Corona City Council
July 1, 2026

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Environmental Impact Report Addendum

sycamore woodland, mulefat scrub, SBS, as well as upland and disturbed habitats. Riparian/riverine corridors in the form of sycamore woodland, mulefat, SBS are located within Drainage Features 1, 3, and 6. Riparian and woodland habitats, including California sycamore (Platanus racemosa) woodland and mulefat (Baccharis salicifolia) scrub, are located in and adjacent to Drainage Feature 3 and Mabey Canyon Wash (Drainage Feature 6), as is SBS. Coast live oak woodland is present in the three main drainage features, Drainage Feature 1, Drainage Feature 3, and Mabey Canyon Wash (Drainage Feature 6). (L&L, 2024, p. 81) The Survey Area has been impacted by off-road vehicles, bicycles, and hikers in the more accessible areas. Dirt roads and trails crisscross the survey area, providing access for illegal trash disposal and off-road usage and grading of the Foothill Parkway Westerly Extension (FPWE). (L&L, 2024, p. 27) Consistent with the findings of the SHP EIR, implementation of the proposed Project would result in direct and indirect impacts to sensitive vegetation communities, including riparian/riverine habitats. Specifically, implementation of the proposed Project would result in the estimated direct permanent loss of approximately 151.8 acres onsite and ±5.3 offsite of native and non-native habitat, as shown on Figures 15 and 15a – c of the Project’s BRA (Technical Appendix D1) and depicted on Figure 9, Overview of Vegetation Community Impacts, and as summarized in Table 18, Project Impacts to Vegetation Communities. An additional ±1.7 acres offsite would be temporarily impacted within the proposed temporary haul road. The ±157.1 acres of permanently impacted habitat would add to the reduction in the availability of nesting, denning, and roosting sites and foraging habitats for species that utilize woodlands, shrublands, grasslands, riparian, and disturbed habitats. The ±1.7 acres offsite would be restored to jurisdictional drainage, but habitat currently is identified as disturbed. Approximately 97.6 acres of the Project site would be avoided and would remain and continue to provide habitat to local species that utilize the site. (L&L, 2024, p. 90)
Provided below is a discussion of the Project’s impacts to sensitive natural communities and riparian habitats and the mitigation measures identified to address such impacts.

Riparian/Riverine Impacts
The proposed Project would avoid ±7.74 acres (40 percent) of the ±19.30 acres of riparian/riverine habitat in the Survey Area including riparian/riverine habitats within the offsite impact areas. Included in the habitat impacts are permanent impacts to ±10.51 acres of MSHCP Riparian/Riverine area, including sycamore woodland (±0.11 acre), mulefat scrub (±0.09 acre), scale broom scrub (±3.61 acres); and impacts to upland habitats, including coast live oak woodland (±4.61 acres) and unvegetated or other upland habitats (±2.09 acres). Impacts would result from pad development, drainage improvements, and primary ingress/egress into the Project site. Additionally, ±1.13 acres of temporary impacts would occur due to the need to construct a temporary haul road between the two development areas and in one portion of the site where a detention basin would be located after development.

Avoidance of Feature 3, the largest drainage in the survey area, is not feasible because of the need for dual access points, earthwork balance, and the extensive cost of bridge development. (L&L, 2024, p. 97) Project impacts to ±4.61 acres of the ±8.57 acres of coast live oak woodland that are considered riparian/riverine habitat, as well as Project impacts to ±0.11-acre of sycamore woodland, ±0.09-acre of mulefat scrub, and ±3.61 acres of SBS represents a significant impact of the proposed Project. Although permanent impacts to ±10.51 acres

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Environmental Impact Report Addendum

Figure 9 Overview of Vegetation Community Impacts
(L&L, 2024, Figure 15)

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Environmental Impact Report Addendum

Table 18 Project Impacts to Vegetation Communities
Vegetation Community
2024
Survey Area
(acres)
Avoided
Onsite
(acres)
Project
Impacts
Onsite
(acres)
Impacts
Offsite
(acres)
Riparian/
Riverine
Impacts
(acres)
Coastal Sage Scrub

California Sagebrush Scrub 1.81 0 1.81 0.14
Ca. Sagebrush – Ca. Buckwheat
Scrub

8.81 2.22 6.59
California Buckwheat Scrub 9.25 3.13 6.12 0.01
Ca. Sagebrush – Black Sage Scrub 2.09 0.61 1.48 0.16
Black Sage Scrub 21.94 4.33 17.61 0.002
California Brittle Bush Scrub 0.09 0 0.09
Brittle Bush Scrub 2.04 0 2.04
Deerweed Scrub 0.30 0 0.30
Total CSS Alliances 46.33 10.29 36.04 0.31
Coastal Sage Scrub/Chaparral
Laurel Sumac Scrub 10.28 6.08 4.20 0.29
Bush Penstemon Scrub 41.61 18.38 23.23 0.02
Total CSS/Chaparral Alliances 51.89 24.46 27.43 0.31
Chaparral
Chamise Chaparral 21.66 13.96 7.70
Chamise-Buckwheat-Chaparral 11.05 3.45 7.60
Chamise-Black Sage Chaparral 21.06 5.72 15.34 0.03
Hoaryleaf Ceanothus Chaparral 32.38 13.91 18.47
Scrub Oak Chaparral 6.79 0.65 6.14 0.04
Scrub oak – Chamise Chaparral 13.74 5.27 8.47
Eastwood Manzanita Chaparral 3.34 2.39 0.95
Toyon Chaparral 0.31 0 0.31
Total Chaparral Alliances 110.33 45.35 64.98 0.07
Grasslands
Ca. Annual Grassland 0.43 0 0.43
Needle Grass Grassland 2.32 0.50 1.82
Total Grassland Alliances 2.75 0.5 2.25
Riparian/Riverine/Woodlands
Coast Live Oak Woodland 8.57* 0.84 7.73

0.01 4.61
Sycamore Woodland 0.27 0.16 0.11 0.11
Mulefat Scrub 0.27 0.18 0.09 0.09
Scale broom scrub 9.87 6.27 3.60 3.61
Total Riparian/Riverine/Woodlands Alliances 18.98 7.45 11.53 0.01 8.42 Developed/Disturbed/Ornamental

Eucalyptus Alliance 1.26 0.87 0.39
Pepper Alliance 1.03 0.87 0.16 6.31
Disturbed 16.83 7.81 9.02
Total Developed/Disturbed 19.12 9.55 9.57 6.31
GRAND TOTAL 249.4 97.6 151.8 7.0 8.42
*Only ±5.71 acres are within the drainage and therefore designated riverine. (L&L, 2024, Table 10)
and temporary impacts to ±1.13 acre of riparian/riverine habitat would represent a significant impact of the Project, SHP EIR Mitigation Measures BIO-MM6 and BIO-MM7 would apply, in addition to new Mitigation Measure BIO-MM23. Mitigation Measure BIO-MM6 requires the replacement of oak trees impacted by the Project at no less than a 2:1 ratio (mitigation:impact), to be planted in the undeveloped natural areas on site. SHP EIR Mitigation

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Environmental Impact Report Addendum

Measure BIO-MM7 (as modified/supplemented herein) requires mitigation for impacts to ±10.51 acres at a 2:1 ratio through offsite mitigation with the Riverside-Corona Resource Conservation District (RCRCD) or other suitable approved organization with available credits. Mitigation Measure BIO-MM23 is a new mitigation measure that is proposed to address impacts to riparian/riverine areas due to the construction of the temporary haul road, and requires the restoration of the temporary impact areas to their existing (former) condition. Implementation of the SHP EIR mitigation measures, in addition to new Mitigation Measure BIO-MM23, would reduce the Project’s impacts to riparian/riverine habitats to below a level of significance. (L&L, 2024, p. 97) Coast Live Oak Impacts
The Project would result in direct permanent impacts to ±7.73 acres of coast live oak woodlands. Of this, ±4.61 acres of coast live oak woodlands are located within riverine areas (and are discussed above under the analysis of Project impacts to riparian/riverine areas), while the remaining ±3.12 acres are located within upland areas and are not considered to comprise riparian/riverine habitat. Impacts to oaks are considered significant, but SHP EIR Mitigation Measure BIO-MM6 (as modified/ supplemented herein) requires the replacement of oak trees impacted by the Project at no less than a 2:1 ratio (mitigation:impact), to be planted in the undeveloped natural areas on site. Replacement values for the impacted oaks would be consistent with the City of Corona oak tree conservation policy, at a value of 2:1. The proposed Project also would provide for the conservation of ±0.84 acres of existing oak woodlands. Impacts to this community are considered less than significant with implementation of Mitigation Measure BIO-6 (as modified/supplemented herein). (L&L, 2024, p. 97) Scale Broom Scrub (SBS) Impacts
The Project would result in permanent impacts to ±3.61 acres of SBS. L&L mapped ±9.87 acres of SBS in the survey area, of which ±6.27 acres would not be impacted and would remain as open space that would be deed restricted from future development. CDFW ranks SBS as S3 (vulnerable) and it is considered sensitive. Impacts to SBS are considered significant, but SHP EIR Mitigation Measure BIO-MM4 (Designate Unimpacted Areas as Open Space), which has been modified herein, would conserve avoided habitat (including SBS) and prevent future impacts. SBS also would be mitigated for as riparian/riverine habitat (as discussed above). SHP EIR Mitigation Measure BIOMM7 (as modified/ supplemented herein) would reduce impacts to riparian/riverine habitat by replacing habitat at a value of 2:1. Impacts to SBS communities are adverse but would be considered a less than significant with implementation of the identified mitigation measures. (L&L, 2024, p. 97) Needle Grass Grassland Impacts
Needle grass grassland was observed in four (4) locations (generally within the center of the Survey Area) totaling ±2.32 acres, of which ±1.82 acres would be impacted by the Project. Needle grass grassland is a form of the valley and foothill grasslands identified in the MSHCP that are distributed over approximately 2,700 acres within the Plan Area on the Santa Rosa Plateau. MSHCP Core F consists of the Santa Rosa Plateau Ecological Reserve and Subunit 6: Santa Rosa Plateau and will add additional reserve lands adjacent to the Core. Therefore, conservation lands that comprise the MSHCP reserve assembly include this habitat. The Project’s impacts to this sensitive plant community would be addressed through consistency with the MSHCP and payment of the MSHCP Mitigation Fee as required pursuant to CMC Section 16.33.070. Impact to this community represents an adverse but less than significant impact, as Project impacts to this vegetation community would not regionally significant. Therefore, no additional mitigation is required. (L&L, 2024, p. 98)

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Environmental Impact Report Addendum

Coastal Sage Scrub Impacts
Included in the Project’s habitat impacts are permanent impacts to ±36.04 acres of coastal sage scrub onsite and ±0.31 acres offsite. Coastal sage scrub is identified in the MSHCP as being distributed over approximately 156,450 acres of the Plan Area . The conservation lands that comprise the MSHCP reserve assembly include this habitat; therefore, any potential impact would be addressed through compliance with the MSHCP and payment of the MSHCP Mitigation Fee as required pursuant to CMC Section 16.33.070, as this habitat has been conserved on a regional level. Impact to this vegetation communities represents an adverse but less-than-significant impact under the MSHCP. Therefore, no additional mitigation is required. (L&L, 2024, p. 98) Indirect Impacts to Sensitive Natural Communities
The Project has the potential to result in indirect impacts to sensitive natural communities due to construction activities, invasive non-native plant species, and due to human and domestic pet encroachment into the undisturbed habitats on site. These impacts are discussed below.

The use of heavy equipment, the exposure of soils, and access to/from the Project site on dirt roads during construction activities all would result in higher than usual fugitive dust and emission levels during Project clearing and grading activities, which can affect the health of local wildlife and plants. Dust particles settling directly on vegetation can affect vegetation by physical shading, thereby reducing photosynthesis, blocking leaf stomata, and/or uptake into leaf tissue. These impacts can most notably reduce vegetation growth rates. Long-term impacts are expected to be similar to what occurs under existing conditions. However, the Project would be subject to compliance with SHP EIR Mitigation Measure BIO-8 (as modified/supplemented herein), which requires the preparation and implementation of a Storm Water Pollution Prevention Plan (SWPPP) during construction activities, which would specify Best Management Practices (BMPs) to prevent discharges (e.g., siltation) from entering the jurisdictional areas on site (including riparian/riverine areas) and to reduce the amount of airborne dust. In addition, SHP EIR Mitigation Measure BIO-MM19 (as modified/ supplemented herein) requires limiting vehicle/truck speeds within the active construction site and on unpaved roads to 15 miles per hour or less, which further would reduce the potential for fugitive dust and erosion/sedimentation impacting the on-site jurisdictional areas and associated riparian/riverine habitats. With implementation of the required mitigation, Project indirect impacts due to fugitive dust and erosion/siltation affecting sensitive riparian/riverine habitats on site would be reduced to less-than-significant levels. (L&L, 2024, p. 98) A potential increase in non-native species over time, which could impact native plant species, could occur along the Project margins where newly exposed soils, not developed or landscaped, could provide fertile ground.

Invasive species to occur within the impact area and could, therefore, disperse seed to newly turned soil. Invasive and noxious weed species seed could be spread or introduced into the area by vehicles or machinery. This represents a significant indirect impact of the proposed Project. The proposed Project would be subject to compliance with SHP EIR Mitigation Measures BIO-MM5 and BIO-MM15 through BIO-MM17 (as modified/supplemented herein). In addition, in order to further preclude the potential for invasive species impacts, the Project also would be subject to compliance with new Mitigation Measure BIO-MM24. SHP EIR Mitigation Measure BIO-MM5 (as modified/supplemented here) requires the preparation and implementation of a landscape plan for the site that explicitly excludes more common cultivar forms of Coulter’s matilija poppy, including the White Cloud matilija poppy, and that excludes the species identified in MSHCP Table 6-2, Plants that

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Environmental Impact Report Addendum

Should be Avoided Adjacent to the MSHCP Conservation Area. SP EIR Mitigation Measure BIO-MM15 requires that the Project Applicant develop and provide to the City of Corona for review and comment a homeowner education plan, which would be provided to future tenants/residents to inform them about the prohibition on planting the species identified by SHP EIR Mitigation Measure BIO-MM5. SHP EIR Mitigation Measure BIO-16 requires all heavy equipment on site shall be washed prior to entering the site to prevent the spread of weedy species. SHP EIR Mitigation Measure BIO-MM17 requires that staging areas shall occur in areas that have previously been disturbed and within the Project footprint, and further requires such areas be maintained in a weed/noxious weed-free condition. New Mitigation Measure BIO-MM24 requires the Project Applicant to record Codes, Covenants, and Restrictions (CC&Rs) that explicitly prohibit the planting of the species identified by SHP EIR Mitigation Measure BIO-MM5 during the life of the Project. Implementation of the required mitigation would reduce Project indirect impacts due to invasive plant species to below a level of significance. (L&L, 2024, pp. 98-99) Human and pet encroachment into surrounding habitat areas may increase over time due to its proximity to increased occupied residential units and recreational use of the natural environment, including off-road vehicle (ORV) and pedestrian uses. Encroachment would be reduced by the incorporation of barriers between avoided areas and development (as already required by the design of the proposed Project), signage requesting that people remain on the existing trails, and Homeowner education materials. SHP EIR Mitigation Measure BIO-MM20 (as modified/supplemented herein)requires the incorporation of MSHCP measures that address this Urban/Wildlands Interface Guidelines (UWIG). Compliance with the UWIG requirements would reduce Project impacts due to human and domestic pet encroachment into on site open space areas to below a level of significance.

Conclusion
Implementation of the SHP EIR Mitigation Measures (as modified/supplemented herein) and implementation of new Mitigation Measures BIO-MM21 through BIO-MM24 would ensure that the Project’s direct and indirect impacts to sensitive vegetation communities, including riparian/riverine habitats, are reduced to below a level of significance. The mitigation measures include more stringent requirements than were identified by the SHP EIR.

It also bears noting that the Project would disturb essentially the same area as identified for disturbance by the SHP EIR, and in fact, result in less total disturbance that the Approved Project. Thus, as a general matter, the SHP EIR already anticipated and analyzed all of the impacts to biological resources that would occur from the currently proposed Project. For all these reasons, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.
c) Would the Project have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means? Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The REIR disclosed that there are no wetlands within the SHP site and as such the REIR found that the SHP would not result in impacts to federally-protected wetlands. However, the REIR found that the SHP site supports jurisdictional waters of the U.S. and riparian scrub and streambed. Thus, the REIR found that compliance with applicable regulatory requirements and implementation of the prescribed mitigation measures (BIO-MM 7 through BIOMM10) would reduce potentially significant impacts in these regards to a less than significant level. (Corona, 2016, pp. 4.C-56 through 4.C-59)

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Environmental Impact Report Addendum

EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Provided below is a discussion of the proposed Project’s potential direct and indirect impacts to wetlands and jurisdictional areas.

Project Impacts to Vernal Pools
No naturally occurring vernal pools were observed in the Survey Area. No vernal pool indicator species were observed. Soil types mapped on the site are not consistent with an alkali playa or vernal pool complex. Two areas of seasonal ponding were observed and were inundated for a short period of time during the 2024 rainy season.

CNDDB records the closest special status fairy shrimp species at more than twenty miles from the Project. Wet and dry season protocol level survey conducted in 2024 had negative findings for fairy shrimp species and no other vernal pool species was observed. The areas of ponding are believed to have resulted from an interim condition between the recent development footprint of the FPWE and the ultimate condition of the Skyline Heights Project.

These seasonal ponding areas within man-made low points will be resolved once the Skyline Heights Project infrastructure is in place. (L&L, 2024, p. 125)
Direct Impacts to Jurisdictional Drainages/Wetlands
Although the SHP EIR indicated that the SHP would result in impacts to 1.57 acres (5,232) of jurisdictional habitat subject to regulation by the United States Army Corps of Engineers (USACE) and although the USACE previously issued a 404 Permit pursuant to the federal Clean Water Act (CWA), under the current USACE guidance the drainages in the Survey Area are all ephemeral, non-Relatively Permanent Waters (RPW) that no longer are considered jurisdictional by the USACE. The area previously considered to be federal waters is now only waters of the State (RWQCB) under the Porter-Cologne Water Quality Control Act. Accordingly, the proposed Project would not result in any impacts to waters under federal jurisdiction. However, he Project would be subject to compliance with SHP Mitigation Measures BIO-MM6 and BIO-MM7, which have been modified/supplemented herein and provide more stringent mitigation for Project impacts to jurisdictional areas as compared to what previously was required by SHP EIR Mitigation Measure BIO-MM7. (L&L, 2024, pp. 83-84) The proposed Project would impact ±10.51 acres of CDFW jurisdiction (as shown on Figure 16 of the Project’s BRA, included as Technical Appendix D1), of which ±3.81 acres are CDFW wetlands and ±6.7 acres are CDFW streambeds.

The proposed Project also would impact ±1.48 acres of Santa Ana Regional Water Quality Control Board (RWQCB) jurisdiction State waters (as also depicted on BRA Figure 16). An additional ±1.13 acres of CDFW streambeds and ±0.25-acre of RWQCB state waters would be temporarily impacted within the proposed temporary haul road.

Impacts to the individual drainage features are summarized below in Table 19, Summary of Project Impacts to Jurisdictional Drainages/Wetlands. Feature details, including length, average width, and impacts to each drainage and tributary are provided in BRA Table 21 within BRA Appendix A.

The Project’s direct impacts to areas considered jurisdictional by the CDFW and/or RWQCB would be significant prior to mitigation. However, the proposed Project would be subject to compliance with the SHP EIR mitigation measures, as modified/supplemented herein. Mitigation Measure BIO-MM7 would apply, which requires mitigation for impacts to ±10.51 acres of riparian/riverine impacts at a minimum 2:1 basis (mitigation:impact), either through purchase of mitigation credits at an approved mitigation bank or through on-site mitigation. Onsite mitigation areas, if proposed, would be subject to compliance with a Habitat Mitigation and Monitoring Plan

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Environmental Impact Report Addendum

Table 19 Summary of Project Impacts to Jurisdictional Drainages/Wetlands Drainage/
Feature*
Total Combined Impacts to
CDFW Jurisdictional Areas
Breakdown of Jurisdiction
Impacts to State
(CDFW) Wetlands &
MSHCP Riparian
Impacts to State
(CDFW) Streambeds
& MSHCP Riverine
Impact to State Waters
(RWQCB)
Sq. ft. Acres Length Sq. ft. Acres Sq. ft. Acres Sq. ft. Acres Length Permanent Impacts
F-1 71,746 1.65 4,179 0 0 71,746 1.65 34,421 0.790 4,043 F-1 Offsite 6,332 0.15 131 0 0 6,332 0.15 2,600 0.060 131 F-2 0 0 0 0 0 0 0 0 0 0
F-3 346,410 7.95 11,394 158,110 3.63 188,300 4.32 24,918 0.572 10,013 F-4 0 0 0 0 0 0 0 0 0 0
F-5 12,407 0.28 2,433 0 0 12,407 0.28 2,317 0.053 1,974 F-6 21,203 0.48 497 8,061 0.18 13,142 0.30 100 0.002 112 Total 458,098 10.51 18,634 166,171 3.81ac 291,927 6.7 64,356 1.48 16,273 Temporary Impacts
F-5 3,568 0.08 222 0 0 3,568 0.08 2,206 0.05 219
F-6 Offsite 45,787 1.05 222 0 0 45,787 1.05 8,647 0.20 222 Total 49,355 1.13 444 0 0 49,355 1.13 10,853 0.25 441
*including tributaries; Difference in some totals is the result of rounding. (L&L, 2024, Table 11)
(HMMP), which would be subject to approval by the City of Corona and Wildlife Agencies. New Mitigation Measure BIO-MM23 requires the Project Applicant to restore to its current condition the areas on site that would be temporarily impacted due to the need to construct a temporary haul road. SHP EIR Mitigation Measures BIO-MM9 and BIO-MM10 (as modified/supplemented herein) also would apply, which require the Project Applicant to obtain appropriate permits from the RWQCB and CDFW for Project impacts to jurisdictional waters. Because the Project Applicant would be required to mitigate direct impacts to ±10.51 acres of riparian/riverine habitat (inclusive of impacts to 10.51 acres of CDFW jurisdictional areas and impacts to 1.48 acres of RWQCB jurisdictional areas) at a minimum ratio of 2:1, and with the restoration of the ±1.13 acres that would be temporarily impacted in association with the temporary haul road, Project impacts to jurisdictional waters subject to regulation by the CDFW and/or RWQCB would be reduced to below a level of significance. (L&L, 2024, pp. 107-111) Indirect Impacts to Jurisdictional Drainages/Wetlands
Long-term downstream impacts could occur from inadvertent discharges released from occupied residential units, park, or open space areas and roadways. This could include organic debris and chemicals from landscaped areas and household chemicals, and would represent a potentially significant indirect impact of the proposed Project.

However, the Project would be subject to SHP EIR Mitigation Measure BIO-MM8, as modified/supplemented herein, which requires the preparation and implementation of a Storm Water Pollution Prevention Plan (SWPPP) during construction activities, which would specify Best Management Practices (BMPs), including water quality basins and homeowner education, to prevent discharges from entering the jurisdictional areas on site (including riparian/riverine areas) and to reduce the amount of airborne dust. With implementation of Mitigation Measure BIO-8, the Project’s long-term indirect impacts to downstream habitat would be reduced to less-than-significant levels.

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Environmental Impact Report Addendum

Conclusion
With implementation of the mitigation measures identified in the SHP EIR, as modified/supplemented herein, the Project’s direct permanent, direct temporary, and indirect impacts to jurisdictional waters and wetlands would be reduced to less-than-significant levels, consistent with the conclusion reached by the SHP EIR. It also bears noting that the Project would disturb essentially the same area as identified for disturbance by the SHP EIR, and in fact, result in less total disturbance that the Approved Project. Thus, as a general matter, the SHP EIR already anticipated and analyzed all of the impacts to biological resources that would occur from the currently proposed Project. For all these reasons, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. d) Would the Project 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?
Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The REIR found that the SHP site does not contain suitable habitat for migratory fish; therefore, the REIR concluded that the SHP project would not have any impact on migratory fish and no mitigation is required. However, the REIR disclosed that the site contains vegetation suitable for nesting birds. Therefore, the REIR found that the SHP project may result in significant impacts on nesting bird species that are protected under the California Fish and Game Code and the Migratory Bird Treaty Act (MBTA) if removal, clearing, and/or grubbing were to occur during the general avian nesting season (January 1 to September 1). However, the REIR concluded that implementation of Mitigation Measure BIO-MM11 would reduce impacts to a less-than-significant level. The REIR also found that Impacts to regional wildlife movement would be less than significant requiring no mitigation. (Corona, 2016, pp. 4.C-59 through 4.C-60)
EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The Survey Area is bordered by dense urban development to the north and east, a few parcels of low-density residential development and open space to the west; and open space to the northwest, west and south. The survey area is north and east of MSHCP Core B (Cleveland National Forest). (L&L, 2024, p. 86)
No native wildlife nursery sites are located within the Survey Area and therefore, no significant impacts to wildlife nursery sites would occur.

The Survey Area includes native habitat that supports a variety of wildlife species and likely contributes generally to the Corona-Temecula Foothills linkage. However, it does not constitute a wildlife corridor (i.e., a piece of habitat, usually linear in nature, that connects two or more habitat patches that would otherwise be fragmented or isolated from one another), as movement on a regional scale is not confined within a specific corridor in this area. Rather, it is composed of open space at the interface with urban development and is contiguous with a large expanse of open space within MSHCP Core B and the Cleveland National Forest. Thus, wildlife currently moves freely throughout the Survey Area and surrounding areas via existing travel routes such as drainages, ridgelines, and existing dirt roads. (L&L, 2024, pp. 86-87)
It should be noted that Wardlow Wash, just offsite to the north of the survey area, was identified by BonTerra Consulting as a regional wildlife corridor that facilitates movement between the Cleveland National Forest and

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Prado Basin, as referenced by the Foothill Parkway Westerly Extension (FPWE) EIR. However, Wardlow Wash is relatively constrained by development on either side, road crossings at three locations (Paseo Grande, Serfas Club Drive, and Palisades Drive), and State Route 91, which are significant barriersto wildlife movement. Wardlow Wash would not be impacted by the proposed Project. A recognized connection between the Santa Ana Mountains and the Chino Hills area is farther to the west via Coal Canyon. The MSHCP also proposes a connection between Existing Core A (Prado Basin/Santa Ana River) with Existing Core B (Cleveland National Forest) via Constrained Linkages 1 and 2, which are also farther to the west (but east of Coal Canyon). The Survey Area also currently provides for movement on a smaller, local scale for species that live within the Survey Area. (L&L, 2024, p. 87) Upon build-out of the proposed Project, wildlife species are anticipated to continue to use open space areas adjacent (west and south) of the Project site. Thus, potential impacts to regional movement would be less than significant and no mitigation is required. Wardlow Wash would not be impacted by the Project, and the proposed Project impacts are approximately 300 feet south of the wash. The Project would not inhibit wildlife movement along the drainage; thus, impacts to regional wildlife movement are less than significant. (L&L, 2024, pp. 111-112) Although the Project site does not comprise a wildlife movement corridor, the Project site contains vegetation suitable for nesting birds, which may include species protected under the Migratory Bird Treaty Act (MBTA) and the California Fish and Game Code (CFCG). In the absence of mitigation, the Project has the potential to result in impacts to nesting migratory bird species. However, the proposed Project would be subject to compliance with SHP EIR Mitigation Measure BIO-MM11 (as modified/supplemented herein), which requires either avoidance of vegetation removal during the general avian nesting season (January 1 to September 1) when possible, and further requires a pre-construction survey in the event that construction activities must occur during the nesting season.

If active nests are found during the pre-construction survey, appropriate buffers would be established, and construction activities would be adjusted to avoid disturbance. The required mitigation would ensure that any impacts to nesting birds are minimized and reduced to a less-than-significant level. (L&L, 2024, p. 111) In addition, human presence, noise, lighting, and predator subsidies could indirectly hinder wildlife movement and could result in avoidance and abandonment of the area. However, the Project would be subject to compliance with the development standards and design guidelines specified by the proposed SHSP, applicable provisions of the CMC, and the mitigation measures identified by the SHP EIR (as supplemented/modified herein). Subsection

5.3.8 of the proposed SHSP includes the following requirement that has been included specifically to exclude human and domestic animal intrusion into the proposed open space areas on site:
“Special edge treatments shall be implemented where development areas abut open space areas, including the installation of minimum 8-foot-tall exclusion fencing in areas abutting natural open space areas, which shall be subject to review and approval by the City of Corona. No gates or other openings are allowed along rear yard walls or fences that abut biological open space areas.” (SHSP, Subsection 5.3.8) The City of Corona would review future implementing grading and building permits to ensure that the required fencing is installed at all interfaces between development areas and open space areas. In addition, after completion of construction, noise levels adjacent to the site would be increased over current conditions but would not exceed residential noise standards, and thus indirect noise impacts affecting wildlife movement would be less than significant. Development of the Project also would be subject to compliance with CMC Section 17.84.070 (Glare), which requires that “[a]ll areas of exterior lighting shall be designed to direct light downward with minimal

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spillover onto adjacent residences, sensitive land uses and open space,” which would preclude potential indirect lighting impacts affecting wildlife movement within the on-site and adjacent open space areas. Furthermore, the Project would be subject to compliance with SHP EIR Mitigation Measure BIO-MM20 (Urban/Wildlands Interface), which requires the incorporation of MSHCP measures that address the Urban/Wildlands Interface Guidelines (UWIG). Mandatory compliance with the SHP EIR mitigation measures (as supplemented/modified herein), the CMC, and the development standards and design guidelines of the proposed SHSP would ensure that the Project’s indirect impacts to wildlife movement are reduced to less-than-significant levels.

Based on the foregoing analysis, and with implementation of the SHP mitigation measures (as modified/ supplemented herein), mandatory compliance with the MSHP UWIG, compliance with the development standards and design guidelines of the proposed SHSP, and applicable provisions of the CMC, the proposed Project would not directly or indirectly interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, and the Project would not impede the use of native wildlife nursery sites. Impacts would be less than significant. It also bears noting that the Project would disturb essentially the same area as identified for disturbance by the SHP EIR, and in fact, result in less total disturbance that the Approved Project. Thus, as a general matter, the SHP EIR already anticipated and analyzed all of the impacts to biological resources that would occur from the currently proposed Project. For all these reasons, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. e) Would the Project conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
Skyline Heights Project EIR Findings: Less-than-Significant Impact. The SHP EIR found that implementation of the SHP would not conflict with any applicable plan, policy, or regulation of an agency with jurisdiction over the SHP project (including, but not limited to the General Plan and Municipal Code). The SHP EIR concluded that the impact would be less than significant. (Corona, 2015, p. 4.B-36) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Aside from the MSHCP, which is addressed separately under the analysis of Threshold f), below, the only applicable local policies or ordinances are Chapter 12.22 of the Corona Municipal Code (CMC) and the City of Corona General Plan policies related to biological resources.

Chapter 12.22 of the CMC includes the Community Forestry Program, which describes requirements regarding the planning, planting, maintenance, alteration, and removal of all trees, shrubs, and landscape materials on public property. There are no existing parkways located on the Project site, beyond the existing parkways that exist along Foothill Parkway and the western terminus of Trudy Way. Improvements proposed as part of the Project that could affect these existing parkways include proposed on-site roadway connections to Trudy Way and two proposed connections to Foothill Parkway (i.e., proposed Streets “B” and “P” on TTM 36544R1). However, with exception of the southern parkway at the Foothill Boulevard intersection with Border Avenue, which includes low-lying shrubs within the parkway, the proposed entrances into the Project site currently do not include any landscaping that would be subject to Chapter 12.22. Although the Project would result in the removal of the existing low-lying shrubs that exist along the southern edge of Foothill Boulevard as part of the construction of proposed Street “B,” TTM 36544R1 includes an overall landscape plan that identifies future landscaping requirements for the Project

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site and that implements the landscape design guidelines included in the proposed SHSP. The landscape plan calls for the planting of extensive street trees and groundcover along Street “B,” while proposed Street “P” would include trees and groundcover within both the parkways and median. In addition, the landscape plan call for the planting of street trees along the westerly extension of Trudy Way, which would result in the completion of the landscaped parkways for this portion of the roadway. The City of Corona has reviewed the Project’s proposed overall landscape plan, and has determined that the proposed landscaping for the Project would fully comply with all applicable provisions of CMC Chapter 12.22. Accordingly, and consistent with the findings of the SHP EIR, impacts due to a conflict with CMC Chapter 12.22 would not occur.

Table 4.C-4 of the SHP EIR included an analysis of the Approved Project’s consistency with the goals and policies contained within the City of Corona General Plan Environmental Resources Element. However, subsequent to certification of the SHP EIR, the City of Corona City Council adopted an update to the City’s General Plan in 2020, with the most recent amendment to the General Plan occurring in April 2024. Table 20, Project Consistency with General Plan Policies Related to Biological Resources, provides a discussion and analysis of the Project’s consistency with each of the goals and policies listed under the Biological Resources section of the Environmental Resources Element of the City’s 2020-2040 General Plan. As indicated in Table 20, with implementation of the mitigation measures presented in the SHP EIR (as supplemented/modified herein), the proposed Project would be fully consistent with the Biological Resources goals and policies contained within the General Plan Environmental Resources Element. Accordingly, Project impacts due to a conflict with General Plan goals and policies related to biological resources would be less than significant.

Table 20 Project Consistency with General Plan Policies Related to Biological Resources Goal/Policy Project Consistency
Goal ER-6: Protection, enhancement, and sustaining of
significant plant and wildlife species and habitat that exist in Corona and its Planning Area, for the long-term benefit of the natural environment and Corona residents and
visitors.

Consistent. The revisions proposed to TTM 36544 would
result in a reduction in areas planned for physical
disturbance on site from approximately 170.70 acres under the approved TTM 36544 to 151.8 acres under proposed
TTM 36544R1. As more fully documented in the Project’s
BRA and DBESP and in the analysis of Project consistency with Policies ER-6.1 through ER-6.5, with the
implementation of mitigation measures the Project would contribute to the protection, enhancement, and sustaining of significant plant and wildlife species and their habitat.

Policy ER-6.1 Support the rehabilitation and enhancement of the biological diversity, and integrity of the City’s natural resources through such means as vegetation restoration, control of alien plants and animals, landscape buffering, and natural watercourse channel restoration.

Consistent. As more fully discussed under the analyses of Thresholds b) and c), mitigation measures are proposed to reduce the Project’s impacts to sensitive plant and animal species to below a level of significant. The mitigation program includes a required 10-acre compensation parcel; the preservation of unimpacted areas on site as permanent natural open space; the salvaging of Coulter’s matilija poppy (CMP) and intermediate mariposa lily (IML) plants for replanting on or off site as compensation for Project impacts to 316 CMJ individuals and impacts to 676 IML
individuals; the translocation and seed propagation on or off site of chaparral nolina as compensation for Project

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Goal/Policy Project Consistency
impacts to ±2,180 chaparral nolina individuals; and
mitigation prohibiting the use of plants listed in Section

6.1.4 of the MSHCP.

Policy ER-6.2 Preserve the wildlife and plant species and habitats listed in Tables 4-12 and 4-13 of the Technical Background Report for the General Plan and EIR and those that may be considered by the City of Corona in the future.

Consistent. As more fully discussed under the analyses of Thresholds a) and b), no State- or federally-listed plant species were observed in the survey area during surveys conducted by L&L in 2024. However, the proposed Project would result in impacts to 18 of the 30 (60 percent)
observed Fish’s milkwort, all 342 (100 percent) paniculate tarplant, the one (100 percent) Brewer’s calandrinia, 463 of the 676 (71 percent) observed intermediate mariposa
lily (IML), 316 of the 716 (44 percent) Coulter’s matilija poppy (CMP), and ±2,180 of the estimated 5,343 (41
percent) chaparral nolina. IML, Fish’s milkwort, and CMP are covered species under the MSHCP and adequately
conserved under the Plan, and as such Project impacts to these species would be less than significant with
mandatory compliance with the MSHCP and payment of
MSHCP development fees. Brewer’s calandrinia has a wide range in California, and Project impacts to a single Brewer’s calandrinia would be considered an adverse but less-thansignificant impact. Based on the wide distribution, number of locations within western Riverside County, and known locations of this species within MSHCP conservation areas, impacts to paniculate tarplant would be considered
adverse but less than significant. Although the Project would result in impacts to ±2,180 chaparral nolina
individuals, impacts would be reduced to less-thansignificant levels with implementation of proposed new Mitigation Measure BIO-MM2. Impacts to all other plant
species on site would be less than significant.

Policy ER-6.3 Ensure that new developments and
circulation improvements demonstrate compliance with
state and federal regulations concerning the status,
location, and condition of significant and sensitive
biological species and habitats and riparian and riverine corridors. Biological surveys, as required and defined by the Western Riverside County Multiple Species Habitat
Conservation Plan, should identify potential impacts on biological resources and include mitigation measures to protect/replace resources in like kind
Consistent. Updated biological technical reports were
prepared for the proposed Project (refer to Technical
Appendices D1 and D2). As more fully discussed under the analyses of Thresholds a), b), and f), with implementation of the mitigation measures identified by the SHP EIR (as supplemented/modified herein), the proposed Project
would be fully consistent with all applicable State and federal regulations concerning biological species, their habitats, and riparian and riverine corridors. The
mitigation also would ensure full Project consistency with all applicable provisions of the MSHCP.

Policy ER-6.4 Ensure that new developments through the
development review process adhere to the Western
Riverside County Multiple Species Habitat Conservation
Plan, the Stephens’ Kangaroo Rat Habitat Conservation
Plan, and other habitat plans as appropriate to conserve Consistent. The Project site is not targeted for conservation under the Stephens’ Kangaroo Rat Habitat Conservation
Plan (SKR HCP), and the Project site falls outside of the fee area for the SKR HCP; thus, the Project has no potential to conflict with the SKR HCP (RCA, 1996, Figure 21). As

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Goal/Policy Project Consistency
biological diversity through protection of natural
communities.
indicated under the discussion and analysis of Threshold f., with mitigation the proposed Project would be fully
consistent with all applicable provisions of the MSHCP.

Policy ER-6.5 Preserve wildlife habitat of significant natural open space areas, including expanding habitat ranges,
movement corridors, and nesting sites by adhering to and implementing the core biological linkages identified in the MSHCP for parts of the Temescal Canyon Area Plan in the City. Any proposed recreational use of those areas such as trails shall be designed to not interfere with the
preservation efforts established in the MSHCP.

Consistent. As indicated under the discussion and analysis of Threshold f), the Project site is not targeted for
conservation under the MSHCP, and the Project would
accommodate a total of 182.48 acres (73% of the Project site) of natural open space and landscaped slopes. In
addition, beyond existing trails that occur on the property under existing conditions and that would not be further improved as part of the Project, all trails proposed as part of the Project would occur outside of areas proposed to be conserved as open space.

Goal ER-7 Adequate protection of biological resources and increased public awareness of their value to the
community.

Consistent. The analysis of Thresholds a) through d)
demonstrate that with mitigation, Project impacts to
biological resources would be reduced to less than
significant levels and would provide for the adequate
protection of biological resources that occur on site. The remaining portion of this goal provides direction to City of Corona staff and decision makers.

Policy ER-7.1 Require that public and private construction activities be conducted in a manner to minimize adverse impacts on natural resources and biological resources in proximity to MSHCP conservation areas and adhere to the MSHCP Guidelines pertaining to Urban/Wildlife Interface for drainage, toxics, lighting, noise, invasive barriers, and grading [MSHCP Section 6.1.4].

Consistent. As indicated under the discussion and analysis of Threshold f), the Project would be subject to compliance with the mitigation measures identified in the SHP EIR (as modified/supplemented herein), which include
requirements that implement the Urban/Wildlife Interface Guidelines (UWIG) provisions of the MSHCP.

Policy ER-7.2 Allow for publicly accessible sites that
facilitate observation of natural resources in Corona and its sphere without compromising environmental quality.

Consistent. The Project would accommodate existing trail connections within planned open space areas on site,
which would afford public access to natural resources
available on site without compromising environmental
quality.

Policy ER-7.3 Promote education programs and materials
prepared by the Western Riverside County Regional
Conservation Authority, Riverside-Corona Resource
Conservation District, and other entities that promote
awareness of biological resources conservation.

Not Applicable. Policy ER-7.3 provides direction to City staff and decision makers, and is not applicable to the proposed Project.

Goal ER-8 Protection of forest and vegetation resources in the City of Corona
Consistent. As discussed herein in Subsection 2.2, the
Project site does not contain any forestry resources under existing conditions. As discussed under the analysis of Thresholds a) and b), with implementation of the SHP EIR mitigation measures (as modified/supplemented herein),
Project impacts to vegetation communities would be
reduced to less-than-significant levels.

Policy ER-8.1 Cooperate with federal and state agencies to achieve the sustainable conservation of forest lands as a Not Applicable. Policy ER-8.1 provides direction to City staff and decision makers, and is not applicable to the proposed Project.

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means of providing open space and protecting natural
resources and MSHCP habitat.

Policy ER-8.2 Support conservation programs to reforest privately held forest lands.

Not Applicable. Policy ER-8.2 provides direction to City staff and decision makers, and is not applicable to the proposed Project.

Policy ER-8.3 Work with Riverside County to update the
Vegetation Map for Corona and the SOI areas in
cooperation with the California Department of Fish and
Wildlife, the Natural Diversity Data Base, the United States Forest Service, and other knowledgeable agencies.

Not Applicable. Policy ER-8.3 provides direction to City staff and decision makers, and is not applicable to the proposed Project.

Policy ER-8.4 Maintain and conserve superior examples of native trees (including oak trees), natural vegetation, stands of established trees, and other features for
aesthetic and water conservation purposes.

Consistent. The Project would accommodate a total of
182.48 acres (73% of the Project site) of natural open
space and landscaped slopes. In addition, and as indicated under the analysis of Thresholds a) and b), although the Project would result in direct permanent impacts to ±7.73 acres of coast live oak woodlands, the Project would be subject to compliance with SHP EIR Mitigation Measure
BIO-MM6 (as modified herein), which requires the
replacement of all impacted oak trees at a minimum 2:1
ratio.

Policy ER-8.5 Conserve the oak tree resources in the City to the extent feasible.

Consistent. As indicated under the analysis of Thresholds a) and b), although the Project would result in direct
permanent impacts to ±7.73 acres of coast live oak
woodlands, the Project would be subject to compliance
with SHP EIR Mitigation Measure BIO-MM6 (as modified
herein), which requires the replacement of all impacted oak trees at a minimum 2:1 ratio.

Goal ER-9 Protection of regional washes and waterways
and their use for recreational and open space purposes
such as trails, habitat preservation, and groundwater
recharge.

Consistent. As indicated in the discussion of Thresholds b) and c), implementation of the Project would result in
permanent impacts to ±10.51 acres and temporary impacts to ±0.11-acre of MSHCP Riparian/Riverine areas. The
Project would be subject to compliance with the mitigation measures included in the SHP EIR (as modified/
supplemented herein). Specifically, the Project would be subject to compliance with SHP EIR Mitigation Measures
BIO-MM6 (Oak Tree Replacement) and BIO-MM7
(Riparian/Riverine Mitigation), and new Mitigation
Measure BIO-MM23 (Restoration). Implementation of the
required mitigation would reduce the Project’s impacts to riparian and riverine resources to below a level so
significance.

Policy ER-9.1 Protect sensitive biological resources in the Temescal Canyon Area Plan through adherence to policies in the Western Riverside County MSHCP.

Consistent. As indicated under the discussion and analysis of Threshold f), with implementation of the mitigation
measures included in the SHP EIR (as modified/
supplemented herein), the proposed Project would be fully consistent with the Western Riverside County MSHCP.

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Goal/Policy Project Consistency
Policy ER-9.2 Conserve existing wetlands and wetland
functions and values in the Temescal Canyon Wash, Prado Basin, and the Santa Ana River with a focus on
conservation of existing riparian, woodland, coastal sage scrub, alluvial fan scrub, and open water habitats.

Not Applicable. The Project site is not located within or in close proximity to the Temescal Canyon Wash, Prado Basin, or the Santa Ana River.

Policy ER-9.3 Conserve existing known populations of least Bell’s vireo and southwestern willow flycatcher in the
Temescal Canyon Area Plan, including at Prado Basin, Santa Ana River, and Temescal Canyon Wash. Maintain existing
breeding habitat for these species at Prado Basin, Santa Ana River, and Temescal Wash where applicable to a
particular project and location.

Consistent. As documented in the Project’s BRA (Technical Appendix D1), least Bell’s vireo (LBV) was not observed during biological surveys and the riparian habitat present on the Project site does not provide suitable territorial or breeding habitat for LBV (L&L, 2024, p. 72). Additionally, the Project site does not contain any habitat suitable to support the southwestern willow flycatcher (L&L, 2024, p. 126). The remaining provisions of this policy relate to lands in close proximity to the Prado Basin, Santa Ana
River, and/or Temescal Wash and are not applicable to the proposed Project.

Policy ER-9.4 Conserve and manage suitable habitat for
species known to exist in the Temescal Canyon Area Plan of Western Riverside County’s Multiple Species Habitat
Conservation Plan.

Consistent. As indicated under the discussion and analysis of Threshold f), with implementation of the mitigation
measures included in the SHP EIR (as modified/
supplemented herein), the proposed Project would be fully consistent with the Western Riverside County MSHCP.

Policy ER-9.5 Conserve clay soils supporting sensitive plant species known to occur in the Temescal Canyon area,
including Munz’s onion, Palmer’s grappling hook, smallflowered morning glory, long-spined spineflower, threadleaved brodiaea, small-flowered microseris, and manystemmed dudleya.

Consistent. The Project site does not include any soil
groups with high clay content, with exception of
unmapped clay inclusions that are present in some areas along the ridgelines. As documented in the Project’s BRA (Technical Appendix D1), Munz’s onion Palmer’s grappling hook, small-flowered morning glory, long-spined
spineflower, thread-leaved brodiaea, small-flowered
microseris, and many-stemmed dudleya were not observed
on site and have a low probability to occur (L&L, 2024, Table 14).

Policy ER-9.6 Conserve sandy soils co-occurring with
chaparral supporting Palomar monkeyflower, known to
occur in the Temescal Canyon area.

Consistent. Palomar monkey flower has a low potential to occur on site and was not observed during field surveys conducted in 2024.

Policy ER-9.7 Conserve locations supporting California
muhly, heart-leaved pitcher sage, Hall’s monardella, and other sensitive plant species that may occur in a wide
variety of habitat types within the Temescal Canyon Area Plan.

Consistent. California muhly, heart-leaved pitcher sage, and Hall’s monardella were not observed during field
surveys conducted in 2024 and have a low potential to
occur (L&L, 2024, Table 14).

Policy ER-9.8 Provide for and maintain connection(s) from the Cleveland National Forest to Prado Basin and the Santa Ana River within Temescal Canyon, providing opportunities for offsite connections to Chino Hills State Park.

Not Applicable. Policy ER-9.8 provides direction to City staff and decision makers, and is not applicable to the proposed Project. No component of the proposed Project
would conflict with this policy.

Policy ER-9.9 Conserve upland habitat adjacent to the
Temescal Canyon Wash to augment existing upland habitat conservation in the Lake Matthews/Estelle Mountain
Reserve areas and provide for contiguous connection of
Not Applicable. Policy ER-9.9 relates to lands adjacent to the Temescal Canyon Wash and upland habitat to the east within the Lake Matthews/Estelle Mountain Reserve areas, and the Project site is not located within close proximity to

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Goal/Policy Project Consistency
upland habitat blocks from the existing reserve to Temescal Wash. Habitat conservation should focus on blocks of
existing upland habitat east of Temescal Canyon Wash
connecting to Lake Matthews/Estelle Mountain Reserve.
either the Temescal Canyon Wash or the Lake
Matthews/Estelle Mountain Reserve areas.

Policy ER-9.10 Conserve floodplain areas supporting
sensitive plant species known to occur in Temescal Canyon, including Parry’s spineflower, peninsular spineflower,
smooth tarplant, and Coulter’s matilija poppy.

Consistent. Parry’s spineflower and peninsular spineflower were not observed during field surveys conducted in 2024 and have a low potential to occur. No habitat is present on site for smooth tarplant, which has no potential to
occur. The proposed Project would result in impacts to 316 of the 716 (44 percent) Coulter’s matilija poppy (CMP)
(L&L, 2024, Table 14). As more fully discussed under the analyses of Thresholds b) and c), mitigation measures are proposed to reduce the Project’s impacts to sensitive plant species to below a level of significant. The mitigation program includes a requires a 10-acre compensation
parcel; the preservation of unimpacted areas on site as permanent natural open space (both of which support
CMP) and the salvaging of CMP plants for replanting on or off site as compensation for Project impacts to the 316 CMJ individuals. In addition, CMP are covered species
under the MSHCP and adequately conserved under the
Plan, and as such Project impacts to these species would be less than significant with mandatory compliance with the MSHCP and payment of MSHCP development fees.

Policy ER-9.11 Conserve rocky soils co-occurring with
coastal sage scrub, peninsular jumper, or chaparral
supporting Payson’s jewelflower, known to occur in the
Temescal Canyon area.

Consistent. The majority of the Project site consists of sandy loams and loamy sands, and the only portion of the Project site that contains rock outcrop complexes occurs in the extreme western portion of the Project site that is not proposed for disturbance or development as part of the
Project. Additionally, Payson’s jewelflower was not
observed during the 2024 biological surveys, and this
species has only a low potential to occur on site. (L&L, 2024, Table 14 and Figure 5)
Policy ER-9.12 Provide for and maintain a continuous
linkage along the Temescal Canyon Wash from the
southern boundary of the Temescal Canyon to the Santa
Ana River.

Not Applicable. Policy ER-9.12 provides direction to City staff and decision makers, and is not applicable to the proposed Project. Additionally, the Project site is not located in close proximity to the Temescal Canyon Wash or lands between the Temescal Canyon Wash and Santa Ana
River.

Accordingly, and based on the foregoing analysis, the proposed Project would not conflict with any applicable policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance, and impacts would be less than significant. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

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f) Would the Project conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan? Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The REIR found that the SHP site supports Riparian/Riverine Areas, which will be mitigated consistent with the requirements of the wildlife agencies via Mitigation Measures BIO-MM1, BIO-MM4 through BIO-MM6, BIO-MM7, BIO-MM9, BIOMM10, BIO-MM11, and BIO-MM14 through BIO-MM19. The REIR found that impacts to sensitive species would be addressed Mitigation Measures BIO-MM3 and BIO-MM4, and that the SHP project also would incorporate measures to meet the Western Riverside County Multiple Species Habitat Conservation Plan (MSHCP) Urban/Wildlands Interface guidelines and requirements as required by BIO-MM20; therefore, the REIR found that impacts would be less than significant. The REIR disclosed that although the SHP site is in the Burrowing Owl Survey Area and supports suitable habitat, focused surveys were negative. In accordance with the MSHCP, the REIR imposed BIO-MM12 requiring a preconstruction survey for BUOW, which the REIR found would reduce potential future impacts to BUOW to less than significant. Additionally, the REIR found that the Project Applicant would be required to pay the MSHCP development mitigation fee, which would ensure full compliance with the MSHCP. (Corona, 2016, pp. 4.C-65 through 4.C-70)
EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The only applicable Habitat Conservation Plan in the Project area is the Western Riverside County MSHCP, as the Survey Area is not located within the SKR HCP conservation area and is not within the SKR HCP fee area. Provided below is an evaluation of the Project’s consistency with MSHCP Reserve Assembly requirements, Section 6.1.2 (Protection of Species Associated with Riparian/Riverine Areas and Vernal Pools), Section 6.1.3 (Protection of Narrow Endemic Plant Species), Section 6.1.4 (Guidelines Pertaining to the Urban/Wildlands Interface [UWIG]), and Section 6.3.2 (Additional Survey Needs and Procedures).

Project Consistency with MSHCP Reserve Assembly Requirements The MSHCP defines two distinct consistency processes for development projects based on their location within the MSHCP’s coverage area, with separate processes for projects located outside of Criteria Areas and those within a Criteria Area. Criteria Areas consist of 160-acre ‘cells’ with identified conservation objectives. The Survey Area is not located within any MSHCP Criteria Cells, indicating that no portion of the Survey Area is targeted for conservation under the MSHCP. The nearest MSHCP Criteria Cell (Cell 1902) occurs approximately 0.8-mile northwest of the Project site. Accordingly, the proposed Project has no potential to conflict with the MSHCP Reserve Assembly Requirements. No impact would occur, and no mitigation measures are required.

Project Consistency with MSHCP Section 6.1.2 (Protection of Species Associated with Riparian/Riverine Areas and Vernal Pools)
As discussed in further detail under the analysis of Threshold c), no naturally occurring vernal pools were observed within the Survey Area. In addition, focused surveys for listed fairy shrimp species were negative for all species of fairy shrimp, both common and listed. Thus, the proposed Project has no potential to conflict with MSHCP Section

6.1.2 with respect to vernal pools or sensitive vernal pool species (L&L, 2024, p. 125). Impacts would not occur.

Streambed/wetland delineation studies identified ±19.3 acres of riparian/riverine area (sycamore woodland [±0.27 acre], mulefat scrub [±0.27 acre], coast live oak woodland [±5.71 acres], SBS [±9.87 acres], and streambeds

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within unvegetated or upland habitats [±3.18 acres]) in the Survey Area, including offsite impact areas. The proposed Project would result in impacts to riparian/riverine areas subject to MSHCP Section 6.1.2, including permanent impacts to ±10.51 acres riparian/riverine habitat (sycamore woodland [±0.11 acre], mulefat scrub [±0.09 acre], coast live oak woodland [±4.61 acres], SBS [±3.61 acres], and streambeds within upland habitats [±2.09 acres]). An additional ±1.13 acres of riverine habitat will be temporarily impacted. Consistent with the findings of the SHP EIR, Project impacts to riparian/riverine areas subject to MSHCP Section 6.1.2 would be significant prior to mitigation. However, the proposed Project would be subject to compliance with the SHP EIR mitigation measures, as modified/supplemented herein. SHP EIR Mitigation Measure BIO-MM7 would apply, which has been modified as part of this EIR Addendum No. 1 to require mitigation for impacts to ±10.51 acres of riparian/riverine impacts at a minimum 2:1 basis(mitigation:impact), either through purchase of mitigation credits at an approved mitigation bank or through on-site mitigation. On-site mitigation areas, if proposed, would be subject to compliance with a Habitat Mitigation and Monitoring Plan (HMMP), which would be subject to approval by the City of Corona and Wildlife Agencies. New Mitigation Measure BIO-MM23 also requires the Project Applicant to restore to its existing/former condition the areas on site that would be temporarily impacted due to the need to construct a temporary haul road. Because the Project Applicant would be required to mitigate direct impacts to ±10.51 acres of riparian/riverine habitat (inclusive of impacts to 10.51 acres of CDFW jurisdictional areas and impacts to 1.48 acres of RWQCB jurisdictional areas) at a minimum ratio of 2:1, and with the restoration of the ±1.13 acres that would be temporarily impacted in association with the temporary haul road, Project impacts to riparian/riverine areas on site would be reduced to less-than-significant levels. (L&L, 2024, pp. 124- 125)
Surveys in 2013 included protocol surveys for least Bell's vireo (LBV). LBV was not observed in the Survey Area and riparian vegetation suitable to provide territorial or breeding habitat for LBV is not present. Although some scattered willow and cottonwood species are present, vegetation diversity and density is not adequate to support the species. No suitable LBV breeding habitat is present on the site and none would be impacted. No LBV were observed on the site, and none would be impacted. The Project would have no impact on LBV, and no mitigation is required. (L&L, 2024, p. 126)
No habitat suitable to support the southwestern willow flycatcher and western yellow-billed cuckoo is present in the Survey Area and none would be impacted. The Project would have no impact on southwestern willow flycatcher and western yellow-billed cuckoo and no mitigation is required. (L&L, 2024, p. 126) Other MSHCP Section 6.1.2 species are either absent, not expected to occur, or have a low potential for occurrence, with the exception of Coulter’s matilija poppy and Fish’s milkwort (L&L, 2024, p. 126).

Coulter’s matilija poppy (CMP) was observed on the site during surveys from 2008 through 2024. Fourteen (14) locations of CMP were identified in 2008 and again in 2013 in the Survey Area. Results of the surveys in 2008 found 526 individuals. In 2013, only ±236 plants were found. Plants were found along the high flow level of active Feature 3 (unnamed drainage) and on the unpaved fire road in the middle of the Survey Area. In 2016, 37 individual CMP and groups were identified and mapped within Feature 3 and its tributaries, which is where most of the CMP were identified in 2008 and 2013. Approximately 691 plants were observed during the 2016 survey within Feature 3, which included locations not previously identified. The plants observed in 2016 were found again in 2017 and 2024. Three additional locations were observed in 2017 consisting of a total of 25 plants. Coulter’s matilija poppy is covered under the MSHCP and adequately conserved under the Plan. Implementation of the Project would

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impact these plants through loss of habitat and loss of individuals or populations within the disturbance area.

Since Coulter’s matilija poppy is covered under the MSHCP and adequately conserved under the Plan, Projectrelated impacts to Coulter’s matilija poppy would be a covered impact under the MSHCP and no mitigation is required beyond payment of the MSHCP Mitigation Fee as required pursuant to Corona Municipal Code (CMC) Section 16.33.070. (L&L, 2024, pp. 126-127)
Fish’s milkwort was identified during multiple surveys including the 2024 focused botanical surveys. A total of 25 plants were observed. Each location consisted of one or two plants, with two exceptions. Location #633 consisted of six plants and #937 consisted of five plants. All of the Fish’s milkwort identified in the Survey Area is found within Feature 3 and its tributaries and is associated with coast live oak woodland or scrub oak chaparral. Under the MSHCP, Fish’s milkwort conservation requirements have been met and this species is now adequately conserved under the Plan. Implementation of the Project would impact these plants through loss of habitat and loss of individuals or populations within the disturbance area. Since Fish’s milkwort is covered under the MSHCP and adequately conserved under the Plan, Project-related impacts to Fish’s milkwort would be a covered impact under the MSHCP and no mitigation is required beyond payment of the MSHCP Mitigation Fee as required pursuant to Corona Municipal Code (CMC) Section 16.33.070. (L&L, 2024, p. 127) Accordingly, and based on the foregoing analysis, with implementation of the SHP EIR Mitigation Measures (as modified/supplemented herein), the proposed Project would be fully consistent with MSHCP Section 6.1.2, and impacts would be reduced to less-than-significant levels.

Project Consistency with MSHCP Section 6.1.3 (Protection of Narrow Endemic Plant Species) Section 6.1.3 of the MSHCP, Protection of Narrow Endemic Plant Species, states that the MSHCP database does not provide sufficient detail to determine the extent of the presence/distribution of Narrow Endemic Plant Species within the MSHCP Plan Area. Additional surveys may be needed to gather information to determine the presence/absence of these species to ensure that appropriate conservation of these species occurs. According to mapping information available from the Western Riverside County Regional Conservation Authority (RCA), the Project site is not located in an MSHCP Section 6.1.3 designated survey area for narrow endemic plant species (RCA, n.d.). Section 6.1.3 species are either absent, not expected to occur, or have a low potential for occurrence.

The Project would have no impact on narrow endemic plant species. Therefore, the proposed Project has no potential to conflict with MSHCP Section 6.1.3, and no impacts would occur.

Project Consistency with MSHCP Section 6.1.4 (Urban/Wildlands Interface Guidelines) MSHCP Core B (Cleveland National Forest) lies immediately west and south of the Project site. Indirect impacts that result from development, including lighting, urban runoff, toxics, and domestic predators, would be minimized through Project design. Provided below is an analysis of the Project’s potential direct and indirect effects to the MSHCP Core Conservation area that could adversely affect biological resources.

Drainage
The Project incorporates streets, open channels, and natural drainage courses as well as a comprehensive system of underground storm drains to handle storm runoff from the Project site. Storm water from the Project site and offsite areas would be directed to storm drains. The design and operation of the drainage channel would be

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adequate to preclude discharge of untreated urban runoff into open space areas. The proposed development would be required to incorporate measures, including measures required through the National Pollutant Discharge Elimination System (NPDES), to ensure that quantity and quality of runoff discharged to open space area is not altered in an adverse way when compared to existing conditions. Measures would be put in place to avoid discharge of untreated surface runoff from developed and paved areas into open space areas. Storm water systems would be designed to prevent the release of toxins, chemicals, petroleum products, invasive plant materials, or other elements that might degrade or harm biological resources or ecosystem wide processes within open space areas. This would be accomplished using a variety of methods including natural detention basins, grass swales, or mechanical trapping devices. Regular maintenance would occur to ensure effective operations of runoff control systems. The Project’s proposed design also incorporates all of the requirements of SHP EIR Project Design Feature (PDF) BIO-1, which is listed at the end of this subsection. Accordingly, the proposed Project would not conflict with MSHCP Section 6.1.4 with respect to drainage. (L&L, 2024, pp. 130-131) Toxics
The proposed Project is designed to utilize natural drainage patterns for the flow of surface water. Water Quality BMPs include education, storm drain stenciling, and street sweeping in compliance with City of Corona requirements. The earthen channel would be designed to filter potential toxics in storm water prior to its discharge into open space areas. These BMPs would be implemented as part of the storm water pollution prevention measures for the Project, in accordance with all appropriate NPDES requirements. The Project would result in the additional use of hazardous materials in limited quantities associated with normal residential activity, such as cleaning products, solvents, herbicides, and insecticides. Household and other goods used by residential homes that contain toxic substances usually are low in concentration and small in amount. Residents are required to dispose of household hazardous waste, including pesticides, batteries, old paint, solvents, used oil, antifreeze, and other chemicals, at a Household Hazardous Waste Collection Facility. Also, as of February 2006, fluorescent lamps, batteries, and mercury thermostats can no longer be disposed in the trash. Furthermore, the transport, use, and disposal of hazardous materials are fully regulated by the EPA, State, Riverside County, and/or the City of Corona.

Mandatory compliance with applicable regulations would reduce the potential risk of toxic substance discharges to a level that is less than significant. Moreover, the Project would be subject to compliance with SHP EIR PDF BIO2, which is listed at the end of this subsection and specifies requirements related to BMPs to address toxics that could indirectly impact downstream receiving waters. Accordingly, the proposed Project would not conflict with MSHCP Section 6.1.4 with respect to toxics, and impacts would be less than significant. (L&L, 2024, pp. 130-131) Lighting
No nighttime construction activities are proposed as part of the Project, and as such construction-related lighting impacts affecting on- or off-site open space areas would not occur. Development of the Project would be subject to compliance with CMC Section 17.84.070 (Glare), which requires that “[a]ll areas of exterior lighting shall be designed to direct light downward with minimal spillover onto adjacent residences, sensitive land uses and open space,” which would preclude potential indirect lighting impacts affecting on- and off-site open space areas, including within MSHCP Core B. The City of Corona would review future implementing projects (i.e., building permits) to ensure compliance with CMC section 17.84.070, which would ensure that long-term operational lighting does not adversely affect the on- or off-site open space areas. Additionally, the Project would be subject to compliance with SHP EIR PDF BIO-3, which prohibits Project lighting from adversely affecting proposed open space areas on site and prohibits nighttime construction unless absolutely necessary, and further requires all

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Project lighting to comply with City of Corona requirements. As such, the Project would not conflict with the lighting provisions of MSHCP Section 6.1.4, and impacts would be less than significant.

Noise
The proposed Project incorporates landscape elements, including trees, shrubs, and groundcover, which would assist in noise reduction in native habitats adjacent to the Project. In addition, a Project-specific Noise and Vibration Analysis (NVA) was prepared for the Project and is included as Technical Appendix I to this SHP EIR Addendum No. 1. As more fully discussed under the analysis of Project noise impacts in Subsection 2.13, longterm operation of the proposed Project would not expose any surrounding land uses to daytime operational noise levels exceeding 36.8 dBA Leq or nighttime noise levels exceeding 33.9 dBA Leq, which are well below the daytime residential noise standards of 55 dBA during daytime hours and 50 dBA during nighttime hours as established by CMC Section 17.84.040 (Noise) for single-family residential land uses. In addition, the Project has been designed to implement SHP EIR PDF BIO-4, which requires the incorporation of landscaping elements at the Project perimeter with open space areas, and the analysis presented in Subsection 2.13 demonstrates that noise associated with Project operations would not expose open space areas to noise levels exceeding 65 dBA during the daytime hours and 45 DBA during the nighttime hours. Therefore, no noise created on the Project site would exceed residential noise standards. As such, the Project would be consistent with MSHCP Section 6.1.4 provisions related to noise, and impacts would be less than significant. (L&L, 2024, p. 131; UC, 2023, Tables 10-3 and 10-4) Invasive Species
Projects adjacent to the MSHCP Conservation Areas are required to avoid the use of invasive plant species in landscaping, including invasive, non-native plant species listed in Volume I, Table 6-2 of the MSHCP. Future development on site would be subject to compliance with the proposed SHSP. SHSP Table 5-3, Community Plant List, identifies a list of plant species that may be planted within the SHSP area. Based on a review of SHSP Table 5- 3, the SHSP does not include any of the prohibited plant species listed in MSHCP Volume 1, Table 6-2. In addition, SHP EIR Mitigation Measures BIO-MM5 and BIO-MM15 and (new) Mitigation Measure BIO-16 have been identified and imposed on the Project to reduce the Project’s potential to result in the introduction of invasive species on site. The Project also would be subject to compliance with SHP EIR PDF BIO-5, which is listed at the end of this subsection and requires providing future homeowners with a list of native landscaping materials allowed within the proposed development and further prohibits the use of plant species prohibited pursuant to MSHCP Table 6-

2. Implementation of SHP EIR Mitigation Measure BIO-MM5 would ensure that the Project’s landscape plans do not include any common cultivar forms of Coulter’s matilija in the plant palette, and further would ensure that the landscaping plant palette excludes those plant species identified by MSHCP Table 6-2, Plants that Should be Avoided Adjacent to the MSHCP Conservation Area. SHP EIR Mitigation Measure BIO-MM15 requires the Project Applicant to prepare and provide to future homeowners an education package informing future tenants/homeowners of the list of prohibited plant species identified by Mitigation Measure BIO-MM5. New Mitigation Measure BIO-MM24 would ensure that the Project’s Codes, Covenants, and Restrictions (CC&Rs) include a provision prohibiting the planting of any of the plant species identified by SHP EIR Mitigation Measure BIO-MM5, which would help ensure that such plant species are not planted by future homeowners/tenants.

Accordingly, with compliance with the SHSP mitigation measures and new Mitigation Measure BIO-MM24, the proposed Project would not result in the introduction of invasive species within MSHCP Core B or any of the onsite open space areas, and impacts would be reduced to less-than-significant levels. (L&L, 2024, p. 132)

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Barriers
Proposed land uses adjacent to the MSHCP Conservation Areas are required to incorporate barriers, where appropriate in individual project designs, to minimize unauthorized public access, domestic animal predation, illegal trespass or dumping in the MSHCP Conservation Areas. Such barriers may include native landscaping, rocks/boulders, fencing, walls, signage and/or other appropriate mechanisms. The proposed Project has been designed to include theme walls along Project perimeter streets adjacent to public streets, along with walls and fencing located where public view and/or important interfaces are of concern. The Project would be subject to compliance with the development standards and design guidelines specified by the proposed SHSP, applicable provisions of the CMC, and the mitigation measures identified by the SHP EIR (as supplemented/modified herein).

Subsection 5.3.8 of the proposed SHSP includes the following requirement that has been included specifically to exclude human and domestic animal intrusion into the proposed open space areas on site: (L&L, 2024, p. 132) “Special edge treatments shall be implemented where development areas abut open space areas, including the installation of minimum 6-foot-tall exclusion fencing in areas abutting natural open space areas, which shall be subject to review and approval by the City of Corona. No gates or other openings are allowed along rear yard walls or fences that abut biological open space areas.” (SHSP, Subsection 5.3.8) Thus, the Project would be required to incorporate special edge treatments designed to separate development areas from open space areas, which would serve to minimize unauthorized public access, domestic animal predation, and illegal trespass and dumping within the on- and off-site open space areas. All fencing would be permanent and maintained in perpetuity. Approval of the fencing design also would be required by the City of Corona prior to Project initiation. The Project’s proposed fencing also would implement the requirements of SHP EIR PDF BIO-6, which requires the provision of barriers to separate development areas from open space areas, measures to restrict access to the open space areas, and to preclude impacts from domestic animal predation within the open space areas. It should be noted that PDF BIO-6 has been slightly modified as part of this Addendum to require only six-foot-tall fencing per the recommendations of the Project’s biologist and in order further the City’s goal to encourage the use of the Project’s trail system by bicycles and pedestrians. Additionally, the Project would be subject to the requirements of PDF BIO-7, which requires the posting of signage at the trail entrances to inform trail users to stay on trails to avoid impacting open space areas. In addition, and as required by SHP EIR PDF BIO-8, the Project Applicant would be required to provide Homeowner Educational pamphlets to inform them of the potential impacts by uncontrolled pets on native habitats and to request residents be good stewards of the land and prevent or limit their domestic cats from being allowed to openly hunt in the avoidance area. There are no components of the proposed Project that would have the potential to conflict with the barriers provisions of MSHCP Section 6.1.4. Accordingly, potential impacts due to a conflict with MSHCP Section 6.1.4 requirements related to barriers would be less than significant. (L&L, 2024, p. 132) Grading/Land Development
The MSHCP states that manufactured slopes associated with development shall not extend into the MSHCP Conservation Areas. As depicted on the grading plan included as part of TTM 36544R1, Project grading would not extend into the off-site areas that comprise MSHCP Core B. As such, and in accordance with SHP EIR PDF BIO-9 (listed at the end of this Subsection), the Project would not conflict with the MSHCP requirements related to grading and land development, and impacts would be less than significant.

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Project Consistency with MSHCP Section 6.3.2 (Additional Survey Needs and Procedures) In accordance with Section 6.3.2 of the MSHCP, Additional Survey Needs and Procedures, additional surveys may be needed for certain species in order to achieve coverage for these species. The query of the RCA MSHCP Information Map and review of the MSHCP determined that the Study Area is located within the designated survey area for Burrowing Owl (BUOW) as depicted in Figure 6-4 within Section 6.3.2 of the MSHCP. The Project site is not located within the survey area for any other species pursuant to MSHCP Section 6.3.2. (RCA, n.d.) Burrowing owl is currently designated as a California Species of Special Concern (SSC). The burrowing owl is a grassland specialist distributed throughout western North America where it occupies open areas with short vegetation and bare ground within shrub, desert, and grassland environments. Burrowing owls use a wide variety of arid and semi-arid environments with level to gently-sloping areas characterized by open vegetation and bare ground. The western burrowing owl (Athene cunicularia ssp. hypugaea), which occurs throughout the western United States including California, rarely digs its own burrows and is instead dependent upon the presence of burrowing mammals (i.e., California ground squirrels, coyotes, and badgers) whose burrows are often used for roosting and nesting. The presence or absence of colonial mammal burrows is often a major factor that limits the presence or absence of burrowing owls. Where mammal burrows are scarce, burrowing owls have been found occupying man-made cavities, such as buried and non-functioning drainpipes, stand-pipes, and dry culverts. They also require low growth or open vegetation allowing line-of-sight observation of the surrounding habitat to forage and watch for predators. In California, the burrowing owl breeding season extends from the beginning of February through the end of August.

Under the MSHCP burrowing owl is considered an adequately conserved covered species that may still require focused surveys in certain areas as designated in Figure 6-4 of the MSHCP. The Project site occurs within the MSHCP burrowing owl survey area and a habitat assessment was conducted for the species to ensure compliance with MSHCP guidelines for the species. In accordance with the MSHCP Burrowing Owl Survey Instructions (2006), survey protocol consists of two steps, Step I – Habitat Assessment and Step II – Locating Burrows and Burrowing Owls.

A focused study conducted in 2013 on the Project site found no BUOW or BUOW sign. A habitat assessment and burrow survey conducted in 2016 found no BUOW, no BUOW sign and no suitable burrows. An updated habitat assessment and burrow survey conducted in 2024 found no BUOW, no BUOW sign and no suitable burrows. BUOW is not expected to occupy large portions of the site due to high vegetation density and steep-walled canyons. As such, burrowing owls are presumed to be absent from the Project site. Although focused surveys conducted for the proposed Project determined that the burrowing owl is absent from the Study Area, there is nonetheless a potential for the site to become occupied with burrowing owls prior to construction activities. This finding is consistent with the conclusion reached by the SHP EIR, which imposed Mitigation Measure BIO-MM12 to require pre-construction clearance surveys. The SHP EIR concluded that with implementation of Mitigation Measure BIOMM12, impacts to the BUOW would be reduced to less-than-significant levels. Mitigation Measure BIO-MM12 has been revised as part of this Addendum No. 1 to the SHP EIR in order to provide more specific requirements related to the BUOW and to fully ensure all applicable MSHCP requirements are met. Accordingly, with implementation of the revised Mitigation Measure BIO-MM12, Project impacts to the burrowing owl would be reduced to less-than-significant levels. Thus, with implementation of the required mitigation the proposed Project would not conflict with MSHCP Section 6.3.2, and impacts would be reduced to less-than-significant levels. (L&L, 2024, pp. 77, 128)

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Conclusion of MSHCP Consistency
As indicated in the preceding analysis, the proposed Project has the potential to conflict with MSHCP Section 6.1.2 (due to Project impacts to ±10.51 acres riparian/riverine habitat), MSHCP Section 6.1.4 (due to the potential for introduction of invasive species), and MSHCP Section 6.3.2 (due to potential impacts to the burrowing owl). With mandatory compliance with applicable provisions from the CMC, the development standards and design guidelines contained within the proposed SHSP, and the SHP EIR mitigation measures (as modified/supplemented herein), the proposed Project would be fully consistent with all applicable provisions of the MSHCP. Consistent with the findings reached by the SHP EIR, Project impacts due to a conflict with the MSHCP would be reduced to less than significant levels. It also bears noting that the Project would disturb essentially the same area as identified for disturbance by the SHP EIR, and in fact, result in less total disturbance that the Approved Project. Thus, as a general matter, the SHP EIR already anticipated and analyzed all of the impacts to biological resources that would occur from the currently proposed Project. For all these reasons, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

Mitigation Measures
The following mitigation measures from the SHP EIR shall apply, as modified/supplemented below, in order to reduce the Project’s potential impacts to biological resources to below a level of significance. Revisions/additions to the SHP EIR Mitigation Measures are shown below in strikeout/underline format. The revisions to the SHP EIR mitigation measure were incorporated in order to reflect current mitigation requirements for impacts to biological resources, and reflect more stringent requirements as compared to the mitigation measures included in the SHP EIR.

BIO-MM1 Biological Monitor/BMPs. The project impact areas and avoidance areas shall be flagged or fenced prior to clearing to prevent incursion into unsurveyed or avoided areas. A qualified biological monitor(s) shall monitor work activities during the initial clearing and grading phase of construction (including any ground or vegetation disturbance, demolition, fence installation, grading of existing roads, material delivery, etc.). The monitoring biologist shall ensure the flagging or fencing remains intact and no incursions into avoided areas occurs. The monitoring biologist shall examine each area of impact as the clearing/grading operations move into an uncleared native habitat area or into any area that has had a lapse in construction for more than 30 days to ensure no sensitive wildlife species are present. The biologist shall inspect debris piles, pipes, burrows, vegetation, leaf litter piles, and other potential refugia for sensitive wildlife species prior to initiation of clearing, grubbing, grading, or any other Project activity that may injure or kill sensitive wildlife species.

If wildlife is discovered, the biological monitor shall take appropriate action as defined in the mitigation measures, permit conditions, and regulations. The biological monitor may move wildlife or humanely encourage it to move out of harm’s way, if safe and feasible and permitted to do so.

Potential day roosts for pallid bat (e.g., caves, crevices, mines, hollow trees, buildings, etc.) shall be inspected by a qualified bat biologist prior to initial ground disturbance. If bats are roosting, a bat exclusion plan shall be prepared and submitted to CDFW for review prior to impacts. If a colony

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is discovered during the breeding season (March 1 -October 1), the biologist shall determine appropriate avoidance measures, including, but not limited to sound walls, buffers, and Project phasing/timing, to prevent disturbance to the colony until all young are weaned and capable of foraging independently.

Monitoring and survey activities shall be documented on a daily basis. All monitoring reports and communications shall be retained in Project files to allow review by the City of Corona, CDFW, and USFWS, if requested.

BIO-MM2 Special Status Botanical Species. Mitigation shall be provided forThe following measures shall apply to address and minimize potential impacts to Coulter’s matilija poppy, intermediate mariposa lily, and chaparral nolina to the extent feasible.  Impacts shall be minimized and avoided to the extent feasible. Prior to commencement of ground-disturbing activities (i.e., clearing and grading), Coulter’s matilija poppy and intermediate mariposa lily plants within the development footprint shall be salvaged for use in the Project area, avoidance area, or reuse in local restoration projects. In addition, a qualified botanist shall collect seeds from plants within the grading impact area during the spring or summer before grading commencement.
 Prior to commencement of ground-disturbing activities (i.e., clearing and grading), Iimpacts to chaparral nolina shall be mitigated through translocation and seed collection with propagation to an on-site or off-site preserved property acceptable to the City. Prior to any ground disturbance, the Applicant shall prepare a Chaparral Nolina Planting Plan (Plan) for chaparral nolina. The property shall be composed of habitat characteristics suitable to support chaparral nolina, including but not limited to: appropriate soils, elevation, and supporting chaparral or coastal sage scrub (or a combination thereof) habitat. The property shall be conserved via recordation of a conservation easement or deed restriction in favor of a California Department of Fish and Wildlife (CDFW)-due diligence approved local conservation entity to protect chaparral nolina on the property in perpetuity. Alternatively, the land may be transferred in fee title to a CDFW-approved local conservation entity. A management fund shall be established by the Applicant and will consist of an interest-bearing account with the amount of capital necessary to generate sufficient interest and/or income to fund all monitoring, management, and protection of the conservation area(s), including but not limited to, reasonable administrative overhead, biological monitoring, invasive species and trash removal, signage replacement and repair, law enforcement measures, long-term management reporting (as described below), and other actions designed to maintain and improve the habitat of the conserved land(s), in perpetuity.  Prior to commencement of ground-disturbing activities, a Property Analysis Record, or substantially equivalent analysis, shall be conducted by the Applicant and approved by the City to determine the management needs and costs described above, which then will be used to calculate the capital needed for the management of the fund. This management fund shall be held and managed by a CDFW-approved local conservation entity. To protect the mitigation area(s), the Project Applicant shall place appropriate signage around the perimeter of each

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site. Except for uses appropriate to a habitat conservation area, the public shall not have access to the mitigation area(s), and no activities shall be permitted within the mitigation areas, except maintenance of habitat, including the removal of nonnative plant species, trash, and debris, and the installation of native plant materials. Prior to any ground disturbance, the Applicant shall prepare a Chaparral Nolina Planting Plan (Plan) for chaparral nolina. The Plan shall require a replacement ratio of 1:1 by area, and ensure a minimum 90 percent survivorship at the end of a five-year monitoring period, which shall be verified by the monitoring biologist (minimum qualifications of the monitoring biologist are specified below).

At a minimum, the five-year plan shall include the following information:

5. a description of the existing conditions of the receiver site(s) characterizing the suitability of the site(s) for chaparral nolina, and documenting the acreage of the site,

6. a description of how the site will be preserved in perpetuity, e.g., conservation easement, deed restriction, etc., and the name of the CDFW-approved due diligence entity that will hold the easement/deed restriction, etc.,

7. qualifications of the monitoring biologist. At a minimum the monitoring biologist will possess a minimum of five-year's experience conducting habitat restoration projects in coastal sage scrub and/or chaparral habitat in Riverside County, California,

8. receiver site preparation for transplanting,

9. goals for success,

10. schedule,

11. propagation techniques,

12. transplant and seedling installation methods,

13. plant spacing,

14. performance criteria for success, including provision for control of non-native and invasive species,

15. monitoring and reporting procedures for each of the five years of the monitoring period,

16. adaptive management strategies, including a contingency plan should the site fail to meet the specified success criteria, and

17. maintenance requirements that will be reviewed and approved by the City. The Plan shall also ensure a mixture of both male and female plants.

BIO-MM3. Compensation Parcel. Prior to issuance of a grading permit, the project Applicant shall preserve a minimum of ten (10) acres (a 1:1 ratio) of natural habitat, which shall be biologically equivalent or superior to the Public/Quasi-Public (PQP) land the project site surrounds, and shall be located adjacent to USFS land. The compensation parcel shall either be:

1. Deeded in fee title to the United States Forest Service (USFS) or Western Riverside County Regional Conservation Authority (RCA) to ensure appropriate protection and permanent habitat management in perpetuity, or

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2. Conserved via recordation of a conservation easement or deed restriction in favor of a CDFWdue diligence approved local conservation entity.

BIO-MM4. Designate Unimpacted Areas as Open Space. Prior to recordation of Final Maps for each phase of the proposed development, Tthose areas of the project site not impacted by the project footprint, including Riparian/Riverine and excluding the minimum 10-acre preservation area identified in BIO-MM3, shall be conserved in perpetuity via the recordation of a conservation easement or deed restriction in favor of a CDFW-approved local conservation entity; or transferred in fee title to a CDFW-approved local conservation entity. The avoided Riparian/Riverine areas shall be conserved prior to issuance of a grading permit. The CDFW-approved local conservation entity shall manage the conservation areas to protect the long-term conservation, functions and values in-perpetuity.

BIO-MM5. Other Species to Avoid in Landscaping. Prior to issuance of grading permits, building permits, and/or road improvement plans, the Project Applicant shall prepare a landscape plan for review and approval by the City of Corona The landscape plan shall prohibit the use of The project Applicant shall add more common cultivar forms of Coulter’s matilija poppy to the list of plants to be avoided in site landscaping, including White Cloud matilija poppy. Additional non-native plants to be avoidedthat shall not be planted within any onsite mitigation or landscaping include coyote brush (Baccharis pilularis) and fourwing saltbush (Atriplex canescens). In addition, the landscape plan shall exclude those species identified in Table 6-2, Plants that Should be Avoided Adjacent to the MSHCP Conservation Area, of the Western Riverside County Multiple Species Habitat Conservation Plan (MSHCP). To ensure these non-native plants are not used in landscaping within the project site, the project Applicant shall include a list of plant species to avoid within the CC&Rs for the development. The project applicant shall also develop and distribute a suitable homeowner education package to residents / new owners covering the species to avoid.

BIO-MM6. Oak Tree Replacement. The project Applicant shall replace oak trees impacted by the project at a ratio consistent with the City of Corona oak tree conservancy policy (10.10.5), at no less than a 2:1 ratio. Replacement trees shall be located in undeveloped natural areas suitable to support these trees or in onsite mitigation areas where possible. If spacing requirements limit the number of replacement trees in these areas additional plantings may be located in landscaped areas as close to open space as feasible. All replacement trees shall be planted prior to issuance of the Certificate of Occupancy.

BIO-MM7. Riparian/Riverine. Prior to issuance of a grading permit, the project Applicant shall provide mitigation for ±10.5107 acres of Riparian/Riverine impacts at no less than a 2:1 basis, as determined through consultation with the City of Corona and wWildlife aAgencies based on their approval of the Determination of Biologically Equivalent or Superior Preservation (“DBESP”; see SHP EIR Addendum No. 1 Technical Appendix D2) that provides a functions and values analysis pursuant to the requirements of the MSHCP. The project Applicant proposes mitigation in the form of offsite mitigation with the Riverside-Corona Resource Conservation District (RCRCD) or other suitable approved organization with available credits. Currently, mitigation in banks is favored to preserve large areas of habitat where it is needed to fulfill the conservation goals of the

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MSHCP. In the event mitigation with the RCRCD is not finalized for any reason, the project Applicant shall provide equal or greater value mitigation in one or more of the following forms:
offsite acquisition and preservation, participation in an approved mitigation bank, onsite creation, offsite creation, enhancement, or reestablishment. If offsite mitigation is incorporated, the preferred choice shall be to find mitigation within or adjacent to the Santa Ana Watershed and in or adjacent to Corona if possible. In addition, some avoided resources within the open space areas shall be preserved to the extent feasible pursuant to a in an open space area and deed restrictioned or other appropriate legal mechanism to prevent future development.

If onsite mitigation is proposed as an alternative mitigation, the project Applicant shall prepare a Habitat Mitigation and Monitoring Plan (HMMP) shall be developed and provided for review and approval by local and regulatory agencies, which and shall include at a minimum the following components:
 Quantitative success criteria (vegetation cover and species richness);  Recommendations for soil preparation;
 A plant palette to include native species occurring on the site, such as coast live oak and Coulter’s matilija poppy;
 Planting methods;
 Irrigation and maintenance requirements; and
 A long-term mitigation maintenance and monitoring plan with remedial measures.

BIO-MM8. Storm Water Pollution Prevention Plan. Prior to the first ground disturbance issuance of a grading permit, the project Applicant shall prepare and implement a Storm Water Pollution Prevention Plan or for City of Corona review and approval of a Stormwater Pollution Prevention Plan (SWPPP), which shall identify all standard best management practices (BMPs) to prevent discharges from entering avoided jurisdictional drainages WoUS during construction. The required SWPPP shall at a minimum include BMPs shall that include but are not be limited to:
 Use of erosion control or sedimentation prevention methods, such as fiber rolls, sand bags, rice mats, straw wattles, or similar measures, where appropriate; and  Proper use and disposal of oil, gasoline, diesel fuel, antifreeze, and other toxic substances will be enforced.

Compliance with the City-approved SWPPP shall be required as a condition of grading permit approval, compliance with the SWPPP shall be required by bid documents issued to prospective construction contractors, and the Project construction contractors shall permit periodic inspection of the construction site by City of Corona staff or its designee to confirm compliance during all construction activities.

BIO-MM9. Regional Water Quality Control Board Permit. Prior to the issuance of a grading permit, to mitigate for the loss of 1.4857 acres and temporary loss of ±0.25-acre of State waters regulated by non-wetland WoUS due to project construction, project Applicant shall enter into an agreement with the U. S. Army Corps of Engineers (via issuance and implementation of a Nationwide permit

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or Individual permit) and with the California Santa Ana Regional Water Quality Control Board (via issuance and implementation of a Clean Water Act [CWA] Section 401 Certification) to replace permanently-impacted State waters as specified by the agreement with RWQCB affected WoUS and wetlands at a ratio specified by the U. S. Army Corps of Engineers and California Regional Water Quality Control Board, but at not less than a 2:1 basis, through offsite acquisition and preservation, participation in an approved mitigation bank, and/or on or offsite creation, enhancement, or reestablishment of WoUS State waters or a combination of these options.

Temporary impacts to RWQCB State waters shall be mitigated through on-site restoration within the temporarily impacted areas or as otherwise specified by the CWA Section 401 certification.

The exact ratio shall be based on a functions and values assessment included in the Project’s Determination of Biologically Equivalent or Superior Preservation (“DBESP”; see SHP EIR Addendum No. 1 Technical Appendix D1) and pursuant to RWQCB’s approval. Preparation of a Habitat Mitigation and Monitoring Plan (HMMP) outlining the details of the mitigation shall be required for any on-site mitigation or off-site mitigation on lands not already subject to an RWQCBapproved HMMP.

BIO-MM10. California Department of Fish and Wildlife Permit. Prior to the issuance of a grading permit, to mitigate for the loss of ±10.5107 acres of streambed and wetlands and the temporary loss of ±1.13 acres of streambed due to project construction, the project Applicant shall enter into an agreement with the California Department of Fish and Wildlife (CDFW) via issuance and implementation of a Section 1600 Streambed Alteration Agreement , Section 1600) to replace affected streambed at not less than a 2:1 basis (mitigation:impact) for permanent impacts and restoration of temporarily impacted areas to their existing/former condition, as specified by the California Department of Fish and Wildlife, through a combination of offsite acquisition and preservation, participation in an approved mitigation bank, and/or on or offsite creation, enhancement, or reestablishment of the streambed. The exact ratio shall be based on a functions and values assessment pursuant to CDFW’s approval of the required Streambed Alteration Agreement. Preparation of a Habitat Mitigation and Monitoring Plan (HMMP) outlining the details of the mitigation shall be required for on-site mitigation or off-site mitigation on lands not already subject to a CDFW-approved HMMP.

BIO-MM11. Nesting Birds. To prevent impacts to sensitive, migratory, and nesting birds (including raptors), clearing, or other work in native habitats, should shall be avoided during the critical nesting period of January 1 – September 1. If work cannot be avoided during this timeframe, a nesting bird survey shall be conducted by a qualified biologist within three (3) days prior to initiation of clearing and/or grading. A letter report documenting the clearance survey and its results shall be provided to the City of Corona prior to any disturbance to the Project site. If nesting birds are present, a nesting bird plan will shall be developed and implemented and to include appropriate measures to mitigate potential impacts, including maintaining a buffer area until fledging has occurred.

Active bird nests should shall be mapped utilizing a hand-held global positioning system (GPS) (getting as close as possible without disturbing the nest) and a buffer will be flagged around the nest (typically 300 feet for most species, 500-foot buffer for raptor nests), as determined appropriate by the biologist. Construction should not be permitted within the buffer area while

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the nest continues to be active (eggs, chicks, etc.). Once fledging has occurred no further avoidance is required.

BIO-MM12. Burrowing Owl. A pre-construction burrowing owl clearance survey shall be conducted by an experienced burrowing owl qualified biologist no more than 30 days before earth disturbance (construction). The survey will be conducted as close to the actual construction initiation date as possible. A letter report documenting the clearance survey and its results shall be provided to the City of Corona prior to any disturbance to the Project site and prior to commencement of grading activities. If owls are present, the project biologist will shall consult with local and state agencies, as appropriate, and develop a mitigation plan. Mitigation will be based on the following goals and requirements included in the MSHCP:

1. If the site contains or is part of an area supporting less than 35 acres of suitable habitat or the survey reveals that the site and the surrounding area supports fewer than three (3) pairs of burrowing owls, the onsite burrowing owls will be passively or actively relocated following accepted protocols.

2. Occupied nests shall be avoided during the nesting season (February 1 – August 31) and a buffer of 300 to 500 feet shall be employed, depending on the level of disturbance surrounding the burrow.

3. Burrow exclusion shall be utilized outside of the nesting season by installing a one-way door in burrow openings. The burrow shall be closed following verification burrows are empty (through site monitoring and scoping).

4. If the site (including adjacent areas) supports three (3) or more pairs of burrowing owls, supports greater than 35 acres of suitable habitat, and is non-contiguous with MSHCP Conservation Area lands, at least 90 percent of the area with long-term conservation value and burrowing owl pairs will be conserved onsite.

BIO-MM13. AMountain Lion Program. Prior to issuance of the first Certificate of Occupancy for each phase of development, a mountain lion (Puma concolor) program shall be developed by the project Applicant for City review and approval in an effort to reduce likelihood of human-lion conflicts.

The program shall include the following components:

1. A suitable homeowner education package for distribution to residents / new owners;

2. A suitable road sign program warning of the presence of mountain lions and the need for reduced speeds and increased caution;

3. A suitable CC&R provision limiting unsupervised outdoor pets and pet feeding practices that may encourage mountain lions to enter residential yards in search of food; and

4. A suitable mountain lion safety plan.

The Project’s CC&Rs shall include a provision specifically requiring future homeowners to comply with the requirements of the Mountain Lion Program.

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BIO-MM14. A qualified biologist shall monitor clearing and grubbing activities as they impact vegetation on the site. A qualified biologist shall inspect debris piles, pipes, burrows, vegetation, leaf litter piles, and other potential refugia for sensitive wildlife species prior to initiation of clearing, grubbing, grading, or any other project activity that may injure or kill sensitive wildlife species. If wildlife is discovered, the qualified biologist shall move it out of harm’s way or allow it to move safely out of the work area prior to initiation of project activities.

Potential day roosts for pallid bat (e.g., caves, crevices, mines, hollow trees, buildings, etc.) shall be inspected by a qualified bat biologist prior to initial ground disturbance. If bats are roosting, a bat exclusion plan shall be prepared and submitted to CDFW for review prior to impacts. If a colony is discovered during the breeding season (March-October), the biologist shall determine appropriate avoidance measures, including, but not limited to sound walls, buffers, and project phasing/timing, to prevent disturbance to the colony until all young are weaned and capable of foraging independently.

BIO-MM15. Homeowner Education Package (Invasive Species). Prior to issuance of occupancy permits, the Project Applicant shall develop for review and approval by the City of Corona, a homeowner education package providing and informing future occupants that the list of plant species identified in Mitigation Measure BIO-5 are prohibited and may not be planted on any individual lot. The homeowner education package also shall include a list of recommended non-prohibited plant species. A copy of the City-approved homeowner education package shall be provided to future owners/tenants as part of all future lease/sales agreements. Design guidelines for the proposed project shall provide the new homeowners with a list of native landscaping materials permitted within the development area. These materials have been selected for their contribution to the project theme, adaptability to local climatic and soil conditions, and for their compatibility with the unique natural environment in the area. None of the plants listed in Section 6.1.4 of the MSHCP will be utilized in the development and their use by future homeowners will be prohibited.

The MSHCP has identified invasive plants that should be removed from open space areas. This list is included in Table 6-2 of the MSHCP and in Appendix C, and shall be included in the CC&Rs prepared for the subdivision.

BIO-MM16. Invasive Vegetation Control – Heavy Equipment. All heavy equipment used onsite shall be washed, particularly the wheels and under carriage, prior to bringing it onto the project site from other construction sites to prevent the spread of weedy species.

BIO-MM17. Invasive Vegetation Control – Staging Areas. Staging areas shall be placed in areas that have been previously disturbed or have degraded habitat within the project footprint but do not show an infestation of non-native species. Staging areas shall be maintained in a weed/noxious weed-free condition.

BIO-MM18. All refuse created or brought onsite by clearing personnel or contractors shall be placed in covered containers, removed from the site daily, and disposed of properly.

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BIO-MM19. Field crews shall maintain the speed limit on posted roads and limit vehicle/truck speeds on unpaved surfaces to 15 miles per hour or less.

BIO-MM20. Urban/Wildlands Interface. Prior to issuance of grading or building permits, the City of Corona shall review the grading/building plans to ensure that measures Applicant shall ensure that the grading and building plans have incorporated the measures to meet the requirements of the The proposed project shall incorporate measures to meet MSHCP Urban/Wildlands Interface guidelines and requirements (see MSHCP Volume I, Part 2 of 2, subsection 6.1.4) with respect to These measures will address Drainage, Toxics, Lighting, Noise, Barriers, Access, Pets, and Grading/Land Development (See Section 9.5 of the BRA Report included in Appendix D to this Draft EIR).

Additional measures that have been included in this Addendum No. 1 to the SHP EIR based on current site conditions and changes to biological regulations, and area listed below.

BIO-MM21 Crotch’s Bumble Bee. In the event the Crotch’s bumble bee (Bombus crotchii) status is listed as candidate, threatened or endangered by the CDFW at the time of construction, the following measures shall be implemented.
 Clearing/ground-disturbing activities shall be prohibited from February 1 through September 30 within suitable habitat for the Crotch’s bumble bee. As part of this requirement, if construction is proposed during this period, a qualified biologist shall go out and mark all of the suitable habitat on site, which must be avoided and fencing provided around any accessible areas until at least September 30. A letter report documenting the actions performed and completion of this measure shall be provided to the City of Corona prior to any disturbance of the Project site. Construction activities may commence in areas outside of suitable habitat for the bee.
 For construction between October 1 and January 31, a pre-construction survey is required within suitable habitat to confirm that no nests occur on site. Should any nests be identified, the Project biologist shall consult with CDFW to determine if permits are required. Clearance within that portion of the property determined by the biologist to support a nest and a suitable buffer shall be avoided until consultation with the CDFW determines activities can resume or the site is no longer occupied. If the pre-construction survey identifies no nests, then construction activities may proceed as normal. A letter report documenting the actions performed and completion of this measure shall be provided to the City of Corona prior to any disturbance of the Project site. If consultation with the CDFW is required a second letter report shall be provided documenting the CDFW determination, requirements and approval prior to moving forward with construction activities on that portion of the Project site.  Pesticides considered harmful to the Crotch bumble bee shall be prohibited during construction.

BIO-MM22 Workers Environmental Awareness Program. All persons employed or otherwise working on the Project site during the vegetation clearing and grading phase of construction shall attend a

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Workers Environmental Awareness Program (WEAP) training. All workers must attend WEAP training prior to performing any work on-site. The WEAP shall consist of a presentation (either provided in person by the biological monitor or a recorded training session) that includes a discussion of the biology of the habitats and species that may be present at the site. The WEAP shall also include information about the special-status plant and wildlife species that may be present, legal protections for those species, penalties for violations, and mitigation measures. The WEAP shall include but not be limited to burrowing owl, nesting birds, and other special-status species. The WEAP shall also include information on weed control practices, appropriate trash disposal, fire prevention and procedures for smoking, spill prevention and procedures, jurisdictional waters and SWPPP, BMPs, biological monitors and compliance responsibilities, and other issues such as pets, firearms, etc. Attendance at training shall be documented and construction workers provided with a hardhat sticker. Supporting materials shall be provided to all personnel during the training program, including contact information for the biological monitor and/or other compliance personnel. Informal or formal refresher training shall be conducted as needed to maintain compliance.

BIO-MM23 Restoration. Prior to final grading inspection, temporary impact areas associated with the haul road required during site mass grading activities shall be restored to its former condition.

BIO-MM24 Invasive Species Restrictions and CC&Rs. Prior to issuance of occupancy permits, the Project Applicant shall provide the City of Corona with a copy of the Project’s Codes, Covenants, and Restrictions (CC&Rs). The Project CC&Rs shall explicitly prohibit the planting of the non-native plant species identified by Mitigation Measure BIO-5.

PDF BIO-1 Drainage. The project incorporates project streets, open channels and natural drainage courses as well as a comprehensive system of underground storm drains to handle storm runoff from the project site. Storm water from the project site and off-site areas will be directed to storm drains.

The design and operation of the drainage channel shall be adequate to preclude discharge of water into open space areas that are of lower quality or higher quality than current conditions.

The proposed development shall incorporate measures, including measures required through the NPDES requirements, to ensure that the quantity and quality of runoff discharged to the open space area is not altered in an adverse way when compared with existing conditions. In particular, measures shall be put in place to avoid discharge of untreated surface runoff from developed and paved areas into open space areas. Stormwater systems shall be designed to prevent the release of toxins, chemicals, petroleum products, exotic plant materials, or other elements that might degrade or harm biological resources or ecosystem processes within open space areas. This will be accomplished using a variety of methods including natural detention basins, grass swales, or mechanical trapping devices. Regular maintenance shall occur to ensure effective operations of runoff control systems.

PDF BIO-2 Toxics. The proposed project is designed to utilize natural drainage patterns for the flow of surface water. Water Quality Best Management Practices (BMPs) include education, storm drain stenciling, and street sweeping in compliance with the City of Corona’s requirements. The earthen channel shall be signed to filter potential toxics in the storm water prior to its discharge into open

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space areas. These BMPs will be implemented as part of the storm water pollution prevention measures for the project, in accordance with all appropriate NPDES requirements. The project would result in the additional use of hazardous materials in limited quantities associated with normal residential use such as cleaning products, solvents, herbicides, and insecticides. However, compliance with regulations will reduce the potential risk of hazardous material exposure to a level that is less than significant. An information pamphlet has been prepared for each homeowner regarding the use of toxics.

PDF BIO-3 Lighting. Outdoor lighting of residences will be designed so that all direct beams would be confined to dwelling sites. Project lighting will not intrude into the open space conservation areas.

Street lighting, parking lot lighting, and other project-related illumination sources will be positioned, directed, and shielded so as to avoid “light spill” into the conserved areas. The proposed project will avoid any night lighting adjacent to the open space areas. Night lighting will not be used during the course of construction unless absolutely necessary. If necessary, the lights will be directed and shielded to minimize lighting of the surrounding habitat. The level of off-site lighting and lighting fixtures would comply with the applicable requirements and policies of the City of Corona.

PDF BIO-4 Noise. The proposed project incorporates landscape elements including trees, shrubs, and groundcover, which will assist in noise reduction on the project site. In addition, a noise analysis prepared for the project found that no proposed on-site or surrounding sensitive land uses would experience long-term noise levels in excess of 65 dBA during the daytime hours under build-out of the proposed project. This daytime noise level would not result in exterior nighttime levels greater than 45 dBA. Therefore, no noise created on the project site would exceed residential noise standards.

PDF BIO-5 Invasives. Exotic Vegetation Control – Design guidelines for the project will provide the homeowners with a list of native landscaping materials permitted within the project site. These materials have been selected for their contribution to the project theme, adaptability to local climatic and soil conditions, and for their compatibility with the unique natural environment in the project site. The MSHCP has identified exotic invasive plants that should be areas avoided adjacent to the MSHCP Conservation Area in Table 6-2, Section 6.1.4 of the MSHCP; none of these plants will be utilized for the proposed project and their use by future homeowners will be prohibited.

PDF BIO-6 Barriers. The proposed project will include theme walls along project perimeter streets adjacent to public streets, and will include walls and fencing located where public view and/or important interfaces are of concern. The proposed project will incorporate special edge treatments designed to separate development areas from open space areas. These areas of native landscaping and fencing will serve to minimize unauthorized public access, domestic animals predation, and illegal trespass and dumping. Exclusion fencing will be permanently placed where development abuts avoided and adjacent open space areas. The exclusion fence will be a minimum of eight six feet in height and will be installed and maintained for the purposed of controlling human and pet access (cats and dogs) into the open space area and be in compliance with MSHCP requirements. The

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fencing will be permanent and will be maintained in perpetuity. Approval of the fencing design will be required by the City of Corona prior to project initiation.

PDF BIO-7 Access. Access points between native habitats and the project development will be posted with signage requesting residents to stay on the trails and not to disturb habitat. Yard fencing with no back gate will reduce access to native habitats adjacent to the project.

PDF BIO-8 Pets. Uncontrolled pets, feral dogs and cats can predate on native wildlife species. Appropriate signage will be posted requesting residents leash their pets. Homeowner Educational pamphlets will be used to inform them of the potential impacts by uncontrolled pets on native habitats and to request residents be good stewards of the land and prevent or limit their domestic cats from being allowed to openly hunt in the avoidance area.

PDF BIO-9 Grading/Land Development. All manufactured slopes associated with site development will be within the project site and there will be no impact to the MSHCP Conservation Area. All manufactured slopes that abut the natural open space will be retained as open space buffer zones.

All manufactured slopes and areas disturbed by construction of these slopes will be revegetated with appropriate non-invasive buffer species during project construction.

2.5 Cultural Resources
New
Significant
Impact
More
Severe
Impacts
New Ability to
Substantially Reduce
Significant Impact
No Substantial
Change from
Previous Analysis
Would the Project:
a. Cause a substantial adverse change in the
significance of a historical resource as
defined in Section 15064.5 of the State
CEQA Guidelines?
☐ ☐ ☐ ☒
b. Cause a substantial adverse change in the
significance of an archaeological resource
pursuant to State CEQA Guidelines Section
15064.5?
☐ ☐ ☐ ☒
c. Directly or indirectly destroy a unique
paleontological resource or site or unique
geologic feature?
☐ ☐ ☐ ☒
d. Disturb any human remains, including those
interred outside of formal cemeteries? ☐ ☐ ☐ ☒
e. Conflict with an applicable plan, policy, or
regulation adopted for purposes of avoiding
or mitigating physical impacts associated
with cultural resources?
☐ ☐ ☐ ☒

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ENVIRONMENTAL ANALYSIS
In order to evaluate the proposed Project’s potential impacts to cultural and paleontological resources, two Project-specific technical studies were prepared for the Project by BFSA Environmental Services (herein, “BFSA”).

The first report is a Cultural Resources Assessment (herein, “CRA”) titled, "A Phase I Cultural Resources Assessment for the Skyline Heights Project," dated October 26, 2023, and included as Technical Appendix E to this EIR Addendum (BFSA, 2023a). The second report addresses paleontological resources, is titled, “Paleontological Sensitivity Update and Revised Monitoring Recommendations for the Skyline Heights Project, City of Corona, Riverside County, California (Sch. No. 2014021003)” (herein, “PRA”) is dated October 26, 2023, and is included as Technical Appendix F to this EIR Addendum (BFSA, 2023b). a) Would the Project cause a substantial adverse change in the significance of a historical resource as defined in Section 15064.5 of the State CEQA Guidelines? Skyline Heights Project EIR Findings: No Impact. The SHP EIR found that no historic resources are located on the SHP site. As such, the SHP EIR found that there is no potential for the SHP to cause a substantial adverse change in the significance of a historical resource as defined in Section 15064.5 of the CEQA Guidelines. The SHP EIR concluded that no impact would occur. (Corona, 2015, p. 4.D-14) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. As discussed in further detail in Subsection 4.2 of the Project’s CRA (Technical Appendix E), in April and May of 2013, LSA (2014) completed a Phase I Cultural Resources Assessment of the Project site. The survey resulted in the relocation of the Sky Ranch site (identified as Site P-33-016976) and the identification of an erosion control system composed of approximately 30 circa 1940s to 1950s automobiles buried on their side (identified as Site P-33-029450). The Sky Ranch was previously identified by LSA in 2006 and recorded in 2008 by SWCA. SWCA recorded a “small masonry shed, a metal water tank, a concrete residence and aircraft hangar foundations, arroyo stone walls and bridge, and other remnant landscaping features. While the majority of the site was determined to be ineligible for listing on the California Register of Historical Resources (CRHR) according to CEQA criteria, SWCA evaluated the bridge feature as eligible for listing on the CRHR as a separate property. Although ground visibility was poor, LSA relocated all of the features identified by SWCA and noted that the site appeared to be generally unchanged from the previous survey conducted in 2008 by SWCA. While the automobile erosion control system was noted, the feature was not formally recorded, as “its origin and date of deposition could not be determined…” As a result, no previouslyunrecorded cultural resources were identified within the Project area as a result of the 2013 Cultural Resources assessment and LSA recommended monitoring of all ground-disturbing activities within the project area “on a part-time (spot-check) basis.” (BFSA, 2023a, p. 4.0-16) An updated site reconnaissance was conducted for the Project site by BFSA in June 2023. The archaeological survey of the property conducted by BFSA was a reconnaissance consisting of a series of parallel survey transects spaced at 10-meter intervals. Generally, visibility throughout the property was very poor, with just five percent of the ground surface visible. A small portion of the property was developed with paved roads and dirt bike trails (approximately five percent). Vegetation observed throughout the property included primarily inland sage scrub and riparian communities, with a small quantity of eucalyptus noted. The cultural resources survey resulted in the relocation of a portion of the Sky Ranch site and the erosion control feature. No additional prehistoric or historic archaeological resources were identified during the survey conducted by BFSA. (BFSA, 2023a, p. 4.0-16)

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The Sky Ranch site (Site P-33-016976) was relocated and identified in very poor condition. Of the recorded features, the hangar foundations, a demolished structure foundation, and an arroyo stone wall were identified (Plates 4.2–3 through 4.2–6). No other features, including the CRHR-eligible bridge feature, could be relocated. As a result of the survey, the previous determination of Site P-33-016976 as being ineligible for listing on the CRHR was confirmed. (BFSA, 2023a, p. 4.0-16)
In addition to the Sky Ranch site features, the erosion control feature, consisting of the circa 1940s to 1950s automobiles, was relocated by BFSA. Aerial photographs indicate that the feature likely was created after 1980.

However, given that the approximate manufacture dates of the automobiles are older than 50 years in age, they were recorded as a new resource (Site P-33-029450). While Site P-33-029450 is associated with the property, it does not appear to be directly linked to it, since the property was vacant at the time it was created. Therefore, a firm connection between Site P-33-029450 and Site P-33-016976 could not be established. Site P-33-029450 is not associated with any individuals or events important to local, State, or national history. Further, this feature could not be tied to any great architectural works or the work of a master architect, artist, or builder. In addition, the automobiles are severely rusted, crushed, and demolished, lacking all original integrity. Therefore, the erosion control feature consisting of circa 1940s to 1950s automobiles does not constitute a significant historical resource according to CEQA criteria and is not eligible for listing on the CRHR. (BFSA, 2023a, p. 4.0-21) In summary, although both Site P-33-029450 nor Site P-33-016976 were relocated during the 2023 site reconnaissance conducted by BFSA, these features were determined to be ineligible for listing on the CRHR. In addition, no other historical resources were identified on the Project site during the 2023 or prior surveys.

Accordingly, and consistent with the conclusion reached by the SHP EIR, implementation of the proposed Project would not result in any impacts to any known historical resources, and impacts would be less than significant.

Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. b) Would the Project cause a substantial adverse change in the significance of an archaeological resource pursuant to State CEQA Guidelines Section 15064.5?
Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that implementation of the SHP would not cause a substantial adverse change in the significance of a known archaeological resources pursuant to Section 15064.5 of the CEQA Guidelines. However, the SHP found that there is a potential for the SHP project to impact previously undiscovered archaeological resources during construction activities. The SHP EIR imposed Mitigation Measure CR-1, which the SHP EIR found would reduce impacts to below a level of significance. (Corona, 2015, pp. 4.D-15 to 4.D-16) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. As noted under the analysis of Threshold a), the 2023 archaeological survey conducted by BFSA resulted in the relocation of the Sky Ranch property site (Site P-33-016976) and the erosion control feature consisting of 1940s to 1950s vehicles (Site P-33- 029450). However, the previously-recorded Sky Ranch Arroyo Bridge feature that was recommended as eligible for the CRHR could not be relocated. The Sky Ranch property was found in poor condition and was previously determined as not eligible for the CRHR; BFSA concurs with this determination. The row of 1940s to 1950s vehicles was recorded as a new site, Site P-33-029450, and was evaluated as not eligible for the CRHR according to CEQA

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criteria. As designed, the CRHR-eligible Sky Ranch bridge feature would not be impacted by the proposed development. In addition, no previously-unrecorded prehistoric cultural resources were identified during the survey. Therefore, and consistent with the findings reached by the SHP EIR, the proposed Project would not impact any significant archaeological resources as defined by CEQA Guidelines Section 15064.5(a), and no impacts to known archaeological resources would occur with implementation of the Project. (BFSA, 2023a, p. 5.0-1) Although impacts to previously-discovered archaeological resources would not occur, the Project area is located in an area of high cultural resources sensitivity, given the access to multiple natural sources of water throughout the property and the ecological setting (plants and animals available) of the property. The ground surface visibility of the property was very poor, with only five percent of the ground surface visible at the time of the survey.

Therefore, and consistent with the findings of the SHP EIR, the potential exists that buried prehistoric cultural deposits may be present within the development envelope. The proposed Project would be subject to compliance with the mitigation measures identified by the SHP EIR (as modified/supplemented herein). Specifically, grading and ground-disturbing activities would be monitored by an archaeological monitor and Native American monitor, as required by SHP EIR Mitigation Measure CR-1. SHP EIR Mitigation Measure CR-1 further requires appropriate treatment of any newly-discovered cultural resources, including the development of avoidance strategies, capping with fill material, or mitigation of impacts through data recovery programs such as excavation or detailed documentation. Such monitoring also would be required to be conducted pursuant to a Treatment Agreement between affected Tribes. Consistent with the conclusion reached by the SHP EIR, implementation of Mitigation Measure CR-1 would reduce the Project’s potential impacts to previously-undiscovered cultural resources to below a level of significance. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. (BFSA, 2023a, p. 5.0-1)
c) Would the Project directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that implementation of the SHP could directly impact paleontological resources during construction activities. The SHP EIR found that this potentially significant impact would be reduced to a less-than-significant level with implementation of SHP EIR Mitigation Measures CR-2 to CR-4. (Corona, 2015, p. 4.D-16) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. An updated paleontological resource assessment report for the SHP was prepared in support of the SHP EIR by LSA in 2013 (herein, “2013 PRA”), which was included in Appendix E to the SHP EIR. In the 2013 PRA, three geologic formations present at the project were found to have a high potential to yield significant nonrenewable paleontological resources during earth disturbance activities. The 2013 PRA recommended that a Paleontological Resources Impact Mitigation Program (PRIMP) be implemented to reduce potential impacts to paleontological resources during earth disturbance activities. In a 2014 supplementary study prepared by LSA and updating their 2013 assessment (herein, “2014 PRA Update”), LSA revised their 2013 PRA, adding several parcels to the analysis. With the addition of the new parcels, LSA expanded their previous record search, concluded that four mapped geologic units (1:
undifferentiated Williams and Ladd Formations; 2: Baker Canyon Conglomerate Member of the Ladd Formation; 3: Ladd Formation; 4: Silverado Formation) are potentially fossiliferous, and recommended that a PRIMP be implemented. The 2014 PRA Update indicated the Pleistocene and Holocene-aged deposits mapped at the SHP

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site “are generally considered too coarse or too young to contain significant vertebrate fossils in a meaningful stratigraphic context,” but the 2014 PRA Update did not provide guidance for their treatment, should they be encountered during excavation or grading activities. (BFSA, 2023b, pp. 1-2) The City of Corona adopted its current General Plan in 2020 and concurrently certified an EIR. General Plan Figure HR-1 and Figure 5.7-6 of the General Plan EIR depict a city-wide map presenting levels of paleontological sensitivity assigned to geologic formations. The map is the result of a tabulation of every mapped geologic formation within Corona and the Corona sphere of influence, with a rating of paleontological sensitivity assigned to each formation.

Ratings of None, Low, Low-to-High, High, and Unknown are provided. Based on these classifications, Table 21, Project Site Paleontological Sensitivity, summarizes the paleontological sensitivity of the Project site.

As shown in Table 21, the paleontological sensitivity geologic formations within the on-site drainages are classified as having “Low-to-High” paleontological sensitivity, while the majority of the property is classified as having a “High” sensitivity for containing paleontological resources. The General Plan identifies a “low-to-high” sensitivity as where “[s]ome sedimentary deposits are too young to preserve fossils at the surface or shallow subsurface but may preserve fossils at greater depth or overlie older units that have high paleontological sensitivity.” A “high” sensitivity is defined as “…. geologic formations that are known to preserve abundant or scientifically significant fossils, therefore giving them high sensitivity to paleontological resources.” (Corona, 2020, p. HR-16) Table 21 Project Site Paleontological Sensitivity
Geologic Formation Geologic Age Paleontological Sensitivity Young alluvial fan deposits Holocene and late Pleistocene Low-to-High Young alluvial (axial) channel deposits Holocene and late Pleistocene Low-to-High Young landslide deposits Holocene and late Pleistocene Low-to-High Very old alluvial fan deposits Early Pleistocene High
Silverado Formation Paleocene High
Williams and Ladd Formations,
undifferentiated
Upper Cretaceous High
Ladd Formation Upper Cretaceous High
Ladd Fm., Baker Canyon Conglomerate
Member
Upper Cretaceous High
(BFSA, 2023b, p. 5)
Based on the Project’s proposed grading plan, it is not anticipated that the Project would require grading at depths that may potentially encounter paleontological resources within the portions of the Project site that are considered to have a “Low-to-High” sensitivity for paleontological resources. As such, and consistent with the conclusion reached by the SHP EIR, Project impacts to paleontological resources within the on-site drainages would be less than significant. However, the majority of the remaining portions of the Project site are considered to have a “high” sensitivity for paleontological resources. Thus, and consistent with the conclusion reached by the SHP EIR, Project impacts to paleontological resources would be potentially significant within the portions of the Project site containing the following geologic formations (as shown on Figure 1 of the Project’s PRA, included as Technical Appendix F): 1) Very old alluvial fan deposits; 2) Silverado Formation; 3) Williams and Ladd Formations, undifferentiated; 4) Ladd Formation; and 5) Ladd Fm., Baker Canyon Conglomerate Member. (BFSA, 2023b, p. 7)

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However, the proposed Project would be subject to compliance with SHP EIR Mitigation Measures CR-2 through CR-4 requiring the preparation and implementation of a PRIMP. Consistent with the finding of the SHP EIR, implementation of SHP EIR Mitigation Measures CR-2 through CR-4 would reduce the Project’s potential impacts to paleontological resources to below a level of significance. Therefore, with implementation of SHP EIR Mitigation Measures CR-2 through CR-4, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. (BFSA, 2023b, p. 7)
d) Would the Project disturb any human remains, including those interred outside of formal cemeteries? Skyline Heights Project EIR Findings: Less-than-Significant Impact. The SHP EIR found that in the unlikely event human remans are discovered during grading or construction activities within the site, compliance with State law (Health and Safety Code Section 7050.5) would be required and would mitigate for potential impacts to human remains. Therefore, the SHP EIR concluded that impacts related to the discovery of buried human remains would be less than significant and no mitigation is necessary. (Corona, 2015, pp. 4.D-16 to 4.D-17) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Consistent with the findings of the SHP EIR, the Project site is not a designated cemetery, nor is it located adjacent to one. There is no known history of human remains being interred outside formal cemeteries on the site, nor is the site recognized as being situated on a burial ground or having previously yielded human remains. Nevertheless, the remote potential exists that human remains may be unearthed during grading and excavation activities associated with Project construction.

If human remains are unearthed during Project construction, the construction contractor would be required by law to comply with California Health and Safety Code, § 7050.5, “Disturbance of Human Remains.” According to § 7050.5(b) and (c), if human remains are discovered, the County Coroner must be contacted and if the Coroner recognizes the human remains to be those of a Native American or has reason to believe that they are those of a Native American, the Coroner is required to contact the Native American Heritage Commission (NAHC) by telephone within 24 hours. Pursuant to California Public Resources Code § 5097.98, whenever the NAHC receives notification of a discovery of Native American human remains from a county coroner, the NAHC is required to immediately notify those persons it believes to be most likely descended from the deceased Native American. The descendants may, with the permission of the owner of the land, or his or her authorized representative, inspect the site of the discovery of the Native American human remains and may recommend to the owner or the person responsible for the excavation work means for treatment or disposition, with appropriate dignity, of the human remains and any associated grave goods. The descendants shall complete their inspection and make recommendations or preferences for treatment within 48 hours of being granted access to the site. According to Public Resources Code § 5097.94(k), the NAHC is authorized to mediate disputes arising between landowners and known descendants relating to the treatment and disposition of Native American human burials, skeletal remains, and items associated with Native American burials. Consistent with the conclusion reached by the SHP EIR, mandatory compliance with the applicable provisions of California Health and Safety Code § 7050.5 and California Public Resources Code § 5097 et. seq. would ensure that Project impacts to human remains would be less than significant.

Therefore, and based on the preceding analysis, Project impacts to human remains would be less than significant with mandatory regulatory compliance, and as such the proposed Project would not result in any new impact not

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already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.
e) Would the Project conflict with an applicable plan, policy, or regulation adopted for purposes of avoiding or mitigating physical impacts associated with cultural resources? Skyline Heights Project EIR Findings: Less-than-Significant Impact. The SHP EIR found that implementation of the SHP would not conflict with an applicable plan, policy, or regulation adopted for the purpose of avoiding or mitigating physical impacts associated with cultural resources, and therefore concluded that impacts would be less than significant. (Corona, 2015, pp. 4.D-17 to 4.D-19)
EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The SHP EIR was certified in 2017.

However, subsequent to certification of the SHP EIR, the City of Corona City Council adopted an update to the City’s General Plan in 2020, with the most recent amendment to the General Plan occurring in April 2024.

Accordingly, Table 22, Project Consistency with General Plan Policies Related to Cultural Resources, provides an updated analysis of the proposed Project’s consistency with the 2020 General Plan policies related to cultural resources. As indicated in Table 22, the Project would be consistent with, or otherwise would not conflict with, all applicable goals and policies of the General Plan with respect to cultural resources. Accordingly, Project impacts due to a conflict with General Plan goals and policies related to cultural resources would be less than significant.

Therefore, implementation of the Project would not result in any new impacts not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified in the SHP EIR.

Table 22 Project Consistency with General Plan Policies Related to Cultural Resources Goal/Policy Project Consistency
Goal HR-1: A comprehensive historic resource
management program that identifies, designates, and
protects resources that are significant to the historic development, identity, and character of Corona
Not Applicable. Goal HR-1 provides direction to City staff and decision makers regarding implementation of a
comprehensive historic resource management program,
and is unrelated to the proposed Project.

Notwithstanding, the Project would result in less-thansignificant impacts to historic resources, as no such resources are known to occur on the site and none are
likely to be uncovered during site grading activities.

Policy HR-1.1: Continue to implement and expand upon,
as feasible, the following historic resources management strategies:
• A local Corona Historic Register that includes
significant “Landmark” properties, “Historic Districts,” and “Historical Markers” as prescribed in the Corona
Municipal Code.
• A Corona Heritage Inventory that includes surveyed
properties meeting all the criteria as prescribed in the Corona Municipal Code to be considered a local
historic resource.
• Procedures and criteria for determining the eligibility for listing properties on the Corona Historic Register
and the Corona Heritage Inventory.

Not Applicable. Policy HR-1.1 provides direction to City staff and decision makers regarding historic resources
management strategies, and is unrelated to the proposed Project. Notwithstanding, the Project would result in lessthan-significant impacts to historic resources, as no such resources are known to occur on the site and none are
likely to be uncovered during site grading activities.

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Goal/Policy Project Consistency
• Standards and regulations governing the identification, protection, restoration, maintenance, alteration,
relocation, or removal of historic resources.

Policy HR-1.2: Expand existing surveys of historic resources to include areas of potential historic importance not
previously surveyed, and develop an ongoing program for updating the surveys on a regular basis.

Consistent. The Project’s CRA included an updated site
investigation that confirmed the presence of two
previously-identified historic resources, both of which were determined to be ineligible for listing in the CRHR.

Policy HR-1.3: Continue to implement criteria and
guidelines for the inclusion of historic resources and
historic structures for the Historic Register and Heritage Inventory, including but not limited to: sites, parks,
landscape elements, streets, streetlights, signs,
monuments, murals, and public art.

Not Applicable. Policy HR-1.3 provides direction to City staff and decision makers regarding implementation of
criteria and guidelines for the inclusion of historic
resources in the Historic Register and Heritage Inventory.

Notwithstanding, the Project’s CRA included an updated
site investigation that confirmed the presence of two
previously-identified historic resources, both of which were determined to be ineligible for listing in the CRHR.

Policy HR-1.4: Continue to implement and expand upon
preservation incentive programs that encourage property owners to preserve, restore, and maintain historic
properties, and secure public and private funding sources to assist in said preservation.

Not Applicable. Policy HR-1.4 provides direction to City staff and decision makers regarding the implementation
and expansion of preservation incentive programs that
encourage property owners to preserve, restore, and
maintain historic properties, and is unrelated to the
proposed Project, which would result in less-thansignificant impacts to historical resources.

Policy HR-1.5: Support the preservation of historic
resources controlled by other governmental agencies,
including those related to federal, state, county, school district, and other agencies. This includes resources under the jurisdiction of the Army Corps of Engineers at Prado Basin.

Not Applicable: Policy HR-1.5 provides direction to City staff and decision makers regarding providing support for the preservation of historic resources controlled by other agencies, and is unrelated to the proposed Project.

Policy HR-1.6: Seek and support City-sponsored, nonprofit, and privately sponsored public events and festivals, as feasible, that recognize and promote the cultural and
historic heritage of Corona.

Not Applicable: Policy HR-1.6 provides direction to City staff and decision makers to support public events and
festivals promoting the cultural and historic heritage of the City of Corona, and is unrelated to the proposed Project.

Goal HR-2: Promote the retention, restoration, adaptive reuse, and maintenance of historic structures and
properties in a manner that will conserve the integrity of the resource in the best possible condition.

Not Applicable: Goal HR-2 provides direction to City staff and decision makers regarding the retention, restoration, adaptive reuse and maintenance of historic structures and properties. Based on the results of the Project’s CRA, the Project site does not include any historic resources eligible for listing on the CRHR; thus, Goal HR-2.1 is not applicable to the proposed Project.

Policy HR-2.1: Assist and encourage property owners and tenants to maintain the character and integrity of the
historic resource, and to restore and reuse historic
properties in a manner compatible with their original
architectural style.

Not Applicable: Policy HR-2.1 provides direction to City staff and decision makers to assist property owners and tenants to maintain the character and integrity of historic resources. Based on the results of the Project’s CRA, the Project site does not include any historic resources eligible for listing on the CRHR; thus, Policy HR-2.1 is not applicable to the proposed Project.

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Goal/Policy Project Consistency
Policy HR-2.2: Continue to implement design guidelines for restoring historic and architecturally significant structures, including but not limited to, the Secretary of the Interior’s Guidelines for Preserving, Rehabilitating, Restoring, and Reconstructing Historic Buildings.

Not applicable: Policy HR-2.2 provides direction to City staff and decision makers regarding the implementation of design guidelines for restoring historic and architecturally significant structures. Based on the results of the Project’s CRA, the Project site does not include any historic
resources eligible for listing on the CRHR; thus, Policy HR2.2 is not applicable to the proposed Project.

Policy HR-2.3: Develop an inventory of information and
resources regarding the proper rehabilitation techniques to assist owners and developers of historic buildings.

Not applicable: Policy HR-2.3 provides direction to City staff and decision makers to develop an inventory of
information and resources regarding the proper
rehabilitation techniques to assist owners and developers of historic buildings, and is unrelated to the proposed Project.

Policy HR-2.4: Administer the State Historic Building Code to facilitate the restoration and rehabilitation of historic structures in a manner that is more appropriated to older structures than the standard building codes.

Not Applicable: Policy HR-2.4 relates to historic buildings, while the results of the Project’s CRA indicate the Project site does not include any historic resources eligible for listing on the CRHR; thus, Policy HR-2.4 is not applicable to the proposed Project.

Policy HR-2.5: Require all modifications to historic
properties to be consistent with the Secretary of the
Interior’s “Standards for the Treatment of Historic
Properties with Guidelines for Preserving, Rehabilitating, Restoring, and Reconstructing Historic Buildings” or
“Standards for Rehabilitation and Guidelines for
Rehabilitating Historic Buildings.”
Not Applicable: Policy HR-2.5 relates to historic properties, while the results of the Project’s CRA indicate the Project site does not include any historic resources eligible for listing on the CRHR; thus, Policy HR-2.5 is not applicable to the proposed Project.

Goal HR-3: Recognize the importance of archeological and paleontological resources and ensure the identification and protection of those resources within the City of Corona.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which would reduce the Project’s potential impacts to
archaeological and paleontological resources to below a level of significance.

Policy HR-3.1: Require appropriate treatment/preservation of archaeological collections in a culturally appropriate manner, in accordance with state and federal standards, and in consultation with interested Native American tribes that have traditional cultural affiliation with the project area and/or the resources affected by the project.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.1.

Policy HR-3.2: Require that development proposals
incorporate specific measures to identify, protect, and preserve cultural resources in the planning, environmental review, and development process.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.2.

Policy HR-3.3: Archaeological resources found prior to or during construction shall be evaluated by a qualified
archaeologist and appropriate mitigation measures
applied, pursuant to § 21083.2 of CEQA, before the
resumption of development activities. Any measures
applied shall include the preparation of a report meeting professional standards, which shall be submitted to the Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.3.

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Goal/Policy Project Consistency
appropriate CHRIS information center.

Policy HR-3.4: Any project that involves earth-disturbing activities in an area determined to be archaeologically or culturally sensitive shall require evaluation of the site by a qualified archaeologist. The applicant shall implement the recommendations of the archaeologist, subject to the
approval of the City. Planning Department.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.4.

Policy HR-3.5: Any project that involves earth-disturbing activities in an area determined to be archaeologically or culturally sensitive shall require consultation by the
applicant with interested federally recognized American Indian Tribe(s) that have a traditional cultural affiliation with the project area and/or the resources affected by the project, for the purposes of determining resources impacts and appropriate mitigation to address such impacts.

Applicant shall also arrange for monitoring of earthdisturbing activities by interested federally recognized American Indian Tribe(s) that have a traditional cultural affiliation with the project area and/or the resources
affected by the project, if requested.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.5.

Policy HR-3.6: Any project that involves earth-disturbing activities in soil or rock units known or reasonably
suspected to be fossil-bearing shall require monitoring by a qualified paleontologist retained by the project applicant for the duration of excavation or trenching.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.6.

Policy HR-3.7: Paleontological resources found prior to or during construction shall be evaluated by a qualified
paleontologist, and appropriate mitigation measures
applied, pursuant to § 21083.2 of CEQA, before the
resumption of development activities. Any measures
applied shall include the preparation of a report meeting professional standards, which shall be submitted to the Riverside County Museum of Natural History.

Consistent: The Project would be subject to compliance
with the mitigation measures presented in the SHP EIR,
which implement the requirements of Policy HR-3.7.

Policy HR-3.8: In the event of the discovery of a burial, human bone, or suspected human bone, all excavation or
grading in the vicinity of the find shall halt immediately and the area shall be protected and the project applicant immediately shall notify the Riverside County Coroner and comply with provisions of the Health and Safety Code §
7050.5, including PRC § 5097.98, if applicable. If the find is determined to be Native American human remains, the
applicant shall consult with the Most Likely Descendent to determine appropriate treatment for such remains.

Consistent: The Project would be subject to compliance
with the applicable provisions of California Health and Safety Code § 7050.5 and California Public Resources Code § 5097 et. seq. in the event of discovery of human remains during Project construction activities.

Goal HR-4: Recognize, identify, and protect natural
resources for their historic and cultural value, and include these features in the historic resource management
program.

Not applicable: Goal HR-4 provides direction to City staff and decision makers to recognize, identify, and protect natural resources for their historic and cultural value, and

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Goal/Policy Project Consistency
include these features in the historic resource management program, and is unrelated to the proposed Project.

Policy HR-4.1: Develop an inventory and map
concentrations of Heritage Street Trees, which are
representative of the City’s character and history, for consideration and official inclusion on the Corona Historic Register or the Heritage Inventory.

Not applicable: Policy HR-4.1 provides direction to City staff and decision makers to develop an inventory and map concentrations of Heritage Street Trees, and is unrelated to the proposed Project.

Policy HR-4.2: Designate “Landmark Trees” in accordance with existing City policy and ordinance to preserve and protect individual specimen trees, which display particular historic value to the community.

Not applicable: Policy HR-4.2 provides direction to City staff and decision makers to designate “Landmark Trees” in accordance with existing City policy and ordinance, and is unrelated to the proposed Project.

Policy HR-4.3: List applicable parks within Grand Boulevard, as resources on the Corona Historic Register, to preserve their historic identity and become eligible for funding for future restoration and maintenance.

Not applicable: Policy HR-4.2 provides direction to City staff and decision makers to list applicable parks within Grand Boulevard as resources on the Corona Historic
Register, and is unrelated to the proposed Project.

Goal HR-5: Foster increased community awareness and
appreciation for Corona’s unique heritage and the many
cultural and historical resources found in the City.

Not applicable: Goal HR-5 provides direction to City staff and decision makers to foster increased community
awareness and appreciation for Corona’s unique heritage and the many cultural and historical resources found in the City, and is unrelated to the proposed Project.

Policy HR-5.1: Encourage, participate in, and promote
activities and events designed to educate the community about Corona’s unique heritage and the recognition of its many cultural and historic resources.

Not applicable: Policy HR-5.1 provides direction to City staff and decision makers to encourage, participate in, and promote activities and events designed to educate the
community about Corona’s unique heritage and the
recognition of its many cultural and historic resources, and is unrelated to the proposed Project.

Policy HR-5.2: Promote the archival collection and
documentation of Corona’s history at the Heritage Room of the Corona Public Library, and establish this facility as the official local repository for historic and cultural resource records.

Not applicable: Policy HR-5.2 provides direction to City staff and decision makers to promote the archival
collection and documentation of Corona’s history at the Heritage Room of the Corona Public Library and establish this facility as the official local repository for historic and cultural resource records, and is unrelated to the proposed Project.

Policy HR-5.3: Develop educational and interpretive
brochures for distribution to the public and property
owners about the City’s historic resources, preservation programs, financial incentives for designated properties, and restoration requirements and guidelines.

Not applicable: Policy HR-5.3 provides direction to City staff and decision makers to develop educational and
interpretive brochures, and is unrelated to the proposed Project.

Policy HR-5.4: Foster neighborhood conservation and
beautification programs and consider preservation awards or recognition certificates for historic properties displaying exceptional care, maintenance, or restoration.

Not applicable: Policy HR-5.4 provides direction to City staff and decision makers to foster neighborhood
conservation and beautification programs and consider
preservation awards or recognition certificates for historic properties, and is unrelated to the proposed Project.

Policy HR-5.5: Inform property owners of the benefits of being a listed historic property and provide information on conservation methods and professional resources.

Not applicable: Policy HR-5.5 provides direction to City staff and decision makers to inform property owners of the benefits of being a listed historic property and provide

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Goal/Policy Project Consistency
information on conservation methods and professional
resources, and is unrelated to the proposed Project.

Goal HR-6: Build and strengthen preservation partnerships between the City and property owners, businesses,
community organizations, educational institutions, and
State and federal agencies.

Not applicable: Goal HR-6 provides direction to City staff and decision makers to build and strengthen preservation partnerships between the City and property owners,
businesses, community organizations, educational
institutions, and State and federal agencies, and is
unrelated to the proposed Project.

Policy HR-6.1: Coordinate with the Chamber of Commerce, Corona Historic Preservation Society, State Office of
Historic Preservation, and other organizations or agencies regarding potential programs that promote tourism,
filming, and economic development in association with
historic resources.

Not applicable: Policy HR-6.1 provides direction to City staff and decision makers to coordinate with the Chamber of Commerce, Corona Historic Preservation Society, State Office of Historic Preservation, and other organizations or agencies, and is unrelated to the proposed Project.

Policy HR-6.2: Encourage the involvement of the CoronaNorco Unified School District in preservation activities, local history programs, and the potential listing of
identified historic school sites on the Corona Historic Register.

Not applicable: Policy HR-6.2 provides direction to City staff and decision makers to encourage the involvement of the Corona-Norco Unified School District in preservation activities, local history programs, and the potential listing of identified historic school sites, and is unrelated to the proposed Project.

Policy HR-6.3: Work cooperatively with the Corona
Heritage Foundation in the establishment and
improvement of Heritage Park as a historic citrus ranch complex in South Corona.

Not applicable: Policy HR-6.3 provides direction to City staff and decision makers to work cooperatively with the Corona Heritage Foundation in the establishment and
improvement of Heritage Park as a historic citrus ranch complex in South Corona, and is unrelated to the proposed Project, which is not located within South Corona.

Policy HR-6.4: Consider application to the State of
California Historic Preservation Office for acceptance as a Certified Local Government, and for having a Certified
Local Ordinance for historic resource management.

Not applicable: Policy HR-6.4 provides direction to City staff and decision makers to consider application to the State of California Historic Preservation Office for
acceptance as a Certified Local Government, and is
unrelated to the proposed Project.

Policy HR-6.5: Continue to consider and assist in the
nomination of Corona’s historic resources to the National Register of Historic Places, the California Historic
Landmarks program, and the California Points of Historical Interest program.

Not applicable: Policy HR-6.5 provides direction to City staff and decision makers to consider and assist in the nomination of Corona’s historic resources to the National Register of Historic Places, the California Historic
Landmarks program, and the California Points of Historical Interest program, and is unrelated to the proposed Project.

Policy HR-6.6: Work cooperatively with the Corona Historic Preservation Society, and other nonprofit and community organizations, in the placement of appropriate Historical Markers, monuments, or plaques to memorialize historic
sites in Corona.

Not applicable: Policy HR-6.6 provides direction to City staff and decision makers to work cooperatively with the Corona Historic Preservation Society, and other nonprofit and community organizations, in the placement of
appropriate Historical Markers, monuments, or plaques to memorialize historic sites in Corona, and is unrelated to the proposed Project.

Policy HR-6.7: Work cooperatively with the Corona Historic Preservation Society and other nonprofit organizations and Not applicable: Policy HR-6.7 provides direction to City staff and decision makers to work cooperatively with the

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Goal/Policy Project Consistency
individuals applying for available local, State, and federal funding for the rehabilitation and restoration of historic properties and resources.

Corona Historic Preservation Society and other nonprofit organizations and individuals applying for available local, State, and federal funding for the rehabilitation and
restoration of historic properties and resources, and is unrelated to the proposed Project.

Mitigation Measures
The following mitigation measures from the SHP EIR shall apply in order to reduce the Project’s potential impacts to cultural resources to below a level of significance. Revisions/additions to the SHP EIR Mitigation Measures are shown below in strikeout/underline format, and have been made to reflect the results of the Project’s PRA. The revisions to the SHP EIR mitigation measures reflect more stringent requirements as compared to the mitigation measures included in the SHP EIR.

CR-1 Tribal Monitoring. Prior to the issuance of a grading permit the applicant shall contact the consulting Native American Tribe(s) that have requested monitoring through consultation with the City during the SB 18 process ("Monitoring Tribes”). The applicant shall coordinate with the Tribe(s) to develop individual Tribal Monitoring Agreement(s). A copy of the signed agreement(s) shall be provided to the City of Corona Planning Department prior to the issuance of a grading permit. The Agreement shall address the treatment of any known tribal cultural resources (TCRs) including the project's approved mitigation measures and conditions of approval; the designation, responsibilities, and participation of professional Tribal Monitors during grading, excavation and ground disturbing activities; project grading and development scheduling: terms of compensation for the monitors; and treatment and final disposition of any cultural resources, sacred sites, and human remains/burial goods discovered on the site per the Tribe(s) customs and traditions and the City’s mitigation measures/conditions of approval. The Tribal Monitor will have the authority to stop and redirect grading in the immediate area of a find in order to evaluate the find and determine the appropriate next steps, in consultation with the Project archaeologist.

If changes are made to the project footprint to include earth-moving activities in areas not previously studied, additional archaeological investigations shall be required.

In the event that archaeological materials are discovered during construction, all earth-moving activity within and around the immediate discovery area shall be diverted until a qualified archaeologist can assess the nature and significance of the find, and, if necessary, develop appropriate treatment measures. Treatment measures typically include development of avoidance strategies, capping with fill material, or mitigation of impacts through data recovery programs such as excavation or detailed documentation. If during cultural resources monitoring the qualified archaeologist determines that the sediments being excavated are previously disturbed or unlikely to contain significant cultural materials, the qualified archaeologist can specify that monitoring be reduced or eliminated.

Native American monitors from affected Tribes shall observe all project-related grading activities, and the treatment of any recovered artifacts shall be carried out in accordance with the provisions of a Treatment Agreement between affected Tribes. The Treatment Agreement shall be executed by the consulting Tribes prior to the issuance of grading permits for each construction phase. All

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cultural materials that are collected during the grading monitoring program and from any previous archaeological studies or excavations on the project site shall be curated according to the current professional repository standards. The collections and associated records shall be transferred, including title, to an appropriate curation facility which meets the standards set forth in 36 CFR Part 79 for federal repositories. All sacred sites, should they be encountered within the project area, shall be avoided and preserved as the preferred mitigation.

If changes are made to the project footprint to include earth-moving activities in areas not previously studied, additional archaeological investigations shall be required.

CR-2: Archaeological Monitoring. At least 30-days prior to application for a grading permit and before any grading, excavation and/or ground disturbing activities on the site take place, the Project Applicant shall retain a Secretary of Interior Standards qualified and RPA-certified archaeological monitor to monitor all ground-disturbing activities in an effort to identify any unknown archaeological resources/TCRs and assist with avoidance, preservation and/or mitigation per the City's Mitigation Measures on known resources.

The Project Archaeologist in consultation with the Monitoring Tribe(s), the Developer and the City, shall develop a Cultural Resources Monitoring Plan (CRMP) to address the details, timing and responsibility of all archaeological and cultural activities that will occur on the project site. Details in the Plan shall include:
a. Project grading and development scheduling;
b. The Project archeologist and the Monitoring Tribe(s) shall attend the pre-grading meeting with the construction manager and any contractors and will conduct a mandatory Cultural Resources Worker Sensitivity Training to those in attendance. The Training will include a brief review of the cultural sensitivity of the Project and the surrounding area: what resources could potentially be identified during earthmoving activities; the requirements of the monitoring program: the protocols that apply in the event inadvertent discoveries of cultural resources are identified, including who to contact and appropriate avoidance measures until the find(s) can be properly evaluated; and any other appropriate protocols. All new construction personnel that begin work on the Project following the initial Training must take the Cultural Sensitivity Training prior to beginning work and the Project archaeologist and Monitoring Tribe(s) shall make themselves available to provide the training on an as-needed basis. c. The coordination of a monitoring schedule as agreed upon by the Monitoring Tribe(s), the Project archaeologist and the applicant;
d. The protocols and stipulations that the Developer. City, Monitoring Tribe(s) and Project archaeologist will follow in the event of inadvertent cultural resources discoveries, including any newly discovered cultural resource deposits that shall be subject to a cultural resources evaluation.

Prior to issuance of any grading permit, the Applicant shall retain a qualified vertebrate [sic] to develop a paleontological resource impact mitigation program (PRIMP) for excavations into the Upper Cretaceous Ladd Canyon Formation [sic], the Upper Cretaceous Williams Formation, ; and the Paleocene Silverado Formation. A qualified vertebrate paleontologist is defined as a paleontologist meeting the criteria established by the Society of Vertebrate Paleontology. The

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qualified vertebrate paleontologist shall conduct a preconstruction field assessment to locate fossils at surface exposures. The qualified vertebrate paleontologist shall supervise a paleontological monitor who shall be present at such times as required by the paleontologist during construction excavations into the fossiliferous formations referenced above. Monitoring shall consist of visually inspecting fresh exposures of rock for larger fossil remains and, where appropriate, collecting wet or dry screened sediment samples of promising horizons for smaller fossil remains. The frequency of monitoring shall be determined by the paleontologist and shall be based on the rate of excavation and grading activities, the materials being excavated, and the depth of excavation, and if found, the abundance and type of fossils encountered. If resources are located, monitoring hours shall be increased if needed.

CR-3: Treatment and Disposition of Tribal Cultural Resources. In the event that Tribal Cultural Resources (TCRs) are inadvertently discovered during the course of grading for this Project and avoidance of the TCRs is not feasible, the following procedures will be carried out for treatment and disposition of the discoveries:

1. Temporary Curation and Storage: During the course of construction. All discovered resources shall be temporarily curated in a secure location onsite or at the offices of the project archaeologist. The removal of any artifacts from the project site will need to be thoroughly inventoried with tribal monitor oversight of the process: and

2. Treatment and Final Disposition: The landowner(s) shall relinquish ownership of all cultural resources, including all archaeological artifacts and non-human remains as part of the required mitigation for impacts to tribal cultural resources. Human remains, sacred/ceremonial items and burial good will be addressed per State Law. Mitigation Measure CR-1 and the Agreement required in Mitigation Measure CR-1. The applicant shall relinquish the artifacts as indicated below and provide the City of Corona Planning Division with evidence of same:
a. Professional curation, including a curation agreement with a qualified repository in Riverside County that meets federal standards per 36 CFR Part 79, and which shall be made available to all qualified researchers upon application. The collections and associated records shall be transferred, including title, to an appropriate curation facility within Riverside County, to be accompanied by payment of the fees necessary for permanent curation;
b. At the completion of grading, excavation and ground disturbing activities on the site, a Phase IV Monitoring Report shall be submitted to the City Planning Division documenting monitoring activities conducted by the project Archaeologist and Native Tribal Monitors within 60 days of completion of grading. This report shall document the impacts to the known resources on the property; describe how each mitigation measure was fulfilled; document the type of cultural resources recovered and the disposition of such resources; provide evidence of the required cultural sensitivity training for the construction staff held during the required pregrade meeting; and, in a confidential appendix, include the daily/weekly monitoring notes from the archaeologist. All reports produced will be submitted to the City of Corona, Eastern Information Center and Monitoring Tribe(s).

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If a potential fossil is found, the qualified vertebrate paleontologist or paleontological monitor shall be allowed to temporarily divert or redirect grading and excavation activities in the area of the exposed fossil, as determined appropriate by the monitor, to assess the significance of the find and, if necessary, develop appropriate treatment measures. Treatment measures may include avoidance or preservation in place, if feasible. If preservation or avoidance of the resource is not feasible, then the resource shall be removed from its location. Removal activities may consist of the relatively rapid removal of small isolated fossils from an active cut, to hand-quarrying of larger fossils from a bone bed over several days. These activities may include the assistance of the grading and excavation contractor’s equipment to facilitate removal. Any fossils encountered and recovered shall be prepared to the point of identification and catalogued before they are donated to their final repository. Any fossils collected shall be donated to a public, non-profit institution with a research interest in the materials, such as the Natural History Museum of Los Angeles County, San Bernardino County Museum, the John D. Cooper Archaeological and Paleontological Curation Center at the California Sate University, Fullerton, or Western Science Center in Hemet, California. Accompanying notes, maps, and photographs shall also be filed at the repository.

CR-4: Sacred Sites. All sacred sites, should they be encountered within the project area, shall be avoided and preserved as the preferred mitigation, if feasible. Prior to the release of the grading bond, the paleontologist shall prepare a report summarizing the results of the monitoring and salvaging efforts, the methodology used in these efforts, as well as a description of the fossils collected and their significance. The report shall be submitted by the Applicant to the Community Development Director or his/her designee for approval. In addition, the report shall be submitted to at least one of the repositories mentioned in Mitigation Measure CR-3 and other appropriate or concerned agencies to signify the satisfactory completion of the project and required mitigation measures.

CR-5 Discovery of Human Remains. In the event that human remains (or remains that may be human) are discovered at the project site during grading or earthmoving. the construction contractors, project archaeologist, and/or designated Native American Monitor shall immediately stop all activities within 100 feet of the find. The project applicant shall then inform the Riverside County Coroner and the City of Corona Planning Division immediately, and the coroner shall be permitted to examine the remains as required by California Health and Safety Code Section 7050.5(b).

Section 7050.5 requires that excavation be stopped in the vicinity of discovered human remains until the coroner has made the necessary findings as to origin If human remains are determined to be Native American,, the applicant shall comply with the state law relating to the disposition of Native American burials that fall within the jurisdiction of the NARC (PRC Section 5097). The coroner shall contact the NAHC within 24 hours and the NAHC will make the determination of most likely descendant(s). The MLD shall complete his or her inspection and make recommendations or preferences for treatment within 48 hours of being granted access to the site. Treatment and disposition of the remains shall be determined in consultation with the most likely descendant(s) to determine the most appropriate disposition of human remains and any associated grave artifacts. In the event that the applicant and the MLD are in disagreement regarding the disposition of the remains. State law will apply and the mediation process will occur with the NAHC. if requested (see PRC Section 5097.98(e) and 5097.94(k)).

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The specific locations of Native American burials and reburials are confidential and may not be disclosed to the general public. The locations will be documented by the consulting archaeologist in conjunction with the various stakeholders and a report of findings will be filed with the Eastern Information Center (EIC). A Sacred Lands File form will be submitted to the NAHC by the project archaeologist and the Monitoring Tribe(s).

According to the California Health and Safety Code, six or more human burials at one location constitutes a cemetery (Section 8100), and disturbance of Native American cemeteries is a felony (Section 7052).

CR-62 Prior to issuance of any grading permit, the Applicant shall retain a qualified vertebrate paleontologist [sic] to develop a paleontological resource impact mitigation program (PRIMP) for excavations into the Upper Cretaceous Ladd Canyon Formation [sic], the Upper Cretaceous Williams and Ladd Formations (undifferentiated), the Early Pleistocene Very Old Alluvial Fan Deposits; the Upper Cretaceous Ladd Forma�on/Baker Canyon Conglomerate member; and Paleocene Silverado Formation. A qualified vertebrate paleontologist is defined as a paleontologist meeting the criteria established by the Society for Vertebrate Paleontology. The qualified vertebrate paleontologist shall conduct a pre-construction field assessment to locate fossils at surface exposures. The qualified vertebrate paleontologist shall supervise a paleontological monitor who shall be present at such times as required by the paleontologist during construction excavations into the fossiliferous formations mentioned above. Monitoring shall consist of visually inspecting fresh exposures of rock for larger fossil remains and, where appropriate, collecting wet or dry screened sediment samples of promising horizons for smaller fossil remains. The frequency of monitoring shall be determined by the paleontologist and shall be based on the rate of excavation and grading activities, the materials being excavated, and the depth of excavation, and if found, the abundance and type of fossils encountered. If resources are located, monitoring hours shall be increased as needed.

CR-73 If a potential fossil is found, the qualified vertebrate paleontologist or paleontological monitor shall be allowed to temporarily divert or redirect grading and excavation activities in the area of the exposed fossil, as determined appropriate by the monitor, to assess the significance of the find and, if necessary, develop appropriate treatment measures. Treatment measures may include avoidance or preservation in place, if feasible. If preservation or avoidance of the resource is not feasible, then the resource shall be removed from its location. Removal activities may consist of the relatively rapid removal of small isolated fossils from an active cut, to hand-quarrying of larger fossils over several hours, to excavations of large fossils or large numbers of smaller fossils from a bone bed over several days. These activities may include the assistance of the grading and excavation contractor’s equipment to facilitate removal. Any fossils encountered and recovered shall be prepared to the point of identification and catalogued before they are donated to their final repository. Any fossils collected shall be donated to a public, non-profit institution with a research interest in the materials, such as the Natural History Museum of Los Angeles County, San Bernardino County Museum, the John D. Cooper Archaeological and Paleontological Curation Center at the California State University, Fullerton, or Western Science Center in Hemet, California.

Accompanying notes, maps, and photographs shall also be filed at the repository.

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CR-84 Prior to the release of the grading bond, the paleontologist shall prepare a report summarizing the results of the monitoring and salvaging efforts, the methodology used in these efforts, as well as a description of the fossils collected and their significance. The report shall be submitted by the Applicant to the Planning Director or his/her designee for approval. In addition, the report shall be submitted to at least one of the repositories mentioned in Mitigation Measure CR-7 and other appropriate or concerned agencies to signify the satisfactory completion of the project and required mitigation measures.

2.6 Energy
New
Significant
Impact
More
Severe
Impacts
New Ability to
Substantially Reduce
Significant Impact
No Substantial
Change from
Previous Analysis
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? ☐ ☐ ☐ ☒

ENVIRONMENTAL ANALYSIS
a) Would the Project result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation? Skyline Heights Project EIR Findings: Although SHP EIR did not address this subject because it was not a required CEQA topic at the time the SHP EIR was adopted, the SHP EIR contained enough information about projected energy consumption associated with the SHP that with the exercise of reasonable diligence, information about the SHP’s potential effect due to energy conservation was readily available to the public. Specifically, Technical Appendix C to the SHP EIR included an Air Quality and Greenhouse Gas Analysis and SHP EIR Subsection 4.F, Greenhouse Gas Emissions, provided a discussion of the SHP project’s anticipated greenhouse gas (GHG) emissions, including the GHG emissions related to energy consumption. The SHP EIR and Technical Appendix C documented the energy conservation requirements applicable to buildout of the SHP, including a description of the requirements of California’s Energy Efficiency Standards for Residential and Nonresidential Buildings and the California Green Building Standards. Additionally, Appendix A to SHP EIR Technical Appendix C included the CalEEMod outputs, which indicated that long-term operation of the SHP would result in a future unmitigated demand for 9,826,170 kBTU/yr of natural gas and 2,234,780 kWh per year of electricity. Subsection 4.N of the SHP EIR also included a detailed discussion of applicable State regulations related to energy conservation. The SHP EIR did not identify any impacts due to the wasteful, inefficient, or unnecessary consumption of energy resources and did not identify any impacts due to a conflict with or obstruction of a State or local plan for renewable energy or energy efficiency.

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EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Although the issue of Energy was not explicitly evaluated in the SHP EIR as detailed impact analysis was not required at that time, the SHP EIR did acknowledge that future buildout of the SHP area would increase consumption of electricity and natural gas resources. However, the currently proposed Project includes 16 fewer dwelling units as compared to the project evaluated in the SHP EIR; thus, the proposed Project would result in an overall reduction in energy demand as compared to the project evaluated by the SHP EIR. Regulations and other energy standards have also only become more stringent since the certification of the SHIP EIR, and as a result, the proposed Project is also likely to require less energy on a per unit basis than the Approved Project.

Specifically, the proposed Project would be required to meet at a minimum the 2022 version of the California Title 24 energy efficiency requirements, which became effective on January 1, 2023, and impose more stringent energy efficiency requirements in comparison to the 2013 or 2016 versions of the Title 24 regulations that were in effect at the time the SHP EIR was prepared and certified, respectively. The 2022 Title 24 standards require solar photovoltaic systems for new homes, encourage demand responsive technologies for residential buildings, and update indoor and outdoor lighting standards for nonresidential buildings. The California Energy Commission (CEC) anticipates that the 2022 energy code will provide $1.5 billion in consumer benefits and reduce GHG emissions by 10 million metric tons. Additionally, nonresidential buildings will use approximately 30% less energy due to lighting upgrades compared to the prior code. (CEC, 2022) The Project’s compliance with the current version of the Title 24 standards would ensure that the Project energy demands would not be inefficient, wasteful, or otherwise unnecessary. The Project would not cause or result in the need for additional energy producing or transmission facilities. The Project would not engage in wasteful or inefficient uses of energy and aims to achieve energy conservations goals within the State of California.

In addition, the currently-proposed Project would be subject to compliance with all applicable State and local regulations related to renewable energy and energy efficiency. Additionally, and as noted above, the Project would be subject to compliance with the 2022 version of Title 24, which imposes more stringent requirements related to energy efficiency as compared to what was required by the 2013 or 2016 version of Title 24. Because the Project would be required to comply with all applicable regulations related to energy efficiency, the Project would not result in potentially significant environmental impacts due to a conflict with or obstruct a State or local plan for renewable energy or energy efficiency, and impacts would be less than significant.

The Project also would result in a reduction in overall traffic associated with the AVSP site. Specifically, and as shown in Table 4-2, Trip Generation Comparison, of the Project’s Traffic Analysis (“TA”; Technical Appendix J), the Project, which includes 16 fewer units than the project evaluated by the SHP EIR, would result in a net reduction of 176 average daily trips (ADT). Thus, it can be concluded that the proposed Project would result in a substantial reduction in the amount of transportation-related fuel that would be consumed by the Project as compared to the project evaluated by the SHP EIR. Additionally, due to increasing regulatory requirements related to fuel efficiency, vehicles associated with the currently-proposed Project would have a higher level of fuel efficiency and would consume less fossil fuels as compared to the project evaluated by the SHP EIR. Thus, the Project’s overall transportation-related energy demands would be less than what was assumed by the SHP EIR.

As supported by the preceding analyses, Project operations would not result in the inefficient, wasteful, or unnecessary consumption of energy, and impacts would be less than significant. Therefore, the proposed Project

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would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. b) Would the Project conflict with or obstruct a state or local plan for renewable energy or energy efficiency?
Under existing conditions, there are no adopted State or local plans for renewable energy or energy efficiency in the Project area. Thus, the Project would have no potential to conflict with such plans, and no impact would occur.

Additionally, and as discussed below, the Project would be consistent with or otherwise would not conflict with policies and requirements related to energy conservation. • Project Consistency with Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991: The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) promoted the development of intermodal transportation systems to maximize mobility as well as address national and local interests in air quality and energy. ISTEA contained factors that Metropolitan Planning Organizations (MPOs) were to address in developing transportation plans and programs, including some energy-related factors. To meet the new ISTEA requirements, MPOs adopted explicit policies defining the social, economic, energy, and environmental values guiding transportation decisions.

Transportation and access to the Project site is provided primarily by the local and regional roadway systems. The Project would not interfere with, nor otherwise obstruct intermodal transportation plans or projects that may be realized pursuant to the ISTEA because SCAG is not planning for intermodal facilities on or through the Project site.
• Project Consistency with the Transportation Equity Act for the 21st Century (TEA-21): The Transportation Equity Act for the 21st Century (TEA-21) was signed into law in 1998 and builds upon the initiatives established in the ISTEA legislation, discussed above. TEA-21 authorizes highway, highway safety, transit, and other efficient surface transportation programs. TEA-21 continues the program structure established for highways and transit under ISTEA, such as flexibility in the use of funds, emphasis on measures to improve the environment, and focus on a strong planning process as the foundation of good transportation decisions. TEA-21 also provides for investment in research and its application to maximize the performance of the transportation system through, for example, deployment of Intelligent Transportation Systems, to help improve operations and management of transportation systems and vehicle safety.

The Project site is located along major transportation corridors with proximate access to the Interstate freeway system. The site selected for the Project facilitates access, acts to reduce Vehicle Miles Traveled (VMT), takes advantage of existing infrastructure systems, and promotes land use compatibilities through collocation of similar uses. This is because the Project site is located within an area already served with roadway and utilities infrastructure and the Project site is located in an area surrounded by existing and planned residential development. As such, the Project supports the strong planning processes emphasized under TEA-21 by taking advantage of the regional and proximate transportation infrastructure. The Project is therefore consistent with, and would not otherwise interfere with, nor obstruct implementation of TEA-21.

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• Project Consistency with the California Integrated Energy Policy Report (Senate Bill 1389): Senate Bill 1389 (Bowen, Chapter 568, Statutes of 2002) requires the California Energy Commission to prepare a biennial integrated energy policy report that assesses major energy trends and issues facing the State’s electricity, natural gas, and transportation fuel sectors and provides policy recommendations to conserve resources; protect the environment; ensure reliable, secure, and diverse energy supplies; enhance the state’s economy; and protect public health and safety (Public Resources Code § 25301a). The Energy Commission prepares these assessments and associated policy recommendations every two years, with updates in alternate years, as part of the Integrated Energy Policy Report. The 2019 Integrated Energy Policy Report (2019 IEPR) was published in February 2020, and continues to work towards improving electricity, natural gas, and transportation fuel energy use in California.

Electricity would be provided to the Project by Southern California Edison (SCE). SCE’s Clean Power and Electrification Pathway (CPEP) white paper is an integrated approach to reduce GHG emissions and air pollution by taking action in three California economic sectors: electricity, transportation, and buildings.

It builds on existing state programs and policies, and uses a combination of measures to produce the most cost-effective and feasible path forward among the options studied. By 2030, it calls for: 1) an electric grid supplied by 80 percent carbon-free energy; 2) more than 7 million electric vehicles on California roads; and 3) using electricity to power nearly one-third of space and water heaters, in increasingly energyefficient buildings. These electrified technologies will use zero-emission resources like solar and wind to provide most of their power, and can in turn support the electric grid by balancing electricity demand with supply. Because all power supplied to the Project by SCE would be subject to the energy conservation and renewable energy requirements of the CPEP, the Project is inherently consistent with, would not otherwise interfere with, and would not obstruct implementation of, the goals presented in the 2019 IEPR. • Project Consistency with State Energy Plan: The CEC is responsible for preparing the State Energy Plan, which identifies emerging trends related to energy supply, demand, conservation, public health and safety, and the maintenance of a healthy economy. The Plan calls for the State to assist in the transformation of the transportation system to improve air quality, reduce congestion, and increase the efficient use of fuel supplies with the least environmental and energy costs. To further this policy, the plan identifies a number of strategies, including assistance to public agencies and fleet operators and encouragement of urban designs that reduce vehicle miles traveled and accommodate pedestrian and bicycle access.

The Project site is located along major transportation corridors with proximate access to the Interstate freeway system. The site selected for the Project facilitates access and takes advantage of existing infrastructure systems. The Project therefore supports urban design and planning processes identified under the State of California Energy Plan, is consistent with, and would not otherwise interfere with, nor obstruct implementation of the State of California Energy Plan. • Project Consistency with California Code Title 24, Part 6 (California Energy Code): California Code of Regulations Title 24 Part 6: California’s Energy Efficiency Standards for Residential and Nonresidential Buildings, was first adopted in 1978 in response to a legislative mandate to reduce California’s energy consumption. The standards are updated periodically to allow consideration and possible incorporation

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of new energy efficient technologies and methods. Energy efficient buildings require less electricity; therefore, increased energy efficiency reduces fossil fuel consumption and decreases GHG emissions.

The 2022 Title 24 standards require solar photovoltaic systems for new homes, establish requirements for newly constructed healthcare facilities, encourage demand responsive technologies for residential buildings, and update indoor and outdoor lighting for nonresidential buildings. The CEC previously indicated that single-family homes built with the 2019 standards will use approximately 7 percent less energy compared to the residential homes built under the 2016 standards, and the 2022 Title 24 standards are more stringent than the 2019 standards. Additionally, after implementation of solar photovoltaic systems, the CEC previously indicated homes built under the 2019 standards will about 53 percent less energy than homes built under the 2016 standards. Nonresidential buildings will use approximately 30 percent less energy due to lighting upgrades.

The Project would be subject to the updated 2022 Title 24 standards (or the incumbent version of Title 24 in effect at the time of building permit application). Compliance with the applicable Title 24 requirements is enforced through Section 14-65 of the City’s Municipal Code. Thus, Project consistency with Title 24 requirements would occur as part of the City’s future review of building permit applications. As such, the Project is consistent with, would not interfere with, and would not obstruct implementation of Title 24. • Project Consistency with Pavley Fuel Efficiency Standards (AB 1493): AB 1493 is not directly applicable to the Project, since it is a Statewide measure establishing vehicle emissions standards. No feature of the Project would interfere with implementation of the requirements under AB 1493. Additionally, all vehicles accessing the Project site would obtain fuel from local and regional distributors, which would be compliant with AB 1493.
• Project Consistency with California Renewable Portfolio Standards (SB 1078): The requirements of the State’s Renewable Portfolio Standard (RPS) are not applicable to the Project as it is a Statewide measure that establishes a renewable energy mix. However, no feature of the Project would interfere with implementation of the requirements under RPS.
• Project Consistency with Senate Bill 350 (SB 350): The proposed Project would use energy from SCE, which has committed to diversify their portfolio of energy sources by increasing energy from wind and solar sources. No feature of the Project would interfere with implementation of SB 350. The Project would be designed and constructed to implement the energy efficiency measures for new residential developments and would include several measures designed to reduce energy consumption. Additionally, under Title 24, the Project is required to install solar PV systems on each dwelling unit, which would feed back into the overall SCE power mix and, therefore the Project would partially support the goas of RPS and SB 350.

Conclusion
Based on the preceding analysis, the Project would not conflict with any adopted State or local plans for renewable energy or energy efficiency. Impacts due to the Project’s energy demands would be less than significant, and impacts would be reduced in comparison to the Approved Project. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

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2.7 Geology and Soils
New
Significant
Impact
More
Severe
Impacts
New Ability to
Substantially
Reduce
Significant Impact
No Substantial
Change from
Previous
Analysis
Would the Project:
a. Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:
• 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 420)
• Strong seismic ground shaking?
• Seismic-related ground failure, including
liquefaction?
• 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 1803.5.3 of the California Building Code (2022), creating
substantial risks to life or property?
☐ ☐ ☐ ☒
e. Have soils incapable of adequately supporting the
use of septic tanks or alternative waste water
disposal systems where sewers are not available for
the disposal of waste water?
☐ ☐ ☐ ☒
f. Conflict with an applicable plan, policy, or regulation adopted for purposes of avoiding or mitigating
physical impacts associated with geology and soils?
☐ ☐ ☐ ☒

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ENVIRONMENTAL ANALYSIS
In order to evaluate the proposed Project’s potential to result in significant impacts due to the site’s geologic and soil conditions, the analysis herein relies on two technical reports prepared by LGC Geotechnical, Inc. (herein, “LGC”). The first report provides a general geotechnical analysis of the site based on the approved version of TTM 36544, is titled, “Geotechnical Rough Grading Plan Review for the Proposed Skyline Heights Residential Development, Tract No. 36544, City of Corona, California” (herein, “Geotechnical Report”) is dated January 30, 2019, and is included as Technical Appendix G1 (LGC, 2019a). The second report addresses the site’s potential to contain or be affected by faults, is titled, “Updated Fault Evaluation for the Proposed "Skyline Heights" Residential Development, Tract No. 36544, City of Corona, California” (herein, “Fault Evaluation”), is dated January 22, 2019, and is included as Technical Appendix G2 (LGC, 2019b).
a) Would the Project expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:
• 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 420) • Strong seismic ground shaking?
• Seismic-related ground failure, including liquefaction? • Landslides?
Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that implementation of the SHP could expose people or structures to strong seismic ground shaking, seismicrelated ground failure, landslides, and other ground failure hazards. However, the SHP EIR found that adherence to the design and remedial recommendations of the Geotechnical Report, as required by SHP EIR Mitigation Measures GEO-1 through GEO-23, as well as compliance with applicable regulatory requirements, would reduce such impacts to a less-than-significant level. (Corona, 2015, pp. 4.E-18 to 4.E-21) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Provided below is an analysis of the Project’s potential to expose people or structures to substantial adverse effects associated with earthquake faults, strong seismic ground shaking, seismic-related ground failure (including liquefaction), and landslides.

Rupture of a Known Earthquake Fault
Regional faulting near the Project site is associated with the Whittier-Elsinore Fault Zone. In general, the Elinore Fault Zone trends northwest towards the Whittier Fault Zone along the base of the eastern side of the Santa Ana Mountains. As the Elsinore Fault Zone trends northward, it diverges into the Chino Fault, Main Street Fault, Eagle Fault, and Tin Mine Fault south of the Project site near Hagador Canyon. Farther to the northwest the Fresno Fault trends westward towards the Whittier Fault Zone. Generally, it is believed that that the Tin Mine Fault, Eagle Fault, and Fresno Fault transfer displacement from the Main Street Fault to the Whittier Fault Zone. (LGC, 2019b, p. 11) The Tin Mine Fault and Main Street Fault of the Elsinore Fault Zone transect the central and eastern portions of the Project site, respectively, and are depicted on Sheets 1 and 2 in the Project’s Fault Evaluation (Technical Appendix G2). These faults have been delineated as Earthquake Fault Zones in accordance with the Alquist-Priolo

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Earthquake Fault Zoning Act. In addition, mapping based on site geomorphology completed by others indicated potential “step over” faulting in the area which warranted subsurface investigation. During a prior subsurface investigation four additional faults were identified and located, Faults A through D. During LGC’s 2019 subsurface investigation an additional fault zone, possibly a splay of the Main Street Fault or “step over” fault, was encountered and ultimately denoted as Fault Zone E. Descriptions, locations, and dating of the faults encountered onsite are summarized in detail in Subsection 3.2 of the Project’s Fault Evaluation. Based on LGC’s review of the previously-performed subsurface fault investigations and the 2019 investigation conducted by LGC, it has been determined that the Tin Mine Fault, Main Street Fault, and Faults A through D are not Holocene-Active, and no setbacks from these faults are required. (LGC, 2019b, pp. 12-16) The eastern boundary of Fault Zone E is defined by a well-developed thickness of clay gouge and displaces older Trabuco Formation over younger Ladd Formation. The western boundary of the fault zone is not as well-defined (i.e. absence of well-developed fault gouge, slicken lines, polished surfaces, etc.) indicating that the majority of past displacement of Fault Zone E has occurred along or near the eastern boundary and dissipates towards the west. Due to the lack of overlying soils that could be used to date the fault and prior observations, this fault zone is considered Holocene-Active. However, LGC previously reviewed the grading plan associated with the approved TTM 36544, and determined that the fault projects through areas with cuts up to approximately 140 feet and areas of fills up to approximately 40 feet. The subject fault planes were projected up through proposed overlying fill and down through proposed cut areas to design finish grades in order to anticipate its location subsequent to grading.

LGC indicates that the projected fault rupture zone has been conservatively estimated and that the actual location of the faults subsequent to grading would be located within the limits of the projected fault rupture zone. Based on the well-defined nature of the eastern fault zone boundary, anticipated amount of displacement, and conservative projection of the fault rupture zone at finish grades, LGC recommends that habitable structures be setback a minimum of 25 feet from the limits of the projected fault rupture zone. The recommended structural/building setback was accommodated on the grading plans associated with the approved TTM 36544. (LGC, 2019b, p. 19)
The grading plan and proposed lotting associated with proposed TTM 36544R1 is consistent with the grading plan associated with the approved TTM 36544 within the portions of the Project site where Fault Zone E was conservatively mapped on site. Consistent with the approved TTM 36544, Fault Zone E would traverse cut and fill slopes near proposed on-site Streets “A” and “B.” There are ten proposed residential lots within close proximity to Fault Zone E along Streets “A” and “B,” and consistent with the project evaluated in the SHP EIR, all of the proposed homes are set back a minimum of 25 feet from the mapped fault zone (refer to Sheet 1 of 3 of the Geologic Map included in the Project’s Fault Evaluation report [Technical Appendix G2]). Accordingly, although Fault Zone E is considered Holocene-Active and could result in fault rupture over the life of the Project, because the proposed residential structures are set back more than 25 feet from the conservatively-mapped fault zone, the proposed Project would not expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving rupture of a known earthquake fault, and impacts would be less than significant. (LGC, 2019b, pp. 20-22)
Strong Seismic Ground Shaking
Consistent with the findings of the SHP EIR, the Project site is located in a seismically active area of southern California and is expected to experience moderate to severe ground shaking during the lifetime of the Project. The

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risk is not considered substantially different than that of other similar properties in the southern California area.

The Project is required to be constructed in accordance with the 2022 California Building Code (CBC), as implemented by the City of Corona. The CBC identifies design features required to be implemented to resist the effects of seismic ground motions. Additionally, the Project’s Geotechnical Report (Technical Appendix G1) includes site-specific recommendations to attenuate seismic-related hazards. With mandatory compliance to the 2022 CBC, or the applicable building code at the time of Project construction, and with implementation of the recommendations of the Project’s Geotechnical Report (as required by SHP EIR Mitigation Measures GEO-1 through GEO-23), structures and persons on the Project site would not be exposed to substantial adverse groundshaking effects. Accordingly, and consistent with the findings of the SHP EIR, impacts associated with strong seismic ground shaking would be less than significant with implementation of SHP EIR Mitigation Measures GEO-1 through GEO-23.

Seismic-Related Ground Failure, Including Liquefaction
Liquefaction is a seismic phenomenon in which loose, saturated, granular soils behave similarly to a fluid when subject to high-intensity ground shaking. Liquefaction occurs when three general conditions coexist: 1) shallow groundwater; 2) low density non-cohesive (granular) soils; and 3) high-intensity ground motion. Studies indicate that saturated, loose to medium dense, near surface cohesionless soils exhibit the highest liquefaction potential, while dry, dense, cohesionless soils and cohesive soils exhibit low to negligible liquefaction potential. In general, cohesive soils are not considered susceptible to liquefaction. Effects of liquefaction on level ground include settlement, sand boils, and bearing capacity failures below structures. Dynamic settlement of dry loose sands can occur as the sand particles tend to settle and densify as a result of a seismic event. Subsequent to rough grading the Project site soils conditions would consist of compacted artificial fill soils overlying dense bedrock. Based on the anticipated site soil conditions after grading and the lack of shallow groundwater, the potential for liquefaction is considered to be very low. Accordingly, and consistent with the findings of the SHP EIR, the Project would not expose people or structures to potential substantial adverse effects associated with seismic-related ground failure, including liquefaction, and impacts would be less than significant. (LGC, 2019a, p. 9) Landslides
LGC conducted a review of the regional geologic maps, which did not indicate the presence of landslides within or adjacent to the Project site. However, a landslide complex was encountered and mapped during a previous geologic investigation. The landslide complex is located along the eastern boundary of the site on the southern side of Kroonen Canyon. A portion of the landslide complex is located offsite east of the Project site. Subsurface exploration found the landslide to extend to depths of approximately 45 feet below existing grades within the Project site. However, the Project would be subject to compliance with SHP EIR Mitigation Measure GEO-2 (as modified/supplemented herein), which requires compliance with the Geotechnical Report’s recommendations related to removal depths. Consistent with the findings of the SHP EIR, mandatory compliance with the Geotechnical Report’s recommendations would ensure that landslide hazards do not pose a substantial risk to the proposed development and would ensure that the Project does not expose people or structures to potential substantial adverse effects associated with landslides, and would reduce the Project’s potential impacts to below a level of significance. (LGC, 2019a, pp. 7-8)

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Conclusion
Based on the site-specific geotechnical and fault investigations, and with implementation of the mitigation measures identified by the SHP EIR (as supplemented/modified herein), the proposed Project would not expose people or structures to potential substantial adverse effects associated with earthquake faults, strong seismic ground shaking, seismic-related ground failure (including liquefaction), or landslides, and impacts would be reduced to less-than-significant levels. It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. b) Would the Project result in substantial soil erosion or the loss of topsoil? Skyline Heights Project EIR Findings: Less-than-Significant Impact. The SHP EIR found that construction activities associated with buildout of the SHP would require mass grading on the site and removal of fill, alluvium, and other loose materials. The SHP EIR noted that Best Management Practices would be implemented in accordance with an approved Erosion Control Plan. After construction, the SHP EIR found that any non-paved, exposed areas would be landscaped. Therefore, the SHP EIR concluded that with compliance with applicable requirements, impacts regarding soil erosion or the loss of topsoil would be less than significant. (Corona, 2015, pp. 4.E-21 to 4.E-22) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The Project has the potential to result in substantial soil erosion or loss of topsoil during both construction and long-term operation. Each is discussed below.

Construction-Related Activities
Consistent with the information disclosed in the SHP EIR, proposed grading activities associated with the Project would temporarily expose underlying soils to water and air, which would increase erosion susceptibility while the soils are exposed. Exposed soils would be subject to erosion during rainfall events or high winds due to the removal of stabilizing vegetation and exposure of these erodible materials to wind and water.

Pursuant to the requirements of the State Water Resources Control Board, the Project Applicant is required to obtain coverage under a National Pollutant Discharge Elimination System (NPDES) permit for construction activities. The NPDES permit is required for all projects that include construction activities, such as clearing, grading, and/or excavation that disturb at least one acre of total land area. Additionally, during grading and other construction activities involving soil exposure or the transport of earth materials, CMC Chapter 15.36 (Grading Regulations) would apply, which establishes, in part, requirements for the control of dust and erosion during construction (e.g., refer to CMC Section 15.36.170, Dust Control). As part of the requirements of Chapter 15.36, the Project Applicant would be required to prepare an erosion control plan that would address construction fencing, sandbags, and other erosion-control features that would be implemented during the construction phases to reduce the site’s potential for soil erosion or the loss of topsoil. Requirements for the reduction of particulate matter in the air also would apply, pursuant to SCAQMD Rule 403. Consistent with the findings of the SHP EIR, mandatory compliance with the Project’s NPDES permit and applicable regulatory requirements would ensure that water and wind erosion impacts would be less than significant.

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Long-Term Operational Activities
Following construction, wind and water erosion on the Project site would be minimized, as the areas disturbed during construction would be landscaped or covered with impervious surfaces. Only nominal areas of exposed soil, if any, would occur in the site’s landscaped areas. The only potential for erosion effects to occur during Project operation would be indirect effects from stormwater discharged from the property. The Project would entail grading within and fill of in the unnamed and several smaller tributary streams within the Project development area, while preserving the existing drainage patterns within on- and off-site open space areas. A system of storm drain pipes are proposed to convey the runoff across the site to the designated discharge points. The drainage collection and conveyance system will be designed to convey the 100-year storm runoff. The on-site development would have a separate water quality piping system to convey the first flush runoff to designated treatment areas prior to discharge into the mainline storm drain systems. This would eliminate the comingling of development runoff with offsite runoff prior to discharge into the public storm drain system and/or existing drainage channels.

All flows generated on the Project site would be conveyed to water quality basins, which would provide water quality treatment for site runoff. The site’s runoff would be detained and desilted in these basins prior to being discharged into various existing discharge points around the site. Outlet structures have been designed for the 100-year 1-hour storm event per typical minimum flood protection criteria by Riverside County Flood Control and Water Conservation District (RCFCWCD) criteria. This criteria is more stringent than the California Code of Regulation Section 3706 (CCR 3706) design criteria for 20-year 1-hour storm event. The Project’s site-specific Hydrology and Hydraulic Drainage Report (Technical Appendix H1) demonstrates that following Project construction the total volumes would be mitigated to the pre-development conditions. In addition, the Project Applicant is required to prepare and submit to the City for approval a Project-specific Water Quality Management Plan (WQMP) for long-term operations. The WQMP must identify and implement an effective combination of erosion control and sediment control measures (i.e., Best Management Practices) to reduce or eliminate discharge to surface water from storm water and non-storm water discharges. Adherence to the requirements noted in the Project’s required WQMP (refer to Technical Appendix H2) would further ensure that potential erosion and sedimentation effects would be less than significant. As such, the Project would not result in a substantial increase in runoff that could result in increased erosion hazards downstream. Impacts would be less than significant. (KWC Engineers, 2025a, pp. 5-8)
Conclusion
Based on the preceding analysis, the proposed Project would not result in substantial soil erosion or the loss of topsoil during near-term construction activities or long-term operation, and impacts would be less than significant.

It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR. c) Would the Project 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?
Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that mass grading at the SHP site has the potential to reduce slope stability and result in settling ad other

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geologic hazards. However, the SHP EIR noted that adherence to the design and remedial grading and monitoring recommendations of the Geotechnical Report, as required by Mitigation Measures GEO-1 through GEO-15, would reduce such impacts to less-than-significant levels. (Corona, 2015, pp. 4.E-22 to 4.E-25) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The Project’s potential to result in significant impacts associated with on- or off-site landslide, lateral spreading, subsidence, liquefaction, and collapse is discussed below.

On- and Off-Site Landslides
The Project site is located on a hillside that contains fairly steep topography. Thus, there is a potential for future grading to result in conditions on site that are conducive to landslide hazards. The SHP EIR determined that the approved TTM 36544 would result in maximum depths of cut and fill of 130 feet and 138 feet, respectively.

Consistent with the project evaluated in the SHP EIR, the Project’s grading plan proposes cuts and fills to maximum design depths of approximately 132.0 feet (vicinity of Lot 135) and 131.4 feet (vicinity of Lot 15), respectively. All proposed slopes within the development would be constructed at a gradient of 2:1 (horizontal:vertical) and would be constructed in accordance with the site-specific recommendations contained within the Project’s geotechnical report (Technical Appendix G1), as required by SHP EIR Mitigation Measures GEO-1 through GEO-9. Mandatory compliance with SHP EIR Mitigation Measures GEO-1 through GEO-9, which implement the recommendations contained within the Project’s geotechnical report with respect to grading/slope stability, would ensure that all proposed slopes are engineered and constructed to maximize stability and preclude safety hazards to on-and offsite areas. As such, and consistent with the conclusion reached by the SHP EIR, the Project would result in lessthan-significant impacts associated with on- or off-site landslides.

Lateral Spreading
Lateral spreading is a type of liquefaction-induced ground failure associated with the lateral displacement of surficial blocks of sediment resulting from liquefaction in a subsurface layer. Once liquefaction transforms the subsurface layer into a fluid mass, gravity plus the earthquake inertial forces may cause the mass to move downslope towards a free face (such as a river channel or an embankment). Lateral spreading may cause large horizontal displacements and such movement typically damages pipelines, utilities, bridges, and structures. Due to the extremely low potential for liquefaction, the potential for lateral spreading is also considered to be very low.

Accordingly, and consistent with the finding of the SHP EIR, the proposed Project would not 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 lateral spreading, and impacts would be less than significant.

Subsidence and Collapse
Subsidence due to earthwork equipment is expected to be up to approximately 0.1-foot in the older artificial fill areas. These values are estimates only and exclude losses due to removal of vegetation or debris. Fill soils are subject to post-grading settlement. This even occurs to properly compacted fill soils with properly constructed subdrains. Total fill depths greater than approximately 50 feet require surface settlement monitoring be performed after grading is completed to ensure long-term fill settlement is within tolerable limits prior to commencement of building construction. Pursuant to the recommendations of the Project’s Geotechnical Report and as required by the mitigation measures from the SHP EIR, settlement monuments would be installed promptly after grading in

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order to monitor settlement of deeper fills (approximately 50 feet or deeper) in accordance with the details provided in Appendix E to the Project’s Geotechnical Report. The precise locations of the settlement monuments would be verified or adjusted based on the actual as-graded fill depths. At the completion of their construction, the monuments would be surveyed by a licensed surveyor to a fixed offsite benchmark (read at three locations) to an accuracy of at least 0.01- foot with provided measurements to 0.001-foot. When site grading is completed, the monuments would then be monitored periodically at regular intervals (eight times in each of the first two months, twice in the third month, and then once a month until informed otherwise by the Project geologist). The readings would be provided to the Project geologist, which would continue monitoring settlement until total settlements are within tolerable limits. Accordingly, with mandatory compliance with the mitigation measures from the SHP EIR requiring compliance with the recommendations of the Project’s Geotechnical Report, the Project would not 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 subsidence hazards. Consistent with the conclusion reached by the SHP EIR, impacts would be less than significant following mitigation.

Liquefaction
Liquefaction is a seismic phenomenon in which loose, saturated, granular soils behave similarly to a fluid when subject to high-intensity ground shaking. Liquefaction occurs when three general conditions coexist: 1) shallow groundwater; 2) low density non-cohesive (granular) soils; and 3) high-intensity ground motion. Studies indicate that saturated, loose to medium dense, near surface cohesionless soils exhibit the highest liquefaction potential, while dry, dense, cohesionless soils and cohesive soils exhibit low to negligible liquefaction potential. In general, cohesive soils are not considered susceptible to liquefaction. Effects of liquefaction on level ground include settlement, sand boils, and bearing capacity failures below structures. Dynamic settlement of dry loose sands can occur as the sand particles tend to settle and densify as a result of a seismic event. Subsequent to rough grading the soils conditions at the Project site would consist of compacted artificial fill soils overlying dense bedrock. Based on the anticipated site soil conditions after grading and lack of shallow groundwater, the potential for liquefaction is considered to be very low. Accordingly, and consistent with the findings of the SHP EIR, the proposed Project would not 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 liquefaction hazards, and impacts would be less than significant.

Conclusion
With mandatory compliance with the site-specific recommendations contained in the Project’s Geotechnical Report (Technical Appendix G), as required by the mitigation measures presented in the SHP EIR (as supplemented/modified herein), the proposed Project would not 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, and impacts would be reduced to less-than-significant levels. It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

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d) Would the Project be located on expansive soil, as defined in 1803.5.3 of the California Building Code (2022), creating substantial risks to life or property? Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that on-site soils are anticipated to have low to medium expansion potential. The SHP EIR further noted that any soils with high or critical expansion potential would be replaced with compacted fill with low or medium expansion potential as required by SHP EIR Mitigation Measure GEO-10. The SHP concluded that the design of foundations to meet medium soils expansion potential, as required by SHP EIR Mitigation Measure GEO-10 would reduce risks to life or property to a less-than-significant level. (Corona, 2015, p. 4.E-25) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Based on the results of previous laboratory testing by others as part of prior geotechnical investigations, fills at the completion of grading are anticipated to have a “Very Low” to “Medium” expansion potential. However, excavation of some portions of the Holz Shale and/or Silverado Formation could result in expansion potentials ranging from “High” to “Very High”.

However, the Project would be required to implement the recommendations of the Project’s Geotechnical Report (Technical Appendix G), as required by the mitigation measures presented in the SHP EIR (as supplemented/modified herein), which include recommendations to address potential impacts associated with expansive soils. With implementation of the Geotechnical Report recommendations, the proposed Project would not be located on expansive soil, as defined in 1803.5.3 of the California Building Code (2022), creating substantial risks to life or property, and impacts would be reduced to less-than-significant levels. It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.
e) Would the Project have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water? Skyline Heights Project EIR Findings: No Impact. The SHP EIR found that the SHP project would be served by the City’s wastewater system, and that sewer infrastructure (i.e., pipes) would be installed to accommodate the proposed expansion. The SHP EIR concluded that no significant impact would occur with regard to soils supporting septic tanks or alternative wastewater disposal systems. (Corona, 2015, pp. 4.E-25 to 4.E-26) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. Consistent with the findings of the SHP EIR, with implementation of the Project, sewer service to the Project site would be provided by the City of Corona Utilities Department via proposed sewer lines within the Project site that would connect to existing sewer mains located within Mabey Canyon Road, Border Avenue, and Trudy Way. Accordingly, because the Project does not include the use of septic tanks or alternative wastewater disposal systems, no impact would occur. It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Therefore, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

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f) Would the Project conflict with an applicable plan, policy, or regulation adopted for purposes of avoiding or mitigating physical impacts associated with geology and soils? Skyline Heights Project EIR Findings: Less-than-Significant Impact With Mitigation Incorporated. The SHP EIR found that the SHP project would comply with all requirements related to seismic and geologic hazard safety standards. The SHP EIR further found that the SHP project would not conflict with an applicable plan, policy, or regulation adopted for the purpose of avoiding or mitigating physical impacts associated with geology and soils, and that any impacts would be reduced to less-than-significant levels with implementation of SHP EIR Mitigation Measures GEO-1 through GEO-23. (Corona, 2015, pp. 4.E-25 to 4.E-26) EIR Addendum No. 1 Finding: No Substantial Change from Previous Analysis. The Project would comply with all applicable requirements related to seismic and geologic hazard safety standards, as established by local, state, and federal regulations. The previously certified SHP EIR determined that the Project would adhere to all relevant plans, policies, and regulations adopted for the purpose of avoiding or mitigating physical impacts associated with geology and soils. Additionally, the Project would implement the applicable mitigation measures from the SHP EIR (GEO-1 through GEO-23), which are designed to address potential geologic and soil-related impacts. These measures would ensure that any potential impacts are reduced to a less-than-significant level. Furthermore, the discussion presented below in Table 23, Project Consistency with General Plan Policies Related to Seismic and Geologic Hazards, demonstrates that the proposed Project would be fully consistent with all applicable General Plan policies related to Geology and Soils. Therefore, the Project would not conflict with any applicable plans, policies, or regulations intended to mitigate or avoid physical impacts related to geology and soils. It also bears noting that the proposed Project would develop the same property as the Approved Project, and there has been no changed circumstances that would affect geotechnical impacts. Accordingly, the proposed Project would not result in any new impact not already analyzed in the SHP EIR or increase the severity of a significant impact previously identified and analyzed in the SHP EIR.

Table 23 Project Consistency with General Plan Policies Related to Seismic and Geologic Hazards
Goal/Policy Project Consistency
Goal PS-1:Adequate protection of the health, safety, and welfare of the public, property and economic investments, and community social and service functions from seismic and geologic events.

Consistent. As documented herein and in Subsection 4.E of the SHP EIR, the Project would be required to comply with the site-specific recommendations of the Project’s
Geotechnical Report (Technical Appendix G1), pursuant to the mitigation measures included in the SHP EIR (as
supplemented/modified herein), as well as the CBC, which would ensure that future Project residents are adequately protected from seismic and geologic events.

Policy PS-1.1: Maintain accurate records, information, and mapping of seismic and geologic activity and hazards in Corona and the region from the California Geologic Survey; update records with information from local geotechnical studies.

Not Applicable. Policy PS-1.1 provides direction to City staff and decision makers to maintain records and
information related to seismic and geologic activity
monitoring, and is unrelated to the proposed Project.

Policy PS-1.2 In areas subject to seismic and geologic
hazards, require development proposals to include a
geotechnical hazard analysis and specific mitigations to Consistent. As noted in the analysis provided herein and in the SHP EIR, the Project would be required to comply with the site-specific recommendations of the Project’s

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Goal/Policy Project Consistency
reduce risks to acceptable levels as a condition of approval. Geotechnical Report (Technical Appendix G1), pursuant to the mitigation measures included in the SHP EIR (as
supplemented/modified herein), as well as the CBC, which would ensure that the Project includes appropriate
measures to reduce geologic hazard risks to acceptable
levels.

Policy PS-1.3 Enforce development requirements, such as seismic study analyses, project siting, setbacks, and project design features for proposed developments near the
Elsinore Fault Zone and other active faults in accordance with the Alquist-Priolo Act.

Consistent. As noted under the discussion of Geology and Soils Threshold a), the Project has been designed to
incorporate appropriate setbacks from Fault Zone E, and no structures are proposed within any active fault zones.

Policy PS-1.4 Require adherence to the latest California Building Codes and associated regulations in the City’s Municipal Code; update local codes and development
requirements periodically for the latest best practices.

Consistent. The Project would be subject to compliance
with the CBC, as implemented by CMC Chapter 15.36
(Grading Regulations). The remaining portions of this
policy provide direction to City staff and decision makers, and is unrelated to the proposed Project.

Policy PS-1.5 Locate new or existing buildings in the
Elsinore earthquake fault zone or in other areas at risk from liquefaction, landslides, or other seismic and geologic hazards in the community and take corrective actions to minimize the risk of loss.

Consistent. The Project has been designed to implement
the site-specific recommendations of the Project’s
Geotechnical Report (Technical Appendix G1), and would
be required to implement the recommendations identified by the Geotechnical Report pursuant to the mitigation
measures presented in the SHP EIR (as supplemented/
modified herein), which would reduce to a level below
significance potential adverse effects associated with
liquefaction, landslides, or other seismic and geologic hazards.

Policy PS-1.6 Identify vulnerable structures and encourage the retrofit or upgrade of vulnerable buildings (e.g., mobile homes) to minimize the damage to structures and reduce
the risk or injury or death from seismic or geologic events.

Not Applicable. Policy PS-1.6 provides direction to City staff and decision makers, and is unrelated to the proposed Project.

Policy PS-1.7 Require geotechnical analysis for projects proposed in areas subject to corrosive soils. Where found, require appropriate cathodic protections and other best practices to minimize damage to buildings, structures, and infrastructure.

Consistent. A Geotechnical Report was prepared for the
Project and is included as Technical Appendix G1. Pursuant to the SHP EIR mitigation measures (as modified/
supplemented herein), the Project would be required to
implement all of the recommendations included in the
Geotechnical Report, which would serve to preclude
damage to buildings, structures, and infrastructure.

Policy PS-1.8 Limit grading for developments to the
minimum needed to preserve natural topography, preserve vegetation, and maintain soil and slope stability. Require appropriate grading plans and slope stability to minimize soil instability.

Consistent. The proposed Project consists of the first
revision to TTM 36544, and has been designed to reduce
the amount of grading required on site. Areas proposed
for disturbance as part of the Project would be
substantially reduced from 170.70 acres under the
Approved Project to 151.8 acres under the proposed
Project. All grading proposed on site is the minimum
amount of grading necessary to preserve natural
topography, preserve vegetation, and maintain soil and

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Goal/Policy Project Consistency
slope stability, while accommodating the proposed
development.

Mitigation Measures
The following mitigation measures from the SHP EIR shall apply and, consistent with the findings of the SHP EIR, would reduce the Project’s potential impacts to geology and soils to below a level of significance.

GEO-1 Site Preparation and Removals. All grading shall be accomplished under the observation and testing of the Project Geotechnical Engineer and Engineering Geologist in accordance with the recommendations contained in the Project Geotechnical Report, contained in Appendix F of this Draft EIR, the current codes practiced by the City of Corona and the Earthwork Specifications contained in Appendix IV of the Project Geotechnical Report.

Loose, compressible residual soil, non-engineered onsite fill, colluvium, alluvium, landslide debris, older alluvium and weathered bedrock shall be removed from fill areas prior to placement of fill and shall be removed from shallow cut areas, where exposed at finish grades. Guidelines to determine the depth of removals are presented below; however, the exact extent of the removals must be determined in the field during grading, when observation and evaluation of the greater detail afforded by those exposures can be performed by the Geotechnical engineer and/or Engineering Geologist.

The minimum backcut ratio shall be 1:1 (horizontal to vertical). The bottoms of all removal areas shall be observed, mapped and approved by the Engineering Geologist prior to fill placement. It is recommended that the bottoms of removals be surveyed and documented by the Project Civil Engineer.

Groundwater, if encountered during grading, shall be evaluated by the Geotechnical Engineer and/or Engineering Geologist. In general, groundwater is not anticipated to adversely affect grading although saturated soils and free water may be encountered along canyons and within alluvium removals. If groundwater is excessive, remedial measures such as horizontal drains or under drains may need to be installed. Further, settlement monuments and plates (see Plate VI of the Geotechnical Report) shall be installed during and after completion of grading to monitor settlement monuments and plates shall be used to determine when the majority of the primary settlement has been completed to allow for the release of affected lots for construction.  Stripping: Vegetation, debris and other deleterious materials are unsuitable as structural fill material and shall be disposed of offsite prior to commencing removals and placement of compacted fills. The thick, natural vegetative growth onsite is significant and will require consideration for removal. An onsite mulching operation may be considered. The mulched materials could then be used in future landscape areas.  Soil and Weathered Bedrock (unmapped): Loose, compressible onsite soils and underlying weathered bedrock shall be removed to expose the underlying competent bedrock materials prior to placement of compacted fill and when exposed in shallow cut area. An average removal depth of 5 feet is anticipated for removal of topsoil and weathered bedrock. In

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general, onsite soils and weathered bedrock are suitable to be re-used as structural fill when properly moisture-conditioned.
 Undocumented Artificial Fill (locally mapped as AFu): Fills associated with "recreational" grading, construction of unpaved access roads, mining operations and existing trench backfill shall be removed prior to fill placement. Generally, these artificial fills range from a depth of 3 to 20 feet. Local areas of undocumented fill associated with previous geotechnical investigations are not plotted on the map. Other fills, including roadway fills and trench backfill, are not mapped due to their localized extent and minor thickness. Removals shall extend below the undocumented fill until competent materials are encountered.  Alluvium/Colluvium (map symbol Qal): All alluvium deposits exposed at existing or cut grades shall be entirely removed prior to fill placement. These deposits range in thickness from approximately 5 feet to 35 feet. Ginter and Associates recommends that all alluvial and colluvial soils below proposed fill areas and in cut areas be removed to expose competent bedrock or terrace deposits. Anticipated average removal depths for alluvium/colluvium areas are expected to vary to an estimated maximum thickness of 35 feet.  Groundwater was not encountered during PSE's subsurface investigation within the alluvium onsite. However, access was limited and certain alluvial areas could not be investigated such as within Krooner Canyon. If "saturated" alluvium is encountered that possesses a degree of saturation of 85% of more and is consistent with depth to bedrock, consideration may be given to leaving the saturated alluvium in-place, provided that settlement time-delay consequences are acceptable to the owner. If saturated alluvium is encountered and is going to remain inplace, an additional liquefaction investigation may be required and dynamic settlement recommendations for those areas will likely change.
 Older Alluvium (Qoa): All older alluvium shall be removed to expose the underlying competent bedrock. Generally, these deposits range in depth from 10 to about 20 feet.  Landslide Debris (Qls): All landslide debris that could adversely affect the proposed development shall be removed to expose the underlying competent bedrock. Generally, these deposits range in depth from 10 to about 29 feet, but may range up to around 35 feet in depth.  Removals Along Grading Limits: Removals of unsuitable soils shall be required prior to fill placement along the grading limit. A 1:1 projection, from toe of slope or grading limit, outward to competent materials shall be established, when possible. Where removals are not possible due to grading limits, property line or easement restrictions, removals shall be initiated at the grading boundary (property line easement, grading limit or outside the improvement) at a 1:1 ratio inward to competent materials. Where this reduced removal criterion is implemented, special maintenance zones may be necessary. Affected areas shall be established, minimally, as a 1:1 projection from suitable removal bottom to finish ground surface. This condition is mainly expected in the slope areas. Where the projection intersects the face of the slope, the potential for distortion of the slope in response to post-grading settlements exists and provisions for future maintenance of such slopes shall be provided.

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GEO-2 Slope Stability and Remediation
 Cut Slopes: The majority of cut slopes have been designed at a slope ratio of 2:1. The Engineering Geologist shall observe cut slopes and cut slope stabilization backcuts during grading. Modifications to the recommendations presented herein will likely be required based upon conditions exposed by grading.
 Williams Formation (KW): Cut slopes within the Williams Formation may expose adverse bedding that shall require remediation. The cut slope superjacent to Lots 278 and 279 is anticipated to require replacement with a buttress fill. Probable buttresses are anticipated for the cut slope above Lots 261 through 267 and the cut slope below the WQMP Basin and Lots 247 through 255, as depicted on Figure 1 and Figure 2 (pocket) of the Geotechnical Report.  Ladd Formation: Cut slopes within the Ladd Formation may expose adverse bedding that shall require remediation. The majority of the cut slopes should expose bedding dipping into the slope or at an angle steeper than the proposed cut slopes (greater than 60 degrees). Cut slopes within the Ladd Formation that expose bedding dipping into the slope or at an angle steeper than the proposed cut slopes are expected to be grossly stable; however, the final determination shall be made based on exposed conditions during grading. Cut slopes within the Ladd Formation may expose conglomerate resulting in poorly cemented sands, cobbles and boulders at finish grade, producing a rough uneven surface. These cut slopes shall be evaluated in the field by the Project Engineering Geologist or Geotechnical Engineer.

Replacement of those slopes with compacted stabilization fills may be required. Future exploration and in-grading observation could reveal more favorable geology in these specific areas.
 Alluvium/Colluvium: Cut slopes exposing alluvial/colluvial soils (Qal) shall require replacement with a drained stabilization fill. Typically, such corrective grading would be constructed with a minimum key width corresponding to one-half the full height of the superjacent slope, but not less than 15 feet. Minimum key depths at the toe shall be 2 feet.

All stabilization fills shall be provided with a backdrain and outlet system as detailed in Appendix IV of the Geotechnical Report.
 Silverado Formation: Cut slopes within the Silverado Formation are expected to be grossly stable; however the final determination shall be made based on exposed conditions during grading. Cut slopes within the Silverado Formation may expose poorly cemented sands, cobbles and boulders at finish grade, which would produce a rough uneven surface. These cut slopes shall be evaluated in the field by the Project Engineering Geologist or Geotechnical Engineer. Replacement of those slopes with compacted stabilization fills may be required.  Fill Slopes: The majority of fill slopes on the project are designed at a maximum slope ratio of 2:1. The highest fill slope is approximately 160 feet in height and located subjacent to Lot 68.

Based on the results of the calculations, the 2:1 fill slopes 160 feet and less in height, when properly constructed with onsite materials, are expected to be grossly stable, as designed.

Keys shall be constructed at the toe of all fill slopes where unsuitable soil removals do not accomplish a minimum key width of one-half the slope height plus bench widths or twenty (20) feet, whichever is greater. Minimum key depths at the toe shall be 2 feet. Due to grading

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limit restrictions, removals of unsuitable soils beyond the proposed toe may be limited; therefore, additional slope maintenance shall be expected in the areas where a 1:1 projection into approved materials cannot be achieved.

GEO-3 Subsurface Drainage. Canyon subdrains are proposed as depicted on Figures 1 through 7 of the Geotechnical Report and shall consist of 6-inch and 8-inch diameter pipes and shall be constructed in accordance with the details shown in Appendix IV of the Geotechnical Report. Final determination of drain locations shall be made in the field. Outletting of subdrain systems shall require coordination with the Project Civil Engineer in determining suitable facilities to accept to drain water.

GEO-4 Overexcavation. Where a transition of cut and fill occurs across a finished lot, it shall be necessary to overexcavate the bedrock portions and replace it with compacted fill. The depth of bedrock overecavation shall be equal to 1/3 the maximum fill depth (after removals) on the fill side of the transition. Anticipated transition lots are shown on figures 1-7 of the geotechnical report. Cut pads shall be overexcavated a minimum of 5 feet to provide a uniform foundation material. Some highly expansive soils of the Silverado Formation may be encountered at grade in some areas.

Consideration shall be given to increasing the overexcavation depth to mitigate for highly expansive soils, if warranted. Difficult excavation with a backhoe can be expected in some street areas. Ginter & associates recommends street overexcavation and replacement with compacted fill to facilitate utility emplacement in these street areas and driveways. Depths of overexcavation shall extend one (1) foot below the deepest utility line.

GEO-5 Fill Materials. Excavated on-site soils may be used as compacted fill. The fill materials to be used as compacted engineered fill shall be free of organics, debris, deleterious materials, and rocks over 6 inches maximum dimension, and must be approved by the project geotechnical engineer or project geologist prior to use. Import soils, if required, shall be evaluated by the project geotechnical engineer for suitability prior to delivery. Import soils shall be free of trash, debris or other objectionable materials. All import fill shall have engineering characteristics similar to the on-site soils.

GEO-6 Fill Placement, Moisture Conditioning, And Compaction. After approval of the over-excavation and prior to placement of any compacted engineered fill materials, the exposed removal bottoms shall be scarified to a minimum depth of six (6) inches. The area shall then be moisture conditioned approximately 1 to 2 percentage points above the optimum moisture content, and compacted to a minimum of 90 (or 93) percent of the applicable maximum density. The planned development will involve deep fills in the canyon areas and side-hill fill slopes. In order to reduce the amount of fill settlement, the fill shall be compacted to the minimum relative compaction shown below:

Fill Depth (Feet) Minimum Relative Compaction (ASTM: D1557) (%) 0 – 50 90
Below 50 93
Fill slopes shall also be constructed at the minimum relative compactions shown above, with the exception of the outer 3 feet of the slope face which can be placed at 90% relative compaction.

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Deep fill areas requiring 93% relative compaction are delineated in Plate VI of the Geotechnical Report.

Generation of oversized rock (over 8 inches in maximum dimension) from excavations in the bedrocks is anticipated. Oversize rock shall be placed in single file windrows not exceeding three feet in height and six (6) feet in width with a minimum equipment width (15 feet) separating each windrow or a rock blanket fill not exceeding two (2) to three (3) feet in height. Large erratic rocks shall be buried individually. Granular fill shall be thoroughly flooded in the rock voids and covered with a minimum two feet compacted fill blanket. Successive windrows shall be staggered and none shall be placed within 10 feet of finished grade or closer than 15 feet to compacted fill slope surfaces. Typical rock placement construction detail is provided in Appendix IV of the Geotechnical Report. Placement of rock windrows shall be performed under the observation and recommendations of the Project Geotechnical Engineer.

Fill materials shall be spread in thin lifts, moisture conditioned to about 1 to 2 percentage points over optimum moisture content and compacted to a minimum of 90 (or 93) percent of the laboratory maximum dry density as determined in accordance with ASTM Test Method D-1557.

Each lift shall be treated in a like manner until the desired finished grades are achieved. The grading contractor shall have suitable and sufficient compaction equipment in operation to achieve the required compaction. When necessary, earthmoving equipment may be utilized for compaction or temporarily halted in order to permit adequate compaction of fills.

GEO-7 Slope Construction

1. Care shall be taken during grading to prevent spillage of loose materials over slopes to remain natural. Should loose soil be spilled onto natural slopes by the grading contractor, removal of the loose fill shall be required.

2. Fill shall be properly benched into firm bedrock or compacted fill as directed by the Project Engineering Geologist and/or Geotechnical Engineer during grading. Typical benching shall include 4-foot verticals exposing approved, competent material (see Appendix D – Typical Benching Detail of the Geotechnical Report).

3. In order to minimize surficial slumps on compacted fill slopes, the following grading procedures shall be used:
a) Where possible, fill slopes shall be constructed by overfilling a minimum of three (3) horizontal feet and then trimming back to expose the dense inner core of the slope surface. Compacted fill slopes shall be back-rolled during construction at intervals not exceeding four (4) vertical feet. Care shall be taken to construct the slope in a workmanlike manner so that it is positioned at its designed orientation and slope ratio. Achieving a uniform slope surface by subsequent thin wedge filling must be avoided. Any add-on correction to a fill slope shall be done by overfilling the affected area in horizontal, compacted lifts which must be benched into the existing fill prism. The overfilled slope may then be trimmed to the design gradient.
b) Where fill slopes are planned above natural slopes and cannot be overfilled and trimmed back, the slopes shall be rolled for the entire height of the slope with a sheepsfoot roller

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and then finished with a grid roller. If the desired compaction is not obtained in this manner, a vibratory sheepsfoot roller may be required. To be most effective, this equipment shall be anchored and manipulated from a side-boom tractor. In lieu of a grid roller, the slope may be track rolled with a John Deere 450, Caterpillar D-8 dozer or equivalent. To obtain the required compaction and appearance of the slope face, the soil moisture shall be maintained at above optimum from the time of mass filling to the completion of grid rolling.
c) The grading contractor shall take proper care to avoid spillage of loose material down the face of the slopes during grading and during drainage terrace and down-drain construction. Fine grading operations for benches and down-drains shall not deposit loose trimmed soils on the finished slope surfaces. Loose soil materials shall require removal. d) Seeding and planting of slopes shall proceed as rapidly as possible to achieve a wellestablished and deep-rooted vegetal cover requiring minimal watering. The type of vegetation and watering schedule shall be established by a landscape architect familiar with hillside maintenance.

GEO-8 Earthwork Observations And Testing
a) The site preparation, over-excavation, and earthwork shall be performed under the observation and testing by a representative of the Project Geotechnical Engineer or Project Geologist. b) The fill shall be tested at the time of placement to verify that the required compaction is achieved. c) The fill compaction shall be determined in the field by the Sand Cone Method (ASTM: D 1556) or Nuclear Gauge Method (ASTM: D 2216), or other test method approved by the Project Geotechnical Engineer.
d) During grading, an adequate number of field density tests shall be performed using approved test procedures in order to determine compliance of earthwork to the project requirements. The frequency of field density testing shall be in accordance with the recommendations of the Project Geotechnical Engineer.
e) Quality control testing performed to determine the acceptability of the fill compaction shall be based on the laboratory maximum dry density and optimum moisture content determined in accordance with ASTM: D 1557 test procedure.
f) Any surface or subsurface obstructions, or questionable materials encountered during grading shall be brought immediately to the attention of the Project Geotechnical Engineer. Deeper excavations may be required, should unsuitable soils be encountered locally, as determined by the Project Geotechnical Engineer and/or Project Geologist.

GEO-9 Deep Fill Settlement Monitoring. In deep fill areas, settlement monuments shall be installed and periodically surveyed by the project civil engineer to evaluate the magnitude and progress of settlements. Ginter & associates proposes positioning settlement monuments at strategic locations in the deeper fill areas as shown on figure vi of the geotechnical report. These shall be monitored on a regular basis until the primary settlement has stabilized before those areas released for construction.

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GEO-10 Foundation Design. The compacted engineered fill at the project site is anticipated to be low to medium soil expansion potential. Presented below are preliminary geotechnical criteria for design of building foundations, based on medium soil expansion potential for the on-site soils:

Option 1 - Conventional Footing:

Allowable Bearing Pressure (1) = 1,500 pounds per square foot (psf) Minimum Footing Depth (2) = 24 inches
Minimum Footing Width = Continuous: 12 inches
Isolated: 24 inches
Passive Soil Pressure (3) = 250 psf/ft.

Friction Coefficient = 0.30 (ultimate)
Minimum Footing Reinforcement = Four No. 4 bars, 2 each at top and bottom Garage Door Grade Beam = 18 inches deep, Four No. 4 bars, Two each at top and bottom, tied into foundation elements

1. The above value may be increased 250 psf for each additional foot exceeding the minimum embedment depth and/or width, subject to a maximum of 2,500 psf. Allowable bearing pressures may be increased by one-third for short term loading due to wind or seismic forces.

2. Footing depth is from lowest adjacent finished soil grade. Footings shall be deepened, as necessary, to provide setback distance from adjacent slope in conformance with CBC criteria.

3. Value applies to level soil condition, and is subject to a maximum of 2000 psf.

Option 2 – Post-Tensioned Foundation:

If post-tensioned slab/footing system is selected for the subject project, the design may be based on the geotechnical criteria shown below for medium soil expansion potential. These are based on the guidelines presented in the PTI, Third Edition design manual.

Thornthwaite Moisture Index = -20
Equilibrium Suction = 3.6
Edge Lift Moisture Variation Distance, em = 5.1 feet
Edge Lift, ym = 1.1 inches
Center Lift Moisture Variation Distance, em = 9.0 feet
Center Lift, ym = 0.47 inches
Minimum Footing Depth (Exterior) = 18 inches below adjacent grade The above foundation criteria are based on medium soil expansion consideration only. Foundation design shall consider anticipated post-construction settlements, as appropriate. Foundation design details such as slab thickness, concrete strength, reinforcements, etc. shall be established by the Project Structural Engineer considering medium soil expansion and settlement potential provided below.

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GEO-11 Foundation Settlement. Total static and differential post-construction settlements for footings designed and constructed in accordance with the criteria given below and supporting loads not exceeding the typical loadings for residential construction (column and wall loads on the order of 30 kips and 3 kips/lineal foot, respectively) are not anticipated to exceed the values shown below.

The settlement estimates shall be confirmed based on review of the foundation plans. Structures shall be designed for the following post-construction settlements:
- Total settlement = 1 inch
- Differential settlement = ¾-inch (*)
(*) Between similarly loaded column footings and for continuous footings and slabs over a distance of approximately 30 feet.

General Remarks:
i. Footing depths shall not be allowed to be affected adversely, such as through erosion softening, digging, landscaping, etc.
ii. Where foundations encroach closer than five (5) feet horizontally from the flow line of drainage swales, the footing shall be deepened sufficiently to maintain the required embedment depth below the adjacent flow line.
iii. Foundation details such as concrete strength, reinforcements, etc. shall be established by the Project Structural Engineer, considering the loading and medium soil expansion potential. The footing and slab reinforcements recommended in the Geotechnical Report are minimum requirements. More restrictive criteria based on structural design considerations or Code requirements shall govern.
iv. Foundation excavations shall be observed and approved by the Project Geotechnical Engineer prior to the placement of reinforcement or concrete. Forming of footing excavations may be required. Excavations shall be free of slough and debris and thoroughly moisture conditioned prior to placing concrete.

Excavated material from footing and utility trenches shall not be placed in slab-on-grade areas unless properly compacted and tested.

GEO-12 Slab-On-Grade.

Recommended Minimum Criteria For Slab-On-Grade Are Shown Below:

Concrete Floor Slabs: Concrete floor slabs shall be 5 inches thick (minimum) and shall be reinforced with No. 3 bars at 18 inches on center, each way at mid height. No. 3 bars at 18 inches on center shall be provided connecting floor slabs to footings. In order to minimize migration of moisture up the concrete slab from soil subgrade and damage to floor coverings, a moisture barrier/water vapor retarder is recommended beneath floor slabs as discussed hereinafter.

Moisture/Water Vapor Retarder for Concrete Slab-on-Grade: In order to reduce the potential for moisture/water vapor migration up through the slab and possibly affecting floor covering, a moisture/vapor retarder is recommended under concrete floor slab-on-grade. The moisture barrier shall be properly installed, lapped and sealed in accordance with the manufacturer’s

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specifications. Punctures and rips shall be repaired prior to placement of sand. At a minimum, this moisture/water vapor retarder shall consist of 10- millimeter thick polyethylene (“Visqueen”), lapped and sealed, and placed mid-height within a 4-inch coarse sand layer. This moisture/water vapor retarder shall be installed in accordance with manufacturer’s specifications. The following recommendations are based on the tentative guidelines by the American Concrete Institute (ACI, April 2001) to reduce the potential moisture/water vapor intrusion in concrete slab-on-grade.

Based on Ginter & Associates’ review of available literature, it appears that the ACI procedure would be more effective to help reduce potential moisture/water vapor migration up through concrete slab-on-grade.

Recommendations based on the ACI guidelines are presented below:
 The moisture/water vapor retarder shall consist of high strength polyethylene membrane and shall meet or exceed the ASTM: E-1745-97 Class C material requirements for water vapor permeance, tensile strength and puncture resistance. The vapor retarder shall consist of “Moistop Plus” (Fortifiber Building Products Systems) or “Vapor Block” VB 15 (Americover, Inc.), or approved equal. The vapor retarder shall be underlain by a capillary break comprised of minimum 4 inches thick pea gravel layer. The gravel layer shall be placed and compacted on approved soil sub-grade.
 The membrane shall be placed on approved gravel layer and properly lapped and sealed.

Membranes intersecting utility pipes, sewer lines, ducts or drains shall be properly wrapped around the penetrations and sealed. All punctures and rips in the membrane shall be repaired prior to placement of concrete, following manufacturer’s recommendations. The vapor retarder shall be installed in general accordance with the procedures outlined in ASTM: E1643, and in conformance with the installation procedures recommended by the manufacturer.
 To minimize slab curling, a low slump concrete (low shrinkage mix design) shall be used for the slab construction, as determined by the Project Structural Engineer.  The moisture/water vapor protection for concrete slab-on-grade shall be selected based on cost and construction considerations, and considering potential future problems resulting from improper and uncontrolled landscape irrigation practices. Regardless of the moisture/water vapor retarder option selected, it should be emphasized that proper control of irrigation and landscape water adjacent to the structure is of paramount importance.

GEO-13 Driveways. Driveway concrete slabs shall be 5 inches thick (minimum) with no. 3 bars at 18 inches on center, each way at mid-height. The slab may be placed directly on properly prepared subgrade. No moisture barrier is required under driveway slabs.

GEO-14 Exterior Flatwork. Exterior concrete flatwork (e.g. Sidewalks, walkways) shall be 4 inches thick (minimum), with no. 3 bars at 24 inches on center, each way at mid-height and placed on properly prepared sub-grade. Hardscape areas within two feet of the descending slopes shall include a thickened edge deepened to provide a minimum five (5) feet horizontal setback between the bottom outside face of the thickened edge and slope face.

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GEO-15 Sub-Grade Pre-Saturation. Prior to concrete placement, the soil sub-grade shall be thoroughly wetted to about 12 inches in depth at a moisture condition of about 2 to 3 percentage points above the optimum moisture content.

GEO-16 General. Interior floor slabs and exterior concrete flatwork, including driveway, shall be properly designed for the construction and service loading conditions, potential settlements and soil expansion. The structural details, such as slab thickness, concrete strength, reinforcing criteria, joint spacing, etc. Shall be established by the project structural engineer. The recommended minimum reinforcements for concrete slabs provided above are intended for preliminary design only. More restrictive criteria as dictated by structural design or regulatory requirements shall govern.

GEO-17 Retaining Walls
 Foundations: Retaining wall foundations may be supported on either compacted engineered fill or competent bedrock. If a bedrock/fill transition is encountered, the bedrock portion shall be overexcavated minimum 2 feet and replaced with approved compacted fill. Alternatively, a cold joint shall be constructed in both the footing and the wall. Footings may be designed in accordance with the foundation design criteria presented in the Geotechnical Report when embedded at least two feet below lowest adjacent grade. Footings located on or at top of slopes shall be deepened, as necessary, to provide minimum lateral setback between footing and slope faces in accordance with CBC requirements.
 Lateral Earth Pressures: The earth pressures acting on retaining walls depend primarily on allowable wall movement, type of backfill materials, backfill slopes, wall inclination, surcharges, and any hydrostatic pressure. The following lateral earth pressures are recommended for vertical walls with no hydrostatic pressure and no surcharge loading:

Wall Condition Backfill Type Lateral Earth Pressure (Equivalent Fluid Pressure) (pcf)
Level 2:1 (H:V)
Active (Cantilever) Sandy Soils 40 65
The surcharge effect of anticipated loads on the wall backfill (i.e. traffic, construction equipment, footings, etc.) shall be included in the wall design. If the wall is free to deflect, 33 percent of the maximum surcharge load located within a distance equal to the height of wall shall be used in the design.
 Backfill: Retaining wall backfill shall consist of predominantly granular non-expansive soils.

The backfill shall extend within a 45-degree plane from the wall footing. Retaining wall backfill shall be mechanically compacted to minimum 90 percent of the applicable laboratory maximum density and performed under the observation and testing of the Project Geotechnical Engineer. No jetting, ponding, or flooding shall be permitted. No backfill shall be placed against concrete until minimum design strengths are attained.  Backfill Drainage: The wall design shall include waterproofing and weep holes or sub-drains or backdrains, as appropriate, for relieving possible hydrostatic pressures. If on-site soils are utilized for wall backfill, the design shall include a prefabricated drainage blanket (such as

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Miradrain 2000, or equivalent). At a minimum, sub-drains shall consist of 4-inch diameter, perforated Schedule 40, PVC pipe or equivalent, embedded in approximately 3 cubic feet per lineal foot of ¾-inch (maximum) rock, or approved alternate. This permeable material shall be enveloped in Geofabric consisting of Mirafi 140 or equivalent. The pipe and trench bottom shall be sloped at a gradient of 2+ percent to a suitable discharge outlet. Sub-drains placed behind retaining walls shall be approved by the Project Geotechnical Engineer prior to backfill placement.

GEO-18 Soil Corrosion. The previous geotechnical consultants, Pacific Soils Engineering, Inc., performed preliminary testing and indicated that the site soils are corrosive to metals. Therefore, representative finished grade samples shall be tested for corrosion suites (sulfate, chloride, pH and resistivity) upon completion of grading. It may be necessary to retain a corrosion engineer for consultation.

GEO-19 Utility Trench Backfill
 Bedding material shall consist of on-site sandy or imported materials exhibiting a San Equivalent (S.E.) value of 30 or greater.
 The on-site soils are considered suitable for trench backfill, provided they are free of organic materials and oversize rocks.
 Backfill of all exterior and interior trenches shall be placed in thin lifts not exceeding 4 inches and mechanically compacted to achieve a relative compaction of not less than 90% based on ASTM: D1157. Care shall be taken not to damage utility lines.  Utility trenches shall not be located within the influence of footings. This is defined as a zone located below the footing and a line sloping at an inclination of 1:1 (horizontal to vertical) outward from the outside edge of footings. If utility lines are located within the zone of footings, the backfill shall be compacted to a minimum 95 percent relative compaction or slurry backfilled (minimum 1-1/2 sack cemented sand mix.  To reduce potential water migration into building subgrade through the granular bedding/shading layer and/trench backfill, utility trenches shall be backfilled with the onsite finer grained materials or sand-cement slurry for minimum 3 feet length at their entry points.  Trenches in fill soils and alluvial deposits greater than 4 feet in depth shall be shored or sloped back as required by the local regulatory agency, the state of California Division of Industrial Safety Construction Safety Orders, and Federal OSHA requirements.

GEO-20 Asphalt Concrete Pavement. Preliminary asphalt concrete pavement sections for the planned streets in the development were developed utilizing the Caltrans method of design and the structural section design guide for California cities and counties. The following recommended pavement sections were computed assuming an “r” value of 30 for site soils compacted as subgrade material, and assumed traffic indices. The actual “r” value will depend on the soil conditions exposed at the planned street sub-grade elevations. During rough grading, “r” value testing shall be performed on the pavement sub-grade soils to confirm the pavement design basis. Further