Roseville City Council
October 7, 2026

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-13 Source: Image produced and provided by HDR in 2025; adapted by Ascent in 2025.

Figure 2-5 Proposed Phasing Plan

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-15

MSW RECEIPT AND TRANSFER
MSW consists of a mixture of all other wastes, including residential, commercial, and industrial wastes. MSW would be unloaded in the transfer area adjacent to the organics unloading area and near load-out chutes. The initial phase of the RRTO Facility would receive primarily commercially operated trucks such as the City’s waste collection fleet trucks and franchise/professionally operated trucks. The MSW waste unloading area would be located on the ‘commercial users,’ or west side of the building where City and franchise haulers would be directed for unloading. After unloading, MSW would be consolidated into a surge area and then loaded into transfer trucks for delivery/disposal elsewhere.

The MSW unloading area would be located in proximity to the centrally located large surge area, which would allow MSW to be consolidated by front-end loaders for staging prior to being pushed into either of the two loadout chutes provided at the north end of the RRTO Facility. Similar to the organic waste transfer operations, this proximity is intended to minimize the amount of time MSW remains staged in the building. Regulations require removal of MSW, organics, residue from recyclables processing, or any materials being sent for secondary processing to be removed within 48 hours, unless an alternative storage time has been approved.

The project would also include a household hazardous waste (HHW) receiving, storing, and shipping/transfer area.

HHW materials typically consist of leftover household products that can catch fire, react, or explode under certain circumstances, or those that are corrosive or toxic. This can include anything from paints, cleaners, pesticides, and oils to “universal wastes,” including batteries, electronics, and certain types of light bulbs. HHW would be received at the RRTO Facility in two ways: entrained in the mixed waste or recyclables materials streams or collected separately by the City’s HHW waste collection vehicles from residents and businesses within the City and delivered to the RRTO Facility. HHW materials observed in the arriving waste or recycling materials streams would be gathered by waste transfer or recycling staff and taken to the HHW area. Waste collection trucks that have obtained HHW from generators within the City and collected by the City would be received at the HHW area where the materials would be unloaded from the collection trucks.

The HHW area would occupy approximately 6,000 square feet of the waste transfer portion of the RRTO Facility.

HHW operators would receive these materials and categorize them into areas with compatible materials for temporary storage. Then, HHW operators would combine compatible materials or pack the materials into containers used to transfer the materials to a designated off-site facility where the materials would be properly disposed.

ORGANIC WASTE RECEIPT, PRE-PROCESSING, AND TRANSFER
Organic waste consists of a mixture of yard/garden wastes (also known as green wastes), food waste, and food soiled paper/packaging wastes. These materials comprise the organic materials required to be diverted from landfills pursuant to SB 1383. For Phase 1 of the project, organic wastes would be unloaded in the transfer building where they would be consolidated, with the likelihood that some level of contamination removal would be performed (including the use of de-packaging equipment, sorting equipment, or other technology deployment), and loaded into transfer trucks for delivery/processing elsewhere.

The organic wastes unloading area would be located close to one of the two loadout chutes provided in the new transfer facility. This proximity is intended to minimize the amount of time these materials remain in the building.

Regulations require MSW, organics, residue from recyclables or organics processing, or any materials being sent for secondary processing to be removed within 48 hours, unless an alternative storage time has been approved. The organic waste unloading area is located on the ‘commercial users,’ or west side of the building where City and franchise haulers would be directed for unloading.

RRTO FACILITY SITE CIRCULATION
Commercial unloading of material would be located on either or both sides of the RRTO Facility depending on facility needs. The flow of traffic arriving at the facility would include the receipt and management of the following traffic flows bringing materials to be unloaded:

Project Description Ascent
City of Roseville
2-16 Roseville Environmental Utilities Operations Center Project Draft EIR  City-collected organic waste and contracted organic waste from other regional jurisdictions or private haulers outside the city,
 City-collected MSW and contracted MSW from other regional jurisdictions or private haulers outside the city, and  City-collected recyclables and contracted recyclables from other regional jurisdictions or private haulers outside the city.

After entering though the entrance plaza, commercial vehicles would be directed either around the northern side of the RRTO Facility or through the RRTO Facility to unload their vehicle’s contents. Materials would be unloaded at three designated areas for: organic waste, MSW, and recyclables. Each of these areas are shown on Figure 2-4.

After unloading, the commercial vehicles would either be weighed again before departing, or if the vehicle has a tared value on file, the vehicle may depart the facility without being weighed out.

The flow of traffic at the facility would include the following traffic to remove materials from the site, including:
 organics to be transferred to an off-site facility for processing via one of the two top-load chutes in the transfer station portion of the RRTO Facility,
 MSW to be transferred to an off-site disposal area via one of the two top-load chutes in the transfer station portion of the RRTO Facility,
 recycled commodities to their respective industries/commodity recipients would be loaded out in the form of baled materials or loose in containers such as glass, and  household hazardous waste and related materials as appropriate.

Household hazardous waste would be collected and stored appropriately at the RRTO Facility and must be removed within 90 days by an authorized transporter/vendor.

2.4.2 Corporation Yard
The new Corporation Yard would be composed of two primary areas: EU Services Facility and the Equipment Maintenance Facility. As noted above, the City is outgrowing the current Hilltop Circle Corporation Yard. It intends to relocate some of its divisions to the new Corporation Yard on the project site. Roseville Electric and the Roseville Fire Department operate training centers at the existing Hilltop Circle Corporation Yard and are expected to remain at the current site for the foreseeable future. It is not known at this time if the City would move other employees or operations to or from the existing Hilltop Circle Corporation Yard. The various EU divisions that are being considered for relocation and consolidation to the new EU Operations Facility Corporation Yard location include EU Administration, Technical Services, Refuse and Stormwater Utility, and Water Utility functions.

EU SERVICES FACILITY
The EU Services Facility would consist of the corporation yard uses currently performed at Hilltop Circle, noted above, relocated to the project site. To meet these needs, the EU Services Facility is envisioned to include a combined Administration Office building to provide managerial oversite and support services for the EU department, which includes utility rate development, budgeting, accounting, reporting, and public information. The EU department also co-manages the Utility Exploration Center with Roseville Electric.

The EU Services Facility also includes office areas for the Technical Services division. Technical Services manages special projects and programs, including division-wide engineering, capital improvement projects, long-range planning, plan review, inspections, mapping and cataloging of existing and new City utility infrastructure, drafting, managing mapping and modeling program software, responding to public record act requests, enterprise asset management programming and rehabilitation planning, and division safety programs.

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-17 The EU Services Facility also includes the Refuse and Stormwater Utility division. This division provides residential and commercial refuse service and recycling programs and oversees the City’s stormwater quality program. For the relocation to the proposed site, the Refuse portion of this department would be located at the administration building.

The EU Services Facility would also provide space for the Water Utility division. This division provides surface and groundwater supply, water treatment, distribution, and water efficiency services. The division also oversees legislative and regulatory issues for the utilities.

In addition to an administrative office building and associated employee and visitor parking, the EU Services Facility would house enclosed storage for each of the division’s needs, including care of equipment and specialized tools.

The EU Services Facility would also include outdoor storage needs for each of the division’s materials, outdoor equipment, supplies, parts, pipes, and pumps.

EQUIPMENT MAINTENANCE FACILITY
The Equipment Maintenance Facility area provides for the parking, maintenance and repair, and fueling/charging of all the EU fleet needs, as well as an administrative office and parking for employees. It is located within the proposed Corporation Yard but would be centrally located between the RRTO Facility and the EU Services Facility to allow each of these divisions to easily access their respective fleet vehicles.

The Equipment Maintenance Facility area shown in Figure 2-4 includes parking for a fleet of up to approximately 400 fleet vehicles and equipment. Initially, the fleet parking area would allow the current waste and EU fleet of City vehicles to be parked, fueled, and maintained. Over time, the City’s truck fleet is anticipated to convert from internal combustion engines to a mixture of a variety of zero emission systems including but not limited to hydrogen, electric vehicles (EV) and possibly other platforms as they become available. Both the timeline and method for the conversion of the fleet to future uses such as hydrogen or EVs are currently unknown; however, for illustrative purposes, the site plan shows the fleet vehicle parking area as if it were developed as EV charging stations for all of the EU fleet vehicles. Preliminarily, the EV charging station would employ a pod-type approach. Each pod would enable charging four vehicles (two on each side). These pods would be deployed in a matrix to enable a pull through access to the charging stations for the entire City fleet. The method of charging the fleet would need to be developed as the trucks become available.

The EU fleet conversion from an internal combustion engine fleet to a zero emission, or reduced emission fleet is anticipated to occur in phases, where a portion of the area would be temporarily removed from service and converted to EV charging or possibly hydrogen fueling while the remainder remains in service for the fleet. Because the number of fleet trucks is estimated to increase (essentially double) in the long term, the conversion to hydrogen or EV stations would be managed within the fleet purchasing/replacement schedule.

A truck fueling facility would be located between Phillip Road and the Equipment Maintenance Facility area. This fueling area would provide fuels for all of the non-EV vehicles envisioned at the site, including gasoline, diesel, and possibly other fuels as appropriate.

The Equipment Maintenance Facility area would include the EU Shop and Repair Area, which would be designed to accommodate 24 maintenance bays sized for route trucks and one maintenance bay sized for transfer trucks. The EU Shop and Repair Area would include areas for spare parts, fluids, tires, and other routine wear items. It would be located adjacent to the fleet parking area to enable staging of trucks before and after for servicing.

A Truck/Container Wash Facility is included in the Equipment Maintenance Facility area. It would be sized to include six wash bays: four bays sized for route trucks, one bay sized for transfer trucks, and one bay sized to wash waste bins and carts.

This area would also include an EU Fleet Administrative Office and employee parking area to support workers, including managers, mechanics, and maintenance service employees using this facility. This office would also include areas for worker support functions such as restrooms, break areas, and meeting/conference rooms.

Project Description Ascent
City of Roseville
2-18 Roseville Environmental Utilities Operations Center Project Draft EIR

2.4.3 Vendor Lease Area
The project includes an area available for lease to vendors. This area would provide private haulers—who could commit to delivering recyclable, MSW, or organic waste to the RRTO—with convenient space for their fleet collection or transfer vehicles to park and be fueled and serviced, as a part of their commitment to the City’s RRTO Facility functions. Parking would be provided for 50 to 100 collection type waste fleet trucks and a similar number of employee parking spaces for drivers of the vendor collection fleet. The Vendor Lease area includes parking for vendor dispatch staff and equipment mechanics. The Vendor Lease area also includes the site’s existing buildings and residence. Although the structures could be demolished, some may be repurposed for use by prospective vendors as a part of their operational needs. For example, the existing residential structure may be repurposed as a vendor administration office. Until such time as prospective vendors are able to assess the existing structures, the area is envisioned as remaining as is and it is not included in the mass earthwork analysis discussed below.

2.4.4 Potential Future Organics Processing Facility
A potential future compost facility and/or biomass to energy facility (biomass facility) would be sized to accommodate the combined quantities of the City’s forecasted organic wastes and organic wastes from sources outside the City. However, the necessity of this function in terms of both economics and technical viability will be evaluated by the City at a later time and may be subject to supplemental CEQA review if certain conditions are met.

The potential future compost and/or biomass facility operations would be located at the northernmost portion of the project site, the farthest from Phillip Road to reduce the likelihood of the public encountering dust or air emissions.

This location, north of the RRTO Facility, would also provide the compost site the benefit of being partially screened from view by the RRTO building, providing additional separation from the public using Phillip Road (Figure 2-3).

The compost facility and/or the biomass facility (described below) could be pursued if the City’s requirements for financially attractive organic waste treatment are not satisfied by contracting for services off-site. If the off-site operators were to offer financially competitive terms, similar to what could be developed by the City at the site, the City may or may not elect to develop the compost facility and/or the biomass facility. For the purposes of this EIR analysis, the compost facility and/or the biomass facility is evaluated as part of Phase 2 and at a programmatic level.

POTENTIAL FUTURE COMPOST FACILITY
The Compost Facility would be designed to receive and process the estimated quantities of organic materials generated within the City and may include materials delivered by prospective vendors to the extent there is available capacity for these materials to be processed. The Compost Facility is where organic wastes (e.g., green waste, limbs, wood, food wastes) would be converted into a finished compost product. The facility would include materials receipt, contaminant removal, mixing, composting, curing, and final product management of the City’s organic waste.

Preliminary estimates show that the compost process would require approximately 20 to 30 acres to process the anticipated quantities of materials using an Aerated Static Pile (ASP) type of composting system. ASP type composting systems are considered a Best Available Control Technology (BACT) for reducing pollutants, as determined by several local air districts across California, such as the San Joaquin Valley Air Pollution Control District (SJVAPCD 2023).

POTENTIAL FUTURE BIOMASS FACILITY
Another potential future strategy for managing organic wastes is the development of a Biomass Facility. The Biomass Facility would be evaluated by the City on its financial, environmental, and regulatory merits and, if determined to be in the best interest of the City, would be developed at a later time. Its purpose would be to convert biomass (woody material) into energy using thermal means. The specific type of device has yet to be selected but for the purposes of this analysis, it is assumed that the biomass facility would handle organic (i.e., food and agricultural) as well as yardtrimming waste. In the event that a biomass facility is proposed at a later date, additional subsequent environmental analysis may be necessary. The potential future Biomass Facility would be co-located in the same area as the potential future Compost Facility.

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-19

2.4.5 Landscaping and Security

LANDSCAPING AND FENCING
Landscape setbacks and fencing would be provided around the perimeter of the project site as a buffer along Phillip Road and Pleasant Grove Creek. Any new landscaping would be water-efficient landscaping in compliance with the City of Roseville Water Efficient Landscape Ordinance (WELO). The existing rice and hay fields in and adjacent to the project site and owned by the City may continue to operate until the City needs those areas.

Perimeter and internal fencing is anticipated to be a six-foot-tall chain-link fence, or equivalent. Screening along portions of the chain link fence may be installed as deemed necessary. The RRTO Facility, EU Services Facility, and Equipment Maintenance Facility area would be fenced separate from one another with gates providing controlled access between each facility. The potential future Organics Processing area would also be fenced. The Vendor Lease Area would be fenced separately.

LIGHTING
Outdoor lighting for the facilities would consist of pole and/or building mounted lighting to provide appropriate illumination for night operations and safety. Lighting would employ cut-off type lights to minimize off-site light pollution and skyglow as required by City ordinance and explained in Section 3.1, “Aesthetics and Visual Resources.”

CIRCULATION AND SECURITY
The main entry to the project site would be from Phillip Road. It would include a public driveway and an internal circulation road to provide access to a surface parking lot. Sufficient parking would be provided for operational vehicles (heavy and light duty), staff, and members of the public. Security systems would include controlled access through installation of perimeter fencing, security gates, and cameras.

2.4.6 Staffing and Operational Hours
Based on the previously discussed sizing efforts, staffing levels were estimated for each of the project components (Table 2-3).

Table 2-3 Anticipated Staffing Levels
Project Component
Existing Staff to
be Relocated
Phase 1 New
Staff
Phase 2 New
Staff
Total New Staff
(Phase 1 +2)
RRTO Facility MRF 0 28 53 81
Transfer Station 0 10 3 13
Scale House 0 5 3 8
EU Services Facility Business Services and Management 11 33 0 33 Technical Services 13 30 0 30
Water Utility 61 148 0 148
Refuse and Stormwater Utility 61 138 0 138
Equipment Maintenance Facility 19 37 0 37
Vendor Lease Area 0 10 20 30
Future Potential Organics Processing Facility1 0 0 13 13 TOTAL 165 439 92 531
Notes: EU = Environmental Utilities; MRF = materials recovery facility; RRTO = Resource Recovery and Transfer Operations.

Source: Provided by HDR in 2025.

Project Description Ascent
City of Roseville
2-20 Roseville Environmental Utilities Operations Center Project Draft EIR Typical operational hours for Phase 1 would be 5 a.m. to 10 p.m., with the majority of staff working from 7 a.m. to 7 p.m. Some facilities, however, would need to operate 24 hours per day. At ultimate buildout of Phase 2, the facility would operate 24 hours per day throughout the year. Waste hauling to and from the site would generally be concentrated to the hours of 6 a.m. to 5 p.m.

2.4.7 Site Improvements

FLOODPLAIN
A portion of the project site is within a 100-year flood zone of Pleasant Grove Creek according to Federal Emergency Management Agency (FEMA) flood maps. Figure 2-6 shows the areas that FEMA has designated as Special Flood Hazard Areas (SFHAs) and the applicable risk premium zones. It was developed from FEMA’s Flood Insurance Rate Map (FIRM) of the project site, which serves as the official flood map for insurance purposes. A similar portion of the project site is also identified as being within Roseville’s Regulatory Floodplain, which is defined in the Safety Element of the City’s General Plan.

To develop this portion of the project site, a portion of the historically flooded area would need to be removed from the FEMA flood zone and Roseville’s Regulatory Floodplain. The removal of the area from the FEMA flood zone would include the preparation of a preliminary conditional Letter of Map Revision (LOMR) request to FEMA for approval. Following FEMA and City approval, grading plans and construction documents would be prepared, and FEMA would review and consider for approval the final LOMR. The City would remove the northern portion of the proposed development area from the FEMA flood zone by importing fill and raising that portion of the site.

Compensation for areas filled and removed from the floodplain is required such that there are no off-site increases to the 100-year water surface elevation or Base Flood Elevation. For the purposes of this analysis, it is assumed that this component of the project would be conducted as part of Phase 1, although a portion of this area within the 100-year floodplain (shown in Figure 2-6) is located within the potential organics processing facility that would not be operational until Phase 2.

UTILITIES
Utility service is not currently available at the project site except for limited data and electricity. Thus, the project includes the extension of nearby water, wastewater, stormwater, data, and electrical infrastructure.

Potable Water
Potable water demands are based on the estimated staffing of the facilities by phase. A 1.5 safety factor (i.e., 1.5 times more water is identified than is estimated to be required) was included to account for visitors and additional miscellaneous demands. This resulted in the following gallons per day (GPD) requirements for potable water:
 21,000 GPD potable water in 2028; and
 50,000 GPD potable water in 2040.

Additional non-potable water demands were estimated based on the anticipated building areas, with a 1.5 safety factor applied. This resulted in the following GPD requirements for non-potable water:
 24,000 GPD non-potable water in 2028; and
 56,000 GPD non-potable water in 2040.

The non-potable fire water storage water demand was determined to be 960,000 gallons based on the California Fire Code, with City of Roseville amendments, to meet the potential maximum fire flow demand for the project.

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-21 Source: Image produced and provided by HDR in 2025; adapted by Ascent in 2025.

Figure 2-6 FEMA Flood Zone

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-23 To meet the water demands and redundancy requirements of the project, a new water pipe would be extended to the site to meet both the potable and non-potable water requirements. A new 16-inch diameter water supply line would be extended approximately 3 miles along the alignment of Phillip Road, from the existing water supply line located in Blue Oaks Boulevard. The pipeline could be upsized to a maximum diameter of 24 inches to provide a water connection from the north to the Regional University Specific Plan (RUSP) area located approximately 1 mile south of the project site and/or other future development within unincorporated Placer County. In that event, the project proponent requesting to connect to the City pipeline would prepare additional CEQA documentation to determine the potential for impacts. However, this option is speculative at this time and not included in this analysis.

Fire and Life Safety
Water for fire suppression would be provided either extending the public water supply system from Blue Oaks Boulevard to the project site or using existing non-potable water wells to fill an approximately 1 million gallon fire suppression water pond or tank equipped with a diesel-powered fire suppression water pumping system that would supply the fire sprinkler system and onsite hydrants. The extension of the public water from Blue Oaks to the project site is approximately 2.3 miles to the point of connection. The fire water supply for the EU Operations Center as a whole would be sized to meet the fire department requirement of 4,000 gallons per minute.

Fire Contact Water Management
In the event of a fire, water that contacts waste is then considered contaminated and that contact water would be directed to a fire water contact pond. The fire water contact pond would be capable of receiving/holding approximately two million gallons. The fire water contact pond would be used to capture fire contact water such that the water can be tested and then eventually released to the sewer. It is assumed the fire water contact pond would be equipped with a pump to evacuate the pond over one to two weeks following the fire. The sanitary sewer discharge line would be sized to accommodate the fire water contact liquids.

Sanitary Sewer
Sanitary sewer service is required for the project for a variety of wastewater discharge needs. The primary sources of wastewater discharge would include industrial discharges from the fire water contact pond, fleet vehicles washed at the site, MSW Transfer Station and MRF floor washdown, and wastewater from the materials received at the RRTO building. Additional sources of wastewater discharge would include sewer discharges (toilets, sinks) from the buildings. Installation of pretreatment equipment would be required to appropriately treat all industrial wastewater sources to the industrial standards in Roseville Municipal Code Chapters 14.12 and 14.26; such pretreatment equipment could include but is not limited to screening, baffled trench drains, and sand-oil interceptors. Additional discharges from other sources, such as wet trash, dust suppression, vehicle wash areas, and potential excess water in the compost yard, would also be included in the project’s total discharge. Contact water from composting operations, a proposed element of Phase 2, would be evaporated on site and is not intended to be discharged to the sewer.

Sanitary sewer and wastewater flows would drain from each building area to a single, central duplex lift station, where the combined flow would be conveyed by a force main offsite to the Pleasant Grove wastewater treatment plant (WWTP). The project site is located west and lower in elevation than the WWTP. Consequently, the project site would be equipped with a pumping/lift station to pump sewerage to a point in the City’s sewer main with adequate capacity, as agreed to by the City Wastewater Utility. A number of proposed developments are anticipated to need connection to the City sewer system, including City and County developments, and there is limited space in the potential Phillip Road and Blue Oaks Boulevard sewer alignment to the WWTP approximately 4 miles east of the site.

There is potential for collaboration between these developments to share development of one or more sewer pipelines in this corridor to serve all needs with fewer impacts. Collaboration with these other projects could result in the construction of an approximately 2-mile force main for the project and sharing construction efforts on the remaining 2-mile distance. For purposes of this EIR analysis, however, the project is assumed to require construction of a force main from the project site directly to the WWTP, the entire 4-mile distance.

Wastewater discharge concentration levels were studied for biological oxygen demand (BOD) and total suspended solids (TSS) pollutant loads. At project buildout (2040), estimated dry and wet weather BOD and TSS loads in pounds per day (lb/d) are estimated to be:

Project Description Ascent
City of Roseville
2-24 Roseville Environmental Utilities Operations Center Project Draft EIR  Dry weather: 84 lb/d BOD and 106 lb/d TSS; and
 Wet weather: 262 lb/d BOD and 327 lb/d TSS.

Comparison of the estimated BOD and TSS loads with estimated Pleasant Grove WWTP capacity indicates that these loads are considered minor relative to Pleasant Grove WWTP’s capacity.

Stormwater Management
Stormwater would be managed onsite using a series of stormwater detention basins, which are shown in Figure 2-4.

Each onsite stormwater detention basin would be designed to accommodate on-site runoff generated at the site and manage it in a manner that is consistent with applicable regulations and historic discharge levels. The design would comply with the West Placer Stormwater Quality Manual.

Runoff from the potential future compost facility would be managed using a series (minimum of two) of basins.

Contact water from the compost facility would be retained, managed in accordance with regulatory requirements (e.g., WDR Order WQ-2020-0012-DWQ pertaining to composting), and reused in the composting process to the maximum extent possible.

Electricity
Electrical power to the site would be provided by Roseville Electric. The project’s total estimated power demand would be approximately 20 megawatts (MW) with an estimated utility service size of 5 megavolt amperes (MVA). The project would require an initial demand of approximately 5 MW, and then increase to the larger, 20 MW demand when the City implements the electrical charging program for its truck fleet.

Under Phase 1, the project would be served by extending the existing 12 kilovolt (kV) line from its current location near Blue Oaks Boulevard. The initial extension of power to the site for the 5 MW requirements would be provided via above grade power poles. Standby generation is anticipated to be needed for backup power to selected loads for the single 12 kV line. Generator sizes and locations would be determined during detailed design. Automatic transfer switches would be installed for control of the generators.

The total estimated power demands of the project with the added EV Fleet Charging stations would be approximately 18 MW. Estimated total buildout electrical service size with contingency capacity for planning purposes would be approximately 20 MW.

Prior to developing the EV charging system, the project would likely require development of a new substation with Roseville Electric to serve the project. To accomplish this, Roseville Electric is expected to extend an existing 60 kV line from the existing 60 kV power supply system located near the City power production site on Phillip Road east of Westbrook Boulevard and build a new substation on the project site (shown in Figure 2-4). The 60 kV line would be extended along the south side of Blue Oaks Boulevard, starting at the southeast corner of Westbrook Boulevard, turning north at Phillip Road, to a new substation on the Phillip Road project site (this portion of the alignment is included as part of the proposed Phillip Road Project and the environmental impacts of installing this portion of the alignment are evaluated in the Phillip Road Draft EIR). From the Phillip Road project site, the power line would be extended north to the western part of Phillip Road, where it would be extended along the north side of Phillip Road to the Roseville EU Center Operations project site. A 35-foot-wide public utility easement would be needed along the north side of Phillip Road. The new substation would then transform the 60 kV power down to 4,160 volt (V) or 480 V for the site. Roseville Electric estimates approximately 1 acre of land would be needed for its substation. Although a portion of the 60 kV line is planned to be installed as part of the proposed Phillip Road Project, as explained above, the full length of the 60 kV line is addressed in this EIR for completeness.

Under Phase 2, the expansion of the RRTO and the addition of the Future Potential Compost Organics Processing Facility would fit within the maximum 20 MW envisioned.

Ascent Project Description
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 2-25

PHILLIP ROAD IMPROVEMENTS
To provide access to the project site, Phillip Road would be improved from its current condition along the frontage of the project site and east to the westerly terminus of Blue Oaks Boulevard. Similar to the above discussion of utilities, other developments in the region may improve portions of this alignment ahead of this project. The improvements to Phillip Road are expected to reflect the City’s standard, 48-foot right of way Collector/Commercial street requirements, excluding sidewalks.

2.5 PROJECT CONSTRUCTION
As described above, the project would be developed in two phases, with Phase 1 intended to be operational by 2028 and Phase 2 intended to be operational by 2040, as shown in Table 2-4. The proposed phasing plan is also depicted in Figure 2-5.

Table 2-4 Project Schedule
Project Phase Project Component Construction Operation
Phase 1 Mass rough grading of the entire site, including the future RRTO expansion areas and Potential Future Organics
Processing facility area
March 2027 through October 2028 NA
RRTO Facility (Phase 1)
Vendor Lease Area
March 2027 through October 2028 October 2028
Corporation Yard
 EU Services Facility
 Equipment Maintenance Facility
Constructed on an as-needed basis As early as 2028
Phase 2 RRTO Facility Expansion (Phase 2) Constructed on an as-needed basis As early as 2040 Potential Future Organics Processing Facility Beginning in 2035 2040 Source: Provided by HDR in 2025.

Construction hours would be 7:00 a.m. to 7:00 p.m. Monday through Friday. Construction could also occur from 8:00 a.m. to 8:00 p.m. on Saturdays and Sundays on an as-needed basis. Additionally, nighttime construction would likely be required for large concrete pours, on an as-needed basis, starting as early as 11:00 p.m. and continuing through the following day. Per the City’s noise ordinance, all construction equipment would be fitted with factory installed muffling devices and all construction equipment would be maintained in good working order.

As noted above, construction would be conducted over two phases of development. A range of 40-60 construction workers would be onsite throughout construction of both Phases 1 and 2. Additionally, it is estimated that approximately 114,000 cubic yards of material would be imported to the site during construction of Phase 1.

Access during construction would be from Phillip Road. Pile driving and blasting are not anticipated. Construction would comply with the City’s tree mitigation policy if protected trees are identified in any of the construction areas.

The City and its construction contractors would adhere to standard construction-related dust control best management practices, including the following:
 Develop and implement a dust control plan.
 Use water trucks or sprinkler systems in sufficient quantities to prevent airborne dust from leaving the site.

Increased watering frequency is required whenever wind speeds exceed 15 miles-per-hour. Reclaimed (nonpotable) water will be used whenever possible and available.  Spray all dirt stockpiles daily.
 Pave all roadways, driveways, and sidewalks as soon as possible, with building pads laid as soon as possible after grading unless seeding or soil binders are used.

Project Description Ascent
City of Roseville
2-26 Roseville Environmental Utilities Operations Center Project Draft EIR

2.6 POTENTIAL PERMITS AND APPROVALS REQUIRED
As the lead agency pursuant to CEQA, the City is responsible for considering the adequacy of the EIR and determining if the project should be approved. The City will be the permitting agency for the project with regards to the tree permits, civil permits, building permits, design review, and utility connection permits to connect to the City utilities. In addition, elements of the project could be subject to permitting and/or approval authority of other agencies. Potential permits required from other agencies could include:

2.6.1 Federal
 Federal Emergency Management Agency: Conditional Letter of Map Revision.  US Army Corps of Engineers: Compliance with Section 404 of the Clean Water Act if fill would be discharged to Waters of the US.
 US Environmental Protection Agency: Concurrence with Clean Water Act Section 404 permit.  US Fish and Wildlife Service: Compliance with Section 7 of the federal Endangered Species Act for federal agency approvals if there is potential take of listed species.

2.6.2 State
 California Department of Fish and Wildlife, Region 2: Section 1602 streambed alteration agreement if any construction activities occur within the bed or bank of adjacent waterways.  California Department of Resources Recycling and Recovery: Solid waste facility permit.  State Water Resources Control Board and Central Valley Regional Water Quality Control Board: National Pollutant Discharge Elimination System (NPDES) permits:
 Construction stormwater permit (Notice of Intent to proceed under Construction General Permit) for disturbance of more than 1 acre,
 Industrial stormwater permit (Notice of Intent to operate under the Industrial General Permit), and  As applicable, compliance with the Clean Water Act Section 401 water quality certification and/or waste discharge requirements.

2.6.3 Local
 Placer County: Integrated Waste Management Plan
 To comply with the Non-Disposal Facility Element, the facility must be added to the County’s Integrated Waste Management Plan to confirm it is not a disposal facility.  Placer County Air Pollution Control District: Authority to Construct/Permit to Operate, and Air Quality Management Plan consistency determination.

City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3-1 3 ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES

APPROACH TO THE ENVIRONMENTAL ANALYSIS
This draft environmental impact report (Draft EIR) evaluates and discloses the environmental impacts associated with the Roseville Environmental Utilities Operations Center Project, in accordance with the California Environmental Quality Act (CEQA) (Public Resources Code [PRC] Section 21000, et seq.) and the State CEQA Guidelines (California Code of Regulation, Title 14, Chapter 3, Section 15000, et seq.). As explained previously and throughout this EIR, Phase 1 of the Roseville Environmental Utilities Operations Center Project is evaluated at a project level. Phase 2 includes two primary components: expansion of Phase 1 project facilities, which is evaluated at a project level, and the addition of a potential future organics processing facility, which is evaluated at a program level.

Sections 3.1 through 3.17 of this Draft EIR present a discussion of regulatory background, environmental setting, environmental impacts associated with construction and operation of the project, mitigation measures to reduce the level of impact, and residual level of significance (i.e., after implementation of mitigation, including impacts that would remain significant and unavoidable after implementation of feasible mitigation measures). Issues evaluated in these sections consist of the environmental topics identified for review in the notice of preparation (NOP) prepared for the project (see Appendix A).

Chapter 4 of this Draft EIR, “Cumulative Impacts,” presents an analysis of the project’s impacts considered together with other past, present, and probable future projects producing related impacts, as required by Section 15130 of the State CEQA Guidelines. Chapter 5, “Other CEQA Sections,” includes an analysis of the project’s growth inducing impacts, as required by Sections 21100(b)(5) and 15126.6(e) of CEQA. Chapter 6, “Alternatives,” presents a reasonable range of alternatives and evaluates the environmental effects of those alternatives compared to the proposed project, as required by Section 15126.6 of the State CEQA Guidelines.

Sections 3.1 through 3.17 of this Draft EIR each include the following components.

Regulatory Setting: This subsection presents information on the laws, regulations, plans, and policies that relate to the issue area being discussed. Federal, state, and local laws, regulations, plans and policies that are applicable to the project are discussed as appropriate.

Environmental Setting: This subsection presents the existing environmental conditions on the project site and in the surrounding area as appropriate, in accordance with State CEQA Guidelines Section 15125. The discussions of the environmental setting focus on information relevant to the issue under evaluation. The extent of the environmental setting area evaluated (the project study area) differs among resources, depending on the locations where impacts would be expected. For example, air quality impacts are assessed for the air basin (macroscale) as well as the site vicinity (microscale), whereas transportation and circulation impacts are assessed for the project site vicinity.

Environmental Impacts and Mitigation Measures: This subsection presents thresholds of significance and discusses potentially significant effects of the Roseville Environmental Utilities Operations Center Project on the existing environment, including the environment beyond the project boundaries, in accordance with State CEQA Guidelines Section 15126.2. The methodology for impact analysis is described, including technical studies upon which the analyses rely. The thresholds of significance are defined and thresholds for which the project would have no impact are disclosed and dismissed from further evaluation. Project impacts and mitigation measures are numbered sequentially in each subsection (Impact 3.1-1, Impact 3.1-2, Impact 3.1-3, etc.). A summary impact statement precedes a more detailed discussion of the environmental impact. The discussion includes the analysis, rationale, and substantial evidence upon which conclusions are drawn. The determination of level of significance of the impact is defined in bold text. Impact summaries and mitigation measures are provided separately for Phases 1 and 2 of the Roseville Environmental Utilities Operations Center Project, where applicable.

A “less-than-significant” impact is one that would not result in a substantial adverse change in the physical environment. A “potentially significant” impact or “significant” impact is one that would result in a substantial adverse

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3-2 Roseville Environmental Utilities Operations Center Project Draft EIR change in the physical environment; and both are treated the same under CEQA in terms of procedural requirements and the need to identify feasible mitigation. Mitigation measures are identified, as feasible, to avoid, minimize, rectify, reduce, or compensate for significant or potentially significant impacts, in accordance with the State CEQA Guidelines Section 15126.4. Unless otherwise noted, the mitigation measures presented are recommended in the EIR for consideration by the City to adopt and incorporate into the project.

Where an existing law, regulation, or permit specifies mandatory and prescriptive actions about how to fulfill the regulatory requirement as part of the project definition, leaving little discretion in its implementation, and would avoid an impact or maintain it at a less-than-significant level, the environmental protection afforded by the regulation is considered before determining the significance of the impact. Where existing laws or regulations specify a permit process for future projects, performance standards without prescriptive actions to accomplish them, or other requirements that allow substantial discretion in how they are accomplished, or have a substantial compensatory component, the level of significance is determined before applying the influence of the regulatory requirements. In this circumstance, the impact would be potentially significant or significant, and the regulatory requirements would be included as a mitigation measure.

This subsection also describes whether mitigation measures would reduce project impacts to less-than-significant levels. Significant and unavoidable impacts are identified as appropriate in accordance with State CEQA Guidelines Section 15126.2(b). Significant and unavoidable impacts are also summarized in Chapter 5, “Other CEQA Sections.” References: The full references associated with the parenthetical references found throughout Sections 3.1 through

3.17 can be found in Chapter 8, “References,” organized by section number.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-1

3.1 AESTHETICS AND VISUAL RESOURCES
This section describes the existing visual conditions, meaning the physical features that make up the visible landscape, near the project site and evaluates the potential changes to those conditions that would occur due to project implementation. The effects of the project on the visual environment are generally defined in terms of the project’s physical characteristics and potential visibility, the extent to which the project’s presence would change the perceived visual character and quality of the environment, and the expected level of sensitivity that the viewing public may have where the project would alter existing views.

No comment letters regarding aesthetics were received in response to the notice of preparation (see Appendix A).

3.1.1 Regulatory Setting

FEDERAL
No federal plans, policies, regulations, or laws related to aesthetics are applicable to the project.

STATE
California Energy Code and Green Building Regulations
The California Energy Code and Green Building Regulations (CALGreen) require that all luminaires1 must meet the mandated BUG (Backlight/Uplight/Glare) ratings according to their designated lighting zone unless otherwise exempt; lighting for sports and athletic fields is exempt. All outdoor luminaires that emit 6,200 lumens or greater must comply with BUG requirements contained in Section 5.106.8 of the CALGreen Code (Title 24, Part 11).

The BUG ratings assume that the light emitted from the luminaire is providing useful illuminance on the task surfaces rather than scattering the light in areas where the light is not needed or intended, such as toward the sky. The BUG ratings also increase visibility because high amounts of light shining directly into observer’s eyes are reduced, thus decreasing glare. Additionally, light pollution into neighbors’ properties is reduced. The BUG requirements vary by outdoor lighting zones.

California Scenic Highway Program
California’s Scenic Highway Program was created by the California Legislature in 1963 and is managed by the California Department of Transportation (Caltrans). The goal of this program is to preserve and protect scenic highway corridors from changes that would affect the aesthetic value of the land adjacent to highways. A highway may be designated “scenic” depending on how much of the natural landscape travelers can see, the scenic quality of the landscape, and the extent to which development intrudes on travelers’ enjoyment of the view. The nearest eligible highway is State Route (SR) 49, located approximately 20 miles northeast of the project site, and the nearest designated highway is SR 160, located approximately 23 miles south of the project site (Caltrans 2025).

Nighttime Sky – Title 24 Outdoor Lighting Standards
The Nighttime Sky- Title 24 Outdoor Lighting Standards were created in 2005 by the California Energy Commission to regulate energy efficiency of all outdoor lighting for residential and nonresidential development. The standards reduce the adverse effects of outdoor lighting and improve overall quality by providing guidance for lighting characteristics such as maximum power and brightness, shielding, and sensor controls to turn lighting on and off. 1 A luminaire is a complete lighting unit, comprised of light source (lamp or lamps), together with the parts that distribute the light, position and protect the lamps, and connect the lamps to the power supply.

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3.1-2 Roseville Environmental Utilities Operations Center Project Draft EIR LOCAL
City of Roseville General Plan
The City of Roseville 2035 General Plan (City of Roseville 2020) includes the following relevant policies that pertain to aesthetic resources:

Community Form: General
 Policy LU1.1: Ensure high-quality development in new and existing development areas, as defined through specific plans, the development review process, and the Community Design Guidelines.

Community Design
 Policy LU7.1: Through the design review process, apply design standards that promote the use of high quality building materials, architectural and site designs, landscaping signage, and amenities.  Policy LU7.2: Continue to develop and apply design standards that result in efficient site and building designs, pedestrian friendly projects that stimulate the use of alternative modes of transportation, and the establishment of a functional relationship between adjacent developments.  Policy LU7.3: Encourage designs that strike a balance between the incorporation of aesthetic and development requirements, and the economic considerations associated with development.  Policy LU7.4: Promote flexibility in the design review process to achieve design objectives, and encourage projects with innovative, unique and creative architectural style and design.  Policy LU7.6: Encourage project designs that place a high priority and value on open space, and the preservation, enhancement and incorporation of natural resources and other features including consideration of topography, vegetation, wetlands, and water courses.
 Policy LU7.8: The location and preservation of native oak trees and oak woodlands shall be a primary factor in determining site design, building location, grading, construction and landscaping, and in establishing the character of projects through their use as a unifying element in both new and existing development.  Policy LU7.9: Control artificial lighting to avoid spill-over lighting onto adjacent properties. Use anti-reflective architectural materials and coatings to prevent glare.

Growth Management – New Growth Areas
 Policy LU9.9: Development proposed on the western edge of the City shall provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained.

Community Design Guidelines
Community Design Guidelines for the City of Roseville were adopted in 1995 to create consistency in the quality of new development. The Community Design Guidelines promote design principles that encourage diversity, balance aesthetic and functional considerations, and attempt to integrate the natural and built environments. The Design Committee, Planning Commission, and City Council use the Community Design Guidelines in the design review process for projects requiring discretionary approval, and by City staff for discretionary projects that are approved by the Planning Manager (City of Roseville 2008). The Community Design Guidelines address the following topics:
 site planning and architectural design standards for new residential, commercial, and industrial development and modifications to existing buildings;
 landscaping and screening techniques to preserve and enhance the visual quality;  signs for new development;
 landscaping and signage at entryways;
 streetscape improvements such as street trees, landscaped medians, and street furnishings; and

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-3  lighting design and provisions to promote public safety and reduce glare and light spillover onto adjacent properties.

City of Roseville Water Efficient Landscape Ordinance
The purpose of the Water Efficient Landscape Ordinance is to comply with the Water Conservation in Landscaping Act of 2006 and to define the standards and procedures for the design, installation, and management of landscaping. It is intended to utilize available plant, water, land and human resources to the greatest benefit of Roseville residents.

Consistent with the legislative findings and purpose of the Ordinance, conditions in the urban setting will be improved by:

1. Creating the conditions to support life in the soil by reducing compaction, incorporating organic matter that increases water retention, and promoting productive plant growth that leads to more carbon storage, oxygen production, shade, habitat and aesthetic benefits.

2. Minimizing energy use by reducing irrigation water requirements, reducing reliance on petroleum-based fertilizers and pesticides, and planting climate appropriate shade trees in urban areas.

3. Conserving water by capturing and reusing rainwater and graywater wherever possible and selecting climate appropriate plants that need minimal supplemental water after establishment.

4. Protecting air and water quality by reducing power equipment use and landfill disposal trips, selecting recycled and locally sourced materials, and using compost, mulch and efficient irrigation equipment to prevent erosion.

5. Protecting existing habitat and creating new habitat by choosing local native plants, climate adapted non-natives and avoiding invasive plants. Utilizing integrated pest management with least toxic methods as the first course of action.

3.1.2 Environmental Setting

METHODOLOGY AND TERMINOLOGY
Identifying the project area’s visual resources, character, and quality involves the following process:
 objectively identify visual features and resources of the landscape,  assess the character and quality of the resources relative to overall regional visual character, and  determine importance to people (or sensitivity) of views of visual resources in the landscape.

Visual quality is assessed through determining the degree of vividness, unity, and intactness of the view:
 Vividness: The extent to which the landscape is memorable, which is associated with the distinctiveness, diversity, and contrast of visual elements.
 Intactness: The integrity of visual order in the landscape and the extent to which the existing landscape is free from atypical visual intrusions (i.e., an element that appears out of place with the visual order).  Unity: The extent to which visual intrusions are sensitive to and in visual harmony with the existing landscape.

REGIONAL SETTING
The northwest portion of the City of Roseville is generally regarded as a transitional zone between the flat, open terrain of the Central Valley to the west and the foothills of the Sierra Nevada Mountains to the east. Long-range views within the region include views of the Sierra Nevada, Sutter Buttes, and the Coast Range.

The project site is located on 243 acres along Phillip Road, near its western terminus at South Brewer Road, at the northwest limit line of the City of Roseville in Placer County. The project site is owned by the City, and is predominantly agricultural in use and is leased for rice and hay farming. The planned Pleasant Grove Stormwater Retention Basin Facility would be located to the east of the site, Reason Farms Preserve is located to the northeast of

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3.1-4 Roseville Environmental Utilities Operations Center Project Draft EIR the site, Pleasant Grove Creek is located along the site’s northern boundary, several rural residences are located south of the site, and three specific plan areas (the Creekview Specific Plan, the West Roseville Specific Plan, and the Amoruso Ranch Specific Plan) are each located near or within a two-mile radius. The Regional University Specific Plan area is located in the vicinity of the project site and is approved but not constructed yet. Accordingly, the Regional University Specific Plan area is not included in the existing visual setting. The visual setting and quality of these landscapes are described below and summarized in Table 3.1-1.

Table 3.1-1 Regional Visual Quality
Site Name Vividness Intactness Unity
Agricultural land Low to moderate Moderate to high Moderate to high Planned Pleasant Grove Stormwater Retention Basin Facility and Reason Farms Preserve High Moderate to high Moderate to high
Pleasant Grove Creek High Moderate to high Moderate to high Creekview Specific Plan area Low to moderate Low to moderate Moderate to high West Roseville Specific Plan area Low to moderate Low to moderate Moderate to high Amoruso Ranch Specific Plan Low to moderate Low to moderate Moderate to high Source: Compiled by Ascent in 2025.

The surrounding agricultural land consists of row crops, grain crops, and grassland that support livestock grazing (City of Roseville 2020). Lands immediately west and south of the project site are in active agriculture production. The visual intactness and unity of the agricultural lands are both moderate to high due to the visual integrity and connectivity of the agricultural parcels. With the exception of roadways, the agricultural land west and south of the project site is generally undisturbed by other land uses, although the Country Acres Solar Project is under construction south of the project site. The vividness of the agricultural lands is low to moderate due to the lack of striking and distinctive visual patterns in the landscape. The view within these agricultural lands is generally flat in topography and visually consistent with row crops, orchards, and grasslands, and no major landmarks or other visual features create a striking change in the landscape.

The City’s future Pleasant Grove Stormwater Retention Basin (PGSRB) Facility would be located to the east of the site and Reason Farms Preserve is located to the northeast of the site. This nature preserve was previously used for agriculture and consists of leveled agricultural fields separated by earthen berms, many of which are also used as access roads for City staff. A gated entryway to the PGSRB site and nature preserve is marked with a rock sign, but the site is currently inaccessible to the public. Views within the area have a moderate to high visual intactness and unity. The fields within the PGSRB site are contiguous with the surrounding agricultural land creating visual unity in the landscape as a whole. Furthermore, the amount of human-caused visual disturbances within the PGSRB site and preserve are minimal, which contributes to the moderate to high visual intactness of the area. With the exception of the built road that bisects the PGSRB site and preserve and the sign at the entrance, no other major visual disturbances are present. The vividness of the PGSRB site and preserve is high due to the variation in landscape from grassland to riparian along Pleasant Grove Creek. The change in habitat is marked by a change in vegetation, with scattered oaks comprising the main vegetation type within the grassland area which transitions into a variety of riparian plant species including willow at Pleasant Grove Creek. The habitat variation is a distinctive visual pattern that adds to the high vividness of the preserve.

Pleasant Grove Creek, a third order perennial stream, is located along the site’s northern boundary. The visual intactness and unity of Pleasant Grove Creek are moderate to high due to the stream creating visual unity with the surrounding area, including the preserve and agricultural lands. The vividness of Pleasant Grove Creek is high due to the variation in landscape from riparian along the creek’s north and south banks and to grassland within the agricultural lands and surrounding area. The change in habitat is marked by a change in vegetation, with a transition from the riparian plant species at the creek, to scattered oaks within the surrounding grassland areas. The habitat variation is a distinctive visual pattern that adds to the high vividness of the creek.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-5 The Creekview Specific Plan area to the east of the project site currently consists of rolling grasslands and riparian vegetation along the Pleasant Grove Creek corridor. Housing is currently being constructed in the northern portion of the Creekview Specific Plan area. The West Roseville Specific Plan area to the southeast of the project site is a residential community with a mix of support and employment uses. A mixed-use village center is located in the center of the plan area, as well as the Regional Sports Park. The plan area visually defines the southwestern edge of the City with an open space buffer that creates a visual transition between urban uses and uses in unincorporated Placer County. The overall design intent of the plan area is to highlight the recreational amenities provided and the historic land uses with architecture that incorporates traditional styles unique to the early history of the California region (City of Roseville 2004). The visual vividness of the Creekview and West Roseville Specific Plan areas are low to moderate. The number of striking or distinctive visual patterns in the landscape is generally low due to the visual similarity of new development; the visual memorability to the landscape is also low for this reason. The visual intactness of the Creekview and West Roseville Specific Plan areas is also low to moderate. Both plan areas exist in transition zones at the City’s urban border; therefore, the visual integrity of the human-built landscape is interrupted by the agricultural lands directly to the west. The visual unity of both plan areas is moderate to high, and it should be noted that design guidelines have been and will continue to be implemented during development of these areas to ensure visual coherence and compositional harmony of the landscape considered as a whole. At buildout, the Creekview Specific Plan area will include 2,011 single and multi-family residential units, approximately 136 acres of open space, 15.7 acres of neighborhood parks, a 7-acre school site, 2.6 acres of utilities sites, and 19.3 acres for commercial development (City of Roseville 2021). The West Roseville Specific Plan area is built out.

The Amoruso Ranch Specific Plan area to the northeast of the project site consists of rolling terrain generally trending west and south. The majority of the Amoruso Ranch Specific Plan area is characterized by wide expanses of flat to rolling grasslands, which are currently being developed with housing and mixed uses. Minor drainages flow in a radial pattern from a slight rise in the northeast quadrant of the property. The vividness of the Amoruso Ranch Specific Plan area is low to moderate because the change in topography characterized by the rolling grasslands creates a distinct visual pattern; however, the area is currently being developed with housing and mixed uses. The number of striking or distinctive visual patterns in the landscape is generally low due the visual similarity of new development; the visual memorability to the landscape is also low for this reason. The visual intactness of the Amoruso Ranch Specific Plan area is also low to moderate. The plan area exists in a transition zone at the City’s urban border; therefore, the visual integrity of the human-built landscape is interrupted by the surrounding agricultural lands. The visual unity of the plan area is moderate to high and it should be noted that design guidelines have been and will continue to be implemented during development of this area to ensure visual coherence and compositional harmony of the landscape considered as a whole. At buildout, the Amoruso Ranch Specific Plan area will result in the development of a mix of uses, including 337 acres of low, medium, and high-density residential land developed with 2,827 dwelling units. The land use plan also includes three commercial parcels totaling 51 acres, a 9.6-acre elementary school site, seven neighborhood parks, and a 3-acre fire station/public facilities site. Approximately 135 acres of the site will be set aside as open space preserve (City of Roseville 2016).

LOCAL SETTING
Visual Character and Quality of the Project Site
Long-range views within the project site include portions of the Sierra Nevada to the east, and the Coast Range to the west. The project site is composed of undeveloped agricultural land in the northwest limit line of the City of Roseville. The land is predominantly flat with some sparsely vegetated, low hills. Annual grasslands, including remnant cultivated grain species and sparse, ruderal, nonnative plant species, cover the majority of the project site. Due to the annual species present on the project site, the views transition from green grasslands in the winter and spring to dry, golden-colored grasslands in the summer and fall. Views of the site also change throughout the year depending on seasonal agricultural activities (e.g., flooded fields for rice farming, harvested fields, fallow fields). Pleasant Grove Creek traverses along the northern property boundary in an east–west direction. Valley oak riparian woodland habitat is present along the creek channels, creating a visually prominent landmark during the summer months, when the dark foliage of the oak trees contrasts starkly with the golden-colored grassland. The only structures within the

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3.1-6 Roseville Environmental Utilities Operations Center Project Draft EIR project site include remnants from a former pheasant club, agricultural support structures, and a former residence, located in the center of the project site.

The visual vividness of the landscape within the project site is moderate. While the majority of the project site is covered in annual grassland that is contiguous with close-by agricultural parcels, several unique visual patterns are present, including the vegetation transitions marked by Pleasant Grove Creek and the human-made flood channel.

Given the annual nature of the grasslands, the landscape transitions into golden-covered fields in the summer and fall, but the vegetation associated with the creek and flood channel remains green, creating a distinctive change in the landscape. Pleasant Grove Creek combined with the annual grassland landscape creates striking visual patterns which add to the moderate visual vividness of the project site. The visual intactness and unity of the project site are also moderate. The rural, undeveloped landscape is generally free of encroaching human-made elements, as the only structures present are the remnants of a former pheasant club, agricultural support buildings, and former residence. The visual integrity and compositional harmony of the site is moderate due to the transitioning habitat types of the creek.

The overall visual character of the project site is moderate based on the moderate vividness, intactness, and unity.

Viewer Sensitivity
Viewer sensitivity is a measure of public expectation or concern for changes to scenic quality. Numbers of viewers, viewer activity, view duration, distance from seen objects (i.e., foreground versus background), and special planning designations such as scenic routes are used to characterize viewer sensitivity.

Sensitive viewers are people located near the project site who may be affected by visual changes caused by the project. Sensitive viewers are described in terms of exposure to the project and level of sensitivity. Viewer exposure takes into account viewer location, the number of viewers, and duration and frequency of views.

Table 3.1-2 lists viewer groups that would be exposed to the project’s visual changes; defines their geographic proximity to the project; qualitatively estimates the volume of viewers, duration of views, and frequency of views; and identifies the viewer sensitivity of each general viewer group. Visual sensitivity associated with views in a particular area is the combination of viewer sensitivity and viewer exposure.

Table 3.1-2 Sensitive Viewer Groups Near the Project Site Viewer
Group
Viewer Exposure Viewer
Area Sensitivity Usage Volume Duration of Views Frequency of Views Residents
To the south and west of the project site within
surrounding agricultural lands and to the east within
the Creekview and West Roseville Specific Plan areas
High High High High
Motorists Using roads adjacent to the project site primarily Phillip Road Moderate Moderate Moderate Moderate
Source: Compiled by Ascent in 2025.

SCENIC ROADWAY
A scenic road is defined as a highway, road, drive, or street that provides opportunities for the enjoyment of natural and human-made scenic resources, in addition to its transportation function. Scenic roads direct views to areas of exceptional beauty, natural resources or landmarks, or historic or cultural interest. There are no officially designated state scenic highways, or eligible state scenic highways, located in the vicinity of the project site or the greater City of Roseville. The nearest eligible highway is SR 49, located approximately 20 miles northeast of the project site, and the nearest designated highway is SR 160, located approximately 23 miles south of the project site (Caltrans 2025).

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-7

SCENIC VISTA
Scenic vistas are generally considered to be locations from which the public can experience unique and exemplary high-quality views, including panoramic views of great breadth and depth, often from elevated vantage points. No designated scenic vistas are present in the project area or the greater City of Roseville (City of Roseville 2020).

NIGHTTIME LIGHT AND DAYTIME GLARE
While the project site contains some limited structures that may produce some glare from the sunlight reflecting off building materials, the project site does not contain any substantial sources of light or glare. Sources of nighttime light around the project site are minimal. Nearby residences, located west and south of the project site, and residential neighborhoods associated with the Creekview Specific Plan area and West Roseville Specific Plan area create some nighttime light that can be seen from the project site. Occasional glare occurs from vehicles accessing roads adjacent to the project site.

SHADOWS
The evaluation of shading and shadows in this Draft EIR is limited to daytime shadows cast by objects blocking sunlight.

The angle of the sun, and hence the character of shadows, varies depending on the time of year and the time of day; however, in the Northern Hemisphere, the sun always arcs across the southern portion of the sky. During the winter, the sun is lower in the southern sky, casting longer shadows compared to other times of year. During the summer months, the sun is higher in the southern sky, resulting in shorter shadows. During the summer, the sun can be almost directly overhead at midday, resulting in almost no shadow being cast. During all seasons, as the sun rises in the east in the morning, shadows are cast to the west; at mid-day, the sun is at its highest point and shadows are their shortest, and cast to the north; and as the sun sets in the west in the afternoon/evening, shadows are cast to the east.

The only structures located on project site that create shadows are the remnants of the former pheasant club, agricultural support structures, and a former residence. The trees surrounding Pleasant Grove Creek provide shade to the creek and shadows on the project site.

3.1.3 Environmental Impacts and Mitigation Measures

METHODOLOGY
Assessment of impacts to aesthetics and visual resources is based on an objective evaluation of the proposed project's effects on the visual environment of the site and its surroundings. This includes consistency with local ordinances and policies adopted for visual integrity of the community, impacts on viewsheds and scenic areas identified as important or valuable to the community, and changes in visual character of the site as compared to existing conditions.

This visual impact analysis is based on field observations, a review of site plans and aerial photographs, photographs of the project site, the anticipated visual changes on the project site due to implementation of the project, and documents pertaining to the project site, including the City of Roseville General Plan and Community Design Guidelines. In determining the level of significance, this analysis assumes that the project would comply with relevant state and local ordinances and regulations, as well as the General Plan policies presented above.

Representative Viewpoint Descriptions
The following is a description of viewpoints that provide representative views of the project site from nearby locations. The selected views include those typically seen by the public, as well as those from residential (or future residential) areas that would be seen most frequently by the residents in the area. The location of the viewpoints is shown in Figure 3.1-1, and photographs from these viewpoints are provided in Figures 3.1-2 through 3.1-6.

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3.1-8 Roseville Environmental Utilities Operations Center Project Draft EIR Viewpoint 1
Viewpoint 1 is taken from Phillip Road, which is located along the southern boundary of the project site, and is facing east, as shown in Figure 3.1-2. Vividness from Viewpoint 1 is low. The landscape is largely composed of flat grassland with a metal fence and Phillip Road in the foreground and some sparsely arranged trees along Phillip Road and utility lines in the background. The memorability and visual power of the landscape is low due to the lack of striking and distinctive visual patterns. Intactness from Viewpoint 1 is moderate. The visual integrity of the landscape is fairly high due to the general lack of human-built elements. The grassland landscape is largely undisturbed with the exception of the human-built elements (fence, road, and utility lines) in the foreground and background. The unity is also moderate because of the visual coherence and compositional harmony of the landscape, which is similar to other agricultural and undeveloped portions of the City of Roseville. Overall, the visual quality is moderately low. The visual character is a fairly unremarkable grassland, with little variation in the topography and other visual aspects.

Viewpoint 2
Viewpoint 2 is taken from Phillip Road, similar to Viewpoint 1, and is facing west, as shown in Figure 3.1-3. Vividness from Viewpoint 2 is low. The landscape is largely composed of flat grassland with a metal fence and Phillip Road in the foreground and some sparsely arranged trees and utility lines in the background. The memorability and visual power of the landscape is low due to the lack of striking and distinctive visual patterns. Intactness from Viewpoint 2 is moderate. The visual integrity of the landscape is fairly high due to the general lack of human-built elements. The grassland landscape is largely undisturbed with the exception of the human-built elements (fence, road, and utility lines) in the foreground and background. The unity is also moderate because of the visual coherence and compositional harmony of the landscape, which is similar to other agricultural and undeveloped portions of the City of Roseville. Overall, the visual quality is moderately low. The visual character is a fairly unremarkable grassland, with little variation in the topography and other visual aspects.

Viewpoint 3
Viewpoint 3 is taken from within the project site, along the eastern edge the site facing northwest, as shown in Figure

3.1-4. Vividness from Viewpoint 3 is low to moderate. The landscape is largely composed of flat grassland; however, in the background is an array of trees associated with Pleasant Grove Creek along the northern project boundary. The number and variation of trees in the background of the viewpoint, as well as the few trees in the foreground of the viewpoint, increase the memorability of landscape. The intactness of Viewpoint 3 is high. While there is a human-built element (a well) visible in the background, the landscape is largely free from encroaching elements. The unity of Viewpoint 3 is moderate. The visual coherence and composition of the landscape considered as a whole is similar to other agricultural and undeveloped portions within the city. Overall, the visual quality is moderate. The visual character is a fairly unremarkable grassland, with little variation in the topography and other visual aspects; however, the presence of trees associated with Pleasant Grove Creek which comprises a larger portion of the viewshed in comparison to the other viewpoints increases the visual quality to some extent.

Viewpoint 4
Viewpoint 4 is taken along the northwestern boundary of the project site, facing southeast, as shown in Figure 3.1-5.

Vividness from Viewpoint 4 is low. The landscape is composed of flat grassland, with trees in the background that surround the banks of Pleasant Grove Creek and the existing structures in the center of the project site. The lack of striking and distinctive features, such as changes in topography or vegetation type, make the memorability and visual power of the landscape low. Intactness in Viewpoint 4 is high. The visual integrity of the landscape is high due to the lack of human-built elements. The grassland landscape is largely undisturbed. The unity is also moderate because of the visual coherence and compositional harmony of the landscape, which is similar to other agricultural and undeveloped portions of the City of Roseville. Overall, the visual quality is moderately low. The visual character is a fairly unremarkable grassland, with little variation in the topography and other visual aspects.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-9 Source: Adapted by Ascent in 2025.

Figure 3.1-1 Overview of Viewpoint Locations

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3.1-10 Roseville Environmental Utilities Operations Center Project Draft EIR Source: Adapted by Ascent in 2025.

Figure 3.1-2 Viewpoint 1 from Phillip Road Looking East Source: Adapted by Ascent in 2025.

Figure 3.1-3 Viewpoint 2 from Phillip Road Looking West

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-11 Source: Adapted by Ascent in 2025.

Figure 3.1-4 Viewpoint 3 from the Eastern Edge of the Project Site Looking Northwest Source: Adapted by Ascent in 2025.

Figure 3.1-5 Viewpoint 4 from the Northwestern Area of the Project Site Looking Southeast

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3.1-12 Roseville Environmental Utilities Operations Center Project Draft EIR Source: Adapted by Ascent in 2025.

Figure 3.1-6 Viewpoint 5 from the Southwestern Area of the Project Site Looking Northeast Viewpoint 5
Viewpoint 5 is taken from the southwestern boundary of the project site facing northeast, as shown in Figure 3.1-6.

Vividness from Viewpoint 5 is low. The landscape is largely composed of flat grassland with Phillip Road in the foreground and some utility lines and arrays of trees in the background. The memorability and visual power of the landscape is low due to the lack of striking and distinctive visual patterns. Intactness from Viewpoint 5 is moderate.

The visual integrity of the landscape is fairly high due to the general lack of human-built elements. The grassland landscape is largely undisturbed with the exception of the human-built elements (road and utility lines) in the foreground and background. The unity is also moderate because of the visual coherence and compositional harmony of the landscape, which is similar to other agricultural and undeveloped portions of the City of Roseville. Overall, the visual quality is moderately low. The visual character is fairly unremarkable grassland, with little variation in the topography and other visual aspects.

THRESHOLDS OF SIGNIFICANCE
Thresholds of significance are based on Appendix G of the State CEQA Guidelines. The project would cause a significant impact related to aesthetics if it would:
 have a substantial adverse effect on a scenic vista;
 substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway;
 in non-urbanized areas, substantially degrade the existing visual character or quality of public views of the site and its surroundings and in urbanized areas conflict with applicable zoning and other regulations governing scenic quality; or
 create a new source of substantial light or glare which would adversely affect day or nighttime views in the area.

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City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-13

ISSUES NOT DISCUSSED FURTHER
Views of the project site and surrounding area are dominated by farmland and undeveloped grazing land. There are no scenic vistas within the project site or visible from the project site. Further, as discussed above, the City has not identified or designated scenic vistas within the City. Therefore, the proposed development of the site would not adversely affect a scenic vista, and this issue is not discussed further.

No designated or eligible state scenic highways are in the vicinity of the project site, and the project site is not visible from any officially designated or eligible state or locally designated scenic highway. Further, the City of Roseville does not have any locally designated scenic highways. Thus, there would be no impact, and this issue is not discussed further.

The project site is not in an urban area of Roseville. Further, the City does not have zoning or other regulations that govern scenic quality. Therefore, the project would not conflict with applicable zoning and other regulations governing scenic quality, and this issue is not discussed further. The project’s consistency with applicable land use plans and policies is evaluated in Section 3.2, “Land Use Planning and Agricultural Resources.”

ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES
Impact 3.1-1: Substantially Degrade the Existing Visual Character or Quality of the Site or its Surroundings
Phase 1
Development of Phase 1 would convert approximately 116 acres of predominantly agricultural land owned by the City into municipal uses, including a Resource Recovery and Transfer Operations (RRTO) Facility, EU Operations Facility Corporation Yard (Corporation Yard), and the Vendor Lease Area. The introduction of municipal uses and infrastructure in an area that is predominantly agricultural would change the existing character of the area. However, the proposed facilities would be designed to be visually consistent and would be required to comply with General Plan policies related to community design and the City’s Community Design Guidelines. Nonetheless, the project would introduce waste and recycling collection trucks to the area, which occasionally contribute to litter. This could create a visual nuisance and could degrade the visual character of the project area. For these reasons, this impact would be potentially significant.

The project site, which is owned by the City, is predominantly agricultural in use and is leased for rice and hay farming. The land is predominantly flat with some sparsely vegetated, low hills. Annual grasslands cover the majority of the project site. Pleasant Grove Creek runs along the northern boundary of the project site and flows in an eastwest direction. Valley oak riparian woodland habitat is present along the creek channels. The only structures within the project site are remnants from a former pheasant club, agricultural support structures, and a former residence.

Development of the project site would change the existing visual character of the area both temporarily during construction and permanently during operation of the proposed EU Operations Center. These impacts are discussed below.

Construction
Construction activities would reduce the vividness, unity, and intactness of the project site’s existing visual character by introducing encroaching human elements into the natural landscape. Construction equipment and materials would be present in the project area and visible to sensitive viewer groups, including motorists and residents. The type and quantity of equipment would fluctuate throughout construction but would generally include earthmoving equipment; concrete mix trucks and concrete pumps; a crane for erection of panels; semi-trucks and other trucks for deliveries; and a variety of crew trucks, excavators, boom lifts, scissor lifts, trenchers, generators, and personal autos. Building materials and equipment would be staged in various locations on the project site throughout the duration of construction and would vary as Phase 1 is constructed. While construction activities would reduce the vividness, unity, and intactness of the project site’s existing visual character, visual impacts from construction would be temporary and limited to the construction period. As described in Chapter 2, “Project Description,” construction of the RRTO Facility and Vendor

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3.1-14 Roseville Environmental Utilities Operations Center Project Draft EIR Lease Area is intended to begin spring 2027 and end late fall 2028, with Phase 1 becoming operational by 2028. The Corporation Yard would be constructed on an as-needed basis but would become operational as early as 2028.

The project site is also within the vicinity of three specific plan areas with ongoing and future plans for development: the Creekview Specific Plan, the West Roseville Specific Plan, and the Amoruso Ranch Specific Plan, all located near or within a two-mile radius of the project site. Construction activities and their associated visual impacts within the project vicinity are common due to the surrounding development; therefore, the addition of the visual impacts associated with the project would be limited to the sensitive viewer groups who experience ongoing development in the vicinity.

Given that the visual impact from construction would be temporary and that construction is occurring in the vicinity of the project (and is therefore part of the visual landscape), Phase 1 would not substantially degrade the visual character of the area during construction. This impact would be less than significant.

Operation
The project site is primarily surrounded by undeveloped land, with the PGSRB site and the Reason Farms Preserve located to the northeast, Pleasant Grove Creek located to the north, and agricultural land located to the south and west. However, several rural residences are located south of the project site, across Phillip Road. Additionally, the Creekview Specific Plan, the West Roseville Specific Plan, Regional University Specific Plan, and the Amoruso Ranch Specific Plan are located near or within a two-mile radius of the project site.

The project would develop approximately 116 acres of land with 402,400 square feet (sf) of building area. The RRTO Facility would be located on the eastern portion of the site and strategically configured so that the public facing features such as the administrative office and employee/visitor parking are located relatively close to Phillip Road, while the more industrial features and operations of the site, such as waste unloading and transfer, are located further from Phillip Road. The Corporation Yard, composed of two primary areas: EU Services Facility and the Equipment Maintenance Facility, would be located on the eastern portion of the site. The Vendor Lease Area, which would potentially repurpose existing structures, would be located on the northeastern edge of the site. The maximum building height would reach as much as 70 feet above grade at the peak of the building roof. Additionally, landscape setbacks and fencing would be provided around the perimeter of the project site as a buffer along Phillip Road and Pleasant Grove Creek. Any new landscaping would be water-efficient landscaping in compliance with the City of Roseville Water Efficient Landscape Ordinance (WELO). The existing rice and hay fields in and adjacent to the project site and owned by the City may continue to operate until the City needs those areas. Perimeter and internal fencing are anticipated to be a six-foot-tall chain-link fence, or equivalent. Screening along portions of the chain-link fence may be installed, as deemed necessary. The RRTO Facility, Corporation Yard, and Vendor Lease Area would be fenced separate from one another with gates providing controlled access between the facilities.

Additionally, overhead power lines would be extended from the existing power supply system located near the City power production site on Phillip Road east of Westbrook Boulevard to a new substation on the project site. The 60 kilovolt (kV) line would be extended along the south side of Blue Oaks Boulevard, starting at the southeast corner of Westbrook Boulevard, turning north at Phillip Road, to a new substation on the Phillip Road project site (this portion of the alignment is included as part of the proposed Phillip Road Project and the environmental impacts of installing this portion of the alignment are evaluated in the Phillip Road Draft EIR). From the Phillip Road project site, the power line would be extended north to the western part of Phillip Road, where it would be extended along the north side of Phillip Road to the Roseville EU Operations Center project site. A 35-foot-wide public utility easement would be needed along the north side of Phillip Road. Although a portion of the 60 kV line is planned to be installed as part of the proposed Phillip Road Project, as noted above, the full length of the 60 kV line is addressed in this EIR for completeness. These power lines would be substantially taller (approximately 70 feet tall) than proposed buildings and existing trees and vegetation; however, they would be similar in nature to typical power lines in the area. The overhead power lines would be visible along Blue Oaks Boulevard and Phillip Road, but these would be visually consistent with the character of these roadway corridors and existing overhead lines (as shown in Figures 3.1-3 and

3.1-6), blending in with the existing surrounding development.

The PGSRB site is located northwest of the project site. As described in Section 3.1.2, “Environmental Setting,” views within the PGSRB site have a high vividness and moderate to high visual intactness and unity. Development of Phase

Ascent Aesthetics and Visual Resources
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Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-15 1 could degrade the PGSRB site’s visual quality by placing municipal development adjacent to the PGSRB Facility, especially because there would be an abrupt transition between open space and development. The City of Roseville General Plan includes Policy LU9.9, which states that development proposed on the western edge of the City shall provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained. The project has been designed to concentrate development in the southern portion of the project site, away from the nature preserve and creek. The northernmost portion of the project site, which is directly adjacent to Pleasant Grove Creek and the preserve, would remain undeveloped as rice and hay fields until the City needs the area. This would provide an open space transition between the project development and the creek and nature preserve. As described above, residential development in the area is already planned and, in some cases, under construction. Thus, development is already part of the visual landscape in this area. Due to its distance from major thoroughfares and the generally flat terrain of the area, there are no public views of the nature preserve that would be obstructed by the project.

As mentioned above in Section 3.1.2, “Environmental Setting,” the visual character of the project site is moderate. As shown in Figures 3.1-4, 3.1-5, and 3.1-6, the majority of the project site is covered in annual grassland that is contiguous with close-by agricultural parcels. Several unique visual patterns are present, including vegetation transitions marked by Pleasant Grove Creek. Pleasant Grove Creek combined with the annual grassland creates striking visual patterns, which adds to the moderate visual vividness of the project site. Additionally, the rural, undeveloped landscape surrounding the project site, as seen in Figures 3.1-2 and 3.1-3, is generally free of encroaching human-made elements, aside from utility lines, roadways, and fences.

The proposed development associated with Phase 1 would substantially alter the visual character of the project site from undeveloped agricultural land to municipal development. However, the visual character of the project site is moderate, similar to surrounding agricultural lands, and is generally not unique or distinctive relative to the visual character of the surrounding region, which is also dominated by agricultural land. Furthermore, Phase 1 would include landscaping, as described above, that would soften views of the site and would provide a buffer between the site and neighboring uses. In addition, given the project site’s proximity to the rural residences to the south and the four specific plan areas with varying plans of development from residential to commercial, the proposed industrial facilities would be designed to be visually consistent and would comply with the Roseville General Plan policies and the City’s Community Design Guidelines. Further, project design would include the following: (a) a coordinated color palette of no more than three muted tones, (b) articulated wall planes at least every 100 feet, (c) architectural wainscot or concrete stem wall on public-facing (south) elevation, and (d) screened mechanical equipment. Final design plans would be reviewed and approved by the Planning Division to ensure consistency.

Roseville General Plan policies and the City’s Community Design Guidelines promote the visual compatibility of developments through the application of community design standards. Specifically, Community Design Guidelines identify site planning and architectural design standards for new development, landscaping and screening techniques to preserve and enhance the visual quality, and lighting design and provisions to promote public safety and reduce glare and light spillover onto adjacent properties. The project would be required to comply with the General Plan policies and the City’s Community Design Guidelines. Nonetheless, the project would introduce waste and recycling collection trucks to the area, which occasionally contribute to litter. This could create a visual nuisance and could degrade the visual character of the project area. For these reasons, this impact would be potentially significant.

Mitigation Measures
Mitigation Measure 3.1-1: Implement a Litter Mitigation Program Once the project is operational, the City Solid Waste Division shall fund a continuous litter mitigation program that includes collecting and disposing roadside litter from along the roadways tributary to the site daily (Monday-Friday) on public roads within 1 mile of the project site and weekly within 2 miles of the project site. The litter mitigation program shall include routine monitoring of where litter occurs, logging of complaints, and the deployment of staff to perform litter removal activities. The City shall report the effectiveness of the litter mitigation program to the Local Enforcement Agency. The Solid Waste Division shall also employ a litter management program that collects litter from the site, its fences, and roadways each operating day.

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3.1-16 Roseville Environmental Utilities Operations Center Project Draft EIR Significance after Mitigation
Implementation of Mitigation Measure 3.1-1 would require implementation of a litter mitigation program to minimize litter generated by the project. Implementation of this program would include collecting and disposing of litter from the project site and affected roadways such that litter would not substantially increase beyond existing conditions.

Effects on visual character of the site and its surroundings would be minimized and the project impact would be reduced to a less-than-significant level.

Phase 2
Development of Phase 2 would convert approximately 34 acres of predominantly agricultural land owned by the City into municipal uses, including expansion of the RRTO Facility and construction of a Potential Future Organics Processing Facility. The introduction of municipal uses and infrastructure in an area that is predominantly agricultural would change the existing character of the area. However, the proposed facilities would be designed to be visually consistent and would be required to comply with General Plan policies related to community design and the City’s Community Design Guidelines. Nonetheless, the project would introduce waste and recycling collection trucks to the area, which occasionally contribute to litter. This could create a visual nuisance and could degrade the visual character of the project area. For these reasons, this impact would be potentially significant.

Similar to Phase 1, development of Phase 2 would change the existing visual character of the area both temporarily during construction and permanently during operation of the proposed EU Operations Center.

Construction
Similar to Phase 1, construction activities would reduce the vividness, unity, and intactness of the project site’s existing visual character by introducing encroaching human elements into the natural landscape. Construction equipment and materials would be present in the project area and visible to sensitive viewer groups, including motorists and residents.

Building materials and equipment would be staged in various locations on the project site throughout the duration of construction and would vary as Phase 2 is constructed. Visual impacts from construction would be temporary and limited to the construction period. As described in Chapter 2, “Project Description,” construction of the Potential Future Organics Processing Facility is intended to begin in 2035, with the facility becoming operational by 2040. The expanded RRTO Facility would be constructed on an as-needed basis but would become operational as early as 2040.

Given that the visual impact from construction would be temporary and that construction is occurring in the vicinity of the project (and is therefore part of the visual landscape), Phase 2 would not substantially degrade the visual character of the area during construction. This impact would be less than significant.

Operation
Phase 2 would develop approximately 34 acres of land and 159,000 sf of building area. The expanded RRTO Facility would be located on the eastern portion of the site and strategically configured so that the public facing features such as the administrative office and employee/visitor parking are located relatively close to Phillip Road, while the more industrial features and operations of the site, such as waste unloading and transfer, are located further from Phillip Road. The Potential Future Organics Processing Facility, which would be a compost facility and/or a biomass to energy facility, would be located in the northeastern portion of the project site. The existing rice and hay fields in and adjacent to the project site and owned by the City are expected to remain in agricultural production. Perimeter and internal fencing are anticipated to be a six-foot-tall chain-link fence, or equivalent. Screening along portions of the chain-link fence may be installed, as deemed necessary. The RRTO Facility and Potential Future Organics Processing Facility would be fenced separate from one another with gates providing controlled access between the two facilities.

Similar to Phase 1, development of Phase 2 could degrade the PGSRB site’s visual quality by placing municipal development near the PGSRB Facility, especially because there would be an abrupt transition between open space and development. The City of Roseville General Plan includes Policy LU9.9, which states that development proposed on the western edge of the City shall provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained.

As described for Phase 1, the project has been designed to concentrate development in the southern portion of the project site, away from the nature preserve and creek, providing an open space transition between the project development and the creek and nature preserve.

Ascent Aesthetics and Visual Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-17 The proposed development associated with Phase 2 would continue to alter the visual character of the project site by converting undeveloped agricultural land to municipal development. However, Similar to Phase 1, Phase 2 would be designed to be visually consistent and would comply with the Roseville General Plan policies and the City’s Community Design Guidelines. Further, project design would include the following: (a) a coordinated color palette of no more than three muted tones, (b) articulated wall planes at least every 100 feet, (c) architectural wainscot or concrete stem wall on public-facing (south) elevation, and (d) screened mechanical equipment. Final design plans would be reviewed and approved by the Planning Division to ensure consistency.

The project would be required to comply with the General Plan policies and the City’s Community Design Guidelines, as described above for Phase 1. Nonetheless, the project would introduce waste and recycling collection trucks to the area, which occasionally contribute to litter. This could create a visual nuisance and could degrade the visual character of the project area. For these reasons, this impact would be potentially significant.

Mitigation Measures
Implement Mitigation Measure 3.1-1, described above.

Significance after Mitigation
Implementation of Mitigation Measure 3.1-1 would require implementation of a litter mitigation program to minimize litter generated by the project. Implementation of this program would include collecting and disposing of litter from the project site and affected roadways such that litter would not substantially increase beyond existing conditions.

Effects on visual character of the site and its surroundings would be minimized and the project impact would be reduced to a less-than-significant level.

Impact 3.1-2: Create a New Source of Substantial Light or Glare That Would Adversely Affect Day or Nighttime Views in the Area
Phase 1
Phase 1 implementation would result in an increase in the amount of light and glare on the project site, which would affect nighttime views in the area. The project would adhere to the CALGreen Building Regulations, Title 24 Outdoor Lighting Standards, and General Plan Policy LU7.9. However, given the scale of the proposed project and the number and types of new light sources to be introduced to an undeveloped site, operation of the proposed project would represent a substantial source of new nighttime lighting in the project area, this impact would be significant.

Minimal sources of light or glare are present on the undeveloped project site. Sources of nighttime light around the project site are also minimal. Residential neighborhoods associated with the Creekview Specific Plan, West Roseville Specific Plan, and Amoruso Specific Plan area create some nighttime light that can be seen from the project site. With the exception of remnants of a former pheasant club, agricultural support structures, and a former residence, no structures are present on the project site that create shadows. The trees surrounding the existing structures and Pleasant Grove Creek provide shade to the creek and shadows on the project site.

Views of the project site from the unincorporated Placer County are similar to those from the City and, after development of the project, views of the project facilities would be similar for nearby viewers regardless of their location. As described above, the area is predominately agricultural/rural (including unincorporated Placer County) and existing nighttime light sources on and around the project site are minimal.

Development of Phase 1 would result in an increase in the amount of light and glare on the project site, which would affect nighttime views in the area both temporarily during construction and permanently during operation of the proposed EU Operations Center. This change in light and glare could adversely affect surrounding viewers both within the City and in unincorporated Placer County. These impacts are discussed below.

Construction
Glare would be introduced to the project area during construction from windshields of vehicles and construction equipment. These would be small sources of glare, would be at ground level, and would not adversely affect daytime

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3.1-18 Roseville Environmental Utilities Operations Center Project Draft EIR views of the area. Additionally, construction activities would occur during daytime hours. Security lighting may be used on-site at night and would represent a new source of lighting. As described in Chapter 2, “Project Description,” construction of the RRTO Facility and Vendor Lease Area is intended to begin spring 2027 and end late fall 2028, with Phase 1 becoming operational by 2028. The Corporation Yard would be constructed on an as-needed basis but would become operational as early as 2028. Following completion of Phase 1, construction activities would cease and the impact associated with glare and lighting would be temporary. Additionally, active construction associated with the surrounding specific plans is occurring within a two-mile radius of the project site, and this is expected to coincide with project construction. The surrounding construction would include glare/lighting during both the day and night; therefore, the project’s increase to this lighting would be incremental. Given the temporary nature of construction and the surrounding development of specific plan areas, project construction would have a less-than-significant impact related to light or glare.

Operation
Implementation of Phase 1 of the project would result in the addition of several on-site structures with metal and other reflective surfaces (e.g., glass) associated with the RRTO, Corporation Yard, and Vendor Lease Area facilities and parked cars in the parking lot at a site that is currently undeveloped. Glare could also be introduced from new parking lots, signs, and roadway surfaces. These facilities would also include exterior night lighting, including parking lot lighting and lighting of the electrical substation. The proposed buildings would be built with materials that could be reflective and cause an increase in glare sources. The addition of reflective surfaces would increase daytime glare on the project site, which is currently void of light and glare sources. The addition of nighttime lighting from the project could result in skyglow and light pollution if lights are cast in an upward direction, which could adversely affect surrounding viewers. Outdoor lighting for the facilities would consist of pole and/or building mounted lighting to provide appropriate illumination for night operations and safety. Lights would employ cut-off type lights to minimize off-site light pollution and skyglow.

To reduce the impact of lighting and glare from operation, design of the project’s facilities would be required to comply with CALGreen Building Regulations, Title 24 Outdoor Lighting Standards, and General Plan Policy LU7.9 to reduce light spillage and glare on adjacent properties and in private spaces. However, given the scale of the proposed project and the number and types of new light sources to be introduced to an undeveloped project site, operation of the proposed project would represent a substantial source of new nighttime lighting and glare in the project area that could adversely affect surrounding viewers both within the City and in unincorporated Placer County. This impact would be significant.

Mitigation Measures
Mitigation Measure 3.1-2: Minimize Potential Sources of Light and Glare The City shall implement the following design standards to minimize potential sources of light and glare, which are based on measures in the City’s Design Guidelines for office and industrial projects:
 Lighting sources shall have full cut off, U0 lenses and shall be located to avoid any light spillage and glare on adjacent properties and in private spaces;
 Pole mounted lighting shall be spaced for maximum energy efficiency and be no taller than 25 feet for office areas and 35 feet for industrial areas; and
 Nonreflective exterior surfaces and nonreflective (mirrored) glass shall be used for all new structures.

Significance after Mitigation
Implementation of Mitigation Measure 3.1-2 would require implementation of design standards to minimize potential sources of light and glare. These standards include the use of cutoff type light fixtures, restrictions on the height of pole mounted lighting, and the use of nonreflective surfaces for new structures. Adherence to these standards and compliance with applicable regulations would limit impacts such that skyglow and light spillage would not substantially increase beyond existing conditions. Effects on daytime and nighttime views from new sources of light and glare would be minimized and the project impact would be reduced to a less-than-significant level.

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City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.1-19 Phase 2
Phase 2 implementation would result in development of a Potential Future Organics Processing Facility and expanded RRTO facilities, which would introduce new light and glare sources and potentially affect nighttime views in the area.

The project would adhere to CALGreen Building Regulations, Title 24 Outdoor Lighting Standards, and General Plan Policy LU7.9. Most of the project lighting would be installed as part of Phase 1; however, Phase 2 would add an incremental amount of lighting and glare associated with the new and expanded facilities. This incremental change in lighting and glare would be significant.

Similar to Phase 1, development of Phase 2 would result in an incremental increase in the amount of light and glare on the project site, which would affect nighttime views in the area both temporarily during construction and permanently during Phase 2 operation of the proposed EU Operations Center. These impacts are discussed below.

Construction
Similar to Phase 1, light and glare would be introduced to the project area during construction of Phase 2 from windshields of vehicles and construction equipment. Security lighting may be used on site at night and would represent a new source of lighting. Following completion of Phase 2, construction activities would cease and the impact associated with lighting and glare would be temporary. Given the temporary nature of Phase 2 construction and the surrounding development associated with specific plan areas, project construction would have a less-thansignificant impact related to light and glare.

Operation
Phase 2 of the project would add metal and other reflective surfaces (e.g., glass) associated with the expanded RRTO and Potential Future Organics Processing Facility and parked cars in the parking lot. These facilities would also include exterior night lighting, including parking lot lighting and lighting of the electrical substation. Similar to Phase 1, the proposed buildings would be built with materials that could be reflective and cause an increase in glare sources at a site that is currently undeveloped. Glare could also be introduced from new parking lots, signs, and roadway surfaces.

Additionally, the addition of nighttime lighting could result in skyglow and light pollution if lights are cast in an upward direction. Outdoor lighting for the facilities would consist of pole and/or building mounted lighting to provide appropriate illumination for night operations and safety. Lights would employ cut-off type lights to minimize off-site light pollution and skyglow.

As described above for Phase 1, design of the project’s facilities would be required to comply with CALGreen Building Regulations, Title 24 Outdoor Lighting Standards, and General Plan Policy LU7.9 to reduce light spillage and glare.

Most of the project lighting would be installed as part of Phase 1; however, Phase 2 would add an incremental amount of lighting and glare associated with the new and expanded facilities. This incremental change in lighting and glare would be significant.

Mitigation Measures
Implement Mitigation Measure 3.1-2, described above.

Significance after Mitigation
Implementation of Mitigation Measure 3.1-2 would require implementation of design standards to minimize potential sources of light and glare. These standards include the use of cutoff type light fixtures, restrictions on the height of pole mounted lighting, and the use of nonreflective surfaces for new structures. Adherence to these standards and compliance with applicable regulations would limit impacts such that skyglow and light spillage would not substantially increase beyond existing conditions. Effects on daytime and nighttime views from new sources of light and glare would be minimized and the project impact would be reduced to a less-than-significant level.

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3.1-20 Roseville Environmental Utilities Operations Center Project Draft EIR This page is intentionally left blank.

Ascent Land Use Planning and Agricultural Resources
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Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-1

3.2 LAND USE PLANNING AND AGRICULTURAL RESOURCES
This land use analysis evaluates consistency of the proposed Roseville Environmental Utilities Operations Center with applicable land use plans and policies. The physical environmental effects associated with the project, many of which pertain to issues of land use compatibility (e.g., noise, aesthetics, air quality) are evaluated in other sections of Chapter 3 of this Draft EIR.

This section also describes existing agricultural resources on the project site and evaluates potential impacts associated with the conversion of the loss of Prime Farmland, Unique Farmland, and Farmland of Statewide or Local Importance (collectively, Farmland); and Williamson Act contracted land. The issues of forest land as defined in Public Resources Code (PRC) Section 12220(g) and timberland as defined by PRC Section 4526 are addressed in Chapter 1, “Introduction,” under “Effects Found Not to be Significant” because the project site and surrounding lands are not designated or zoned as forest land or timberland.

Two comment letters regarding land use planning and agricultural resources were received in response to the notice of preparation (see Appendix A). Placer County and the Placer Conservation Authority expressed concerns regarding land use conversion and conflicts with adjacent land uses, including potential conflicts with land conservation programs that are near the project site along the Pleasant Creek corridor. Direct and indirect effects of the conversion of lands from semi-natural habitat (i.e. rice fields on-site) into urban developed land and potential impacts on nearby rural and agricultural land uses are addressed below.

3.2.1 Regulatory Setting

FEDERAL
No federal plans, policies, regulations, or laws are applicable to the provision of land use or agricultural resources for the project.

STATE
Planning and Zoning Laws
California Government Code Section 65300 et seq. establishes the obligation of cities and counties to adopt and implement general plans. The General Plan is a comprehensive, long-term, planning document for the physical development of a city or county and of any land outside its boundaries that, in the city’s or county’s judgment, bears relation to its planning. The General Plan addresses a broad range of topics, including at a minimum land use, circulation, housing, conservation, open space, noise, environmental justice, and safety. In addressing these topics, the general plan identifies the goals, objectives, policies, principles, standards, and plan proposals that support the city’s or county’s vision for the area.

The State Zoning Law (California Government Code, Section 65800 et seq.) establishes that zoning ordinances, which are laws that define allowable land uses within a specific zoning district, are required to be consistent with the general plan. Local general plan policies and zoning ordinances, as they relate to the proposed project, are summarized below.

California Department of Conservation Farmland Mapping and Monitoring Program Farmland in California is classified and mapped according to the California Department of Conservation’s (DOC) Farmland Mapping and Monitoring Program (FMMP). Authority for the FMMP comes from Government Code Section 65570(b) and PRC Section 612. Government Code Section 65570(b) requires the DOC to collect or acquire information on the amount of land converted to or from agricultural use for every mapped county and to report this information to the Legislature. PRC Section 612 requires the DOC to prepare, update, and maintain Farmland Series Maps and other soils and land capability information.

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City of Roseville

3.2-2 Roseville Environmental Utilities Operations Center Project Draft EIR The California Land Conservation Act of 1965
The California Land Conservation Act of 1965, or the Williamson Act, preserves agricultural and open space lands through property tax incentives and voluntary restrictive use contracts. Private landowners voluntarily restrict their land to agricultural and compatible open-space uses under minimum 10-year rolling term contracts. In return, restricted parcels are assessed for property tax purposes at a rate consistent with their actual use, rather than potential market value.

LOCAL
City of Roseville General Plan
The Land Use Element of the City of Roseville General Plan (2020a) contains the following policies that may be applicable to the project:
 Policy LU1.5: Promote land use patterns that result in the efficient use of urban lands and preservation of open space, as specified in the Open Space and Conservation Element.  Policy LU5.1: Implement a land use mix and pattern of development that provides linkages between residents’ jobs and local employment-generating uses, facilitates a match between the number and type of local jobs and the local labor force, and maintains the fiscal viability of the City.  Policy LU5.6: Maintain land use patterns, intensities, and densities that ensure an adequate supply of land for office, commercial, industrial, and other employment-generating development.  Policy LU5.7: Support activities that attract employment uses to the City, as identified in the Economic Development Strategy.
 Policy LU8.4: The City shall accommodate projected population and employment growth in areas where the appropriate level of public infrastructure and services are planned or will be made available concurrent with development.
 Policy LU9.1: The City may consider modification to the General Plan for new growth where adequate public services and facilities and preservation and conservation of natural resources can be provided in conjunction with the following:
a. Additional land to accommodate demand for housing or employment uses b. Projects that will provide community benefits, including, but not limited to the provision of public transit services
c. Ensure that growth provides benefits to the community as a whole and weigh community benefits against public costs
 Policy LU9.6: As new development is proposed in or outside the City’s Sphere of Influence, project proponents shall provide a transitional area between City and County lands, through a system of managed interconnecting open space or other buffers, such as separation by arterial roadways.  Policy LU9.9: Development proposed on the western edge of the City shall provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained.

There are no General Plan policies related to agricultural resources that are applicable to the project.

City of Roseville Zoning Ordinance
The City of Roseville’s Zoning Ordinance (Title 19 of the Roseville Municipal Code) is the key regulatory tool meant to implement the General Plan, specifically the Land Use Element. The purpose of the ordinance is to protect and promote the public health, safety, and welfare of the city and to provide the economic and social advantages that result from an orderly, planned use of the environment. The Zoning Ordinance establishes specific, enforceable

Ascent Land Use Planning and Agricultural Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-3 standards with which development must comply such as minimum lot size, maximum building height, minimum building setback, and a list of allowable uses. Zoning applies on a parcel-by-parcel basis, whereas the General Plan has a community-wide perspective.

Sacramento Area Council of Government’s 2025 Blueprint
On November 20, 2025, the Sacramento Area Council of Governments (SACOG) approved the 2025 update of the Metropolitan Transportation Plan/Sustainable Communities Strategy (MTP/SCS, referred to as the 2025 Blueprint). An MTP is a long-range (at least 20 years) comprehensive plan that is required for the region to qualify for some federal and state transportation funding for public transit, streets/roads, and bicycle and pedestrian improvements. Under California’s Sustainable Communities and Climate Protection Act, or Senate Bill 375 (Statutes of 2008, Chapter 728), SACOG is required to adopt an SCS as part of every MTP. The SCS must align transportation, housing, and land use decisions to help achieve the per-capita reduction targets for greenhouse gas (GHG) emissions from passenger vehicles that are set by the California Air Resources Board. The 2025 Blueprint aims to achieve various federal, state, regional, and local policy objectives related to sustainable development, transportation, and GHG emission reduction while considering financial, growth, and regulatory constraints.

The regional growth projections for the 2025 Blueprint were adopted by the SACOG board in 2022 and anticipate that the region will grow by approximately 580,000 people, and will add just over 260,000 new jobs, and 278,000 new homes. The 2025 Blueprint is designed to achieve the regional SB 375 GHG target while prioritizing maintenance and rehabilitation of existing infrastructure. It integrates smart land use planning principles with a diverse and efficient transportation network. The plan identifies targeted transportation investments, including new capital improvements (e.g., highways, roads, bridges, and light rail), policies such as roadway pricing strategies (e.g., tolling and mileage fees), and multimodal benefits aimed at connecting housing to jobs, managing congestion, and addressing forecasted travel volumes.

The 2025 Blueprint contains the following policies that may be applicable to the project (SACOG 2025):
 Policy Vibrant-1: Provide incentives, information, tools, technical assistance, and encouragement for legislative and regulatory reform and investment in Center & Corridor and Established Communities that increase housing options, jobs and services, and access to amenities.
 Policy Vibrant-3: Encourage local policy reforms that facilitate missing middle housing, strategically allow for higher-density housing, transition from discretionary to by-right development review, reduce governmentmandated parking requirements, incentivize accessory dwelling units, and reduce displacement by protecting tenants and funding subsidized affordable housing.
 Policy Vibrant-6: Coordinate strategically phased growth in Developing Communities that expands the region’s footprint in ways that minimize impacts on working lands and habitat and create complete communities with jobs, housing choices, connected streets, and convenient access to public transportation.  Policy Vibrant-7: Support the implementation of SACOG’s Regional Housing Needs Plan by affirmatively furthering fair housing, taking proactive steps to overcome patterns of residential segregation, clearing barriers to housing in high opportunity areas, and supporting other activities identified by local governments in adopted housing elements.
 Policy Build-7: Support investments in bicycle and pedestrian infrastructure that provides safe access to schools, jobs, recreational opportunities, social gathering centers, and transit, and/or implements the Regional Trail Network
 Policy Build-8: Develop multimodal corridors that improve access to major economic assets and job centers and facilitate the reliable movement of freight.

Land Use Planning and Agricultural Resources Ascent
City of Roseville

3.2-4 Roseville Environmental Utilities Operations Center Project Draft EIR

3.2.2 Environmental Setting

LAND USE
Surrounding Land Uses
The project site is in the northwest corner of the City of Roseville, in Placer County. The planned Pleasant Grove Stormwater Retention Basin Facility would be located to the east and the Reason Farms Preserve is located to the northeast of the project site. Agricultural uses are located to the west and south of the project site. Pleasant Grove Creek is along the project site’s northern boundary. To the east, in an approximately 2-mile radius are the Creekview Specific Plan, West Roseville Specific Plan, Regional University and Community, and Amoruso Ranch Specific Plan areas, that are residential planned developments, at various stages of development, which will include residential units, open space, parks, and commercial and industrial land uses. The Phillip Road Site Project (formerly known as the Roseville Industrial Park Project) is a proposed mixed-use development that would be located approximately two miles east of the project site.

The project site is located within the city limits and is surrounded by unincorporated Placer County to the north, west, and south (Figure 3.2-1). Within the City, land to the east of the project site is designated as Public/Quasi-Public, which allows for municipal, governmental or public facilities, places of worship, and related uses. Within the unincorporated County, land to the north, west, and south of the project site is designated as Farm and Agriculture/Timberland, which allows for preserved natural lands, passive recreation and minor recreation facilities, mitigation, and drainage detention.

Project Site
The project site is located north of Phillip Road and south of Pleasant Grove Creek on approximately 243 acres of undeveloped agricultural land. Although the project site is 243 acres in size, the total development area is currently anticipated to be approximately 150 acres, as evaluated in this EIR, and focused within the southern portion of the project site. The remaining 93 acres are within the Pleasant Grove Creek Floodplain. Table 3.2-1 identifies and categorizes the site acreage.

Table 3.2-1 Site Acreage
Acreage (approximate)
Phase 1 116
Phase 2 34
Land not planned for development at the project site 93 Total Site Acreage 243
Source: Provided by HDR in 2025.

Several structures are located on the site, which are remnants from a former pheasant club, agricultural support structures, and a former residence.

The project site includes portions of Assessor’s Parcel Numbers (APNs) 017-010-033-000, 017-090-054-000, and 017- 090-055-000. The existing General Plan land use designation for the project site is Public/Quasi-Public (P/QP), which establishes areas for municipal, governmental, or public facilities. The zoning for the project site is Planned Development (PD). A PD District is a special purpose district that is intended to be applied in circumstances where the desired mix of uses cannot be achieved with a residential, commercial, or industrial mixed-use district when combined with a special area overlay (Figure 3.2-1).

Ascent Land Use Planning and Agricultural Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-5 Source: Data downloaded from City of Roseville and Placer County in 2025.

Figure 3.2-1 Land Use and Zoning

Land Use Planning and Agricultural Resources Ascent
City of Roseville

3.2-6 Roseville Environmental Utilities Operations Center Project Draft EIR

AGRICULTURAL RESOURCES
Farmland Classification
The State of California maps and classifies farmland through the DOC FMMP. Classifications are based on a combination of physical and chemical characteristics of the soil and climate that determine the degree of suitability of the land for crop production. The classifications under the FMMP are as follows:
 Prime Farmland—land that has the best combination of features for the production of agricultural crops;  Farmland of Statewide Importance—land other than Prime Farmland that has a good combination of physical and chemical features for the production of agricultural crops, but that has more limitations than Prime Farmland, such as greater slopes or less ability to store soil moisture;  Unique Farmland—land of lesser quality soils used for the production of the state’s leading agricultural cash crops;  Farmland of Local Importance—land of importance to the local agricultural economy;  Grazing Land—existing vegetation that is suitable for grazing;  Urban and Built-Up Land—land occupied by structures in density of at least one dwelling unit per 1.5 acres;  Land Committed to Nonagricultural Use—vacant areas; existing land that has a permanent commitment to development but has an existing land use of agricultural or grazing lands; and  Other Land—land not included in any other mapping category, common examples of which include low-density rural developments, brush, timber, wetland, and vacant and nonagricultural land surrounded on all sides by urban development.

CEQA Section 21095 and CEQA Guidelines Appendix G, together, define Prime, Unique, and Farmland of Statewide Importance as “Farmland,” the conversion of which may be considered significant. Local jurisdictions can further consider other classifications of farmland as important and can also use an agricultural land evaluation and site assessment model to determine farmland importance and impacts from conversion.

Existing Farmland
Agricultural lands including row crops, grain crops, orchards, and grassland that support livestock grazing are located in the west and northwest areas of the city and south of the project site. The City of Roseville does not contain any lands zoned for agricultural uses (City of Roseville 2020b).

Lands immediately north, west, and south of the project site are within Placer County and are in active agriculture production. Lands surrounding the project site are designated as Prime Farmland, Unique Farmland, Farmland of Local Importance, and Grazing Land, and Other Land (Figure 3.2-2).

The project site is currently leased for rice and hay farming and has been used historically for agricultural purposes. The project site is designated by the DOC’s FMMP as Prime Farmland, Unique Farmland, Farmland of Local Importance, Grazing Land, and Other Land (Table 3.2-2 and Figure 3.2-2). Within the 150-acre proposed development area, land is designated as Prime Farmland, Unique Farmland, Farmland of Local Importance, and Other Land.

Table 3.2-2 Farmland Designation Acreage
Acreage on project site (approximate) Acreage planned for development (approximate) Prime Farmland 7 1
Unique Farmland 189 105
Farmland of Local Importance 33 31
Grazing Land 3 2
Other Land 11 11
Total Acreage 243 150
Source: 2018 FMMP data downloaded from DOC in 2025.

Ascent Land Use Planning and Agricultural Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-7 Sources: Downloaded from CA Dept. of Conservation (FMMP) in 2024; adapted by Ascent in 2025.

Figure 3.2-2 Farmland Designations

Land Use Planning and Agricultural Resources Ascent
City of Roseville

3.2-8 Roseville Environmental Utilities Operations Center Project Draft EIR A portion of the project site (an 11-acre parcel that includes the 5-acre Vendor Lease Area) is mistakenly under a Williamson Act contract. In 1996, the former owners of the Warnick/Plunkette property, which includes the project site, entered the land into a Williamson Act contract. After purchasing the land in 2003, the property was subdivided and the City requested removal of the land from the Williamson Act contract in 2012; however, the 11-acre parcel was inadvertently not included in the request. Thus, while the rest of the land was removed from the Williamson Act contract in 2012, the Vendor Lease Area remains under a Williamson Act contract. This 11-acre parcel, however, is not actively used as agricultural land nor is it being conserved as farmland.

3.2.3 Environmental Impacts and Mitigation Measures

METHODOLOGY
Land Use
Evaluation of potential land use impacts is based on a review of documents pertaining to the project site, including the City of Roseville General Plan 2035 (2020a), 2035 General Plan Update Final Environmental Impact Report (2020b), and Draft Environmental Impact Report for the City of Roseville Detention Basin (City of Roseville 2002). In determining the level of significance, this analysis assumes that the project would comply with relevant state and local ordinances and regulations related to land use.

Agricultural Resources
To evaluate potential impacts of the proposed project on agricultural resources, the type and degree of agricultural resources that would be lost/converted were considered in relation to FMMP designations of lands within the project site and any policies and programs related to the preservation of agricultural resources.

THRESHOLDS OF SIGNIFICANCE
Thresholds of significance are based on Appendix G of the State CEQA Guidelines. The project would have a significant impact related to land use if it would:
 physically divide an established community; or
 cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect.

The project would have a significant impact related to agricultural resources if it would:
 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;
 conflict with existing zoning for agricultural use, or a Williamson Act contract; or  involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland to non-agricultural use.

ISSUES NOT DISCUSSED FURTHER
The project site is in the northwest corner of the City of Roseville bordering agriculture/open space in Placer County.

The current General Plan land use designation for the project site is Public/Quasi-Public and the zoning is Planned Development. Pleasant Grove Creek borders the north side of the project site. The planned Pleasant Grove Stormwater Retention Basin Facility would be located to the east and the Reason Farms Preserve is located to the northeast of the project site. Other surrounding land uses include agriculture with supporting residential structures.

Planned developments and specific plan areas are located within a 2-mile radius of the project site and are at

Ascent Land Use Planning and Agricultural Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-9 different stages of development. Therefore, no part of the project would create a barrier within the established community and connectivity would be maintained through the site. Because project improvements would generally be limited to the project site (with the exception of off-site utility extensions and roadway improvements), and the project is located at the edge of the existing developed area of the city, the project would not divide an established community. Therefore, there would be no impact, and this issue is not discussed further.

The project site is not designated or zoned for agricultural use (City of Roseville 2020b). As described above, a portion of the project site (the Vendor Lease Area) is mistakenly under a Williamson Act contract, however, it is not actively used as agricultural land nor is it being conserved as farmland. Therefore, there would be no impact related to conflicts with agricultural zoning or Williamson Act contracts and these issues are not discussed further.

ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES
Impact 3.2-1: Conflict with any Land Use Plan, Policy, or Regulation Adopted for the Purpose of Avoiding or Mitigating an Environmental Effect
Phase 1
The existing General Plan land use designation for the project site is Public/Quasi-Public (P/QP), which establishes areas for municipal, governmental, or public facilities. The zoning for the project site is Planned Development (PD), which is a flexible zoning designation that allows for customized development standards and land uses tailored to a specific project or area. As a public facility, the project would be consistent with the Public/Quasi-Public land use designation and Planned Development zoning. No General Plan amendments or zoning changes would be required and, therefore, the project would be consistent with the City of Roseville General Plan and City of Roseville Zoning Ordinance. In addition, the project would not conflict with other land use plans in the project area. This impact would be less than significant.

The City of Roseville General Plan and City of Roseville Zoning Ordinance are the primary planning documents applicable to the project site. The project site is located on Phillip Road (near its western terminus at South Brewer Road) on 150 acres of a 243-acre parcel of undeveloped land in northwest Roseville.

The project site is predominantly agricultural in use and is leased for rice and hay farming. Several structures related to agriculture and former rural residential uses are located on the site. While the site is currently used for agricultural use, the existing General Plan land use designation for the project site is Public/Quasi-Public (P/QP), which establishes areas for municipal, governmental, or public facilities. The zoning for the project site is Planned Development (PD), which is a flexible zoning designation that allows for customized development standards and land uses tailored to a specific project or area. Because Phase 1 includes development of government offices and municipal corporation yard facilities, the project would be consistent with the land use designations and zoning established by the City of Roseville.

The project would comply with General Plan policies that have been adopted for the purpose of avoiding or mitigating an environmental effect, including Policy LU9.9, which requires development proposed on the western edge of the City to provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained. Phase 1 would be designed to concentrate development in the southern portion of the project site, away from Pleasant Grove Creek and the Reason Farms Preserve, located north and northeast of the project site, respectively. The northernmost portion of the project site would remain undeveloped as part of the project, and the existing rice and hay fields in and adjacent to the project site may continue to operate until the City needs those areas. Additionally, landscape setbacks and fencing would be provided around the perimeter of the project site as a buffer along Phillip Road and Pleasant Grove Creek. With the exception of the Country Acres Solar Project that is breaking ground south of the project site, no known development is planned for the area west of the project site. Thus, the existing open space and agricultural land to the west and north of the project site would continue to provide a transition between the City and County.

Land Use Planning and Agricultural Resources Ascent
City of Roseville

3.2-10 Roseville Environmental Utilities Operations Center Project Draft EIR In addition, the 2020 MTP/SCS includes policy considerations applicable to the project. These include objectives related to locating jobs in proximity to housing. The project is expected to generate more than 439 jobs during Phase 1 in proximity to several specific plan areas with a total of over 14,000 residential units that are in various stages of buildout. Additionally, the 2020 MTP/SCS includes goals to provide effective connections between people and jobs, which the project would do by being approximately 2 miles away from residential development and the future Placer Parkway in the City of Roseville that would provide connectivity between the project site and other areas of the city.

Policy 1 in the 2020 MTP/SCS encourages development in communities where services, amenities, and transportation infrastructure already exist; complete communities that include a balance of homes, jobs, services, amenities, and diverse transportation options; and complete streets that provide safe, comfortable, and equitable facilities for people of all ages and abilities to walk, bike, and ride transit. The project would provide jobs near existing and planned residential areas and would include transportation improvements to Phillip Road (including sidewalks). Although bicycle and transit facilities are not part of the project, development of the project site would not preclude the future installation of these facilities. Finally, although the project is proposed at the western edge of the City, it is not in conflict with the MTP/SCS goal regarding inwardly focused growth because this location is appropriate given the nature of the project and is within the City limits.

Therefore, because the project would be consistent with the existing land use designation and zoning for the project site, the project would also be consistent with land use plans, policies, and regulations applicable to the project site, including the City of Roseville General Plan and City of Roseville Zoning Ordinance. This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Phase 2
Implementation of Phase 2, like Phase 1, would be within land designated as P/QP and zoned PD. No General Plan amendments or zoning changes would be required and, therefore, the project would be consistent with the City of Roseville General Plan and City of Roseville Zoning Ordinance. Therefore, this impact would be less than significant.

Phase 2 would include expansion of the RRTO Facility and development of a Potential Future Organics Processing Facility on the project site. Similar to Phase 1, Phase 2 would be consistent with the land use designations and zoning established by the City of Roseville. No General Plan amendments or zoning changes would be required.

Additionally, Phase 2 would be consistent with General Plan policies that have been adopted for the purpose of avoiding or mitigating an environmental effect, including Policy LU9.9, which requires development proposed on the western edge of the City to provide a distinctive open space transition to create a physical and visual buffer between the City and County that ensures that the identity and uniqueness of the City and County will be maintained. As described for Phase 1, the existing open space and agricultural land to the west and north of the project site would continue to provide a transition between the City and County.

Additionally, similar to Phase 1, the project would be consistent with the 2020 MTP/SCS and the City/County MOU for development in the western part of the City. Thus, the proposed project would be consistent with land use plans, policies, and regulations applicable to the project site. This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Ascent Land Use Planning and Agricultural Resources
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.2-11 Impact 3.2-2: Result in the Conversion of Farmland
Phase 1
The project site has been used historically for agricultural purposes and is designated by the DOC’s FMMP as Prime Farmland, Unique Farmland, Farmland of Local Importance, Grazing Land, and Other Land. The conversion of Farmland of Local Importance, Grazing Land, or Other Land is not considered a significant impact under Appendix G of the State CEQA Guidelines. Prime and Unique Farmland is considered Important Farmland and its conversion is considered a significant impact under Appendix G of the State CEQA Guidelines. Therefore, this impact would be significant.

The project site has been used historically for agricultural purposes and is designated by the DOC’s FMMP as Prime Farmland, Unique Farmland, Farmland of Local Importance, Grazing Land, and Other Land (Figure 3.2-2). The conversion of Farmland of Local Importance, Grazing Land or Other Land is not considered a significant impact under Appendix G of the State CEQA Guidelines. Prime and Unique Farmland is considered Important Farmland, and its conversion is considered a significant impact under Appendix G of the State CEQA Guidelines. Based on estimates using existing FMMP Important Farmlands data and GIS mapping, it is estimated that the project would result in the conversion of approximately 1 acre of Prime Farmland and 105 acres of Unique Farmland (Table 3.2-2).

While the project site is leased for rice and hay production, the site has been designated to be used for a public stormwater retention basin for two decades and has been proposed for development for that length of time (City of Roseville 2020b). Nonetheless, because the project would convert Important Farmland to non-agricultural use, this impact would be significant.

Mitigation Measures
Mitigation Measure 3.2-2: Compensate for Important Farmland Conversion The following mitigation measure would be implemented to mitigate the project’s conversion of approximately 1 acre of Prime Farmland and 105 acres of Unique Farmland (a total of 106 acres of Important Farmland).

Prior to project construction, the City (Environmental Utilities Department) shall place a conservation easement on the Unique and Prime Farmland located within the project site but outside of the project development footprint, which includes 6 acres of Prime Farmland and 84 acres of Unique Farmland (as shown in Table 3.2-2). This permanent, onsite easement would mitigate for the loss of 90 acres of Important Farmland. Though there are no specific requirements for additional off-site preservation of farmland, the City will seek opportunities to provide for farmland conservation outside of the city within Placer County. This may be accomplished through the purchase of land or an easement, or providing funding for, Important Farmland conservation in Placer County. Should the City’s effort to create the on-site conservation easement prove impossible or impractical, the City may pay in-lieu fees to mitigate the equivalent farm value of farmland as close to the project area as feasible.

Significance after Mitigation
Implementation of Mitigation Measure 3.2-2 would reduce impacts associated with the conversion of Important Farmland, but not sufficiently to reduce the impact to a less-than-significant level because no new farmland would be made available. As a result, a net loss of Important Farmland would occur. After mitigation, this impact would be significant and unavoidable.

Land Use Planning and Agricultural Resources Ascent
City of Roseville

3.2-12 Roseville Environmental Utilities Operations Center Project Draft EIR Phase 2
Implementation of Phase 2, like Phase 1, would result in the conversion of Unique Farmland to non-agricultural use.

As described for Phase 1, the conversion of Unique Farmland is considered a significant impact under Appendix G of the State CEQA Guidelines. Therefore, this impact would be significant.

Phase 2 of the project would include an additional 122,000 square feet of building area for the RRTO Facility and the construction of 37,000 square feet of building area for the Potential Future Organics Processing Facility (including the development of 34 acres of land). Similar to Phase 1, construction of Phase 2 would convert Unique Farmland to nonagricultural use. Based on estimates using existing FMMP Important Farmlands data and GIS mapping, it is estimated that the project would result in the conversion of approximately 105 acres of Unique Farmland (Table 3.2-2).

While the project site is leased for rice and hay production, the site has been designated to be used for a public stormwater retention basin for two decades and has been proposed for development for that length of time (City of Roseville 2020b). Nonetheless, because the project would convert Important Farmland to non-agricultural use, this impact would be significant.

Mitigation Measures
Implement Mitigation Measure 3.2-2, described above.

Significance after Mitigation
Implementation of Mitigation Measure 3.2-2 would reduce impacts associated with the conversion of Important Farmland, but not sufficiently to reduce the impact to a less-than-significant level because no new farmland would be made available. As a result, a net loss of Important Farmland would occur. After mitigation, this impact would be significant and unavoidable.

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-1

3.3 AIR QUALITY
This section includes a summary of applicable air quality regulations, a discussion of existing air quality conditions, and an analysis of potential short- and long-term air quality impacts that could result from implementation of the project. The methods of analysis for short-term construction, long-term regional (operational), local mobilesource, and toxic air emissions and odors are consistent with the guidance from the Placer County Air Pollution Control District (PCAPCD), the California Air Resources Board (CARB), and the US Environmental Protection Agency (EPA). Mitigation measures are proposed as necessary to reduce significant air quality impacts.

One comment regarding air quality was received in response to the notice of preparation (see Appendix A). The Office of the Placer County Executive suggested that the EIR should analyze the air quality, dust, and odor impacts associated with project construction and operation and analyze health impacts to County residents. To assess potential health effects from the project, a health risk assessment (HRA) was conducted to evaluate both project construction and operational emissions. The results of the HRA are summarized in Impact 3.3-4 and detailed inputs and outputs are included in Appendix B.

3.3.1 Regulatory Setting
Air quality in the project area is regulated through the efforts of various federal, State, regional, and local government agencies. These agencies work jointly, as well as individually, to improve air quality through legislation, planning, policymaking, education, and a variety of programs. The agencies responsible for improving the air quality within the air basins are discussed below.

FEDERAL
US Environmental Protection Agency
EPA has been charged with implementing national air quality programs. EPA’s air quality mandates draw primarily from the federal Clean Air Act (CAA), which was enacted in 1970, and the most recent major amendments made by Congress in 1990. EPA’s air quality efforts address both criteria air pollutants and hazardous air pollutants (HAPs). EPA regulations concerning criteria air pollutants and HAPs are presented in greater detail below.

Criteria Air Pollutants
The CAA, 43 US Code Section 7401 et seq. (1970), is the comprehensive federal law that regulates air emissions from stationary and mobile sources. It’s intended to reduce and control air pollution nationally with major amendments in 1977 and 1990. The CAA defines EPA’s responsibilities for protecting and improving the nation’s air quality and the stratospheric ozone layer.

The CAA, in sections 108 and 109, requires EPA to establish National Ambient Air Quality Standards (NAAQS) for common air pollutants called “criteria air pollutants.” These are common in outdoor air, considered harmful to public health and the environment, and originate from numerous and diverse sources. The CAA requires EPA to periodically review these standards through scientific research to determine whether changes are warranted. The six criteria pollutants are carbon monoxide (CO), lead (Pb), respirable particulate matter (PM) with aerodynamic diameter of 10 micrometers or less (PM10) and fine particulate matter with aerodynamic diameter of 2.5 micrometers or less (PM2.5), ground-level ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2). These standards are shown in Table 3.3-1.

The primary standards protect public health and the secondary standards protect public welfare.

The CAA also required each state to prepare a state implementation plan (SIP) for attaining and maintaining the NAAQS. The SIPs are developed by state and local air quality management agencies and submitted to EPA for approval (EPA 2025a). The federal Clean Air Act Amendments of 1990 (CAA Amendments) added requirements for states with nonattainment areas to revise their SIPs to incorporate additional control measures to reduce air pollution.

California’s SIP is modified periodically to reflect the latest emissions inventories, planning documents, and rules and

Air Quality Ascent
City of Roseville

3.3-2 Roseville Environmental Utilities Operations Center Project Draft EIR regulations of the air basins as reported by their jurisdictional agencies. EPA is responsible for reviewing all SIPs to determine whether they conform to the mandates of the CAA and its amendments, and whether implementation will achieve air quality goals. If EPA determines a SIP to be inadequate, EPA may prepare a federal implementation plan that imposes additional control measures. If an approvable SIP is not submitted or implemented within the mandated time frame, sanctions may be applied to transportation funding and stationary air pollution sources in the air basin.

Table 3.3-1 National and California Ambient Air Quality Standards Pollutant Averaging Time California (CAAQS)a,b National (NAAQS)c

Primaryb,d
National (NAAQS)c
Secondaryb,e
Ozone 1-hour 0.09 ppm (180 μg/m3) –e Same as primary standard 8-hour 0.070 ppm (137 μg/m3) 0.070 ppm (147 μg/m3) Same as primary standard Carbon monoxide
(CO) 1-hour 20 ppm (23 mg/m3) 35 ppm (40 mg/m3) Same as primary standard 8-hour 9 ppmf (10 mg/m3) 9 ppm (10 mg/m3) Same as primary standard Nitrogen dioxide
(NO2) Annual arithmetic mean 0.030 ppm (57 μg/m3) 53 ppb (100 μg/m3) Same as primary standard 1-hour 0.18 ppm (339 μg/m3) 100 ppb (188 μg/m3) —
Sulfur dioxide (SO2) 24-hour 0.04 ppm (105 μg/m3) — —
3-hour — — 0.5 ppm (1300 μg/m3)
1-hour 0.25 ppm (655 μg/m3) 75 ppb (196 μg/m3) —
Respirable particulate
matter (PM10) Annual arithmetic mean 20 μg/m3 — Same as primary standard 24-hour 50 μg/m3 150 μg/m3 Same as primary standard
Fine particulate matter
(PM2.5) Annual arithmetic mean 12 μg/m3 12.0 μg/m3 15.0 μg/m3 24-hour — 35 μg/m3 Same as primary standard
Lead f Calendar quarter — 1.5 μg/m3 Same as primary standard 30-Day average 1.5 μg/m3 — —
Rolling 3-Month Average – 0.15 μg/m3 Same as primary standard Hydrogen sulfide 1-hour 0.03 ppm (42 μg/m3)
Sulfates 24-hour 25 μg/m3 No National standards
Vinyl chloride f 24-hour 0.01 ppm (26 μg/m3)
Visibility-reducing
particulate matter
8-hour Extinction of 0.23 per km
Notes: CAAQS = California ambient air quality standards; NAAQS = national ambient air quality standards; µg/m3 = micrograms per cubic meter; km = kilometers; ppb = parts per billion; ppm = parts per million. a California standards for ozone, carbon monoxide, SO2 (1- and 24-hour), NO2, particulate matter, and visibility-reducing particles are values that are not to be exceeded. All others are not to be equaled or exceeded. California ambient air quality standards are listed in the Table of Standards in Section 70200 of Title 17 of the California Code of Regulations. b Concentration expressed first in units in which it was promulgated. Equivalent units given in parentheses are based on a reference temperature of 25 degrees Celsius (°C) and a reference pressure of 760 torr. Most measurements of air quality are to be corrected to a reference temperature of 25°C and a reference pressure of 760 torr; ppm in this table refers to ppm by volume, or micromoles of pollutant per mole of gas. c National standards (other than ozone, particulate matter, and those based on annual averages or annual arithmetic means) are not to be exceeded more than once a year. The ozone standard is attained when the fourth highest 8-hour concentration in a year, averaged over three years, is equal to or less than the standard. The PM10 24-hour standard is attained when the expected number of days per calendar year with a 24-hour average concentration above 150 μg/m3 is equal to or less than one. The PM2.5 24-hour standard is attained when 98 percent of the daily concentrations, averaged over three years, are equal to or less than the standard. Contact the US Environmental Protection Agency for further clarification and current federal policies.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-3 d National primary standards: The levels of air quality necessary, with an adequate margin of safety to protect the public health. e National secondary standards: The levels of air quality necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.
f The California Air Resources Board has identified lead and vinyl chloride as toxic air contaminants with no threshold of exposure for adverse health effects determined. These actions allow for the implementation of control measures at levels below the ambient concentrations specified for these pollutants.

Source: CARB 2024.

Title V of the federal CAA, as amended in 1990, created an operating permit program for certain defined sources.

One of the primary Title V applicability criteria is based on the facility’s potential to emit, and the emission threshold varies by the attainment status of the local area. For example, owners/operators of industrial sources that emit more than 100 tons per year (tpy) of oxides of nitrogen (NOX) or volatile organic compounds (VOC) must possess a Title V permit. If a source is located in a federal ozone nonattainment area classified as “Serious Nonattainment,” this threshold is lowered to 50 tpy. For “Severe Nonattainment” areas, the threshold is lowered to 25 tpy, and for “Extreme Nonattainment” areas, the threshold is further lowered to 10 tpy. The lowering of the thresholds results in more businesses having to comply with Title V permitting requirements in areas with worse air quality. EPA defined the basic requirements of the Title V program under the Code of Federal Regulations (CFR) Title 40 Part 70, and each air district, including PCAPCD, has adopted rules specific to their area to implement the Title V program. The PCAPCD Title V program is discussed in the “Placer County Air Pollution Control District” section, below. Title V is not meant to impose any new air pollution standards, require installation of any new controls on the affected facilities, or require emissions reductions. It does, however, enhance public and EPA participation in the permitting process and requires additional recordkeeping and reporting by businesses, which may result in additional administrative requirements.

Hazardous Air Pollutants and Toxic Air Contaminants
Toxic air contaminants (TACs), or in federal parlance, HAPs, are a defined set of airborne pollutants that may pose a present or potential hazard to human health. A TAC is defined as an air pollutant that may cause or contribute to an increase in mortality or in serious illness, or that may pose a hazard to human health. TACs are usually present in minute quantities in the ambient air; however, their high toxicity or health risk may pose a threat to public health even at low concentrations.

A wide range of sources, from industrial plants to motor vehicles, emit TACs. The health effects associated with TACs are quite diverse and generally are assessed locally, rather than regionally. TACs can cause long-term health effects such as cancer, birth defects, neurological damage, asthma, bronchitis, or genetic damage, or short-term acute effects such as eye watering, respiratory irritation (a cough), running nose, throat pain, and headaches.

For evaluation purposes, TACs are separated into carcinogens and noncarcinogens based on the nature of the physiological effects associated with exposure to the pollutant. Carcinogens are assumed to have no safe threshold below which health impacts would not occur. This contrasts with criteria air pollutants for which acceptable levels of exposure can be determined and for which the ambient standards have been established (Table 3.3-1). Cancer risk from TACs is expressed as excess cancer cases per one million exposed individuals, typically over a lifetime of exposure.

EPA regulates HAPs through its National Emission Standards for Hazardous Air Pollutants. The standards for a particular source category require the maximum degree of emission reduction that the EPA determines to be achievable, which is known as the Maximum Achievable Control Technology—MACT standards. These standards are authorized by Section 112 of the 1970 CAA and the regulations are published in 40 CFR Parts 61 and 63.

Stationary Sources
New Source Performance Standards
New Source Performance Standards (NSPS), established under the CAA, are federal regulations designed to limit air pollution from specific industrial categories. These standards apply to newly constructed, modified, or reconstructed facilities, requiring them to employ the best available control technology (BACT) to minimize emissions. NSPS cover a wide range of pollutants, including particulate matter, sulfur dioxide, nitrogen oxides, volatile organic compounds, and hazardous air pollutants. The specific requirements of NSPS vary depending on the industry and pollutant, but

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3.3-4 Roseville Environmental Utilities Operations Center Project Draft EIR generally include emission limits, monitoring and reporting requirements, and operational and maintenance standards. By setting pollution control benchmarks for new sources, NSPS play a role in preventing the worsening of air quality and encouraging the development and implementation of cleaner technologies (EPA 2025b).

Mobile Sources
EPA has established a number of emission standards for on- and off-road heavy-duty diesel engines used in trucks and other equipment. These standards were established in part because diesel engines are a significant source of NOX, PM10, and PM2.5 and because EPA has identified diesel particulate matter as a probable carcinogen.

Implementation of the on-road heavy-duty diesel engine standards and the off-road heavy-duty diesel engine standards is estimated to reduce particulate matter and NOX emissions from diesel engines by up to 95 percent in 2030, by which time the regulation aims to have heavy-duty vehicle fleets completely replaced with newer heavy-duty vehicles that comply with these emission standards.

In concert with the diesel engine emission standards, EPA regulations have also substantially reduced the amount of sulfur allowed in diesel fuels. The sulfur contained in diesel fuel is a significant contributor to the formation of particulate matter in diesel-fueled engine exhaust. The new standards reduced the amount of sulfur allowed by 97 percent for highway diesel fuel (from 500 parts per million by weight [ppmw] to 15 ppmw), and by 99 percent for offhighway diesel fuel (from approximately 3,000 ppmw to 15 ppmw). The low-sulfur highway fuel (15 ppmw sulfur), also called ultra-low sulfur diesel, is currently required for use by all vehicles in the United States. All the aforementioned federal diesel engine and diesel fuel requirements have been adopted by California, in some cases with modifications making the requirements more stringent or the implementation dates sooner.

STATE
CARB is the agency responsible for coordination and oversight of State and local air pollution control programs in California and for implementing the California Clean Air Act (CCAA). The CCAA, which was adopted in 1988, required CARB to establish California Ambient Air Quality Standards (CAAQS) (Table 3.3-1).

California Ambient Air Quality Standards
Over the past 50 years, there have been hundreds of epidemiological and scientific studies published detailing the harmful effects of air pollution. Air pollution harms people’s health, damages agricultural crops, forests, and creates visibility concerns. The CAAQS were developed to protect the health of the most sensitive groups. The definition of an air quality standard is the maximum amount of a pollutant averaged over a specified period that can be present in outdoor air without any harmful effects on people or the environment. In 1959, legislation was enacted in California requiring the state Department of Public Health to establish air quality standards and necessary controls for motor vehicle emissions.

The CAAQS are often more stringent than national standards (NAAQS). The pollutants are as follows: particulate matter (PM2.5 and PM10), O3, NO2, sulfate, CO, SO2, visibility reducing particles (haze), Pb, hydrogen sulfide (H2S), and vinyl chloride. California law continues to mandate CAAQS, although the attainment of the NAAQS has precedence due to federal penalties for failure to meet federal attainment deadlines. California law does not require that CAAQS be met by specified dates as in the case with NAAQS, rather it requires incremental progress towards attainment (CARB 2025a).

Air Toxics Hot Spots Program
The Air Toxics “Hot Spots” Information and Assessment Act (Assembly Bill [AB] 2588), established in 1987, is a California program designed to identify and mitigate localized sources of toxic air pollution. The program mandates that facilities emitting significant amounts of TACs report their emissions to relevant air districts. These districts then assess the health risks associated with these emissions, focusing on areas with elevated cancer risk or potential for other adverse health effects. If significant risks are identified, the facility is designated a “hot spot” and is required to notify the surrounding community. This notification empowers the public with information about potential health risks and allows them to engage in decision-making processes regarding risk reduction. In addition, facilities identified as hot spots must conduct further risk assessments and develop plans to reduce their emissions to acceptable levels. This multi-step process aims to protect public health by identifying and mitigating sources of toxic air pollution, promoting transparency, and encouraging community involvement in air quality management (CARB 2025b).

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-5 Criteria Air Pollutants
CARB has established CAAQS for sulfates, hydrogen sulfide, vinyl chloride, visibility-reducing particulate matter, and the above-mentioned criteria air pollutants. In most cases the CAAQS are more stringent than the NAAQS.

Differences in the standards are generally explained by the health effects studies considered during the standardsetting process and the interpretation of the studies. In addition, the CAAQS incorporate a margin of safety to protect sensitive individuals.

The CCAA requires that all local air districts in the state endeavor to attain and maintain the CAAQS by the earliest date practical. The CCAA specifies that local air districts should focus particular attention on reducing the emissions from transportation and area-wide emission sources. The CCAA also provides air districts with the authority to regulate indirect sources.

Toxic Air Contaminants
TACs in California are regulated primarily through the Tanner Air Toxics Act (AB 1807, Chapter 1047, Statutes of 1983) and the Air Toxics Hot Spots Information and Assessment Act of 1987 (AB 2588, Chapter 1252, Statutes of 1987). AB 1807 sets forth a formal procedure for CARB to designate substances as TACs. Research, public participation, and scientific peer review are required before CARB can designate a substance as a TAC. To date, CARB has identified more than 21 TACs and adopted EPA’s list of HAPs as TACs. In 1998, particulate matter exhaust from diesel engines (diesel PM) was added to CARB’s list of TACs.

After a TAC is identified, CARB then adopts an airborne toxics control measure for sources that emit that particular TAC.

If a threshold exists for a substance at which there is no toxic effect, the control measure must reduce exposure below that threshold. If no safe threshold exists, the measure must incorporate the BACT for toxics to minimize emissions.

The Hot Spots Act requires that existing facilities that emit toxic substances above a specified level prepare an inventory of toxic emissions, prepare a risk assessment if emissions are significant, notify the public of significant risk levels, and prepare and implement risk reduction measures.

CARB has adopted diesel exhaust control measures and more stringent emissions standards for various transportationrelated mobile sources of emissions, including transit buses, and off-road diesel equipment (e.g., tractors, generators).

Over time, the replacement of older vehicles will result in a vehicle fleet that produces substantially lower levels of TACs than under current conditions. Mobile-source emissions of TACs (e.g., benzene, 1-3-butadiene, diesel PM) have been reduced significantly over the last decade and will be reduced further in California through a progression of regulatory measures (e.g., Low Emission Vehicle/Clean Fuels and Phase II reformulated gasoline regulations) and control technologies. With the implementation of CARB’s Risk Reduction Plan and other regulatory programs, it is estimated that emissions of diesel PM will be less than half of those in 2010 by 2035 (CARB 2025c). Adopted regulations are also expected to continue to reduce formaldehyde emissions emitted by cars and light-duty trucks. As emissions are reduced, it is expected that risks associated with exposure to the emissions will also be reduced.

Senate Bill 1383
Senate Bill (SB) 1383 (Chapter 249, Statutes of 2016) required CARB to approve and implement a plan by January 2018 to achieve reductions of short-lived climate pollutants such as methane, and tropospheric ozone. SB 1383 also sets a target for reduction of methane emissions to 40 percent below 2013 levels by 2030. Pursuant to SB 605 and SB 1383, CARB subsequently developed the Short-Lived Climate Pollutant Reduction Strategy, adopted in March 2017. As part of this strategy, the California Department of Resources Recycling and Recovery (CalRecycle), in consultation with CARB, was required to develop regulations to reduce statewide disposal of organic waste by 50 percent of 2014 levels by 2020, and by 75 percent of 2014 levels by 2025, including recovery of at least 20 percent of edible food for human consumption. CalRecycle adopted these regulations in 2017, and they became effective on January 1, 2022. The proposed project is designed to address SB 1383 goals.

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3.3-6 Roseville Environmental Utilities Operations Center Project Draft EIR California Department of Resources, Recycling, and Recovery According to Title 14 California Code of Regulations (CCR) Section 17863.4 all compostable material handling operations and facilities in California are required to “prepare, implement, and maintain” a site-specific Odor Impact Minimization Plan (OIMP). OIMPs must provide guidance to on-site operations personnel by describing, at a minimum, the following items:
 an odor monitoring and data collection protocol for on-site odor sources, including the proximity of possible odor receptors and a method for assessing odor impacts at the locations of the possible odor receptors;  a description of meteorological conditions affecting the migration of odors and/or transport of odor-causing material off-site, including seasonal variations that affect wind velocity and direction;  a complaint response and recordkeeping protocol;
 a description of design considerations and/or projected ranges of optimal operation to be employed in minimizing odor, including method and degree of aeration, moisture content of materials, feedstock characteristics, airborne emission production, process water distribution, pad and site drainage and permeability, equipment reliability, personnel training, weather event impacts, utility service interruptions, and site-specific concerns as applicable; and
 a description of operating procedures for minimizing odor, including aeration, moisture management, feedstock quality, drainage controls, pad maintenance, wastewater pond controls, storage practices (e.g., storage time and pile geometry), contingency plans (i.e., equipment, water, power, and personnel), biofiltration, and tarping as applicable.

Odor regulation and enforcement at compost facilities are regulated by CalRecycle.

LOCAL
Sacramento Area Council of Governments
The Sacramento Area Council of Governments (SACOG) is an association that includes the Counties of El Dorado, Placer, Sacramento, Sutter, Yolo, and Yuba. SACOG is responsible for preparing and updating the metropolitan transportation plan/sustainable communities strategy (MTP/SCS). The MTP/SCS is a regional vision to accommodate long-term growth needs of the Sacramento region and has been prepared and plays a critical role in supporting the State’s climate efforts as well as local objectives to provide clean air for residents, as air quality can be directly affected by the type and density of land use change and population growth in urban and rural areas. SACOG completed and adopted the 2025 MTP/SCS in November 2025, which aims to achieve various federal, state, regional, and local policy objectives related to development, transportation, and emission reductions while considering financial, growth, and regulatory constraints.

Placer County Air Pollution Control District
The project site lies within the Placer County portion of the Sacramento Valley Air Basin (SVAB), which is under the jurisdiction of the PCAPCD. PCAPCD includes portions of three different air basins (i.e., Sacramento Valley, Mountain, and the Lake Tahoe Air Basins). PCAPCD is primarily responsible for developing and implementing rules and regulations for attainment of NAAQS and CAAQS, developing air quality management plans, permitting new or modified sources, and adopting and enforcing air pollution regulations within the Basin. The ability of PCAPCD to control emissions (including criteria pollutants, TACs, and greenhouse gas emissions [GHGs]) is provided primarily through permitting, but also through its role as a CEQA lead, responsible, or commenting agency, the establishment of CEQA thresholds, and the development of analytical requirements and guidance for CEQA documents.

Criteria Air Pollutants
PCAPCD attains and maintains air quality conditions in Placer County through a comprehensive program of planning, regulation, enforcement, technical innovation, and promotion of the understanding of air quality issues. The clean air strategy of PCAPCD includes the preparation of plans and programs for the attainment of ambient air quality standards, adoption and enforcement of rules and regulations, and issuance of permits for stationary sources. PCAPCD

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-7 also inspects stationary sources, responds to citizen complaints, monitors ambient air quality and meteorological conditions, and implements other programs and regulations required by the CAA, CAA Amendments, and CCAA.

All projects in Placer County are subject to PCACPD’s adopted rules and regulations in effect at the time of construction. Specific rules applicable to the project may include but are not limited to the following:
 PCAPCD Rule 202 Visible Emissions: Requires that opacity emissions from any emission source not exceed 20 percent for more than 3 minutes in any one hour.
 PCAPCD Rule 205 Nuisance: A person shall not discharge from any source whatsoever such quantities of air contaminants or other material which cause injury, detriment, nuisance or annoyance to any considerable number of persons or to the public, or which endanger the comfort, repose, health or safety of any such persons or the public, or which cause to have a natural tendency to cause injury or damage to business or property.  PCAPCD Rule 207 Particulate Matter:
 A. For the Sacramento Valley Air Basin and the Mountain Counties Air Basin portions of the Placer County Air Pollution Control District a person shall not release or discharge into the atmosphere from any source or single processing unit, exclusive of sources emitting combustion contaminants only, particulate matter emissions in excess of: 0.1 grains per cubic foot of gas at District standard conditions.  PCAPCD Rule 210 Specific Contaminants
 A. A person shall not discharge into the atmosphere from any source of emissions whatsoever, any one or more of the following contaminants, in any state or combination, therefore exceeding in concentration at point of discharge:
• 1. Sulfur compounds, calculated as sulfur dioxide (SO2):
− a. 0.2 percent by volume for the Sacramento Valley and Mountain Counties Air Basin portions of the Placer County Air Pollution Control District.
• 2. Combustion Contaminants: Wood fired boilers and incinerators in the Sacramento Valley and Mountain Counties Air Basin portions of the Placer County Air Pollution Control District: 0.2 grains per cubic foot of gas calculated to 12 percent carbon dioxide (CO2) at standard conditions.  PCAPCD Rule 217 Cutback and Emulsified Asphalt Paving Materials  1.1.1 A person shall not discharge to the atmosphere volatile organic compounds (VOCs) caused by the use or manufacture of Cutback or Emulsified asphalts for paving, road construction, or road maintenance, unless such manufacture or use complies with the provisions of this Rule.  PCAPCD Rule 218 Application of Architectural Coatings: To limit the quantity of volatile organic compounds in architectural coatings supplied, sold, offered for sale, applied, solicited for application, or manufactured for use within the District.
 PCAPCD Rule 228 Fugitive Dust:
 101 Purpose: To reduce the amount of particulate matter entrained in the ambient air, or discharged into the ambient air, as a result of anthropogenic (man-made) fugitive dust sources by requiring actions to prevent, reduce, or mitigate fugitive dust emissions.
 104 Partial Exemptions
• 104.2 Permitted Facilities: The provisions of Section 400, with the exception of Section 405, Reasonable Precautions, shall not apply to any facility permitted by the District in accordance with Rule 501, General Permit Requirements.
• 104.3 Permitted Facilities with Non-Fugitive Emissions: The provisions of Section 303 shall not apply to any facility having non-fugitive particulate matter emissions that are permitted by the District in accordance with Rule 501, General Permit Requirements.

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3.3-8 Roseville Environmental Utilities Operations Center Project Draft EIR  401 Minimum Dust Control Requirements: The following dust mitigation measures are to be initiated at the start and maintained throughout the duration of the construction or grading activity, including any construction or grading for road construction or maintenance. • 401.1 Unpaved areas subject to vehicle traffic must be stabilized by being kept wet, treated with a chemical dust suppressant, or covered. In geographic ultramafic rock units, or when naturally-occurring asbestos, ultramafic rock, or serpentine is to be disturbed, the cover material shall contain less than 0.25 percent asbestos as determined using the bulk sampling method for asbestos in Section 502. • 401.2 The speed of any vehicles and equipment traveling across unpaved areas must be no more than 15 miles per hour unless the road surface and surrounding area is sufficiently stabilized to prevent vehicles and equipment traveling more than 15 miles per hour from emitting dust exceeding Ringelmann 2 or visible emissions from crossing the project boundary line. • 401.3 Storage piles and disturbed areas not subject to vehicular traffic must be stabilized by being kept wet, treated with a chemical dust suppressant, or covered when material is not being added to or removed from the pile.
• 401.4 Prior to any ground disturbance, including grading, excavating, and land clearing, sufficient water must be applied to the area to be disturbed to prevent emitting dust exceeding Ringelmann 2 and to minimize visible emissions from crossing the boundary line. • 401.5 Construction vehicles leaving the site shall be cleaned to prevent dust, silt, mud, and dirt from being released or tracked offsite.
• 401.6 When wind speeds are high enough to result in dust emissions crossing the boundary line, despite the application of dust mitigation measures, grading, and earthmoving operations shall be suspended. • 401.7 No trucks are allowed to transport excavated material off-site unless the trucks are maintained such that no spillage can occur from holes or other openings in cargo compartments and loads are either:
− 401.7.1 Covered with tarps; or
− 401.7.2 Wetted and loaded such that the material does not touch the front, back, or sides of the cargo compartment at any point less than six inches from the top and that no point of the load extends above the top of the cargo compartment.
• 401.8 In geographic ultramafic rock units, or when naturally-occurring asbestos, ultramafic rock, or serpentine is disturbed, all equipment must be washed down before moving from the property onto a paved public road.
• 401.9 In geographic ultramafic rock units, or when naturally-occurring asbestos, ultramafic rock, or serpentine is disturbed, upon completion of the project disturbed surfaces shall be stabilized using one or more of the following methods:
− 401.9.1 Establishment of a vegetative cover;
− 401.9.2 Placement of at least one (1.0) foot of non-asbestos-containing material; − 401.9.3 Paving;
− 401.9.4 Any other measure deemed sufficient to prevent wind speeds of ten (10) miles per hour or greater from causing visible dust emissions.

PCAPCD is located within the federally designated Sacramento Federal Ozone Nonattainment Area (SFNA) for air quality planning purposes. This is primarily because emissions generated within Placer County may affect the nearby Sacramento-Metropolitan Area. As a part of the SFNA, PCAPCD works with Sacramento Metropolitan Air Quality Management District (SMAQMD) and the other local air districts within the Sacramento area to develop a regional air quality management plan under CAA requirements. This management plan is called a SIP which describes and demonstrates how Placer County, as well as the Sacramento nonattainment area, would attain the required federal 8-

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-9 hour ozone standard by the required attainment deadline. At a public meeting held on October 26, 2023, CARB voted to approve the Sacramento Regional 70 parts per billion (ppb) 8-Hour Ozone Attainment and Reasonable Further Progress Plan. The Sacramento Regional 70 ppb 8-Hour Ozone Attainment and Reasonable Further Progress Plan was prepared by the five local air districts of the SFNA, including PCAPCD, with the support of CARB. This plan is an Air Quality Attainment Plan (AQAP) that is applicable to development in the project area. One of the proposed mitigation strategies in the SIP is to recommend and implement mitigation measures through the review of land use projects at the local level (PCAPCD 2017). PCAPCD also adopted the 2014 Reasonably Available Control Technology (RACT) State Implementation Plan Analysis and Federal Negative Declarations for 16 Control Technique Source Categories. CARB submitted the 2014 RACT SIP to the EPA as a revision to the California SIP.

Toxic Air Contaminants
At the local level, PCAPCD may adopt and enforce CARB’s airborne toxic control measures or else adopt its own, equally as stringent measures. Under PCAPCD Rule 501 (“Permit Requirements”), PCAPCD Rule 502 (“New Source Review”), and PCAPCD Rule 507 (“Federal Operating Permit”), all sources that possess the potential to emit TACs are required to obtain permits from PCAPCD. PCAPCD may grant permits to these operations if they are constructed and operated in accordance with applicable regulations, including new source review standards and air toxics control measures. PCAPCD limits emissions and public exposure to TACs through a number of programs.

Sources that require a permit are analyzed by PCAPCD (e.g., health risk assessment) based on their potential to emit TACs that would expose receptors to substantial health risks. If it is determined that the project would emit TACs in excess of PCAPCD’s standard of significance for TACs (identified below), then the source would have to implement BACT for TACs to reduce emissions. If a source cannot reduce the risk below the threshold of significance even after the BACT has been implemented, PCAPCD will deny the permit required by the source. This helps to prevent new problems and reduces emissions from existing older sources by requiring them to apply new TAC-reduction technology when being retrofitted.

City of Roseville General Plan 2035
The Air Quality and Climate Change Element of the City of Roseville General Plan 2035 (General Plan) contains goals and policies that pertain to criteria air pollutant emissions, TACs, and odors (City of Roseville 2020). Key policies, and implementation measures that are applicable to the project include the following:

Air Quality Policies
 Policy AQ1.1: Cooperate with other agencies to develop a consistent and an effective approach to reducing air pollution.
 Policy AQ1.2: Work with the Placer County Air Pollution Control District to monitor air pollutants of concern on a continuous basis, and support Air District efforts to minimize emissions from stationary sources.  Policy AQ1.3 Projects that could generate or expose sensitive uses to substantial air pollutant concentrations should incorporate strategies to reduce exposure to such emissions using measures recommended by the Placer County Air Pollution Control District and other applicable, feasible strategies, as needed, to avoid significant air quality impacts.
 Policy AQ1.4 As part of the development review process, develop mitigation measures to minimize stationary and area source emissions.
 Policy AQ1.13: Identify feasible strategies to reduce transportation emissions from new projects and existing development within the Planning Area.
 Policy AQ1.15: Promote and incentivize low-emissions vehicles and associated charging infrastructure, and pursue funding from state programs and other sources to facilitate local purchase and use of electric vehicles.  Policy AQ1.17: Conserve energy and reduce air pollutant emissions by encouraging energy efficient building designs and transportation systems and promoting energy efficiency retrofits of existing structures.  Policy AQ1.19: Encourage energy efficiency by identifying potential cost savings, resource, and health benefits.

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3.3-10 Roseville Environmental Utilities Operations Center Project Draft EIR  Policy AQ1.21 Protect City residents from the risks involved in the transport, distribution, storage, use, and disposal of hazardous materials, and coordinate with other agencies and organizations to reduce existing sources of health risk.

General Plan Implementation Measures
Appendix A of the General Plan identifies the General Plan’s implementation measures, which are proactive activities designed to implement General Plan policies. Implementation measures are designated as ongoing or proposed (i.e., not yet implemented). The following may apply to the project:

Air Quality and Climate Change Mitigation Strategies - Area and Stationary Sources (Ongoing in General Plan) Require area and stationary source projects that generate significant amounts of air pollutants to incorporate air quality mitigation in their design, including the use of best available control technology for stationary industrial sources; clean fuel sources for heating and cooling; clean fuel technology at fueling stations; and other strategies, in consultation with PCAPCD.

Air Quality and Climate Change Mitigation Strategies - Land Use (Ongoing in General Plan) Encourage development to be located and designed to minimize greenhouse gas and air pollutant emissions and avoid exposure to substantial pollutant concentrations by doing the following:
 Locate point sources, such as manufacturing and extracting facilities, in areas designated for industrial development and separated from residential areas and other sensitive receptors (e.g., homes, schools, and hospitals);  Provide separation between sources of substantial air pollutant emissions and sensitive receptors and/or provide landscaping using plant species that are shown to reduce pollutant exposure; and  Provide for mixed-use and transit-supportive development that reduces the length and frequency of vehicle trips or reduces the need for vehicle trips by providing practical pedestrian, bicycle, and transit options.

Toxic Air Contaminants (Proposed in General Plan)
 The City shall require, as part of plans for development within the Planning Area, the implementation of ARB’s Air Quality and Land Use Handbook: A Community Health Perspective guidance concerning land use compatibility and recommended setback distances with regard to sources of TAC emissions and sensitive land uses, or related guidance as it may be updated in the future.
 As an alternative to these buffer distances, proposed sensitive receptors, uses that involve substantial truck trips, and large gas stations may provide a site-specific health risk assessment, using methods consistent with applicable guidance from the Office of Environmental Health Hazard Assessment, with mitigation, if necessary, to demonstrate compliance with applicable PCAPCD-recommended health risk thresholds. When health risk impacts exceed PCAPCD-recommended thresholds, feasible on-site mitigation measures to reduce TAC exposure shall be implemented to mitigate health risk impacts below PCAPCD-recommended thresholds. On-site measures could include but are not limited to providing enhanced filtration systems (e.g., MERV 13 or greater) for near-by sensitive receptor buildings, use of solid barriers to pollution, and vegetation to reduce pollutant concentrations, changes to the TAC emission source’s operation (e.g. technology or management practices that reduce harmful emissions at the Rail Yard), and positioning of exhaust and intake for ventilation systems to minimize exposure, among others.  Installation of solid barriers, particularly in the downwind direction. Note that consideration of this strategy should also weigh the negative effect of dividing neighborhoods and obscuring sightlines.  Installation of vegetation for pollutant dispersion; maximum benefit of this strategy is typically seen when combined with solid barriers.
 Installation of indoor high-efficiency filtration systems and devices to remove pollutants from the air. If this strategy is selected, a plan for ongoing operation and maintenance of the systems must also be developed to ensure long-term efficiency is achieved as intended by the system.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-11

3.3.2 Environmental Setting
The project site is located in the City of Roseville within western Placer County, California, which is located within the SVAB. The SVAB also includes all of Butte, Colusa, Glenn, Sacramento, Shasta, Sutter, Tehama, Yolo, and Yuba counties and the eastern portion of Solano County.

The ambient concentrations of air pollutant emissions are determined by the amount of emissions released by the sources of air pollutants and the atmosphere’s ability to transport and dilute such emissions. Natural factors that affect transport and dilution include terrain, wind, atmospheric stability, and sunlight. Therefore, existing air quality conditions in the area are determined by such natural factors as topography, meteorology, and climate, in addition to the amount of emissions released by existing air pollutant sources, as discussed separately below.

The nearest existing sensitive receptors to the project site are residences along Phillip Road, approximately 235 feet south of the project site; residences along South Brewer Road, located approximately 0.25 miles southwest and west of the western project boundary; and residences approximately 1.7 miles east of the eastern project boundary.

AIR QUALITY AND AIR POLLUTANTS: A COMPREHENSIVE OVERVIEW Air quality, the condition of the air we breathe, is a critical aspect of environmental and public health. Air pollutants, substances present in the air at concentrations that can harm living organisms or the environment, originate from both natural and human-made sources. Natural sources include volcanic eruptions, dust storms, and wildfires, while human activities like industrial processes, transportation, and agriculture contribute significantly to air pollution.

Common air pollutants include particulate matter (PM), ground-level ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, and lead. PM, tiny particles suspended in the air, poses a significant health risk as it can penetrate deep into the lungs and even enter the bloodstream. Ground-level ozone, formed from reactions between nitrogen oxides and volatile organic compounds in the presence of sunlight, is a major component of smog and can harm respiratory health. Other pollutants like carbon monoxide, sulfur dioxide, and nitrogen dioxide also contribute to respiratory and cardiovascular problems (WHO n.d.).

Air pollution arises from a combination of both natural and anthropogenic sources. While natural events like volcanic eruptions, dust storms, wildfires, and sea salt contribute, human activities are the primary drivers, especially in populated and industrialized areas. Transportation, fueled largely by fossil fuels, is a major culprit, releasing nitrogen oxides, carbon monoxide, particulate matter, and volatile organic compounds into the air. Industrial processes, from power generation to manufacturing, emit a cocktail of pollutants, including sulfur dioxide, nitrogen oxides, particulate matter, and hazardous air pollutants. Agriculture, with its livestock and fertilizer use, adds ammonia, methane, and other pollutants to the mix. Even our homes and businesses contribute, with the burning of fossil fuels for heating and cooking, alongside the use of solvents and chemicals. Waste management, through landfills and incineration, releases methane, particulate matter, and other harmful substances. Recognizing this diverse array of sources is essential for devising effective strategies to combat air pollution and safeguard both human health and the environment.

Air quality is a localized concern, as pollutants tend to concentrate near their sources. However, some pollutants, particularly particulate matter and ozone, can travel long distances, impacting air quality in areas far from their origin.

Air pollution has a significant impact on human health, contributing to respiratory diseases, cardiovascular problems, cancer, and other adverse health effects. It also harms the environment, damaging crops, forests, and aquatic ecosystems. Efforts to improve air quality involve a combination of regulatory measures, technological advancements, and individual actions. Regulations like the Clean Air Act set air quality standards and require pollution control measures for various sources. Technological advancements in cleaner fuels, energy-efficient vehicles, and industrial processes also contribute to reducing air pollution. Individual actions like driving less, conserving energy, and supporting policies promoting clean air can also make a difference. Understanding air quality and its impact on health and the environment is crucial for making informed decisions and taking action to protect ourselves and the environment.

Air Quality Ascent
City of Roseville

3.3-12 Roseville Environmental Utilities Operations Center Project Draft EIR

CLIMATE, METEOROLOGY, AND TOPOGRAPHY
The SVAB is a relatively flat area bordered by the north Coast Ranges to the west and the northern Sierra Nevada to the east. Air flows into SVAB through the Carquinez Strait, the only breach in the western mountain barrier, and moves across the Sacramento River–San Joaquin River Delta (Delta) from the San Francisco Bay area. The Mediterranean climate type of SVAB is characterized by hot, dry summers and cool, rainy winters. During the summer, daily temperatures range from 50 degrees Fahrenheit (°F) to more than 100°F. The inland location and surrounding mountains shelter the area from much of the ocean breezes that keep the coastal regions moderate in temperature.

Most precipitation in the area results from air masses that move in from the Pacific Ocean, usually from the west or northwest, during the winter months. More than half the total annual precipitation falls during the winter rainy season (November through February); the average winter temperature is a moderate 49°F. Another characteristic of SVAB winters are periods of dense and persistent low-level fog, which are most prevalent between storms. The prevailing winds are moderate in speed and vary from moisture-laden breezes from the south to dry land flows from the north.

The mountains surrounding the SVAB create a barrier to airflow, which leads to the entrapment of air pollutants when meteorological conditions are unfavorable for transport and dilution. The highest frequency of poor air movement occurs in the fall and winter when high-pressure cells are often present over the SVAB. The lack of surface wind during these periods, combined with the reduced vertical flow caused by a decline in surface heating, reduces the influx of air and leads to the concentration of air pollutants under stable metrological conditions. Surface concentrations of air pollutant emissions are highest when these conditions occur in combination with agricultural burning activities or with temperature inversions, which hamper dispersion by creating a ceiling over the area and trapping air pollutants near the ground.

May through October is ozone season in the SVAB. This period is characterized by poor air movement in the mornings with the arrival of the Delta breeze from the southwest in the afternoons. In addition, longer daylight hours provide a plentiful amount of sunlight to fuel photochemical reactions between reactive organic gases (ROG) and NOx, which result in ozone formation. Typically, the Delta breeze transports air pollutants northward out of SVAB; however, a phenomenon known as the Schultz Eddy prevents this from occurring during approximately half of the time from July to September. The Schultz Eddy phenomenon causes the wind to shift southward and blow air pollutants back into the SVAB. This phenomenon exacerbates the concentration of air pollutant emissions in the area and contributes to the area violating the ambient air quality standards.

The local meteorology of the project area and surrounding area is represented by measurements recorded at the Western Regional Climate Center (WRCC) Rocklin station. The normal annual precipitation is approximately 23 inches.

January temperatures range from a normal minimum of 35°F to a normal maximum of 54°F. July temperatures range from a normal minimum of 58°F to a normal maximum of 97°F (WRCC 2025). The predominant wind direction is from the south (WRCC 2025).

CRITERIA AIR POLLUTANTS
Concentrations of criteria air pollutants are used to indicate the quality of the ambient air. A brief description of key criteria air pollutants in the SVAB is provided below. Emission source types and health effects are summarized in Table 3.3-2. Placer County’s attainment status for the CAAQS and the NAAQS are shown in Table 3.3-3.

Ozone
Ozone is a photochemical oxidant (a substance whose oxygen combines chemically with another substance in the presence of sunlight) and the primary component of smog. Ozone is not directly emitted into the air but is formed through complex chemical reactions between precursor emissions of ROG and NOX in the presence of sunlight. ROG are volatile organic compounds that are photochemically reactive. ROG emissions result primarily from incomplete combustion and the evaporation of chemical solvents and fuels. NOX are a group of gaseous compounds of nitrogen and oxygen that result from the combustion of fuels.

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City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-13 Emissions of the ozone precursors ROG and NOX have decreased over the past several years because of more stringent motor vehicle standards and cleaner-burning fuels. The Sacramento Regional 70 ppb 8-Hour Ozone Attainment and Reasonable Further Progress Plan identified that ROG and NOX concentrations at two study sites in the area trended downward between 2000 and 2021 despite year-to-year variations and are projected to continue decreasing through 2032 (EDCAQMD et al. 2023).

Nitrogen Dioxide
NO2 is a brownish, highly reactive gas that is present in all urban environments. The major human-made sources of NO2 are combustion devices, such as boilers, gas turbines, and mobile and stationary reciprocating internal combustion engines. Combustion devices emit primarily nitric oxide (NO), which reacts through oxidation in the atmosphere to form NO2. The combined emissions of NO and NO2 are referred to as NOX and are reported as equivalent NO2. Because NO2 is formed and depleted by reactions associated with photochemical smog (ozone), the NO2 concentration in a particular geographical area may not be representative of the local sources of NOX emissions (EPA 2024).

Particulate Matter
As discussed above, particulate matter with an aerodynamic diameter of 10 micrometers or less is referred to as PM10.

PM10 consists of particulate matter emitted directly into the air, such as fugitive dust, soot, and smoke from mobile and stationary sources, construction operations, fires and natural windblown dust, as well as particulate matter formed in the atmosphere by reaction of gaseous precursors (CARB 2013). PM10 emissions in the SVAB are dominated by emissions from area sources, primarily fugitive dust from vehicle travel on unpaved and paved roads, farming operations, construction and demolition, and particles from residential fuel combustion. Direct emissions of PM10 are projected to remain relatively constant through 2035. Direct emissions of PM2.5 have steadily declined in the SVAB between 2000 and 2010 and then are projected to increase very slightly through 2035. Emissions of PM2.5 in the SVAB are dominated by the same sources as emissions of PM10 (CARB 2013).

Table 3.3-2 Sources and Health Effects of Criteria Air Pollutants Pollutant Sources Acute1 Health Effects Chronic2 Health Effects Ozone Secondary pollutant resulting from reaction of ROG and NOX in presence of sunlight. ROG emissions
result from incomplete combustion and evaporation
of chemical solvents and fuels; NOX results from the
combustion of fuels
increased respiration and
pulmonary resistance; cough, pain,
shortness of breath, lung
inflammation
permeability of
respiratory epithelia,
possibility of
permanent lung
impairment
Carbon monoxide (CO) Incomplete combustion of fuels; motor vehicle exhaust
headache, dizziness, fatigue,
nausea, vomiting, death
permanent heart and
brain damage
Nitrogen dioxide (NO2) combustion devices; e.g., boilers, gas turbines, and mobile and stationary reciprocating internal
combustion engines
coughing, difficulty breathing,
vomiting, headache, eye irritation,
chemical pneumonitis or
pulmonary edema; breathing
abnormalities, cough, cyanosis,
chest pain, rapid heartbeat, death
chronic bronchitis,
decreased lung
function
Sulfur dioxide (SO2) coal and oil combustion, steel mills, refineries, and pulp and paper mills
Irritation of upper respiratory tract,
increased asthma symptoms
Insufficient evidence
linking SO2 exposure to
chronic health impacts
Respirable particulate matter
(PM10),
Fine particulate matter
(PM2.5)
fugitive dust, soot, smoke, mobile and stationary
sources, construction, fires and natural windblown
dust, and formation in the atmosphere by
condensation and/or transformation of SO2 and ROG
breathing and respiratory
symptoms, aggravation of existing
respiratory and cardiovascular
diseases, premature death
alterations to the
immune system,
carcinogenesis
Lead metal processing reproductive/ developmental
effects (fetuses and children)
numerous effects
including neurological,
endocrine, and
cardiovascular effects

Air Quality Ascent
City of Roseville

3.3-14 Roseville Environmental Utilities Operations Center Project Draft EIR Notes: NOX = oxides of nitrogen; ROG = reactive organic gases. 1 “Acute health effects” refers to immediate illnesses caused by short-term exposures to criteria air pollutants at fairly high concentrations. An example of an acute health effect includes fatality resulting from short-term exposure to carbon monoxide levels in excess of 1,200 parts per million. 2 “Chronic health effects” refers to cumulative effects of long-term exposures to criteria air pollutants, usually at lower, ambient concentrations. An example of a chronic health effect includes the development of cancer from prolonged exposure to particulate matter at concentrations above the national ambient air quality standards.

Source: EPA 2025c.

MONITORING STATION DATA AND ATTAINMENT DESIGNATIONS
Criteria air pollutant concentrations are measured at several monitoring stations in the SVAB. The Sacramento International Airport station is located approximately 9 miles southwest of the project site and is the closest monitoring station to the project site with recent data for ozone, PM10, and PM2.5. In general, the local ambient air quality measurements from this station are representative of the air quality near the project given its similar meteorological conditions and urban surroundings.

Both CARB and EPA use this type of monitoring data to designate areas according to their attainment status in accordance with ambient air quality standards for criteria air pollutants. The purpose of these designations is to identify those areas with air quality problems and thereby initiate planning efforts for improvement. The three basic designation categories are “nonattainment,” “attainment,” and “unclassified.” “Nonattainment” means that an area does not attain State or federal ambient air quality standards for a given pollutant, while “attainment” means that an area either attains or exceeds State or federal ambient air quality standards. “Unclassified” is used in an area that cannot be classified on the basis of available information as meeting or not meeting the standards. In addition, the California designations include a subcategory of the nonattainment designation, called “nonattainment-transitional.” The nonattainmenttransitional designation is given to nonattainment areas that are progressing and nearing attainment. Attainment designations in Placer County are shown in Table 3.3-3 for each criteria air pollutant. Key pollutants for which Placer County is in nonattainment include ozone (California and National), PM10 (California), and PM2.5 (National).

Table 3.3-3 Attainment Status Designations for Placer County Pollutant National Ambient Air Quality Standard California Ambient Air Quality Standard Ozone Revoked in 2005 (1-hour)1 Nonattainment (1-hour) Classification-Serious2 Attainment (8-hour)3 Nonattainment (8-hour)
Nonattainment (8-hour)4 Classification=Severe Nonattainment (8-hour) Respirable particulate matter (PM10) Attainment (24-hour) Nonattainment (24-hour) Attainment (24-hour) Nonattainment (Annual)
Fine particulate matter (PM2.5) Nonattainment (24-hour) (No State Standard for 24-Hour) Attainment (Annual) Attainment (Annual)
Carbon monoxide (CO) Attainment (1-hour) Attainment (1-hour) Attainment (8-hour) Attainment (8-hour)
Nitrogen dioxide (NO2) Attainment (1-hour) Attainment (1-hour) Attainment (Annual) Attainment (Annual)
Sulfur dioxide (SO2)
5 (Attainment Pending) (1-Hour) Attainment (1-hour)
(Attainment Pending) (1-Hour) Attainment (24-hour)
Lead (Particulate) Attainment (3-month rolling avg.) Attainment (30-day average) Hydrogen Sulfide No Federal Standard Unclassified (1-hour) Sulfates No Federal Standard Attainment (24-hour)
Visibly Reducing Particles No Federal Standard Unclassified (8-hour) Vinyl Chloride No Federal Standard Unclassified (24-hour)

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City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-15 Notes:
1 Air Quality meets federal 1-hour Ozone standard (77 FR 64036). EPA revoked this standard, but some associated requirements still apply. 2 Per Health and Safety Code Section 40921.5(c), the classification is based on 1989 – 1991 data, and therefore does not change. 3 2008 Standard.
4 2015 Standard.
5 2010 Standard.

Sources: EDCAQMD et al. 2023; EPA 2025d.

In August 2025, EPA finalized their determination that the Sacramento Metro area attained the 2008 8-hour ozone NAAQ by its December 31, 2024, attainment date as well as a determination that the requirement for the State to have contingency measures for reasonable further progress and attainment for the 2008 ozone NAAQS no longer applies to this area (EPA 2025d). The Sacramento Regional 2015 8-hour Ozone Attainment and Reasonable Further Progress Plan was prepared to meet the requirements of the federal CAA for the 2015 8-hour ozone standard. This Sacramento Ozone SIP demonstrates how the region is going to reduce emissions and attain the 2015 ozone standard no later than August 3, 2033 (EDCAQMD et al. 2023: 1-1). This air quality plan relies on existing control measures and adopted rules, new state and federal regulations, and new local and regional measures to reduce ozone. The project would be required to adhere to all federal, state, and local regulatory measures to comply with the air quality plan.

TOXIC AIR CONTAMINANTS
According to the California Almanac of Emissions and Air Quality (CARB 2013), most of the estimated health risks from TACs can be attributed to relatively few compounds, the most important being diesel PM. Diesel PM differs from other TACs in that it is not a single substance, but rather a complex mixture of hundreds of substances. Although diesel PM is emitted by diesel-fueled internal combustion engines, the composition of emissions varies depending on engine type, operating conditions, fuel composition, lubricating oil, and whether an emissions control system is being used. Unlike the other TACs, no ambient monitoring data are available for diesel PM because no routine measurement method currently exists. However, CARB has made preliminary concentration estimates based on a PM exposure method. This method uses the CARB emissions inventory’s PM10 database, ambient PM10 monitoring data, and the results from several studies to estimate concentrations of diesel PM. In addition to diesel PM, the TACs for which data are available that pose the greatest existing ambient risk in California are benzene, 1,3-butadiene, acetaldehyde, carbon tetrachloride, hexavalent chromium, para-dichlorobenzene, formaldehyde, methylene chloride, and perchloroethylene. Overall, except for levels of para-dichlorobenzene and formaldehyde, levels of TACs have decreased since 1990 (CARB 2013).

ODORS
Odors are generally regarded as an annoyance rather than a health hazard. However, manifestations of a person’s reaction to foul odors can range from psychological (e.g., irritation, anger, or anxiety) to physiological (e.g., circulatory and respiratory effects, nausea, vomiting, and headache). The ability to detect odors varies considerably among the population and overall is quite subjective. Some individuals can smell minute quantities of specific substances; others may not have the same sensitivity but may have sensitivities to odors of other substances. In addition, people may have different reactions to the same odor; an odor that is offensive to one person may be perfectly acceptable to another (e.g., fast food restaurant). It is important to also note that an unfamiliar odor is more easily detected and is more likely to cause complaints than a familiar one. This is because of the phenomenon known as odor fatigue, in which a person can become desensitized to almost any odor and recognition only occurs with an alteration in the intensity. Uses typically associated with the generation of nuisance odors include wastewater treatment plants, chemical manufacturing facilities, sanitary landfills, fiberglass manufacturing facilities, transfer stations, painting/coating operations (e.g., auto body shop), composting facilities, food processing plants, petroleum refineries, rendering plants, asphalt batch plants, and coffee roasters.

Air Quality Ascent
City of Roseville

3.3-16 Roseville Environmental Utilities Operations Center Project Draft EIR

SENSITIVE RECEPTORS
Sensitive receptors are generally considered to include those land uses where exposure to pollutants could result in health-related risks to sensitive individuals, such as children or the elderly. Residential dwellings, schools, hospitals, playgrounds, and similar facilities are of primary concern because of the presence of individuals particularly sensitive to pollutants and/or the potential for increased and prolonged exposure of individuals to pollutants.

Existing sensitive land uses near the project site include residences. The nearest existing sensitive receptors to the project site are residences along Phillip Road, approximately 235 feet south of the project site; residences along South Brewer Road, located approximately 0.25 miles southwest and west of the western project boundary; and residences approximately 1.7 miles east of the eastern project boundary.

3.3.3 Environmental Impacts and Mitigation Measures

METHODOLOGY
Criteria Air Pollutants and Ozone Precursors
Construction and operational emissions of criteria air pollutants and precursors were quantified using calculation sheets, California Emissions Estimator Model (CalEEMod) Version 2022.1.1.21 computer program, and emission factors from CARB’s EMFAC 2025 model and OFFROAD 2025 model. Emission estimates were based on available projectspecific information and model defaults. The detailed methodology used to estimate air pollutant emissions is described below, by project component/emissions source.

Construction
Construction Phasing
Phase 1 activities would involve grading of the entire area and construction of the RRTO Facility (phase 1), EU Services Facility, Equipment Maintenance Facility, Vendor Lease Area, electrical substation, and Philip Road and force main improvements. Phase 2 would involve completion of construction of the RRTO (phase 2) and Future Potential Organics Processing Facility (which could include a potential future organics compost facility and/or biomass gasification facility).

Construction activities would occur between 7:00 a.m. and 7:00 p.m. Monday through Friday. Emissions rates were calculated based on an anticipated construction schedule of 8 hours per day, 5 days per week, over a 7-year active construction period (Phase 1 and Phase 2). Overall construction phasing was used to assign equipment use and vehicle trips to daily activities to derive maximum emissions and total emissions scenarios. Specifically, mass grading of the entire site is anticipated to occur in Phase 1 to allow construction and installation of facilities during future years. Finish grading, installation, and deliveries of building materials would be phased out over time associated with the construction of each individual component. A detailed phasing schedule is provided in Appendix C.

Off-Road Equipment Exhaust
Specific equipment number, types, horsepower, and load factors for each phase of construction were developed based on default equipment lists contained in the CalEEMod, for representative model runs conducted based on the anticipated acreage to be developed. In addition, project-specific information (i.e., cut / fill quantities) were available and used to adjust CalEEMod defaults to account for the anticipated earthwork that would occur. Exhaust emissions were calculated using emissions rates contained in CalEEMod for each piece of equipment, using statewide fleet average emissions rates, default horsepower and usage factors.

On-Road Vehicles Exhaust and Fugitive Dust
On-road vehicles (e.g., heavy-duty trucks, passenger vehicles) would be required for material hauling, delivery, and employee commuting. Exhaust emissions rates were derived from CARB’s EMFAC 2025 model based on the number of truck trips by trip type (e.g., employee commuting, material deliveries and material hauling) anticipated for construction.

Emissions from haul and delivery trucks were estimated using Heavy-Heavy Duty Truck (HHDT) emission factors from EMFAC 2025, a CalEEMod default of 8.8 miles for each one-way vendor trip, 9.8 miles for each one-way demolition waste

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City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-17 hauling, and the anticipated amount of haul and delivery truck trips for each phase of construction. Emissions associated with construction worker commute travel were estimated based on a weighted average of light duty auto (LDA), light duty truck 1 (LDT1), and light duty truck 2 (LDT2) emission rates from EMFAC 2025, similar to the vehicle split used in CalEEMod (e.g., LDA = 25 percent, LDT1 = 50 percent, LDT2 = 25 percent). In addition, CalEEMod model defaults were used for trip lengths (14.3 miles per worker trip), workers per day (60), and vehicle trips per worker per day (2.5).

Fugitive dust (PM10 and PM2.5) emissions were derived using emissions factors contained in EPA’s AP-42 documentation for grading/dozing activities and vehicular travel on paved and unpaved roads. Emissions factors were applied to grading/dozing/scraping activities as well as vehicle miles travelled (VMT) associated with on- and off-road truck travel. Travel distances were derived using default trip lengths in CalEEMod, as described above, and the project site plan/work area for on-site travel. Standard construction dust suppression practices (e.g., watering twice daily) would be implemented during construction and, thus, were assumed for purposes of modeling.

Operations
Operational emissions were estimated for the initial phase operation in the year 2028, Phase 2 in the year 2040, and full operation in the year 2058. Sources of operational emissions would include project site building operation, onsite off-road equipment exhaust, employee vehicle exhaust, and waste pickup and transfer truck exhaust, fuel delivery truck exhaust, fuel station dispensing emissions, fleet service and maintenance chemical use emissions, biomass compost fugitive emissions, and biomass gasification stack emissions. The following text provides a summary of the methodology used to estimate emissions from each source. Comprehensive assumptions and calculation details are presented in Appendix C.

Building Operation
Regarding operations of the RRTO Facility, Vendor Lease Area, EU Services Facility, and Equipment Maintenance Facility, because the buildings would be all-electric, the default CalEEMod natural gas demand was converted to an equivalent electricity demand and combined with the default electricity consumption values.

On-site Equipment
On-site off-road equipment would be used for material movement at the Material Transfer Station and the Potential Future Organics Processing Facility. Project-specific diesel fueled equipment type, number, horsepower, and annual usage were available. Emissions were estimated using CalEEMod emissions factors and default inputs, as described above for construction-related off-road equipment. Other on-site equipment (e.g., material sorting, screening, grinding) would be electric and would not result in direct air pollutant emissions.

On-Road Vehicle Exhaust and Fugitive Dust
On-road vehicles (e.g., waste pickup trucks, waste transfer trucks, fuel delivery truck, and employee commuting vehicles) would be required for daily operation of the facilities. All emissions associated with vehicle use were based on anticipated daily and annual trip numbers available from the traffic study and VMT analysis prepared for the project (Kittelson & Associates 2025).

Similar to construction vehicles, combustion exhaust, paved road and brake and tire wear fugitive dust (PM10 and PM2.5) were estimated using a combination of emission factors and methodologies from CalEEMod and emission factors from CARB’s EMFAC 2025 model based on the number of truck trips projected in year 2028, 2040, and 2058.

Emissions from waste pickup, transfer, and fuel delivery trucks were estimated using EMFAC 2025 emission factors for T7 SWCV Class 8 and Heavy-Heavy Duty Trucks. An average of 14 miles for each one-way waste truck trip were estimated based on traffic analysis data, and 27.2 miles for each one-way fuel delivery were assumed for the refill of two on-site fuel tanks. For modeling purposes, the waste pickup and transfer trucks were assumed to operate from 6:00 a.m. to 3:00 p.m. Monday through Friday, and the fuel delivery truck was predicted to deliver at approximately 11:00 a.m. and 5 p.m., Monday and Wednesday.

Emissions associated with the employee commute travel were estimated based on a weighted average of light duty auto (LDA), light-duty truck 1 (LDT1, and light-duty truck 2 (LDT2) emission rates from EMFAC 2025, similar to the vehicle split

Air Quality Ascent
City of Roseville

3.3-18 Roseville Environmental Utilities Operations Center Project Draft EIR used in CalEEMod (e.g., LDA = 25 percent, LDT1 = 50 percent, LDT2 = 25 percent). The CalEEMod default trip length of 10.9 miles per worker trip was applied to the project.

Toxic Air Contaminants
The level of health risk from exposure to construction- and operations-related diesel PM emissions and numerous other TACs was assessed quantitively by conducting an HRA. The HRA evaluated construction emissions separately, operational emissions separately (under Full Operation), and evaluated a combined construction and operational scenario. To determine pollutant concentrations at specific locations (i.e., receptors), air dispersion modeling was conducted using site-specific parameters (e.g., terrain, meteorological data) for construction activities and operational activities at full operation.

Modeling Approach
Dispersion modeling was conducted using the CARB-approved American Meteorological Society/Environmental Protection Agency Regulatory Model Improvement Committee modeling system (AERMOD) Version 21112, with a unit emission rate of 1 gram per second (g/s) for all modeled sources. This approach was used so that resulting groundlevel concentrations could be multiplied by actual emission rates for various scenarios (e.g., phase-wise construction, full operation). The modeling included all standard regulatory default options, including the use of data from the nearest and most representative meteorological station (i.e., Sacramento International Airport) and local terrain.

Terrain in the project vicinity is generally flat. The methods used to estimate health risks from construction and operation of the proposed project are briefly described below. Detailed model assumptions, inputs and output for the HRA are presented in the HRA memo in Appendix B.

Construction HRA
To represent site locations where construction activities would occur, construction emission sources (e.g., the use of heavy-duty equipment on-site) were modeled as area sources, consistent with PCAPCD’s guidance on conducting HRAs (PCAPCD 2017). Mobile exhaust emissions were represented using line-volume sources.

Construction mass emissions were quantified as described above for criteria air pollutants and ozone precursors. The primary TAC evaluated in the construction HRA was diesel PM, modeled as PM10 exhaust. Emissions rates were calculated based on an anticipated construction schedule of 8 hours per day, 5 days per week, over a 7-year active construction period (Phase 1 and Phase 2).

Operational HRA
The operational HRA evaluated various TACs associated with on-site activities and anticipated sources and diesel PM associated with off-site truck travel. Overall, the approach was similar to that described above, applying unit rates in the air dispersion model and mass emissions for each individual source to the ground level concentration outputs.

Risk estimated were modeled using CARB’s Hotspot Analysis and Reporting Program (HARP) risk tool (HARP2, version 22118) and the most updated Health Database (July 20, 2025). Specific methods by source, are described in greater detail below and the complete HRA methodology, including model input parameters, is included in Appendix B.

Equipment Maintenance Facility
The facility is anticipated to use 50 gallons each of solvent, degreaser, and paint per year at full operation. VOC emissions were estimated assuming the limit quantity of VOC content per PCAPCD rules: 50 grams of VOC per liters of solvent or degreaser (PCAPCD 1998), and 5.7 pounds per gallons of paint (PCAPCD 2003). Emissions sources were modeled as area sources.

Fueling Station
A fueling station would be located between Phillip Road and the Equipment Maintenance Facility area. This fueling area would provide fuels for all the non-EV vehicles envisioned at the site, including gasoline, diesel, and possibly other fuels as appropriate. Fueling station emissions were estimated following CARB’s guide (CARB 2022), for gasoline and diesel, based on City of Roseville fuel consumption data and anticipated facility capacity increase over time. The emissions include bulk transfer emissions, breathing emissions, fueling vapor emissions from fuel tanks of vehicles without Onboard Refueling Vapor Recovery (ORVR) systems, fueling vapor emissions from fill-pipe of ORVR

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-19 vehicles, emissions due to spillage, and emissions through hose permeation. The emissions were estimated using fuel daily throughput (gallons of fuels per day) and CARB emission factors and assumptions (CARB 2022). Emissions sources were modeled as points and volumes.

Diesel Trucks and Equipment
On-site off-road equipment activity was modeled as an area source, and on-road truck emissions were modeled as line-volume sources, consistent with PCAPCD’s HRA guidance. Diesel PM emissions from off-road equipment were estimated using anticipated annual equipment use supplemented with CalEEMod default values. Diesel PM emission rates from on-road trucks were estimated using VMT-based emission factors derived from EMFAC 2025 emission dataset in Placer County and VMT of trucks in the receptor region. Emissions sources were modeled as line-volumes.

Organics Composting
Air pollution emissions from composting would primarily result from the biological decomposition of organic materials (i.e., green and food materials), which could generate VOCs, ammonia, and GHGs. In addition, material handling activities, including offroad equipment transferring from material recover facility to composting site would result in fugitive dust emissions. Baseline emission factors of 3.58 pounds of VOC and 0.78 pounds of ammonia per ton of wet compost represent an uncontrolled (i.e., not actively managed to control air emissions, odors, or leachate) organics windrow composting (SJVAPCD 2023a).

Aerated static pile (ASP) or covered aerated static pile (CASP) systems with biofiltration either through a compost cap, geomembrane cover, or biofilter would be used for composting. ASP or CASP type composting systems represent statewide Best Available Control Technology (BACT) as determined by several local air districts across the state. CASP systems would achieve approximately 80 percent reduction in VOC emissions and approximately 53 percent reduction in ammonia emissions compared to baseline uncontrolled composting emissions (SJVAPCD 2023b). Because the composting system is designed to be ASP or CASP, the BACT reductions were applied to the ammonia and VOC emission estimations. Fugitive dust PM10 emissions are associated with transferring equipment travel on unpaved surfaces, and material handling and sorting. Fugitive dust generated from material handling and sorting activities would primarily consist of particulate matter and is not considered a toxic air contaminant. Toxic air contaminant emissions at the facility would be dominated by diesel PM from off-road and on-road equipment. Therefore, fugitive dust emissions from material sorting and handling were evaluated as criteria pollutants and were not included in the health risk assessment. Metal TACs resulted from traveling of transfer equipment (loaders) were estimated using PM10- based emission factors from operations generating dust from green waste composting (SJVAPCD 2016a).

The estimated compost throughput is 210,000 tons for full operation. The emission factors were calculated on a per wet ton basis of organic material, and to ensure conservatism, the analysis assumes that the compost feedstock was composed entirely of organic materials (i.e., green and food materials). To be conservative, the entire composting site was modeled as an area source for composting VOC emissions. TAC speciation refers to the breakdown of emissions into individual TAC compounds based on emission factors or profiles. The TAC speciation of VOC emissions from composting is determined using the Composting Green Waste VOC Calculator (SJVAPCD 2016b). Off-road equipment paths are not fixed and, thus, off-road equipment activities were assumed to be distributed over the site, and both DPM and metal TACs in fugitive dust were modeled as area sources in AERMOD.

Biomass Gasification Facility
The specific technology and capacity of the future potential biomass facility are unknown. However, based on the current understanding of the EU Facility design and anticipated capacity, it was determined that a 2.5 megawatt (MW) gasification (biomass to energy) facility would be a representative facility to model for the HRA. Applying a factor of 12,000 tons of biomass per MW, for a 2.5 MW facility, an annual throughout of biomass fuel of 30,000 tons was assumed in the modeling (City of Roseville 2024). Emissions factors for another similar biomass gasification were applied as a representative facility (Climate Registry Default Emissions Factors 2021; Mustafa et al. 2017; EPA 2017; Yu et al. 2020). Biomass gasification emissions were modeled as a point source in AERMOD.

Air Quality Ascent
City of Roseville

3.3-20 Roseville Environmental Utilities Operations Center Project Draft EIR Odors
Impacts related to odors were assessed qualitatively, based on proposed construction activities, equipment types and duration of use, overall construction schedule, operational activities, and distance to nearby sensitive receptors.

THRESHOLDS OF SIGNIFICANCE
Thresholds of significance are based on Appendix G of the State CEQA Guidelines and thresholds of significance adopted by PCAPCD. PCAPCD’s air quality thresholds of significance are tied to achieving or maintaining attainment designations with the NAAQS and CAAQS, which are scientifically substantiated, numerical concentrations of criteria air pollutants considered to be protective of human health. Implementation of the project would have a significant impact related to air quality such that human health would be adversely affected if it would:
 conflict with or obstruct implementation of an applicable air quality plan;  cause construction‐generated criteria air pollutant or precursor emissions to exceed the PCAPCD‐recommended thresholds of 82 pounds per day (lb/day) for ROG, 82 lb/day for NOX, or 82 lb/day PM10 (PCAPCD 2017: 21);  result in a net increase in long-term project level operational criteria air pollutant or precursor emissions that exceed the PCAPCD-recommended thresholds of 55 lb/day for ROG, 55 lb/day for NOx, and 82 lb/day for PM10 (PCAPCD 2017: 21);
 expose sensitive receptors to substantial concentrations of CO;  expose sensitive receptors to substantial incremental increase in TAC emissions that exceed 10 in 1 million for carcinogenic risk (i.e., the risk of contracting cancer) and/or a noncarcinogenic Hazard Index (HI) of 1.0 or greater; or  create objectionable odors affecting a substantial number of people.

ISSUES NOT DISCUSSED FURTHER
Localized emissions of mobile-source CO are not assessed further. The SVAB has been in attainment for CO since 1998, and as vehicle fleets in California continue to become cleaner, CO impacts are less of a concern. Hence, localized mobile-source CO emissions associated with the project are not anticipated to exceed PCAPCD thresholds and therefore are not discussed further in this analysis.

ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES
Impact 3.3-1: Conflict with or Obstruct Implementation of the Applicable Air Quality Plan Phase 1
The implementation of Phase 1 of the project would not conflict with the City of Roseville 2035 General Plan, which is developed to guide growth in a manner that minimizes air pollution and protect public health and is used as a basis for regional air quality planning. Therefore, Phase 1 of the project would not conflict with the objectives of the applicable air quality plan (i.e., Sacramento 2015 Regional 8-Hour Ozone Attainment and Reasonable Further Progress Plan) or with further progress towards achieving attainment. This impact would be less than significant.

In August 2025, EPA finalized their determination that the Sacramento Metro area attained the 2008 8-hour ozone NAAQ by its December 31, 2024, attainment date as well as a determination that the requirement for the State to have contingency measures for reasonable further progress and attainment for the 2008 ozone NAAQS no longer applies to this area (EPA 2025d). The SVAB is currently designated as nonattainment for the CAAQ PM10 standard and the NAAQ 2015 8-hour ozone standard, as discussed in Section 3.3.2, “Environmental Setting.” PCAPCD is part of SMAQMD AQAP, which presents comprehensive strategies to reduce volatile organic compounds, NOX and PM10 emissions from stationary or area, mobile, and indirect sources to achieve attainment status with respect to NAAQS

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-21 and CAAQs. As shown under Impact 3.3-2, construction and operational emissions of PM10 and ozone precursors (ROG and NOX) from Phase 1 of the project would not exceed the PCAPCD thresholds of significance. Phase 1 of the project would not exceed the applicable thresholds and thus would not conflict with or obstruct implementation of the Sacramento 2015 Regional 8-Hour Ozone Attainment and Reasonable Further Progress Plan to attain NAAQS and CAAQS in the SVAB.

The emission inventories used to develop applicable air quality plans are based primarily on projected population and employment growth for the SVAB. This growth is estimated for the region, based in part on the planned growth identified in regional and local land use plans (e.g., General Plan, regional transportation plan). Therefore, projects that result in increases in employment growth beyond that projected in regional or local plans could result in emissions beyond those forecasted in the applicable plans. The General Plan land uses and associated growth projections are used to inform regional transportation planning (i.e., SACOG MTP/SCS), in which the air quality planning emissions forecasts and reduction are based, As discussed above in Section 3.3.1, “Regulatory Setting,” the SACOG MTP/SCS establishes a long-range development pattern that identifies the general location of different types of land uses, residential densities, and employment densities. The MTP/SCS addresses air quality by aligning transportation and land use planning with regional and State air quality goals. The SACOG 2025 MTP/SCS forecasts residential and employment growth throughout the City of Roseville and specifically identifies the area in which the project site is located as an established community projected for employment growth (SACOG 2026). Therefore, land use and growth consistency with the General Plan and the MTP/SCS would inherently demonstrate consistency with regional air quality planning. The existing General Plan land use designation for the project site is Public/Quasi-Public (P/QP) which establishes areas for municipal, governmental, or public facilities. The zoning for the project site is Planned Development (PD). A Planned Development district is a special purpose district that is intended to be applied in circumstances where the desired mix of uses cannot be achieved with a residential, commercial, or industrial mixed-use district when combined with a special area overlay. Because Phase 1 includes the development of government offices and municipal corporation yard facilities, the project would be consistent with the land use designations and zoning established by the City of Roseville. Therefore, Phase 1 of the project would not conflict with the City General Plan or the emissions forecasts contained within the AQAP, and the project would not conflict with long-term regional air quality planning efforts. This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Phase 2
PCAPCD and other air districts within the SVAB develop air quality plans to enable the region to achieve compliance with the 8-hour ozone attainment standards. These air quality plans are based on an inventory of existing emission sources and projections under future land use development. Further, relating to stationary emissions sources specifically, the plan identifies that through air district permit compliance, stationary sources emissions would be limited and controlled appropriately. Because the project would not result in increases in population or employment growth beyond that projected in the regional MTP/SCS, and would not conflict with the City General Plan, the project would not conflict with the objective of the applicable air quality plan (i.e., Sacramento 2015 Regional 8-Hour Ozone Attainment and Reasonable Further Progress Plan). For these reasons, this impact would be less than significant.

PCAPCD and other air districts within the SVAB developed the Sacramento 2015 Regional 8-Hour Ozone Attainment and Reasonable Further Progress Plan to address 8-hour ozone attainment. The emission inventories used to develop applicable air quality plans are based primarily on projected population and employment growth for the SVAB. This growth is estimated for the region, based in part on the planned growth identified in regional and local land use plans (e.g., General Plan, regional transportation plan). Therefore, projects that result in increases in employment growth beyond that projected in regional or local plans could result in emissions beyond those forecasted in the applicable plans. Phase 2 of the project would be operational by 2040 and would include an additional 122,000 square feet of building area for the RRTO Facility and the construction of 37,000 square feet of building area for the potential Future Organics Processing Facility. As shown in Table 3.3-5, operational emissions associated with Phase 2

Air Quality Ascent
City of Roseville

3.3-22 Roseville Environmental Utilities Operations Center Project Draft EIR would exceed the PCAPCD thresholds of significance. In addition, as specified under Impact 3.3-3, daily operational emissions associated with full operation (2058) would exceed PCAPCD thresholds. However, the AQAP identifies that for stationary emission sources, compliance with air district permitting and associated emissions limits is the primary action needed for the region to continue further progress towards attainment (see additional discussion below in Impact 3.3-2 regarding permitting).

As discussed above in Section 3.3.1, “Regulatory Setting,” the SACOG MTP/SCS establishes a long-range development pattern that identifies the general location of different types of land uses, residential densities, and employment densities. The MTP/SCS addresses air quality by aligning transportation and land use planning with regional and State air quality goals. The SACOG 2025 MTP/SCS forecasts residential and employment growth throughout the City of Roseville and specifically identifies the area in which the project site is located as an established community projected for employment growth (SACOG 2026). The project does not include land use development that would result in population growth beyond what has already been anticipated and planned for, and, therefore, would not generate long-term emissions that would conflict with the applicable AQAP. Rather, the project would continue to serve the City’s existing population and waste generation (Phase 1) and would be designed to accommodate increased growth anticipated in the City of Roseville, which is planned for in the 2035 Roseville General Plan. Because the project would not result in employment growth beyond that projected in the regional plan, the project would not conflict with or obstruct the implementation of the air quality plan. In addition, as discussed above for Phase 1, the existing land use designation for the project site is P/AQP and the zoning is PD. Phase 2 and full operation (2058) of the project would be consistent with the land use designations and zoning established in the City General Plan. Because the City General Plan was developed to guide growth in a manner that minimizes air pollution and protects public health and is the basis for the regional emissions forecasts and reduction targets in the AQAP, consistency with land uses and growth in the General Plan would also be consistency with the AQAP; thus, a project that is consistent with the General Plan would not impede attainment of air quality standards.

For these reasons, implementation of the project would not conflict with the goals of the Sacramento 2015 Regional 8-Hour Ozone Attainment and Reasonable Further Progress Plan to attain NAAQS and CAAQS in the SVAB.

This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Impact 3.3-2: Construction Emissions of Criteria Air Pollutants and Ozone Precursors Phase 1
The construction activities associated with Phase 1 would involve mass grading and facility construction, which would result in emissions of ROG, NOX, and particulate matter from the use of heavy-duty construction equipment, travel on unpaved surfaces, and earth movement for site preparation and grading activities. Construction activities would not exceed the applicable PCAPCD daily threshold of 82 lb/day for ROG, NOX, or PM10. Therefore, this impact would be less than significant.

Construction of Phase 1 would involve approximately 116 acres of ground disturbance including vegetation removal and grading. Typical construction activities associated with Phase 1 would require earthmoving equipment (e.g., graders, compactors, loaders, dozers, and excavators), concrete mix trucks and concrete pumps, cranes, welders, pavers, rollers, trucks, and personal autos as necessary. Pile driving and blasting are not anticipated. Excavation would be required for the installation of drains, utilities, and foundations. Emissions of NOX would be primarily associated with off-road (e.g., gas and diesel) construction equipment exhaust. On-road trucks for the import and export of materials and worker commuting would be secondary sources. Worker commute trips in gasoline-fueled vehicles and application of architectural coatings would be the primary sources of ROG, with additional ROG coming from off- and on-road construction equipment.

Fugitive dust emissions of PM10, and PM2.5 are associated primarily with site preparation and grading and vary as a function of soil silt content, soil moisture, wind speed, acreage of disturbance, and VMT on and off the site.

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-23 Construction mass emissions were modeled based on anticipated construction activities (e.g., earth work, building construction, equipment installation, paving) that would be required for each phase of the project. During Phase 1, initial earth work and construction of associated components is anticipated to take up to 18 months, with construction beginning as early as 2027. For construction activities associated with Phase 2, construction would involve expansion of the RRTO Facility and construction of the Potential Future Organics Processing Facility and generally is anticipated to occur on an as-needed basis as the facility’s capacity increases through Phase 2. Overall, the totality of construction activities would occur over a 14-year period (2027 through 2040) with an anticipated gap of approximately seven years prior to Phase 2 development. To determine maximum daily emissions, initial earthwork was overlapped with subsequent activities (Phase 1) and the most intensive construction activities associated with Phase 2 were used. Refer to Appendix B for specific equipment hours and construction activity associated with each component of the project.

Table 3.3-4 summarizes the modeled construction-related emissions of criteria air pollutants and ozone precursors for the project. The significance of construction-related air quality impacts was determined by comparing these modeling results with the applicable PCAPCD significance thresholds.

Table 3.3-4 Unmitigated Maximum Daily Emissions of Criteria Air Pollutants and Precursors Emissions Associated with Project Construction (lb/day)1
Construction Component ROG (lb/day) NOX (lb/day) PM10 (lb/day) Phase 1 (2027-2038)
Project Earthwork 5 31 31
RRTO Facility (Phase 1) 3 17 8
EU Services Facility 4 19 10
Equipment Maintenance Facility 4 24 11
Vendor Lease Area 3 14 8
Phillips Rd and Force Main Improvements 5 27 26
Electrical Substation 3 13 3
Overlap Project Earthwork and Vendor Lease Area 8 45 39 Overlap Project Earthwork, Philip Road and Force Main Improvements, and Electrical Substation 13 71 60 Overlap EU Services Facility and Equipment Maintenance Facility 8 43 22 Phase 1 Max Daily 13 71 60
PCAPCD Thresholds of Significance 82 82 82
Exceed Threshold? No No No
Phase 2 (2035-2040)
RRTO Facility (Phase 2) 3 12 8
Potential Future Organics Processing Facility 3 17 8
Overlap RRTO Facility (Phase 2) and Potential Future Organics Processing Facility 6 30 16 Phase 2 Max Daily 6 30 16
PCAPCD Thresholds of Significance 82 82 82
Exceed Threshold? No No No
Notes: ROG = reactive organic gas; NOX = oxides of nitrogen; PM10 = respirable particulate matter; lb/day = pounds per day; PCAPCD = Placer County Air Pollution Control District. Daily emissions for overlapping components are calculated by summing the daily emissions of each individual component. 1 The emissions for Phase 1 and Phase 2 are not additive as components associated with each project phase were modeled separately, based on the anticipated phasing of development.
2 Fugitive dust controls incorporated into the emissions modeling, in accordance with commitments in Chapter 2, “Project Description.” Source: Modeling conducted by Ascent in 2025.

Air Quality Ascent
City of Roseville

3.3-24 Roseville Environmental Utilities Operations Center Project Draft EIR According to the PCAPCD guidance, projects with daily emissions exceeding the thresholds of 82 lb/day for ROG, NOx, or PM10 would have a significant impact on air quality. As shown in Table 3.3-4, Phase 1 project construction is anticipated to generate emissions that would not exceed the established maximum daily for ROG, NOx, or PM10 daily thresholds. Further, all construction activities would be required to comply with PCAPCD rules and regulations designed to reduce particulate matter emissions. Specifically, these include Rule 401.1 through 401.9 and would require active watering/stabilizing of exposed dirt, reduced speeds for trucks, and covering active piles. Complete details are described above in Section 3.3.1, “Regulatory Setting.” Incorporation of these measures would further reduce dust emissions. Because PCAPCD thresholds of significance are directly tied to attaining the NAAQs, projects that do not exceed these thresholds would be considered not to contribute to adverse health effects. For these reasons, construction emissions associated with Phase 1 of the project would be less than significant.

Mitigation Measures
No mitigation is required.

Phase 2
Phase 2 of the project would involve the construction of additional square footage at the RRTO Facility and the construction of a Potential Future Organics Processing Facility, which could include a future composting and/or biomass facility. Construction of Phase 2 of the project would include the use of off-road equipment, material delivery, worker commute trips, and building construction. Because Phase 2 construction activities would not exceed the PCAPCD-recommended thresholds of 82 lb/day for ROG, NOX, or PM10, this impact would be less than significant.

Phase 2 of the project would include expansion of the RRTO Facility and construction of the Potential Future Organics Processing Facility, all of which would be located within the boundaries of the project site and would not include improvements to Phillip Road (which would be constructed as part of Phase 1). For modeling purposes, Phase 2 construction is estimated to take place between 2035 and 2040 (see Table 3.3-4). Similar to Phase 1, Phase 2 construction activities (e.g., hauling and operation of off-road equipment, material delivery, worker commute trips, building construction, paving, and architectural coating) would result in emissions of ROG, NOX, and particulate matter (e.g., PM2.5 and PM10). The maximum daily emissions for Phase 2 project construction are presented in Table

3.3-4 and model inputs and outputs are available in Appendix C.

According to PCAPCD guidance, projects with daily emissions exceeding the thresholds of 82 lb/day for ROG, NOX, or PM10 would have a significant impact on air quality. As shown in Table 3.3-4, construction of Phase 2 is not anticipated to generate emissions that would exceed the established daily maximum for ROG, NOX, or PM10. Because PCAPCD thresholds of significance are directly tied to attaining the NAAQS, projects that exceed thresholds would be considered to contribute to adverse health effects. For these reasons, construction emissions from Phase 2 of the project would not result in negative health outcomes. This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Impact 3.3-3: Long-term Operational Emissions of Criteria Air Pollutants and Ozone Precursors Phase 1
Implementation of Phase 1 of the project would result in operational emissions from the use of on-site equipment and waste acceptance activities, building-related energy, and area-wide sources (e.g., landscaping equipment) as well as from mobile sources associated with employee commute and truck travel. Based on the modeling conducted, operational emissions would not exceed the PCAPCD thresholds of significance or substantially contribute to concentrations that exceed NAAQS or CAAQS. Impacts related to these long-term operational (regional) emissions would be less than significant.

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-25 Phase 1 of the project would involve the operation of the RRTO Facility that would provide an on-site materials recovery facility to segregate recyclable material; an area for receiving and transferring municipal solid waste; and an area for receiving, processing, and transferring organic waste; the Vendor Lease Area for prospective vendors to commit materials to the RRTO Facility; and the Corporation Yard. Emissions associated with operation of Phase 1 include emissions from mobile sources, including trucks used to transport municipal solid waste (MSW) and organic wastes and vehicles used by employees to travel to and from the facility. Table 3.3-5 summarizes the modeled operational emissions of criteria air pollutants and ozone precursors for the project.

Table 3.3-5 Unmitigated Criteria Air Pollutant and Precursor Emissions Associated with Project Operation Operation Component ROG (lb/day) NOX (lb/day) PM10 (lb/day) Phase 1 (2028)
Area Sources 6 <1 <1
Building Energy1 0 0 0
Mobile - Trucks 1 16 2
Mobile - Worker Commute 16 8 1
MRF Material Sorting/Handling 0 0 1
MRF Material Transfer Off-road <1 2 <1
Total Daily Operational Emissions 23 26 4
Significance Threshold 55 55 82
Exceed Threshold? No No No
Phase 2 (2040)
Area Sources 16 <1 <1
Building Energy1 0 0 0
Onsite Fueling Station 1 0 0
Equipment Maintenance 1 0 0
Mobile - Trucks 1 9 4
Mobile - Worker Commute 14 3 1
MRF Material Sorting/Handling 0 0 2
MRF Material Transfer Off-road 1 3 <1
Organic Material Transfer Off-road 1 3 <1
Organics Compost 218 0 22
Biomass Gasification 5 320 254
Total Daily Operational Emissions 256 339 283
Significance Threshold 55 55 82
Exceed Threshold? Yes Yes Yes
Full Operation (2058)
Area Sources 16 <1 <1
Building Energy1 0 0 0
Onsite Fueling Station 1 0 0
Equipment Maintenance 1 0 0
Mobile - Trucks 1 14 7

Air Quality Ascent
City of Roseville

3.3-26 Roseville Environmental Utilities Operations Center Project Draft EIR Operation Component ROG (lb/day) NOX (lb/day) PM10 (lb/day) Mobile - Worker Commute 8 1 1
MRF Material Sorting/Handling 0 0 2
MRF Material Transfer Offroad Emission 1 4 <1
Organic Material Transfer Offroad Emission 1 6 <1
Organics Compost 412 0 42
Biomass Gasification 5 320 254
Total Daily Operational Emissions 446 345 306
Significance Threshold 55 55 82
Exceed Threshold? Yes Yes Yes
Notes: ROG = reactive organic gas; NOx = oxides of nitrogen; PM = particulate matter; lb/day = pounds per day; PCAPCD = Placer County Air Pollution Control District. Area source refers to the reapplication of architectural coating every 10 years. These unmitigated emissions include the project-specific VMT provided by Kittelson & Associates (2025). For Phase 2, the projected biomass feedstock quantities for the composting and gasification facilities at full operation (2058) were used, providing a conservative estimate of criteria air pollutant emissions. Note that the emissions for Phase 1 and Phase 2 are not additive as components associated with each project phase were modeled separately, based on the anticipated phasing of development. 1 Consistent with CalEEMod, “building energy” refers to energy use associated with building operations such as space heating, water heating.

Because buildings would be all electric (no natural gas boiler, furnaces or engines), there would be no onsite (direct) emissions of air pollutants.

Indirect emissions of air pollutants from power plants are generally associated with the permitted stationary source (the power plant itself), not the individual buildings.

Source: Modeled by Ascent in 2025.

As shown in Table 3.3-5, implementation of Phase 1 would generate emissions of criteria air pollutants currently under nonattainment status (i.e., ROG, NOX, and PM10). Based on the characteristics of Phase 1, operational maximum daily emissions would not exceed the PCAPCD significance thresholds (i.e., 55 lb/day for ROG and NOX or the threshold of 82 lb/per day for PM10. As detailed under Section 3.3.3, “Thresholds of Significance,” PCAPCD mass emissions thresholds have been developed in consideration of long-term air quality planning to attain the NAAQS and CAAQS. Because the PCAPCD thresholds of significance are directly tied to attaining NAAQS and CAAQS, projects that do not exceed these thresholds would not contribute to adverse health effects. For these reasons, operational emissions from Phase 1 would not result in negative health outcomes. This impact would be less than significant.

Mitigation Measures
No mitigation is required.

Phase 2
Phase 2 would involve the operation of additional square footage at the RRTO Facility and the operation of a Potential Future Organics Processing Facility, which could include a future composting and/or biomass facility. Similar to Phase 1, Phase 2 of the project would result in operational emissions from the use of on-site equipment and building-related energy as well as from mobile sources associated with employee commutes and operational truck travel. Based on the modeling conducted, operational emissions from Phase 2 and full operations would exceed PCAPCD thresholds of 55 lb/day for ROG and NOx, and the threshold of 82 lb/day for PM10 (Table 3.3-5). This impact would be significant.

Phase 2 of the project would be operational by 2040 and would include an additional 122,000 square feet of building area for the RRTO Facility and the construction of 37,000 square feet of building area for the Potential Future Organics Processing Facility (including the development of 34 acres of land). Similar to Phase 1, emissions associated with operation of Phase 2 would include emissions from mobile sources, including trucks used to transport MSW and organic wastes and vehicles used by employees to travel to and from the facility. Table 3.3-5 summarizes the modeled operation-related emissions of criteria air pollutants and ozone precursors under buildout conditions in 2040 after Phase 1 and Phase 2 have been completed. In addition, a full operations (2058) scenario was modeled to capture

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-27 additional anticipated waste throughput associated with long-term demand (i.e., 660,000 tons per year), including additional onsite equipment use and facility staff, to handle increased activities. As shown in Table 3.3-5, based on the characteristics of Phase 2, operational maximum daily emissions would exceed the PCAPCD thresholds of 55 lb/day for ROG and NOX and the threshold of 82 lb/per day for PM10, which could result in adverse health effects. The Potential Future Organics Processing Facility, which could include a future composting and/or biomass gasification facility, would generate the majority of operational emissions. Operation of the composting facility would result in an exceedance of ROG emissions during Phase 2, and operation of the biomass gasification facility would generate exceedances of NOx and PM₁₀ emissions. Expansion of the RRTO Facility alone would not result in an exceedance of the ROG, NOx, or PM10 thresholds. Nevertheless, because emissions associated with the RRTO Facility and Potential Future Organics Processing Facility would exceed the applicable thresholds, this impact would be significant.

Mitigation Measures
Mitigation Measure 3.3-3a: Reduce Fugitive Dust From Composting The following mitigation measure would be required if the City constructs and operates the composting component of the Potential Future Organics Processing Facility. To minimize fugitive PM₁₀ emissions from composting operations, including the use of an Aerated Static Pile (ASP) or a Covered Aerated Static Pile (CASP) system, the City shall implement the following dust control measures during all compost feedstock handling, pile building, screening, and on-site material movement activities:
 Moisture Control: Maintain compost feedstocks and active piles at optimal moisture levels to reduce dust generation during pile construction, loading, and unloading.  Water or Suppressants: Apply water or environmentally safe dust suppressants to stockpiles and material handling areas as needed to minimize visible dust emissions.  Wind Barriers or Vegetative Buffers: Install fencing, berms, or vegetative windbreaks around the perimeter of the composting and feedstock handling areas to reduce windblown dust generation.  Enclosed or Covered Operations: Where feasible, enclose or provide wind-sheltered structures for high-dustgenerating activities such as grinding or screening.  Monitoring and Response: Implement a visible dust observation program during active operations. If visible dust is observed beyond the property line, operations contributing to dust shall be temporarily suspended until effective dust control measures are applied.

Mitigation Measure 3.3-3b: Permitting-Level Ambient Air Quality Evaluation for Composting and/or Stationary Biomass Facility
The following mitigation measure would be required if the City constructs and operates the Potential Future Organics Processing Facility, which could include a future composting and/or biomass facility. Prior to issuance of a building permit or air quality permit for the installation or operation of the composting and/or any stationary biomass energy generation system, the City of Roseville shall prepare a permitting-level emissions evaluation, in coordination with PCAPCD. The evaluation shall:
 Estimate all criteria air pollutant emissions based on the proposed technology type, combustion or conversion process, equipment specifications, fuel throughput, stack parameters, and emission factors;  Quantitatively estimate daily and annual emissions in accordance with PCAPCD Rule 502 New Source Review; and  Identify and evaluate Best Available Control Technology (BACT) and other emission control measures or procure emissions offsets to reduce emissions, in accordance with PCAPCD emissions limits contained in Rule 502.

The ambient air quality evaluation shall be submitted to PCAPCD for review and the City shall incorporate identified BACT controls and/or emissions offsets, if necessary, to ensure that emissions achieve all emissions limits contained in PCAPCD’s Rule 502. Implementation of control technology and final site design shall be demonstrated prior to issuance of building permits.

Air Quality Ascent
City of Roseville

3.3-28 Roseville Environmental Utilities Operations Center Project Draft EIR Significance after Mitigation
Implementation of the identified dust control measures in Mitigation Measure 3.3-3a would substantially reduce fugitive PM₁₀ emissions from potential future composting operations by requiring site-specific best practices such as moisture control, traffic management, and suppression of dust-generating activities. Onsite dust suppression can generally achieve up to 75 percent reduction from onsite moving equipment, resulting in 6 lbs/day (Phase 2) and 11 lbs/day (Full Operation) associated with onsite equipment movement/material loading and unloading during composting, reported in Table 3.3-5 under the Biomass Composting category (SMAQMD 2020). However, considering the PM emissions are dominated by the gasification process and those alone exceed the thresholds, a 75 percent reduction in onsite PM emissions from material transfer would not bring total emissions down to below the thresholds. Implementation of Mitigation Measure 3.3-3b would require a permitting-level specific evaluation of the anticipated daily and annual emissions associated with the potential future on-site composting and/or biomass facility. Understanding that technology advances over time, the specific technology and associated emissions with the potential future composting and/or biomass facility is likely to be different than what was evaluated in this EIR; thus, Mitigation Measure 3.3-3b requires that based on the specific technology chosen in the future, including potential cogeneration features and emissions controls, that the facility meet all PCAPCD permitting requirements including emissions limits/offsets established by PCAPCD’s permitting process. Nonetheless, because ROG, NOx, and PM emissions may continue to exceed thresholds, this impact would remain significant and unavoidable.

Impact 3.3-4: Expose Sensitive Receptors to Substantial Pollutant Concentrations Phase 1 and Phase 2 (Construction)
An HRA was conducted to assess potential health risk exposure from construction and operation of the project. The HRA analyzed short-term diesel PM emissions during construction activities and long-term on- and off-site emissions sources (e.g., on-site: equipment use, fuel dispensing, vehicle maintenance, composting, biomass gasification; off-site:
diesel PM from waste delivery trucks). Based on the modeling conducted for the project-specific HRA, construction emissions would result in exceedances of PCAPCD’s risk threshold of 10 per million at nearby receptors. Non-cancer risk thresholds of Health Index 1 would not be exceeded. Because construction emissions would exceed PCAPCD’s risk threshold, this impact would be significant.

To fully evaluate the impacts of the project, a construction and operational HRA was conducted in accordance with PCAPCD guidance and CARB recommendations. Because the project would be built out in distinct phases over time, construction and operational emissions sources were modeled separately using different source parameters appropriate for each phase. This analysis considers all construction associated with Phase 1 and Phase 2 of the project. The operational phase of the project is discussed below under Phase 2, which assumed full operation in 2040.

Further, risk calculations also considered the extended duration of exposure that could occur as one portion of the project is built out and begins to operate while another portion begins to be constructed. The localized levels of TAC emissions from the proposed project were evaluated against existing health-based standards and CEQA guidelines.

Construction
Construction-related activities would result in temporary, intermittent emissions of diesel PM from the exhaust of offroad, heavy-duty diesel equipment used for site preparation, grading, trenching, building construction, paving and architectural coating, and other miscellaneous activities. On-road diesel-powered haul trucks traveling to and from the construction areas to deliver materials and equipment would also contribute to diesel PM and would affect the receptors around haul routes.

The nearest sensitive receptors that could be adversely affected by construction are existing residences including a residence along Phillip Road, approximately 235 feet south of the project site and residences along South Brewer Road, approximately 0.25 mile southwest of the project site. In addition, there is an existing, unoccupied residential structure within the Vendor Lease Area that may be demolished or repurposed for use by prospective vendors. The project site is also located within a 2-mile radius of several planned developments/communities (e.g., Creekview Specific Plan, West Roseville Specific Plan areas). The Phillip Road Site Project, a proposed mixed-use development in the City, is located approximately two miles east of the project site.

Ascent Air Quality
City of Roseville
Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-29 To estimate diesel PM emissions, the same modeling output that was described above for Impact 3.3-2 was used, and PM10 exhaust emissions were considered to be a surrogate for diesel PM. Average construction fleet vehicle emissions rates were applied. Diesel PM emissions from construction emissions modeling were applied to the air dispersion modeling outputs to obtain emissions concentrations, which were used to estimate health risks, using HARP 2. For more detailed information regarding the HRA methodology, inputs and outputs, refer to Appendix B.

Based on the emissions modeling conducted for construction activities alone, the maximally exposed individual receptor (MEIR) (i.e., home located approximately 235 feet south of the project site) would be exposed to an incremental increase in cancer risk of 12.5 per million, which would exceed PCAPCD’s health risk threshold for cancer risk of 10 per million. Noncancer health risk would not exceed PCAPCD’s health risk threshold of 1 on the HI. See Table 3.3-6 and Figure 3.3-1.

Because construction emissions would exceed PCAPCD’s risk threshold, this impact would be significant.

Table 3.3-6 Cancer and Non-Cancer Risks due to Construction Emissions Phase MEIR Cancer Risk (Per Million) MEIR Chronic Hazard Index Construction, Unmitigated 12.5 <0.1
Threshold 10 1
Threshold Exceeded? Yes No
Notes: MEIR = maximally exposed individual receptor; Hazard Index = non-cancer health risk.

Source: Modeled by Ascent in 2025.

Mitigation Measures
Mitigation Measure 3.3-4: Implement Clean Construction Fleet During all phases of project construction, all off-road diesel-powered construction equipment greater than 25 horsepower shall meet EPA’s Tier 4 emission standards, as defined in 40 CFR 1039, and comply with the appropriate test procedures and provisions contained in 40 CFR Parts 1065 and 1068. This measure can also be achieved by using battery-electric off-road equipment as it becomes available. The City shall require the primary construction contractor(s) and its subcontractor(s) to submit copies of the valid Certificate of Reported Compliance for their fleets prior to awarding a contract. In addition, all construction equipment shall be subject to inspection for regulatory compliance.

Implementation of this measure shall be required in the contract the City establishes with its construction contractors.

Significance after Mitigation
Applying Mitigation Measure 3.3-4 would substantially reduce diesel PM and NOx emissions associated with construction activities. Using the modeling conducted for the project, which applied statewide construction fleet emissions factors, and applying Tier 4 emissions rates to all equipment larger than 25 horsepower, cancer risk at the MEIR would be reduced from 12.5 per million to 2.0 per million for contracting cancer over a 70-year lifetime, which is below the PCAPCD thresholds of 10 per million. Figure 3.3-2 shows the cancer risk results from project construction after mitigation is applied. See Appendix B for further details. With incorporation of Mitigation Measure 3.3-4, this impact would be reduced to a less-than-significant level.

Phase 1 and Phase 2 (Operation)
The HRA for combined Phase 1 and Phase 2 of the project evaluated all on-site activities as well as the operation of a potential future compost facility and a 2.5 MW potential future biomass gasification facility, which could be developed at full operation (2058) of the project. Based on the modeling conducted for the project-specific HRA, Phase 2 of the project (operations alone) would not result in the exposure of sensitive receptors to TAC emissions in excess of 10 in 1 million cancer risk or a non-carcinogenic health risk greater than 1.0 on the Hazard Index. When considering the combined effect of project construction with full operation, the project would result in a combined excess cancer risk of 18.5 per million, exceeding PCAPCD’s 10 per million threshold. The Hazard Index threshold would not be exceeded. Because the combined effect of project construction with full operation would exceed PCAPCD’s risk threshold, this impact would be significant.

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3.3-30 Roseville Environmental Utilities Operations Center Project Draft EIR Source: Adapted by Ascent in 2025.

Figure 3.3-1 Cancer Risk Map (Project Construction, Unmitigated)

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-31 Source: Adapted by Ascent in 2025.

Figure 3.3-2 Cancer Risk Map (Project Construction, Mitigated)

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3.3-32 Roseville Environmental Utilities Operations Center Project Draft EIR As detailed above, to fully evaluate the impacts of the project, a construction and operational HRA was conducted in accordance with PCAPCD guidance and CARB recommendations. The HRA for combined Phase 1 and Phase 2 of the project evaluated all on-site activities as well as the operation of a potential future compost facility and a 2.5 MW potential future gasification biomass facility.

Operations
Operational activity was modeled in the HRA to determine the maximum future risk exposure associated with full operation of the project. Full operation would include the maximum anticipated waste throughput of 660,00 tpy of waste, including 210,000 tpy of organics. Based on the anticipated 2.5 MW potential future biomass facility and estimated capacity of 12,000 tons of biomass per 1 MW, 30,000 tpy of organic waste was assumed to be processed through the potential future biomass facility. In addition, to handle the waste, on-site diesel equipment would be required at the potential future composting site, on-site diesel material trucks would be used to deliver and transfer material, gasoline and diesel dispensing would occur at the on-site fueling station, maintenance of equipment could result in VOC off-gassing emissions, and various TAC emissions would be associated with the potential future composting and biomass gasification facility.

For the purposes of the HRA, operational-related emissions of diesel PM were estimated using CalEEMod emission factors, as described above in Impact 3.3-2 and under the “Methodology” subheading. Emissions from other sources (e.g., biomass gasification, composting, on-site fuel dispensing) were modeled using appropriate emissions factors and anticipated operational activity schedules. Similar to methods described above, air dispersion modeling was conducted in AERMOD for full operation and ground-level concentrations were obtained at nearby receptors. Full details of emissions factors and operational activity rates are contained in Appendix B.

Based on the emissions modeling conducted for operational activities alone, the MEIR (i.e., home located approximately 225 feet south of the project site) would be exposed to an incremental increase in cancer risk of 6.0 per million, which would not exceed PCAPCD’s health risk threshold for cancer risk of 10 per million. In addition, noncancer health risk would not exceed PCAPCD’s health risk threshold of 1 on the Hazard Index. See Table 3.3-7 and Figure 3.3-3.

Table 3.3-7 Cancer and Non-Cancer Risks due to Operational Emissions Phase MEIR Cancer Risk (Per Million) MEIR Chronic Hazard Index MEIR Acute Hazard Index Full Operation (2058) 6.0 <0.1 0.3
Threshold 10 1 1
Threshold Exceeded? No No No
Notes: MEIR = maximally exposed individual receptor; Hazard Index = non-cancer health risk.

Source: Modeled by Ascent in 2025.

Combined Construction and Operations
As described above, health risk was assessed for the construction and operations phases of the project, separately. In addition, to provide an absolute worst-case scenario, where the same receptors could potentially be exposed to TACs from both construction and operational activities, a combined construction and operational scenario was modeled.

This scenario may not occur, if for example, residents living in one home now move out within the next 30 years of project buildout and, therefore, are not actually exposed to both construction and operational emissions.

Nonetheless, this scenario assumes that any one receptor could potentially be exposed to diesel PM exhaust during all phases of construction and all on- and off-site emissions sources during full operations.

As shown in Figure 3.3-3, cancer risk results are concentrated closer to the onsite equipment (orange and yellow contours) with some cancer risk estimates also associated with primary access roads (dark green). The modeling assumes that 90 percent of traffic would move west from the site, while 10 percent heads east. Refer to Appendix B for more details regarding modeling inputs.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-33 Source: Adapted by Ascent in 2025.

Figure 3.3-3 Cancer Risk Map (Project Operations, Unmitigated)

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3.3-34 Roseville Environmental Utilities Operations Center Project Draft EIR Understanding that construction risk alone at the MEIR (i.e., cancer risk of 12.5 per million) would exceed the 10 per million cancer-risk threshold, when combined with operations (i.e., 6.0 per million at the MEIR), the maximum cancer risk level at the MEIR would be 18.5 per million of excess cancer risk, exceeding the 10 per million threshold. Noncancer risk would not exceed PCPACD’s thresholds. See Table 3.3-8 and Figure 3.3-4 for cancer risk results from this combined scenario.

Table 3.3-8 Cancer and Non-Cancer Risks due to Construction and Operational Emissions Phase MEIR Cancer Risk
(Per Million) MEIR Chronic Hazard Index MEIR Acute Hazard Index MEIR Location (X, Y) Combined Construction and Operation
(Full Operation)

18.5 <0.1 0.3 635808.26,
4295924.81
Threshold 10 1 1 -
Threshold Exceeded? Yes No No -
Notes: MEIR = maximally exposed individual receptor; Hazard Index = non-cancer health risk.

Source: Modeled by Ascent in 2025.

Because the combined effect of project construction with full operation (2058) would exceed PCAPCD’s risk threshold, this impact would be significant.

Mitigation Measures
Implement Mitigation Measure 3.3-4, described above.

Significance after Mitigation
Applying Mitigation Measure 3.3-4 would substantially reduce diesel PM and NOx emissions associated with construction activities. As described above, implementation of this measure would reduce construction-related cancer risk exposure to 2 per million. Combining this with operational risk alone (i.e., 6.0 per million) would result in a combined maximum cancer risk of 8.0 per million, which would be below PCAPCD’s 10 per million threshold. Figure

3.3-5 shows the cancer risk results from project operation after mitigation is applied. Figure 3.3-6 shows the cancer risk results from project construction and operation combined after mitigation is applied. Refer to Appendix B for mitigated scenario modeling. With incorporation of Mitigation Measure 3.3-4, this impact would be reduced to a less-than-significant level.

Impact 3.3-5: Create Objectionable Odors Affecting a Substantial Number of People Phase 1
Phase 1 of the project would introduce new odor sources into the area such as temporary diesel exhaust emissions from construction equipment and the movement of trucks during construction. However, these odor sources would be temporary, intermittent, and dissipate rapidly from the source. Operational activities would include truck idling and municipal solid waste (MSW) and organic waste delivery and transfer. Implementation of applicable best management practices (BMPs) would minimize odors and the project would be subject to PCAPCD Rule 205, which prohibits the discharge of air contaminants or other materials that would cause detriment, nuisance, or annoyance.

However, because existing sensitive uses are located within PCAPCD-screening distances and planned future growth in Roseville could occur prior to operations of Phase 1, resulting in new sensitive uses within the 2-mile buffer, the potential for the project to cause objectionable odors remains. Thus, this impact would be potentially significant.

Construction
The predominant source of power for construction equipment is diesel engines. Exhaust odors from diesel engines, as well as emissions associated with paving and the application of architectural coatings may be considered offensive to some individuals. The generation of these odor emissions would vary greatly on a day-to-day basis depending on the type of construction activities.

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-35 Source: Adapted by Ascent in 2025.

Figure 3.3-4 Cancer Risk Map (Project Construction and Operation Combined, Unmitigated)

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3.3-36 Roseville Environmental Utilities Operations Center Project Draft EIR Source: Adapted by Ascent in 2025.

Figure 3.3-5 Cancer Risk Map (Project Operations, Mitigated)

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Roseville Environmental Utilities Operations Center Project Draft EIR 3.3-37 Source: Adapted by Ascent in 2025.

Figure 3.3-6 Cancer Risk Map (Project Construction and Operation Combined, Mitigated)

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3.3-38 Roseville Environmental Utilities Operations Center Project Draft EIR Application of architectural coatings would also be a source of offensive odors from volatile organic compounds.

However, because the application of architectural coatings would be required to comply with PCAPCD Rule 218 (Architectural Coatings) which requires volatile organic compound limits on coatings used, potential construction odors would be minimized. Minor odors from the use of heavy-duty diesel equipment would be intermittent and temporary and would dissipate rapidly from the source with an increase in distance. Existing off-site receptors include residences located approximately 235 feet south, 0.25 miles west, and 1.7 miles east of the project site. Given the temporary nature of construction activities and the distance of the sensitive receptors from the project site, project construction is not anticipated to result in a significant odor-related impact.

Operations
PCAPCD identifies land uses typically associated with potential odor impacts including wastewater treatment plants, sanitary landfills, composting/green waste facilities, recycling facilities, chemical manufacturing plants, painting/coating operations, agricultural operations, and slaughterhouse/food packaging plants (PCAPCD 2017: 63- 64). The project site is predominantly agricultural and currently used for farming; thus, some odors (e.g., operation of equipment with diesel exhaust) would be similar to existing operations. Operational odor sources associated with Phase 1 of the project would include diesel exhaust from idling trucks, MSW, and organic waste. Diesel-fueled trucks would be moving in and out of the facility and would not be idling for an extended period (i.e., no longer than five minutes). In addition, over time, the EU fleet would convert from an internal combustion engine fleet to a zero emission or reduced emission fleet, thus reducing the odors associated with truck deliveries and operation.

Odors associated with project operation (i.e., transfer station, green waste) are identified as major odor sources by PCAPCD (PCAPCD 2017: 63-64). These objectionable odors are generated from the municipal solid waste delivered and processed at the transfer station. Waste materials received at transfer stations also include organic residues such as food and yard waste that generate odors when they decompose. Odiferous volatile organic compounds can be generated when organic waste breaks down. These odors can range from sweet to pungent to rancid or musty with the intensity of the smell depending upon the material received, the speed with which they are processed, whether or not the wastes are processed indoors, and the distance from the source.

PCAPCD identifies the distance between odor source and receptors as one of the most important factors influencing odor impacts and recommends screening distances for a variety of odor-generating facilities (PCAPCD 2017: 64). The recommended screening distance for green waste and composting facilities is 2 miles. Although the project site is located within 2 miles of existing sensitive receptors, one of the project objectives is to limit odors associated with recycling by maintaining an appropriate distance from nearby residential and other sensitive uses. In accordance with this objective, the RRTO Facility would be strategically configured such that more industrial features (e.g., waste unloading and transfer) are located further from Phillip Road and from nearby sensitive uses. In addition, as discussed in Chapter 2, “Project Description,” the City is a member of the Western Placer Waste Management Authority (WPWMA) and would continue to send a portion of its waste to WPWMA through June 2043. WPWMA has developed a Site Wide Odor Plan (SWOP) that includes Best Management Practices (BMPs) utilized by WPWMA to mitigate the release of odors from WPWMA facilities, including material recovery facility and composting operations (WPWMA 2024: 3). The BMPs focus on timely and consistent processing of materials and regular facility maintenance to avoid the accumulation of potentially odiferous materials. The City would implement similar BMPs applicable to the RRTO Facility, many of which are required to comply with statewide regulations, such as processing waste materials within 48 hours of receipt of the material, regularly inspecting, and properly maintaining material stockpiles or alternative BMPs approved by the respective permitting authorities (WPWMA 2024: 16). Implementation of applicable BMPs would minimize odors associated with the RRTO Facility and other components of Phase 1 of the project.

In addition, emissions of odors would be subject to PCAPCD Rule 205, Nuisance, which prohibits the discharge of air contaminants or other materials that would cause detriment, nuisance, or annoyance to any considerable number of people. However, because existing sensitive uses are located within PCAPCD-screening distances and planned future growth in Roseville could occur prior to operations of Phase 1, resulting in new sensitive uses within the 2-mile buffer, the potential for the project to cause objectionable odors remains.