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As discussed in the Impact Analysis Memorandum, the Proposed Project would result in a 297.60-acre reduction of impacts to coastal sage scrub vegetation communities, which equates to a 71.5% reduction of impacts when compared to the Approved Project. Many of the coastal sage scrub communities that would be avoided comprise suitable habitat for coastal California gnatcatcher (Glenn Lukos Associates, 2025). The 2024 focused surveys for coastal California gnatcatcher did not identify any new individuals or ter ritories. Focused surveys will be conducted again prior to construction of the Proposed Project to comply with mitigation measure 4.3-5.
In summary, the Proposed Project would result in approximately 123.46 acres of impacts to suitable coastal California gnatcatcher habitat, which is approximately 179.47 acres less of impacts to suitable habitat for coastal California gnatcatcher than was originally authorized by the USFWS in a Biological Opinion (BO) that was issued for the Approved Project in 2017 (Glenn Lukos Associates, 2025).
Given the reduction in impacts to suitable habitat for coastal California gnatcatcher, the Proposed Project would result in reduced impacts when compared to the Approved Project.
As required by the 2011 EIR, the Proposed Project would be required to implement mitigation measure 4.3 -5, which requires that preconstruction surveys be conducted for coastal California gnatcatcher and that USFWS and CDFW be consulted if coastal California gnatcatchers are encountered to determine next steps.
Least Bell’s Vireo
As disclosed in the 2011 EIR. the Project Site contains areas of suitable habitat for least Bell’s vireo, including patches within Tapo Canyon Creek. The 2011 EIR stated that least Bell’s vireo had been observed at other locations in the vicinity of the Pr oject Site, but not within the Project Site itself. The 2011 EIR found that the Approved Project would have significant impacts related to least Bell’s vireo, including the direct removal of habitat, which would be mitigated through conservation of habitat for this species. Protocol-level surveys for least Bell’s vireo and other special status riparian birds were conducted in the Project Site in 2018, 2020, 2022, 2023, and 2024. According to the Project’s Biological Resources Memorandum, there is no suitable habitat present in the impact footprint for the Proposed Project for least Bell’s vireo or other special status riparian bird species. As such, the Proposed Project would have reduced impacts related to least Bell’s vireo when compared to the Approved Project.
As required in the 2011 EIR, the Proposed Project would be required to implement mitigation measure 4.3-3, which requires that within one year prior to the grading or other proposed disturbances to Tapo Canyon Creek, the applicant shall retain a qualified biologist to conduct least Bell’s vireo surveys, in accordance with USFWS protocols in areas of suitable habitat. Also, as required by mitigation measure 4.3-3, if construction activities are going to occur within the nesting season of the least Bell’s vir eo, and if least Bell’s vireo individuals or active nests are observed or detected during protocol surveys, construction activities in the area shall be halted/postponed, and the CDFW and USFWS shall be contacted and informed of the finding immediately. The Proposed Project would also implement mitigation measure 4.3-3 also includes minimum requirements for compensatory mitigation of least 1009
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Bell’s vireo habitat should it be impacted during construction. The Proposed Project would no longer include any impacts to Tapo Canyon Creek. As such, mitigation measure 4.3-3 is no longer applicable to the Proposed Project.
Pursuant to Section 7 of the Endangered Species Act, a Biological Opinion was previously issued for the Approved Project, which allows for one pair and one individual least Bell’s vireo. Given the above, the Approved Project would not result in any increas ed impacts or new mitigation related to least Bell’s vireo.
Southwestern Willow Flycatcher
The 2011 EIR found that the Approved Project would not result in any anticipated impacts to southwestern willow flycatcher given the species has never been observed on the Project Site or in the vicinity. Protocol-level surveys for southwestern willow flycatcher, were conducted in the Project Site in 2018, 2020, 2022, 2023, and 2024. According to the Project’s Biological Resources Memorandum, there is no suitable habitat present in the impact footprint for the Proposed Project for southwestern willow flycatcher. As such, the Proposed Project would have no impacts to southwestern willow flycatcher, which is consistent with the Approved Project.
Western Burrowing Owl
The 2011 EIR disclosed that the Project Site contained suitable habitat for western burrowing owl and that this species had been previously recorded in the Project Site and nearby vicinity. Given the Approved Project’s impacts to suitable habitat for burrowing owl, the 2011 EIR identified that this species would be significantly impacted prior to mitigation.
In 2014, the California Fish and Game Commission published their decision to make western burrowing owl a candidate for listing on the California Endangered Species Act. As such, the western burrowing owl now receives the same legal protection afforded to an endangered or threatened species.
As discussed in the Burrowing Owl Report, three burrowing owl surveys were conducted on January 6 – 7, January 19 – 20, and February 5 - 6, 2026, each spanning a two-day duration.
No burrowing owls have been observed. Additionally, i t is noted that pre -construction surveys conducted in October and November 2024 detected no burrowing owls or diagnostic sign thereof within or adjacent to the Project Site.
As required by mitigation measure 4.3 -5, the Applicant will be required to conduct a preconstruction burrowing owl survey no more than three days prior to start of grading and major earthwork activities and to implement avoidance measures if burrowing owl are determined to be present during such surveys. Should burrowing owls be present, t he protected area (500-foot buffer between Project activities and nesting burrowing owls during nesting season) wi ll remain in effect until August 31 or at CDFW’s discretion and based upon monitoring evidence, unless the young owls are foraging independently. Results of the surveys and relocation efforts shall be provided to CDFW in a mitigation status report.
The 2011 EIR described that the Approved Project would result in impacts to suitable habitat for northern harrier, which has been previously observed in the Project Site. 1010
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The 2011 EIR described that the Approved Project would result in impacts to suitable habitat for yellow warbler, which has been previously observed in the Project Site. With implementation of mitigation measure 4.3 -4, which requires nesting bird surveys be conducted in certain situations and that nesting birds be avoided, impacts related to thi s species would be reduced to less than significant levels.
White-Tailed Kite
The 2011 EIR described that the Approved Project would result in impacts to suitable nesting and foraging habitat for white -tailed kite, which has moderate to high potential to occur on the Project Site. With implementation of mitigation measure 4.3 -4, which requires nesting bird surveys be conducted in certain situations and that nesting birds be avoided, impacts related to this species would be reduced to less than significant levels. The Proposed Project would result in fewer overall impacts to habitat for white-tailed kite than would the Approved Project. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a reduction in impacts of 485.50 acres ( Chambers Group, 2024a). By substantially reducing the acreage of impacts, the Proposed Project would also reduce impacts to white-tailed kite when compared to the Approved Project Western Spadefoot Toad
The 2011 EIR disclosed that the Approved Project would result in impacts to suitable habitat for western spadefoot toad, which had been observed in the Project Site. Therefore, the 2011 EIR included mitigation measure 4.3 -2, which requires that focused sur veys for western spadefoot toad, two -striped garter snake, and western pond turtle be conducted in consultation with CDFW and that if any of these species are identified in the Project Site that sensitive species protection plans be prepared and approved b y CDFW prior to beginning construction. With implementation of this measure, impacts would be reduced to a less than significant level for this species. A habitat assessment was conducted in 2019 and 2023 for western spadefoot toad. The Applicant prepared a Western Spadefoot Toad Protection Plan for the Approved Project, in which a mitigation program would be implemented if the Approved Project were to (1) directly impact a western spadefoot toad occupied seasonal depression or lands within 250 feet of the occupied depression, and/or (2) directly impact lands occupied by western spadefoot toad adults. No western spadefoot toads were found within the impact footprint for the Proposed Project during the 2019 or 2023 surveys. The quality of the habitat within these proposed impact areas of the Project Site were determined not to be suitable for the western spadefoot toad. As discussed in the Proposed Project’s Biological Resources Technical Memorandum, bio -filters proposed to be impacted by the Proposed Project were determined to not contain suitable habitat for western spadefoot toad. Given the above, the Approved Project would not result in any increased impacts or new mitigation related to western spadefoot toad.
Two-Striped Garter Snake
The 2011 EIR disclosed that the Approved Project would result in impacts to suitable habitat for two-striped garter snake, which has potential to occur in the Project Site. Therefore, the 1011
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2011 EIR included mitigation measure 4.3 -2, which requires that focused surveys for western spadefoot toad, two-striped garter snake, and western pond turtle be conducted in consultation with CDFW and that if any of these species are identified in the Project Site that sensitive species protection plans be prepared and approved by CDFW prior to beginning construction. With implementation of this measure, the 2011 EIR Determined that impacts would be reduced to a less than significant level for this species. As discussed in the Proposed Project’s Biological Resources Technical Memorandum, there is no suitable habitat for two - striped garter snake present within the impact footprint for the Proposed Project. Given the above, the Approved Project would not result in any increased impacts or new mitigation related to two-striped garter snake.
Western Pond Turtle
The 2011 EIR disclosed that the Approved Project would result in impacts to suitable habitat for southwestern pond turtle and that this species has potential to occur in the Project Site.
Therefore, the 2011 EIR included mitigation measure 4.3 -2, which req uires that focused surveys for western spadefoot toad, two -striped garter snake, and western pond turtle be conducted in consultation with CDFW and that if any of these species are identified in the Project Site that sensitive species protection plans be prepared and approved by CDFW prior to beginning construction. With implementation of this measure, the 2011 EIR determined that impacts would be reduced to a less than significant level for this species. The Proposed Project’s Biological Resources Technical Memorandum determined that there is no suitable habitat for western pond turtle present within the impact footprint for the Proposed Project.
Given the above, the Approved Project would not result in any increased impacts or new mitigation related to western pond turtle.
Coastal Whiptail
The 2011 EIR disclosed that the Approved Project would result in impacts to suitable habitat for coastal whiptail, which had been observed in the Project Site. Mitigation measure 4.3 -5 was specified requiring preconstruction coastal whiptail surveys, which would reduce impacts related to this species. The Proposed Project would result in fewer overall impacts to habitat for coastal whiptail than would the Approved Project. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a reduction in impacts of 485.50 acres (Chambers Group, 2024a). By substantially reducing the acreage of impacts, the Proposed Project would also reduce impacts to white -tailed kite when compared to the Approved Project
Coast Horned Lizard
The 2011 EIR disclosed that the Approved Project would result in impacts to suitable habitat for coast horned lizard, which had been observed in the Project Site. Mitigation measure
4.3-5 was specified requiring preconstruction coast horned lizard surveys, which would reduce impacts related to this species. The Proposed Project would result in fewer overall impacts to habitat for coast horned lizard than would the Approved Project. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a 1012
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reduction in impacts of 485.50 acres ( Chambers Group, 2024a). By substantially reducing the acreage of impacts, the Proposed Project would also reduce impacts to coast horned lizard when compared to the Approved Project.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, and regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service? No Substantial Change from Previous Analysis. The Proposed Project would result in a
78.4% reduction in impacts to riparian habitat (Glenn Lukos Associates, 2025).
Similarly, the Proposed Project would result in reduced impacts to sensitive natural communities in the Project Site, which include Southern Willow Scrub, Mulefat Scrub, Willow Riparian, Western Sycamore Woodland, and Coast Live Oak Woodland (Glenn Lukos Associates, 2025). For example, the Proposed Project would result in an 86.2% reduction in impacts to Coast Live Oak Woodland areas of the Project Site (Glenn Lukos Associates, 2025).
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
No Substantial Change from Previous Analysis. The 2011 EIR disclosed that the Approved Project would result in impacts to streams and other jurisdictional waters, which would require the issuance of permits from the CDFW, RWQCB, and USACE. The 2011 EIR identified that the Approved Project would result in impacts to approximately 6.37 acres of jurisdictional waters. As required by mitigation measures 4.3-18 through 4.3 -27 from the 2011 EIR, the Applicant would obtain permits from CDFW, RWQCB, and USACE and w ould negotiate compensatory mitigation with the regulatory agencies prior to conducting work in jurisdictional waters.
Based on the revised design for the Proposed Project, impacts to USACE jurisdictional waters have been reduced to 0.52-acre of permanent impacts. As required by the Section 404 permit that was issued b y USACE for the Proposed Project, the Applicant would be required to implement on -site compensatory mitigation totaling 15.44 acres associated with USACE jurisdictional waters in the Project Site, as follows:
• 5.63 acres establishment of southern mixed willow riparian forest, mulefat scrub, coastal sage scrub, coyote brush scrub, and coast live oak woodland; 1013
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• 6.85 acres re-establishment of southern mixed willow riparian forest, mulefat scrub, and coastal sage scrub; and
• 2.96 acres of enhancement/invasive species removal of southern mixed willow riparian forest (1.48 ac credit received at 0.5:1 ratio).
Conservation easements have been recorded over the mitigation sites.
Impacts to CDFW streambed have been reduced to 3.77 acres of impacts. Similar to the mitigation approach for USACE jurisdictional waters, the Proposed Project would mitigate for 3.77 acres of impacts to CDFW streambed by implementing 15.44 acres of mitigation associated with CDFW streambed in the Project Site as follows:
• 5.63 acres establishment of southern mixed willow riparian forest, mulefat scrub, coastal sage scrub, coyote brush scrub, and coast live oak woodland; • 6.85 acres re-establishment of southern mixed willow riparian forest, mulefat scrub, and coastal sage scrub; and
• 2.96 acres of enhancement/invasive species removal of southern mixed willow riparian forest (1.48 ac credit received at 0.5:1 ratio).
Conservation easements have been recorded over the mitigation sites.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
No Substantial Change from Previous Analysis. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a reduction in impacts of 485.50 acres (Chambers Group, 2024a). By substantially reducing the acreage of impacts, entirely within the same overall footprint as the Approved Project, the Proposed Project would also reduce impacts related to wildlife movement when compared to the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
No Substantial Change from Previous Analysis . The 2011 EIR described that there were 683 protected trees inventoried in the Project Site, pursuant to the requirements contained in the City of Simi Valley’s Development Code. The 2011 EIR disclosed that there would be 366 City-protected trees that would need to be directly impacted and/or removed in the Project Site as a result of the Approved Project. The Proposed Project would require the 1014
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removal of ## protected trees, which is a reduction in impacts of ## trees when compared to the 683 protected trees that were assumed to be removed as a part of the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?
No Substantial Change from Previous Analysis. The Proposed Project does not occur within the boundaries of a Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan. As such, the Proposed Project would result in no impact related to this threshold.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to biological resources that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to biological resources continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.4 CULTURAL RESOURCES
3.4.1 2011 EIR
The 2011 EIR identified that there were seven archaeological sites and nine isolated occurrences of prehistoric artifacts within the Project Site. As part of the development of the 2011 EIR, Phase I and Phase II investigations of the seven archaeological sites in the Project Site were conducted, which determined that these sites were not significant and that no additional studies of these sites were warranted. The 2011 EIR found that the Approved Project had a potential to result in the discovery of unknown archaeological resources in the Project Site. Mitigation measures 4.4. -1 through 4.4-5 were required for the Approved Project to mitigate impacts related to archaeological resources to less than significant levels.
The 2011 EIR found that there were no known cemeteries or burial grounds on the Project Site, but that the Project Site has a history of use by Native Americans . Therefore, the 2011 EIR determined that there was potential for the discovery of human remains, including unmarked burial grounds. Because the potential exists for human remains to be unearthed during the Proposed Project’s grading activities, mitigation measure 4.4-6 was required for the Approved Project to mitigate impacts related to human remains.
The 2011 EIR disclosed that Patterson Ranch, which is a designated Ventura County Historical Landmark No. 71, is located in the Project Site adjacent to Bennett Road. As discussed in the 2011 EIR, t here is a current historic resources management plan for the Whiteface Specific Plan that the Approved Project would be required to comply with.
Structures associated with Patterson Ranch would be impacted by the Approved Project; therefore, mitigation measure 4.4 -7 was required for the Approved Project which required that the Approved Project would modify its grading activities to exclude the Patterson Ranch Historical Landmark. Mitigation measure 4.4 -7 required that grading activities shall not occur within 50 feet from the boundary of the Ventura County Historical Landmark No. 71 (Patterson Ranch) boundary.
Mitigation Program
• 4.4-1. Prior to the issuance of a grading permit, the project applicant shall retain a City-approved archaeologist to develop an archaeological mitigation and monitoring plan and a discovery clause/treatment plan. Both plans shall be reviewed and approved by the City Planning Division. The discovery clause/treatment plan shall include recovery and subsequent treatment of any archaeological or historical remains and associated data uncovered by brushing, grubbing, or excavation. The treatment plan shall prov ide procedures for the curation of any detected cultural specimens. Any recovered cultural resources shall be identified, sites recorded, mapped, and artifacts catalogued as required by standard professional archaeological practices. Examination by an archaeological spe cialist shall be included where necessary, dependent upon the artifacts, features, or sites that are encountered.
Specialists will identify, date, and/or determine significance potential. A copy of the 1016
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executed agreement for monitoring the rough grading by the archaeologist and a Chumash monitor shall be submitted prior to issuance of the grading permit. • 4.4-2. Prior to grading operations, a City-approved archaeologist shall be retained to make an assessment of the grading area to determine if full -time monitoring is needed. If the City -approved archaeologist is not needed full -time during grading activities, they shall be retained on -call during grading operations. If during earthmoving activities archaeological cultural deposits are discovered, all earthmoving activities shall be diverted temporarily in the immediate area (not less than 50 feet from the discovery site) around the deposits until the deposits have been evaluated, recorded, excavated, and/or recovered by a City -approved archaeologist, as necessary, and in accordance with the City -approved recovery plan. Earthmoving shall be allowed to proceed through the area after the archaeologist determines the artifacts are recovered and/or site mitigated to the extent necessary. • 4.4-3. If a previously unknown cultural site is encountered during monitoring and it is determined by the archaeologist that a significance determination is required, the site shall be evaluated and recorded in accordance with requirements of the State Office of Historic Preservation (i.e., DPR 523 form). In this case, if the site is not determined to be significant, no measure subsequent to recording the site on appropriate forms is required. If any of the sites are determined to be significant, the City-approved archaeologist shall collect an adequate amount of artifacts at the specific archaeological site. The archaeologist shall determine the amount of artifacts needed to be collected.
• 4.4-4. Any recovered archaeological resources should be identified, sites recorded, mapped, and artifacts catalogued as required by standard archaeological practices.
Examination by an archaeological specialist should be included where necessary, dependent upon the artifacts, features, or sites that are encountered. Specialists will identify, date, and/or determine significance potential. • 4.4-5. A final report of findings will be prepared by the City -approved archaeologist for submission to the City, project applicant, and the South Central Coastal Information Center at California State University, Fullerton. The report will describe the history of the project area, summarize field and laboratory methods used, if applicable, and include any testing or special analysis information conducted to support the resultant findings.
• 4.4-6. If human remains are encountered during excavations associated with this project, all work shall halt, and the Ventura County Coroner shall be notified (Section 5097.98 of the Public Resources Code). The coroner will determine whether the remains are of f orensic interest. If the coroner, with the aid of the City -approved archaeologist, determines that the remains are prehistoric, he/she will contact the Native American Heritage Commission (NAHC). The NAHC will be responsible for designating the most likely descendant (MLD), who will be responsible for the ultimate disposition of the remains, as required by Section 7050.5 of the California Health and Safety Code. The MLD will make his/her recommendations within 24 hours of being notified by the NAHC. T his recommendation may include scientific 1017
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removal and nondestructive analysis of human remains and items associated with Native American burials (Section 7050.5 of the Health and Safety Code). • 4.4-7. Prior to approval of Tentative Tract Maps, the project grading disturbance line shall be modified to exclude the Patterson Ranch Historical Landmark. Grading activities shall not occur within 50 feet from the boundary of the Ventura County Historical Landmark No. 71 (Patterson Ranch) boundary.
• 4.4-8. Prior to the issuance of grading permits, the project applicant shall retain a City- approved paleontologist to prepare a paleontological mitigation plan for the project.
The mitigation plan shall include recovery and subsequent treatment of any paleontological resources and associated data uncovered by brushing, grubbing, or excavation. The treatment plan shall provide procedures for the curation of any detected paleontological resources. Any recovered paleontological resources shall be identified, sites recorded, mapped , and catalogued as required by standard professional paleontological practices. Examination by a qualified paleontologist shall be included where necessary, dependent upon the artifacts, features, or sites that are encountered. A qualified paleontologist will identify, date, and/or determine significance potential.
• 4.4-9. If during earthmoving activities paleontological deposits are discovered, all earthmoving activities shall be diverted temporarily in the immediate area (not less than 100 feet from the discovery site) around the deposits until the deposits have been evaluated, recorded, excavated, and/or recovered by a qualified paleontologist.
Earthmoving shall be allowed to proceed through the area after the paleontologist determines the artifacts are recovered and/or site mitigated to the extent necessary.
The qualified paleontologist will prepare a final monitoring and mitigation report to be filed with the client, the lead agency, and the repository. • 4.4-10. Should the paleontological resource be determined to be significant by the paleontologist, the fossil discovery locality and field data forms will be used to record pertinent geologic data, stratigraphic sections will be measured, and appropriate sediment samples will be collected and submitted for analysis. Matrix sampling will be conducted to test for the presence of microfossils. Testing for microfossils shall consist of screen-washing small samples (approximately 200 pounds) to determine if significant fossils are present. If microfossils are present, additional matrix samples will be collected (up to 6,000 pounds per locality to ensure recovery of a scientifically significant microfossil sample).
• 4.4-11. Recovered fossils will be prepared to the point of curation, identified by a qualified paleontologist, listed in a database to facilitate analysis, and reposited in a designated paleontological curation facility, such as the Los Angeles County Museum. 1018
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3.4.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
CULTURAL RESOURCES – Would the project:
a) Cause a substantial adverse change in the significance of a historical resource pursuant to Section 15064.5?
b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5?
c) Disturb any human remains, including those interred outside of formal cemeteries?
The responses in this section are partially based on a Cultural and Paleontological Resources Technical Memorandum that was prepared for the Proposed Project by Chambers Group in September 2024 (Chabers Group 2024c).
Would the Project:
a) Cause a substantial adverse change in the significance of a historical resource pursuant to Section 15064.5? and
b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5? and
c) Disturb any human remains, including those interred outside of formal cemeteries? No Substantial Change from Previous Analysis. The updated record search and archival research results that were conducted for the Proposed Project did not substantively change the overall context, or the documented cultural sensitivity that was previously addressed in the 2011 EIR.
The Proposed Project would result in fewer overall impacts when compared to the Approved Project. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a reduction in impacts of 485.50 acres ( Chambers Group, 2024a). By substantially reducing the acreage of impacts, the Proposed Project would also reduce the potential for impacts to occur related to historical and archaeological resources, as well as related to human remains.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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Conclusion
The Proposed Project would not result in any new or substantially increased effects related to cultural resources that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to cultural resources continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.5 ENERGY
3.5.1 2011 EIR
Although the topic of energy was not part of the Appendix G of the State CEQA Guidelines at the time that the 2011 EIR was prepared, the topic of energy usage was evaluated in the 2011 EIR as a part of the air quality analyses contained in Section 4.2 of the 2011 EIR , which disclosed that the Approved project would result in demand for electricity, natural gas, gasoline, and other energy sources during construction and operation Mitigation Program
The 2011 EIR did not include mitigation measures directly related to energy.
3.5.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
ENERGY – Would the project:
a) Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation?
b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
The responses in this section are based on an Energy Technical Memorandum that was prepared for the Proposed Project by Michael Baker International in January 2025 (Michael Baker International 2025b).
Would the Project:
a) Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation?
No Substantial Change from Previous Analysis. The 2011 EIR did not evaluate impacts pertaining to energy as it was not required at the time the 2011 EIR was prepared.
The impact analysis contained in the Energy Technical Memorandum prepared for the Proposed Project focuses on the three sources of energy that are relevant to the Proposed Project: electricity, natural gas, and transportation fuel for vehicle trips associated with project operations as well as the fuel necessary for project construction. The California Emissions Estimator Model (CalEEMod) version 2022.1 was utilized in the development of 1021
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the Energy Technical Memorandum to calculate the Proposed P roject’s construction and operational energy consumption.
As shown in Energy Technical Memorandum, during operation, the Proposed Project would constitute an approximate 0.0415 percent increase over County’s typical annual electricity consumption and an approximate 0.0924 percent increase over the County’s typica l annual natural gas consumption; and vehicle fuel consumption would increase Ventura County’s consumption by 0.2579 percent. During Phase 1 of construction of the Proposed Project, off- road construction equipment diesel fuel consumption and on -road constr uction fuel consumption would increase Ventura County’s consumption by 2.1068 percent and 0.0153 percent, respectively. During construction of the Proposed Project, off-road construction equipment diesel fuel consumption and on -road construction fuel consumption would increase Ventura County’s consumption by 2.4614 percent and 0.0340 percent, respectively.
Construction Energy Consumption
The Energy Technical Memorandum found that the Proposed Project would result in energy consumption in two general forms: (1) the fuel energy consumed by construction vehicles and equipment; and (2) bound energy in construction materials, such as asphalt, steel, concrete, pipes, and manufactured or processed materials such as lumber and glass. Fossil fuels for construction vehicles and other energy -consuming equipment would be used during demolition, grading, building construction, paving, and architectural coating. During construction of the Proposed Project, off-road fuel consumption and on -road fuel consumption would be approximately 111,911 gallons and 93,147 gallons, respectively.
Consequently, the Proposed Project’s off -road construction equipment diesel fuel consumption and on -road construction fuel consumption during Phase 2 would increase Ventura County’s consumption by 2.4614 percent and 0.0340 percent, respectively. As such, the Proposed Project’s construction would have a minimal effect on the loca l and regional energy supplies and would not require additional capacity. Some incidental energy conservation would occur during construction through compliance with State requirements that equipment not be in use for more than five minutes be turned off (i.e., Title 13, California Code of Regulations Section 2485). The Proposed Project’s construction equipment would also be required to comply with the latest U.S. Environmental Protection Agency (USEPA) and CARB engine emissions standards. These emissions s tandards require highly efficient combustion systems that maximize fuel efficiency and reduce unnecessary fuel consumption.
In addition, because the cost of fuel and transportation is a significant aspect of construction budgets, contractors and owners have a strong financial incentive to avoid wasteful, inefficient, and unnecessary consumption of energy during construction.
Substantial reductions in energy inputs for construction materials can be achieved by selecting building materials composed of recycled materials that require substantially less energy to produce than nonrecycled materials. The integration of green buildin g materials can help reduce environmental impacts associated with the extraction, transport, processing, fabrication, installation, reuse, recycling, and disposal of these building industry source material. The Proposed Project’s incremental increase in the use of energy bound in construction materials such as asphalt, steel, concrete, pipes and manufactured or processed materials (e.g., lumber and gas) would not substantially increase demand for energy 1022
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compared to overall local and regional demand for construction materials. Further, it is noted that construction fuel use is temporary and would cease upon completion of construction activities. There are no unusual project characteristics that would neces sitate the use of construction equipment, or building materials, or methods that would be less energy efficient than at comparable construction sites in the region or State. Therefore, the Energy Technical Memorandum determined that the Proposed Project’s fuel energy and construction materials consumed during construction would not represent a significant demand on energy resources and a less than significant impact would occur in this regard.
Operational Energy Consumption
Transportation Energy Demand
Pursuant to the Federal Energy Policy and Conservation Act of 1975, the National Highway Traffic and Safety Administration is responsible for establishing additional vehicle standards and for revising existing standards. Compliance with federal fuel econom y standards is not determined for each individual vehicle model. Rather, compliance is determined based on each manufacturer’s average fuel economy for the portion of their vehicles produced for sale in the United States. As indicated in the Energy Technic al Memorandum prepared for the Proposed Project, operational fuel consumption for the Proposed Project is estimated to be approximately 658,862 gallons per year, which would increase Countywide automotive fuel consumption by 0.2579 percent. The Proposed Project does not propose any unusual features that would result in excessive long -term operational fuel consumption. The key drivers of transportation -related fuel consumption for the Proposed Project are passenger vehicles traveling to and from the Project Site. Additionally, light- and medium-duty trucks trips also account for a portion of the transportation -related fuel consumption used for street cleaning and trash collection that would be required for the Proposed Project . To reduce these potential impacts , the Proposed Project would provide electric vehicle (EV) charging facility in compliance with the Title 24 standards and would include short - and long-term bicycle parking spaces. This requirement would encourage and support alternative modes of travel and would thus reduce fuel consumption. Therefore, fuel consumption associated with vehicle trips generated by the project would not be considered inefficient, wasteful, or unnecessary in comparison to other similar develo pments in the region. The Energy Technical Memorandum determined that the Proposed Project would result in a less than significant impact related to transportation energy demand and no mitigation is required.
Building Energy Demand
The CEC developed 2024 to 2040 forecasts for energy consumption and peak demand in support of the 2023 IEPR for each of the major electricity and natural gas planning areas and the State based on the economic and demographic growth projections. CEC forecas ted baseline electricity consumption grows at a rate of about 1.7 percent annually through 2040 according to the Energy Technical Memorandum . The natural gas consumption grows at a rate of about 0.2 percent annually through 2035.1 As shown in the Energy Te chnical Memorandum for the Proposed Project, operational energy (electricity and natural gas) consumption for the Proposed Project wo uld represent approximately 0.0415 and 0.0924 1023
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percent increase over the current Countywide electricity and natural gas consumption, which would be significantly below CEC’s forecasts. Therefore, the Proposed Project would be consistent with the CEC’s energy consumption forecasts and would not require additional energy capacity or supplies. Additionally, the Proposed Project would consume energy during the same time periods as other surrounding developments and would consume energy evenly throughout the day. As a result, the Proposed Project would not r esult in unique or more intensive peak or base period electricity demand. The Proposed Project would be required to comply with the most current Title 24, which provide minimum efficiency standards related to various building features, including appliances, water and space heating and cooling equipment, building insulation and roofing, and lighting.
Implementation of the most current Title 24 standards significantly reduces energy usage.
Title 24 Building Energy Efficiency Standards are updated every 3 -year and become more stringent between each update, as such complying with the most current Title 24 standards would make the Proposed Project more energy efficient than existing buildings built under the earlier versions of the Title 24 standards. Additionally, while the project would not install renewable energy systems for on -site energy generation, the installation solar -ready roofs would allow for the future addition of on-site energy production. The electricity provider for the City, SCE, is subject to California’s Renewables Portfolio Standard (RPS) reflected in SB 100. The RPS requires investor -owned utilities, electric service prov iders, and community choice aggregators to increase procurement from eligible renewable energy resources to 44 percent by the end of 2024, 52 percent by the end of 2027, 60 percent of total procurement by 2030, and 100 percent of total procurement by 2045. Renewable energy is generally defined as energy that comes from resources which are naturally replenished within a human timescale such as sunlight, wind, tides, waves, and geothermal heat. The increase in reliance of such energy resources further ensures that new development projects will not result in the waste of the finite energy resources. In summary, the Energy Technical Memorandum determined that the Proposed Project would result in a less than significant impact related to building energy demand and no mitigation is required.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
No Substantial Change from Previous Analysis. The City does not have a plan adopted specifically for renewable energy or energy efficiency. As such, the analyses contained in the Proposed Project’s Energy Technical Memorandum focused on the Proposed Project’s consistency with applicable objectives, policies, and measures within the City’s General Plan as well as the City’s CAP.
The Energy Technical Memorandum determined that the Proposed Project would comply with all applicable goals and policies identified in the City’s General Plan and CAP. The Energy Technical Memorandum determined that operational energy consumption for the Proposed Project would be substantially below CEC’s forecasts in the 2023 IEPR (i.e., 1024
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Statewide annual average growth rates of energy demand would be 1.7 percent for electricity and 0.2 percent for natural gas). Therefore, the Proposed Project was determined to be consistent with the CEC’s 2023 IEPR. Further, the Proposed Project was determined in the Energy Technical Memorandum would be required to comply with the most current Title 24 (2022 Title 24), which provide minimum efficiency standards related to various building features, including appliances, water and space heating and cooling e quipment, building insulation and roofing, and lighting. The Proposed Project would also comply with the CALGreen standards which requires that new buildings increase building system efficiencies (e.g., lighting, HVAC, and plumbing fixtures) and would incorporate electric vehicles charging infrastructure. Implementation of the most current Title 24 standards would significantly reduce energy usage for the Proposed Project . Additionally, per the RPS, the Proposed Project would utilize electricity that would achieve 60 percent of total procurement by 2030, and 100 percent renewable energy by 2045. As such, the Proposed Project would comply with State energy plans including the 2023 IEPR, the most current Title 24 as well as CalGreen standards.
As shown in the Energy Technical Memorandum , the Proposed Project would comply with all applicable City’s goals and policies for reducing energy usage and implementing energy efficiency. Therefore, the Proposed Project would not conflict with or obstruct a State or local plan for renewable energy or energy efficiency and impacts would be less than significant.
To further reduce impacts, the Proposed Project would implement mitigation measure 4.2- 5 from the 2011 EIR, which requires incorporation of measures outlined in the BuildItGreen GreenPoint Checklist to an extent sufficient to score an overall Green Building rating for new residential structures proposed in this project. In conclusion, energy impacts resulting from the Proposed Project would be less than significant. The Proposed Project would not result in any new significant impacts compared to impacts that were disclosed in the 2011 EIR.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to energy that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to energy continue to apply; however, no new mitigation measures a re proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.6 GEOLOGY AND SOILS
3.6.1 2011 EIR
The 2011 EIR analyzed potential impacts associated with the geological and soils conditions on the Project Site. Geotechnical evaluations of the Project Site were prepared as a part of the development of the 2011 EIR , which determined that the geotechnical characteristics vary greatly across the Project Site.
The 2011 EIR found that seismic activity is common across California, and that the Approved Project would result in less than significant impacts related to rupture of a known earthquake faul t and strong seismic ground shaking with implementation of mitigation measures 4.5-1 and 4.5 -2. Site investigations conducted for the 2011 EIR determined that the Simi-Santa Rosa fault is outside the limits of proposed development for the Proposed Project and there are no other known faults in the Project Site. Related to the proposed water tank, the 2011 EIR determined that the site where the water tank was proposed was neither underlain, nor immediately adjacent to active faults as defined by the State of California. The 2011 EIR disclosed that the nearest known active fault to the proposed water tank would be the SSRF, which is also a Alquist-Priolo Zone, located 1.5 miles south of the project boundary.
Mitigation measure 4.5 -1 requires that prior to the approval of tract maps an earthquake engineering evaluation shall be performed to determine if ground motions within the Project Site would be amplified to an extent where greater than CBC and City code design values are required. A report documenting this evaluation shall be submitted to the City that contains appropriate design recommendations . Mitigation measure 4.5-2 requires that p rior to approval of tentative tract maps, a detailed geotechnical investigation shall be performed by a state-certified geologist for the proposed water tank development and submitted to the City Engineer for review and approval. The investigation shall provide sufficient subsurface exploration to adequately characterize the site conditions. The investigation sh all also address the various geotechnical aspects, including assessments for secondary earthquake effects of the proposed water tank development.
The 2011 EIR found that the Approved Project would result in significant impacts related to seismic-related ground failure, including liquefaction, which would put buildings built in the Project Site at higher risk of damage than buildings built on sites that are not susceptible to liquefaction. The 2011 EIR included mitigation measures 4.5 -3 and 4.5-4 to reduce impacts related to this threshold to a less than significant level.
Mitigation measure 4.5-3 requires that pr ior to the approval of grading permits, a report documenting an evaluation of liquefaction zones shall be prepared for the Approved Project that shall contain appropriate liquefaction design recommendations for the proposed residential development. As required by mitigation measure 4.5 -3, the known liquefaction zones in the impact footprint for the Approved Project shall be evaluated prior to the approval of grading permits to determine if groundwater is present and if soil/alluvial conditions are conducive to liquefaction and lateral spreading considering the potential earthquake ground shaking conditions for the site. Mitigation measure 4.5-3 requires that a report documenting this evaluation be prepared and submitted to the City Engineer for 1026
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review and approval and that t he analysis contain appropriate liquefaction design recommendations (if needed) for the proposed residential development.
Mitigation measure 4.5-4 requires that p rior to issuance of final grading permits, areas within the impact footprint of the Approved Project that have been determined by the State to have liquefaction and/or dynamic settlement potential, shall be appropriately remediated.
Remediation may include the removal and replacement of liquefiable soils with compacted, drained fills, ground modification, and the design for potential settlement of liquefiable materials by a licensed civil engineer.
With implementation of mitigation measures 4.5 -3 and 4.5 -4, impacts related to ground failure would be reduced to less than significant levels.
The 2011 EIR disclosed that the Project Site contains a mix of steep topography and loos e soils that are prone to landslides. The 2011 EIR found that f ollowing construction and occupancy of the buildings proposed by the Approved Project , structures and occupants of the Approved Project would be at a higher risk for damage and injury, respectively, if small or large landslides were to be triggered either by earthquakes or by other factors such a heavy rainfall or underground water sources.
The 2011 EIR found that the Approved Project would result in potentially significant impacts related to landslides requiring mitigation. Mitigation measure 4.5-5 was included for the Approved Project requiring that prior to the issuance of grading permits, the soils that have failed or are known to fail in the Project Site, and the resultant voids, shall be replaced with compacted fill and/or construction of buttress fills. All materials to be removed from the Project Site shall be overseen by a City-qualified engineer, free of deleterious materials (such as alluvium, colluvium, and uncompacted artificial fill), properly moisture conditioned, and certified by the City-qualified Engineer to be reused as compacted fill. 4.5-6 Prior to issuance of grading permits, proposed development near overlying natural slopes, boulder roll, and debris flow shall be reviewed and assessed by a City -qualified engineer. Development shall be proposed on the already disturbed areas and shall follow the requirements set forth in the Simi Valley Development Code Hillside Performance Standards. Where mass wasting could impact proposed improvements, procedures to enhance stability or eliminate potential impacts will be necessary on a site specific basis. 4.5 -7 Prior to the issuance of grading permits, areas identified by the state as historical and/or potential landslide zones shall be reviewed by a licensed engineer or geologist and approved by the City Engineer to identify potential debris flow. Measures to stabilize landslides shall be submitted to the City Engineer for review and approval; such measures may include the design and construction of debris basins, containment walls, or debris fencing.
The 2011 EIR found that the Approved Project would result in temporary and permanent impacts related to soil erosion. Temporary erosion impacts would result from clearing, grubbing, and grading that would occur in the Project Site. As discussed in the 2011 EIR, the Approved Project would be required to comply with applicable laws requiring the development and implementation of a Storm Water Pollution Prevention Plan (SWPPP), which would minimize short -term erosion impacts. During operation of the Approved Project, the 2011 EIR disclosed that the Approved Project would result in increased 1027
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impervious surface coverage in the Project Site, which would have the potential to increase erosion when compared to no project conditions. The 2011 EIR found that development of the proposed water tank would result in a potentially significant impact related to erosion.
To reduce potential impacts related to erosion that could result from the proposed water tank, the 2011 EIR found that the Approved Project’s potentially significant impacts would be reduced through implementation of mitigation measure 4.5-8, which requires that p rior to the issuance of grading permits for the water tank pad, the Applicant shall prepare and submit to the City Engineer for review and approval, an analysis of the volume of oversize rock and rock rippability that has been prepared for the Approved Project by a qualified geologist. With implementation of mitigation measure 4.5-8, impacts related to soil erosion would be reduced to less than significant levels.
The 2011 EIR found that the Approved Project would result in potentially significant impacts related to soil instability, including lateral spreading, subsidence, liquefaction, and collapse prior to the implementation of mitigation. The Project Site contains a variety of soil types, some of which are prone to landslides, lateral spreading, subsidence, liquefaction, and collapse. Mitigation measures 4.5-9 through 4.5-19 were specified for the Approved Project in the 2011 EIR to reduce impacts related to this topic to less than significant levels.
As required by mitigation measure 4.5-9, prior to issuance of grading permits, mitigation plans for unstable slopes shall be prepared and submitted to the City Engineer for review and approval. Per mitigation measure 4.5 -9, m itigation may include overexcavation and replacement with either drained stabilization fills or buttress fills. Stabilization fills should be utilized when cut slopes expose loose soils or faulted and fractured bedrock.
As required by mitigation measure 4 .5-10, prior to the issuance or grading permits, a plan for structural setbacks, removal and replacement, or fill buttressing of landslides shall be prepared and submitted to the City Engineer for review and approval. As required by mitigation measure 4.5-10, the support of adverse bedding can be achieved by construction of drained buttress fills, the elimination of adverse bedding by slope layback, or containment of the hazard by catchment devices.
The 2011 EIR required that the Approved Project implement mitigation measure 4.5-11, which requires that p rior to the issuance of grading permits; a plan for the removal of low density surficial soils from fill areas shall be prepared and submitted to the City Engineer for review and approval.
The 2011 EIR required that the Approved Project implement mitigation measure 4.5-12, which requires that prior to the issuance of grading permits plans for manufactured slopes shall be submitted to the City Engineer for review approval. Generally, fill slopes must be designed at a 2:1 (horizontal to vertical) or flatter ratio.
As required by mitigation measure, 4.5-13, prior to the issuance of grading permits for the Proposed Project, where landslides, adverse bedding, faulted or fractured bedrock, or other similar conditions exist on natural slopes superjacent to the planned tank pad and access road, plans for the potential hazard shall be prepared and submitted to the City Engineer for review and approval. As specified in mitigation measure 4.5-13, based on the grading design, 1028
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natural slope gradients, and underlying geologic conditions, mitigation techniques will likely be limited to removal and replacement of landslide debris.
As required by mitigation measure, 4.5-14, p rior to issuance of grading permits, an evaluation of the interrelationships of the various combinations of slope configuration, geologic structure, and material strength characteristics will be prepared and submitted to the City Engineer for review and approval to assess each specific slope condition. Replacing withdrawn fluids with other fluids could mitigate potential for subsidence.
As required by mitigation measure, 4.5-15, prior to issuance of grading permits, site-specific geotechnical investigations to assess the potential for liquefaction under strong earthquake conditions, under the terms of the State of California Seismic Hazard Mapping Act, on all development within the state-designated liquefaction hazard zones shall be performed and the results, along with any proposed design features, submitted to the City Engineer for review and approval.
As required by mitigation measure, 4.5-16, p rior to the issuance of grading permits, a qualified geologist shall develop site -specific analysis of the soils that contain landslide material, adverse bedding, faulted or fractured bedrock, or other similar conditions that exist on natural slopes in pro ximity to planned development, which shall be reviewed and approved by the City Engineer.
The 2011 EIR determined that the p otential risks to life and property related to expansive units for the Approved Project would be potentially significant prior to the implementation of mitigation. Mitigation measure 4.5 -17 was required for the Approved Project, which requires that pr ior to issuance of grading permits, plans for the areas of shallow groundwater and in cut areas, shall be submitted to the City Engineer for review and approval and shall include the installation of subdrains, backdrains, and slope toe drains.
As required by mitigation measure 4.5-18, prior to the issuance of grading permits, plans for those areas in the Project Site that have been designated to have highly expansive soils shall be submitted to the City Engineer for review and approval. Measures to control expansive soils shall include overexcavation of the expansive soils/bedrock and replacement with less expansive fill soils; proper design of foundations, slabs, streets and other improvements subject to the influence of these soils; selective g rading techniques to place more highly expansive soils well below foundation elements; employment of pre -saturation techniques to lessen expansion potential; and control of surface and subsurface drainages to prevent moisture variations.
As required by mitigation measure 4.5-19, at the completion of grading, specific testing for expansion potential shall be performed by a qualified geologist on the as -graded near - surface materials and shall identify the findings in a report which would be submitted to the City Engineer for review and approval
In summary, with implementation of mitigation measure 4.5-9 through mitigation measure
4.5-19 from the 2011 EIR, potentially significant impacts related to soil instability, including potential landslides, lateral spreading, subsidence, liquefaction, and collapse would be reduced to less than significant levels.
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In summary, t he 2011 found that the Approved Project’s i mpacts related to geological hazards would be less than significant with the implementation of the City of Simi Valley ordinances, such as the Hillside Performance Standards (HPS) , the measures contained in the California Building Code (CBC), and mitigation measure 4.5-1 through mitigation measure4.5-19.
As described above, the 2011 EIR includes analysis of the Approved Project’s proposed water tank that would be located just north of the existing water tank within the Project Site . A geotechnical investigation was conducted in the general vicinity of the proposed tank site as a part of the development of the 2011 EIR, which included the excavation and logging of numerous test pits and borings. In addition to the geotechnical investigations, geologic data was obtained during the grading of the existing wate r tank pad. The 2011 EIR determined that i mpacts related to the proposed water tank would be less than significant with implementation of the CBC and proposed mitigation measure 4.5-1 through mitigation measure 4.5-19.
Mitigation Program
• 4.5-1. In addition to all structures being designed in accordance with the California Building Code (CBC) and applicable City codes to ensure safety in the event of an earthquake, prior to the approval of tract maps an earthquake engineering evaluation shall be performed using PGA -based assessments to determine if ground motions within the Project Site would be amplified to an extent where greater than CBC and City code design values are required. A report documenting this evaluation shall contain appropriate design recommendations and shall be prepared and submitted to the City Engineer for review and approval prior to issuance of a grading permit.
This shall include the potential for seiche - or ground failure -induced flooding from the water tank located within the Project Site.
• 4.5-2. Prior to approval of tentative tract maps, a detailed geotechnical investigation should be performed by a state -certified geologist for the proposed water tank development and submitted to the City Engineer for review and approval. The investigation should provide sufficient subsurface exploration to adequately characterize the site conditions. The investigation should address the various geotechnical aspects, including PGA -based assessments for secondary earthquake effects, of the proposed water tan k development and should provide recommendations and mitigation measures as necessary.
• 4.5-3. Prior to the approval of grading permits, a report documenting an evaluation of liquefaction zones shall be prepared and contain appropriate liquefaction design recommendations for the proposed residential development. Identified liquefaction zones (Figure 4.5-5) of the proposed residential development shall be evaluated prior to the approval of grading permits to determine if groundwater is present and if soil/alluvial conditions are conducive to liquefaction and lateral spreading considering the potential earthquake ground shaking conditions for the site. A report documenting this evaluation shall be prepared and submitted to the City Engineer for review and approval. The analysis shall contain appropriate liquefaction design recommendations (if needed) for the proposed residential development. 1030
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• 4.5-4. Prior to issuance of final grading permits, areas within the proposed development determined by the State to have liquefaction and/or dynamic settlement potential, shall include the removal and replacement of liquefiable soils with compacted, drained fill s, ground modification, and design for potential settlement of liquefiable materials by a licensed civil engineer would be required during the design and construction process to adhere to state policy regarding liquefaction.7 Proof of review shall be submitted to the City Engineer. • 4.5-5. Prior to the issuance of grading permits, the soils that have failed or are known to fail, and the resultant voids, shall be replaced with compacted fill and/or construction of buttress fills. All materials to be removed from the Project Site shall be overseen by a City -qualified engineer, free of deleterious materials (such as alluvium, colluvium, and uncompacted artificial fill), properly moisture conditioned, and certified by the City-qualified Engineer to be reused as compacted fill. • 4.5-6. Prior to issuance of grading permits, proposed development near overlying natural slopes, boulder roll, and debris flow shall be reviewed and assessed by a City- qualified engineer. Development shall be proposed on the already disturbed areas and shall fol low the requirements set forth in the Simi Valley Development Code Hillside Performance Standards. Where mass wasting could impact proposed improvements, procedures to enhance stability or eliminate potential impacts will be necessary on a site specific basis.
• 4.5-7. Prior to the issuance of grading permits, areas identified by the state as historical and/or potential landslide zones shall be reviewed by a licensed engineer or geologist and approved by the City Engineer to identify potential debris flow.
Measures to s tabilize landslides shall be submitted to the City Engineer for review and approval; such measures may include the design and construction of debris basins, containment walls, or debris fencing.
• 4.5-8. Prior to the issuance of grading permits for the water tank pad, the developer shall prepare and submit to the City Engineer for review and approval, an analysis of the volume of oversize rock and rock rippability by a qualified geologist. Bedrock units are likely to produce oversize (>12 inches) material during excavation; these oversized materials will require special handling during grading to ensure that oversize materials are not placed at or near pad grades. Typically, deep fills can be used to accommodate oversize rocks, and placement of oversize rock using controlled disposal procedures is an accepted and effective technique. • 4.5-9. Prior to issuance of grading permits, mitigation plans for unstable slopes shall be prepared and submitted to the City Engineer for review and approval. Mitigation may include overexcavation and replacement with either drained stabilization fills or buttress fills. Stabilization fills should be utilized when cut slopes expose loose soils or faulted and fractured bedrock. Where grading limits are not constrained, cut slope instability can be mitigated by constructing slopes at flatter angles than the underlying geologic structure.
• 4.5-10. Prior to the issuance or grading permits, a plan for structural setbacks, removal and replacement, or fill buttressing of landslides shall be prepared and submitted to the City Engineer for review and approval. The support of adverse 1031
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bedding can be achieved by construction of drained buttress fills, the elimination of adverse bedding by slope layback, or containment of the hazard by catchment devices. Correction of local surficial instabilities including debris flow and rockfall will be required and could include establishment of structural setbacks, construction of catchment devices, or physical elimination of the hazard by removal or containment.
• 4.5-11. Prior to the issuance of grading permits; a plan for the removal of low density surficial soils (such as alluvium, colluvium, and landslide materials) from fill areas shall be prepared and submitted to the City Engineer for review and approval. Thi s will, include the identified low -density surficial soils, such as alluvium, colluvium, nonengineered fill and unsuitable landslide materials, prior to fill placement and where exposed at grade in cut areas. As the project design becomes more specific, further evaluation of the limits, depths, and engineering characteristics of low - density, unsuitable soils should be conducted, as required by the City Engineer, by a City-qualified engineer and specific removal criteria should be established. Generally, removed materials may be reused as compacted fill when free of deleterious materials and properly moisture conditioned.
• 4.5-12. Prior to the issuance of grading permits plans for manufactured slopes shall be submitted to the City Engineer for review approval. Fill slopes should be designed at a 2:1 (horizontal to vertical) or flatter ratio. Locally steeper fill slopes can be considered but should be constructed with geosynthetics to enhance the shear strength of fill materials. Higher compaction standards (typically 93 percent of the laboratory maximum density) should be implemented in deeper fills (greater than 50 feet) to enhance engineering characteristics and reduce the amount of potential settlement. Subsurface drainage devices should be installed below fills to intercept and direct water that may seep from the bedrock or be introduced from the surface. • 4.5-13. Prior to the issuance of grading permits, where landslides, adverse bedding, faulted or fractured bedrock, or other similar conditions exist on natural slopes superjacent to the planned tank pad and access road, plans for the potential hazard shall be prepared and submitted to the City Engineer for review and approval. Based on the grading design, natural slope gradients, and underlying geologic conditions, mitigation techniques will likely be limited to removal and replacement of landslide debris. Correction of local surficial instabilities including soil slip/creep may be required and could include establishment of structural setbacks, construction of catchment devices, or physical elimination of the hazard by removal or containment. • 4.5-14. Prior to issuance of grading permits, an evaluation of the interrelationships of the various combinations of slope configuration, geologic structure, and material strength characteristics will be prepared and submitted to the City Engineer for review and approval to assess each specific slope condition. Replacing withdrawn fluids with other fluids could mitigate potential for subsidence. • 4.5-15. Prior to issuance of grading permits, site -specific geotechnical investigations to assess the potential for liquefaction under strong earthquake conditions, under the terms of the State of California Seismic Hazard Mapping Act, on all development within the state -designated liquefaction hazard zones shall be performed and the 1032
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results, along with any proposed design features, submitted to the City Engineer for review and approval.
• 4.5-16. Prior to the issuance of grading permits, a qualified geologist shall develop site-specific analysis of the soils that contain landslide material, adverse bedding, faulted or fractured bedrock, or other similar conditions that exist on natural slop es in proximity to planned development, which shall be reviewed and approved by the City Engineer.
• 4.5-17. Prior to issuance of grading permits, plans for the areas of shallow groundwater and in cut areas, shall be submitted to the City Engineer for review and approval and shall include the installation of subdrains, backdrains, and slope toe drains. In canyon bottoms, beneath design fills, subdrains are typically placed after the removal of unsuitable soils. All such drains should be designed to outlet into approved drainage devices. Control of surface waters is typically accomplished by storm water fac ilities and proper design and maintenance of surface drainage patterns.
• 4.5-18. Prior to the issuance of grading permits, plans for those areas that have been designated to have highly expansive soils shall be submitted to the City Engineer for review and approval. Measures to control expansive soils include overexcavation of the expansive soils/bedrock and replacement with less expansive fill soils; proper design of foundations, slabs, streets and other improvements subject to the influence of these soils; selective grading techniques to place more highly expansive soils well below foundation elements; employment of pre -saturation techniques to lessen expansion potential; and control of surface and subsurface drainages to prevent moisture variations.
• 4.5-19. At the completion of grading, specific testing for expansion potential shall be performed by a qualified geologist on the as-graded near surface materials and shall identify the findings in a report which would be submitted to the City Engineer for review and approval.
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3.6.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
GEOLOGY AND SOILS – Would the project:
a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent Alquist -Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42.
ii) Strong seismic ground shaking?
iii) Seismic-related ground failure, including liquefaction?
iv) Landslides?
b) Result in substantial soil erosion or the loss of topsoil?
c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse?
d) Be located on expansive soil, as defined in Table 18 -1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property?
e) Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of waste water?
f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
Would the Project:
a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? ii) Strong seismic ground shaking?
No Substantial Change from Previous Analysis. Based on a review of updated mapping of faults provided by the USGS, only the Simi-Santa Rosa fault zone occurs in the vicinity of the Project Site, which is the same as was disclosed in the 2011 EIR (USGS 2025a). 1034
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The Proposed Project would not result in impacts to any new areas of the Project Site that would increase impacts related to the rupture of a known earthquake fault or related to strong seismic ground shaking. The Proposed Project would move the proposed residential units from areas that are south of Lost Canyons Drive, closer to the fault zone, to areas north of Lost Canyons Drive that are further from the fault zone.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
iii) Seismic-related ground failure, including liquefaction? No Substantial Change from Previous Analysis. As identified in the 2011 EIR, the 2025 Seismic Hazard Zone Mapping maintained by the California Geological Survey shows that much of the Project Site, including the impact footprint for the Proposed Project, are located within liquefaction zones , which are areas where liquefaction may occur during a strong earthquake (CGS 2025a). The Proposed Project would implement mitigation measures 4.5 - 9 through 4.5 -19 from the 2011 EIR, which would reduce potentially signi ficant impacts related to seismic-related ground failure, including liquefaction, to less than significant levels. The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not expand impacts into any new areas that are prone to landslides that were not previously evaluated.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
iv) Landslides?
No Substantial Change from Previous Analysis. As identified in the 2011 EIR, the 2025 Seismic Hazard Zone Mapping maintained by the California Geological Survey shows that much of the Project Site is susceptible to landslides; however, the portion of the Project Site that would be developed by the Proposed Project contains much fewer landslide susceptible areas as there are south of Lost Canyons Drive. T he Proposed Project would implement mitigation measures 4.5 -9 through 4.5 -19 from the 2011 EIR, which wou ld reduce potentially significant impacts related to seismic-related ground failure, including landslides, to less than significant levels. The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not expand impacts into any new areas that are prone to landslides that were not previously evaluated.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Result in substantial soil erosion or the loss of topsoil? No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would result in temporary and permanent impacts related to soil erosion.
Temporary erosion impacts would result from clearing, grubbing, and grading that would occur in the Project Site. The Proposed Project would be required to comply with applicable 1035
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laws requiring the development and implementation of a Storm Water Pollution Prevention Plan (SWPPP), which would minimize short -term erosion impacts. Given that the Proposed Project would result in less ground disturbance than would the Approved Project, soil erosion would be less for the Proposed Project than for the Approved Project.
During operation of the Proposed Project, the Proposed Project would result in increased impervious surface coverage in the Project Site when compared to existing conditions, which would have the potential to increase erosion when compared to no project conditions.
However, the Proposed Project would result in the addition of less impervious surface than would the Approved Project, given the overall reduction in impacts that would occur with the Proposed Project when compared to the Approved Project. Also, as with the Approved Project, the Proposed Project would be required to implement operational best management practices related to water quality that would reduce these impacts.
The Proposed Project would not change the impacts related to the proposed water tank in the Project Site , and mitigation measure 4.5 -8 would still be applicable to the Proposed Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the Project and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would result in potentially significant impacts related to soil instability, including lateral spreading, subsidence, liquefaction, and collapse prior to the implementation of mitigation. As disclosed in the 2011 EIR, the Project Site contains a variety of soil types, some of which are prone to landslides, lateral spreading, subsidence, liquefaction, and collapse. Mitigation measure 4.5-9 through mitigation measure 4.5-19 that were specified for the Approved Project in the 2011 EIR to reduce impacts would also apply to the Proposed Project. The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not expand impacts into any new areas that are geologically unstable that were not previously evaluated.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) h) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property? No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would result in potentially significant impacts related to soil instability, including lateral spreading, subsidence, liquefaction, and collapse prior to the implementation of mitigation. As disclosed in the 2011 EIR, the Project Site contains a variety of soil types, some of which are prone to landslides, lateral spreading, subsidence, liquefaction, and collapse. Mitigation measure 4.5-9 through mitigation measure 4.5-19 that 1036
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were specified for the Approved Project in the 2011 EIR to reduce impacts would also apply to the Proposed Project. The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not expand impacts into any new areas that are geologically unstable that were not previously evaluated.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
e) Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater?
No Substantial Change from Previous Analysis . The Proposed Project does not propose any new septic tanks or other wastewater disposal systems.
According to the 2011 EIR, t he golf course clubhouse and the residence at the bunkhouse had septic systems for their sewer discharge . However, according to the DTSC’s EnviroStor mapper, it appears that these septic tanks have since been removed (DTSC 2025a).
Therefore, the Proposed Project would not result in any new significant impacts related to this threshold.
f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
No Substantial Change from Previous Analysis . A paleontological assessment was prepared for the Approved Project, which determined that at least 18 vertebrate fossil localities yielding more than 2,400 individual vertebrate specimens have been documented within the Project Site and in its immediate vi cinity. The 2011 EIR determined that mitigation measures were required related to paleontological resources given the paleontological sensitivity in the Project Site. Mitigation measure 4.4. -8 through mitigation measure 4.4-11 were required for the Approved Project to mitigate impacts related to archaeological resources to less than significant levels . The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not expand impacts into any new areas that are paleontologically sensitive that were not previously evaluated.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to geology and soils that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to geology and soils continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.7 GREENHOUSE GAS EMISSIONS
3.7.1 2011 EIR
Although the topic of greenhouse gas emissions was not part of the Appendix G of the State CEQA Guidelines at the time the 2011 EIR was prepared, the issue of GHG emissions and climate change impacts is not new information that was not known or could not have been known at the time of the certification of the 2011 EIR.
The United Nations Framework Convention on Climate Change (UNFCCC) was established in 1992. The regulation of GHG emissions to reduce climate change impacts was extensively debated and analyzed throughout the early 1990s. The studies and analyses of this i ssue resulted in the adoption of the Kyoto Protocol in 1997. Many EIRs from 2006 and earlier described how climate change (often called global warming) would result in sea -level rise and other environmental changes. At the time of approval of the 2011 EIR, the contribution of GHG emissions to climate change was a prominent issue of concern. Therefore, the fact that GHG emissions could have a significant adverse environmental impact was known at the time the General Plan was approved and the 2011 EIR was certified.
Greenhouse gas emissions was not evaluated as a standalone topic in the 2011 EIR given that it was not part of the Appendix G of the State CEQA Guidelines at the time that the 2011 EIR was prepared. However, the topic of greenhouse gas emissions for the Approved Project was evaluated in the 2011 EIR as a part of the air quality analyses contained in Section 4.2 of the 2011 EIR.
Overall related to greenhouse gas emissions, the 2011 EIR disclosed that the Approved Project would result in operational greenhouse gas emissions from automobile s and other sources such as utilities The 2011 EIR also quantified the anticipated greenhouse gas emissions for construction of the Approved Project. The 2011 EIR determined that the Approved Project would result in less than significant impacts related to greenhouse gas emissions with implementation of mitigation measure 4.2 -5, which requires that measures from the BuildItGreen GreenPoint Checklist be incorporated into the Approved Project’s design.
Mitigation Program
The 2011 EIR did not include mitigation measures directly related to greenhouse gas emissions.
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3.7.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
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Previous
Analysis
GREENHOUSE GAS EMISSIONS – Would the project:
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases?
The responses in this section are based on a Greenhouse Gas Emissions Technical Memorandum that was prepared for the Proposed Project by Michael Baker International in January 2025 (Michael Baker International 2025c).
Would the Project:
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases?
No Substantial Change from Previous Analysis.
Project-Related Greenhouse Gas Emissions
The Proposed Project would not result in the addition of any new land uses compared to what was previously analyzed in the 2011 EIR.
Project-related GHG emissions would include emissions from direct and indirect sources.
Direct project-related GHG emissions would include emissions from construction activities, area sources, mobile sources, and refrigerants, while indirect sources would include emissions from energy consumption, water demand, and solid waste generation. The CalEEMod model was used as a part of the development of the Proposed Project’s Air Quality Technical Memorandum to calculate project-related GHG emissions that would result from the Proposed Project (Michael Baker International 2025a) . The Proposed Project would be subject to mitigation measure 4.2 -5 from the 2011 EIR, which aims to achieve a Green Building rating for new residential structures.
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Direct Project-Related Source of Greenhouse Gases
Construction Emissions
As discussed in the Air Quality Technical Memorandum, the Proposed Project would result in a total of 3,557 MTCO2e of emissions during construction. Construction GHG emissions were amortized over 30 years (i.e., total construction emissions divided by the lifetime of the project, assumed to be 30 years). The amortization takes into consideration the temporary nature of construction activities. As shown in the Air Quality Technical Memorandum , construction of the Proposed Project was modeled and is estimated to generate approximately 118.57 MTCO2e of emissions per year when amortized over 30 years. Given the smaller footprint, the Proposed Project would result in less grading and would thereby result in less construction greenhouse gas emissions than would the Approved Project.
Mobile Source Emissions
According to the Transportation Technical Memorandum, the Proposed Project would result in 3,483 daily trips per day (Michael Baker International 2025 c). As a result, the Proposed Project would result in a total of 4,000 MTCO2e per year of GHG emissions from mobile source (Michael Baker International 2025a). Given the same number of residential units would be developed, the Proposed Project would result in similar mobile source emissions as would the Approved Project.
Area Source Emissions
Area source emissions would be generated due to an increased demand for consumer products, architectural coating, and landscaping associated with the development of t he Proposed Project. As shown in the Air Quality Technical Memorandum, the Proposed Project would result in a total of 4.53 MTCO2e per year of GHG emissions from area source . Given the same number of residential units would be developed, the Proposed Project would result in similar source emissions as would the Approved Project.
Refrigerants
Refrigerants are substances used in equipment for air conditioning and refrigeration. Most of the refrigerants used today are HFCs or blends thereof, which can have high global warming potential values. All equipment that uses refrigerants has a charge siz e (i.e., quantity of refrigerant the equipment contains), and an operational refrigerant leak rate, and each refrigerant has a global warming potential that is specific to that refrigerant. CalEEMod quantifies refrigerant emissions from leaks during regula r operation and routine servicing over the equipment lifetime, and then derives average annual emissions from the lifetime estimate. As noted in the Air Quality Technical Memorandum, the Approved Project would result in 0.85 MTCO2e per year of GHG emissions from refrigerants. Given the same number of residential units would be developed, the Proposed Project would result in similar emissions of refrigerants as would the Approved Project. 1040
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Indirect Project-Related Source of Greenhouse Gases
Energy Consumption
Energy consumption emissions were calculated for the Proposed Project using the CalEEMod model and project -specific land use data as a part of the development of the Air Quality Technical Memorandum. The Proposed Project would be required to comply with the most current Title 24. Title 24 provides minimum efficiency standards related to various building features, including appliances, water and space heating and cooling equipment, building insulation and roofing, a nd lighting. Additionally, the Proposed Project would include solar -ready roofs. Overall, the Proposed Project would indirectly result in 1,205 MTCO2e per year of GHG emissions due to energy consumption.
Water Demand
According to the Air Quality Technical Memorandum prepared for the Proposed Project , emissions from indirect impacts from water use for the Proposed Project would result in
90.6 MTCO2e per year of GHG emissions. Given the same number of residential units would be developed, the Proposed Project would result in similar emissions related to water demand as would the Approved Project.
Solid Waste
Solid waste associated with operations of the Lost Canyons Project would result in 91.4 MTCO2e per year of GHG emissions . Given the same number of residential units would be developed, the Proposed Project would result in similar emissions related to solid waste as would the Approved Project.
Total Project-Related Sources of Greenhouse Gases
As shown in the Air Quality Technical Memorandum, the total amount of the Proposed Project’s GHG emissions, from direct and indirect sources combined would total approximately 5,510.95 MTCO2e per year . According top the Air Quality Technical Memorandum, these emissions would be lower than what was previously disclosed in the 2011 EIR for the Approved Project.
Consistency With Applicable Plans
The consistency analysis for the Approved Project within the 2011 EIR is based on the AB 32 Climate Change Scoping Plan, also known as 2008 Scoping Plan. However, this document has since been updated, with the most recent approved iteration being the 2022 Scoping Plan.
The GHG plan consistency analysis for the project is based on the Proposed Project’s consistency with the CARB’s 2022 Scoping Plan, SCAG’s 2020 -2045 RTP/SCS, and City’s General Plan as well as the City’s CAP.
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Consistency With 2022 Scoping Plan
The 2022 Scoping Plan identifies reduction measures necessary to achieve the goal of carbon neutrality by 2045 or earlier. Actions that reduce GHG emissions are identified for each AB 32 inventory sector. An evaluation of applicable reduction actions/strategies by emissions source category is provided for the Proposed Project within the Air Quality Technical Memorandum. As described therein, the Proposed Project would be consistent with the applicable reduction actions/strategies outlined in the 2022 Scoping Plan.
Consistency With the SCAG 2020-2045 RTP/SCS
On September 3, 2020, the Regional Council of SCAG formally adopted the 2020 -2045 RTP/SCS. The 2020- 2045 RTP/SCS includes performance goals that were adopted to help focus future investments on the best -performing projects, as well as different strategies to preserve, maintain, and optimize the performance of the existing transportation system. The SCAG 2020-2045 RTP/SCS is forecast to help California reach its GHG reduction goals by reducing GHG emissions from passenger cars by eight percent below 2005 le vels by 2020 and 19 percent by 2035 in accordance with the most recent CARB targets adopted in March 2018. Five key SCS strategies are included in the 2020-2045 RTP/SCS to help the region meet its regional VMT and GHG reduction goals, as required by the State. Table 3¸ Consistency with the 2020 -2045 RTP/SCS shows the project’s consistency with these five strategies found within the 2020-2045 RTP/SCS.
The 2024-2050 RTP/SCS (Connect SoCal 2024) was adopted on April 4, 2024. However, CARB concluded that the technical methodology SCAG used to quantify the GHG emission reductions for the Connect SoCal 2024 does not operate accurately. At the time of preparation of this EIR Addendum, CARB has not made its determination. Review by CARB is limited to acceptance or rejection of SCAG’s determination that its SCS would, if implemented, achieve the region’s GHG emissions reduction target. If CARB rejects SCAG’s determination of meeting the GHG emission target, SCAG would need to revise the SCS or adopt an alternative planning strategy demonstrating the ability to achieve the target. As such, until CARB makes the decision, Connect SoCal 2024 is not a fully adopted do cument and is potentially subject to further updates, especially from the GHG reduction perspective of the methods and assumptions of the calculation of Auto Operating Costs (AOC)10, induced travel, electric vehicle incentives, job center parking and parki ng deregulation, off -model strategy assumptions, and emissions factors. As CARB has not made the decision at the time of preparation of the Air Quality Technical Memorandum, the consistency analysis shown in the Air Quality Technical Memorandum evaluates the 2020-2045 RTP/SCS. As shown in the Air Quality Technical Memorandum, the Proposed Project would be consistent with the GHG emission reduction strategies contained in the 2020-2045 RTP/SCS.
Consistency with General Plan and CAP
The City’s General Plan contains several goals related to GHG emissions reduction. Similarly, the City’s CAP contains goals intended to support sustainable development within the City .
Implementation of the City’s CAP would contribute to a reduction in the City’s overall GHG emissions. An analysis of the Proposed Project’s consistency with applicable policies from the CAP and General Plan are provided in the Air Quality Technical Memorandum, which determined the Proposed Project would be consistent.
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Conclusion
The Proposed Project would not result in any new or substantially increased effects related to greenhouse gas emissions that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to greenhouse gas emissions continue to apply; h owever, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.8 HAZARDS AND HAZARDOUS MATERIALS
3.8.1 2011 EIR
During development of t he 2011 EIR, a Phase I environmental site assessment (ESA) was prepared to identify the presence of hazardous materials within soil and groundwater within the Project Site. The Phase I ESA included a search of the California Department of Toxic Substances Control database , which indicated that there were two underground storage tanks (UST), five leaking underground storage tanks (LUST), and one state priority site (MaruFuji/Big Sky, Ltd., site located at Tapo and Dry Canyons, which in cludes a thousand acres of abandoned oil wells) located less than 1 mile from the Project Site boundaries.
The 2011 EIR disclosed that since there are drill sites within the Project Site, there would be the potential for impacts relating to future oil operations that would result from the Approved Project. Impacts would be less than significant with implementation of mitigation measures 4.6-1 through 4.6-4.
As required by m itigation measure 4.6 -1, in the event that an abandoned oil well is encountered during construction activities, grading and earthmoving activities in the immediate area (within 50 feet) shall cease and the City Engineer and the regional DOGGR office in Ventura shall be notified imm ediately of the discovery. The oil well casing shall be checked for leaking oil or gases. The DOGGR representative shall determine appropriate actions, up to and including re-abandonment of the oil well casing.
As required by mitigation measure 4.6 -2, prior to any issuance of grading permits, soil sampling shall be conducted at the locations of the potential oil wells located within the impact footprint of the Approved Project. The results of the soil sampling shall be submitted to the Ventura County Environmental Health Department (VCEHD). If sampling identifies contaminated soils, such soils shall be remediated under the supervision of—and as required by and subject to the approval of—the VCEHD
As required by mitigation measure 4.6-3, prior to the issuance of grading permits, the top of the abandoned wells located within 50 feet of a building pad should be a minimum of 10 feet below grade and wells located below structures will require proper venting under supervision of the City Engineer.
As required by mitigation measure 4.6-4, prior to the issuance of grading permits, mud pits and any existing fill associated with past oil field activities (i.e., roads and drill pads), if encountered, shall be evaluated and documented by a City-approved environmental scientist and the fill approved by a City geologist as to the potential impact to the proposed development.
With implementation of mitigation measures 4.6-1 through 4.6-4, the 2011 EIR determined that the Approved would result in less than significant impacts related to oil wells in the Project Site.
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The 2011 EIR identified that the Approved Project had the potential to result in impacts related to hazardous soil contamination from prior site land uses. As a result, the Approved Project would implement mitigation measure 4.6-5 to minimize impacts, which requires that prior to any issuance of grading permits, soil sampling shall be conducted at locations of the existing golf courses. If sampling identifies contaminated soils, such soils shall be remediated under the supervision and subject to the approval of the VCEHD.
Related to exposing people or structures to a significant risk of loss, injury, or death involving wildland fires, the 2011 EIR determined that the Approved Project would result in significant impacts requiring mitigation. As such, mitigation measures 4.12-1 through 4.12-10 would be implemented, which would reduce these impacts to less than significant levels.
As required by mitigation measure 4.12 -1, prior to issuance of grading plans the applicant shall prepare and submit to the City Planning Department for review and approval a construction traffic control plan which would minimize potential impacts to emergency service providers.
As required by mitigation measure 4.12-2, during all grading and site clearance activities, the applicant’s general contractor shall ensure that all construction traffic is restricted to using Tapo Canyon Road and Lost Canyons Drive only per the approved traffic control plan, and all earth -moving equipment shall be equipped with spark arrestors and at least two portable fire extinguishers per vehicle. All equipment used in the vegetation clearance phase shall be eq uipped with spark arrestors and best availa ble fire safety technology. The vegetation-clearance activities shall be coordinated with and approved by the VCFPD.
Implementation of 4.12-2 would serve to reduce potential for the ignition of wildfires during construction and to maintain evacuation routes during construction.
As required by mitigation measure 4.12.-3, prior to the issuance of building permits, the applicant shall submit proof that all structures adjacent to open space shall be designed to satisfy at least a 1-hour fire-resistant rating and to meet other requirements, As required by mitigation measure 4.12-4, p rior to tentative map approval, the applicant shall submit drawings indicating that adequate access points, water mains, fire hydrants, valve connections, and other fire protection facilities is provided as required to VCFPD for review and approval.
As required by mitigation measure 4.12-5, p rior to issuance of building permits, the applicant shall submit fire protection improvement plans to the City of Simi Valley and VCFPD for review and approval. Upon approval of the plans, the VCFPD shall certify in writing to the City Department of Engine ering that the proposed fire protection improvements have been found to be satisfactory.
As required by mitigation measure 4.12-6, p rior to issuance of occupancy permits, the applicant shall submit a plan for delineating building addresses for purposes of emergency response to the City of Simi Valley and VCFPD for review and approval. 1045
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As required by mitigation measure 4.12-7, prior to issuance of building permits tentative map approval, the applicant shall pay the required fire protection facilities fees for each applicable structure.
As required by mitigation measure 4.12-8, p rior to the issuance of building permits, the applicant shall provide proof to the City Building Department of compliance with all applicable building and fire code requirements for items such as types of roofing materials, building construction, brush cle arance, fire hydrant flows, hydrant spacing, access and design, fire sprinkler systems, and other hazard reduction programs, as set forth by the VCFPD.
As required by mitigation measure 4.12-9, p rior to tentative map approval, the applicant shall submit proposed street alignments, grades, widths, lengths, and turning radii to VCFPD and City Engineer for review and approval.
As required by mitigation measure 4.12-10, prior to tentative map approval, the applicant shall provide landscape/fuel modification plans prepared by a licensed landscape architect to the VCFPD for review and approval. The use of drought tolerant, fire -resistant, native vegetation shall be incorporated into the landscape/fuel modification plans.
With implementation of mitigation measures 4.12-1 through 4.12-10, the Approved Project’s impacts related to exposing people or structures to a significant risk of loss, injury, or death involving wildland fires would be reduced to less than significant levels.
The 2011 EIR stated that due to the geography of the area, there would be inadequate two - way radio system coverage for public health and safety agencies , which would result in potentially significant impacts prior to mitigation. The 2011 EIR required implementation of mitigation measure 4.6 -6, which requires that prior to the issuance of a Zoning Clearance, the applicant shall conduct a signal strength co verage test to determine existing two -way radio coverage in the Project area. If two-way radio coverage is determined to be inadequate, the applicant shall work with the appropriate public health and safety agencies’ representatives (City of Simi Valley Police Department, Ventura County Fire Department, Ventura County W aterworks District No. 8, and the Sanitation Services Division of the Department of Public Works) to engineer, construct, install, test and implement additional two-way radio sites/systems required to extend the coverage of local public health and safety c ommunication systems into the Project area. With implementation of mitigation measure 4.6 -6, the Approved Project was determined to result in less than significant impacts related to this topic.
The 2011 EIR stated that there was potential for workers to be exposed to Valley Fever during construction of the Approved Project. The 2011 EIR specified implementation of mitigation measures 4.6 -7 through 4.6 -9 to reduce the significance of impacts related to Valley Fever to less than significant levels.
Mitigation measure 4.6-7 requires that work crews use respirators during project clearing, grading, and excavation operations, in accordance with California Division of Occupational Safety and Health regulations. Also, the cabs of grading and construction equipment shall be air conditioned as required by this measure.
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As required by mitigation measure 4.6-8, construction roads shall be paved, when possible, to reduce fugitive dust and potential exposure to the fungus; or the access road into the project site shall be paved or treated with environmentally safe dust control agents and where unpaved shall be wetted two times per day to minimize dust.
Mitigation measure 4.6-9 requires that, w here acceptable to the Ventura County Fire Protection District, weed growth shall be controlled by mowing instead of discing, thereby leaving the ground undisturbed; a mulch covering shall also be used when possible.
Mitigation Program
• 4.6-1. In the event that an abandoned oil well is encountered during construction activities, grading and earthmoving activities in the immediate area (within 50 feet) shall cease and the City Engineer and the regional DOGGR office in Ventura shall be notified immediately of the discovery. The oil well casing shall be checked for leaking oil or gases. The DOGGR representative shall determine appropriate actions, up to and including re -abandonment of the oil well casing. Upon approval of the DOGGR representation, and the City Engineer, and after appropriate remediation efforts regarding the well have been completed, grading and earthmoving may resume. • 4.6-2. Prior to any issuance of grading permits, soil sampling shall be conducted at the locations of the potential oil wells located within the project boundaries. The results of the soil sampling shall be submitted to the Ventura County Environmental Hea lth Department (VCEHD). If sampling identifies contaminated soils, such soils shall be remediated under the supervision of—and as required by and subject to the approval of—the VCEHD.
• 4.6-3. Prior to the issuance of grading permits, the top of the abandoned wells located within 50 feet of a building pad should be a minimum of 10 feet below grade (California Code of Regulations, Title 14, Division 2, Chapter 3, Article 3, Section 1723.5) and wells located below structures will require proper venting under supervision of the City Engineer (Department of Conservation Well Review Program Item 6).
• 4.6-4. Prior to the issuance of grading permits, mud pits and any existing fill associated with past oil field activities (i.e., roads and drill pads), if encountered, shall be evaluated and documented by a City approved environmental scientist and the fill approved by a City geologist as to the potential impact to the proposed development. • 4.6-5. Prior to any issuance of grading permits, soil sampling shall be conducted at locations of the existing golf courses. If sampling identifies contaminated soils, such soils shall be remediated under the supervision and subject to the approval of the VCEHD.
• 4.6-6 Prior to the issuance of a Zoning Clearance, the applicant shall conduct a signal strength coverage test to determine existing two -way radio coverage in the Project Site. If two -way radio coverage is determined to be inadequate, the applicant shall work with the appropriate public health and safety agencies’ representatives (City of Simi Valley Police Department, Ventura County Fire Department, Ventura County 1047
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Waterworks District No. 8, and the Sanitation Services Division of the Department of Public Works) to engineer, construct, install, test and implement additional two-way radio sites/systems required to extend the coverage of local public health and safety communication systems into the Project Site.
• 4.6-7. Work crews shall use respirators during project clearing, grading, and excavation operations, in accordance with California Division of Occupational Safety and Health regulations. The cabs of grading and construction equipment shall be air conditioned.
• 4.6-8. Construction roads shall be paved, when possible, to reduce fugitive dust and potential exposure to the fungus; or the access road into the Project Site shall be paved or treated with environmentally safe dust control agents and where unpaved shall be wetted two times per day to minimize dust.
• 4.6-9. Where acceptable to the Ventura County Fire Protection District, weed growth shall be controlled by mowing instead of discing, thereby leaving the ground undisturbed; a mulch covering shall also be used when possible.
3.8.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
HAZARDS AND HAZARDOUS MATERIALS – Would the project:
a) Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one -quarter mile of an existing or proposed school?
d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a significant hazard to the public or the environment?
e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or a public use airport, would the project result in a safety hazard or excessive noise for people residing or working in the project area?
f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
Would the Project:
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a) Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
No Substantial Change from Previous Analysis. The Proposed Project would occur within the same impact footprint as was approved for the Approved Project; therefore, the Proposed Project would not result in any new soils or demolition materials needing to be transported from the Project Site that could contain hazardous materials.
The Proposed Project would include similar land uses as were evaluated for the Approved Project. As such, the Proposed Project and the Approved Project would result in similar transport, use, and disposal of domestic hazardous materials as was evaluated in the 2011 EIR.
In conclusion, the Proposed Project would not result in any new significant impacts related to these thresholds.
c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? No Substantial Change from Previous Analysis. There are no new schools that are located within 0.25 mile of the impact footprint for the Proposed Project. Also, the Proposed Project would result in similar land uses to the land uses that were evaluated for the Approved Project. As such, the Proposed P roject and the Approved Project would result in similar emissions and handling of hazardous materials, which would be minimal.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a significant hazard to the public or the environment?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project has the potential to result in impacts related to hazardous soil contamination from prior site land uses. As a result, the Approved Project would implement mitigation measure 4.6-5 to minimize impacts, which requires that prior to any issuance of grading permits, soil sampling shall be conducted at locations of the existing golf courses. If sampling identifies contaminated soils, such soils shall be remediated under the supervision and subject to the approval of the VCEHD.
Related to exposing people or structures to a significant risk of loss, injury, or death involving wildland fires, the Proposed Project would result in significant impacts requiring mitigation to a similar extent as would the Approved Project . As such, mitigation measures 4.12 -1 1049
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through 4.12-10 would be applicable to the Proposed Project , which would reduce these impacts related to this threshold to less than significant levels.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the Project result in a safety hazard or excessive noise for people residing or working in the project area?
No Substantial Change from Previous Analysis . The Project Site is not located within an airport land use plan or within two miles of a public airport or public use airport.
As such, the Proposed Project would not result in any new significant impacts related to this threshold.
f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
No Substantial Change from Previous Analysis. The 2011 EIR determined that the Approved Project would not impair the implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. The 2011 EIR discussed that the Proposed Project would include adequate p rimary and secondary access roads, which would allow for adequate access during an emergency such as a wildland fire.
The Proposed Project would result in similar impacts related to emergency evacuation as would the Approved Project given that the Proposed Project would result in similar roadway infrastructure being developed to evacuate the Project Site and because the A pproved Project would not result in an increase in the number of units or individuals that would need to evacuate the Project Site when compared to the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would occur entirely within a Project Site that is designated as a very high fire hazard severity zone by CalFire (CalFire 2025a).
The Proposed Project would potentially result in increased exposure of people and buildings to wildland fires, as would occur with the Approved Project.
To mitigate impacts related to wildfire to less than significant levels, the 2011 EIR included mitigation measures 4.12-1 through 4.12-10, which would also be applicable to the Proposed Project. With implementation of these measures, the Proposed Project w ould have similar impacts related to this threshold as would the Approved Project. 1050
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In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to hazards and hazardous materials that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to hazards and hazardous materials continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR. 1051
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3.9 HYDROLOGY AND WATER QUALITY
3.9.1 2011 EIR
The 2011 EIR described that the Project Site is located within the boundaries of the VCWPD.
As described in the 2011 EIR, the Approved Project , during both construction and operational phases would have the potential to affect both the volume and quality of runoff from the Project Site.
During the construction phase of the Approved Project, the use of heavy equipment and the disturbance of soil on the Project Site would have the potential to substantially degrade the water quality and increase the volume of runoff. Potential construction impacts would be reduced by the implementation of the best management practices (BMPs) outlined in the storm water pollution prev ention plan (SWPPP). The implementation of these measures, along with enforcement of the appropriate BMPs for construction, wou ld reduce the construction-related degradation of water quality to less than significant. Mitigation measures applicable to construction -related water quality are provided as mitigation measures 4.7-1 through 4.7-8.
As required by mitigation measure 4.7-1, prior to issuance of a grading permit, the applicant shall obtain an NPDES General Construction Permit (CAS00002). This permit requires a SWPPP that specifies BMPs to reduce erosion of disturbed soils of more than 1 acre. A copy of the permit shall be submi tted to the City Public Works Department prior to the start of grading activities.
As required by mitigation measures 4.7-2, d uring site preparation and construction, the contractor shall minimize disturbance of natural groundcover on the project site until such activity is required for grading and construction purposes. During grading operations, the developer shall designate a representative responsible for NPDES compliance. If determined necessary by the City Engineer, the NPDES representative shall be present on the project site Monday through Friday, on all other days when the probab ility of rain is 40 percent or higher, and prior to the start of and during all grading or clearing operations until the release of grading bonds. The NPDES representative shall have full authority to hire personnel, bind the developer in contracts, rent e quipment, and purchase materials to the extent needed to effectuate best management practices (BMPs). The NPDES representative shall provide proof to the City Engineer of attendance and satisfactory completion of courses satisfactory to the City Engineer totaling no less than 8 hours directed specifically to NPDES compliance and effective use of BMPs. Proof of such attendance and completion shall be provided to the City Engineer prior to employment and/or designation of the NPDES representative.
As required by mitigation measures 4.7-3, the applicant shall prepare a runoff management plan (RMP) to be submitted to the City Engineer for review and acceptance prior to the issuance of grading permits. The Ventura County Watershed Protection District –adopted Master Drainage Plan and the Ventura County Watershed Protection District Design and Hydrology Manuals shall be used as the basis for the RMP, channel stabilization, or other City-approved measure shall be implemented.
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As required by mitigation measures 4.7-4, during site preparation, grading, and construction, the contractor shall minimize disturbance of natural groundcover on the project site until such activity is required for grading and construction purposes.
As required by mitigation measures 4.7-5, prior to issuance of a grading permit, the applicant shall have prepared a Storm Water Quality Urban Impact Mitigation Plan (SQUIMP) and include non-structural, source control, and structural best management practices (BMPs). A certified erosion and sediment control professional or qualified civil engineer shall prepare the SQUIMP. The SQUIMP shall be submitted to the City Engineer for review and acceptance.
The development of the SQUIMP shall conform to the current Ventura County National Pollutant Discharge Elimination System permit, the SQUIMP standards, and the Technical Guidance Manual for Storm Water Quality Control Measures.
As required by mitigation measure 4.7-6, p rior to the issuance of a grading permit, the applicant shall file a Notice of Intent (NOI) with the Los Angeles Regional Water Quality Control Board, thereby providing notification and intent to comply with the State of California general permit. Prior to issuance of the first grading permit, a Storm Water Pollution Prevention Plan (SWPPP) must be completed for on -site and associated off -site construction activities. A copy of the permit shall be submitted to the C ity Public Works Department prior to the start of grading activities. A copy of the SWPPP must be available and implemented at the construction site at all times. The SWPPP outlines the source control and/or treatment control best management practices (BMP s) that will avoid or mitigate runoff pollutants at the construction site to the maximum extent practicable.
As required by mitigation measure 4.7-7, prior to the approval of tentative tract maps, the applicant will provide the exact number of debris basins and the locations and size of these debris basins to adequately mitigate the erosion of sediment. The size, locations, and number of debris basins will be subject to review and acceptance of the City Engineer As required by mitigation measure 4.7-8, the accumulation of sediment and organic buildup shall be dredged from the debris basins and the Tapo Canyon regional detention basin as necessary to comply with SQUIMP requirements. The regional detention basin would be the responsibility of the VCWPD for ongoing regional flood control and maintenance. The Project development basins, including surface drains, storm drains, detention basins, debris basins, and stormwater pollution control devices shall be the responsibility of the homeowners association (HOA). The HOA, through a maintenance agreement with the VCWPD, will be responsible for certai n designated maintenance responsibilities related to the public open space properties to be dedicated to the VCWPD.
The Approved Project was disclosed in the 2011 EIR as being planned to maintain the characteristics of the natural drainage system to the maximum extent feasible. The 2011 EIR stated that the Approved Project 's storm drainage system was designed to achieve two primary objectives: (1) meet storm drainage design requirements of the City of Simi Valley and VCWPD and (2) minimize impacts to the existing channels and to support the natural vegetation and wildlife.
The City’s Master Plan of Drainage has designated a location of a regional detention basin in Dry Canyon. The Approved Project amended the Master Plan of Drainage through the 1053
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dedication of land, in accordance with Ventura County Watershed Protection District standards, for a regional detention basin in Tapo Canyon. At the time of the development of the 2011 EIR, there were two potential alternatives for the Tapo Canyon watershed and five potential alternatives for the Dry Canyon watershed that were being considered by the County to handle the potential increase in runoff from the proposed development.
Infrastructure to be constructed, under these alternatives include d a detentio n basin and channel improvements that would mitigate potential impacts related to water quality, runoff volumes, groundwater recharge, and flooding. The County selected the Tapo Canyon alternative that included a regional detention basin and channel improvements . The Dry Canyon alternatives, which included channel improvements, were determined to have lower cost-benefit-cost ratios as compared to a Dry Canyon Region basin. As such, the Approved Project was required to construct on-site drainage improvements to the standards of the City of Simi Valley, VCWPD, and applicable regulatory agencies. Drainage improvements were to be designed and constructed to mitigate flooding impacts to the existing watersheds that would result from the Approved Project.
The 2011 EIR determined that the Approved Project would result in potentially significant impacts related to contributing runoff water that would exceed the capacity of existing or planned storm water drainage systems or that would provide substantial additional sources of polluted runoff . The Approved Project would add new impervious surface which would generate additional stormwater for receiving waters and stormwater facilities. As required by mitigation measure 4.7-9, the applicant shall dedicate land to VCWPD for development of the Tapo Canyon regional detention basin, and participate in onsite and offsite Dry and Tapo Canyon Watershed regional drainage facilities resulting from the proposed deletion of the Dry Canyon Regional Detention Basin from the City’s Master Plan of Drainage as determined with the Tentative Tract Map approval process. It is noted that the Project is not responsible for constructing the regional basin. Through compliance with existing regulations and with implementation of mitigation measure 4.7-9, the Approved Project would result in less than significant impacts related to runoff.
Overall, with implementation of the mitigation measures 4.7-1 through 4.7-14, the Approved Project’s impacts related to water quality and hydrology would be reduced to less than significant levels.
Mitigation Program
• 4.7-1. Prior to issuance of a grading permit, the applicant shall obtain an NPDES General Construction Permit (CAS00002). This permit requires a SWPPP that specifies BMPs to reduce erosion of disturbed soils of more than 1 acre. A copy of the permit shall be submitted to the City Public Works De partment prior to the start of grading activities.
• 4.7-2. During site preparation and construction, the contractor shall minimize disturbance of natural groundcover on the Project Site until such activity is required for grading and construction purposes. During grading operations, the developer shall designate a representative responsible for NPDES compliance. If determined necessary by the City Engineer, the NPDES representative shall be present on the Project Site Monday through Friday, on all other days when the probability of rain is 1054
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40 percent or higher, and prior to the start of and during all grading or clearing operations until the release of grading bonds. The NPDES representative shall have full authority to hire personnel, bind the developer in contracts, rent equipment, and purchase materials to the extent needed to effectuate best management practices (BMPs). The NPDES representative shall provide proof to the City Engineer of attendance and satisfactory completion of courses satisfactory to the City Engineer totaling no less than 8 hours directed specifically to NPDES compliance and effective use of BMPs. Proof of such attendance and completion shall be provided to the City Engineer prior to employment and/or designation of the NPDES representative. • 4.7-3. The applicant shall prepare a runoff management plan (RMP) to be submitted to the City Engineer for review and acceptance prior to the issuance of grading permits. The Ventura County Watershed Protection District –adopted Master Drainage Plan and the Ventura County Watershed Protection District Design and Hydrology Manuals shall be used as the basis for the RMP, channel stabilization, or other City-approved measure shall be implemented.
• 4.7-4. During site preparation, grading, and construction, the contractor shall minimize disturbance of natural groundcover on the Project Site until such activity is required for grading and construction purposes.
• 4.7-5. Prior to issuance of a grading permit, the applicant shall have prepared a Storm Water Quality Urban Impact Mitigation Plan (SQUIMP) and include non -structural, source control, and structural best management practices (BMPs). A certified erosion and sediment control professional or qualified civil engineer shall prepare the SQUIMP. The SQUIMP shall be submitted to the City Engineer for review and acceptance. The development of the SQUIMP shall conform to the current Ventura County National Pollutant Discharge Elimination System permit, the SQUIMP standards, and the Technical Guidance Manual for Storm Water Quality Control Measures.
• 4.7-6. Prior to the issuance of a grading permit, the applicant shall file a Notice of Intent (NOI) with the Los Angeles Regional Water Quality Control Board, thereby providing notification and intent to comply with the State of California general permit. Prior to issuance of the first grading permit, a Storm Water Pollution Prevention Plan (SWPPP) must be completed for on -site and associated off -site construction activities. A copy of the permit shall be submitted to the City Public Works Department prior to the start of grading activities. A copy of the SWPPP must be available and implemented at the construction site at all times. The SWPPP outlines the source control and/or treatment control best management practices (BMPs) that will avoid or mitigate run off pollutants at the construction site to the maximum extent practicable.
• 4.7-7. Prior to the approval of tentative tract maps, the applicant will provide the exact number of debris basins and the locations and size of these debris basins to adequately mitigate the erosion of sediment. The size, locations, and number of debris basins will be subject to review and acceptance of the City Engineer. • 4.7-8. The accumulation of sediment and organic buildup shall be dredged from the debris basins and the Tapo Canyon regional detention basin as necessary to comply 1055
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with SQUIMP requirements. The regional detention basin would be the responsibility of the VCWPD for ongoing regional flood control and maintenance. Storm drain facilities such as surface drains, storm drains, detention basins, debris basins, and stormwater pollution control devices shall be the responsibility of the homeowners association (HOA). The HOA, through a maintenance agreement with the VCWPD, will be responsible fo r certain designated maintenance responsibilities related to the public open space properties to be dedicated to the VCWPD. • 4.7-9. The project owner shall dedicate land to VCWPD for development of the Tapo Canyon regional detention basin, and participate in onsite and offsite Dry and Tapo Canyon Watershed regional drainage facilities resulting from the proposed deletion of the Dry Canyon Regional Detention Basin from the City’s Master Plan of Drainage as determined with the Tentative Tract Map approval process. Prior to the approval of final tentative tract maps, the applicant will dedicate the land for the Tapo Canyon Regional Basin in accordance with the standards of the Ventura County Watershed Protection District.
• 4.7-10. The SQUIMP shall include structural and/or treatment BMPs. The structural BMPs shall focus on meeting potential total maximum daily loads (TMDL) and pollutant standards for residential developments. The treatment BMPs shall conform to the Technical Guidan ce Manual for Storm Water Control Measures. The SQUIMP guidelines contained in the National Pollutant Discharge Elimination System (NPDES) Permit and Waste Discharge Requirements for Ventura County state that structural BMPs are required for all new developments. The structural BMPs shall be sized to comply with numeric sizing criteria, in accordance with City requirements, unless an alternative to provide equivalent or better treatment is accepted by the City. • 4.7-11 Prior to the issuance of grading permits, the applicant shall obtain a development permit from the City and shall meet all of the requirements of the City’s Flood Damage Protection Prevention ordinance necessary as determined by the Floodplain Admin istrator, i.e., identification of the floodplain limits and base flood elevations, minimum setback distances, and final pad and finish floor elevations. The final pad and finish floor elevations shall be certified by a registered professional engineer and provided to the Floodplain Administrator and FEMA for review and acceptance.
• 4.7-12 Drainage improvements for the project shall be designed and constructed to comply with the drainage requirements of the City of Simi Valley, VCWPD, and applicable regulatory agencies.
• 4.7.13. Prior to the issuance of tentative tract maps, a certified hydrologist/certified registered civil engineer shall review and assess the flood potential and provide pertinent recommendations regarding the seiche potential from the proposed water tank in a report that shall be certified and accepted by the District Engineer • 4.7.14. Prior to the issuance of tentative tract maps, a geotechnical firm would review the seismic design parameters for the proposed water tank. These designs shall be in accordance with the current California Building Codes (CBC) for seismic -resistant design and would be reviewed and accepted by the District Engineer. 1056
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3.9.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
HYDROLOGY AND WATER QUALITY – Would the project:
a) Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or ground water quality?
b) Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the
basin?
c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) result in substantial erosion or siltation on- or off-site;
ii) substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or offsite;
iii) create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage
systems or provide substantial additional sources of
polluted runoff; or
iv) impede or redirect flood flows?
d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
Would the Project:
a) Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or ground water quality?
No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would result in impacts to stormwater quality and quantity during both construction and operational phases of the Proposed Project.
During the construction phase of the Approved Project, the use of heavy equipment and the disturbance of soil on the Project Site would have the potential to substantially degrade the water quality and increase the volume of runoff. Potential construction impacts would be reduced by the implementation of the best management practices (BMPs) outlined in the storm water pollution prevention plan (SWPPP). The implementation of these measures, along with enforcement of the appropriate BMPs for construction, wou ld reduce the 1057
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construction-related degradation of water quality to less than significant. Mitigation measures applicable to construction -related water quality are provided as mitigation measures 4.7-1 through 4.7-8.
Also, the Proposed Project would be required to implement mitigation measure 4.7 -1 through mitigation measure 4.7-14, which are required to minimize impacts related to operational water quality effects of the Proposed Project. Also, a s detailed in the Hydrology Study prepared for the Proposed Project , the Proposed Project would collect all onsite stormwater flows via subsurface storm drains that would convey the stormwater flows to one of five on -site detention basins that would be constructed in the Project Site to treat stormwater for water quality purposes and to mitigate for increased runoff. Also, the Proposed Project would intercept drainage from approximately 155 acres of off -site area and would convey these stormwater flows via subsurface storm drain to the Proposed Project’s proposed downstream discharge points (RTM Engineering Consultants 2025a).
In conclusion, w ith implementation of these mitigation measures as well as the Proposed Project’s updated drainage design, the Proposed Project would not result in any new or increased impacts related to this threshold.
b) Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project impede sustainable groundwater management of the basin?
No Substantial Change from Previous Analysis . The Proposed Project would not involve the construction or operation of any new wells that would directly decrease groundwater supplies.
The Proposed Project would include development of new impervious surfaces in the Project Site, which would reduce the amount of groundwater recharge that can occur within the Project Site. However, due to the nominal acreage of new impervious surface that would be added by the Proposed Project , the Proposed Project would not substantially impede any sustainable groundwater management efforts for the underlying groundwater basin.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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c) Substantially alter the existing drainage pattern of the site or area, including the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) result in substantial erosion or siltation on- or off-site; ii) substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or offsite;
iii) create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff; or
iv) impede or redirect flood flows?
No Substantial Change from Previous Analysis.
Erosion
As with the Approved Project, the Proposed Project would result in temporary and permanent impacts related to soil erosion. Temporary erosion impacts would result from clearing, grubbing, and grading that would occur in the Project Site. The Proposed Project would be required to comply with applicable laws requiring the development and implementation of a Storm Water Pollution Prevention Plan (SWPPP), which would minimize short-term erosion impacts. Given that the Proposed Project would result in less ground distu rbance than would the Approved Project, soil erosion would be less for the Proposed Project than for the Approved Project.
During operation of the Proposed Project, the Proposed Project would result in increased impervious surface coverage in the Project Site when compared to existing conditions, which would have the potential to increase erosion when compared to no project conditions.
However, the Proposed Project would result in the addition of less impervious surface than would the Approved Project, given the overall reduction in impacts that would occur with the Proposed Project when compared to the Approved Project. Also, as with the Approved Project, the Proposed Project would be required to implement operational best management practices related to water quality that would reduce these impacts.
The Proposed Project would not change the impacts related to the proposed water tank in the Project Site, and mitigation measure 4.5 -8 would still be applicable to the Proposed Project.
Overall, the Proposed Project would not increase effects related to erosion when compared to the Approved Project.
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Surface Runoff
The Proposed Project would result in additional impervious surface within the Project Site; however, as discussed above, the Proposed Project would construct five new detention basins and a system of stormwater infrastructure in the Project Site to capture , convey, and retain stormwater from the 100-year storm event. Surface runoff is described in more detail in the Proposed Project’s Hydrology Study (RTM Engineering Consultants 2025a) . As such, the Proposed Project would result in similar impacts related t o surface runoff as would the Approved Project.
Flood Flows
According to the Project’s Hydrology Study, the Proposed Project would occur entirely outside of the 100-year floodplain; therefore, the Proposed Project would not increase any impacts related to impeding or redirecting flood flows ( RTM Engineering Consultants 2025a). As such, the Proposed Project would not increase effects related to flood flows when compared to the Approved Project.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
According to the 2011 EIR, the probability of a dam failure affecting the City is low.
According to the Project’s Hydrology Study, the Proposed Project would occur entirely outside of the floodplain; therefore, the Proposed Project would not increase any impacts related to impeding or redirecting flood flows (RTM Engineering Consultants 2025a). As such, the Proposed Project would not increase effects related to flood flows when compared to the Approved Project.
The potential for secondary seismic hazards, such as tsunami and seiche, is also considered very low to none because the Project Site is located away from the ocean at an elevation that is above the mapped tsunami inundation zones.
Further, the Project Site is not located adjacent to a confined body of water; therefore, the potential for seismic hazard of a seiche (an oscillation of a body of water in an enclosed basin) is considered very low to none.
Therefore, the Project would not result in new significant impacts pertaining to flood hazard, tsunami, or seiche that would release pollutants due to inundation, that were not previously analyzed, and no mitigation measures are required.
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e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would result in impacts to stormwater quality and quantity during both construction and operational phases of the Proposed Project.
During the construction phase of the Approved Project, the use of heavy equipment and the disturbance of soil on the Project Site would have the potential to substantially degrade the water quality and increase the volume of runoff. Potential construction impacts would be reduced by the implementation of the best management practices (BMPs) outlined in the storm water pollution prevention plan (SWPPP). The implementation of these measures, along with enforcement of the appropriate BMPs for construction, wou ld reduce the construction-related degradation of water quality to less than significant. Mitigation measures applicable to construction -related water quality are provided as mitigation measures 4.7-1 through 4.7-8.
Also, the Proposed Project would be required to implement mitigation measures 4.7 -1 through 4.7-14, which are required to minimize impacts related to operational water quality effects of the Proposed Project. Also, as detailed in the Hydrology Study prepar ed for the Proposed Project, the Proposed Project would collect all onsite stormwater flows via subsurface storm drains that would convey the stormwater flows to one of five on -site detention basins that would be constructed in the Project Site to treat stormwater for water quality purposes and to mitigate for increased runoff. Also, the Proposed Project would intercept drainage from approximately 155 acres of off -site area and would convey these stormwater flows via subsurface storm drain to the Proposed P roject’s proposed downstream discharge points (RTM Engineering Consultants 2025a).
In conclusion, with implementation of these mitigation measures as well as the Proposed Project’s updated drainage design, the Proposed Project would not result in any new or increased impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to hydrology and water quality that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to hydrology and water quality continue to ap ply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.10 LAND USE AND PLANNING
3.10.1 2011 EIR
The 2011 EIR evaluated the Approved Project’s consistency with applicable land use plans and policies. The 2011 EIR examined the consistency of the Approved Project with the City of Simi Valley’s General Plan. As described in the 2011 EIR, the Approved Project required revisions of the existing Whiteface Specific Plan to conform to the policies set forth in the City of Simi Valley General Plan and the Development Code.
The 2011 EIR required implementation of mitigation measures 4.8 -1 and 4. -8-2 related to land use and planning.
Mitigation measure 4.8-1 states that the number of residential units allocated within a given planning area of the Approved Project may increase above the residential units approved within the Lost Canyons Specific Plan amendment for that planning area so long as (1) the total number of residential units does not exceed 364 units and (2) there are no new significant environmental impacts not previously studied in the 2011 EIR, processed concurrently with tentative tract map/planned development permit approv als by the Director of Environmental Services.
As required by mitigation measures 4.8 -2, if the final grade of a grading plan or adjustment in the field differs from that which was approved by (a) no more than 2 feet along the project boundary when adjacent to existing homes; (b) no more than 4 feet along the project boundary when not adjacent to existing homes; (c) no more than 4 feet of increased elevation within the interior of the map; or (d) no more than 6 feet of decreased elevation within the interior of the map, the change in grading shall be approved by the City Engineer.
Mitigation Program
• 4.8-1. The number of residential units allocated within a given planning area of the Project Site may increase above the residential units approved within the Lost Canyons Specific Plan amendment for that planning area so long as (1) the total number of residential units does not exceed 364 units and (2) there are no new significant environmental impac ts not previously studied in this EIR, processed concurrently with tentative tract map/planned development permit approvals by the Director of Environmental Services.
• 4.8-2. If the final grade of a grading plan or adjustment in the field differs from that which was approved by (a) no more than 2 feet along the Project Site ’s boundary when adjacent to existing homes; (b) no more than 4 feet along the project boundary when not adjacent to existing homes; (c) no more than 4 feet of increased elevation within the interior of the map; or (d) no more than 6 feet of decreased elevati on within the interior of the map, the change in grading shall be approved by the City Engineer.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-98
ADDENDUM NO. 1 TO THE EIR
3.10.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
LAND USE AND PLANNING – Would the project:
a) Physically divide an established community?
b) Cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect?
Would the Project:
a) Physically divide an established community?
No Substantial Change from Previous Analysis. As with the Approved Project, t he Proposed Project would not result in the physical division of any established communities .
The Proposed Project would not result in the construction of new roadways or other physical infrastructure that would divide or disrupt connections amongst and between existing neighborhoods.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect?
No Substantial Change from Previous Analysis . The Proposed Project would require discretionary approvals, including the City’s approval of a General Plan Amendment, a Zone Change, a Specific Plan Amendment, a Planned Development Permit Modification, and a Tentative Map . With the City’s approvals of these discretionary requests , the Proposed Project would not result in any significant impacts related to City plans, policies, or regulations.
The number of housing units would remain the same for the Proposed Project as was previously evaluated and disclosed for the Approved Project. As such, the Proposed Project would be consistent with regional plans that are dependent upon City demographics, such as the SCAG RTP/SCS.
The Project Site is not contained within the boundaries of an adopted Habitat Conservation Plan or a Natural Communities Conservation Plan (NCCP).
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-99
ADDENDUM NO. 1 TO THE EIR
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to land use and planning that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to land use and planning continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-100
ADDENDUM NO. 1 TO THE EIR
3.11 MINERAL RESOURCES
3.11.1 2011 EIR
The 2011 EIR identified that the Project Site is located within areas designated as MRZ-3 by the California Department of Conservation. MRZ-3 zones are classified as containing mineral deposits whose significance cannot be evaluated based on available data . The Project Site lies south of a region designated as containing regionally significant construction aggregate resources. This adjacent area supplies Ventura County and surrounding production - consumption regions with aggregate materials and is permitted to do so for the next 50 years. The 2011 EIR concluded that the potential loss of known mineral resources at the Project Site would result in a less than significant impact.
Oil deposits, along with the possible presence of natural gas, are known to exist in the northern part of the City, including areas adjacent to and within the Project Site. At the time of the 2011 EIR, 51 oil wells were located within the Project Site, spe cifically in the Tapo Canyon portion. No wells were present in the Dry Canyon portion. Most of the wells were designated as idle or plugged, with the operators listed as inactive. Of the 51 wells, one—Tapo Canyon Well No. 35 -1, owned by Seneca Resources Co rporation—was designated as idle, while the remaining wells were reported as plugged and abandoned. Well No. 35-1 is temporarily abandoned and plugged, allowing the operator to potentially reopen it for oil extraction. In its current state, the well does n ot pose health, safety, aesthetic, or noise-related concerns. However, if reactivated, it could result in impacts similar to those associated with future wells.
The 2011 EIR disclosed that due to the presence of mineral resources and an existing well on the Project Site, the Approved Project included reduced minimum setback distances for active wells near residential units. The proposed and approved 50 -foot setback from a drill site, combined with state regulations prohibiting active wells within 100 feet of the outer boundary of the parcel, results in a total setback of 150 feet. This distance is less than the City’s Development Code requirement, which prohibits wells within 800 feet of any building or dwelling not necessary for well operations. Therefore, the Approved Project was found to be inconsistent with this provision of the Development Code.
To mitigate potential impacts from proximity to residential land uses, the 2011 EIR required implementation of mitigation measures 4.9-1 through 4.9-4:
• Mitigation Measure 4.9 -1: If operating wells are located in areas planned for residential development, the Approved Project must install walls, fencing, and equipment screening to obscure unsightly conditions. These features must conform to Specific Plan standards and be shown on an exhibit submitted with the tract map.
The Environmental Services Director must review and approve the location and design.
• Mitigation Measure 4.9 -2: Prior to tract map approval for areas containing existing drill sites, the applicant must submit a completed Well Review Program request to DOGGR and take additional required steps.
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ADDENDUM NO. 1 TO THE EIR
• Mitigation Measure 4.9 -3: For tract maps that include or are adjacent to Well No. 35-1, the applicant must comply with DOGGR’s setback requirements to maintain rig access and avoid construction over or near the well. • Mitigation Measure 4.9-4: No dwelling unit may be constructed within 300 feet of an active or temporarily abandoned well unless DOGGR designates the well as “critical.” In all cases, habitable structures must be at least 150 feet from any active or temporarily abandoned well.
With implementation of mitigation measures 4.9-1 through 4.9-4, the 2011 EIR determined that the Approved Project would result in less than significant impacts related to mineral resources.
Mitigation Program
• 4.9-1. Should operating wells be located in areas where residential development is planned, the project shall install walls and fencing, and utility and equipment screening to block or obstruct unsightly conditions that distract from the neighborhood street scene. The location of such walls, fencing or other screens shall be in conformance with the standards set forth in the Specific Plan and shall be shown on an appropriate exhibit at the time of tract map submittal. The location and design of such walls, fencing and/or screening shall be reviewed and approved by the Director of Environmental Services.
• 4.9-2. Prior to approval of tract maps for areas that include existing drill site locations, the applicant shall submit to DOGGR:
o a fully completed Well Review Program Application,
o locate all known wells located on the development site property, o a preliminary copy of the development site plan to the DOGGR for review. The plan needs to show, at a minimum, the boundary of the development site property with all known wells plotted on the property, final grade of the development site property, and a visual bar scale.
After the DOGGR has conducted a review and evaluation of all known wells located on the development site property, and the well sites have been restored, DOGGR will issue a Well Review Letter to the applicant and the local permitting agency. • 4.9-3. Prior to approval of tract maps that include or are adjacent to well No. 35-1, the applicant shall provide for the setback requirements pursuant to DOGGR’s Well Review Program for: 1) maintaining rig access to the well, and 2) not building over, or in close proximity to the well
• 4.9.4. The applicant shall not construct any dwelling unit within 300-feet of an active or temporarily abandoned well unless such well is designated by the DOGGR as a “critical well.” In no case shall any habitable structure be built within 150 feet of any active or temporarily abandoned well.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-102
ADDENDUM NO. 1 TO THE EIR
3.11.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
MINERAL RESOURCES – Would the project:
a) Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state?
b) Result in the loss of availability of a locally -important mineral resource recovery site delineated on a local general plan, specific plan or other land use plan?
Would the Project:
a) Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state? and
b) Result in the loss of availability of a locally-important mineral resource recovery site delineated on a local general plan, specific plan or other land use plan? No Substantial Change from Previous Analysis . As disclosed in the 2011 EIR for the Approved Project, the Proposed Project would result in loss of availability of mineral resources that are known to occur in the Project Site. However, the Proposed Project would reduce the overall impact footprint of the project so impacts would be reduced related to surface mineral resource availability.
Also, the Proposed Project would reduce opportunities for oil well drilling in the Project Site given the Proposed Project would develop new residential land uses in the Project Site and because setbacks are required from wells for residential land uses.
As with the Approved Project, the Proposed Project would not result in any direct effects to the site that is identified as a “ locally important construction aggregate quarry ” that is located immediately north of the Project Site (e.g., Gillibrand Industrial Sands).
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to mineral resources that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to mineral resources continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-103
ADDENDUM NO. 1 TO THE EIR
3.12 NOISE
3.12.1 2011 EIR
Noise Impact Analysis
The 2011 Environmental Impact Report (EIR) evaluated potential noise impacts from roadway sources, stationary sources, and construction activities associated with the Approved Project’s residential uses. It disclosed that vehicular noise could affect sensitive receptors both within the Project Site and along the surrounding roadway network.
Anticipated noise increases ranged from 0.0 dB(A) at several road segments (e.g., Erringer Road south of SR -118 eastbound Ramps, Avenida Simi, Sycamore Drive, and Tapo C anyon Road) to a maximum of 5.0 dB(A) along Lost Canyons Drive between Lost Canyons Golf Club and Tapo Canyon Road. Although a 5.0 dB(A) increase is typically considered significant, this segment was not adjacent to sensitive receptors at the time of analy sis. Internal roadway noise was modeled to remain below the City of Simi Valley’s 63.0 dB(A) CNEL threshold, resulting in a determination of less -than-significant impacts for both on -site and off -site roadway noise.
Oil Well Noise Impacts
Active oil wells were required to maintain a 150-foot setback from residential dwellings (100 feet per DOC requirements and 50 feet per the proposed Specific Plan). However, noise levels from drilling and well field equipment were projected to range from 5 9.8 to 77.8 dB(A) at 150 feet, exceeding thresholds for residential outdoor and indoor areas —even with attenuation of 17.0 to 25.0 dB(A). These impacts were deemed potentially significant depending on proximity to residential units.
To address this, mitigation measure 4.10 mandates a noise study prior to tract map approval in areas with active wells. If the study finds that noise thresholds would be exceeded, applicants must construct appropriate noise attenuation features (e.g., wall s) before occupancy permits are issued, following Specific Plan guidelines.
Oil well operators must obtain a Conditional Use Permit (CUP), allowing the City to assess site conditions and proximity to sensitive uses. If the Specific Plan amendment is approved, applicants may be required to implement additional mitigation and best m anagement practices (BMPs). For wells within 1,600 feet of residences, the Development Code mandates noise mitigation. With these measures, future oil well operations are expected to result in less-than-significant noise impacts.
One capped oil well, Tapo Canyon Well No. 35-1 (API No. 11121637), is located on the Project Site and may resume operation pending CUP approval. Any future operations at this or other drill sites must comply with the mitigation requirements, ensuring noise impacts remain less than significant.
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LOST CANYONS SPECIFIC PLAN PROJECT 3-104
ADDENDUM NO. 1 TO THE EIR
Construction Noise and Vibration
Construction activities—including grading, building, and infrastructure development—were expected to generate temporary noise and vibration. Equipment such as tractors, loaders, mixers, and cranes could intermittently expose nearby residences (especially a long the western, southwestern, and southeastern boundaries) to noise increases exceeding 5 dB(A) and vibration levels ranging from 0.003 to 0.089 in/sec. To mitigate these impacts, the following measures were required:
As required by mitigation measure 4.10-2, the construction contractors during grading and earthmoving activities shall adjust vibration amplitudes of the construction equipment on the Project Site, such as by limiting the number of pieces concurrently oper ating in one location in areas where conditions would affect structures, sensitivity of vibration equipment, and/or human tolerance.
Related to temporary noise increases during construction, mitigation measure 4.10-3 would be implemented, which requires that the applicant shall limit all site demolition, preparation, and construction activities to between the hours of 7:00 AM to 7:00 PM seven days a week (Section 5 -16.02(i)). Furthermore, construction equipment maintenance, diesel engine start-ups, the positioning, and movement of equipment, and similar preconstruction staging activities shall be limited to the same hours. Non -noise-generating construction activities such as interior painting shall not be subject to these restrictions. The City of Simi Valley building official or a designee shall spot check and respond to complaints.
As required by mitigation measure 4.10-4, t he applicant, as feasible, shall supply all construction equipment with improved noise muffling, and have the manufacturers’ recommended noise -abatement measures, such as mufflers, engine covers, and engine vibration isolators in good working condition.
As required by mitigation measure 4.10-5, t he applicant, as feasible, shall use hydraulic equipment instead of pneumatic impact tools and electric -powered equipment instead of diesel-powered equipment for all exterior construction work, unless the use of pneumatic impact tools and diesel powered eq uipment is specifically approved by the Deputy Director/City Planner. If use of these tools and equipment are allowed, the applicant shall specify the dates and times of use and shall notify the Deputy Director/Ci ty Planner when work involving this equipment is to take place.
As required by mitigation measure 4.10-6, the applicant shall turn off all equipment, such as construction equipment including heavy -duty equipment, motor vehicles, and portable equipment, if not in use.
As required by mitigation measure 4.10-7, t he applicant shall require by contract specifications that the following construction best management practices (BMPs) be implemented by the contractor to reduce construction noise levels:
• Two weeks prior to the commencement of construction, notification disclosing the construction schedule, including various types of activities that would be occurring throughout the duration of the construction period, must be provided to surrounding 1069
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LOST CANYONS SPECIFIC PLAN PROJECT 3-105
ADDENDUM NO. 1 TO THE EIR
land uses (specifically the existing residential communities located along the western, southwestern and southeastern boundary of the proposed project) within 1,500 feet of the project site.
• Ensure that construction equipment is properly muffled according to industry standards and is in good working condition to reduce excess noise levels. • Place noise-generating construction equipment and locate construction staging areas away from the sensitive uses (existing residential communities surrounding the proposed project) where feasible.
• As feasible, schedule high -noise-producing activities between the hours of 8:00 AM and 5:00 PM to minimize disruption to sensitive uses (existing residential communities surrounding the proposed project).
• Implement noise-attenuation measures to the extent feasible, which may include, but are not limited to, temporary noise barriers or noise blankets around stationary construction noise sources.
• Use electric air compressors and similar power tools rather than diesel equipment where feasible.
• Construction hours, allowable workdays, and the phone number of the job superintendent shall be clearly posted at all construction entrances within the proposed project site to allow for surrounding residents and property owners to contact the job superint endent. If the City of Simi Valley or the job superintendent receives a complaint, the superintendent shall investigate, take appropriate corrective action, and report the action taken to the reporting party. Contract specifications shall be included in th e proposed project construction documents, which shall be reviewed by the City of Simi Valley prior to the issuance of a grading permit.
As required by mitigation measure 4.10-8, t he applicant shall require by contract specifications that staging areas along with the operation of earthmoving and grading equipment within the proposed project areas be located as far away from vibration - and noise-sensitive sites (residential communities located along the western, southwestern, and southeastern boundary of the proposed project site) as possible and where feasible.
As required by mitigation measure 4.10-9, the applicant shall require by contract specifications that heavily loaded trucks used during construction be routed away from existing residential streets and restricted to using Tapo Canyon Road and Lost Canyons Drive to access development areas within the proposed project site.
Mitigation Program
• 4.10-1. Prior to the approval of tract maps, in areas of existing active wells, the applicant shall conduct and submit to the Director of Environmental Services for review and approval, a noise study to determine whether noise attenuation features, such as walls, are required to reduce noise from existing oil wells to meet the City’s thresholds. If the study determines that the proposed residential units will not meet 1070
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ADDENDUM NO. 1 TO THE EIR
the noise requirements of the City, then the applicant shall provide for and construct, prior to issuance of occupancy permits, appropriate noise walls, pursuant to the guidelines for Walls and Fences provided in the proposed Specific Plan to reduce noise to existing levels.
• 4.10-2. The construction contractors during grading and earthmoving activities shall adjust vibration amplitudes of the construction equipment on site, such as by limiting the number of pieces concurrently operating in one location in areas where conditions would affect structures, sensitivity of vibration equipment, and/or human tolerance.
• 4.10-3. The applicant shall limit all site demolition, preparation, and construction activities to between the hours of 7:00 AM to 7:00 PM seven days a week (Section 5 -
16.02(i)). Furthermore, construction equipment maintenance, diesel engine start - ups, the positioning, and movement of equipment, and similar preconstruction staging activities shall be limited to the same hours. Non -noise-generating construction activities such as interior painting shall not be subject to these restrictions. The City of Simi Valley building official or a designee shall spot check and respond to complaints.
• 4.10-4. The applicant, as feasible, shall supply all construction equipment with improved noise muffling, and have the manufacturers’ recommended noise - abatement measures, such as mufflers, engine covers, and engine vibration isolators in good working condition.
• 4.10-5. The applicant, as feasible, shall use hydraulic equipment instead of pneumatic impact tools and electric -powered equipment instead of diesel -powered equipment for all exterior construction work, unless the use of pneumatic impact tools and diesel powered equipment is specifically approved by the Deputy Director/City Planner. If use of these tools and equipment are allowed, the applicant shall specify the dates and times of use and shall notify the Deputy Director/City Planner when work involving this equipment is to take place.
• 4.10-6. The applicant shall turn off all equipment, such as construction equipment including heavy-duty equipment, motor vehicles, and portable equipment, if not in use.
• 4.10-7. The project applicant shall require by contract specifications that the following construction best management practices (BMPs) be implemented by the contractor to reduce construction noise levels:
o Two weeks prior to the commencement of construction, notification disclosing the construction schedule, including various types of activities that would be occurring throughout the duration of the construction period, must be provided to surrounding land u ses (specifically the existing residential communities located along the western, southwestern and southeastern boundary of the Project Site) within 1,500 feet of the Project Site. o Ensure that construction equipment is properly muffled according to industry standards and is in good working condition to reduce excess noise levels. 1071
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ADDENDUM NO. 1 TO THE EIR
o Place noise -generating construction equipment and locate construction staging areas away from the sensitive uses (existing residential communities surrounding the Project Site) where feasible.
o As feasible, schedule high -noise-producing activities between the hours of 8:00 AM and 5:00 PM to minimize disruption to sensitive uses (existing residential communities surrounding the Project Site).
o Implement noise -attenuation measures to the extent feasible, which may include, but are not limited to, temporary noise barriers or noise blankets around stationary construction noise sources.
o Use electric air compressors and similar power tools rather than diesel equipment where feasible
o Construction hours, allowable workdays, and the phone number of the job superintendent shall be clearly posted at all construction entrances within the Project Site to allow for surrounding residents and property owners to contact the job superintendent. If the City of Simi Valley or the job superintendent receives a complaint, the superintendent shall investigate, take appropriate corrective action, and report the action taken to the reporting party. Contract specifications shall be included in the project construction documents, which shall be reviewed by the City of Simi Valley prior to the issuance of a grading permit.
• 4.10-8. The project applicant shall require by contract specifications that staging areas along with the operation of earthmoving and grading equipment within the Project Site be located as far away from vibration - and noise -sensitive sites (residential communities located along the western, southwestern, and southeastern boundary of the Project Site) as possible and where feasible. • 4.10-9. The project applicant shall require by contract specifications that heavily loaded trucks used during construction be routed away from existing residential streets to the extent feasible by primarily and restricted to using Tapo Canyon Road and Lost Canyons Drive to access development areas within the Project Site 1072
Environmental Checklist
LOST CANYONS SPECIFIC PLAN PROJECT 3-108
ADDENDUM NO. 1 TO THE EIR
3.12.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
NOISE – Would the project result in:
a) Generation of a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies?
b) Generation of excessive groundborne vibration or groundborne noise levels?
c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels?
The responses in this section are based on a Noise and Vibration Assessment Technical Memorandum that was prepared for the Proposed Project by Michael Baker International in February 2025 (Michael Baker International 2025d).
Would the Project:
a) Generation of a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? No Substantial Change from Previous Analysis. As detailed in the 2011 EIR, construction of the Approved Project would result in construction noise associated with the use of heavy equipment, such as tractors, loaders, concrete mixers, and cranes in the Project Site. The Proposed Project would result in a similar amount of construction activity within the same footprint as would the Approved Project. Consistent with the findings of the 2011 EIR for the Approved Project, c onstruction activities for the Propos ed Project would also occasionally and intermittently expose the existing residential uses along the western, southwestern, and southeastern boundaries of the Project Site to noise levels of more than 5 dBA over existing conditions. However, demolition, grading, and construction activities would be limited to the hours of 7:00 AM to 7:00 PM. Additionally, any demolition, grading, and construction activities would be short -term and intermittent. As such, consistent with the finding in t he 2011 EIR, the Proposed Project would be required to implement mitigation measure 4.10-3 through mitigation measure 4.10-9, which would reduce the Proposed Project’s construction noise impacts to a less than significant level.
As detailed in the 2011 EIR , vehicular noise could potentially affect sensitive receptors within the approved project area, as well as sensitive receptors located along the surrounding roadway system. Noise increases resulting from the development of the 1073
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ADDENDUM NO. 1 TO THE EIR
approved project range from a low of 0.0 dB(A) (Erringer Road south of SR -118 eastbound Ramps, Avenida Simi between Anderson Drive and Sycamore Drive, Sycamore Drive south of SR-118 eastbound Ramp, and Tapo Canyon Road south of SR-118 eastbound Ramps) to a high of 5.0 dBA (Lost Canyons Drive between Lost Canyons Golf Club and Tapo Canyon Road). An increase in noise levels of 5.0 dBA or more is typically considered significant and can impact sensitive receptors. However, the location of the road segment betw een Lost Canyon Golf Club (Driveway) to Tapo Canyon Road along Lost Canyons Drive is not adjacent to sensitive receptors. Modeling results of the future noise level, which the internal circulation road system within the approved project is expected to crea te, would be below the City of Simi Valley’s standard of 63.0 dBA CNEL. As such, impacts associated with the internal roadway system of the Approved Project was determined in the 2011 EIR to be less than significant. Therefore, the 2011 EIR determined that impacts associated with on -site and off-site roadway noise would be less than significant.
Regarding point source noise, the 2011 EIR noted that future residents of the Approved Project would generate and be exposed to point source noise, including people talking, doors slamming, street cleaning, air conditioning units, lawn care equipment, stereos, and domestic animals. Given that the Proposed Project would include similar land uses, the Proposed Project would also result in these same noise effects. These noise sources would contribute to the ambient noise levels experienced in all similarly de veloped areas (e.g., those residential areas existing south of the Project Site) and typically do not exceed noise standards for the types of land uses proposed. As a result, consistent with the determination in the 2011 EIR, the Proposed Project would result in less than significant impacts related to potential point source noise impacts.
Also, the Proposed Project would be required to implement mitigation measures from the 2011 EIR including mitigation measure 4.10-1 and mitigation measure 4.10- 3, to address potential noise impacts to residential development adjacent to existing or future oil wells.
Short-Term Construction Noise Impacts
As with the Approved Project, the Proposed Project would result in short-term construction noise impacts. Noise from construction activities is generated by two primary sources: (1) the transport of workers and equipment/materials to construction sites and (2) the noise related to active construction equipment. These noise sources can be a nuisance to local residents an d businesses or, in some cases, unbearable to sensitive receptors (i.e., residences, hospitals, senior centers, schools, day care facilities, etc.).
Construction noise levels in the vicinity of the Proposed Project’s construction activities would fluctuate depending on the type, number, and duration of usage for the varying equipment in operation at any one given time . The effects of construction noise largely depend on the type of construction activities occurring on any given day, noise levels generated by those activities, distances to noise -sensitive receptors, and the existing ambient noise environment in the rece ptor’s vicinity. Construction gener ally occurs in several discrete phases, with each phase requiring different equipment with varying noise characteristics. These phases alter the characteristics of the noise environment generated on the Project Site and in the surrounding community for the duration of the construction process.
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ADDENDUM NO. 1 TO THE EIR
Construction of the Proposed Project is anticipated to occur in two phases. Phase 1 would include construction of 180 residential lots in the eastern, southern, and western portions of the Project Site and would consist of the following activities: demolition, grading, building construction, paving, and architectural coating. Phase 2 of the Proposed Project in the northern portion of the Project Site would include grading, building construction, paving, and architectural coating. The Proposed Project would require the demolition of approximately 31,300 square feet of vacant structures associated with the former gold course facilities in the Project Site.
Noise levels from construction equipment and activities were modeled for the Proposed Project as a part of the Noise and Vibration Assessment Technical Memorandum using the Federal Highway Administration’s RCNM. The estimated construction noise levels for the Proposed Project at the nearest noise -sensitive receptors were calculated and were presented in the Noise and Vibration Assessment Technical Memorandum.
The closest sensitive receptors to the Proposed Project’s construction activities that could experience some noise and vibration due to the construction and development of the Proposed Project are the residential areas, known as the Glenmeadow neighborhood, located at the western edge of the Project Site, approximately 150 feet from the edge of the Proposed Project’s impact footprint.
As shown in the Noise and Vibration Assessment Technical Memorandum , the nearest receptors to the Lost Canyons Project site could be exposed to temporary and intermittent construction noise levels during overlapping construction activities ranging from approximately 43.5 to 56.2 dBA Leq at the nearest residential use to t he west. As such, construction noise would not have the potential to exceed the City’s exterior land use compatibility standard of 63.0 dBA Leq by 10.0 dBA or more at the nearest sensitive receptors. It should be noted that the Proposed Project’s potential construction impact on Phase 1 developments is not analyzed, as according to the construction schedule provided by the applicant, Phase 1 construction activities would not be completed and residential units would not be occupied when Phase 2 construction activities are occurring.
To further minimize impacts, the Proposed Project would be required to comply with mitigation measure 4.10 -3 through mitigation measure 4.10-9 from the 2011 EIR . These mitigation measures lay out the required steps required to comply with the City’s construction hours limitation as well as other best management practices regarding construction noise reduction that must be implemented during construction of the Proposed Project. In addition, it is acknowledged that according to the Simi Valley Municipal Code Section 5-16.02 (i), construction activities occurring between the hours of 7:00 AM and 7:00 PM, except when the urgent necessity, would not be declared to be nuisances by the City. The Proposed Project’s construction activities would occur within the allowable hours specified by Simi Valley Municipal Code unless the City Engineer determines that limiting construction to these hours would create a health or safety issue or a substantial loss or inconvenience as described in the Simi Valley Municipal Code . Any demolition, grading, and construction activities would be short-term and intermittent and would be required to abide by the Simi Valley Municipal Code Noise Regulations. As such, the Proposed Project would result in less than significant impacts related to construction noise, which is similar to the finding in the 2011 EIR for the Approved Project.
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ADDENDUM NO. 1 TO THE EIR
Long-Term Operational Noise Impacts
Off-Site Mobile Noise
The Proposed Project’s Noise and Vibration Assessment Technical Memorandum evaluated roadway segment noise levels for the “Existing” and “Existing with Project” scenarios to evaluate operational mobile noise impacts that would result from the Proposed Project .
According to the Noise and Vibration Assessment Technical Memorandum , under the “Existing” scenario, noise levels at 100 feet from the roadway centerline would range from
51.6 dBA to 68.8 dBA CNEL with implementation of the Proposed Project. Existing baseline traffic noise levels would be greater than 63 dBA CNEL at Erringer Road between Simi Town Center Way and SR-118 EB Ramps, Erringer Road South of SR-118 EB Ramps, Tapo Canyon Road between Lost Canyons Drive and Alamo Street, Tapo Canyon Road betwee n Alamo Street and SR-118 WB Ramps, Tapo Canyon Road between SR -118 WB Ramps and SR -118 EB Ramps, and Tapo Canyon Road South of SR-118 EB Ramps The Proposed Project would generate approximately 3,483 trips per day without taking any credits from the existing use. Under the “Existing with Project” scenario, noise levels at 100 feet from the roadway centerline would range from 53.6 dBA to 68.8 dBA CNEL according to the Noise and Vibration Assessment Technical Memorandum . As shown in the Noise and Vibration Assessment Technical Memorandum, the Proposed Project would result in an increase in noise levels between the two scenarios from between 0.0 dBA to 3.2 dBA CNEL increases.
As shown in the Noise and Vibration Assessment Technical Memorandum , change in noise levels between the “Existing” scenario and the “Existing With Project” scenario would be less than 3 dBA for all roadway segments except for the Lost Canyons Drive (between Erringer Road and Lost Canyons Golf Club) segment. Further, “Existing With Project” traffic noise levels would remain below the City’s land use compatibility standards of 63 dBA CNEL at this roadway segment with implementation of the Proposed Project acc ording to the Noise and Vibration Assessment Technical Memorandum.
According to the Noise and Vibration Assessment Technical Memorandum, the Proposed Project would result in a significant noise impact if a permanent increase in ambient traffic noise levels of 3.0 dB occurs upon project implementation and the resulting noise level at the receiving sensitive receptor were to exceed the applicable exterior standard at a noise sensitive use.
As outlined in the Noise and Vibration Assessment Technical Memorandum , the Proposed Project would not result in this large of an increase in noise levels.
Cumulative Traffic Noise
In the Noise and Vibration Assessment Technical Memorandum, the “Future Without Project” and “Future With Project” scenarios were compared for the Proposed Project to evaluate long-term mobile source project noise impacts. 1076
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As detailed in the Noise and Vibration Assessment Technical Memorandum , traffic noise levels under the “Future Without Project” scenario would range from 58.2 dBA to 69.7 dBA CNEL. Under the “Future With Project” scenario, which would be with implementation of the Proposed Project, noise levels would range from 58.7 dBA to 69.8 dBA CNEL. Further, the increase in ambient noise between the two scenarios would range from 0.0 dBA to 0.9 dBA CNEL according to the Noise and Vibration Assessment Technical Memorand um. Based on applicable criteria, the Proposed Project would result in a significant noise impact if a permanent increase in ambient traffic noise levels of 3.0 dB were to occur upon implementation of the Proposed Project and the resulting noise level at the receiving sensitive receptor were to exceed the applicable exterior standard at that particular noise sensitive use.
As outlined in the Noise and Vibration Assessment Technical Memorandum , the Proposed Project would not result in this large of an increase in noise levels.
On-Site Operational Noise
Mechanical Equipment
As described in the Proposed Project’s Noise and Vibration Assessment Technical Memorandum, noise from heating, ventilation, and air conditioning (HVAC) units would result from the Proposed Project, similar to what was anticipated in the 2011 EIR for the Approved Project . Typically, mechanical equipment, such as HVAC units, generate noise levels of 60 dBA at 20 feet from the source. Noise generated by stationary sources typically attenuates at a rate of 6 dBA per doubling of distance from the source. The nearest sensitive receptors to the Proposed Project’s construction activities are the residential areas, known as the Glenmeadow neighborhood, located at the western edge of the Project Site. Measured from the nearest residence to a HVAC unit on the nearest proposed dwelling unit, the distance is approximately 800 feet. At the distance of 800 feet, noise levels from HVAC units would be approximately 28 dBA. As such, operation of the HVAC units would n ot have the potential to exceed the City’s exterior land use compatibility standard for residential uses of
63.0 dBA Leq or the existing ambient noise of 60.6 dBA Leq at the nearest sensitive receptors.
As a result, the Noise and Vibration Assessment Techn ical Memorandum determined that the Proposed Project would result in a less than si gnificant impact related to operational mechanical noise.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Generation of excessive groundborne vibration or groundborne noise levels? No Substantial Change from Previous Analysis. Similar to the Approved Project, the Proposed Project would result in construction activities that could lead to groundborne vibration and groundborne noise levels becoming excessive. 1077
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As described in the Noise and Vibration Assessment Technical Memorandum, the Proposed Project’s demolition, grading, and construction activities would be limited to the hours of 7:00 AM to 7:00 PM. Additionally, any demolition, grading, and construction activities would be short-term and intermittent. As such, consistent with the findings in the 2011 EIR for the Approved Project, the Proposed Project was found to require implementation of mitigation.
As required in the 2011 EIR , the Proposed Project would i mplement m itigation measure
4.10-2, which require s that the construction contractors for the Proposed Project adjust vibration amplitudes of the construction equipment on -site such as by limiting the number of pieces concurrently operating in one location in areas where conditions would affect structures, sensitivity of vibration equipment, and/or human tolerance , vibration impacts would be reduced to less than significant levels.
The Noise and Vibration Assessment Technical Memorandum evaluated s hort-term construction vibration impacts for the Proposed Project , which determined that the Proposed Project’s construction would generate varying degrees of groundborne vibration, depending on the construction procedure and the construction equipment used. Operation of construction equipment would generate vibrations that would spread through the ground and that would diminish in amplitude with distance from the source. The effect on buildings located in the vicinity of the construction site would vary depending on soil type, ground strata, and construction characteristics of the receiver building(s). The results from vibration can range from no perceptible effects at the lowest vibration levels, to low rumbling sounds and perceptible vibration at moder ate levels, to slight damage at the highest levels. Groundborne vibrations from construction activities rarely reach levels that damage structures. The Caltrans Transportation and Construction Vibration Manual identifies various vibration damage criteria for different building classes. The evaluation of the Proposed Project contained in the Noise and Vibration Assessment Technical Memorandum uses the Caltrans architectural damage criterion for vibrations from continuous/frequent intermittent sources at new residential and commercial structure buildings of 0.5 inch -per-second (inch/second) PPV . The highest degree of groundborne vibration would be generated due to the operation of vibratory rollers during the paving phase as detailed in the Noise and Vibration Assessment Technical Memorandum . As previously mentioned, the nearest sensitive receptors are the residential areas, known as the Glenmeadow neighborhood, located at the western edge of the edge of the development at approximately 150 feet from the closest project boundary. Vibration from construction equipment is calculated at 150 feet to evaluate the architectural building damage criterion.
Typical vibration produced by construction equipment is illustrated in the Noise and Vibration Assessment Technical Memorandum.
As indicated in the Noise and Vibration Assessment Technical Memorandum , the reference vibration velocities from typical heavy construction equipment operation would range from
0.003 to 0.210 inch/second PPV at 25 feet (reference) from the source of activity. At 150 feet, vibration velocities from typical heavy construction e quipment, including vibratory rollers, would range from 0.002 to 0.0143 inch/second PPV which would not exceed Caltrans architectural damage criterion of 0.5 inch/second PPV as detailed in the Proposed Project’s Noise and Vibration Assessment Technical Memorandum . As a result, construction groundborne vibration from the Proposed Project would not be capable of exceeding the 0.5 inch/second PPV significance threshold for vibration to the nearest structures and so the Proposed Project would result in a less than significant impact related to this topic. 1078
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Long-Term Operational Vibration Impacts
As described in the Proposed Project’s Noise and Vibration Assessment Technical Memorandum, similar to the Approved Project, the Proposed Project would not involve any operational activities that would generate groundborne vibration. The project operation would not involve railroad operation and therefore would not result in vibration impacts at surrounding uses. Thus, no impacts would occur in this regard (Michael Baker International 2025d).
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the Project expose people residing or working in the project area to excessive noise levels?
No Substantial Change from Previous Analysis. According to the 2011 EIR, the Approved Project is not located within the boundaries of any airport land use compatibility plans or within 2 miles of an airport or airstrip. Also, t he Project Site is not located within the boundaries of any airport land use compatibility plans or within 2 miles of an airport or airstrip. Additionally, the project site is not located within the vicinity of a private airstrip or related facilities. There have been no new airports developed since the 2011 EIR was certified. As such, the Proposed Project would be no impact related to this threshold.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to noise that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to noise continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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ADDENDUM NO. 1 TO THE EIR
3.13 POPULATION AND HOUSING
3.13.1 2011 EIR
The 2011 EIR described that the population of the City of Simi Valley was estimated by the California Department of Finance (DOF) to be 125,657 at the time of the preparation of the 2011 EIR . According to the City of Simi Valley Managed -Growth Plan, the maximum population projection for 2010 was expected to increase to 131,205 and to 135,828 for 2015.
Based on the Managed-Growth Plan the average household size in the City is 3.157 persons; therefore, the 364 dwelling units generated by the Approved Project would translate into a population increase of 1,149 residents as described in the 2011 EIR. Overall, the increase in population due to the Approved Project would equal approximately 0.9 percent of the City’s 2008 population and about 0.8 percent of the City’s projected 2015 population. While the Approved Project would account for some of the projected growth within the City, on a project-specific basis it would not result in population increases that exceed City projections.
As such, the 2011 EIR found that the Approved Project would not result in significant population impacts.
The 2011 EIR disclosed that the Approved Project’s 364 additional residential units would have direct impacts to the housing inventory, which would result in an increase in the availability of market-rate housing opportunities in the City. Based on the City’s maximum allocation of 73 allocation grants, or equivalent dwelling units, per quarter per calendar year the projected housing growth within the City of Simi Valley between 2010 and 2015 is estimated to be about 1,168 dwelling units. T he 2011 EIR descri bed that the 364 dwelling units proposed by the Approved Project would equal about 31 percent of the units projected to be developed within the City between 2010 and 2015, and would not result in City projections being exceeded. Therefore, the 2011 EIR determined that the Approved P roject would not result in significant impacts related to housing and that no mitigation measures were not required.
Mitigation Program
The 2011 EIR did not include mitigation measures directly related to population and housing.
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3.13.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
POPULATION AND HOUSING–Would the project:
a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)?
b) Displace substantial number of existing people or housing, necessitating the construction of replacement housing
elsewhere?
Would the Project:
a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would result in an additional 364 residential units within the Project Site .
Using an average household size for Simi Valley of 2.8 persons per household, 364 new residential units would result in approximately 1,020 new residents, which is similar to the number of new residents anticipated in the 2011 EIR (US Census Bureau 2025).
Since the 2011 EIR was certified, Senate Bill 330 (SB 330) was passed in 2019 establishing the Housing Crisis Act (HCA), which was signed on October 9, 2019 and went into effect on January 1, 2020. On September 16, 2021, Senate Bill 8 (SB 8) was signed into law which made some clarifications and updated SB 330, extending the HCA from January 1, 2025 to January 1, 2030. Subsequently, in 2025, AB 130 was passed which amends the Housing Crisis Act to remove sunset dates that were imposed as a part of SB 330 making this law now permanent unless it is repealed. These laws were passed to address the current “housing crisis” in the State with three general aims: 1) increase residential unit development; 2) protect existing housing inventory; and 3) expedite permit processing. SB 330 , SB 8 , and AB 130 make numerous changes to the existing legislation such as the Permit Streamlining Act and the Housing Accountability Act to increase the production of housing units in California . The Proposed Project would include 364 residential units, which would achieve state and local goals and policies for housing production.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?
No Substantial Change from Previous Analysis. The Proposed Project would not result in the displacement of any existing housing units or residents from within the Project Site.
As such, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to population and housing that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project.
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3.14 PUBLIC SERVICES
3.14.1 2011 EIR
Fire Services
Fire protection services would be provided to the Approved Project by the Ventura County Fire Protection District (VCFPD), under contract with the City of Simi Valley. The 2011 EIR determined that the VCFPD’s resources are adequate to serve the Approved Project , and response times to service calls at the Project Site would meet VCFPD’s standards.
The 2011 EIR disclosed that the Project Site is located near areas designated by the state as very high fire hazard, and by the VCFPD as high fire hazard areas.
The 2011 EIR disclosed that the Approved Project would result in risks of wildfire ignition during construction related to c onstruction equipment that may emit sparks that would present a fire risk of, especially during site clearance.
The 2011 EIR disclosed that construction of the Approved Project would increase traffic both on and adjacent to the Project Site during working hours because commuting construction workers, trucks, and other construction vehicles would be added to normal traffic during buildout of the project. The 2011 EIR disclosed that the additional traffic could slow emergency response and evacuations if they needed to occur during construction of the Approved Project. However, the 2011 EIR determined that with a dherence to existing City codes and requirements during construction, the Approved Project would result in less than significant impacts related to fire hazards.
The 2011 EIR disclosed that fire stations in the vicinity of the Project Site had capacity to serve the Approved Project, and the water supply was adequate to support firefighting requirements for the Approved Project. As discussed in the 2011 EIR, t he Approved Project would be expected to require a minimum fire flow of 1,000 gallons per minute (gpm) for a 2-hour duration to provide sufficient water to fire fighters during an emergency, which can be provided by existing water tanks in the area in conjunction with the ne w water tank proposed for the northeastern portion of the Project Site.
The 2011 EIR specified that the Approved Project must implement mitigation measures 4 - 12-1 through and 4.12-10.
As response times and fire flows will meet VCFPD’s service standards with implementation of the Approved Project , impacts related to fire services for the Approved Project were determined in the 2011 EIR to be less than significant.
Police Services
The 2011 EIR identified minor impacts to police services that would result from the construction of the Approved Project. Site development and construction would not normally require services from the police department, except in the cases of trespassing, 1083
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theft, or vandalism. Such activities at a construction site are usual, and do not typically place undue demands on law enforcement services. Slow -moving, construction -related traffic along local roadways may reduce optimal traffic flows and would conceivab ly delay emergency vehicles or contribute to a vehicle accident. However, the 2011 EIR determined this to be a less than significant impact given the periodic and temporary nature of construction-related traffic. Implementation of standard construction tra ffic control procedures—such as the use of flagmen and signage showing traffic detour plans, haul routes, hours of operation, protective devices, warning signs, and access to abutting properties—would further reduce any potential impact to less than significant.
The 2011 EIR disclosed that the City’s Municipal Code establishes fees for residential development that are to be used for the maintenance of City roads and for the provision of law enforcement services. The 2011 EIR found that the Approved Project would result in the development of 364 residential units and the addition of an estimated 1,149 residents to the City’s population that would need police services.
To reduce impacts related to police services, mitigation measure s 4.13 -1 through 4.13 -5 would be implemented as a part of the Approved Project.
As required by mitigation measure 4.13-1, prior to the issuance of building permits, prior to final plan approval, the developer of the project shall pay the City's police facilities fee that is required of all new developments to defray the cost of providing increased levels of police protection.
As required by mitigation measure 4.13-2, prior to issuance of building permits, the City shall review development plans for the incorporation of defensible space concepts to reduce demands on police services. To the degree feasible, public safety planning recommendations shall be incorporated into the project plans.
As required by mitigation measure 4.13-3, where feasible, open spaces shall be designed to facilitate easy viewing from patrol cars and by citizens on adjacent streets. To the extent possible—and without destroying the character —access streets and trails shall be incorporated into open spaces for occasional patrols and other emergency vehicles.
As required by mitigation measure 4.13-4, t he Approved Project would be required to implement security recommendations during construction and operation regarding site security, lighting, landscaping, building access and visibility, street circulation, building design, and defensible space, which are identified in th e form of planning department conditions. These would be identified by the police department during the tentative tract map and residential planned development reviews.
As required by mitigation measure 4.13-5, t o reduce emergency vehicle delays during construction, the applicant shall implement standard construction traffic control procedures, such as the use of flagmen, and signage showing traffic detour plans, haul routes, hours of operation, protective devices, warning signs, and access to abutting properties, that would further reduce any potential impact.
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Education
The 2011 EIR described that the Approved Project would add 364 residential units and an estimated population of 1,149 to the City of Simi Valley. Using Simi Valley Unified School District (SVUSD) standard generation rates for residential development, the Approved Project was estimated in the 2011 EIR to generate approximately 201 new students (117 elementary school students, 29 middle school students, and 55 high school students). The 2011 EIR determined that e nrollment at the elementary schools serving the Project Site would exceed capacity with the add ition of the students that would be generated by the Approved Project. However, with payment of the SVUSD developer fees as required by MM
4.14-1, the 2011 EIR determined that the Approved Project’s impacts related to education would be less than significant.
Parks and Recreational Facilities
The 2011 EIR disclosed that the Approved Project would result in the development of 364 residential units, which would add an estimated 1,149 residents to the City of Simi Valley.
These residents would be expected to use the existing Rancho Simi Recreation and Park District (RSRPD) facilities, thus incr easing demand for parks and recreational amenities within the City.
The 2011 EIR found that State and local laws that require development projects to dedicate parklands or pay fees in lieu of parkland dedication in order to expand and maintain park facilities would minimize the Approved Projec t’s impacts related to parks and recreational facilities to a less than significant level, as outlined in mitigation measure 4.15-1 Prior to final tentative tract map recordation the applicant shall pay to the Rancho Simi Recreation and Park District the applicable facilities fees as determined by the district.
Also, to reduce impacts of the Approved Project to less than significant levels, mitigation measure 4.15-2 was required for the Project, which requires that prior to tentative tract map approval, a conservation mechanism shall be prepared for the preserved open space areas within the Project site, and subject to approval by the City Attorney.
Mitigation Program
• 4.12-1. Prior to issuance of grading plans the applicant shall prepare and submit to the City Planning Department for review and approval a construction traffic control plan including procedures such as the use of flagmen, and signage showing traffic detour plans, haul routes, hours of operation, protective devices, warning signs and access to abutting properties would further reduce any potential impact. The traffic control plan shall restrict construction traffic to Tapo Canyon Road and Lost Canyons Road only, and prohibit construction traffic on Anderson Drive, Ditch Road, Presidio Drive, Walnut Street, and Erringer Road.
• 4.12-2. During all grading and site clearance activities, the applicant’s general contractor shall ensure that all construction traffic is restricted to using Tapo Canyon Road and Lost Canyons Drive only per the approved traffic control plan, and all earth- moving equipment shall be equipped with spark arrestors and at least two portable 1085
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fire extinguishers per vehicle. All equipment used in the vegetation clearance phase shall be equipped with spark arrestors and best available fire safety technology. The vegetation-clearance activities shall be coordinated with and approved by the VCFPD. • 4.12.-3. Prior to the issuance of building permits, the applicant shall submit proof that all structures adjacent to open space shall be designed to satisfy at least a 1-hour fire- resistant rating. Such structures shall incorporate fire retardant features such as boxed-in eaves, reduced overhangs, double -paned windows, convection resistant roof design, non -combustible roofing material, and related design features, as determined necessary by the VCFPD set forth in the City of Simi Valley Building Code (Ventura County Fire Protection District, Fire Prevention Standard 14.3.1). Building permits shall not be issued until review of fire -retarding architectural features has been completed by the VCFPD and City of Simi Valley Building and Safety Division.
Design st andards meeting VCFPD City of Simi Valley Building and Safety Division criteria shall be included in the Fire Hazard Reduction Program and incorporated into the Fire Hazard Reduction Design Guidelines for the residential units (City of Simi Valley Development Code, Section 9-30.030).
• 4.12-4. Prior to tentative map approval, the applicant shall submit drawings indicating that adequate access points, water mains, fire hydrants, valve connections, and other fire protection facilities is provided as required to VCFPD for review and approval.
• 4.12-5. Prior to issuance of building permits, the applicant shall submit fire protection improvement plans to the City of Simi Valley and VCFPD for review and approval.
Upon approval of the plans, the VCFPD shall certify in writing to the City Department of Engineering that the proposed fire protection improvements have been found to be satisfactory.
• 4.12-6. Prior to issuance of occupancy permits, the applicant shall submit a plan for delineating building addresses for purposes of emergency response to the City of Simi Valley and VCFPD for review and approval.
• 4.12-7. Prior to issuance of building permits tentative map approval, the applicant shall pay the required fire protection facilities fees for each applicable structure. • 4.12-8. Prior to the issuance of building permits, the applicant shall provide proof to the City Building Department of compliance with all applicable building and fire code requirements for items such as types of roofing materials, building construction, brush clearance, fire hydrant flows, hydrant spacing, access and design, fire sprinkler systems, and other hazard reduction programs, as set forth by the VCFPD. • 4.12-9. Prior to tentative map approval, the applicant shall submit proposed street alignments, grades, widths, lengths, and turning radii to VCFPD and City Engineer for review and approval.
• 4.12-10. Prior to tentative map approval, the applicant shall provide landscape/fuel modification plans prepared by a licensed landscape architect to the VCFPD for review and approval. The use of drought tolerant, fire -resistant, native vegetation shall be incorporated into the landscape/fuel modification plans. 1086
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• 4.13-1. Prior to the issuance of building permits , p rior to final plan approval, the developer of the project shall pay the City's police facilities fee that is required of all new developments to defray the cost of providing increased levels of police protection. The required amount to be paid shall be determined at the time of final plan review. The sum of $150.00 (as of 2009) for each dwelling unit containing not more than one bedroom and the sum of $75.00 (as of 2009) for each additional bedroom contained therein; provided, however, the total fees for any new dwelling unit shall not exceed the sum of $300.00 (as of 2009).
• 4.13-2. Prior to issuance of building permits, the City shall review development plans for the incorporation of defensible space concepts to reduce demands on police services. To the degree feasible, public safety planning recommendations shall be incorporated in to the project plans. The applicant shall prepare of list of project features and design components that demonstrate responsiveness to defensible space design concepts. Review and approval by the City of all defensible space design features incorporated into the project shall occur prior to initiation of the building plan check process.
• 4.13-3. Where feasible, open spaces shall be designed to facilitate easy viewing from patrol cars and by citizens on adjacent streets. To the extent possible —and without destroying the character —access streets and trails shall be incorporated into open spaces for occasional patrols and other emergency vehicles. • 4.13-4. The project would also be required to implement security recommendations during construction and operation regarding site security, lighting, landscaping, building access and visibility, street circulation, building design, and defensible space, which are identified in the form of planning department conditions. These would be identified by the police department during the tentative tract map and residential planned development reviews.
• 4.13-5. To reduce emergency vehicle delays during construction, the applicant shall implement standard construction traffic control procedures, such as the use of flagmen, and signage showing traffic detour plans, haul routes, hours of operation, protective devic es, warning signs, and access to abutting properties, that would further reduce any potential impact.
• 4.14-1. Prior to the issuance of occupancy permits, the developers of future projects within the Specific Plan boundaries shall pay the Simi Valley Unified School District developer fees in the amount of $2.63 per square for residential, and $0.35 per square foot of commercial.
• 4.15-1. Prior to final tentative tract map recordation the applicant shall pay to the Rancho Simi Recreation and Park District the applicable facilities fees as determined by the district.
• 4.15-2. Prior to tentative tract map approval, a conservation mechanism shall be prepared for the preserved open space areas within the Project Site, and subject to approval by the City Attorney
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3.14.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
PUBLIC SERVICES–Would the project:
a) Result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services:
Fire protection?
Police protection?
Schools?
Parks?
Other public facilities?
Would the Project:
a) Result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental i mpacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services:
i) Fire protection?
No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would occur entirely within a Project Site that is designated as a very high fire hazard severity zone by CalFire (CalFire 2025a).
Fire protection services would be provided for the Proposed Project by the VCFPD, under contract with the City of Simi Valley. The 2011 EIR determined that the VCFPD’s resources are adequate to serve the Approved Project, and response times to service calls at the Project Site would meet VCFPD’s standards. The Proposed Project would result in the same number of residential units being developed within a smaller footprint in the same Project Site . As such, the Proposed Project would not require any new or physically altered fire protection facilities beyond what was previously disclosed in the 2011 EIR for the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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ii) Police protection?
No Substantial Change from Previous Analysis. Fire protection services would be provided to the Proposed Project by the VCFPD, under contract with the City of Simi Valley.
The 2011 EIR determined that the VCFPD’s resources are adequate to serve the Approved Project, and response times to service calls at the Project Site would meet VCFPD’s standards.
The Proposed Project would result in the same number of residential units being developed within a smaller footprint in the same Project Site. As such, the Pro posed Project would not require any new or physically altered police protection facilities beyond what was previously disclosed in the 2011 EIR for the Approved Project.
As specified in the 2011 EIR, the Proposed Project mus t implement mitigation measures 4 - 12-1 through and 4.12-10 to reduce impacts related to police protection services.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
iii) Schools?
No Substantial Change from Previous Analysis. The Approved Project would result in the generation of new residents that would utilize local public schools. As with the Approved Project, the Proposed Project would result in enrollment at the elementary schools serving the Project Site that would exceed capacity with the addition of the students that would be generated by the Proposed Project. However, consistent with the findings of the 2011 EIR for the Approved Project, with payment of the SVUSD developer fees as required by MM 4.14- 1, the Proposed Project’s impacts related to education would be reduced to a less than significant level.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
iv) Parks?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would result in an additional 364 residential units within the Project Site.
Using an average household size for Simi Valley of 2.8 persons per household, 364 new residential units would result in approximately 1,020 new residents, which is similar to the number of new residents anticipated in the 2011 EIR (US Census Bureau 2025). These new residents would be expected to utilize existing neighborhood and regional parks and other recreational facilities in t he vicinity of the Project Site. Through the payment of fees as required by mitigation measure 4.15-1, the appropriate levels of service for parks would be maintained to accommodate the Proposed Project . Any new park projects implemented by others using in -lieu fees from the Proposed Project would be subject to their own review pursuant to CEQA.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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v) Other public facilities (libraries)?
No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would result in the generation of new residents that would utilize local public facilities including libraries. It is likely that residents of the Proposed Project would visit the Simi Valley Public Library occasionally, which would incrementally increase demand for library services. However, the Proposed Project would not result in sufficient demand to require the expansion of the existing library or the construction of a new library.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to public services that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to public services continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.15 RECREATION
3.15.1 2011 EIR
The 2011 EIR described that the Approved Project would result in the development of 364 residential units, which would add an estimated 1,149 residents to the City of Simi Valley .
These residents would require recreational facilities and would be expected to use the existing Rancho Simi Recreation and Park District (RSRPD) facilities, thus increasing demand for parks and recreational amenities within the City.
The 2011 EIR disclosed that the Approved Project would include the preservation of natural resources and the provision of a park, golf course and recreational amenities in combination with residential neighborhoods that would partially offset thi s increased demand for recreational amenities.
State and local laws require development projects to dedicate parklands or pay fees in lieu of parkland dedication in order to expand and maintain park facilities , as specified in mitigation measure 4.15 -1. The 2011 EIR determined that the additional population generated by the Approved Project would cause a decrease in the ratio of parkland to residents within the City, from 8.9 acres of parkland per 1,000 residents to 8.8 acres of parkland per 1,000 residents; however, the 2011 EIR determined that the Approved Project would not cause the ratio to drop below the RSRPD standard of 5 acres per 1,000 residents.
Therefore, the 2011 EIR found that the Approved Project would not require the construction of any additional parks or recreation facilities in order to meet the increased recreational demand that would result from the Approved Project.
To ensure the conservation of open space in the Project Site, mitigation measure 4.15-2 was imposed requiring that a conservation mechanism be prepared for the preserved open space in the Project Site.
Overall, the 2011 EIR determined that the Approved Project’s impacts related to recreation would be less than significant with implementation of mitigation measures.
Mitigation Program
• 4.15-1. Prior to final tentative tract map recordation the applicant shall pay to the Rancho Simi Recreation and Park District the applicable facilities fees as determined by the district.
• 4.15-2. Prior to tentative tract map approval, a conservation mechanism shall be prepared for the preserved open space areas within the proposed project site, and subject to approval by the City Attorney.
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3.15.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
RECREATION–Would the project:
(a) Increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?
(b) Include recreational facilities or require the construction or expansion of recreational facilities which might have an adverse physical effect on the environment?
Would the Project:
a) Increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would result in an additional 364 residential units within the Project Site.
Using an average household size for Simi Valley of 2.8 persons per household, 364 new residential units would result in approximately 1,020 new residents, which is similar to the number of new residents anticipated in the 2011 EIR (US Census Bureau 2025). These new residents would be expected to utilize existing neighborhood and regional parks and other recreational facilities in t he vicinity of the Project Site. Through the payment of fees as required by mitigation measure 4.15 -1, the potential physical deterioration that would result from the Proposed Project’s increased demands on parks and recreational facilities would be minimized.
The Proposed Project would not include the development of new community park within the Project Site, which was included with the Approved Project. Instead, the Proposed Project would provide a private recreation center that would serve the future residents, and a lake feature that would serve as a visual amenity and function as a source for irrigation. The lake will operate like a reservoir ; it will maintain a consistent water level for irrigation and provide additional storage capacity during storm events.
During normal operation, there is no discharge pipe flow—water is only pumped into the irrigation system. Storm flows will be released in a controlled manner by sizing a constriction upstream of the discharge pipe to limit outflow to the 10-year storm event. In a 100-year storm, flows will bypass the constriction and enter the discharge pipe directly. In the worst-case scenario, an overland escape path provides an additional safety outlet.
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The Proposed Project would also provide recreational trails in the Project Site. In total, the Proposed Project would provide fewer recreational amenities to future residents than would the Approved Project, which could increase impacts to other recreational facilities. However, this increase related to demand for parks and recreational facilities would be minimized through payment of in-lieu fees.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Include recreational facilities or require the construction or expansion of recreational facilities, which might have an adverse physical effect on the environment?
No Substantial Change from Previous Analysis. The potential environmental effects of the proposed private recreation center and trails have been evaluated in the 2011 EIR as well as within this EIR Addendum. There are no known or likely new recreational facilities that would be needed as a result of the new demand generated by the Proposed Project. Any new park projects implemented by others using in-lieu fees from the Proposed Project would be subject to their own review pursuant to CEQA.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to recreation that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project.
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3.16 TRANSPORTATION
3.16.1 2011 EIR
As part of the development of the 2011 EIR, the capacity was evaluated at 17 intersections in the vicinity of the Project Site with the addition of traffic that was expected to be generated by the Approved Project. As described in the 2011 EIR, u nder existing conditions, the 17 study intersections operated at Level of Service (LOS) A during AM peak hour and PM peak hour conditions. As described in the 2011 EIR, s ite access for the Approved Project was planned via one primary gated access location at the existing intersection of Lost Canyons Golf Club Driveway and Lost Canyons Drive, in addition to a secondary gated access location at the “A” Street/Lost Canyons Drive intersecti on and a secondary gated access location at the “B” Street/Lost Canyons Drive intersection.
The 2011 EIR described that the Approved Project was estimated to generate approximately 2,840 net new daily trips, which would include approximately 233 net new AM peak hour trips and approximately 318 net new PM peak hour trips. With the addition of the Approved Project, the 2011 EIR determined that the 17 study intersections would continue to operate under LOS A conditions during AM peak hour and PM peak hour traffic conditions. Therefore, impacts related to level of service at intersections impacted by the Approved Project were determined to be less than significant.
The signal warrant analysis for the intersections of Lost Canyons Golf Course and Lost Canyons Drive, and Tapo Canyon Road and Lost Canyons Drive that were conducted as a part of the development of the 2011 EIR determined that these intersections did not require a traffic signal. The signal warrant analysis for the intersection of Tapo Canyon Road and Lost Canyons Drive determined that these intersections did require a traffic signal. A traffic signal was also recommended in the 2011 EIR at Lost Canyons Drive and Lost Canyons Golf Course due to the surrounding rolling topography. As a result of these signals being installed as a part of the Approved Project, the 2011 EIR determined that the Approved Project would not substantially increase hazards due to a design feature (e.g., sharp curves or dangerous intersection) and that impacts related to this threshold would be less than significant with incorporation of mitigation measures. Specifically, mitigation measures 4.16-1 through 4.16- 3 were required for the Approved Project to mitigate traffic-related impacts.
As required by mitigation measure 4.16-1, prior to the approval of tract maps, the applicant shall pay the Traffic Impact Fee specified in the City of Simi Valley Schedule of Service Charges (in effect at the time of payment), as stated in Resolution No. 91-93.
As required by mitigation measure 4.16-2, prior to the approval of tract maps, the applicant shall pay the Ventura County Reciprocal Traffic Fee, which is collected by the City of Simi Valley on behalf of the County.
As required by mitigation measure 4.16-3, prior to the issuance of any building final permits for Planning Area 2, installation of a traffic signal at Tapo Canyon Road and Lost Canyons Drive shall be constructed, concurrent with the reconstruction of Tapo Canyon Road. 1094
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As discussed in the 2011 EIR, the Approved Project would be accessible by two main streets (Tapo Canyon Road and Erringer Road) that would provide access to and from the Project Site. Additionally, the Approved Project would incorporate three emergency vehicle access (EVAs) roads in different locations along the boundary of the Approved Project to allow emergency ingress and egress to and from the Project Site. Since the Approved Project would fulfill the need for adequate access to and from the Project Site, impacts related to emergency access to the Project Site would be less than significant.
The 2011 EIR found that the Approved Project would result in a significant impact related to geometric design hazards, requiring implementation of mitigation. As required by mitigation measure 4.16-4, upon completion of the reconstruction of Tapo Canyon Road and after the majority of the project is occupied (but not later than one year after the issuance of occupancy permits for the 200th residential unit for the proposed project) and the general public has utilized Tapo Canyon Road, the posted speed limit on the roadway should be determined via a speed survey that would be conducted by the applicant and submitted to the City Engineer for review and approval. As required by mitigation measure 4.16 -4, appropriate signage indicating the posted speed limit shall be installed upon completion of the speed survey and approval by the City Engineer.
With implementation of mitigation measures 4.16 -1 through 4.16 -4, the 2011 EIR determined that the Approved Project would result in less than significant impacts related to transportation.
Mitigation Program
• 4.16-1. Prior to the approval of tract maps, the applicant shall pay the Traffic Impact Fee specified in the City of Simi Valley Schedule of Service Charges (in effect at the time of payment), as stated in Resolution No. 91-93.
• 4.16-2. Prior to the approval of tract maps, the applicant shall pay the Ventura County Reciprocal Traffic Fee, which is collected by the City of Simi Valley on behalf of the County. The fee due to the County is $12,439.20 based on the Initial Study. This fee may be subject to adjustment at the time of deposit, due provisions in the TIMF Ordinance allowing the fee to be adjusted for inflation based on the Engineering News Record Construction Cost Index.
• 4.16-3. Prior to the issuance of any building final permits for Planning Area 2, installation of a traffic signal at Tapo Canyon Road and Lost Canyons Drive shall be constructed, concurrent with the reconstruction of Tapo Canyon Road. • 4.16-4. Upon completion of the reconstruction of Tapo Canyon Road and after the majority of the project is occupied (but not later than one year after the issuance of occupancy permits for the 200th residential unit for the proposed project) and the general public has utilized Tapo Canyon Road, the posted speed limit on the roadway should be determined via a speed survey to be conducted by the applicant and submitted to the City Engineer for review and approval. Appropriate signage indicating the posted spe ed limit shall be installed upon completion of the speed survey and approval by the City Engineer.
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3.16.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
TRANSPORTATION – Would the project:
a) Conflict with a program plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities?
b) Would the project conflict or be inconsistent with CEQA Guidelines section 15064.3, subdivision (b)?
c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?
d) Result in inadequate emergency access?
The responses in this section are partially based on a Transportation Technical Memorandum that was prepared for the Proposed Project by Michael Baker International in January 2025 (Michael Baker International 2025e).
Would the project:
a) Conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities? No Substantial Change from Previous Analysis. The Proposed Project would not conflict with any of the goals, policies, or plans that are contained in the City of Simi Valley’s General Plan Mobility & Infrastructure Element or within the City’s Bicycle Master Plan (Simi Valley, 2008a and 2012a).
The Proposed Project would result in an increase in daily trips from the 2,840 net new daily trips that were anticipated for the Approved Project to a total of 3,483 trips per day that are anticipated that are anticipated to be generated for the Proposed Project.
As a result, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Would the project conflict or be inconsistent with CEQA Guidelines section 15064.3, subdivision (b)?
No Substantial Change from Previous Analysis. State CEQA Guidelines Section 15064.3, subdivision (b) provides the criteria for analyzing transportation impacts, and a project’s effect on automobile delay shall not constitute a significant environmental impact (OAL 2019). Generally, vehicle miles trave led (VMT) is the most appropriate measure of transportation impacts. VMT refers to the amount and distance of automobile travel attributable to a project.
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This threshold was not explicitly addressed in the 2011 EIR since this threshold was not part of Appendix G of the State CEQA Guidelines at the time the 2011 EIR was prepared. However, the issue of VMT is not new information that was not known or that could not have been known at the time of the certification of the 2011 EIR. In fact, the Project’s anticipated VMT effects were discussed in the air quality analyses contained in the 2011 EIR.
The Proposed Project would result in similar VMT effects as would the Approved Project given that both would result in the same number of residential units, which are the primary driver of VMT for both the Proposed Project and the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses? No Substantial Change from Previous Analysis. The Proposed Project would not introduce any geometric design features or incompatible land uses that were not previously evaluated in the 2011 EIR for the Approved Project. Mitigation measure 4.16-4 would apply to the Proposed Project, which requires that upon completion of the reconstruction of Tapo Canyon Road and after the majority of the project is occupied (but not later than one year after the issuance of occupancy permits for the 200th residential unit for the proposed project) and the general public has utilized Tapo Canyon Road, the posted speed limit on the roadway should be determined via a speed survey that would be conducted by the applicant and submitted to the City Engineer for review a nd approval. As required by mitigation measure 4.16-4, appropriate signage indicating the posted speed limit shall be installed upon completion of the speed survey and approval by the City Engineer. With implementation of mitigation measure 4.16 -4, the Proposed Project would have similar effects related to this threshold as would the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) Result in inadequate emergency access?
No Substantial Change from Previous Analysis. The 2011 EIR determined that the Approved Project would not impair the implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. The 2011 EIR discussed that the Proposed Project would include adequate p rimary and secondary access roads, which would allow for adequate access during an emergency such as a wildland fire.
The Proposed Project would result in similar impacts related to emergency evacuation as would the Approved Project given that the Proposed Project would result in similar roadway infrastructure being developed to evacuate the Project Site and because the A pproved Project would not result in an increase in the number of units or individuals that would need to evacuate the Project Site when compared to the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
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Conclusion
The Proposed Project would not result in any new or substantially increased effects related to transportation that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to transportation continue to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.17 TRIBAL CULTURAL RESOURCES
3.17.1 2011 EIR
The 2011 EIR was circulated before implementation of Assembly Bill 52 (AB 52) , which requires that a lead agency to engage in consultation with a California Native American tribe that is traditionally and culturally affiliated with the geographic area of the proposed project.
Prior to release a negative declaration, mitigated negative declaration, or an EIR for a project, the lead agency shall begin consultation with a California Native American tribe that is traditionally and culturally affiliated with the geographic area of the proposed project. (Pub.
Res. Code § 21080.3.1(b).) AB 52 ; however, does not apply to EIR Addendums. As such, the Proposed Project would not trigger the tribal consultation requirements of AB 52.
Nonetheless, the 2011 EIR did disclose that there were seven archaeological sites and nine isolated occurrences of prehistoric artifacts within the Project Site. As part of the development of the 2011 EIR, Phase I and Phase II investigations of the seven archaeological sites in the Project Sit e were conducted, which determined that these sites were not significant and that no additional studies of these sites were warranted. The 2011 EIR found that the Approved Project had a potential to result in the disco very of unknown archaeological resources in the Project Site. Mitigation measures 4.4. -1 through 4.4-5 were required for the Approved Project to mitigate impacts related to archaeological resources to less than significant levels.
The 2011 EIR found that there were no known cemeteries or burial grounds on the Project Site, but that the Project Site has a history of use by Native Americans. Therefore, the 2011 EIR determined that there was potential for the discovery of human remains , including unmarked burial grounds. Because the potential exists for human remains to be unearthed during the Proposed Project’s grading activities, mitigation measure 4.4 -6 was required for the Approved Project to mitigate impacts related to human remains.
Mitigation Program
See mitigation measures provided in Section 3.4, Cultural Resources. 1099
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3.17.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
TRIBAL CULTURAL RESOURCES – Would the project:
a) Would the project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
i) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code section
5020.1(k), or
ii) A resource determined by the lead agency, in its
discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1. In applying the criteria set forth in subdivisio n (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native
American tribe.
Compliance with AB 52 pertaining to Native American Tribal Consultation is required for projects with publicly circulated CE QA documents, such as EIRs, MNDs, or NDs filed on or after July 1, 2015. The present Addendum does not require circulation for public review; thus, discussion of the tribal consultation process and analysis of impacts to tribal cultural resources is not required here. However, for informational purposes, an analysis is provided below.
Would the Project:
a) Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code Section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
i) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code Section 5020.1(k)? and
ii) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1? In applying the 1100
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criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.
No Substantial Change from Previous Analysis. The updated record search and archival research results that were conducted for the Proposed Project did not substantively change the overall context, or the documented cultural sensitivity that was previously addressed in the 2011 EIR.
The Proposed Project would result in fewer overall impacts when compared to the Approved Project. The 2011 EIR disclosed that the Approved Project would result in direct impacts to a total of 790.72 acres of land. The Proposed Project would impact a total of 305.22 acres of land, which is a reduction in impacts of 485.50 acres ( Chambers Group, 2024a). By substantially reducing the acreage of impacts, the Proposed Project would also reduce the potential for impacts to occur related to tribal cultural resources.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to tribal cultural resources that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. The mitigation measure from the 2011 EIR relating to tribal cultural resources continue s to apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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3.18 UTILITIES AND SERVICE SYSTEMS
3.18.1 2011 EIR
Water
The 2011 EIR disclosed that the Approved Project would add residential and commercial users to the Ventura County Water Works District (VCWWD) No. 8 service area, which would create additional demands for water within the districts.
The 2011 EIR described that the Approved Project would be divided into two primary water pressure zones, and would be served by three potable water tanks. One potable water tank is proposed within the project site, and two existing tanks are located in Sand Canyon.
The 2011 EIR described that water would be supplied to a new pump station from the 1355 Pressure Zone, which would require pump station upgrades, including modification to the pumps and pipelines. The 2011 EIR described that a looped pipeline system would connect existing facilities located at the intersection of Tapo Canyon Road and Lost Canyons Drive to a new approximately 1 -million-gallon reservoir within the Project Site and to the existing 16-inch transmission pipeline located within Lost Canyons Drive . The 2011 EIR described that a new pipeline within Dry Canyon would connect to the new line within Lost Canyons Drive, with a pressure regulating station near the southern boundary of the project site to connect the two water pressure zones. As described in the 2011 EIR, water would be pumped to the new station from the existing pump station located on Tapo Street, which would require upgrades to existing pumps and pipelines.
The 2011 EIR evaluated the adequacy of existing water supplies and the water distribution system to serve the uses that would be allowed by the Approved Project. The 2011 EIR described that potable water for the Approved Project would be provided by VCWWD No. 8, which receives SWP water from CMWD. Water service at the Project Site would be provided by the Ventura County Waterworks District No. 8 (VCW WD No. 8), which purveys water provided by Calleguas Municipal Water District (CWMD). The 2011 EIR reported that at the time of the preparation of the 2011 EIR, VCWWD No. 8 delivered more than 23,000 acre-feet of water to approximately 24,000 service connections. The 2011 EIR determined that there were adequate VCW WD No. 8 facilities to provide potable and non -potable water to the Project Site. The 2011 EIR found that improvements to the existing potable water distribution system would be required to serve the Approved Project. However, the 2011 EIR found that no improvements to potable water treatment facilities would be required in order to serve the Approved Project.
The 2011 EIR described that the Approved Project would include improvements to the water delivery system that was required based on a new grading plan developed around the clubhouse area of the Approved Project . As described in an engineering letter that was prepared as a part of the development of the 2011 EIR , approximately 16 lot elevations would experience service pressures below 30 pressure pounds per square inch (psi) after a maximum day demand. As such, t hese lots would require service from a hydropneumatic station or other alternative approved by the VCWWD No. 8. As required by mitigation 1102
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measure 4.17-1, prior to the issuance of occupancy permits, the applicant shall construct new water storage tank and a new hydropneumatic booster pump station (Los Canyons Booster Pump Station) as part of the Project to provide service pressures above 30 psi for lot elevations with pressures less than 30 psi that would comply with VCWWD No. 8 district service pressure requirements and approved by the Director of Public Works. In light of this no lots would experience service pressure below 30 psi.
As discussed in the 2011 EIR , a majority of the water distributed by VCWWD No. 8 was imported SWP water. This water was treated by MWD and did not require additional treatment prior to distribution. As such, the Approved Project was determined to not require additional water treatment improvements.
At the time of the preparation of the 2011 EIR, t he most recent urban water management plans prepared by VCWWD No. 8 and CWMD indicate d that there was sufficient supplies of water available to supply current and projected demand for the district, including the Approved Project . The 2011 EIR found that t he additional demand generated by the Approved Project would result in an approximately 238.5 acre -feet per year (afy), approximately 1 percent increase in water use within VCW WD No. 8. This would represent 3 percent of the 7,925 -afy increase in potable water demand over the 20 -year planning period covered by VCW WD’s 2005 UWMP. As previously discussed, VCW WD No. 8 has a long-term contract with CMWD to provide 100 percent of the water requested, based on availability.
As such, the 2011 EIR determined that the Approved Project’s impacts related to water would be less than significant.
Wastewater
The 2011 EIR described that the Project Site was not served by the City’s sewer system. At the time of the development of the 2011 EIR, wastewater generated by the golf courses and associated structures were stored in an on -site septic tank system . At the time of the development of the 2011 EIR, City sewer lines served adjacent areas to the west and south of the Project Site but did not serve the Project Site itself. The golf course and commercial development were removed from the project.
The 2011 EIR evaluated wastewater impacts for the Approved Project at a conceptual planning level, relying on preliminary sewer studies and assumptions available at that time.
The EIR concluded that certain off -site sewer improvements and upsizing of downs tream pipe segments would be required to accommodate project -generated flows and avoid capacity constraints.
Subsequent to the 2011 EIR, the City approved the Lost Canyons Sewer System Master Plan Addendum, which provided a detailed, pipe -by-pipe hydraulic analysis of the same downstream sewer system using updated City GIS data, refined tributary area delineation s, and City-standard hydraulic design criteria.
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In contrast with the 2011 EIR , the 2017 Master Plan Addendum demonstrates that all evaluated 8-inch and 12-inch sewer segments operate within allowable City capacity criteria under post-development peak flow conditions, with no surcharge or exceedance of design depth limits.
The 2011 EIR described that the Approved Project would result in the development of 364 residential units, along with commercial and commercial recreation uses, which would discharge wastewater to existing sewer lines through new connections to existing sewer lines at Tapo Canyon Road and Valerie Avenue , and via a proposed new sewer line within Anderson Drive, extending from the project boundary to Avenida Simi and then southerly within Sycamore Drive to Cochran Street as described in more detail below.
The 2011 EIR described that the Proposed Project would include construction of the sewer lines necessary to convey wastewater from the proposed residential and commercial uses to existing sewer mains. The 2011 EIR included a c onceptual sewer plan that sho wed the conceptual wastewater conveyance system prepared for the Approved Project in the sewer study that was prepared at that time. In order to determine the size of the new sewer mains, a wastewater generation factor of 275 gallons per day (gpd) per dwelling unit was used as a part of the Approved Project’s sewer study, which was based on the City’s wastewater design standards. The Project Site was divided into five drainage areas as a part of the sewer study, and flow rates were calculated and a peaking factor was added for each area to determine the design flow of each stretch of pipe. Proposed lines were tied into the existing wastewater conveyance system and checked to determine adequacy of the downstream mains. Based on calculations in the sewer study, 8-inch lines would be required to convey flows generated by the Approved Project’s proposed uses to sewer mains. The 2011 EIR disclosed that i n Area B of the Project Site, a pump station would be required to convey flows through a 3-inch force main to an 8-inch gravity line. These lines are existing. In order to provide sewer service to the Approved Project, which is currently unserved by the City’s sewer system. The Approved Project proposed two new connections to existing sewer lines to accommodate the proposed development. Two connections would be made to existing sewer lines in Tapo Canyon Road at Presidio Drive and Valeria Avenue at Presidio Drive and Lost Canyon Drive. .
The 2017 Master Plan Addendum demonstrates that, when evaluated using City design standards and updated data, the same downstream system can accommodate project flows without physical upgrades. This indicates that the off -site improvements identified in the 2011 EIR were conservative planning assumptions rather than confirmed engineering requirements.
The 2011 EIR determined that the Approved Project would not exceed the wastewater treatment requirements of the applicable RWQCB and this is corroborated by the 2017 Sewer Master Plan . The 2011 EIR disclosed that implementation of the Approved Project would result in the generation of wastewater flows, which would be conveyed to the City’s WQCP for treatment before discharge into Arroyo Simi. The 2011 EIR described that the Los Angeles RWQCB had adopted waste discharge requirements regulating the discharge of tertiary treated effluent from the WQCP to Arroyo Simi within the Calleguas Creek Watershed. Most of the surface water within the watershed has been identified as impaired, meaning it does not fully support designated beneficial uses such as water supply or wildlife 1104
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habitat. The 2011 EIR determined that the Approved Project would not alter the requirements of the Los Angeles RWQCB, and therefore would have no impact related to exceedance of applicable wastewater treatment requirements of the applicable Regional Water Quality Control Board . The 2011 EIR summarized the projected wastewater generation of the Approved Project, based on generation rates provided in the sewer study.
As shown in the 2017 sewer master plan, the Approved Project would generate an estimated 100,100 gpd, or 0. 10 mgd, of wastewater. As previously discussed, the City’s WQCP has a rated capacity of 12.5 mgd and currently treats approximately 8 mgd, with an available capacity of 4.5 mgd at the time the 2011 EIR was prepared. As such, the 2011 EIR determined that the Approved Project’s wastewater generation of 0.10 mgd could be accommodated by the WQCP’s existing capacity. The 2011 EIR also disclosed that the City had plans to expand capacity at the WQCP to 17.5 mgd by 2014. The expansion has not been necessary because wastewater flows have decreased since 2011. As such, the project is not anticipated to result in wastewater generation in excess of existing City system capacity . T herefore, the 2011 EIR and 2017 sewer master sewer plan found that no new sewer treatment facilities would need to be constructed to accommodate the Approved Project. Accordingly, the 2011 EIR found that the Approved Project would not exceed wastewater treatment requirements of the Los Angeles RWQCB and impacts would be less than significant with implementation of mitigation measures 4.18-1 and 4.18-2.
As required by mitigation measure 4.18-1, prior to approval of tentative tract maps, the applicant shall pay fees in accordance with Development Code Section 9 -66.050 to the City of Simi Valley.
As required by mitigation measure 4.18-2, t he applicant shall be responsible for the construction of all on -site and off-site sanitary sewer faculties and connections required to serve the Approved Project. Also, as required by mitigation measure 4.18 -2, the applicant shall enter into an agreement with City of Simi Valley Department of Public Works to construct the improvements and the system shall be dedicated to City of Simi Valley for maintenance.
With implementation of mitigation measures 4.18 -1 and 4.18 -2, the Approved Project was determined to have less than significant impact related to sewer systems.
Solid Waste
The 2011 EIR discussed that the Approved Project would result in demands for solid waste during construction and operation.
The 2011 EIR discussed that the construction of the Approved Project would involve grading and construction, which would result in the generation of construction waste. The 2011 EIR found that s mall amounts of demolition waste would be generated from the demolition of the existing golf course currently occupying a portion of the Project Site . The 2011 EIR discussed that c onstruction-related solid waste materials would be typical construction debris, including wood, paper, glass, plastic, metals, cardboard, and green wastes. The 2011 EIR disclosed that the wastes generated would result in an incremental and intermittent increase in solid waste disposal at the Simi Valley Landfill. 1105
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The 2011 EIR describe that development of the Approved Project would result in 364 residential units and a minor amount of new commercial use at buildout. The 2011 EIR disclosed that the residents of these units would generate solid waste that would be collected and disposed of in the SVLRC. The 2011 EIR included estimated solid waste generation and determined that it would be able to be accommodated at the Simi Valley Landfill.
The 2011 EIR described that the City of Simi Valley Department of Community Services oversaw solid waste collection in the City. The 2011 discussed that solid waste collection in the City was provided by two private refuse collectors: GI Rubbish and Anderson Rubbish.
GI Industries, an affiliate of GI Rubbish, provide d residential collection services in the City.
The 2011 EIR discussed that the property owners in the City are responsible for contracting directly with haulers for solid waste collection and disposal services. The 2011 EIR described that the l ocal haulers pick ed up municipal solid waste from customers within the City and transported it to the Simi Valley Landfill and Recycling Center (SVLRC). The 2011 EIR discussed that the SVLRC had a permitted daily capacity of 3,000 tons per day (tpd) and received an average of 2,177 tpd, leaving available capacity of 823 tpd. The 2011 EIR found that the 1.69 tpd that would be generated by the Approved Project would require less than 1 percent of the remaining available capacity for this landfill . As such, the 2011 EIR found that the Approved Project’s solid waste would, therefore, be able to be accommodated at the SVLRC, which the 2011 EIR determined had adequate remaining capacity to accept the Approved Project’s solid waste until its projected closure in 2033. The 2011 EIR concluded that the Approved Project would be served by a landfill with sufficient permitted capacity, and impacts would, therefore, be less than significant.
Mitigation Program
• 4.17-1. Prior to the issuance of occupancy permits, the applicant shall provide a hydropneumatic booster pump station or a higher storage tank high water level and required piping to provide service pressures above 40 psi for lot elevations with pressures less than 30 psi that would comply with VCWWD No. 8 district service pressure requirements and approved by the Director of Public Works. • 4.18-1. Prior to approval of tentative tract maps, the applicant shall pay fees in accordance with Development Code Section 9-66.050 to the City of Simi Valley. • 4.18-2. The applicant shall be responsible for the construction of all on -site and off- site sanitary sewer faculties and connections required to serve the project. The applicant shall enter into an agreement with City of Simi Valley Department of Public Works to construct the improvements and the system shall be dedicated to City of Simi Valley for maintenance.
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3.18.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
UTILITIES AND SERVICE SYSTEMS – Would the project:
a) Require or result in the relocation or construction of new or expanded water, or wastewater treatment or storm water
drainage, electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects?
b) Have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry and multiple dry years?
c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments?
d) Generate solid waste in excess of State or local standards, or in excess of the capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction goals?
e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
Would the Project:
a) Require or result in the relocation or construction of new or expanded water, wastewater treatment or storm water drainage, electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects?
No Substantial Change from Previous Analysis.
Water
The Proposed Project , similar to the Approved Project, would add residential users to the area. Additionally, the Project would generate visitors to the clubhouse and recreation center. However, it should be noted that while the Proposed Project includes a clubhouse and recreation center, the prior golf course is considered a commercial level golf course with a sit-down restaurant, support facilities such as a clubhouse (including a central building with locker rooms, restrooms, lounges, and administrative offices) , practice areas, guest amenities, and maintenance infrastructure. Therefore, the Proposed Project would not result in more water demand compared to the Appro ved Project , which was a fully developed commercial level golf course.
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ADDENDUM NO. 1 TO THE EIR
A Water System Master Plan was prepared for the Proposed Project, which has estimated water demands for the Proposed Project and identified water distribution requirements for the Proposed Project (RTM Engineering Consultants 2025b). As outlined in the Water System Master Plan, the Proposed Project would include 364 residential lots, a recreation center with a lake, drainage basins, and associated infrastructure. The Water System Master Plan identified that the Proposed Project’s service pad elevations would range in elevation from approximately 1215 to approximately 1416 feet. T he Water System Master Plan describes that the Proposed Project’s recreation center and 140 lots would be served by the 1470 Pressure Zone by connecting to the existing 16” water line in Lost Canyons Drive, and that 222 lots would be served by a new 1537 pressure zone. The Water System Master Plan described that d uring final design, the delineation between the 1470 and 1537 pressure zones may be refined to optimize water system performance and residential lot pressures.
The Water System Master Plan described that two lots that would be located on the southern portion of the Project Site would be serviced by joining existing City owned water pipes.
Specifically, the first lot would connect to an existing 8” water line in Anderson Drive in the existing 1248 pressure zone. The second lot w ould connect to an existing 8” water line in Ditch Road in the existing 1355 pressure zone (RTM Engineering Consultants 2025b).
The Water System Master Plan describes that in addition to the residential demand for potable water, w ater demand would also result from the Homeowner’s Association (HOA) community landscape. Water for the community’s landscaping would be supplied from the proposed potable water system via an air-gapped connection to the existing 200,000-gallon tank. Also, the Proposed Project’s proposed lake w ould have a connection to the domestic water system which would be used to offset evaporation loss when the non -potable supply is not available. A demand of 25 gpm was calculated using an evaporation loss factor of 0.5 inches of lake depth per day (RTM Engineering Consultants 2025b).
The Water System Master Plan also includes an evaluation of the required fire flow that would be needed to serve the Proposed Project. The Ventura County Fire Protection District (VCFPD) directed that the residential fire flow requirements for the Proposed Project be determined using the California Fire Code. The hydraulic model simulations provided in the Water System Master Plan assumed that both the fire hydrant and fire sprinkler demands would be applied simultaneously. Fire storage volume were calculated and were used to determine the Proposed Project’s proposed reservoir size as well as the pump station flow rate that is needed (RTM Engineering Consultants 2025b).
As outlined in the Water System Master Plan, the water storage requirement for the Proposed Project would be met by the new 1537 reservoir that would be built as a part of the Proposed Project and will serve 222 lots as well as the existing Big Sky 1470 tank. The 1537 reservoir would be supplied by the new 1537 Lost Canyons Booster Pump Station. The sizing of the 1537 reservoir was determined by using the VCWWD No. 8 storage requirements that are presented in the Water System Master Plan . The calculations for reservoir storage take into account requirements related to operational storage, emergency storage, and fire storage volume (RTM Engineering Consultants 2025b). The reservoir provides sufficient capacity for the 1537 zone and includes a surplus storage of +48,691 gallons. The Project will utilize the previously approved plans for a 580,000-gallon reservoir, with revisions. The updated design will accommodate a dedicated transmission pipe from 1108
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the new Lost Canyons booster pump station to the new reservoir (superseding the previous design which included a combined transmission/distribution pipe). The new tank will have a water height of 24 feet, a diameter of 64 feet, and will be situated at a pad elevation of 1,513 feet. These revisions must be reviewed and approved by the VCWWD No. 8 prior to construction.
The Proposed Project would require the construction of a pump station. As outlined in the Water System Master Plan, a new 1537 Pump Station has been designed and appro ved by the city for the Proposed Project . According to the Water System Master Plan, the pump station was designed to deliver the MDD volume for the 1537 and 1470 zones within 12 hours to incorporate Southern California Edison (SCE) off peak pumping guidelines. The pump station was also designed to replace the required fire storage volume (FS V) for a period of 72 hours. The new 1537 Pump Station would be constructed at the southeast corner of the Project Site at the intersection of Street “U” and Lost Canyons Drive. As detailed in the Water System Master Plan, the City requested that this new pump station be sized so that it can provide fire flow when the proposed 1537 tank is offline for maintenance.
Therefore, the pump station has been designed for the Proposed Project to include three vertical turbine pumps (VTP) (alternating for even wear), each rated for 800 gpm. In the case of fire, when the 1537 tank is offline, the pump station would have the capability of providing the fire flow (540 gpm) plus maximum day demand (139 gpm) in the 1537 zone.
It was previously thought that when the Approved Project became operational, it may cause a reduced suction pressure at the existing 1715 pump station on Tapo Canyon Road , which is located north of the Proposed Project’s proposed Lost Canyon Pump Station. However, now that the new Walnut Ave pump station has been designed and will be constructed to replace the existing Tapo St. pump station, the low pressure issue at the 1715 pump station will be mitigated when the new Walnut Ave. pump station becomes operational. An alternate solution, if the low pressure issue persists after the Walnut Ave. pump station is operational, would be to run the existing 1715 pump station during the 12 hours each day when the new Lost Canyons pump station is shut down, so these two booster pump stations have no effect on each other. These final details would be evaluated in consultation with the City and VCWWD prior to implementation of the Proposed Project.
The Proposed Project would install a new looped water supply system for reliability of service. The developer would construct a 12” water pipeline that would connect the existing 1355 zone at the intersection of Tapo Canyon Road and Lost Canyons Drive to the proposed Lost Canyons 1537 Reservoir. The final alignment and design would be reviewed and approved by the City prior to implementation . According to the Water System Master Plan, there will also be a connection to the existing 16 -inch pipeline in Lost Canyons Drive, that was constructed by the Big Sky development, thereby creating a looped system.
As described previously, the two individual lots at the southern end of the Project Site would be served by the existing 1248 and 1357 zones by connecting to existing water pipes in Anderson Drive and Ditch Road.
The Proposed Project would construct a pressure regulating station for reliability of the overall water system. The pressure regulating station would connect the 1537 Pressure Zone 1109
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to the 1470 Pressure Zone and would be located within the Proposed Project, near the main entrance of the residential development.
As detailed in the Water System Master Plan , the Proposed Project’s proposed d omestic water infrastructure, including the proposed reservoir, pump station and pipelines would comply with the requirements of the VCWWD No. 8, the City of Simi Valley, and the Ventura County Fire Department.
All of the potable water infrastructure proposed for the Proposed Project would occur within the impact footprint previously evaluated in the 2011 EIR. As such, the Proposed Project would not result in any new or increased impacts related to potable water that were not previously analyzed.
Wastewater
The Proposed Project , similar to the Approved Project, would add residential users to the area. Additionally, the Project would generate visitors to the clubhouse and recre ation center. However, it should be noted that while the Proposed Project includes a clubhouse and recreation center, the prior golf course is considered a commercial level golf course with a sit-down restaurant, support facilities such as a clubhouse (including a centr al building with locker rooms, restrooms, lounges, and administrative offices), practice areas, guest amenities, and maintenance infrastructure. Therefore, the Proposed Project would not result in more demand for wastewater conveyance and treatment compared to the Approved Project.
A Sewer System Master Plan was prepared for the Proposed Project, which has estimated wastewater generation estimates for the Proposed Project and has identified sewer conveyance requirements for the Proposed Project (RTM Engineering Consultants 2025 c).
As detailed in the Sewer System Master Plan, the existing sewer system is sufficiently sized to convey the additional sewage flow that would result from the Proposed Project without requiring any off-site sewer infrastructure upgrades. The calculations prepared as a part of the Sewer System Master Plan show that all 8” pipes would convey sewage at a maximum depth of 0.28’, which would be less than the City of Simi Valley’s maximum of 1/2 full (0.33’ in an 8” pipe). Additionally, the existing 12” pipe would be capable of conveying sewage at a maximum depth of 0.63’, which is less than the City of Simi Valley’s maximum of 2/3 full (0.67’ in a 12” pipe). Anticipated sewage flows and depths at each of the off -site confluence points are provided in the Sewer System Master Plan.
As required by mitigation measure 4.18-1, p rior to approval of tentative tract maps, the applicant shall pay fees in accordance with Development Code Section 9 -66.050 to the City of Simi Valley.
As required by mitigation measure 4.18 -2, the applicant shall be responsible for the construction of all on -site and off-site sanitary sewer facilities and connections required to serve the Proposed Project. Also, as required by mitigation measure 4.18 -2, the applicant shall enter into an agreement with City of Simi Valley Department of Public Works to construct the sewer improvements and the sewer system shall be dedicated to City of Simi Valley for maintenance.
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ADDENDUM NO. 1 TO THE EIR
With implementation of mitigation measures 4.18-1 and 4.18-2, the Proposed Project would not result in any new or increased impacts related to wastewater.
Solid Waste
As with the Approved Project, the Proposed Project would result in increased demand for solid waste during construction and operation.
Similar to the Approved Project, the Proposed Project would result in the generation of small amounts of demolition waste from the demolition of the existing golf course facilities that occupy a portion of the Project Site.
Also, the Approved Project would result in 364 residential units and a clubhouse and recreation center uses at buildout that would result in ongoing generation of solid waste. As with the Approved Project, the Proposed Project would result in additional solid waste needing to be disposed of at the Simi Valley Landfill. However, it should be noted that while the Proposed Project includes a clubhouse and recreation center, the prior golf course is considered a commercial level golf course with a sit-down restaurant, support facilities such as a clubhouse (including a cent ral building with locker rooms, restrooms, lounges, and administrative offices), practice areas, guest amenities, and maintenance infrastructure.
Therefore, the Proposed Project would not result in more solid waste generation compared to the Approved Project.
Solid waste for the Proposed Project would likely be disposed of at the Simi Valle Landfill.
Located northwest of the city of Simi Valley, the Simi Valley Landfill & Recycling Center (SVLRC) is a fully permitted non -hazardous municipal solid waste landfill and recycling facility that has served Ventura County for over 40 years. The SVLRC first opened in 1970 and Waste Management acquired the facility in 1983. The SVLRC is estimated to have remaining capacity of approximately 80 million cubic yards (Waste Management 2025a).
As with the Approved Project, the Proposed Project would be able to be accommodated at regional landfills, including the SVLRC. As such, the Approved Project would have less than significant impact related to solid waste.
Conclusion
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Have sufficient water supplies available to serve the Project and reasonably foreseeable future development during normal, dry and multiple years? No Substantial Change from Previous Analysis. As described above, the Proposed Project would include the development of adequate infrastructure to connect the Proposed Project’s units and landscaping to the municipal water system.
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A Water System Master Plan was prepared for the Proposed Project, which estimated water demands for the Proposed Project and identified water distribution requirements for the Proposed Project (RTM Engineering Consultants 2025b).
As detailed in the Water System Master Plan, the Proposed Project’s proposed domestic water infrastructure, including the proposed reservoir, pump station and pipelines would comply with the requirements of the VCWWD, the City of Simi Valley, and the Ventura County Fire Department.
The VCWWD’s 2020 Urban Water Management Plan ( UWMP) included assumptions that residential development would occur in the Project Site to a similar extent to what is proposed by the Proposed Project. Further, the UWMP demonstrated that the VCWWD would have adequate water supplies available to serve its users during normal, dry, and multiple dry years (Waterworks District No. 8 2020).
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments? No Substantial Change from Previous Analysis. As described above, the Proposed Project would include the development of adequate infrastructure to connect the Proposed Project’s residential units and clubhouse to the existing off-site sewer system.
A Sewer System Master Plan was prepared for the Proposed Project, which estimated wastewater generation estimates for the Proposed Project and has identified sewer conveyance requirements for the Proposed Project (RTM Engineering Consultants 2025c).
As detailed in the Sewer System Master Plan, the existing sewer system is sufficiently sized to convey the additional sewage flow that would result from the Proposed Project without requiring any off-site sewer infrastructure upgrades. The calculations pre pared as a part of the Sewer System Master Plan show that all 8” pipes would convey sewage at a maximum depth of 0.28’, which would be less than the City of Simi Valley’s maximum of 1/2 full (0.33’ in an 8” pipe). Additionally, the existing 12” pipe would be capable of conveying sewage at a maximum depth of 0.63’, which is less than the City of Simi Valley’s maximum of 2/3 full (0.67’ in a 12” pipe). Anticipated sewage flows and depths at each of the off -site confluence points are provided in the Sewer System Master Plan.
As required by mitigation measure 4.18-1, p rior to approval of tentative tract maps, the applicant shall pay fees in accordance with Development Code Section 9 -66.050 to the City of Simi Valley.
As required by mitigation measure 4.18 -2, the applicant shall be responsible for the construction of all on -site and off-site sanitary sewer fac ilities and connections required to serve the Proposed Project. Also, as required by mitigation measure 4.18 -2, the applicant shall enter into an agreement with City of Simi Valley Department of Public Works to construct the sewer improvements and the sewer system shall be dedicated to City of Simi Valley for maintenance.
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With implementation of mitigation measures 4.18-1 and 4.18-2, the Proposed Project would not result in any new or increased impacts related to this threshold. d) Generate solid waste in excess of State or local standards, or in excess of the capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction goals? and
e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
No Substantial Change from Previous Analysis. As with the Approved Project, the Proposed Project would result in increased demand for solid waste during construction and operation. The Proposed Project does not include any new land uses that would increase solid waste generation.
Similar to the Approved Project, the Proposed Project would result in the generation of small amounts of demolition waste from the demolition of the existing golf course facilities that occupy a portion of the Project Site.
Also, the Approved Project would result in 364 residential units and a clubhouse and recreation uses at buildout that would result in ongoing generation of solid waste. As with the Approved Project, the Proposed Project would result in additional solid waste needing to be disposed of at the Simi Valley Landfill.
Solid waste for the Proposed Project would likely be disposed of at the Simi Valle Landfill.
Located northwest of the city of Simi Valley, the Simi Valley Landfill & Recycling Center (SVLRC) is a fully permitted non -hazardous municipal solid waste landfill and recycling facility that has served Ventura County for over 40 years. The SVLRC first opened in 1970 and Waste Management acquired the facility in 1983. The SVLRC is estimated to have remaining capacity of approximately 80 million cubic yards (Waste Management 2025a).
As with the Approved Project, the Proposed Project would be able to be accommodated at regional landfills, including the SVLRC. As such, the Approved Project would have less than significant impact related to solid waste. The Proposed Project would comply with all current applicable laws and regulations related to solid waste. In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to utilities and service systems that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to utilities and service systems continue t o apply; however, no new mitigation measures are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR. 1113
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3.19 WILDFIRE
3.19.1 2011 EIR
Although wildfire was not evaluated as a stand -alone topic in the 2011 EIR, t he 2011 EIR included an evaluation of the potential impacts of the Approved Project related to wildfire within Section 4.12, Public Services, of the 2011 EIR.
The 2011 EIR disclosed that the Approved Project would occur within a very high fire hazard severity zone and that the Approved Project would potentially result in increased exposure of people and buildings to wildland fires. Thus, the 2011 EIR found that the Proposed Project would result in less than significant impacts related to wildfire, including exposing people and structures to wildland fires and related hazards.
Mitigation Program
The 2011 EIR did not include mitigation measures directly related to wildfire.
3.19.2 PROPOSED PROJECT IMPACT ANALYSIS
Environmental Issues
New
Significant
Impact
More
Severe
Impacts
New Ability
to
Substantially
Reduce
Significant
Impact
No
Substantial
Change
From
Previous
Analysis
WILDFIRE– If located in or near state responsibility areas or lands classified as very high fire hazard severity zones, would the project:
a) Substantially impair an adopted emergency response plan or emergency evacuation plan?
b) Due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
c) Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment?
d) 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?
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If located in or near state responsibility areas or lands classified as very high fire hazard severity zones, would the Project:
a) Substantially impair an adopted emergency response plan or emergency evacuation plan?
No Substantial Change from Previous Analysis . The 2011 EIR determined that the Approved Project would not impair the implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan . The 2011 EIR discussed that the Proposed Project would include adequate primary and secondary access roads, which would allow for adequate access during an emergency such as a wildland fire.
The Proposed Project would result in similar impacts related to emergency evacuation as would the Approved Project given that the Proposed Project would result in similar roadway infrastructure being developed to evacuate the Project Site and because the Approved Project would not result in an increase in the number of units or individuals that would need to evacuate the Project Site when compared to the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
b) Due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
No Substantial Change from Previous Analysis . As with the Approv ed Project, the Proposed Project would occur within a very high fire hazard severity zone . The Proposed Project would potentially result in increased exposure of people and buildings to wildland fires, as would occur with the Approved Project.
To mitigate impacts related to wildfire to less than significant levels, the 2011 EIR included mitigation measures 4.12-1 through 4.12-10, which would also be applicable to the Proposed Project. With implementation of these measures, the Proposed Project would have similar impacts related to this threshold as would the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
c) Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment?
No Substantial Change from Previous Analysis. The Proposed Project would include fuel modification zones, the impacts of which have been evaluated in the 2011 EIR and in this EIR Addendum. The Proposed Project would not require the installation or maintenance of any other associated infrastructure that may result in temporary or ongoing impacts to the environment.
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In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
d) 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?
No Substantial Change from Previous Analysis . As with the Approved Project, the Proposed Project would occur within a very high fire hazard severity zone. As such, if a wildfire were to occur, there is potential for occupants, buildings, and infrastructure in the Project Site to be adversely affected by post -fire runoff, slope instability, drainage changes, and other indirect effects from wildfires.
To mitigate impacts related to wildfire to less than significant levels, the 2011 EIR included mitigation measures 4.12-1 through 4.12-10, which would also be applicable to the Proposed Project, which have been previously summarized. With implementation of these measures, the Proposed Project would have similar impacts related to this threshold as would the Approved Project.
In conclusion, the Proposed Project would not result in any new significant impacts related to this threshold.
Conclusion
The Proposed Project would not result in any new or substantially increased effects related to wildfire that were not already previously evaluated and disclosed in the 2011 EIR that was prepared for the Approved Project. Mitigation measures from the 2011 EIR relating to wildfire continue to apply; however, no new mitigation measur es are proposed as a part of the Proposed Project that would result in any new impacts that were not previously evaluated in the 2011 EIR.
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4.0 CONCLUSIONS
Based on the analysis provided in this Addendum, there is substantial evidence to determine that (1) the Proposed Project does not represent a substantial change from the previously approved project evaluated in the 2011 EIR; (2) no substantial changes have occurred with respect to the circumstances under which the Proposed Project is undertaken; and (3) the Proposed Project has not introduced new information of substantial importance that was not previously known. The Proposed Project would not have any new or substantially more severe impacts than what was evaluated in the 2011 EIR. Also, based on our analyses herein, it is our determination that the 2011 EIR , when considered in conjunction with this Addendum, provides adequate documentation, pursuant to the CEQA for the Project.
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5.0 REFERENCES
CalFire. 2025a. Fire Hazard Severity Zones (mapper). https://osfm.fire.ca.gov/what -we- do/community-wildfire-preparedness-and-mitigation/fire-hazard-severity-zones California Geological Survey. 2025a. Earthquake Zones of Required Investigation (mapper). https://maps.conservation.ca.gov/geologichazards/
Chambers Group. 2024a. Lost Canyons Development Project, 180 Lots Transfer – Summary of Biological Resources Surveys (Biological Resources Memorandum). Provided as Appendix A.
Chambers Group. 2024b. Results of the Updated Phase 1 Mature Tree Inventory Conducted for the Lost Canyons Development Project in the City of Simi Valley, Ventura County, California (Updated Tree Survey Report). Provided as Appendix B.
Chambers Group. 2024c. Lost Canyons Development Project, 180 Lots Transfer – Summary of Cultural and Paleontological Resources Studies (Cultural and Paleontological Resources Technical Memorandum). Provided as Appendix C.
Department of Toxic Substances Control. 2025a. EnviroStor. https://www.envirostor.dtsc.ca.gov/
Glenn Lukos Associates. 2025 (February). Results of the reduced footprint impact analysis for the Lost Canyons Development Project located in Simi Valley, Ventura County, California (Impact Analysis Memorandum). Provided as Appendix D.
Michael Baker International. 2025a (February). Lost Canyons 180 Lots Transfer Project – Air Quality Assessment (Air Quality Technical Memorandum). Provided as Appendix E.
Michael Baker International. 2025b (January). Lost Canyons 180 Lots Transfer Project – Energy Assessment (Energy Technical Memorandum). Provided as Appendix F.
Michael Baker International. 2025c (February). Lost Canyons 180 Lots Transfer Project – Greenhouse Gase Emissions Assessment (Greenhouse Gas Emissions Technical Memorandum). Provided as Appendix G.
Michael Baker International. 2025d (February). Lost Canyons 180 Lots Transfer Project – Noise and Vibration Assessment (Noise and Vibration Assessment Technical Memorandum). Provided as Appendix H.
Michael Baker International. 2025e (January). Lost Canyons 180 Lots Transfer Project – Transportation (Transportation Memorandum). Provided as Appendix I.
RTM Engineering Consultants. 2025a. Hydrology & Hydraulics Study for Amendment #2 for TTM 5734 (Hydrology Study). Provided as Appendix J.
1119
References
LOST CANYONS SPECIFIC PLAN PROJECT 5-2
ADDENDUM NO. 1 TO THE EIR
RTM Engineering Consultants. 2025b. Water System Master Plan. Provided as Appendix K.
RTM Engineering Consultants. 2025c. Sewer System Master Plan. Provided as Appendix L.
Simi Valley, City of. 2012a. General Plan.
https://www.simivalley.org/departments/environmental-services/planning- division/documents-applications-and-development-activity/general-plan Simi Valley, City of. Municipal Code. 2025a.
https://library.municode.com/ca/simi_valley/codes/code_of_ordinances Simi Valley, City of. Bicycle Master Plan 2008a.
https://www.simivalley.org/home/showpublisheddocument/328/637466419168 370000
United States Census Bureau. 2025. FactFinder. https://www.usa.gov/census-data United States Geological Survey. 2025 a. Interactive US Fault Map. https://www.usgs.gov/tools/interactive-us-fault-map
United States Geological Survey. 2025b. U.S. Landslide Inventory and Susceptibility Map. https://www.usgs.gov/tools/us-landslide-inventory-and-susceptibility-map Waste Management. 2025a. Simi Valley Landfill (website). https://www.wm.com/location/california/ventura-county/landfill/index.jsp Waterworks District No. 8. 2021a (June). 2020 Urban Water Management Plan. https://www.simivalley.org/home/showpublisheddocument/23836/6376928009 91770000
Waterworks District No. 8. 2021b (June). 2020 Water Shortage Contingency Plan. https://www.simivalley.org/home/showpublisheddocument/24519/6376919672 64330000
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APPENDIX A
BIOLOGICAL RESOURCES SURVEYS
1121
Lost Canyons Biological Resources
Newport Pacific Land Company
1 November 3, 2025
3151 Airway Avenue, Suite F-208
Costa Mesa, CA 92626
21091.01
Rick Nelson
Newport Pacific Land Company
100 Bayview Circle, Suite 240
Newport Beach, CA 92660
Subject: Lost Canyons Development Project, 180 Lots Transfer – Summary of Biological Resources Surveys Dear Mr. Nelson,
Chambers Group, Inc. (Chambers Group) understands that Newport Pacific Land Company (NPLC) is seeking to transfer 180 estate lots for residential development from Dry and Tapo Canyons, to the north of Lost Canyons Drive on a portion of the former golf course. This area was identified for construction impacts during the original recordation of the TTM and impacts to biological resources have been previously addressed. Chambers Group has been conducting surveys for special status plant species and least Bell’s vireo on the property since 2018 and the new proposed location for the 180 lots has been included in the survey footprints each year. A summary describing each biological resource category is presented below.
Special Status Plant Species
Surveys Conducted
• Protocol-level focused plant surveys in 2018, 2020, 2022, 2023, and 2024 Results
These results should be interpreted with the following statement taken into account in regards to California Environmental Quality Act (CEQA) protection criteria for CRPR rank ed species. As per the CNPS Rare Plant Program Committee’s 2020 Technical Memorandum, Considerations for Including CRPR 4 Plant Taxa in CEQA Biological Resource Impact Analysis, “CNPS and CDFW maintain that all CRPR 1 (plants rare, threatened, or endangered in California and elsewhere) and CRPR 2 (plants rare, threatened, or endangered in California, but more common elsewhere) taxa meet the definition of endangered, rare, or threatened under CEQA Section 15380 and must be evaluated during CEQA review. Plant taxa ranked as CRPR 4 (plants of limited distribution) generally do not currently appear to meet the criteria for listing as threatened or endangered, but CNPS and CDFW strongly recommend that these taxa be evaluated in CEQA documents. However, the basis for inclusion of CRPR 4 taxa in CEQA analyses is not as clear-cut as the basis for CRPR 1 and 2 taxa, and guidelines for determining which CRPR 4 taxa should be evaluated under CEQA have not been fully articulated.”
• Of the 18 special status plant species that were iden�fied with a poten�al for occurrence within the Phase 1 Impact Area that includes the area where the 180 lots are proposed to be located as iden�fied in the Na�ve Plant Protec�on Plan (NPMP , GLA 2015), only Catalina mariposa lily (Calochortus catalinae) and slender mariposa lily ( Calochortus clavatus var. gracilis) were recorded within the impact areas surveyed in 202 4. Impacts to these species will be mi�gated at a 1:1 ra�o as per the Na� ve Plant Mi�ga�on Plan (NPMP) through protec�on within the Conserved Lands and transfer of the 180 lots into the already proposed impact areas will not result in any addi�onal impacts or the need for addi�onal mi�ga�on.
• Three addi�onal California Rare Plant Rank (CRPR) 4 special status species, Hubby’s phacelia (Phacelia hubbyi), San Diego viguiera (Bahiopsis laciniata), and Plummer’s mariposa lily (Calochortus plummerae), were discovered during various surveying efforts from 2018 through 2023. Due to changes made to the Project boundary in 2024, the loca�ons iden�fied to contain Hubby’s phacelia and San Diego viguiera are now excluded from the Project site and were not observed in any other areas within the new Project boundary during 2024 focused plant surveys.
Plummer’s mariposa lily was observed in 2024 but is a CRPR 4 species for which CEQA protec�on is not afforded 1122
Lost Canyons Biological Resources
Newport Pacific Land Company
2 b a s e d o n a 2 0 1 2 a n a l y s i s o f t h e C R P R s t a t u s c r i t e r i a i n t h e “Rare Plant Status Review: Calochortus plummerae Proposed Rank Change from 1B.2, G3/S3 to 4.2, G4/S4” prepared by the CNPS and the California Natural Diversity Database (CNDDB). In 1994, the Plummer’s mariposa lily was placed on the CNPS Inventory (5th Edi�on) and given its CRPR 1B.2 status as many historical popula�ons had been ex�rpated, with only 58 known occurrences, and many extant popula�ons threatened or were very small. This memo explains that the reasons for a change in status from CRPR 1B.2, G3i/S3ii to CRPR 4.2, G4iii/S4iv were that, “[…] surveys have shown that Calochortus plummerae is more common than previously known” based on the 2012 reexamina�on of available popula�on records es�ma�ng well over 18,500 individuals. At this �me the Plummer’s mariposa lily, “ does not appear to be of high conserva�on concern given the following: its widespread distribu�on, high number of occurrences, the presence of some large popula�ons, and given that nearly half of its occurrences are on protected lands.”
The other 14 species iden�fied in the NPMP were not observed during the protocol-level focused plant surveys in 2018, 2020, 2022, 2023, and 2024, when each of these species would be conspicuous and iden�fiable. These species are therefore presumed absentv from the Phase 1 Impact Areas and loca�on where the 180 lots are proposed for transfer.
The transfer of the 180 lots to the loca�on iden�fied will not result in any addi�onal impacts or the need for addi�onal mi�ga�on as proposed impacts will already be mi�gated with the implementa�on of the NPMP and compliance with resource agency permits.
Least Bell’s Vireo and Other Riparian Birds
Surveys Conducted
• Protocol-level vireo surveys 2018, 2020, 2022, 2023, and 2024 Results
• Suitable arroyo willow-Fremont cotonwood habitat or other riparian habitat is not present for least Bell’s vireo (LBVI) or other special status riparian bird species in the area where the transfer of the 180 lots is proposed. There is riparian habitat north of the area where the lots are proposed to be transferred in Tapo Canyon Tributaries B and D per the Habitat Mi�ga�on and Monitoring Plan (Glenn Lukos Associates 2016), but this area will not be impacted by construc�on, and the habitat will remain in place. Incidental take of one pair and one individual LBVI has been mi�gated through proposed habitat conserva�on, enhancement, and restora�on for impacts elsewhere within the proposed development boundary and no further mi�ga�on is recommended. • The Habitat Mi�ga�on and Monitoring Plan calls for the establishment of 1.14 acres, reestablishment along with invasive species removal on 1.87 acres, and enhancement through invasive species removal of 2.96 acres of southern mixed willow riparian forest within Tapo Canyon Creek and Gillibrand Creek. Restora�on involving crea�on and enhancement of riparian habitat will occur along Tapo Canyon Creek west of Tapo Canyon Road , southern of Lost Canyons Drive. A Conserva�on Easement has been placed over this area to protect the habitat in perpetuity.
Coastal California Gnatcatcher
Surveys Conducted
• Last protocol-level surveys conducted October 2023 – March 2024 Results
• Glenn Lukos Associates, Inc. (2024) observed twelve territories/pairs within their Survey Area . None of the territories/pairs were observed north of Los Canyons Drive or within the proposed new Tenta�ve Tract Map impact limits.
• Vegeta�on within the proposed impact area where the new proposed loca�on for the 180 lots occurs was cleared prior to the nes�ng season of 2025. This vegeta�on will be maintained un�l grading can commence. 1123
Lost Canyons Biological Resources
Newport Pacific Land Company
3 Western Spadefoot Toad
Surveys Conducted
• Habitat assessment 2019 and 2023
Results
• Glenn Lukos Associates, Inc. (2015) prepared a Western Spadefoot Toad (WST) Protec�on Plan in which a mi�ga�on program would be implemented if the Project will (1) directly impact a WST occupied seasonal depression or lands within 250 feet of the occupied depression, and/or (2) directly impact lands occupied by WST adults, as described in Sec�on V.7.
• No WST were found within the new loca�on for the 180 lots during the 2019 or 2023 surveys. Surveys were conducted on mul�ple days during 2023, which was a normal rainfall year. No WST were found within the Project site during the 2023 surveys. The quality of the habitat within the Phase 1 impact areas of the Project site contains terrestrial vegeta�on, but ponding does not occur where persistent pools remain long enough to support eggs turning to tadpoles. Therefore, the Phase 1 areas do not contain suitable habitat for the WST. Furthermore, the bio- filters proposed to be impacted by Project ac�vi�es that formerly may have supported WST, no long contain suitable habitat for WST as they are no longer irrigated and the vegeta�on has transi�oned to more upland scrub; therefore, the proposed transfer of the 180 lots would not result in any impacts or the need for addi�onal mi�ga�on for WST.
Two-Striped Garter Snake
There is no habitat for two-striped garter snake present within the proposed impact areas north of Lost Canyons Drive or in the areas where the 180 lots are proposed for transfer. The area where the 180 lots are proposed for transfer consists primarily of disturbed/shortpod mustard/non-native grassland habitat as mapped in 2020.
Western Pond Turtle
There is no habitat for western pond turtle present within the proposed impact areas north of Lost Canyons Drive or in the areas where the 180 lots are proposed for transfer. The area where the 180 lots are proposed for transfer consists primarily of disturbed/shortpod mustard/non-native grassland habitat as mapped in 2020.
Burrowing Owl
Chambers Group qualified biologists conducted surveys for burrowing owl (BUOW) concurrently with the focused plant surveys throughout the Project site in April, June and August 2024. No BUOW were observed. Thirty-day pre - construction surveys with additional checks conducted 24 hours before ground disturbance and avoidance buffers will be implemented during construction if necessary.
Either all mitigation for those special status species with a potential to occur in the area proposed for development has been accomplished through existing resource agency permits and no new impacts associated with the 180-lot transfer would occur beyond those already identified for the project, or the habitat for these species is not present within the proposed area for the transfer of the 180 lots. Please let me know if you have any questions regarding this letter.
Sincerely,
CHAMBERS GROUP , INC.
Heather Clayton
Senior Biologist
[email protected]
(949) 261-5414, ext. 7241
1124
Lost Canyons Biological Resources
Newport Pacific Land Company
4 i The Global Rank (G-rank) is an indica�on of the overall condi�on and imperilment of an element throughout its global range.
It is a leter+number score that reflects a combina�on of Rarity, Threat and Trend factors, with weigh�ng being heavier on the rarity factors. The Global Ranks are assigned by NatureServe in coordina�on with the state program(s) where the element occurs. G-rank G3 means the species is vulnerable — at moderate risk of ex�nc�on or elimina�on due to a restricted range, rela�vely few popula�ons (o�en 80 or fewer), recent and widespread declines, or other factors. G-rank G4 means the species is apparently secure — uncommon but not rare; some cause for long -term concern due to declines or other factors (CNPS 2025).
ii The State Rank (S-rank) is an indica�on of the condi�on and imperilment of an element throughout its range within the state.
As with the G-rank, it is a leter+number score that reflects a combina�on of Rarity, Threat and Trend factors, weighted more heavily on rarity. The State Ranks are assigned by the CNDDB biologists using standard natural heritage methodology. S -rank S3 means the species is vulnerable — vulnerable in the state due to a restricted range, rela�vely few popula�ons (o�en 80 or fewer), recent and widespread declines, or other factors making it vulnerable to ex�rpa�on. S -rank S4 means the species is apparently secure — uncommon but not rare; some cause for long-term concern due to declines or other factors (CNPS 2025). iii The Global Rank (G-rank) is an indica�on of the overall condi�on and imperilment of an element throughout its global range.
It is a leter+number score that reflects a combina�on of Rarity, Threat and Trend factors, with weigh�ng being heavier on the rarity factors. The Global Ranks are assigned by NatureServe in coordina�on with the state program(s) where the element occurs. G-rank G3 means the species is vulnerable — at moderate risk of ex�nc�on or elimina�on due to a restricted range, rela�vely few popula�ons (o�en 80 or fewer), recent and widespread declines, or other factors. G-rank G4 means the species is apparently secure — uncommon but not rare; some cause for long -term concern due to declines or other factors (CNPS 2025).
iv The State Rank (S -rank) is an indica�on of the condi�on and imperilment of an element throughout its range within the state. As with the G-rank, it is a leter+number score that reflects a combina�on of Rarity, Threat and Trend factors, weighted more heavily on rarity. The State Ranks are assigned by the CNDDB biologists using standard natural heritage methodology. S- rank S3 means the species is vulnerable — vulnerable in the state due to a restricted range, rela�vely few popula�ons (o�en 80 or fewer), recent and widespread declines, or other factors making it vulnerable to ex�rpa�on. S-rank S4 means the species is apparently secure — uncommon but not rare; some cause for long -term concern due to declines or other factors (CNPS 2025).
v Species absence is assumed based on non- detec�on during protocol-level focused plant surveys, but species may occur at low and undetected densi�es or has the poten�al to move in later. 1125
APPENDIX B
UPDATED PHASE 1 MATURE TREE INVENTORY
1126
LOST CANYONS DEVELOPMENT PROJECT
2024 Tree Inventory
December 18, 2025
(21091.01)
John Lucarelli
Newport Pacific Land Company
100 Bayview Circle, Suite 2200
Newport Beach, CA 92660
SUBJECT: RESULTS OF THE UPDATED MATURE TREE INVENTORY CONDUCTED FOR THE LOST CANYONS
DEVELOPMENT PROJECT IN THE CITY OF SIMI VALLEY, VENTURA COUNTY, CALIFORNIA Dear Mr. Lucarelli,
The City of Simi Valley (City) has a Mature Tree Preservation Ordinance which requires an approved Tree Removal Permit prior to the removal of mature trees from a property. Grading of the Lost Canyons Development project (Project) will require the removal or relocation of a number of mature trees. The Mature Tree Preservation Ordinance also requires the replacement of all mature trees, especially oak trees in the genus Quercus, and that the value of those trees be determined by appraisal. As per Change Order 09, Tasks 4A and 4B, this tree report is an update to the findings of the 2018 mature tree inventory data submitted in August 2019 for the Phase 1 area of the Project in Simi Valley, Ventura County. This report satisfies the requirements for a Tree Removal Permit in accordance with the City of Simi Valley’s Mature Tree Preservation Ordinance (Municipal Code Section 9- 38) applies to all protected trees within City Limits.
The objective of the inventory was to update and qualify the present condition of all “mature” trees located within the approximately 211-acre grading impact area to determine the appropriate preservation, relocation, or replacement measures for each tree. This report also includes updates to exhibits to include the new boundary for the reduced Phase 1 footprint in accordance with FM 5734-1 that includes the 32 lot and the 180 lot transfers.
Any trees within this footprint that cannot be preserved in place will need to be relocated or mitigated.
Mature trees as defined by the City of Simi Valley are defined as any living tree of importance to the City of Simi Valley with a diameter of at least 5 inches (for oak trees in the genus Quercus) and 9.5 inches (for non-oak species) as measured 4.5 feet above mean natural grade (referred to as the diameter at breast height, DBH). This report presents the results of the updated 2024 Tree Inventory for trees within the Phase 1 proposed impact area.
Mature trees were mapped, measured, and tagged and their health and overall condition was evaluated. The inventory also serves to update the previous tree inventory conducted in 2018 by Chambers Group by assessing the current conditions of the site and quantifying the number of trees proposed for preservation or removal based on the current grading design, including impacts to protected tree species along Tapo Canyon Road as part of future improvements to the road.
PROJECT LOCATION AND DESCRIPTION
The Project site is bordered by Tapo Canyon Road to the east, lies north of California State Route 118, is bisected by Lost Canyons Drive, and is bordered by existing residential development to the south and west and undeveloped land to the east and north (Figure 1). The site contains substantial areas of previous ground disturbance characterized by a vacated golf course.
1127
John Lucarelli
December 18, 2025