB. As discussed in the Addendum to the Biological Technical Report for the Bouquet Canyon Project dated February 16, 2022 and included as Appendix A.1 of this Addendum, the 2022 project revisions resulted in a total reduction of 0.01 acre of permanent impacts (from 0.19 acre to 0.18 acre) to USACE jurisdictional waters when compared to the approved project analyzed in the Certified EIR. The proposed project area is included within this analysis and is represented in this total reduction in permanent impacts to jurisdictional waters when compared with the approved project. Further, the proposed sewer line realignment would be installed with directional drilling and would not result in additional impacts to jurisdictional streambeds regulated by the CDFW, USAGE, or RWQCB. Therefore, as with the approved project, impacts of the revised project with regard to jurisdictional 38 waters are considered less than significant pursuant to CEQA. In addition, the proposed fence and lighting improvements are not located within jurisdictional waters. Therefore, the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. As stated in the Certified EIR, while the approved project would result in temporary impacts on the movement of terrestrial and avian wildlife through the project site during construction, Bouquet Creek does not provide a migratory fish corridor given existing barriers to wildlife movement upstream and downstream of the project site and the ephemeral nature of the creek. The proposed project revisions involve a sewer line extension that crosses Bouquet Creek; however, the sewer line proposed would be installed with directional drilling and would not result in additional impacts to the streambed. The installation of the proposed fence line and grading of the access road between the proposed and existing fence lines would require removal of non-native and riverwash vegetation. Although nesting birds may be present in or around the project during construction, the revised project would be required to implement Mitigation Measure MM 3.3-5 to avoid disruption of active bird nests during construction. Therefore, with implementation of MM3.3-5, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. e. As provided in the Addendum to the Oak Tree Report for the Bouquet Canyon Project (February 16, 2022; Appendix A.2 of this Addendum), an oak tree survey conducted within the revised project area did not identify any oak trees that may be impacted by the proposed sewer main realignment or the proposed installation of fencing and lighting improvements. As with the approved project, the revised project would still comply with the City's Oak Tree Preservation Ordinance and Oak Tree Preservation Guidelines where applicable. Therefore, the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. f. The revised project would not cause conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other conservation plan as the project site is not located within such a plan area. Therefore, there are no material changes in circumstances, and the revised project would have no impact. g. The revised project would not result in changes that would affect a Significant Ecological Area as the project site is not located within a Significant Ecological Area, as identified in the City's General Plan Conservation and Open Space Element (CO-32). Therefore, there are no material changes in circumstances and the revised project would have no impact. Cultural Resources The Certified EIR for the approved project addressed cultural resource impacts in Section 3.4 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to cultural resources with implementation of several mitigation 39 measures. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not have an impact on a historical resource as no historical resources, as defined by CEQA Section 15064.5(a), are located within the project site. b. The approved project would potentially have an impact on archaeological resources. Although no archaeological resources were identified within the project site during cultural resources investigations, there have been a number of findings of such resources in the project vicinity, indicating a high potential to discover presently unknown resources during project excavation work. Further, the Chari/Suraco and Ruiz cemeteries are likely to be located within the project site in or near areas planned for development. The Chari/Suraco cemetery was indicated to occur in the western portion of the project site near PA-1, and the Ruiz cemetery was indicated to occur along the ridge planned for a recreation trail. With implementation of Mitigation Measure MM 3.4- 1, which includes development of an Archaeological and Native American Monitoring Program and addresses potential discovery of the Ruiz cemetery, and Mitigation Measure MM 3.4-2, which includes identification and avoidance of the Chari/Suraco cemetery, impacts would be reduced to less than significant. c. The approved project would potentially have an impact to significant cultural resources due to the likely presence of human remains. While no physical remnants of potential cemeteries were identified during site investigations, a location near PA-1 was identified as a likely location for the Chari/Suraco cemetery, and a location along the ridge planned for a recreational trail was identified as a likely location for the Ruiz cemetery. Implementation of Mitigation Measures MM 3.4-1 and MM 3.4-2, as described above, would reduce impacts to these cultural resources to less than significant. Comparative Analysis for Proposed Project Revisions a. The revised project now includes the installation of a new fence line and new light poles on the project site's eastern boundary with the Detention Center. As detailed in the Addendum to the Cultural Resources Survey and Assessment, dated February 2022, provided as Appendix B of this Addendum, there were no cultural resources identified during the surveys completed in the revised project area. Based on the results of the current study, no significant historical resources would be impacted by the revised project. As such, the revised project remains consistent with the findings documented in Section 3.4 of the Draft EIR. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, the revised project, would be required to implement Mitigation Measure MM 3.4-1, which would require development of an Archaeological 40 and Native American Monitoring Program. As such, similar to the approved project, impacts related to archaeological resources as a result of the revised project would be less than significant with implementation of Mitigation Measures MM 3.4-1 and MM 3.4- 2. c. As with the approved project, the revised project, would implement Mitigation Measure MM 3.4-1, which would require development of an Archaeological and Native American Monitoring Program. Therefore, similar to the approved project, the revised project's impacts due to the presence of human remains would be less than significant with implementation of Mitigation Measures MM 3.4-1 and MM 3.4-2. Energy The Certified EIR for the approved project addressed energy consumption impacts in Section 3.5 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to energy consumption, and no mitigation would be required. Further, the revised 2022 project EIR Addendum determined that the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not result in wasteful, inefficient, or unnecessary consumption of energy resources. Energy efficiency and conservation during construction would be achieved through compliance with federal and state standards and regulations, such as the state idling requirement that equipment not in use for more than five minutes be turned off and engine emissions standards. There are no unusual project characteristics that would necessitate the use of construction equipment that would be less energy efficient than at comparable construction sites in the region or state. The approved project would adhere to all federal, state, and local requirements for energy efficiency. Further, the approved project would not result in any unusual characteristics that would result in excessive long-term operational fuel consumption, or in the inefficient, wasteful, or unnecessary consumption of building energy, and, as such, a less than significant impact would occur. b. The approved project would not conflict with or obstruct a state or local plan for renewable energy or energy efficiency, such as Title 24 of the California Code of Regulations and the California Green Building Standards (CALGreen) code, and a less - than -significant impact would occur. Comparative Analysis for Proposed Project Revisions a. As with the approved project, the revised project would comply with federal and state standards and regulations related to energy conservation during construction and operation. Further the revised project would not result in any unusual characteristics that would necessitate the use of construction equipment that would be less energy efficient than at comparable construction sites in the region or state. Further, the pole mounted perimeter lights proposed for installation would be energy efficient LEDs and 41 would not result in a substantial increase in operational energy consumption when compared with the approved project's residential land uses or the Detention Center's existing lighting. In short, the long-term operational energy consumption associated with the revised project's lighting units would not represent a substantial increase in the residential energy consumption considered as part of the approved project. Therefore, the revised project would not result in material changes in the project's long-term operational fuel consumption, or in the inefficient, wasteful, or unnecessary consumption of energy. In addition, construction activities associated with the revised project would not substantially increase the fuel consumption previously identified for the approved project given the relatively small increase in grading activities discussed above. Given that the revised project's grading activities would represent approximately 0.008 percent of the total project grading volume, the revised project would have effectively the same construction energy consumption as evaluated in the Certified EIR and the 2022 EIR addendum. The Certified EIR concluded the construction activities associated with the approved project would increase the Countywide fuel consumption by 0.0307 percent. The 2022 project EIR addendum determined that the 2022 project revisions would then increase county -wide fuel consumption to 0.0415 percent (an increase of 0.0108 percent). In short, as with the approved project, the revised project would have a minimal effect on the local and regional energy supplies (e.g., automobile fuel) during construction. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, the revised project would not conflict with or obstruct a state or local plan for renewable energy or energy efficiency, such as Title 24 and CALGreen code because the revised project would be required to comply with Title 24 and CALGreen standards and would utilize electricity provided by Southern California Edison that would be composed of 50 percent renewable energy sources by 2030. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Geology and Soils The Certified EIR for the approved project addressed geology and soil impacts in Section 3.6 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to geology and soil with implementation of a mitigation measure. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. 42 Findings Regarding Impacts of Originally Approved Project ad. No State -mapped earthquake faults occur within the project site. An indication of a fault rupture was identified during initial site geotechnical investigations; however, as provided in the Certified EIR, a subsequent investigation found that the project site is not transected by any active fault traces. Therefore, structure setbacks or restrictions related to fault activity would not be required, and there would not be a significant impact involving construction within or along an active fault. a.ii. The approved project would not cause substantial adverse effects involving strong seismic ground shaking. Compliance with the seismic design criteria required by the Santa Clarita Municipal Code would reduce potentially seismically induced ground shaking impacts to less than significant. a.iii. The approved project would remove and replace unstable materials that could result in substantial adverse effects involving seismic -related ground failure, including liquefaction. Compliance with the Santa Clarita Municipal Code and the recommendations in the approved project's geotechnical report would sufficiently alleviate on -site liquefaction hazards. a.iv. The approved project's grading plan would remediate existing landslide conditions, and compliance with the Santa Clarita Building Code would ensure that the earthwork and slope stability measures are sufficient to reduce potential landslide hazards to less than significant. b. The approved project would include site clearance and grading activities that would expose soils to potential for erosion due to rainstorms and winds. Compliance with existing regulatory standards, including acquisition of an National Pollutant Discharge Elimination System (NPDES) Construction General Permit, would provide sufficient best management practices to prevent significant erosion impacts. The developed site under the approved project would reduce erosion potential and provide effective erosion controls over the long term, such that there would not be significant erosion impacts. c. The approved project would be located on land with a geologic unit or soil that is unstable and could potentially result in on -site landslide, subsidence, or liquefaction. Compliance with the provisions of the Santa Clarita Building Code and the design features identified in the approved project's geotechnical report would sufficiently alleviate the unstable soil conditions. Therefore, impacts would be less than significant. d. The approved project would be located on expansive soil. However, compliance with the Santa Clarita Building Code and the recommendations in the approved project's geotechnical report would mitigate potential impacts to a level of less than significant. e. The approved project would not involve the use of septic tanks or alternative wastewater disposal systems as all wastewater would be discharged to a sanitary sewer system. Therefore, there would be no impact. 43 f. Excavation associated with the approved project would disturb two geologic formations where important fossil resources have been discovered in the Santa Clarita Valley, Saugus and Castaic Formations. Field monitoring by a qualified paleontologist, as described in Mitigation Measure MM 3.6-1, would ensure that significant paleontological resources are not destroyed by excavation work. Although the approved project would partially alter a City -designated Significant Ridgeline in the western portion of the site, there are other General Plan -designated, significant ridgelines in the immediate vicinity of the project site, all of which are taller than the ridgeline on the project site. Therefore, this would be a less -than -significant impact. Comparative Analysis for Proposed Project Revisions ad. As previously discussed, the project site is not transected by any active fault traces. As with the approved project, the revised project would not result in changes that would induce any movement or rupture of a known earthquake fault. As such, similar to the approved project, the revised project would not require structure setbacks or restrictions related to fault activity, and there would not be a significant impact involving construction within or along an active fault. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. a.ii. As with the approved project, the revised project would not affect the project site's existing geologic conditions and would not result in changes that would directly or indirectly cause adverse effects related to strong seismic ground shaking. Further, as with the approved project, the revised project would still be required to comply with the seismic design criteria provided in the Santa Clarita Municipal Code . Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. a.iii. The northern and central portions of the project site along the canyon bottom lie within a designated Liquefaction Hazard Zone. The revised project's proposed fencing, lighting, and sewer line improvements are located within this Liquefaction Hazard zone. The approved project and the 2022revised project were determined to reduce the potential detrimental effects of liquefaction by implementing various strategies, including grading/earthwork that removes and replaces potentially liquefiable soils with non -liquefiable fill soils, in situ ground improvement methods that reduce liquefaction potential, designing structural foundations in recognition of potential liquefaction -induced settlement, or a mixture of these strategies. These strategies would still be implemented by the revised project, where applicable. As with the approved project, this standard regulatory compliance process would reduce the revised project's potential impacts associated with liquefiable soils to a less -than -significant level. Therefore, there are no material changes in circumstances, and the revised 44 Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. a.iv. As with the approved project, the revised project would still comply with City requirements and applicable design criteria per the California Building Code. As detailed in geotechnical memoranda from LGC Geotechnical, Inc., dated October 20, 2021, and April 12, 2022 and included as Appendix C of this Addendum, the approved and 2022 revised project would implement strategies so that remedial grading would be performed in slope areas where adversely oriented bedding planes exist. This remedial grading would remove the adversely oriented bedrock and replace it with engineered fill materials. The cut grading associated with the approved and 2022 revised development would likely remove some, if not all, of the existing landslide materials. If the landslide materials are not removed by cut grading, then they would be overexcavated and replaced with engineered fill materials. Given the relatively small amount of additional grading required to prepare the access road between the existing and proposed fence lines, and to excavate the bore and receiving pits for installation of the sewer line, the revised project's impacts related to landslides would be similar to those already analyzed in the Certified EIR and the 2022 EIR addendum. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. The revised project would include minimal additional grading limited to preparation of an access road between the existing and proposed fence lines on the east side of the project site, as well as excavation of the bore and receiving pits for installation of the sewer line. As with the approved project, the revised project would be required to comply with regulatory standards that would provide sufficient measures to prevent significant erosion impacts during construction, such as obtaining the NPDES Construction General Permit. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c. The northern and central portions of the project site are susceptible to liquefaction, while the western and southern portions of the project site are susceptible to landslides and settlement due to consolidation of native soils and artificial fill. As with the approved project, the revised project would comply with the Santa Clarita Municipal Code and the design features and recommendations provided in the project site -specific geotechnical report. Furthermore, at buildout, the revised project would not create a new expanse of impervious surfaces that would be anticipated to generate excessive stormwater. Therefore, similar to the approved project, the revised project would have less -than -significant effects associated with the site's location on a geologic unit or soil that is unstable, or that would become unstable as a result of development. d. As with the approved project, the revised project would be required to comply with the Santa Clarita Municipal Code. Therefore, as with the approved project, although the 45 project would be located on expansive soil, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. e. As with the approved project, the revised project would not result in the use of septic tanks or alternative wastewater disposal systems. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. f. As with the approved project, the revised project would involve limited excavation associated with the installation of the fence and light poles, as well as the bore and receiving pits, which has the potential to yield previously undiscovered unique or significant paleontological resources. Similar to the approved project, with implementation of Mitigation Measure MM 3.6-1, the revised project would result in less -than -significant impacts to paleontological resources. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Greenhouse Gas Emissions The Certified EIR for the approved project addressed greenhouse gas (GHG) emissions impacts in Section 3.7 of the Draft EIR. As stated in the Certified EIR, the original project would not cause any significant impacts related to greenhouse gas emissions and no mitigation would be required. Further, the revised 2022 project EIR Addendum determined that the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would generate GHG emissions consisting of construction sources, area sources, and mobile sources. Indirect project -related sources of GHGs consisted of energy consumption, solid waste, and water demand. The approved project's total annualized GHG footprint, amortized over the lifetime of a project (assumed to be 30 years), would result in less -than -significant environmental effects. b. The approved project would not conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of GHGs. This includes consistency with CARB's 2017 Scoping Plan, the Southern California Association of Government's (SCAG's) 2016-2040 RTP/SCS, and the Santa Clarita General Plan. Comparative Analysis for Proposed Project Revisions a. The revised project would result in a minor increase in grading as compared with the approved project and the 2022 revised project. However, this increase in grading, as discussed above, would be limited to the bore and receiving pits excavated to install the 46 proposed sewer line and would result in excavation of approximately 6,000 cubic feet (or 3,000 cubic feet for each pit), which is approximately 220 cy of soil. This represents a negligible percentage of the total project grading at approximately 0.008 percent of the project's the total grading volume (2,800,000 cy). Even when considering the limited grading associated with the proposed pathway between the existing and proposed fence lines, the revised project's additional grading would be negligible in the context of the project's total grading volume. Further, the grading required for the project would involve an excavator and a guided bore machine, which are similar to construction equipment already anticipated to be used during construction of the approved project. Given the limited construction and grading activities associated with the revised project, the overall revised project would have a total annualized GHG footprint that would be similar to the approved project and the 2022 revised project and would, therefore, result in less -than -significant environmental effects. Therefore, there are no material changes in circumstances, and the revised Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, the revised project would be consistent with applicable plans, policies or regulations adopted for the purpose of reducing GHG emissions. Specifically, the revised project would remain consistent with the General Plan land use policies, zoning standards, and the RTP/SCS because the revised project site's land use designations in the General Plan and identical corresponding zone district classifications, would remain the same as the approved project. Therefore, the revised project is considered to be consistent with the General Plan land use policies and zoning standards for the project site. In addition, the revised project would be consistent with the types, intensity, and patterns of land use envisioned for the site vicinity in the RTP/SCS and, therefore, would not conflict with the land use planning strategies set forth in the RTP/SCS. For these reasons, the revised project would be consistent with applicable plans, policies or regulations of CARB's 2017 Scoping Plan, SCAG 2016-2040 RTP/SCS, and Santa Clarita General Plan adopted for the purpose of reducing GHG emissions.' Hazards and Hazardous Materials The Certified EIR for the approved project addressed hazards and hazardous materials impacts in Section 3.8 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to hazards and hazardous materials with implementation of mitigation measure MM 3.8-1. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe ' The analysis in the approved project Certified EIR was prepared prior to adoption of SCAG's 2020-2045 RTP/SCS (Connect SoCal). Therefore, this analysis focuses on consistency with the 2016-2040 RTP/SCS. Regardless, the revised project would be consistent with the types, intensity, and patterns of land use envisioned for the site vicinity in the 2020-2045 RTP/SCS and would not conflict with the land use strategies identified in this plan. 47 environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project includes grading and development around an existing abandoned/plugged oil well located along the proposed Bouquet Canyon Road alignment. The approved project would maintain sufficient ground cover above the existing abandoned/plugged oil well and sufficient space for access by a well rig and related equipment in the event that a future leak triggers a need to re -abandon the well to current standards as determined by the Geologic Energy Management Division, formerly the Division of Oil, Gas, and Geothermal Resources. Further, implementation of Mitigation Measure MM 3.8-1 requires the project applicant to test the oil/gas well and the soils around the oil/gas well prior to the issuance of a grading permit and for any contaminated soil to be disposed of in accordance with local, state, and federal laws. With implementation of this mitigation measure, impacts would be less than significant. b. The approved project would be designed to comply with the Los Angeles County Fire Code standards for development in a Very High Fire Hazard Severity Zone and would implement construction phase mitigation measures to reduce the potential for accidental fires from various construction ignition sources and ensure adequate emergency access. As detailed in Section 3.15, Wildfire, of the Draft EIR, Mitigation Measure MM 3.15-1 requires the development of a Construction Fire Prevention Plan; Mitigation Measure MM 3.15-2 requires the construction contractor to ensure the implementation of all construction -phase flammable vegetation removal, fuel modification, and irrigation systems; and Mitigation Measure MM 3.15-3 requires the development of an Emergency Vehicle Access Plan. The City's existing emergency response and evacuation procedures are sufficient to manage emergency evacuation circumstances that could occur due to wildland fires in the project area. With implementation of these designs and mitigation measures, impacts related to wildland fire hazards would be less than significant. Comparative Analysis for Proposed Project Revisions a. The revised project's grading activities would incrementally increase the total quantities by approximately 0.008 percent, when compared to the 2,800,000 cy of earthwork proposed by the 2022 revised project. Further, the revised project would adhere to Mitigation Measure MM 3.8-1 to test the identified abandoned oil/gas well prior to the issuance of a grading permit. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, the revised project would be designed to comply with the Los Angeles County Fire Code standards for development in a Very High Fire Hazard Severity Zone and would implement construction phase mitigation measures to reduce the potential for accidental fires from various construction ignition sources and ensure adequate emergency access. As with the approved project, the revised project would reduce potential impacts related to wildland fire hazards to a less -than -significant level 48 with implementation of Mitigation Measures MM 3.15-1 through 3.15-3. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Hydrology and Water Quality The Certified EIR for the approved project addressed hydrology and water quality impacts in Section 3.9 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to hydrology and water quality, and no mitigation would be required. Further, the revised 2022 project EIR Addendum determined that the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would generate a variety of potential stormwater pollutants. However, compliance with existing regulatory standards, such as requirements for implementation of a Stormwater Pollution Prevention Plan (SWPPP) and an Urban Stormwater Mitigation Plan (USMP), would ensure that the approved project would not violate any water quality standards or waste discharge requirements or otherwise substantially degrade the quality of surface water or groundwater. Compliance with these regulatory standards would reduce potential stormwater pollutants to a less -than - significant level. b. The approved project would not decrease groundwater supplies or interfere substantially with groundwater recharge such that the project would impede sustainable groundwater management of the basin. There is no groundwater production occurring at the project site, and proposed excavations would not encounter groundwater. Further, the City requires implementation of a USMP, which includes BMPs and LID design principles to lessen water quality impacts. The portion of Bouquet Creek within the project site would be maintained as a natural (unpaved and vegetated) drainage course and would continue to provide groundwater recharge as it does today. Therefore, while the project would create new impervious surfaces throughout the site, where none exist today, a majority of the site's drainage area (approximately 72%) would consist of pervious surfaces, comprised of vegetated slopes, landscaped community open space areas, private yards, parkways, recreation turf areas, etc., where infiltration would occur during rainstorms. the project would not contribute to depletion of groundwater or interfere with recharge of a managed groundwater supply source. Therefore, impacts would be less than significant. c.i. The approved project would alter the existing drainage pattern of the project site or the project vicinity, including through the alteration of the course of a stream or river or through the addition of impervious surfaces. However, the approved project would not alter the existing drainage pattern in a manner that would result in substantial erosion or siltation on- or off -site. The approved project would comply with Construction Activity Stormwater Measures established by the City to ensure retention of on -site 49 sediments and erosion control from slopes. Additionally, the approved project would implement a SWPPP, which includes BMPs, erosion control measures, and a USMP, which includes management of stormwater runoff. Further, Bouquet Creek would be retained in its natural contours following construction, a storm channel would be constructed that would prevent erosion and siltation during peak storm flows, and stormwater in natural areas would be collected in debris basins prior to entering the storm drain system. Finally, the approved project includes impervious surfaces and extensive landscaping, which would eliminate and reduce, respectively, erosion in these areas. Therefore, impacts would be less than significant. c.ii. The approved project would alter the existing drainage pattern of the project site or the project vicinity, including through the alteration of the course of a stream or river or through the addition of impervious surfaces. However, the approved project would not alter the existing drainage pattern in a manner that would substantially increase the rate or amount of surface water runoff, resulting in flooding on- or off -site. As mentioned previously, an engineered storm drainage system is proposed to provide enhanced flood control protection along Bouquet Creek. Further, in compliance with Los Angeles County Guidelines, on -site systems carrying stormwater runoff would meet design requirements to accommodate a 25-year storm event or a 50-year storm event. Compliance with this requirement and implementation of the drainage system would avoid significant flooding impacts. Therefore, impacts would be less than significant. c.iii. The approved project would alter the existing drainage pattern of the project site or the project vicinity, including through the alteration of the course of a stream or river or through the addition of impervious surfaces. However, the approved project would not alter the existing drainage pattern in a manner that would create or contribute to surface water runoff that would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. As mentioned previously, the approved project would comply with the City's and County's requirements to manage stormwater runoff. This compliance includes the installation of stormwater management and treatment systems throughout the project site. This system includes channelization of existing floodplain conditions along Bouquet Creek in the northern portion of the project site. During design year storm conditions, runoff from the new flood control channel would not result in flows that would exceed the capacity of the existing downstream channel segment that flows to the Santa Clara River. Further, compliance with the City's requirements would include implementation of treatment control best management practices (BMPs), which would ensure the approved project would not result in substantial additional sources of polluted runoff. As such, impacts would be less than significant. d. The approved project would not risk release of pollutants due to inundation in a flood hazard, tsunami, or seiche zone. The project site is not located within or adjacent to areas exposed to tsunami events. Given the distance between the project site and the nearest location where a seiche could occur, Bouquet Dam/Reservoir, it has been determined that the potential for substantial adverse impacts related to inundation as a result of seiche would be less than significant. Finally, while the northern portion of the 50 project site immediately adjacent to Bouquet Creek is designated by the Federal Emergency Management Agency (FEMA) as a high risk/special flood hazard area, the approved project would provide enhanced flood control protection, specifically the proposed flood control channel, that would eliminate much of the existing floodplain conditions in the area. The approved project would involve a request to FEMA to remove the northern portion of the project site north and south of Bouquet Creek from the FEMA Flood Zone A designation upon completion of the channel improvements. Therefore, upon completion of the approved project, impacts would be less than significant. e. The approved project would not conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan. The approved project would be subject to the requirements of the NPDES, which includes preparation and implementation of an SWPPP, and would comply with City requirements for stormwater during construction and operation. While the Santa Clarita Valley Groundwater Sustainability Agency has not established a Groundwater Sustainability Plan, the approved project would not interfere with groundwater or groundwater recharge, as discussed previously. Therefore, impacts would be less than significant. Comparative Analysis for Proposed Project Revisions a. Although the revised project would not result in a substantial amount of additional grading, as compared with the total grading volume proposed by the 2022 revised project, the revised project would still comply with existing regulatory standards, including requirements for implementation of an SWPPP and a USMP, to ensure that development would not violate any water quality standards or waste discharge requirements or otherwise substantially degrade the quality of surface water or groundwater. A USMP, which includes the proposed sewer main installation considered as part of the revised project, was prepared on March 7, 2022, and is provided as Appendix D of this Addendum. Similar to the approved project, compliance with these regulatory standards would reduce potential stormwater pollutants to a less than significant level. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As with the approved project, there is no groundwater production occurring at the project site, and proposed excavations under the revised project would not encounter groundwater considering that the bore and receiving pits required for installation of the proposed sewer line are only 10 feet deep. In addition, similar to the approved project, while the revised project would increase the amount of impervious surfaces on -site through installation of the proposed fence line, lights, and access road (unpaved and covered with decomposed granite), the proposed drainage areas would still allow infiltration during rainstorms. Accordingly, similar to the approved project, impacts of the revised project on groundwater resources would be less than significant. Therefore, there are no material changes in circumstances, and the revised Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. 51 c.i. As with the approved project, the revised project would be required to comply with standard BMPs to reduce the potential for significant erosion or siltation to occur during construction. During operation, the revised project, as with the approved project, would utilize installed stormwater management and treatment systems to manage stormwater from the impervious surfaces elsewhere on the project site, and the improved channel and proposed debris basins that were part of the 2022 revised project would prevent stormwater discharge from causing sedimentation or siltation. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c.ii.As with the approved project, the revised project would not alter the existing drainage pattern in a manner that would substantially increase the rate or amount of surface water runoff, resulting in flooding on- or off -site. Similar to the approved project, compliance with County requirements and implementation of the drainage system would avoid significant flooding impacts, and impacts would be less than significant. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c.iii. As with the approved project, the revised project would comply with the City's and County's requirements to manage stormwater runoff, including installation of stormwater management and treatment systems throughout the project site, as provided in the revised project's USMP. The proposed installation of the new fence line, light poles, and access road, as well as the proposed relocation of the sewer main would not result in a substantial increase in impervious surfaces. Specifically, the access road would consist of decomposed granite and would, therefore, not represent an increase in impervious surfaces that may cause runoff in the area. Therefore, the revised project would not result in a substantial change in the amount of impervious surfaces in the vicinity of the Detention Center when compared with existing conditions. In short, while the revised project includes added land areas, the revised project would not create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR d. As with the approved project, the project site is not located within or adjacent to areas exposed to tsunami events, and potential impacts under the revised project as a result of seiche would be less than significant based on the distance from Bouquet Dam/Reservoir. As with the approved project, the revised project would eliminate much of the existing floodplain conditions in the area. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. e. As with the approved project, the revised project would be subject to the NPDES and City requirements for stormwater during construction and operation. In addition, construction of the revised project would not reach depths where groundwater occurs. Similar to the approved project, the revised project would not conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan. The revised project would also be subject to the requirements of the NPDES, which includes preparation and implementation of a SWPPP, and would comply with City requirements for stormwater during construction and operation. Accordingly, impacts would be less than significant. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Noise The Certified EIR for the approved project addressed noise impacts in Section 3.10 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to noise with implementation of Mitigation Measure MM 3.10-1. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would generate temporary construction noise levels that could result in adverse impacts to the nearest existing homes. However, this impact would be reduced to less than significant through implementation of Mitigation Measure MM 3.10-1, which requires various construction control measures, including limiting times of haul truck deliveries and construction and equipping all construction equipment with properly operating and maintained mufflers. Operation of the approved project would not generate significant increases in local noise levels. Therefore, with implementation of Mitigation Measure MM 3.10-1, impacts would be reduced to less than significant. b. The approved project would not result in significant vibration impacts to nearby sensitive receptors, and impacts would be less than significant. Comparative Analysis for Proposed Project Revisions a. The revised project would be limited to installation of new fence along the project site's eastern boundary with the Detention Center to the east, installation of eleven new perimeter lights, and realignment of an existing sewer line. The construction equipment anticipated for the revised project would include an excavator and a bore machine, along with other machinery to clear existing vegetation for installation of the proposed 53 fence line. These modifications of the approved project would not result in any unusual characteristics that would substantially increase noise as further discussed below. Short -Term Construction Noise Impacts Similar to the approved project, pieces of construction equipment used during construction activities were determined to be the primary noise source during earthwork (use of a directional bore machine, excavators, dozers). The grading activity associated with the revised project would result in construction noise; however, the grading activity associated with the revised project would occur within approximately 300 feet of the closest existing sensitive receptors, comprising single-family homes located on the opposite side of Bouquet Canyon Road to the north. Under the approved project, the Certified EIR identified the closest existing sensitive receptor, a single-family home located on an inholding parcel which was not part of the original project, to be approximately 30 feet from the planned construction area. The 2022 revised project included this inholding parcel (aka the "donut hole" parcel APN 2812-008-002). The Certified EIR recommended Mitigation Measure MM 3.10-1, which would require all construction equipment to be equipped with properly operating and maintained mufflers; all stationary construction equipment located so that emitted noise is directed away from the nearest noise -sensitive receptors; all equipment staging located in areas farthest away from sensitive receptors; and limiting haul truck deliveries to the same hours specified for construction equipment (in accordance with Santa Clarita Municipal Code Section 11.44.080 Special Noise Sources — Construction and Building). Compliance with this mitigation measure was determined to reduce construction noise impacts at nearby sensitive receptors sufficiently to ensure that normal residential activities are not interfered with and impacts would be less than significant. Because the proposed grading activities would not occur closer to any noise -sensitive receptor than those identified in the Certified EIR and would be required to comply with Mitigation Measure MM 3.10-1, the revised project would also result in less -than -significant environmental effects. Mobile Noise The revised project would not change the noise levels generated by mobile sources. Overall, the total number of daily vehicle trips would not substantially change with implementation of the project revisions. The proposed project revisions would not result in an increase in the number of residential units and would not alter the capacity or operation of the Detention Center to the east. Therefore, the revised project would not result in significantly increasing noise levels along roadway segments analyzed in the previous Certified EIR or cause the existing noise levels under 65 dBA CNEL to exceed the land use compatibility "normally acceptable" community noise exposure level of 65 dBA CNEL. As with the approved project, the revised project would result in less -than - significant environmental effects as related to mobile noise. Stationary Noise Upon installation of the proposed project revisions (the proposed fence line, new perimeter lighting, and sewer main realignment), there would be no stationary noise 54 generated by the revised project. Specifically, the revised project would not increase the number of people using the project site, nor would it install equipment that would contribute to an increase in noise levels in the area. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determinations in the Certified EIR. b. The revised project would not result in different construction or operational vibration impacts as the approved project. As with the approved project, pieces of construction equipment used during construction activities were determined to be the primary vibration source during site preparation. Certain construction activities have the potential to result in varying degrees of temporary groundborne vibration, depending on the specific construction equipment used and the operations involved. Therefore, it could be assumed the grading activity and the use of the guided bore machine associated with the revised project would result in additional vibrations. However, the grading activity associated with the revised project would occur within approximately 300 feet of the closest existing sensitive receptors, single-family homes located on the opposite side of Bouquet Canyon Road to the north. Under the approved project, the Certified EIR identified the closest existing sensitive receptor, a single-family home located on an inholding parcel, which was not part of the approved project, to be approximately 30 feet distant from the planned construction area. Therefore, the activities specific to the revised project would further from the closest sensitive receptor, thereby resulting in lower levels of vibration than identified in the Certified EIR. The Certified EIR concluded vibration from construction activities experienced at the nearest sensitive receptor would be below the significance threshold (excessive human annoyance). Because the increased grading activities would not occur closer to any vibration -sensitive receptor than those identified in the Certified EIR, the revised project would result in less -than - significant environmental effects similar to the approved project. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Public Services The Certified EIR for the approved project addressed public services impacts in Section 3.11 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to public services, and no mitigation would be required. Further, the revised 2022 project EIR Addendum determined that the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would expand the amount of suburban residential land uses requiring fire department services in the project area. However, compliance with existing city, county, and state Fire Code standards pertaining to building design, internal circulation, fire flows, and emergency access would be sufficient to maintain desired levels of fire protection services to this area. No new or expanded fire station facilities would be required to address the approved project's impacts, and impacts would be less than significant. b. The approved project would expand the amount of suburban residential land uses in the Saugus area and affect the ability of the Los Angeles County Sheriffs Department (LASD) to maintain adequate service ratios in the area. However, the new and larger Santa Clarita Valley Sheriffs Station at 26201 Golden Valley Road opened for service in Fall 2021 and replaced the original station at 23740 Magic Mountain Parkway. This new station would allow for LASD to improve the levels of service. As such, no new or expanded LASD station facilities would be required, and impacts would be less than significant. c. The approved project would result in the addition of approximately 280 school -aged children that would attend schools that serve the project area. Payment of mandatory development impact fees to each affected school district would sufficiently mitigate the approved project's impacts involving additional student enrollment to a level of less than significant. d. The approved project would result in the addition of approximately 1,125 new residents to the City's population that could utilize local public parks and recreation facilities. Payment of parkland dedication in -lieu fees, as specified in the Santa Clarita Municipal Code, would offset the approved project's impact on the supply of public parkland to less than significant. Comparative Analysis for Proposed Project Revisions a. The proposed project revisions would not affect the project's location in a Very High Fire Hazard Severity Zone. As such, the revised project would implement design criteria relative to fire protection services and comply with all applicable building safety codes and regulations related to fire prevention and suppression. Furthermore, the revised project activities would not impact the 2022 revised project's road alignments, which improve emergency response and access to the project site and surrounding areas as compared with the approved project. Therefore, similar to the original project, the revised project would not require the provision of a new or physically altered Los Angeles County Fire Department (LACFD) facility. As such, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. The revised project would not result in an increase in the size or capacity of the Detention Center to the east, nor would it result in an increase in the amount of M wastewater generation. Rather, the revised project would provide additional security and perimeter lighting to the Detention Center, as requested by the County of Los Angeles, and would realign an existing sewer main to connect to sewer infrastructure within Bouquet Canyon Road to the north. Therefore, the revised project would not affect the project's location or design criteria relative to law enforcement/public safety services. Furthermore, the new and larger Santa Clarita Valley Sheriffs Station at 26201 Golden Valley Road opened for service in fall 2021 and replaced the original station at 23740 Magic Mountain Parkway. Therefore, the revised project would not require the provision of new or physically altered LASD facilities, and the revised Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c. The revised project would not change the number of proposed residential units and, thus, the total number of school age children expected to reside on -site is the same as was analyzed in the approved project and the 2022 revised project. Therefore, there are no material changes in circumstances, and the revised Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. The revised project would not change the number of proposed residential units and, thus, the total on -site population. As such, the revised project would not have an impact on the demand for public parks and recreational facilities by future project residents. Furthermore, payment of parkland dedication in -lieu fees as specified in the Santa Clarita Municipal Code would offset the revised project's less than significant impact on the supply of public parkland. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Transportation The Certified EIR for the approved project addressed transportation impacts in Section 3.12 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to transportation with implementation of several mitigation measures. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities, with the implementation of Mitigation Measures MM 3.12-1 through MM 3.12- 12, described below. The primary metric utilized by the City to evaluate performance of 57 the circulation system is level of service (LOS). As such, the approved project's effect on LOS determines whether the approved project would have a significant impact. Several intersections were found to be significantly impacted by the approved project. The following mitigation measures would be implemented to reduce these impacts to less than significant. MM 3.12-1 would improve the intersection at David Way and Old Bouquet Canyon East by: removing an existing traffic signal; closing David Way between Old Bouquet Canyon Road and Copper Hill Drive (to eliminate the south leg of the David Way and Copper Hill Drive intersection); constructing a new east leg of David Way at Copper Hill Drive intersection and connecting to Old Bouquet Canyon Road; constructing a median island to restrict left -turn movement (southbound left) from David Way to Copper Hill Drive and installing a stop sign at David Way. • MM 3.12-2 would improve the intersection at Benz Road and Copper Hill Drive by constructing a median island to restrict left -turn movement (northbound left) from Benz Road to Copper Hill Drive. • MM 3.12-3 would improve the intersection at New Bouquet Canyon Road and Old Bouquet Canyon Road East by installing a traffic signal. • MM 3.12-4 would require the project proponent to pay the project's fair share contribution to a collective set of improvements that would alter and improve traffic flow on Benz Road, Copper Hill Drive, Kathleen Avenue, David Way, and Bouquet Canyon Road. • MM 3.12-5 would improve the intersection at Bouquet Canyon Road and Vasquez Canyon Road by requiring the project proponent to pay the project's fair share (2%) of the cost of these improvements: addition of a northbound right -turn de -facto lane; addition of a dedicated westbound left -turn lane; and installation of a traffic signal with northbound and southbound split -phasing. • MM 3.12-6 would improve the intersection at New Bouquet Canyon Road and Old Bouquet Canyon Road West by requiring the project proponent to pay the project's fair share (25%) of the cost of the improvement to construct a median island to restrict left -turn movement (southbound left) from Old Bouquet Canyon Road to eastbound New Bouquet Canyon Road. • MM 3.12-7 would improve the intersection at Kathleen Avenue and Copper Hill Drive by requiring the project proponent to pay the project's fair share (2%) of the cost of these improvements: installation of a traffic signal; and widening of Copper Hill Drive from 2 lanes to 4 lanes from Benz to Kathleen. • MM 3.12-8 would improve the intersection at Golden Valley Road and Plum Canyon Road by requiring the project proponent to pay the project's fair share (8%) of the cost of the improvement to update corridor signal timing coordination, as needed, due to future cumulative traffic volumes. 58 • MM 3.12-9 would improve the intersection at Seco Canyon Road and Bouquet Canyon Road by requiring the project proponent to pay the project's fair share (42%) of the cost of these improvements: addition of a second southbound left -turn lane; addition of one eastbound right -turn lane; and addition of a third northbound through lane. • MM 3.12-10 would improve the intersection at Bouquet Canyon Road and Newhall Ranch Road by requiring the project proponent to pay the project's fair share (8%) of the cost of the improvement to add a third westbound left -turn lane. • MM 3.12-11 would improve the intersection at Golden Valley Road and Newhall Ranch Road by requiring the project proponent to pay the project's fair share (0.5%) of the cost of these improvements: extension of the median pocket from 300 to 500 feet plus taper; and update to the corridor signal timing coordination, as needed, due to future cumulative traffic volumes. • MM 3.12-12 would improve the intersection at New Bouquet Canyon Road and Old Bouquet Canyon Road East (Copper Hill) by requiring the project proponent to pay the project's fair share (5%) of the cost of these improvements: addition of a second northbound through lane; and addition of a second southbound through lane. The approved project was also determined be consistent with plans addressing the roadway, transit, bicycle, and pedestrian systems, such as One Valley One Vision and the City of Santa Clarita Transit Development Plan. Therefore, with implementation of Mitigation Measures MM 3.12-1 through MM 3.12-12, impacts would be less than significant. b. The approved project would not conflict or be inconsistent with CEQA Guidelines Section 15064.3(b). While project residents would likely have a higher average vehicle miles traveled (VMT) than the Citywide average, the approved project also proposed to realign Bouquet Canyon Road, which would shorten the trip length for commuters who utilize this roadway by approximately 0.25 mile. According to the Certified EIR, approximately 22,000 to 27,000 vehicles per day were forecast to utilize the segment of Bouquet Canyon Road proposed for realignment. The realignment would slightly offset the VMT of the residential component of the approved project, and impacts were determined to be less than significant. c. The approved project would not substantially increase hazards due to a geometric design feature or incompatible uses. According to the Certified EIR, project roadways, under the approved project, would be constructed in accordance with the City's design standards. The approved project also would include the realignment of Bouquet Canyon Road in accordance with the General Plan designation of a Secondary Highway. With the realignment, any existing design features that are hazardous would be corrected. Therefore, impacts would be less than significant. d. The approved project would potentially result in inadequate emergency access for PA- 1, PA-2, and PA-3, as well as inconsistency with the Santa Clarita General Plan Circulation Element Policy C 2.5.2, which requires new development to provide adequate emergency and/or secondary access for purposes of evaluation and emergency response. However, with implementation of Mitigation Measure MM 3.12- 13, which requires secondary access to these planning areas, impacts would be reduced to less than significant. Comparative Analysis for Proposed Project Revisions a. The revised project would not change the number of proposed residential units, and would, therefore, have no impact on daily and peak hour trip generation. As such, the revised project would not worsen the LOS impacts of the approved project prior to mitigation and would implement Mitigation Measures MM 3.12-1 through MM 3.12-12 similar to the approved project. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. The revised project would not change the number of proposed residential units. Accordingly, the proposed project revisions would not alter the alignment of Bouquet Canyon Road in the southern portion of the project site and would, therefore, not inhibit the potential reduction in VMT that this roadway realignment would generate. Therefore, similar to the approved project, the revised project would not conflict or be inconsistent with CEQA Guidelines Section 15064.3(b), and impacts would be less than significant. c. The revised project would not alter the design or location of the new alignment of Bouquet Canyon Road in the southern portion of the project site. As such, any existing design features that are hazardous will be corrected through implementation of the approved project. Furthermore, the revised project would not affect any other street improvements or related design criteria on the project. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. During construction, similar to the approved project, the revised project would prepare and implement a construction traffic management plan and, per Mitigation Measure 3.15-3, an Emergency Vehicle Access Plan, to ensure that emergency response efforts would not be significantly impeded in the event of a wildfire during construction. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Tribal Cultural Resources The Certified EIR for the approved project addressed tribal cultural resources impacts in Section 3.13 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to tribal cultural resources with implementation of Mitigation Measure MM 3.13-1. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised 60 project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The project site does not included resources currently listed or eligible for listing in the California Register or in a local register of historical resources. Therefore, the approved project would have no impact on tribal cultural resources associated with a known historic resource. b. The approved project is located within the ancestral tribal territory of the Fernandeno Tataviam Band of Mission Indians. Consultation with this tribal entity determined that they consider this site to be sensitive, and the City and applicant have agreed to implement Mitigation Measure MM 3.13-1, which provides construction control measures to prevent accidental damage or destruction to tribal cultural resources. With the implementation of this mitigation measure, impacts would be less than significant. Comparative Analysis for Proposed Project Revisions a. As previously discussed with regard to cultural resources, the project site does not included resources currently listed or eligible for listing in the California Register or in a local register of historical resources. As with the approved project, the revised project would not result in impacts to a known historic resource. Accordingly, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. The original project involved a total grading volume of approximately 2,070,000 cy, and the 2022 revised project increased the total grading volume to approximately 2,800,000 cy. The proposed project revisions would represent a negligible increase to this total grading volume by increasing the total by approximately 0.008 percent. Regardless, the revised project would result in the potential for tribal cultural resources to be impacted during grading and excavation activities. As documented in the Addendum to the Cultural Resources Survey and Assessment provided as Appendix B of this Addendum, the FTBMI was invited to participate in the survey for the revised project areas but were unable to do so. Nonetheless, the revised project would retain implementation of Mitigation Measure MM 3.4-1, which requires an Archaeological and Native American Monitoring Program, and Mitigation Measure MM 3.13-1, which further specifies the Native American monitoring process. Accordingly, the potential impacts would remain less than significant with implementation of the proposed mitigation measures. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Utilities and Service Systems The Certified EIR for the approved project addressed utilities and service systems impacts in Section 3.14 of the Draft EIR. As stated in the Certified EIR, the approved project would not 61 cause any significant impacts related to utilities and service systems, and no mitigation measures would be required. Further, the revised 2022 project EIR Addendum determined that, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would require water service provided by Santa Clarita Valley Water Agency's (SCV Water) Santa Clarita Water Division (SCWD). The development would generate a water demand of approximately 338.85 acre-feet per year. This would require construction of new on- and off -site water infrastructure to connect to the existing local water distribution lines maintained and operated by SCWD. However, neither construction nor operation of the approved project would require expansion of existing or construction of new water transmission infrastructure, and impacts would be less than significant. b. SCV Water would have sufficient water supplies to meet the approved project's water demand of 338.85 acre-feet per year during normal, dry, and multiple dry years. Therefore, impacts would be less than significant. c. The approved project would require annexation into the Los Angeles County Sanitation Districts to discharge wastewater into their sanitary sewer system for conveyance and treatment. Specifically, the approved project would discharge wastewater to the Los Angeles County Sanitation Districts' Bouquet Canyon Relief Trunk Sewer and then convey it to the Saugus and Valencia Water Reclamation Plants (WRPs) for treatment. The trunk sewer and the WRPs would have sufficient capacity to convey and treat the flows generated by the original project. Therefore, the project would not require construction of new or expanded wastewater collection or treatment facilities, and impacts would be less than significant. d. The approved project would require annexation into the Los Angeles County Sanitation Districts to discharge wastewater into its sanitary sewer system for conveyance and treatment. The approved project would generate an estimated 0.074 million gallons per day of wastewater, which would be conveyed to Saugus and Valencia WRPs. These WRPs have the capacity to treat the flows generated, and the existing infrastructure has the capacity to convey wastewater to these WRPs. Therefore, the approved project would not result in a determination by the wastewater treatment provider that it has inadequate capacity, and impacts would be less than significant. e. The approved project includes stormwater drainage facilities that would be designed to contain stormwater from a 100-year storm. Infiltration and biofiltration basins are designed to hold a greater capacity than the water quality volume required by the County of Los Angeles. As such, the approved project would not require new or expanded stormwater drainage facilities off -site. Therefore, impacts would be less than significant. RN f. The project area is already served by electricity, natural gas, and telecommunication service providers. As such, the approved project would require connections to existing infrastructure. No other modifications to existing off -site infrastructure facilities are anticipated as there is adequate electric and natural gas capacity and existing telecommunication services. Therefore, the approved project would not require construction or expansion of such utility facilities, and impacts would be less than significant. Comparative Analysis for Proposed Project Revisions a. As the revised project would not change the number of proposed residential units, the total water demand of the development would be the same as previously analyzed in the Certified EIR and the 2022 EIR Addendum. As with the approved project, neither construction nor operation of the revised project would require expansion of existing or construction of new water transmission infrastructure. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. The revised project would not change the number of proposed residential units, and thus, would not result in a change in the project's total water demand. As such, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. c. The revised project would not result a change in the number of residential units within the project, nor would the revised project change the operations of the existing Detention Center to the east. Thus, while the revised project would install a sewer main underneath Bouquet Creek, this sewer main is replacing an existing sewer main that would be abandoned in place. With no anticipated increase in the capacity of the Detention Center to the east, wastewater demand is anticipate to be the same as was previously analyzed in the Certified EIR and 2022 EIR Addendum. As such, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. The revised project would not change the number of residential units associated with the project, nor would the revised project change the operations of the existing Detention Center to the east. Thus, total wastewater generation would not change as a result of the revised project activities. As such, the WRPs serving the project site also would have the capacity to treat the flows generated by the revised project. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. e. The revised project would not result in substantial runoff from the newly developed areas as the new fence line and access road constructed as part of the revised project activities would not add a substantial amount of impervious surfaces to the project site. 63 Rather, the limited grading associated with construction of the access road, which would consist of decomposed granite, would not substantially alter drainage patters in the area. As with the approved project, peak rates of developed site runoff that flow into the existing municipal storm drainage network outside of the project site would be no more than under current conditions, as required under Los Angeles County Department of Public Works (LACDPW) design standards. Therefore, there are no material changes in circumstances, and the revised Project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. f. The project area is already served by electricity, natural gas, and telecommunication service providers. The revised project would not alter the need for or placement of energy or telecommunications infrastructure. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. Wildfire The Certified EIR for the approved project addressed wildfire impacts in Section 3.15 of the Draft EIR. As stated in the Certified EIR, the approved project would not cause any significant impacts related to wildfire with implementation of Mitigation Measures MM 3.15-1 through MM 3.15-3. Further, the revised 2022 project EIR Addendum determined that, with implementation of the mitigation measures included within the Certified EIR, the 2022 revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. The EIR findings for each of the thresholds evaluated in the Certified Final EIR are summarized below. Findings Regarding Impacts of Originally Approved Project a. The approved project would not conflict with an emergency response plan and would not have a significant effect on emergency evacuation efforts in the event of a major wildfire event as the City's existing emergency response system would be sufficient to address emergency evacuation scenarios. Therefore, impacts would be less than significant. b. The approved project would not exacerbate wildfire risks, and would therefore not create conditions that would expose project occupants to pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire. The project site exposure to wildland fire risks is the same as surrounding residential neighborhoods. Further, the approved project would replace the existing undeveloped landscape that is covered by flammable vegetation with nonflammable landscape materials, install a pressurized water system throughout the project area, construct an internal street network to accommodate access for emergency response vehicles, and construct new homes with fire- and ignition -resistant materials. As such, the impacts would be less than significant. c. The approved project would include fuel modification zones required by the LACFD, underground utilities, and an internal circulation network. These standard design 64 features would not result in temporary or ongoing adverse impacts to the environment. However, construction activities could accidentally ignite fires. Implementation of Mitigation Measures MM 3.15-1 through MM 3.15-3 would ensure construction activities impacts would be less than significant. Mitigation Measure MM 3.15-1 would require the development of a Construction Fire Prevention Plan. Mitigation Measure MM 3.15-2 would require the construction contractor to ensure the implementation of all construction -phase flammable vegetation removal, fuel modification, and irrigation systems. Mitigation Measure MM 3.15-3 would require the development of an Emergency Vehicle Access Plan to ensure access during construction. d. The approved project would not expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a result of runoff, post - fire slope instability, or drainage changes. All manufactured slopes would be built to factors of stability required by the City's building code, which would also improve stability of several existing slopes areas compared to current conditions, where grading is proposed. All such slopes would also be landscaped with fire resistant materials, thus reducing the vegetation fuel load and reducing chances that a wildfire would denude the slopes and create possible landslide or flooding conditions due to loose/bare slopes. Accordingly, the approved project would have less than significant impacts. Comparative Analysis for Proposed Project Revisions a. The revised project would not impact the number of proposed residential units and would, therefore, not have an effect on the ability for project residents to utilize evacuation routes during an emergency. Regardless, the City's Hazard Mitigation Plan command structure would be implemented during emergency responses in order to assess and identify locations and severity of threats to homes, businesses, and other land uses. The City's existing emergency response system, including the manner in which emergency evacuations are initiated and managed, would be sufficient to address emergency evacuation scenarios in the event of future wildfires in the project area that result in a need to evacuate some or all of the proposed 371-home residential community. As such, implementation of the revised project would not adversely affect the emergency response protocols established by the City's Hazard Mitigation Plan or current best practices. Therefore, there are no material changes in circumstances and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. b. As discussed above, the revised project would not change the number of homes built in a wildland fire hazard setting. As with the approved project, development of the site under the revised project would reduce the fuel loads on -site and could, therefore, reduce the volume of smoke and pollutants that could be generated if a wildfire were to occur on -site in the current conditions. In addition, no building permits would be issued by the City until construction plans have been reviewed and determined to be in full compliance with all applicable standards for development in a Very High Fire Hazard Severity Zone. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. W c. Mitigation Measures MM 3.15-1 and MM 3.15-2 would be retained to reduce construction -related accidental ignition impacts to a less -than -significant level. In addition, Mitigation Measure MM 3.15-3 would ensure that an Emergency Vehicle Access Plan is prepared for the duration of construction. In addition, the revised project would be subject to all of the same fuel modification zone requirements imposed by the LACFD. Overall, with implementation of Mitigation Measures MM 3.15-1 through 3.15- 3, impacts under the revised project would be less than significant, and would be similar to those of the approved project. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. d. The revised project would involve minimal grading associated with installation of the proposed fence line and leveling of the space in between the existing and proposed fence lines to create an access road. There would be some vegetation removal in the vicinity of the proposed fence line; however, this vegetation removal would effectively reduce the vegetation fuel load and would reduce chances that a wildfire would denude the area and create possible landslide or flooding conditions due to loose/bare slopes. The revised project would not alter the project's drainage system, which is designed to comply with all applicable standards for collecting, retaining, and discharging runoff during various intensity rainstorms. Therefore, there are no material changes in circumstances, and the revised project would not result in any new significant or substantially more severe environmental impacts that would affect the determination in the Certified EIR. III. Justification for Addendum to Certified Final EIR On the basis of substantial evidence in the light of the whole record, including the analysis above, the revised project and its environmental effects are consistent with the findings of the Certified Final EIR, and there are no conditions that meet the criteria in Section 15162 requiring a Subsequent EIR. The revised project is in substantial conformance with the project identified in the Certified Final EIR. There are no material changes in circumstances under which the revised project would proceed. The revised project does not result in any new significant impacts or an increase the severity of any significant environmental impacts discussed in the Certified Final EIR. The revised project does not require any additional mitigation measures. The previously identified mitigation measures remain valid and adequate to reduce potential impacts to less -than -significant levels. On the basis of the evaluation contained in this document, there are no substantial changes to the approved project, no substantial changes in the circumstances under which the revised project is being undertaken, and no new information of substantial importance that was not known to the Lead Agency at the time the EIR was certified that trigger any of the conditions identified in Public Resources Code Section 21166 or State CEQA Guidelines Section 15162, which would require a subsequent or supplemental EIR. Therefore, pursuant to Sections 15162 and 15164 of the State CEQA Guidelines, this Addendum has been prepared to document the basis for this determination.