Rialto City Council
July 25, 2023

City of Rialto Housing Element Update
Rezone Program
Initial Study/Mitigated Negative Declaration
Addendum
February 2023

Prepared By:

Kimley-Horn and Associates, Inc.
3880 Lemon Street, Suite 420
Riverside, CA 92501
Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

Page i February 2023
Table of Contents

1.0 Introduction and Purpose ................................................................................................................. 1

1.1 Purpose and Scope of the Addendum ................................................................................... 1

2.0 Description of Proposed Project ....................................................................................................... 3

2.1 Project Setting and Location .................................................................................................. 3 POPULATION ..................................................................................................................................... 3 HOUSING ........................................................................................................................................... 3 GENERAL PLAN .................................................................................................................................. 4 ZONING ............................................................................................................................................. 5

2.2 Project Description ................................................................................................................. 5

2.3 Project Approvals ................................................................................................................... 7

3.0 The Rialto HEU ISMND Environmental Impact Analysis Summary ................................................. 15

4.0 City of Rialto Housing Element Update Rezone Program Environmental Impact Analysis and Project Approvals ............................................................................................................................ 17 AESTHETICS ..................................................................................................................................... 18 AGRICULTURE AND FORESTRY RESOURCES .................................................................................... 21 AIR QUALITY .................................................................................................................................... 22 BIOLOGICAL RESOURCES ................................................................................................................ 24 CULTURAL RESOURCES ................................................................................................................... 26 ENERGY ........................................................................................................................................... 29 GEOLOGY AND SOILS ...................................................................................................................... 30 GREENHOUSE GAS EMISSIONS ....................................................................................................... 33 HAZARDS AND HAZARDOUS MATERIALS ........................................................................................ 34 HYDROLOGY AND WATER QUALITY ................................................................................................ 37 LAND USE AND PLANNING .............................................................................................................. 40 MINERAL RESOURCES ..................................................................................................................... 41 NOISE .............................................................................................................................................. 42 POPULATION AND HOUSING .......................................................................................................... 44 PUBLIC SERVICES ............................................................................................................................. 46 RECREATION.................................................................................................................................... 47 TRANSPORTATION .......................................................................................................................... 48 TRIBAL CULTURAL RESOURCES ....................................................................................................... 50 UTILITIES AND SERVICE SYSTEMS ................................................................................................... 52 Housing Element Update Rezone Program
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WILDFIRE ......................................................................................................................................... 55

5.0 Determination of Appropriate CEQA Documentation .................................................................... 56

6.0 Conclusion ....................................................................................................................................... 59

7.0 References ....................................................................................................................................... 60

Tables
Table 1-1: City of Rialto 2021-2029 RHNA Allocation ................................................................................... 2 Table 2-1: Candidate Housing Sites - Existing General Plan Land Use Designations .................................... 4 Table 2-2: Candidate Housing Sites - Existing Zoning ................................................................................... 5 Table 2-3: Approved Rialto HEU Assumed Density Rezone Estimates ......................................................... 6 Table 2-4: Proposed Planned Density Rezone Estimates .............................................................................. 6 Table 14-1: Population Estimate Comparison ............................................................................................ 44

Exhibits
Exhibit 2-1: Regional Vicinity Map ................................................................................................................ 8 Exhibit 2-2: Local Vicinity Map ...................................................................................................................... 9 Exhibit 2-3: Proposed Overlay for Opportunity Area 1 ............................................................................... 10 Exhibit 2-4: Proposed Overlay for Opportunity Area 2 ............................................................................... 11 Exhibit 2-5: Proposed Overlay for Opportunity Area 3 ............................................................................... 12 Exhibit 2-6: Proposed Overlay for Opportunity Area 4 ............................................................................... 13 Exhibit 2-7: Proposed Overlay for Opportunity Area 5 and 6 ..................................................................... 14

Appendices
Appendix A: Mitigation Monitoring and Reporting Program

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1.0 INTRODUCTION AND PURPOSE

1.1 Purpose and Scope of the Addendum
This Addendum has been prepared in accordance with the provisions of the California Environmental Quality Act (CEQA) (California Public Resources Code [PRC] Section 21000 et seq.); the CEQA Guidelines (Title 14, California Code of Regulations [CCR] Section 15000 et seq.); and the rules, regulations, and procedures for implementing CEQA as set forth by the City of Rialto (City). The City is the lead agency under the CEQA.

Section 15164(a) of the CEQA Guidelines states that “the lead agency or a responsible agency shall prepare an addendum to a previously certified EIR if some changes or additions are necessary, but none of the conditions described in Section 15162 calling for preparation of a subsequent EIR have occurred.” Section 15162(a) of the CEQA Guidelines indicates that the lead agency may forgoe the creation ofa subsequent EIR (SEIR) unless the lead agency determines, on the basis of substantial evidence in the light of the whole record, one or more of the following:
(1) Substantial changes are proposed in the project which will require major revisions of the previous EIR or negative declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects; (2) Substantial changes occur with respect to the circumstances under which the project is undertaken which will require major revisions of the previous EIR or Negative Declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects; or
(3) New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time the previous EIR was certified as complete or the Negative Declaration was adopted, shows any of the following:
(A) The project will have one or more significant effects not discussed in the previous EIR or negative declaration;
(B) Significant effects previously examined will be substantially more severe than shown in the previous EIR;
(C) Mitigation measures or alternatives previously found not to be feasible would in fact be feasible, and would substantially reduce one or more significant effects of the project, but the project proponents decline to adopt the mitigation measure or alternative; or (D) Mitigation measures or alternatives which are considerably different from those analyzed in the previous EIR would substantially reduce one or more significant effects on the environment, but the project proponents decline to adopt the mitigation measure or alternative.

The City of Rialto 6
th Cycle Housing Element (Rialto HEU) and its Approved Final Initial Study/ Mitigated Negative Declaration (Approved ISMND) was adopted by City Council in March 2022.1 The Rialto HEU was

1 City of Rialto. 2022. Plan to House Our Rialto: 2021-2029 Housing Element Update. Retrieved from: https://www.yourrialto.com/633/Plan- to-House-Our-Rialto-Housing-Element (Accessed November 30, 2022) Housing Element Update Rezone Program
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prepared as part of a new update cycle for jurisdictions within the Southern California Association of Governments ( SCAG) region to allow for synchronization with SCAG’s Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS). The Rialto HEU set forth an eight-year strategy (2021- 2029) to address the City’s identified housing needs, including specific impleme nting programs and activities.

The Rialto HEU was prepared as the sixth element of the Rialto General Plan (Rialto GP) and functions as one of seven State-mandated General Plan elements (i.e., Land Use, Housing, Circulation, Noise, Safety, Open Space, and Conservation) that are prepared according to CGC §65583 requirements. California Government Code §65583 sets forth the specific content requirements of a jurisdiction’s housing element.

Included in these requirements are obligations on the part of local ju risdictions to provide their “fair share” of regional housing needs.

The Rialto HEU also included policies and goals designed to assist the City in meeting its state -mandated Regional Housing Needs Assessment (RHNA) allocation. Like the creation of the Ria lto HEU, the City’s RHNA allocation is mandated by State Housing Law as part of the periodic process of updating local General Plan Housing Elements. It quantifies the housing need within each jurisdiction for all economic segments of the community (known as RHNA allocation plan) in four income categories: very low, low, moderate, and above moderate. Table 1-1: City of Rialto 2021-2029 RHNA Allocation provides the final RHNA allocation to the City as analyzed in the Approved ISMND.

Table 1-1: City of Rialto 2021-2029 RHNA Allocation
Income Level % of Average Median Income (AMI) RHNA Allocation (Housing Units)
Very Low Income <50% 2,218
Low-income 50-80% 1,206
Moderate Income 80-120% 1,371
Above Moderate Income >120% 3,477
Total 8,272
Source: Southern California Association of Governments (SCAG). 2021. Retrieved from: https://scag.ca.gov/sites/main/files/file- attachments/6th-cycle-rhna-proposed-final-allocation-plan.pdf?1614911196 (Accessed November 30, 2022) Housing Element Update Rezone Program
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2.0 DESCRIPTION OF PROPOSED PROJECT

2.1 Project Setting and Location
The City of Rialto (City) is in the southwest portion of the County of San Bernardino (County) in an area that is also referred to as the Western San Bernardino Valley. The City is bounded by unincorporated County areas to the northeast and southwest, Coun ty of Riverside to the south, the Cities of Colton and San Bernardino to the east, and the City of Fontana to the west. Regional access to the City is provided via Interstate 210 (I-210) and Interstate 10 (I-10), which traverse the City in an east -west orientation, in the northern and southern portions, respectively. Exhibit 2-1: Regional Vicinity Map depicts the City’s location in a regional context, while Exhibit 2-2: Local Vicinity Map depicts the City in a local context.

The City is predominantly comprised of residential land uses, with other notable land uses including major commercial uses along Foothill Boulevard (Historic Route 66), Riverside Avenue, Valley Boulevard, Renaissance Parkway, and Baseline Road at Riverside Avenue, as well as industrial and warehouse uses along Rialto’s rail lines, and north of I-210 and south of I-10.

The City’s topography is relatively flat with an elevation of approximately 1,257 feet above mean sea level (amsl).
2 The Lytle Creek Wash and Cajon Wash lie north of the City.

POPULATION
In 2010, the California Department of Finance (DOF) estimated Rialto’s population to be 99,171 persons.3 In 2020, SCAG’s 2016 -2040 Regional Transportation Plan and Sustainable Communities (RTP/SCS) estimated Rialto’s population to be 104,110 persons.4 From 2010 to 2020, the City’s population increased by approximately 5 percent (4,929 persons). The City’s population is forecasted to grow to approximately 112,000 persons through 2040.5 Therefore, Rialto is projected to grow approximately 7.6 percent (7,900 persons) between 2020 and 2040.

HOUSING
In 2010, the California Department of Finance (DOF) estimated Rialto’s number of households to be 25,185.6 SCAG’s 2016-2040 RTP/SCS estimated Rialto’s number of households to be 25,400 in 2012 and 28,000 in 2020. 7 From 2012 to 2020, the City’s total number of households increased by approximately

10.2 percent (2,600 households). The City’s number of households is forecasted to grow to approximately 31,500 through 2040.8 Therefore, Rialto’s number of households is projected to grow approximately 24 percent (6,100 households) between 2020 and 2040. According to the California DOF, the City’s housing stock totaled approximately 27,619 housing units as of January 2021, with single -family homes

2 U.S. Geological Survey (USGS).2022. Domestic Names. Available at https://geonames.usgs.gov/apex/f?p=gnispq:3:::NO::P3_FID:1661306.

Accessed on August 18, 2021.
3 United States Census Bureau. Quick Facts Rialto City, California. Retrieved from https://www.census.gov/quickfacts/rialtocitycalifornia (Accessed November 30, 2022).
4 Southern California Association of Governments (SCAG). 2016-2040 RTP/SCS Final Growth Forecast by Jurisdiction. Retrieved from:
https://scag.ca.gov/sites/main/files/file-attachments/2016_2040rtpscs_finalgrowthforecastbyjurisdiction.pdf?1605576071 (Accessed on November 30, 2022)
5 Ibid.
6 United States Census Bureau. Quick Facts Rialto City, California. Retrieved from https://www.census.gov/quickfacts/rialtocitycalifornia Accessed on August 18, 2021.
7 Southern California Association of Governments (SCAG). Retrieved from 2016-2040 RTP/SCS Final Growth Forecast by Jurisdiction. Accessed on August 18, 2021.
8 Ibid.

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(detached and attached) as the predominant housing type in the City. 9 Single-family housing units make up approximately 74 percent (or 20,455 units) of the City’s housing stock and multi-family units make up approximately 20 percent (or 5,418 units) of the housing stock.10 Mobile homes make up approximately

6.3 percent (or 1,746 units) of the City’s total housing stock.11

GENERAL PLAN
The Rialto GP was adopted in December 2010. It provides the City’s long-range planning goals and policies for development within the City. The Rialto GP is the City’s vision for growth to 2040. Rialto GP Chapters two through seven include the necessary GP elements: Land Use, Open Space, Community Design, Conservation, Economic Development, Redevelopment, Infrastructure, Public Services and Facilities, Circulation, Safety and Noise, Housing, and Cultural and Historic Resources.

The Land Use Element describes the City’s existing land use characteristics and development patterns and establishes a plan for future development and redevelopment. The existing GP land use designations associated with the Project are described in Table 2-1: Candidate Housing Sites - Existing General Plan Land Use Designations.

Table 2-1: Candidate Housing Sites - Existing General Plan Land Use Designations Land Use Designation Description
R6 - Residential 6
(Density: 2.1-6 du/ac)
Allows for the development of single -family detached residences with a density of 2.1 to 6 dwelling units per acre.

R21 - Residential 21
(Density: 12.1-21 du/ac)
Allows for the development of low-scale attached units with private and/or shared open space, and groups of attached housing with larger common open space areas with a density of 12.1 to 21 dwelling units per acre.

O – Office
(Intensity: maximum 0.75 FAR)
Allows for small - and large -scale professional offices and related uses to accommodate a broad range of low -intensity, service -oriented, and employment-generating uses.

DMU - Downtown Mixed Use
(Intensity: 6.1- 60 du/ac; maximum

1.50 FAR)
Allows for the development of single -family attached or detached residences with a density of 22.1 to 30 dwelling units per acre.

CC – Community Commercial
(Intensity: maximum 0.35 FAR)
Allows for a variety of retail, office, and service-oriented business activities that serve the local community, including supermarkets, restaurants, small- scale service businesses, and specialty retail stores
GC – General Commercial
(Intensity: maximum 0.50 FAR)
Allows for opportunities for general retail, commercial services, restaurants, lodging, commercial recreation, prof essional offices, and medical and financial institutions.

BP – Business Park
(Intensity: maximum 1.0 FAR)
Allows a mix of commercial, office, research and development, laboratories, and light industrial uses developed in a complementary manner and displaying high-quality architecture and site design SP – Specific Plan Specific plans create and specify the land use designations for the areas that they contain. However, the land use designations must be consistent with the General Plan.

Source: City of Rialto. (2010). City of Rialto General Plan. Pages 2-4 through 2-9. Retrieved from:
https://yourrialto.com/DocumentCenter/View/1494/2010-General-Plan. (Accessed November 30, 2022).

9 Ibid.
10 Ibid.
11 Ibid.

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ZONING
The City’s Zoning Code can be found in City of Rialto Municipal Code (Rialto MC) Title 18. The Zoning Code’s intent is to establish permitted land uses and development standards for each zone. It also is intended to implement GP goals and objectives; guide and manage development within the City in accordance with the GP; as well as reduce hazards to the public resulting from the inappropriate location, use, or design of buildings and other improvements. The existing zoning associated with the Project are described in Table 2-2: Existing Zoning.

Table 2-2: Candidate Housing Sites - Existing Zoning
Zone Description
Single Family Residential (R-1A) Allows for the development of a single one-family dwelling on a minimum 10,000 square foot lot.

Single Family Residential (R-1B) Allows for the development of a single one-family dwelling on a minimum 8,400 square foot lot.

Single Family Residential (R-1C) Allows for the development of a single one-family dwelling on a minimum 7,700 square foot lot.

Multi-Family Residential (R-3)
Allows for the development of multiple family attached dwellings of up to four units. Five or more units can be conditionally allowed. Lots must be a minimum of one acre.

Administrative-Professional (A-P) Allows for the development of offices for the practice of a prof ession, administration of a business.

Neighborhood Commercial (C-1) Allows for the development of retail stores, offices (business or professional), and certain services.

Community Shopping Center (C-1A) Allows for the development of uses permitted in C-1 and additional uses.

Foothill Boulevard Specific Plan
Allows for development of high density residential, residential uses mixed with less-intense commercial uses, and muti-story development to encourage revitalization of existing development.

Lytle Creek Ranch Specific Plan Allows for the development of residential uses with density of 5-14 du/ac and for open space, neighborhood parks, golf, and recreation areas.

Renaissance Specific Plan Allows for the development or residential uses with density of 3-35 du/ac.

Gateway Specific Plan Allows for the development of retail commercial, office park, and industrial park uses.

Central Area Specific Plan
Allows for the development of commercial manufacturing or light industrial land uses, commercial uses, and increased density residential uses.

Rialto Airport Specific Plan Allows for a range of uses including commercial, office, industrial, and residential uses.

Source: City of Rialto. (2010). City of Rialto Municipal Code Title 18. Available at https://library.municode.com/ca/rialto/codes/code_of_ordinances?nodeId=TIT18ZO. Accessed September 7, 2021.

2.2 Project Description
The Approved ISMND considered 312 candidate housing sites within the City’s boundaries, as identified in the Plan to House Our Rialto: 2021-2029 Housing Element Update. See Appendix A: Candidate Housing Sites Inventory of the Approved ISMND.
12 Additionally, the Approved ISMND assessed future housing

12 City of Rialto. 2021. City of Rialto 6th Cycle Housing Element Update (2021-2029) Initial Study/Mitigated Negative Declaration. Retrieved from: https://www.yourrialto.com/DocumentCenter/View/2120/ISMND_Rialto-Housing-Element-Update (Accessed November 30, 2022) Housing Element Update Rezone Program
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development based on the assumed density of the identified housing sites based on their realistic ability to be used for housing development.13
Assumed density refers to the realistic buildout potential of an area based on previous development patterns and existing development. Planned density refers to the allowed buildin g potential of an area, not including or accounting for realistic building potential or existing structures. Table 2 -3, Approved Rialto HEU Assumed Density Rezone Estimates summarizes the projected future development based on the assumed densities of each candidate housing rezone areas.

Table 2-3: Approved Rialto HEU Assumed Density Rezone Estimates Very Low
Income
Low
Income
Moderate
Income
Above Moderate
Income Total
RHNA Allocation (2021-2029) 2,218 1,206 1,371 3,477 8,272 Approved MND Rezone Estimates
1 - Foothill Boulevard Specific Plan 1,603 153 1,210 2,966 2 - North Riverside Avenue 219 19 159 397
3 - Gateway Specific Plan 384 35 278 697
4 – Rialto Central Area Specific Plan 240 11 191 442
5 - Baseline Parcels 80 5 61 146
6 - Baseline Shopping Center 464 43 329 836

Total Capacity Under
Rezone/Upzone 3,055 271 2,274 5,600
Total Potential Development
Capacity (Constructed/Permit
Issued, Existing Zoning and
Rezone/Upzone)
4,619 1,427 10,206 16,368

The City of Rialto Housing Element Rezone Program Project (Project) proposes Specific Plan Amendments (SPAs) over Opportunity Areas 1, 3, and 4. A Zoning Code Amendment (ZCA) is also proposed to create a 50 dwelling unit per acre (du/ac) residential overlay on Opportunity Areas 2, 5 and 6. These changes would modify the planned density of each rezone focus area and increase their allowed build potential. These changes would not alter the assumed density which was established in the Rialto HEU and analyzed in the Approved ISMND. Table 2-4: Proposed Planned Density Rezone Estimates summarizes maximum allowed residential development in each focus area that would be facilitated by the rezones. Each proposed overlay is included in Exhibit 2-3 through Exhibit 2-7.

Table 2-4: Proposed Planned Density Rezone Estimates

Very Low
Income
Low
Income
Moderate
Income
Above
Moderate
Income
Total
RHNA Allocation (2021-2029) 2,218 1,206 1,371 3,477 8,272 Proposed Rezone Estimates
1 - Foothill Boulevard Specific Plan 1,619 152 1230 3001

13 See page B-35 of Appendix B of the Rialto 6th Cycle Housing Element Update Housing Element Update Rezone Program
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Very Low
Income
Low
Income
Moderate
Income
Above
Moderate
Income
Total
2 - North Riverside Avenue 467 43 339 848
3 - Gateway Specific Plan 548 50 399 997
4 – Rialto Central Area Specific Plan 370 35 267 672
5 - Baseline Parcels 215 19 157 391
6 - Baseline Shopping Center 1,565 142 1,138 2,845
Total Capacity Under
Rezone/Upzone 4,784 441 3,530 8,754
Change from Approved Project +1,729 +170 +1,256 +3,154
*Note 1 – unit capacity shown is the planned density units gained by the rezone.

2.3 Project Approvals
The City is the Lead Agency as set forth in CEQA Statute Section 21067 and is responsible for reviewing and approving this Addendum to Approved ISMND. In addition to th is Addendum, the City will consider the following discretionary approvals for the Project:
• Specific Plan Amendment – Increase maximum density for 159 acres within the Foothill Boulevard Specific Plan.
• Specific Plan Amendment – Increase maximum density for fourteen (14) acres within the Rialto Central Area Specific Plan
• Specific Plan Amendment – Incresae maximum density for twenty (20) acres within the Gateway Specific Plan.

Zoning Code Amendment – Create a residential overlay which would allow for a maximum residential development density of 50 du/ac in Opportunity Areas 2, 5, and 6.

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Exhibit 2-1: Regional Vicinity Map

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Exhibit 2-2: Local Vicinity Map

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Exhibit 2-3: Proposed Overlay for Opportunity Area 1

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Exhibit 2-4: Proposed Overlay for Opportunity Area 2

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Exhibit 2-5: Proposed Overlay for Opportunity Area 3

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Exhibit 2-6: Proposed Overlay for Opportunity Area 4

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Exhibit 2-7: Proposed Overlay for Opportunity Area 5 and 6

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3.0 THE RIALTO HEU ISMND ENVIRONMENTAL IMPACT ANALYSIS

SUMMARY
The environmental impact findings of the Approved ISMND are summarized below.

No Impact: The Approved ISMND determined that no impact would occur with respect to the following environmental topic areas below:
• Aesthetics Impact 1(b);
• Agriculture and Forestry Impact 2(a-e);
• Biological Resources Impacts 4(c-d);
• Geology and Soils Impact 7(e);
• Hazards and Hazardous Materials Impacts 9(d-e);
• Mineral Resources Impact 12(a-b);
• Noise Impact 13(c);
Less Than Significant Impact: The Approved ISMND identified less than significant impacts in the following environmental topic areas:
• Aesthetics Impacts 1(a, c-d));
• Air Quality Impact 3(a-d);
• Biological Resources Impacts 4(e-f);
• Energy Impact 6(a-b);
• Geology and Soils Impacts 7(a-d, f);
• Greenhouse Gas Impact 8(a-b);
• Hazards and Hazardous Materials Impacts 9(a, c, f-g); • Hydrology and Water Quality Impacts 10(a-e);
• Land Use and Planning Impacts 11(a-b);
• Noise Impacts 13(a-b)
• Population and Housing Impacts 14(a-b);
• Public Services Impacts 15(a-e);
• Recreation Impacts 16(a-b);
• Transportation Impacts 17(a-d); and
• Utilities and Service Systems Impacts 19(a-e).
• Wildfire Impacts 20(a-d)
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Less Than Significant Impact with Incorporation of Mitigation: The Approved ISMND identified impacts that could be mitigated to less than significant levels with incorporation of mitigation measures in the following environmental topic areas:
• Biological Resources Impacts 4(a-b);
• Cultural Resources Impact 5(a-c);
• Hazards and Hazardous Materials Impact 9(b)
• Tribal Cultural Resources Impact 18(a-b)
Significant and Unavoidable Impact: The Approved ISMND identified no significant and unavoidable impacts.

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City of Rialto Initial Study/Mitigated Negative Declaration Addendum

4.0 CITY OF RIALTO HOUSING ELEMENT UPDATE REZONE PROGRAM

ENVIRONMENTAL IMPACT ANALYSIS AND PROJECT APPROVALS
The scope of the City’s review of the Project is set forth in CEQA and the CEQA Guidelines. This review is limited to evaluating the environmental effects associated with the Project when compared to the Rialto HEU as set forth in the Approved ISMND. This Addendum also reviews new information, if any, of substantial importance that was not known and could not have been known with the exercise of reasonable due diligence at the time the Approved ISMND was certified. This evaluation includes a determination as to whether the changes proposed for the Project would result in any new significant impacts or more severe significant impact.

Although CEQA Guidelines Section 15164 does not stipulate the format or content of an Addendum, the topical areas identified in the Approved ISMND were used as guidance for this Addendum. In addition, Section 15164(e) of the CEQA Guidelines states that “A brief explanation of the decision not to prepare a subsequent [ISMND] pursuant to Section 15162 should be included in an addend um to an [ISMND] , the lead agency's findings on the Project, or elsewhere in the record. The explanation must be supported by substantial evidence.” This comparative analysis provides the City with the factual basis for determining whether any changes in t he Project, any changes in circumstances, or any new information since the Approved ISMND was certified would require additional environmental review or preparation of a new ISMND.

Pursuant to CEQA Guidelines Section 15162, the City has determined, on the basis of substantial evidence in the light of the whole record, that implementation of the Project does not propose substantial changes to the Approved ISMND, no substantial changes in circumstances would occur which would require major revisions to the Approved ISMND, and no new information of substantial importance has been revealed since the certification of the Approved ISMND that would result in either new significant effects or an increase in the severity of previously analyzed significant effects.

A Mitigation Monitoring and Reporting Program (MMRP) was adopted as a part of the Approved ISMND that minimized impacts associated with implementation of the Approved ISMND. The previously adopted Approved ISMND mitigation measures applicable to the Project would be collectively imposed as the Project’s MMRP, which is contained in Appendix A.

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Initial Study/Mitigated Negative Declaration

AESTHETICS
Summary of Previous Environmental Analysis
The Approved ISMND concluded that due to the Rialto HEU’s lack of physical components and lack of directly proposed physical development, no significant impacts were anticipated to aesthetic resources.

Future housing development assessed in the Approved IS MND would be required to comply with any relevant local, state, and federal regulations regarding visual resources. Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
1(a) Have a substantial adverse effect on a scenic vista? No New or More Significant Impact s: The Approved ISMND cited the San Gabriel Mountains and San Bernardino Mountains located to the north of the City and the La Loma Hills, Jurupa Hills, Box Spring Mountains, Moreno Valley, and Riverside located to the south of the City as the main scenic vistas visible from the City.
14 Like the Rialto HEU, the Project would not have a substantial adverse effect on scenic vistas because the Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City.

All future housing development would be required to comply with established state and local requirements. Accordingly, no new impacts relative to adverse effects on a scenic vista or a substantial increase in the severity of a previously identified significant impact evaluated in the Approved ISMND would occur. The Project would not have a more severe or substantial adverse effect on a scenic vista than what was originally analyzed in the Approved ISMND.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
1(b) Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a State scenic highway? No New or More Significant Impact s: The Project site is not within or adjacent to a scenic highway. No eligible or officially designated highways exist within the City. Therefore, no new or more severe impacts would occur in this regard. No new and/or modified mitigation measures are required for issue s related to aesthetics.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

14 City of Rialto. (2010). The City of Rialto General Plan. Retrieved from: https://yourrialto.com/DocumentCenter/View/1494/2010-General- Plan. (Accessed December 1, 2022).

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1(c) In non-urbanized areas, substantially degrade the existing visual character or quality of public views of the site and its surroundings? (Public views are those that are experienced from publicly accessible vantage points). If the project is in an urbanize d area, would the project conflict with applicable zoning and other regulations governing scenic quality?
No New or More Significant Impact. The Project would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City , which are situated in urbanized areas. Therefore, the Project would result in a significant impact if it would conflict with applicable zoning and other regulations governing scenic quality.

The Rialto GP contains goals and policies that govern scenic quality. Goal 2-14 includes policies which are intended to protect the scenic vistas and resources within the City. Table 2-4 lists the zoning for each of the candidate housing sites, as well as their corresponding regulations. The regulations specified in Table 2-4 do not include standards governing scenic quality. Rialto MC §18.61 – Design Guidelines does contain standards that protect scenic quality by preserving the existing character of established residential neighborhoods, and protecting public and private views, and aesthetic resources.

All future housing development facilitated by the HEU would be subject to the City’s development review process, which may include review pursuant to CEQA, and be required to comply with GP policies, Rialto MC standards, as well as all applicable requirements concerning those that protect against degradation of visual resources by requiring project modifications, conditions of approval or mitigation measures, as needed. Because future housing development consistency with General Plan policies and compliance with Rialto MC standards would be verified through the City’s development review process, the project would not conflict with applicable policies or standards governing scenic quality. Therefore, impacts would be less than significant in this regard.

Additional future housing development would have potential to change the appearance of the City.

However, the Project would comply with applicable zoning and other regulations governing scenic quality such as Rialto GP goals and policies, Rialto MC design Guidelines, and all applicable requirements concerning degradation of visual resources. Compliance with the above policies and guidelines would ensure that future development facilitated by the Project would be developed consistently with the visual character of the area. Therefore, no new or more sever impacts are anticipated and/or modified mitigation measures are required for issues related to aesthetics.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
1(d) Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area?
No New or More Significant Impacts: As stated in the Approved ISMND, impacts regarding light and glare would remain less than significant as long as future development complies with GP policies, Title 24 of the California Green Building Standards Code, and applicable MC standards. The Project would remain consistent with the Approved ISMND in this regard.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

Consistency with these policies and regulations would ensure that potential impacts associated with light and glare would be less than significant. Consistent with the Approved ISMND , no mitigation measures are required. Accordingly, no new or more severe impacts relative to adverse impacts would occur.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND along with a no impact determination. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to aesthetics.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

AGRICULTURE AND FORESTRY RESOURCES
Summary of Previous Environmental Analysis
The Approved ISMND concluded that due to the City’s lack of agriculturally developed land within the Rialto HEU area no impact would occur.

Analysis of Proposed Project
2(a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? 2(b) Conflict with existing zoning for agricultural use, or a Williamson Act contract? 2(c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code section 12220(g)), timberland (as defined by Public Resources Code section 4526), or timberland zoned Timberland Production (as defined by Government Code section 51104(g))?
2(d) Would the project result in the loss of forest land or conversion of forest land to non- forest use?
2(e) Would the project involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland, to non -agricultural use or conversion of forest land to non-forest land?
No New or More Significant Impact s: Future housing development facilitated by the Project would not be constructed within portions of the City designated for agricultural land uses. Furthermore, future housing development would occur on parcels zoned for residential uses. Future development would also not occur on lands designated as Prime Farmland, Unique Farmland, Farmland of Statewide Importance, or Williamson contract agriculture. Furthermore, the developed state of the Project would not cause its redevelopment to affect surrounding farms as future housing development would not be located within agricultural or forestry uses. As such, no new or more severe impacts related to the loss of farmland would occur and no new and/or modified mitigation measures are necessary.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. No impact was identified in the Approved ISMND. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to agriculture and forestry.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

AIR QUALITY
Summary of Previous Environmental Analysis
The Approved ISMND concluded that a less than significant impact would occur due to future developments associated with the Rialto HEU’s requirement to comply with State Air Quality regulations.

Future housing development assessed in the Approved ISMND would be required to comply with any relevant local and federal regulations regarding air quality . Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
3(a) Conflict with or obstruct implementation of the applicable air quality plan? 3(b) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non- attainment under an applicable federal or state ambient air quality standard?
No N ew or More Significant Impact . Similar to the Rialto HEU, the Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development.

It is assumed that future housing on these sites would be developed with greater planned density than assumed in the GP and SCAG’s growth projections. However, the Project would remain consistent with the assumed density analyzed in the Approved ISMND. As well, future housing development facilitated by the HEU would be subject to the City’s development review process, which may include review pursuant to CEQA, and be required to comply with GP policies, Rialto MC standards, as well as required to adhere to all federal, state, and local regulations for minimizing construction and operational pollutant emissions, including South Coast Air Quality Management District (SCAQMD) Rules 402 (Nuisance), 403 (Fugitive Dust), and 1113 (Architectur al Coatings). Therefore, no new or more severe impacts are expected.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
3(c) Expose sensitive receptors to substantial pollutant concentrations? No New or More Significant Impact. The Project would not impede future developments from compliance with various regulations including California Code of Regulations (CCR) 2449 and 13 CCR 2485) and requirements involving improvements in vehicular emissions. Changes proposed by the Project would not result in an increase in Diesel Particulate Matter(DPM) or potential for Carbon Monoxide (CO) hotspots in the South Coast Air Basin (SoCAB). Additionally, the future development of housing sites facilitated by the Project would not increase with changes to the Project and therefore, it would remain unlikely that future housing development facilitated by the Project would require the extensive operation of heavy -duty construction equipment, or extensive use of diesel trucks. Future housing development would still require further evaluation of the potential for the formation of microscale CO “hotspots” through the City’s development review process to demonstrate that both daily construction emissions and operations would not exceed SCAQMD ’s significance thresholds for any criteria air pollutant. Lastly, future construction Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

activities would be subject to environmental review under CEQA and compliance with SCAQMD Rules .

Therefore, no new or more severe impact would occur and no new and/or modified mitigation measures would be required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
3(d) Result in other emissions (such as those leading to odors) adversely affecting a substantial number of people?
No New or More Significant Impact. Future housing development facilitated by the Project would not be constructed within portions of the City designated for agriculture, wastewater treatment plants, food processing plants, chemical plants, compos ting facilities, refineries, landfills, dairies, and fiberglass molding land uses. Therefore, the Project would not include any of the land uses that have been identified by the SCAQMD as odor sources. However, vehicles and/or equipment exhaust during futu re development construction could result in odors. These odors would only exist temporarily and would disperse rapidly. The Projects is also not expected to have large portions of DPM emissions (refer to Impact 3(c) above). Therefore, no new or more severe impact would occur.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. The Approved ISMND determined that less than significant impacts were identified. The Project would be consistent with the analysis contained in the Approved ISMND . Therefore, no new and/or modified mitigation measures are required for issues related to air quality.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

BIOLOGICAL RESOURCES
Summary of Previous Environmental Analysis
The Approved ISMND concluded that while the Rialto HEU would have no direct physical effects on the environment, mitigation was necessary to ensure that necessary precautions were taken in the future; including the completion of burrowing owl investigation s. Impacts were determined to be less than significant with the implementation of mitigation.

Analysis of Proposed Project
4(a) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special -status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
No New or More Significant Impact: The Project does not directly propose the development of housing units within the City. However, the Project does include updates to housing regulations within locations which are predominantly developed, disturbed, and/or adjacent to development due to majority of the City being urban and developed.

The Project would not result in a new or more severe impact on natural habitats and sensitive species. No sites associated with the Project are within the Lytle Creek Ranch Specific Plan (LCRSP) and therefore do not require enhanced biological mitigation. Therefore, no new or more severe impacts are anticipated without mitigation implemented.

Mitigation Program
Mitigation Measures from the Approved ISMND
None are applicable to the Project.
4(b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service? No New or More Significant Impact. As mentioned in impact 4(a), the Project does not include sites which are within the LCRSP. Therefore, enhanced biological analysis is not required.

However, all future housing development facilitated by the Project would be requir ed to demonstrate compliance with federal, state, and local requirements aimed at protecting biological resources, including those in the Rialto GP. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None applicable to the Project.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

4(c) Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
No New or More Significant Impact. Please see impact 4(a), the Project does not include sites which are within the LCRSP. Therefore, no new or enhanced biological assessment is required. Furthermore, no new or more significant impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
4(d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
No Impact. The Project footprints are in largely urbanized areas with limited natural activity. Additionally, please see impact 4(a), the Project does not include sites which are within the LCRSP. Therefore, enhanced biological analysis is not required. No new or more significant impact is anticipated. 4(e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
4(f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?
Less Than Significant Impact . As determined in the Approved ISMND the City does not have a tree preservation policy or ordinance and the City is not located within a Habitat Conservation Plan (HCP) or a Natural Community Conservation Plan (NCCP). 15 No new or more significant impact would occur in th is regard.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. The Approved ISMND determined that less than significant impacts were identified in the Approved ISMND. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to biological resources.

15 California Department of Fish and Wildlife. California Natural Community Conservation Plans. Available at https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=68626&inline. Accessed on August 24, 2021.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

CULTURAL RESOURCES
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the City’s cultural resources were located within the proximity of the Rialto HEU candidate sites. Because of this, mitigation was prepared to reduce the potential impacts associated with future development in those areas.

Analysis of Proposed Project
5(a) Cause an adverse change in the significance of a historical or archaeological resource pursuant to §15064.5?
5(b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to §15064.5?
No New or More Significant Impact s: As previously mentioned, the Project does not result in direct housing construction and all future housi ng development facilitated by the Project would be subject to the City’s development review process and regulatory framework. The Rialto GP identifies historical and cultural resources within the City . Similar to the Rialto HEU , the Project could potentially cause adverse change in the significance of a historical resource, however the Project would implement Mitigation Measure (MM) CUL-1 through MM CUL-5 of the Approved ISMND as well as San Manuel Band of Mission Indians (SMBMI) mitigations MM SMBMI-1 and MM SMBMI-2 along with the City’s GP goals and policies which preserve the City’s significant historical resources. Therefore, no new or more significant impacts would occur.

Mitigation Program
Mitigation Measures from the Approved ISMND
The Project would implement MM CUL-1 through MM CUL-5, and MM SMBMI-1 through MM SMBMI-2 of the Approved ISMND.

MM CUL-1 Archaeological Resources: For development projects or land use plans in areas determined to have a high potential for archaeological resources as determined through field surveys required by General Plan Policy 7-3.1, grading shall be monitored by trained archeological crews working under the direction of a qualified professional, so that resources exposed during grading can be recovered and the scientifically important information preserved. Archaeological monitors shall be equipped to recover resources as they are unearthed and to avoid construction delays. Monitors shall be empowered to temporarily halt or divert equipment to allow remo val of abundant or large specimens.

Qualified archaeological personnel shall prepare recovered specimens to a point of identification and permanent preservation. Qualified archaeological personnel shall identify and curate specimens into the collections of an appropriate, established, and accredited museum repository with permanent retrievable archaeological storage as determined in consultation with the Community Development Director. Qualified archaeological personnel shall prepare a report of findings with an appendix itemized of specimens subsequent to implementation of curation. A preliminary report shall be submitted to and approved by the Community Development Director before granting of Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

building permits and a final report shall be submitted to and approved by the Community Development Director before granting of occupancy permits MM CUL-2 Paleontological Field Surveys: In areas containing middle to late Pleistocene era sediments (Qof) where it is unknown if paleontological resources exist, field surve ys prepared by a qualified paleontological professional before grading shall be conducted to establish the need for paleontologic monitoring. Should paleontological monitoring be required after recommendation by the professional paleontologist and approval by the Community Development Director, Mitigation Measure C-3 shall be implemented.

MM CUL-3 Paleontological Monitoring: A project that requires grading plans and is located in an area of known fossil occurrence or that has been demonstrated to have fossi ls present in a field survey as described in MM CUL -2 shall have all grading monitored by trained paleontologic crews working under the direction of a qualified professional, so that fossils exposed during grading can be recovered and preserved. Paleontologic monitors shall be equipped to salvage fossils as they are unearthed, to avoid construction delays, and to remove samples of sediments that are likely to contain the remains of small fossil invertebrates and vertebrates. Monitors shall be empowered to temporarily halt or divert equipment to allow removal of abundant or large specimens. Monitoring is not necessary if the potentially fossiliferous units described for the property in question are not present or if present are determined upon exposure and ex amination by qualified paleontologic personnel to have low potential to contain fossil resources. Should paleontological resources require recovery, MM CUL-4 shall be implemented.

MM CUL-4 Paleontological Recovery, Identification, and Curation: Qualified paleontologic personnel shall prepare recovered specimens to a point of identification and permanent preservation, including washing of sediments to recover small invertebrates and vertebrates. Qualified paleontologic personnel shall identify and curate spe cimens into the collections of the Division of Geological Sciences, San Bernardino County Museum, an established, accredited museum repository with permanent retrievable paleontologic storage. The paleontologist must have a written repository agreement in hand prior to the initiation of mitigation activities. This measure is not considered complete until curation into an established museum repository has been fully completed and documented.

MM CUL-5 Paleontological Findings: Qualified paleontologic personne l shall prepare a report of findings with an appendix itemized of specimens subsequent to implementation of MM CUL-4. A preliminary report shall be submitted to and approved by the Community Development Director before granting of building permits and a final report shall be submitted to and approved by the Community Development Director before granting of occupancy permits.

MM SMBMI-1 In the event that cultural resources are discovered during future housing development facilitated by the HEU activities, all work in the immediate vicinity of the find (within a 60- foot buffer) shall cease and a qualified archaeologist meeting Secretary of Interior standards shall be hired to assess the find. Work on the other portions of the project outside of t he buffered area may continue during this assessment period. Additionally, the SMBMI Cultural Resources Department shall be contacted, as detailed within MM Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

TCR-1, regarding any pre-contact and/or post-contact finds and be provided information after the archaeologist makes his/her initial assessment of the nature of the find, so as to provide Tribal input with regards to significance and treatment.

MM SMBMI-2 During future housing development facilitated by the HEU activities, if significant pre - contact and/or post-contact cultural resources, as defined by CEQA (as amended, 2015), are discovered and avoidance cannot be ensured, the archaeologist shall develop a Monitoring and Treatment Plan, the drafts of which shall be provided to SMBMI for review and comment, as detailed within MM TCR-1. The archaeologist shall monitor the remainder of the project and implement the Plan accordingly. 5(c) Disturb any human remains, including those interred outside of dedicated cemeteries? No New or More Significant Impact s: As previously mentioned, the Project does not result in direct housing construction and all future housing development facilitated by the Project would be subject to the City’s development review process and regulatory framework. As addressed above, the Project would comply with the established regulatory framework and implement MM SMBMI -3 concerning the potential to disturb human remains interred outside of dedicated cemeteries. No new or more severe impacts would occur as a result of the Project and no new mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
The Project would implement MM SMBMI-3 of the Approved ISMND.

MM SMBMI-3 If human remains or funerary objects are encountered during any activities associated with future housing development facilitated by the HEU activities, work in the immediate vicinity (within a 100-foot buffer of the find) shall cease and the County Coroner shall be contacted pursuant to State Health and Safety Code §7050.5 and that code enforced for the duration of the project.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND with the implementation of mitigation. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to cultural resources.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

ENERGY
Summary of Previous Environmental Analysis
The Approved ISMND concluded that due to the Rialto HEU’s lack of physical characteristics and lack of directly proposed physical development. Future housing development assessed in the Approved ISMND would be required to comply with any relevant local, state, and federal regulations regarding energy usage. Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
6(a) Result in potentially significant environmental impact due to wasteful, inefficient, or unnecessary cons umption of energy resources, during Project construction or operation?
6(b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency? No New or More Severe Impact. The increased future housing development facilitated by this Project would involve increased construction activities and energy usage in the future. However, future development would be required to undergo environmental review according to State CEQA Guidelines and local standards. Additionally, each new dwelling unit would be required to utilize energy efficient building materials in its construction, including solar panels on each new single family dwelling unit.

As previously stated in the Approved ISMND, this Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City . Similarly, the Project does not directly result in increased energy usage and would neither facilitate wasteful or inefficient energy usage nor conflict with established energy regulation. Therefore, there are no new or more severe impacts.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to energy.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

GEOLOGY AND SOILS
Summary of Previous Environmental Analysis
The Approved ISMND concluded that while the Rialto HEU would have no direct physical effects on the environment, the potential for future development may exacerbate soil conditions in a harmful way.

However, these risks were ultimately determined to be less than significant. The seismicity of the Lytle Creek Specific Plan (LCRSP) was also assessed to be less than significant despite its proximity to an active fault line.

Analysis of Proposed Project
7(a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury or death involving:
i) Rupture of a known earthquake fault, as delineated on the most recent Alquist - Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault?
ii) Strong seismic ground shaking?
iii) Seismic-related ground failure, including liquefaction? No New or More Significant Impacts. The Alquist-Priolo Zones Special Studies Act defines active faults as those that have experienced surface displacement or movement during the last 11,000 years and prohibit the development of structures which allow for human occup ancy within their boundaries or along their fault lines. A portion of the San Jacinto Fault located in the City is considered an Alquist-Priolo Fault Zone.

This area is near LCRSP. 16The Project does not include parcels located in the proximity of this fault . No new or more severe impacts would occur, and no new mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
iv) Landslides?
No New or More Significant Impacts. As noted in the Approved ISMND, the Project area is relatively flat and within urbanized areas with low risk of landslides. Further, the Project does not include parcels in proximity of LCRSP . Therefore, the Project would result in no new or more severe impac ts regarding landslides and no new and/or modified mitigation measures are required for issues related to geological hazards.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

16 City of Rialto. Rialto General Plan 2010. Available at https://www.yourrialto.com/DocumentCenter/View/1494/2010-General-Plan. Accessed on September 2, 2021.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

7(b) Result in substantial soil erosion or the loss of topsoil? No New or More Significant Impact : As previously mentioned, the Project would not result in direct housing construction, but would facilitate and provide a policy framework for future housing development. Additionally, all future housing development would be subject to the City’s development review process and comply with Rialto GP policies and Rialto MC standards, and adhere to all federal, State and local requirements for avoiding and minimizing impacts concerning soil erosion or loss of topsoil.

The Project would be designed consistent wi th the applicable guidelines and standards within the Rialto GP, Rialto MC, and the California Building Code ( CBC). Therefore, the Project would result in no new or more severe impacts regarding soil erosion and loss of topsoil and no new and/or modified m itigation measures are required for issues related to geological hazards.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
7(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?
7(d) Be located on expansive soil, as defined in Table 18 -1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property? No New or More Significant Impact: As addressed in Impact 7(a) above, the Project would not be located near an Alquist -Priolo Fault Zone. Instead, the sites included in the Project would be within urbanized areas that are less susceptible to unstable soils. Therefore, no new or more significant impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
7(e) Soil capability to support waste water disposal, including septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water?
No New or More Significant Impact: All future housing development facilitated by the HEU would remain in areas served by the City’s sanitary sewer system and would therefore not use septic tanks or other alternative wastewater disposal systems. Therefore, the Project would result in no new or mo re severe impacts regarding waste water disposal and no new and/or modified mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

7(f) Directly or indirectly destroy a uniq ue paleontological resource or site or unique geologic feature?
No New or More Significant Impact : As previously mentioned, the Project would not result in direct housing construction, but would facilitate and provide a policy framework for future housing development. The m ajority of the candidate housing sites would remain on developed sites and all housing development facilitated by the Project would be designed consistent with the applicable guidelines and standards within the Rialto GP, Rialto MC, and CBC. Paleontological resources are further discussed in Impact discussions 5(a-c) above. No new or more severe impacts are expected.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to geological resources.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

GREENHOUSE GAS EMISSIONS
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would increase potential pedestrian activities through the expansion of residential units in transit areas. As well, new developments facilitated by the Project would be required to comply with applicable federal, state, and local regulations regarding GHG emission as a result of increase in greenhouse gas emissions (GHG) due to increased vehicle miles traveled (VMT). Additionally, the Rialto HEU would be required to comply with energy efficiency regulations .

Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
8(a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
8(b) Conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of greenhouse gases.

No New or More Significant Impact. The Project would not involve the facilitation of a greater amount of housing units in comparison to those analyzed in the Approved ISMND. The units facilitated by the Project would be within the footprint of those analyzed in the Approved ISMND. While the Project would indirectly facilitate the development of future housing units, the additional units would be required to complete environmental analysis prior to their development in order to ensure their minimal impact to the surrounding environment. Furthermore, new developments facilitated by the Project would be required to comply with applicable federal, state, and local regulations regarding GHG emission s. This includes policies instituted by SCAQMD in which developers would be required to comply with one of five exclusion tiers in order to avoid significant environmental impacts.

This Project would function similarly to the Rialto HEU analyzed in the Approved ISMND in that the Project would constitute policy changes which do not minimize or remove requirements for future developments to comply with greenhouse gas regulations or energy policies. Therefore, there are no new or more severe impacts.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to GHG.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

HAZARDS AND HAZARDOUS MATERIALS
Summary of Previous Environmental Analysis
The Approved ISMND concluded that due to the Rialto HEU’s lack of physical components, a minimal risk of exposure to hazardous materials would occur. Additionally, the Rialto HEU would not include designs which would impair the implementation of an emergen cy response plan, or evacuation plan. The Approved ISMND found no impact in relation to airport land use plans or cortese list sites. Mitigation was proposed in the Approved ISMND in order to minimize potential effects from accidental releases of hazardous materials from future developments facilitated by the Rialto HEU.

Future housing development assessed in the Approved ISMND would be required to comply with any relevant local, state, and federal regulations regarding energy usage. Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
9(a) Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
No New or More Significant Impact. The Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City . However, future development would include common construction practices like structure demolition, which often involve the use or handling of hazardous materials such as asbestos containing materials, lead -based paint, and/or contaminated soils . Future development within the City would be required to comply with regulations put in place by the State Department of Toxic Substances Control (DTSC). In their operation, future housing developments are not expected to utilize substantial or severe hazardous materials. Anticipated materials include cleaning solvents, fertilizers, pesticides, and other materials used in regular maintenance. No new or more severe impacts associated with the transport, use, or disposal of hazardous materials are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
9(b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
9(c) Emit hazardous emi ssions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? No New or More Significant Impact. The Project would not involve the physical development of housing units. However, the Project would facilitate future housing development throughout the City, including in urbanized areas and areas within 0.25 miles of a school. Therefore, excavation and grading activities associated with future housing development could expose construction workers and the general public to unknown hazardous materials present in soil or groundwater. MM HAZ -1 from the Approved ISMND would be implemented to ensure that future housing facilitated by the Project would be assessed with a Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

project-specific Phase I Environmental Site Assessment (ESA) for any property currently or historically involving hazardous materials or waste.

Additionally, future developments facilitated by the Project would be required to comply with all applicable Federal, State, and local regulations concerning hazardous materials , including the City’s development review process, and be subject to compliance with the established regulatory framework for minimizing upset associated with hazardous materials. New housing development may also be subject to CEQA review, and be required to comply with Rialto GP policies, and Rialto MC standards related to the emissions or handling of hazardous materials, substances, or wastes near schools to reduce the potential for impacts to schools. With the implementation of MM HAZ-1, no new impact or increase in the severity of an identified impact would therefore occur with implementation of the Project.

Mitigation Program
Mitigation Measures from the Approved ISMND
MM HAZ-1 from the Approved ISMND would be applied to this impact.

MM HAZ-1 Prior to any renovation, or demolition, grading or building permit approval, the applicant shall retain a qualified hazardous materials Environmental Professional to prepare a formal Phase I Environmental Site Assessment (ESA) for any vacant, commercial, and industrial properties involving hazardous materials or waste. The Phase I ESA shall be prepared in accordance with ASTM Standard Practice E 1527 -13 or the Standards and Practices for All Appropriate Inquiry (AAI), prior to any land acquisition, demolition, or construction activities. The Phase I ESA would identify specific Recognized Environmental Conditions (RECs), which may require further sampling/remedial activities by a qualified hazardous materials Environmental Professional with Phase II/site characterization experience prior to land acquisition, demolition, and/or construction. The Environmental Professional shall identify proper remedial activities to be implemented by the applicant, if necessary.
9(d) Be located on a site which is included on a list of hazardous mate rials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a significant hazard to the public or the environment?
No New or More Significant Impact. Government Code §65962.5 (commonly referred to as the Cortese List) includes DTSC -listed hazardous waste facilities and sites, Department of Health Services lists of contaminated drinking water wells, sites listed by the SWRCB as having underground storage tank leaks and having had a discharge of hazardous wastes or materials into the water or groundwater and lists from local regulatory agencies of sites that have had a known migration of hazardous waste/material. As concluded in the Approved ISMND, the Project area is not included on the hazardous sites list compiled pursuant to California Government Code §65962.5. No new impact or increase in the severity of an identified impact would therefore occur with implementation of the Project.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

9(e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard or excessive noise for people residing or working in the Project area?
No New or More Significant Impact. No portion of the City is within an airport land use plan. Additionally, there are no public airports or public use airports within two miles of the City. The Rialto Airport, previously known as Miro Field, was closed in 2014. Therefore, no new impact or increase in the severity of an identified impact would therefore occur with implementation of the Project.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
9(f) Impair implementation of an emergency response plan or emergency evacuation plan? No New or More Significant Impact . The Project proposes modifications to City regulations regarding housing development which would allow for expanded residential development potential throughout the City, largely in urban areas. The increased housing density associated with this Project may increase emergency response demands during evacuation periods. However, this Project would not directly result in modifications to circulation systems or methods for responding d uring periods of emergency.

Furthermore, future developments would be required to undergo City review which establishes consistency with applicable building and access regulations as well as fire abatement policies. Therefore, no new or more severe impact would occur as a result of the Project.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
9(g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
No New or More Significant Impact. Refer to Section 20: Wildfire.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND after implementation of MM HAZ-1. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to hazards or hazardous materials.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

HYDROLOGY AND WATER QUALITY
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would result in a less than significant impact to hydrology and water quality resources. This was attributed to the use of existing regulation and best management practices (BMPs) such as the reception of a National Pollutant Discharge Elimination System (NPDES) permit and a Storm Water Pollution Prevention Plan (SWPPP). Further, the City’s lack of hazardous geological features reduced potential impacts. Impacts were determined to be les s than significant with no mitigation required.

Analysis of Proposed Project
10(a) Violate water quality or waste discharge requirements or otherwise substantially degrade surface or groundwater quality?
10(e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
No New or More Significant Impact. As discussed in the Approved ISMND, f uture housing development could result during the earthwork and construction phase, f ollowing construction, before the establishment of ground cover, and after project completion, when impacts related to sedimentation would decrease markedly but those associated with urban runoff would increase. The construction of future housing units facilitated by the Project may generate erosion, siltation, and sedimentation which could then discharge into storm drains, and in most cases, flows directly to creeks, rivers, lakes, and the ocean.

To combat this, the Project would comply with policies such as those requiring the obtainment of an NPDES permit and SWPPP. Furthermore, each development would be required to complete the City’s development review process, which includes review pursuant to CEQA, and the prov ision of a Construction Activity General Permit associated with a SWPPP. City policies including the City’s Storm Water Management and Discharge Control Ordinance (Rialto MC §12.60.260 ) and the Rialto GP would need to be adhered to in order to minimize potential impacts. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
10(b) Substantially decrease groundwater supplies or i nterfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the basin?
No New or More Significant Impact . The City’s potable water supply is served by three water agencies:
the City of Rialto Dep artment of Public Works Water Division, the West Valley Water District (WVWD), and the Fontana Water Company (FWC) . The City’s primary source of water is City -owned water wells.

These wells draw water from four water basins: Lytle Creek Surface Water Basin , Rialto Ground Water Basin, Bunker Hill Ground Water Basin, and Chino Hill Ground Water Basin. As stated in the Approved Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

ISMND, each of these basins has an established safe yield limit to prevent over drafting of groundwater resources. Water districts are not permitted to extract beyond safe yield limits and will not be able to over the long-term and therefore would be assessed for each new housing development.

The facilitated housing development associated with the Project would additionally increase the City’s volume of impervious surfaces. However, each unit would be required to comply with Rialto MC’s Title 18 which includes landscape standards which ensures a reasonable amount of pervious landscaping surface.

Additionally, implementation of BMPs would further ensure proper infiltration practices. Therefore, no new or more sever impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
10(c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) Result in substantial erosion or siltation on- or off-site? ii) Substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or off-site?
iii) Create or contribute runoff water which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff?
iv) Impede or redirect flood flows?
No New or More Significant Impact . The Project would not result in direct housing construction . A majority of the Project site is developed and contain s impervious surfaces, which direct surface flows toward existing City facilities. The City is largely developed for urban uses and therefore contains existing drainage facilities and features which are adjusted to urban development. Furthermore, all future housing development facilitated by the HEU would be subject to the City’s development review process, which may include review pursuant to CEQA, and be required to comply with GP policies, Rialto MC standards, and required to adhere to all federal, state, and local requirements for avoiding impacts that could substantially alter the existing drainage pattern or alter the course of a stream or river, including the City’s Stormwater Management and Discharge Control Ordinance (Rialto MC §12.60.260). Therefore, no new or severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

10(d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundations?
No New or More Significant Impact. As established in the Approved ISMND City of Rialto is located approximately 45 miles inland from the Pacific Ocean. Given the distance from the coast, the potential for the Project site to be inundated by a large, catastrophic tsunami is extremely low. No steep slopes are in the vicinity of the City; therefore, the risk of mudflow is insignificant. Additionally, as previously noted the Federal Emergency Management Agency (FEMA) identifies most of the City of Rialto to be in Flood Hazard Zone X, which is identified as 500 -year Floodplain, an area of minimal flood hazard. This, in combination with future developers’ requirements to comply with the City’s development review process and any state or federal regulations, which may include review pursuant to CEQA , would minimize potential risks.

Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation meas ures are required for issues related to hydrology or water quality.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

LAND USE AND PLANNING
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would create a less than significant impact relative to land us e and planning since the Rialto HEU would act as a State mandated planning document to provide guidance to the City’s housing and population growth.

Analysis of Proposed Project
11(a) Physically divide an established community?
No New or More Significant I mpact: The Project does not result in direct housing construction and all future housing development facilitated by the HEU would be subject to the City’s development review process and would occur as market conditions allow and at the discretion of the in dividual property owners. As previously mentioned, the City is predominantly urban ized and future housing development would mostly occur in developed areas currently zoned as residential. Additionally, future housing development would not likely require su bstantial road-widenings or other features which could divide communities due to the developed status of the City . Therefore, the Project would not result in new or more severe land use impacts regarding the division of an established community.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
11(b) Conflict with any applicable land use plan, policy , or regulation of an agency with jurisdiction over the project (including, but not limited to the general plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect?
No New or More Significant Impact : The Project proposes modifications to the City’s General Plan and zoning code. Upon implementation the Project would be a part of the City’s planning regulations and would provide guidance on future growth within the City. The documents would be prepared in accordance with all applicable City permit standards as well as any state regulations such as CEQA review.

Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigati on measures are required for issues related to land use or planning.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

MINERAL RESOURCES
Summary of Previous Environmental Analysis
The Approved ISMND concluded that no impact would occur from the implementation of the Rialto HEU due to the lack of physical components associated with the Project and the lack of policy proposals related to mineral resources.

Analysis of Proposed Project
12(a & b) Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state? And result in the loss of availability of a locally-important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan?
No Impact. The Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development throughout the City. As previously noted, future housing development facilitated by the HEU may be subject to discretionary permits, including the City’s development review process, environmental review under CEQA, as well as, required to comply with applicable federal, state, and local laws and local p olicies and regulations, as applicable to new housing development. Therefore, no direct physical environmental impact would occur as a result of the implementation of the Project.

Standard Conditions and Requirements
None are applicable to the project.

No New or More Significant Impact : The Project directly proposes no new development within the City and instead provides guidance and framework for future housing development . No policy amendments included in the Project pertain to mineral resources. However, future housing development facilitated by the HEU may be subject to discretionary permits, including the City’s development review process, environmental review under CEQA, as well as, required to comply with applicable federal, state, and local laws and local policies and regulations, as applicable to new housing development.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to mineral resources.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

NOISE
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would result in a less than significant impact related to noise. This was attributed to the lack of physical development proposed in the Rialto HEU. Further, the imprecise timing of future housing development allowed for stratified timing. Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
13(a) Generation of a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance or applicable standards of other agencies? 13(b) Generation of excessive ground borne vibration or ground borne noise levels? No New or More Significant Impact. The project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development throughout the City. Future housing development facilitated by the HEU would result in construction noise generat ed from development activities.

Future activities associated with housing development would generally involve site preparation and/or demolition; grading and utilities construction; building construction; paving; and architectural coatings.

Typical construction equipment would include backhoes, excavators, graders, loaders, compactors, cranes, trucks, pavers, pneumatic tools, generator sets, and air compressors. Pile driving is the only activity anticipated to generate notable noise or vibrations. However, as assessed in the Approved ISMND, future development facilitated by the Project would occur in incremental phases over time based on market demand, economic, and planning considerations. As a result, cons truction-related noise would not be concentrated in any one particular area of the City.

However, all future housing development facilitated by the HEU would be subject to the City’s development review process, which may include compliance with the Rialto MC §9.50.070 (Disturbances from construction activity) and conditions of approval to include measures under its Design Review process such as temporary sound barriers and shielding to reduce potential noise impacts on sensitive receptors. Operational noise and groundborne vibration would be generated by stationary operation - related sources as well as increase traffic volume on local roadways. Despite this, the increase in density is not anticipated to change the overall impact of growth in the City compared to what was assumed in the Rialto GP and SCAG’s Connect SoCal RTP/SCS. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

13(c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels?
No Impact. Currently, there are no airports within the City of Rialto. The Project does not conflict with airport land use plans nor does it promote development near any airports. The closest airport is the San Bernardino International Airport which is greater than two (2) miles away. Therefore, no new or more severe impact is anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND along with a no impact determination. The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to noise.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

POPULATION AND HOUSING
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would result in a less than significant impact related to population and housing. This was attributed to the Rialto HEU association with State required housing policy. Further, the Rialto HEU did not directly propose any housing units. Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
14(a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)?
No New or More Significant Impact. Similar to the Rialto HEU analyzed in the Approved ISMND , the Project would not result in direct housing construction but would facilitate and provide a policy framework for future housing development within the City . The Approved ISMND assessed the Rialto HEU’s associated 5,600 units generated through rezoning along with th e 128 Accessory Dwelling Units (ADUs) which would generate a total of 5,728 housing units that would exceed the City’s planned capacity based on existing zoning standards or entitled private specific plans . Despite increasing the planned density of the Opp ortunity Areas, t he Project would remain consistent with the assumed density and potential maximum buildout limitations assessed in the Rialto HEU and Approved ISMND. Therefore, potential population effects would remain the same. Table 14 -1: Population Est imate Comparison below summarizes the estimates included in the Approved ISMND and, subsequently, those associated with the Project.

Table 14-1: Population Estimate Comparison
Definition Rialto
HEU
Maximum Potential Candidate Housing Units 16,368
Potential Candidate Housing Units through Existing Zoning, excluding ADU -10,640 New Housing Units Not Previously Planned For, with ADU 5,728 Persons per household (American Community Survey, 5-Year Estimates, 2019) 3.94
Forecasted Unplanned Population Growth – 2030 Horizon with Rialto HEU/Project 22,568
Existing 2020 Population Estimate 104,110
Existing 2020 Population – 2030 Horizon with Rialto HEU/Project 126,678 Forecast Unplanned Population Growth with Rialto HEU/Project Percentage 21.7% SCAG Forecast 2040 Population for City 112,000
Forecast 2030 Population for City – Extrapolated (based on constant growth rate 2020-2040) 108,055
Forecast 2030 Population for City – Extrapolated with Rialto HEU/Project 130,623 Forecast 2030 Population for City – Extrapolated with Rialto HEU/Project Percentage 21%
Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

It was noted that this growth would occur in urbanized locations near existing utilities and service systems, and areas already served by public services (e.g., police and fire protection, and other emergency responders).

As shown in Table 14-1, Population Estimate Comparison, the Project is estimated to generate population growth in the City by approximately 22,570 persons, consistent with the Approved ISMND. The majority of sites included in the Project were identified as a component of Statewide housing legislation, with only 290 dwelling units specific to this Project . Housing growth and population growth associated with the portions of the Project identified in the Rialto HEU would be in compliance with State-level regulation and would therefore not be considered unplanned. Future development facilitated by the Project would apply the implementing actions included in the Rialto HEU to increase the City’s housing capacity. Additionally, since the Project does not directly propose housing development within the City, the growth would occur based on market conditions over an extended peri od (i.e., 2021 through 2029). Furthermore, all future housing development facilitated by the Project would be subject to a development review process along with all Federal and State requirements (such as CEQA) in order to assess each development’s potenti al effects concerning population growth. Additionally, t he Project would continue to increase affordable housing units within the City which would provide housing opportunities in proximity to jobs for those employed within the City that meet these househo ld income categories. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
14(b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?
No New or More Significant Impact. The Project would minimally increase the City’s potential housing stock and therefore would minimally increase housing availability for residents. The Project assum es future housing units would be developed within the City in acceptable areas. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to population and housing.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

PUBLIC SERVICES
Summary of Previous Environmental Analysis
The Approved ISMND concluded that since the Rialto HEU would have no direct physical effects on the environment and would not directly propose the development of additional housing, impacts related to public services would remain less than significant. Additionally, the analysis repeated that the Rialto HEU would not preclude future development from undergoing the City’ s full development review and participating in any applicable development impact fees.

Analysis of Proposed Project
15(a) Fire Protection?
15(b) Police Protection?
15(c) Schools?
15(e) Other public facilities?
No New or More Significant Impact: The Project does not propose or require construction of any new or physically altered fire protection, police protection, schools, or other public facilities. As previously mentioned, the Project does not result in direct housing construction and all future housing development facilitated by the Project would be subject to the City’s development review process. Future development facilitated by the Project would be reviewed by applicable local agencies to ensure compliance with Rialto GP, Rialto MC, and Title 24 CBC standards, policies, and regulations. This includes developer fees which are distributed to City services such as fire and police protection facilities as well as school fees imposed through the education code.
15(d) Parks?
Less Than Significant Impact. Please refer to Section 16: Recreation below.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to public services.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

RECREATION
Summary of Previous Environmental Analysis
The Approved ISMND concluded that impacts to recreation facilities would be less than significant due to the Rialto HEU’s lack of directly proposed physical improvements. However, future developers would be required to adhere to any applicable recreational land development codes associated with residential development.

Analysis of Proposed Project
16(a) Increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?
16(b) Include recreational facilities or require the c onstruction or expansion of recreational facilities which might have an adverse physical effect on the environment? No New or More Significant Impact : While the Project would not directly propose the development of additional housing units, it may facilitate and does provide a policy framework for future housing development on candidate housing sites throughout the City, which are situated in urbanized areas .

However, these future developments would be built according to market conditions and at the discretion of the individual property owners. The Project sites are organized in a dispersed pattern through the City which allows for the minimization of potential demand for any specific recreation amenity. Additionally, it is possible that future developments would include the construction of recreational facilities and developer-produced parks, but it is presently unknown until future housing projects are proposed.

However, the Project does not include physical construction and future housing projects proposed would be reviewed by the City. Therefore, no new or more sever e impacts would occur and no new and/or modified mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to recreational resources.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

TRANSPORTATION
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would result in a less than significant impact to transportation resources. This was attributed to the requirements for future development to adhere to City regulations and safety policies. Additionally , the Rialto HEU was assessed as proposing no direct physical modifications within the City . Impacts were determined to be less than significant with no mitigation required.

Analysis of Proposed Project
17(a) Conflict with a program plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities? No New or More Significant Impact . The Approved ISMND established that a Project of this type would not result in direct housing construction but would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City. The Project does not include any goals, policies, or implementation programs that would conflict with plans or other regulations that address the circulation system. Future development projects would be reviewed on a case -by-case basis to verify consistency with applicable regulations that address the circulation system. The Project does not propose additional components which would contradict what was established in the Approved ISMND.

Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
17(b) Would the project conflict or be inconsistent with CEQA Guidelines section 15064.3, subdivision (b)?
No New or More Significant Impact . As established in the Approved ISMND, a ll future housing development facilitated by the Project would be required to adhere to all State and local requirements for avoiding significant impacts related to VMT. Any traffic demand measures required for mitigation would be required to comply with Rial to GP Goals 4.1 and 4.2, which encourage the maintenance of efficient roadway capacities and minimization of traffic hazards near residential uses. The expansion of housing units within urbanized areas is anticipated to reduce travel times and therefore generally reduce the City’s average VMT. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

17(c) Substantially increase hazards due to a geometric d esign feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? No New or More Significant Impact . Due to the urbanized status of the majority of the Project site, existing roadways that are expected to continue being used as they have been previously connected and adjacent to the existing transportation network. Therefore, hazards due to a geometric design feature or incompatible uses are not anticipated. The Project would be consistent with the Approved ISMND in this regard. Therefore, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
17(d) Result in inadequate emergency access?
No New or More Significant Impact. See impact response 9(f) above. The Project proposes modifications to City regulations regarding housing development which would allow for expanded residential development potential throughout the City, largely in urban areas. The incre ased housing density associated with this Project may increase emergency response demands during evacuation periods.

However, this Project would not directly result in modifications to circulation systems or methods for responding during periods of emergen cy. Furthermore, future developments would be required to undergo City review which establishes consistency with applicable building and access regulations as well as fire abatement policies. Therefore, no new or more severe impact would occur as a result of the Project.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to transportation.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

TRIBAL CULTURAL RESOURCES
Summary of Previous Environmental Analysis
The Approved ISMND included initial consultation with tribes identified through Assembly Bill 52 (AB 52) and Senate Bill 18 (SB 18) . SMBMI contacted the City via e -mail requesting additional doc uments and a consultation. No tribes requested further consultation and the Approved ISMND concluded a less than significant impact to tribal resources would occur.

Analysis of Proposed Project
18(a) Would the project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
i) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code Section 5020.1(k)?
ii) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1. In applying the criteria set forth in subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe? No New or More Significant Impact. The Project contains the same footprint as the Rialto HEU . Through the Approved ISMND , no tribes contacted the City to notify them of nearby cultural resources.

Furthermore, future earthmoving development would be required to undergo City review practices a s well as CEQA analysis which includes additional tribal consultation. Additionally, MM TCR-1 and MM TCR- 2 from the Approved ISMND will be applied to the Project to ensure proper handling of Tribal Cultural Resources. Therefore, with the implementation of mitigation s, no new or more severe impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
MM TCR-1 and MM TCR-2 from the Approved ISMND will be applied to the Project.

MM TCR-1 The San Manuel Band of Mission Indians Cultural Resources Department (SMBMI) shall be contacted, as detailed in MM CUL-1 of any pre -contact and/or post-contact cultural resources discovered during future housing development, and be provided information regarding the nature of the find, so as to provide Tribal input with regards to significance and treatment. Should the find be deemed significant, as defined by CEQA (as amended, 2015), a cultural resource Monitoring and Treatment Plan shall be created by the archaeologist, in coordination with the SMBMI, and all subsequent finds shall be subject to this Plan. This Plan shall allow for a monitor to be present that represents the SMBMI Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

for the remainder of the future housing developm ent, should either of the Consulting Tribes elect to place a monitor on-site.

MM TCR-2 Any and all archaeological/cultural documents created as a part of the future housing development (isolate records, site records, survey reports, testing reports, etc.) shall be supplied to the future project-specific applicant, and the City for dissemination to SMBMI.

The City and/or applicant shall, in good faith, consult with the Consulting Tribes throughout the life of the future housing project.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to tribal cultural resources.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

UTILITIES AND SERVICE SYSTEMS
Summary of Previous Environmental Analysis
The Approved ISMND concluded that the Rialto HEU would have a less than significant impact in regard to utilities and service systems within the City. This determination was due to the requirement for future housing developments facilitated by the Rialto HEU to comply with necessary regulations including those for wastewater facility usage, state recycling programs, and water usage minimization.

Analysis of Proposed Project
19(a) Require or result in the relocation or construction of new or expanded water, wastewater treatment, or storm water drainage, electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects?
No New or More Significant Impact: The Project does not directly propose housing construction and all future housing development facilitated by the Project would be subject to the City’s development review process as well as potential CEQA review.

Further, most of the candidate housing sites are developed and connect to existing water and dry utility infrastructure within the City. No new significant expansion of infrastructure facilities are required as a component of this Project.

Additionally, future development may be required to implement a SWPPP to ensure that water quality is not degraded, and that storm water flows from the site in a manner that does not exceed wastewater treatment requirements. Future hous ing development would also be required to adhere to all federal, state, and local requirements related to wastewater treatment during construction and operations, including the City’s Sewer System guidelines (Rialto MC §12.08) and required construction permits.

The housing development facilitated by the Rialto HEU would increase the demands for dry utilities.

However, the candidate housing sites are located in developed areas of the City that are already served by electric power, natural gas, and telecommu nications facilities. Additionally, future housing development would not substantially increase population within the City to the point of substantial increase of service demands. The City’s growth projections are consistent with regional and local plans used to guide infrastructure development. The Project would result in no new or more severe impacts as it pertains to placement of utilities and sewer systems, or wastewater treatment capacity and no new and/or modified mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
19(b) Have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry and multiple dry years? No New or More Significant Impact . The Approved ISMND calculated potential water needs based on 5,728 new housing units. The Rialto HEU’s addition of 5,728 housing units and its associated population Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

growth of approximately 22,568 persons was applied to the City’s 10 -year average base daily per capita water usage rate of approximately 214 gallons per day (gpd). This average was provided through the 2015 San Bernardino Valley Regional Urban Water Management Plan (UWMP).17 Using the average, the Rialto HEU was calculated to generate an estimated demand of 4,829,552 gpd or approximately 5,410 acre-feet (AF) of water per year (AFY).

The 2015 UWMP noted that d uring dry years, the City is able to source up to 9,066 AF of water from groundwater sources and 7,500 AF of imported water, bringing the dry year total to 14,566 AF. The Rialto HEU was calculated to comprise approximately 37 percent of the City’s dry-year water supply. The Project, would facilitate the same estimated number of housing units due to each Opportunity Area’s realistic maximum potential buildout.

Note that as stated in the Approved ISMND, future development would occur incrementally through 2029, based on market conditions and other factors, such that existing water services are not overburdened by substantially increased demands at any given time. Future development satisfying certain criteria would require preparation of a Water Supply Assessment (WSA) in order to verify sufficient water supply is available to meet the develop ment’s water demand. The Project would be similarly limited as the Approved ISMND in its ability to directly generate water demand. Therefore, no new or more significant impact is anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.
19(c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project projected demand in addition to the provider’s existing commitments?
Less Than Significant Impact. Akin to the Rialto HEU, future housing development under the Project may be subject to discretionary permits and be required to adhere to all federal, state, and local requirements related to wastewater treatment during construction and operations, including the City’s Sewer System guidelines (Rialto MC §12.08) and required construction permits. As well, the Project would remain consistent with the Approved ISMND. Considering these requirements, and the available capacity discussed above, the Project would not result in a determination by the wastewater treatment provider that it has inadequate capacity to serve the Pr oject’s projected demand in addition to the provider’s existing commitments. No new or more significant impacts are anticipated.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

17 Water Systems Consulting. (2006) 2015 San Bernardino Valley Regional Urban Water Management Plan. Pages 41-1 through 14-14.

Retrieved from https://wvwd.org/wp-content/uploads/2018/03/SBV_RUWMP_rev_with_appendices_1.pdf (Accessed December 1, 2022) Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

19(d) Generate solid waste in excess of State or local standards, or in excess of the capacity of local infrastr ucture, or otherwise impair the attainment of solid waste reduction goals?
19(e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
Less Than Significant Impact. The Project would facilitate the same housing development as analyzed in the Approved ISMND, it is not expected that future projects would lead to inadequate landfill capacity at the Mid-Valley Sanitary Landfill, which has a daily capacity of 7,500 tons per day. The landfill has the capacity for 101.3 million cubic yards and has an operational life through 2033. Solid waste generated via future housing developments facilitated by the Project is anticipated to be the same as those analyzed in the Approved ISMND. Existing landfill capacity would be sufficient to serve future development within the City. Therefore, no new or more significant impacts would occur.

Additionally, all future construction activities would be required to demonstrate compliance with federal, State, and local statutes and regulations for solid waste. Construction activities would be subject to compliance with the 50 percent diversion of solid waste requirement pursuant to the California Integrated Waste Management Act of 1989 (AB 939). This is taken further by AB 341 which requires Cities and Counties to implement recycling programs, reduce refuse at the source, and compost waste to achieve the established 75 percent diversion of solid waste from landfills. As well, construction activities would be required to comply with the most recent Green Building Code, which implements design and construction measures that act to reduce construction -related waste through material conservation measures and other construction-related efficiency measures.

Finally, future housing development facilitated by the Project may be subject to discretionary permits and be required to adhere to all federal, state, and local requirements for solid waste reduction and recycling.

Therefore, no new or more significant impacts would occur.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to utilities or service systems.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

WILDFIRE
Summary of Previous Environmental Analysis
The Approved ISMND concluded that no candidate sites identified for the Rialto HEU occur within a State Responsibility Area (SRA) or a Very High Fire Hazard Severity Zone (VHFHZ), except those in the LCRSP .

Future development facilitated by the Rialto HEU would also require additional City and CEQA review for wildfire risk. The Approved ISMND determined that the Rialto HEU posed a less than significant impact related to wildfire.

Analysis of Proposed Project
20(a) If located in or near state responsibility area or lands classified as very high fire hazard severity zones, would the project substantially impair an adopted emergency response plan or emergency evacuation plan?
20(b) Due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to, pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
20(c) Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment? 20(d) Expose people or structures to significant risks, including downs lope or downstream flooding or landslides, as a result of runoff, post- fire slope instability, or drainage changes?
No New or More Significant Impact. Although the project would not result in direct housing construction, it would facilitate and provide a policy framework for future housing development on candidate housing sites throughout the City . The Project does not include sites located in LCRSP and as such there are no Project housing sites located in or near an SRA or lands classified as VHFHSZ. Therefore , Project implementation would not result in any new or more severe impacts with respect to Wildfire and no new and/or modified mitigation measures are required.

Mitigation Program
Mitigation Measures from the Approved ISMND
None identified in the Approved ISMND.

Conclusion
The Project would result in no new or more severe impacts. A less than significant impact was identified in the Approved ISMND . The Project would be consistent with the analysis contained in the Approved ISMND. Therefore, no new and/or modified mitigation measures are required for issues related to wildfire.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

5.0 DETERMINATION OF APPROPRIATE CEQA DOCUMENTATION
The following discussion lists the appropriate subsections of Sections 15162 and 15164 of the CEQA Guidelines and provides ju stification for the City to make a determination of the appropriate CEQA document for the Project, based on the environmental analysis provided above.

CEQA Guidelines Section 15162 ‒ Subsequent EIRs and Negative Declarations (a) When an EIR has been certif ied or a negative declaration adopted for a project, no subsequent EIR shall be prepared for that Project unless the lead agency determines, on the basis of substantial evidence in light of the whole record, one or more of the following:
(1) Substantial ch anges are proposed in the Project which will require major revisions of the previous EIR or negative declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects.

The City proposes to implement the Project within the context of the Approved ISMND , as described in this Addendum. As discussed in the Environmental Impact Analysis section of this Addendum, no new or more severe significant environmental effects beyond what was evaluated in the Approved ISMND would occur.
(2) Substantial changes occur with respect to the circumstances under which the project is undertaken which will require major revisions of the previous EIR or negative declaration due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects.

As documented herein, no circumstances associated with the location, type, setting, or operations of the Project have substantively changed beyond what was evaluated in the Approved ISMND; and none of the Project elements would result in new or more severe significant environmental effects than previously identified. No major revisions to the Approved ISMND are required. (3) New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time the previous EIR was certified as complete or the negative declaration was adopted, shows any of the following:
(A) The project will have one or more significant environmental effects not discussed in the previous EIR or negative declaration;
No new significant environmental effects beyond those addressed in the Approved ISMND were identified.
(B) Significant effects previously examined will be substantially more severe than shown in the previous EIR;
The Approved ISMND identified no significant effects.
(C) Mitigation measures or alternatives previously found not to be feasible would in fact be feasible, and would substantially reduce one or more significant effects of the project, but the project proponents decline to adopt the mitigation measure or alternative; or No mitigation measures or alternatives were found infeasible in the certified Approved ISMND.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

(D) Mitigation measures or alternatives which are considerably different from those analyzed in the previous EIR would substantially reduce one or more significant effects on the environment, but the project proponents decline to adopt the mitigation measure or alternative.

No other mitigation measures or feasible alternatives have been identified that would substantially reduce significant impacts.
(b) If changes to a project or its circumstances occur or new information becomes available after adoption of a negative declaration, the lead agency shall prepare a subsequent EIR if required under subsection (a). Otherwise, the lead agency shall determine whether to prepare a subsequent negative declaration, an addendum, or no further documentation.

Subsequent to certification of the Approved ISMND in March 2022, additional technical analyses were performed for the Project and are the subject of this Addendum. Based on the analysis in this document, the Project would not result in any new signifi cant environmental effects, nor would it increase the severity of significant effects previously identified in the Approved ISMND . None of the conditions listed under subsection (a) would occur that would require preparation of a subsequent EIR. (c) Once a project has been approved, the lead agency’s role in project approval is completed, unless further discretionary approval on that project is required. Information appearing after an approval does not require reopening of that approval. If after the project is approved, any of the conditions described in subsection (a) occurs, a subsequent EIR or negative declaration shall only be prepared by the public agency which grants the next discretionary approval for the project, if any. In this situation, no other Responsible Agency shall grant an approval for the project until the subsequent EIR has been certified or subsequent negative declaration adopted.

None of the conditions listed in subsection (a) would occur as a result of the Project. No SEIR is required.

CEQA Guidelines Section 15164 ‒ Addendum to an EIR or Negative Declaration (a) The lead agency or responsible agency shall prepare an addendum to a previously certified EIR if some changes or additions are necessary, but none of the conditions described in Section 15162 calling for preparation of a subsequent EIR have occurred.

As described above, none of the conditions described in the CEQA Guidelines Section 15162 calling for the preparation of a SEIR have occurred.
(b) An addendum to an adopted negative declaration may be prepared if only minor technical changes or additions are necessary or none of the conditions described in Section 15162 calling for the preparation of a subsequent EIR or negative declaration have occurred.

None of the conditions described in Section 15162 calling for preparation of a subsequent EIR would occur as a result of the Project. Therefore, an addendum to the certified Approved ISMND is the appropriate CEQA document for the Project.
(c) An addendum need not be circulated for public review but can be included in or attached to the Approved ISMND or adopted negative declaration.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

This Addendum will be attached to the Approved ISMND and maintained in the administrative record files at the City.
(d) The decision-making body shall con sider the addendum with the Approved ISMND or adopted negative declaration prior to making a decision on the project.

The City will consider this Addendum with the Approved ISMND prior to making a decision on the Project. (e) A brief explanation of the dec ision not to prepare a subsequent EIR pursuant to Section 15162 should be included in an addendum to an EIR, the lead agency’s required findings on the Project, or elsewhere in the record. The explanation must be supported by substantial evidence.

This doc ument provides substantial evidence for City records to support the preparation of this Addendum for the Project.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

6.0 CONCLUSION
This Addendum has been prepared in accordance with the provisions of the CEQA Statute and the CEQA Guidelines to document the fin ding that none of the conditions or circumstances that would require preparation of a SEIR, pursuant to Section 15162 and Section 15164 of the CEQA Guidelines , exist in connection with the Project. No major revisions would be required to the Approved ISMND prepared for the Rialto HEU as a result of the Project. No new significant environmental impacts have been identified.

Since the certification of the Approved ISMND , there has been no new information showing that mitigation measures or alternatives once considered infeasible are now feasible or showing that there are feasible new mitigation measures or alternatives substantially different from those analyzed in the EIR that the City declined to adopt. Therefore, preparation of a SEIR is not required and the appropriate CEQA document for the Project is this Addendum to the Approved ISMND. This document will be maintained in the administrative record files at the City.

Housing Element Update Rezone Program
City of Rialto Initial Study/Mitigated Negative Declaration Addendum

7.0 REFERENCES
City of Rialto. (2010). City of Rialto General Plan . Pages 2 -4 through 2 -9. Re trieved from:
https://yourrialto.com/DocumentCenter/View/1494/2010-General-Plan. (Accessed November 30, 2022).

City of Rialto. 2021. City of Rialto 6th Cycle Housing Element Update (2021 -2029) Initial Study/Mitigated Negative Declaration. Retrieved from: https://www.yourrialto.com/DocumentCenter/View/ 2120/ISMND_Rialto-Housing-Element-Update
City of Rialto. 2022. Plan to House Our Rialto: 2021 -2029 Housin g Element Update . Retrieved from:
https://www.yourrialto.com/633/Plan-to-House-Our-Rialto-Housing-Element Southern California Association of Governments (SCAG). 2016 -2040 RTP/SCS Final Growth Forecast by Jurisdiction. Retrieved from: https://scag.ca.gov/sites/main/files/file-attachments/2016_ 2040rtpscs_finalgrowthforecastbyjurisdiction.pdf?1605576071 U.S. Geological Survey (USGS).2022. Domestic Names. Available at https://www.usgs.gov/us-board-on- geographic-names/domestic-
names?p=gnispq%3A3%3A%3A%3ANO%3A%3AP3_FID%3A1661306
United States Census Bureau. 2022. Quick Facts Rialto City, California . Retrieved from https://www.census.gov/quickfacts/rialtocitycalifornia

Appendix A
Mitigation Monitoring and Reporting Program
City of Rialto Housing Element Update Rezone Program Mitigation Monitoring and Reporting Program 1 CITY OF RIALTO HOUSING ELEMENT UPDATE REZONE PROGRAM

MITIGATION MONITORING AND REPORTING PROGRAM
Mitigation Measures Responsibility for
Implementation Timing Responsibility for
Monitoring
Monitor
(Signature Required)
(Date of Compliance)

BIOLOGICAL RESOURCES
MM BIO-1: A focused survey for burrowing owls shall be conducted by a qualified professional biologist for any new development project proposed on a vacant site of two acres or larger, with a landscape of annual and perennial grasslands, desert, or arid scrubland with low -growing vegetation. The purpose of the survey is to determine if burrowing owls are foraging or nesting on or adjacent to the project site. If surveys confirm that the site is occupied habitat, mitig ation measures to minimize impacts to burrowing owls, their burrows and foraging habitat shall be identified. The results of this survey, including any mitigation recommendations, shall be incorporated into the project -level CEQA compliance documentation.

Owl surveys and
approaches to mitigation shall be in accordance with the Staff Report on Burrowing Owl Mitigation, issued by the California Department of Fish and Game on October 17, 1995.

Future project
applicants
During
environmental
review prior to
construction
activities.

City of Rialto

CULTURAL RESOURCES
MM CUL-1: Archaeological Resources: For development projects or land use plans in areas determined to have a high potential for archaeological resources as determined through field surveys required by General Plan Policy 7-3.1, grading shall be monitored by trained archeological crews working under the direction of a qualified professional, so that resources exposed during grading can be recovered and the scientifically important information preserved. Archaeological monitors shall be equipped to recover resources as they are unearthed and to avoid construction delays. Monitors shall be empowered to temporarily halt or divert equipment to allow removal of abundant or large specimens. Qualified archaeological personnel shall prepare recovered specimens to a point of identification and permanent preservation. Qualified archaeological personnel shall identify and curate specimens into the collections of an appropriate, established, and accredited museum repository with permanent retrievable archaeological storage as determined in consultation with the Community Development Director.

Qualified archaeological personnel shall prepare a repo rt of findings with an appendix itemized of specimens subsequent to implementation of curation.

A preliminary report shall be submitted to and approved by the Community Development Director before granting of building permits and a final report shall be submitted to and approved by the Community Development Director before granting of occupancy permits
Future project
applicants
Prior to the granting
of occupancy
permits.
(preliminary report)

During construction
activities (specimen
identification)
Qualified archeological
personnel

Community Development
Director

City of Rialto Housing Element Update Rezone Program Mitigation Monitoring and Reporting Program 2 Mitigation Measures Responsibility for
Implementation Timing Responsibility for
Monitoring
Monitor
(Signature Required)
(Date of Compliance)
MM CUL-2: Paleontological Field Surveys: In areas containing middle to late Pleistocene era sediments (Qof ) where it is unknown if paleontological resources exist, field surveys prepared by a qualified paleontological professional before grading shall be conducted to establish the need for paleontologic monitoring. Should paleontological monitoring be required after recommendation by the professional paleontologist and approval by the Community Development Director, MM CUL-3 shall be implemented.

Future project
applicants
Prior to grading
activities
Community Development
Director

MM CUL-3: Paleontological Monitoring: A project that requires grading plans and is located in an area of known fossil occurrence or that has been demonstrated to have fossils present in a field survey as described in MM CUL-2 shall have all grading monitored by trai
ned paleontologic crews
working under the direction of a qualified professional, so that fossils exposed during grading can be recovered and preserved. Paleontologic monitors shall be equipped to salvage fossils as they are unearthed, to avoid construction delays, and to remove samples of sediments that are likely to contain the remains of small fossil invertebrates and vertebrates. Monitors shall be empowered to temporarily halt or divert equipment to allow removal of abundant or large specimens. Monitoring is not necessary if the potentially fossiliferous units described for the property in question are not present or if present are determined upon exposure and examination by qualified paleontologic personnel to have low potential to contain fossil resourc es.

Should paleontological resources require recovery, MM CUL -4 shall be implemented.

Future project
applicants
During construction
activities
Paleontological monitor
MM CUL-4: Paleontological Recovery, Identification, and Curation: Qualified paleontologic personnel shall prepare recovered specimens to a point of identification and permanent preservation, including washing of sediments to recover small invertebrates and vertebrates. Qualified paleontologic personnel shall identify and curate specimens into the collections of the Division of Geological Sciences, San Bernardino County Museum, an established, accredited museum repository with permanent retrievable paleontologic storage. The paleontologist must have a written repository agreement in hand prior to the initiation of mitigation activities. This measure is not considered complete until curation into an established museum repository has been fully completed and documented.

Qualified
paleontological
personnel
Prior to the
initiation of
mitigation activities
Division of Geological Sciences,
San Bernardino County
Museum

MM CUL-5: Paleontological Findings: Qualified paleontologic personnel shall prepare a report of findings with an appendix itemized of specimens subsequent to implementation of MM CUL -4. A preliminary report shall be submitted to and approved by the Community Development Director before granting of building permits and a final report shall be submitted to and approved by the Community Development Director before granting of occupancy permits.

Qualified
paleontological
personnel
Prior to the
issuance of grading
permits
Community Development
Director

City of Rialto Housing Element Update Rezone Program Mitigation Monitoring and Reporting Program 3 Mitigation Measures Responsibility for
Implementation Timing Responsibility for
Monitoring
Monitor
(Signature Required)
(Date of Compliance)
MM SMBMI -1: In the event that cultural resources are discovered during future housing development facilitated by the HEU activities, all work in the immediate vicinity of the find (within a 60 -foot buffer) shall cea se and a qualified archaeologist meeting Secretary of Interior standards shall be hired to assess the find. Work on the other portions of the project outside of the buffered area may continue during this assessment period. Additionally, the San Manuel Band of Mission Indians Cultural Resources Department (SMBMI) shall be contacted, as detailed within MM TCR -1, regarding any pre -contact and/or post-contact finds and be provided information after the archaeologist makes his/her initial assessment of the nature of the find, so as to provide Tribal input with regards to significance and treatment.

Future project
applicants
During construction
activities
San Manuel Band of Mission
Indians Cultural Resources
Department

MM SMBMI -2: During future housing development facilitated by the HEU activities, if significant pre-contact and/or post-contact cultural resources, as defined by CEQA (as amended, 2015), are discovered and avoidance cannot be ensured, the archaeologist shall develop a Monitoring and Treatment Plan, the drafts of which shall be provided to SMBMI for review and comment, as detailed within MM TCR-1. The archaeologist shall monitor the remainder of the project and implement the Plan accordingly.

Qualified
archeologist
During construction
activities
San Manuel Band of Mission
Indians Cultural Resources
Department

MM SMBMI-3: If human remains or funerary objects are encountered during any activities associated with future housing development facilitated by the HEU activities, work in the immediate vicinity (within a 100-foot buffer of the find) shall cease and the County Coroner shall be contacted pursuant to State Health and Safety Code §7050.5 and that code enforced for the duration of the project.

Future project
applicants
During construction
activities
County Coroner

HAZARDS AND HAZARDOUS MATERIALS
MM HAZ-1: Prior to any renovation, or demolition, grading or building permit approval, the applicant shall retain a qualified hazardous materials Environmental Professional to prepare a formal Phase I Environmental Site Assessment (ESA) for any vacant, commercial, and indust rial properties
involving hazardous materials or waste. The Phase I ESA shall be prepared in accordance with ASTM Standard Practice E 1527 -13 or the Standards and Practices for All Appropriate Inquiry (AAI), prior to any land acquisition, demolition, or construction activities. The Phase I ESA would identify specific Recognized Environmental Conditions (RECs), which may require further sampling/remedial activities by a qualified hazardous materials Environmental Professional with Phase II/site characterizat ion experience prior to land acquisition, demolition, and/or construction. The Environmental Professional shall identify proper remedial activities to be implemented by the applicant, if necessary.

Future project
applicants
Prior to the
issuance of
development
permits
City of Rialto
City of Rialto Housing Element Update Rezone Program Mitigation Monitoring and Reporting Program 4 Mitigation Measures Responsibility for
Implementation Timing Responsibility for
Monitoring
Monitor
(Signature Required)
(Date of Compliance)

TRIBAL CULTURAL RESOURCES
MM TCR -1: The San Manuel Band of Mission Indians Cultural Resources Department (SMBMI) shall be contacted, as detailed in MM CUL-1 of any pre- contact and/or post -contact cultural resources discovered during future housing development, and be provided information regarding the nature of the find, so as to provide Tribal input with regards to significance and treatment. Should the find be deemed significant, as defined by CEQA (as amended, 2015), a cultural resource Monitoring and Treatment Plan shall be created by the archaeologist, in coordination with the SMBMI, and all subsequent finds shall be subject to this Plan. This Plan shall allow for a monitor to be present that represents the SMBMI or the remainder of the future housing development, should either of the Consulting Tribes elect to place a monitor on-site.

Future project
applicants
During construction
activities
San Manuel Band of Mission
Indians monitor

MM TCR-2: Any and all archaeological/cultural documents created as a part of the future housing development (isolate records, site records, survey reports, testing reports, etc.) shall be supplied to the future project- specific applicant, and the City for dissemination to SMBMI. The City and/or applicant shall, in good faith, co nsult with the Consulting Tribes throughout the life of the future housing project.

Future project
applicants
Throughout project
development and
permitting
City of Rialto

San Manuel Band of Mission
Indians Cultural Resources
Department