typically emitted in smaller quantities, but because they are potent GHGs, they are sometimes referred to as high global-warming-potential (GWP) gases.
• Chlorofluorocarbons (CFCs) are GHGs covered under the 1987 Montreal Protocol and used for refrigeration, air conditioning, packaging, insulation, solvents, or aerosol propellants. Since they are not destroyed in the lower atmosphere (troposphere, stratosphere), CFCs drift into the upper atmosphere where, given suitable conditions, they break down ozone. These gases are also ozonedepleting gases and are therefore being replaced by other compounds that are GHGs covered under the Kyoto Protocol.
• Perfluorocarbons (PFCs) are a group of human-made chemicals composed of carbon and fluorine only. These chemicals (predominantly perfluoromethane [CF4] and perfluoroethane [C2F6]) were introduced as alternatives, along with HFCs, to the ozone-depleting substances. In addition, PFCs are emitted as by-products of industrial processes and are used in manufacturing. PFCs do not harm the stratospheric ozone layer, but they have a high global warming potential. • Sulfur Hexafluoride (SF6) is a colorless gas soluble in alcohol and ether, slightly soluble in water.
SF6 is a strong GHG used primarily in electrical transmission and distribution systems as an insulator. • Hydrochlorofluorocarbons (HCFCs) contain hydrogen, fluorine, chlorine, and carbon atoms.
Although ozone-depleting substances, they are less potent at destroying stratospheric ozone than CFCs. They have been introduced as temporary replacements for CFCs and are also GHGs. • Hydrofluorocarbons (HFCs) contain only hydrogen, fluorine, and carbon atoms. They were introduced as alternatives to ozone-depleting substances to serve many industrial, commercial, and personal needs. HFCs are emitted as by-products of industrial processes and are also used in manufacturing. They do not significantly deplete the stratospheric ozone layer, but they are strong GHGs (IPCC 2001; USEPA 2022).
GHGs are dependent on the lifetime or persistence of the gas molecule in the atmosphere. Some GHGs have stronger greenhouse effects than others. These are referred to as high GWP gases. The GWP of GHG emissions are shown in Table 8, GHG Emissions and Their Relative Global Warming Potential Compared to CO2. The GWP is used to convert GHGs to CO2-equivalence (CO2e) to show the relative potential that different GHGs have to retain infrared radiation in the atmosphere and contribute to the greenhouse effect. For example, under IPCC’s Fourth Assessment Report (AR4) GWP values for CH4, a project that generates 10 MT of CH4 would be equivalent to 250 MT of CO2.12
Table 8 GHG Emissions and Their Relative Global Warming Potential Compared to CO2 GHGs
Second Assessment Report (SAR)
Global Warming
Potential Relative to CO2
1 Fourth Assessment Report (AR4)
Global Warming
Potential Relative to CO2
1 Fifth Assessment Report (AR5)
Global Warming
Potential Relative to CO2
1 12 The global warming potential of a GHG is dependent on the lifetime, or persistence, of the gas molecule in the atmosphere.
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Table 8 GHG Emissions and Their Relative Global Warming Potential Compared to CO2 GHGs
Second Assessment Report (SAR)
Global Warming
Potential Relative to CO2
1 Fourth Assessment Report (AR4)
Global Warming
Potential Relative to CO2
1 Fifth Assessment Report (AR5)
Global Warming
Potential Relative to CO2
1 Carbon Dioxide (CO2) 1 1 1
Methane2 (CH4) 21 25 28
Nitrous Oxide (N2O) 310 298 265
Source: IPCC 1995, 2007, 2013.
Notes: The IPCC published updated GWP values in its Fifth Assessment Report (AR5) that reflect new information on atmospheric lifetimes of GHGs and an improved calculation of the radiative forcing of CO2. However, GWP values identified in AR4 are used by South Coast AQMD to maintain consistency in statewide GHG emissions modeling. In addition, the 2017 Scoping Plan Update was based on the GWP values in AR4. 1 Based on 100-year time horizon of the GWP of the air pollutant compared to CO2. 2 The methane GWP includes direct effects and indirect effects due to the production of tropospheric ozone and stratospheric water vapor. The indirect effect due to the production of CO2 is not included.
GHG Regulatory Setting
REGULATION OF GHG EMISSIONS ON A NATIONAL LEVEL
The US Environmental Protection Agency (EPA) announced on December 7, 2009, that GHG emissions threaten the public health and welfare of the American people and that GHG emissions from on-road vehicles contribute to that threat. The EPA’s final findings respond to the 2007 U.S. Supreme Court decision that GHG emissions fit within the Clean Air Act definition of air pollutants. The findings do not in and of themselves impose any emission reduction requirements but allow the EPA to finalize the GHG standards proposed in 2009 for new light-duty vehicles as part of the joint rulemaking with the Department of Transportation (USEPA 2009).
To regulate GHGs from passenger vehicles, EPA was required to issue an endangerment finding. The finding identifies emissions of six key GHGs—CO2, CH4, N2O, hydrofluorocarbons, perfluorocarbons, and SF6— that have been the subject of scrutiny and intense analysis for decades by scientists in the United States and around the world. The first three are applicable to the project’s GHG emissions inventory because they constitute the majority of GHG emissions and, per South Coast AQMD guidance, are the GHG emissions that should be evaluated as part of a project’s GHG emissions inventory.
US Mandatory Report Rule for GHGs (2009)
In response to the endangerment finding, the EPA issued the Mandatory Reporting of GHG Rule that requires substantial emitters of GHG emissions (large stationary sources, etc.) to report GHG emissions data.
Facilities that emit 25,000 MT or more of CO2 per year are required to submit an annual report.
Update to Corporate Average Fuel Economy Standards (2021 to 2026) The federal government issued new Corporate Average Fuel Economy (CAFE) standards in 2012 for model years 2017 to 2025, which required a fleet average of 54.5 miles per gallon in 2025. On March 30, 2020, the EPA finalized an updated CAFE and GHG emissions standards for passenger cars and light trucks and established new standards covering model years 2021 through 2026, known as the Safer Affordable Fuel Efficient (SAFE) Vehicles Final Rule for Model Years 2021 to 2026. Under SAFE, the fuel economy
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standards will increase 1.5 percent per year compared to the 5 percent per year under the CAFE standards established in 2012. Overall, SAFE requires a fleet average of 40.4 MPG for model year 2026 vehicles (85 Federal Register 24174 (April 30, 2020)).
On December 21, 2021, under direction of Executive Order (EO) 13990 issued by President Biden, the National Highway Traffic Safety Administration repealed Safer Affordable Fuel Efficient Vehicles Rule Part One, which had preempted state and local laws related to fuel economy standards. In addition, on March 31, 2022, the National Highway Traffic Safety Administration finalized new fuel standards in response to EO 13990. Fuel efficiency under the standards proposed will increase 8 percent annually for model years 2024 to 2025 and 10 percent annual for model year 2026. Overall, the new CAFE standards require a fleet average of 49 MPG for passenger vehicles and light trucks for model year 2026, which would be a 10 MPG increase relative to model year 2021 (NHTSA 2022).
EPA Regulation of Stationary Sources under the Clean Air Act (Ongoing) Pursuant to its authority under the Clean Air Act, the EPA has developed regulations for new, large, stationary sources of emissions, such as power plants and refineries. Under former President Obama’s 2013 Climate Action Plan, the EPA was directed to develop regulations for existing stationary sources as well. On June 19, 2019, the EPA issued the final Affordable Clean Energy (ACE) rule, which became effective on August 19, 2019. The ACE rule was crafted under the direction of President Trump’s Energy Independence EO. It officially rescinded the Clean Power Plan rule issued during the Obama Administration and set emissions guidelines for states in developing plans to limit CO2 emissions from coal-fired power plants. The Affordable Clean Energy rule was vacated by the United States Court of Appeals for the District of Columbia Circuit on January 19, 2021. The Biden Administration is assessing options on potential future regulations.
REGULATION OF GHG EMISSIONS ON A STATE LEVEL
Current State of California guidance and goals for reductions in GHG emissions are generally embodied in EO S-03-05 and EO B-30-15, EO B-55-18, Assembly Bill 32 (AB 32), Senate Bill 32 (SB 32), and SB 375.
Executive Order S-3-05
Executive Order S-3-05, signed June 1, 2005. Executive Order S-3-05 set the following GHG reduction targets for the State:
2000 levels by 2010
1990 levels by 2020
80 percent below 1990 levels by 2050
Assembly Bill 32, the Global Warming Solutions Act (2006) AB 32 was passed by the California state legislature on August 31, 2006, to place the state on a course toward reducing its contribution of GHG emissions. AB 32 follows the 2020 tier of emissions reduction targets
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established in EO S-03-05. CARB prepared the 2008 Scoping Plan to outline a plan to achieve the GHG emissions reduction targets of AB 32.
Executive Order B-30-15
EO B-30-15, signed April 29, 2015, set a goal of reducing GHG emissions within the state to 40 percent of 1990 levels by year 2030. EO B-30-15 also directed CARB to update the Scoping Plan to quantify the 2030 GHG reduction goal for the state and requires state agencies to implement measures to meet the interim 2030 goal as well as the long-term goal for 2050 in EO S-03-05. It also requires the Natural Resources Agency to conduct triennial updates of the California adaption strategy, “Safeguarding California”, in order to ensure climate change is accounted for in state planning and investment decisions.
Senate Bill 32 and Assembly Bill 197
In September 2016, Governor Brown signed SB 32 and AB 197 into law, making the Executive Order goal for year 2030 into a statewide mandated legislative target. AB 197 established a joint legislative committee on climate change policies and requires the CARB to prioritize direction emissions reductions rather than the market-based cap-and-trade program for large stationary, mobile, and other sources.
Executive Order B-55-18
Executive Order B-55-18, signed September 10, 2018, set a goal “to achieve carbon neutrality as soon as possible, and no later than 2045, and achieve and maintain net negative emissions thereafter.” Executive Order B-55-18 directs CARB to work with relevant state agencies to ensure that future Scoping Plans identify and recommend measures to achieve the carbon neutrality goal. The goal of carbon neutrality by 2045 is in addition to other statewide goals, meaning that not only should emissions be reduced to 80 percent below 1990 levels by 2050, but that, by no later than 2045, the remaining emissions should be offset by equivalent net removals of CO2e from the atmosphere, including through sequestration in forests, soils, and other natural landscapes.
Assembly Bill 1279
AB 1279, signed by Governor Newsom in September 2022, codified the carbon neutrality targets of EO B55-18 for year 2045 and sets a new legislative target for year 2045 of 85 percent below 1990 levels for anthropogenic GHG emissions. SB 1279 also requires CARB to update the Scoping Plan to address these new targets.
Draft 2022 Climate Change Scoping Plan
CARB adopted the 2022 Scoping Plan for Achieving Carbon Neutrality (2022 Scoping Plan) on December 15, 2022, which lays out a path to achieve carbon neutrality by 2045 or earlier and to reduce the State’s anthropogenic GHG emissions (CARB 2022). The Scoping Plan provides updates to the previously adopted 2017 Scoping Plan and addresses the carbon neutrality goals of EO B-55-18 (discussed below) and the ambitious GHG reduction target as directed by AB 1279. Previous Scoping Plans focused on specific GHG reduction targets for our industrial, energy, and transportation sectors—to meet 1990 levels by 2020, and then the more aggressive 40 percent below that for the 2030 target. The 2022 Scoping Plan updates the target of reducing anthropogenic emissions to 85 percent below 1990 levels by 2045. Carbon neutrality takes it one
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step further by expanding actions to capture and store carbon including through natural and working lands and mechanical technologies, while drastically reducing anthropogenic sources of carbon pollution at the same time.
The path forward was informed by the recent Sixth Assessment Report (AR6) of the IPCC and the measures would achieve 85 percent below 1990 levels by 2045 in accordance AB 1279. CARB’s 2022 Scoping Plan identifies strategies as shown in Table 11, Priority Strategies for Local Government Climate Action Plans, that would be most impactful at the local level for ensuring substantial process towards the State’s carbon neutrality goals.
Table 11 Priority Strategies for Local Government Climate Action Plans Priority Area Priority Strategies
Transportation Electrification
Convert local government fleets to zero-emission vehicles (ZEV) and provide EV charging at public sites.
Create a jurisdiction-specific ZEV ecosystem to support deployment of ZEVs statewide (such as building standards that exceed state building codes, permit streamlining, infrastructure siting, consumer education, preferential parking policies, and ZEV readiness plans).
VMT Reduction
Reduce or eliminate minimum parking standards.
Implement Complete Streets policies and investments, consistent with general plan circulation element requirements.
Increase access to public transit by increasing density of development near transit, improving transit service by increasing service frequency, creating bus priority lanes, reducing or eliminating fares, microtransit, etc.
Increase public access to clean mobility options by planning for and investing in electric shuttles, bike share, car share, and walking
Implement parking pricing or transportation demand management pricing strategies.
Amend zoning or development codes to enable mixed-use, walkable, transit-oriented, and compact infill development (such as increasing allowable density of the neighborhood).
Preserve natural and working lands by implementing land use policies that guide development toward infill areas and do not convert “greenfield” land to urban uses (e.g., green belts, strategic conservation easements)
Building Decarbonization
Adopt all-electric new construction reach codes for residential and commercial uses.
Adopt policies and incentive programs to implement energy efficiency retrofits for existing buildings, such as weatherization, lighting upgrades, and replacing energy-intensive appliances and equipment with more efficient systems (such as Energy Star-rated equipment and equipment controllers).
Adopt policies and incentive programs to electrify all appliances and equipment in existing buildings such as appliance rebates, existing building reach codes, or time of sale electrification ordinances .
Facilitate deployment of renewable energy production and distribution and energy storage on privately owned land uses (e.g., permit streamlining, information sharing) .
Deploy renewable energy production and energy storage directly in new public projects and on existing public facilities (e.g., solar photovoltaic systems on rooftops of municipal buildings and on canopies in public parking lots, battery storage systems in municipal buildings) .
Source: CARB 2022
Based on Appendix D of the 2022 CARB Climate Change Scoping Plan, for residential and mixed-use development projects, CARB recommends first demonstrating that these land use development projects are aligned with State climate goals based on the attributes of land use development that reduce operational
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GHG emissions while simultaneously advancing fair housing. Attributes that accommodate growth in a manner consistent with the GHG and equity goals of SB 32 have all the following attributes:
Transportation Electrification
Provide EV charging infrastructure that, at a minimum, meets the most ambitious voluntary standards in the California Green Building Standards Code at the time of project approval. VMT Reduction
Is located on infill sites that are surrounded by existing urban uses and reuses or redevelops previously undeveloped or underutilized land that is presently served by existing utilities and essential public services (e.g., transit, streets, water, sewer). Does not result in the loss or conversion of the State’s natural and working lands; Consists of transit-supportive densities (minimum of 20 residential dwelling units/acre), or is in proximity to existing transit stops (within a half mile), or satisfies more detailed and stringent criteria specified in the region’s Sustainable Communities Strategy (SCS); Reduces parking requirements by:
- Eliminating parking requirements or including maximum allowable parking ratios (i.e., the ratio of parking spaces to residential units or square feet); or - Providing residential parking supply at a ratio of <1 parking space per dwelling unit; or - For multifamily residential development, requiring parking costs to be unbundled from costs to rent or own a residential unit.
At least 20 percent of the units are affordable to lower-income residents; Result in no net loss of existing affordable units.
Building Decarbonization
Use all electric appliances without any natural gas connections and does not use propane or other fossil fuels for space heating, water heating, or indoor cooking (CARB 2022).
If the first approach to demonstrating consistency is not applicable (such as in the case of this school modernization project), the second approach to project-level alignment with state climate goals is to achieve net zero GHG emissions. The third approach to demonstrating project-level alignment with state climate goals is to align with GHG thresholds of significance, which many local air quality management (AQMDs) and air pollution control districts (APCDs) have developed or adopted (CARB 2022).
Senate Bill 375
In 2008, SB 375, the Sustainable Communities and Climate Protection Act, was adopted to connect the GHG emissions reductions targets established in the 2008 Scoping Plan for the transportation sector to local land
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use decisions that affect travel behavior. Its intent is to reduce GHG emissions from light-duty trucks and automobiles (excludes emissions associated with goods movement) by aligning regional long-range transportation plans, investments, and housing allocations to local land use planning to reduce VMT and vehicle trips. Specifically, SB 375 required CARB to establish GHG emissions reduction targets for each of the 18 metropolitan planning organizations (MPO). The Southern California Association of Governments (SCAG) is the MPO for the Southern California region, which includes the counties of Los Angeles, Orange, San Bernardino, Riverside, Ventura, and Imperial.
Pursuant to the recommendations of the Regional Transportation Advisory Committee, CARB adopted per capita reduction targets for each of the MPOs rather than a total magnitude reduction target. SCAG’s targets are an 8 percent per capita reduction from 2005 GHG emission levels by 2020 and a 13 percent per capita reduction from 2005 GHG emission levels by 2035 (CARB 2010). The 2020 targets are smaller than the 2035 targets because a significant portion of the built environment in 2020 is defined by decisions that have already been made. In general, the 2020 scenarios reflect that more time is needed for large land use and transportation infrastructure changes. Most of the reductions in the interim are anticipated to come from improving the efficiency of the region’s transportation network. The targets would result in 3 MMTCO2e of reductions by 2020 and 15 MMTCO2e of reductions by 2035. Based on these reductions, the passenger vehicle target in CARB’s Scoping Plan (for AB 32) would be met (CARB 2010). 2017 Update to the SB 375 Targets
CARB is required to update the targets for the MPOs every eight years. CARB adopted revised SB 375 targets for the MPOs in March 2018. The updated targets became effective in October2018. All SCSs adopted after October 1, 2018, are subject to these new targets. CARB’s updated SB 375 targets for the SCAG region were an 8 percent per capita GHG reduction in 2020 from 2005 levels (unchanged from the 2010 target) and a 19 percent per capita GHG reduction in 2035 from 2005 levels (compared to the 2010 target of 13 percent) (CARB 2018).
The targets consider the need to further reduce VMT, as identified in the 2017 Scoping Plan Update (for SB 32), while balancing the need for additional and more flexible revenue sources to incentivize positive planning and action toward sustainable communities. Like the 2010 targets, the updated SB 375 targets are in units of “percent per capita” reductions in GHG emissions from automobiles and light trucks relative to 2005; this excludes reductions anticipated from implementation of state technology and fuels strategies and any potential future state strategies, such as statewide road user pricing. The proposed targets call for greater percapita GHG emission reductions from SB 375 than are currently in place, which for 2035 translate into proposed targets that either match or exceed the emission reduction levels in the MPOs’ currently adopted SCSs to achieve the SB 375 targets. CARB foresees that the additional GHG emissions reductions in 2035 may be achieved from land use changes, transportation investment, and technology strategies (CARB 2018).
SCAG’s Regional Transportation Plan / Sustainable Communities Strategy SB 375 requires each MPO to prepare a sustainable communities strategy in its regional transportation plan.
For the SCAG region, the 2020-2045 RTP/SCS (Connect SoCal) was adopted on September 3, 2020, and is an update to the 2016-2040 RTP/SCS. In general, the SCS outlines a development pattern for the region that,
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when integrated with the transportation network and other transportation measures and policies, would reduce vehicle miles traveled from automobiles and light duty trucks and thereby reduce GHG emissions from these sources.
Connect SoCal focuses on the continued efforts of the previous RTP/SCSs to integrate transportation and land use strategies in development of the SCAG region through horizon year 2045 (SCAG 2020). Connect SoCal forecasts that the SCAG region will meet its GHG per capita reduction targets of 8 percent by 2020 and 19 percent by 2035. Additionally, Connect SoCal also forecasts that implementation of the plan will reduce VMT per capita in year 2045 by 4.1 percent compared to baseline conditions for that year. Connect SoCal includes a “Core Vision” that centers on maintaining and better managing the transportation network for moving people and goods while expanding mobility choices by locating housing, jobs, and transit closer together and increasing investments in transit and complete streets (SCAG 2020).
Transportation Sector Specific Regulations
Assembly Bill 1493
California vehicle GHG emission standards were enacted under AB 1493 (Pavley I). Pavley I is a clean-car standard that reduces GHG emissions from new passenger vehicles (light-duty auto to medium-duty vehicles) from 2009 through 2016 and is anticipated to reduce GHG emissions from new passenger vehicles by 30 percent in 2016. California implements the Pavley I standards through a waiver granted to California by the EPA. In 2012, the EPA issued a Final Rulemaking that sets even more stringent fuel economy and GHG emissions standards for model years 2017 through 2025 light-duty vehicles. (See also the discussion on the update to the Corporate Average Fuel Economy standards at the beginning of this Section 5.5.2 under “Federal.”) In January 2012, CARB approved the Advanced Clean Cars program (formerly known as Pavley II) for model years 2017 through 2025. The program combines the control of smog, soot, and GHGs with requirements for greater numbers of ZE vehicles into a single package of standards. Under California’s Advanced Clean Car program, by 2025 new automobiles will emit 34 percent less GHG emissions and 75 percent less smog-forming emissions.
Executive Order S-01-07
On January 18, 2007, the state set a new LCFS for transportation fuels sold in the state. Executive Order S-01-07 sets a declining standard for GHG emissions measured in CO2e gram per unit of fuel energy sold in California. The LCFS required a reduction of 2.5 percent in the carbon intensity of California’s transportation fuels by 2015 and a reduction of at least 10 percent by 2020. The standard applies to refiners, blenders, producers, and importers of transportation fuels, and uses market-based mechanisms to allow these providers to choose how they reduce emissions during the “fuel cycle” using the most economically feasible methods.
Executive Order B-16-2012
On March 23, 2012, the state identified that CARB, the California Energy Commission (CEC), the Public Utilities Commission, and other relevant agencies worked with the Plug-in Electric Vehicle Collaborative and the California Fuel Cell Partnership to establish benchmarks to accommodate ZE vehicles in major
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metropolitan areas, including infrastructure to support them (e.g., electric vehicle charging stations). The executive order also directed the number of ZE vehicles in California’s state vehicle fleet to increase through the normal course of fleet replacement so that at least 10 percent of fleet purchases of light-duty vehicles are ZE by 2015 and at least 25 percent by 2020. The executive order also establishes a target for the transportation sector of reducing GHG emissions to 80 percent below 1990 levels.
Executive Order N-79-20
On September 23, 2020, Governor Newsom signed Executive Order N-79-20, whose goal is that 100 percent of in-state sales of new passenger cars and trucks will be ZE by 2035. Additionally, the fleet goals for trucks are that 100 percent of drayage trucks are ZE by 2035, and 100 percent of medium- and heavy-duty vehicles in the state are ZE by 2045, where feasible. The Executive Order’s goal for the State is to transition to 100 percent ZE off-road vehicles and equipment by 2035, where feasible.
Renewables Portfolio: Carbon Neutrality Regulations
Senate Bills 1078, 107, and X1-2 and Executive Order S-14-08 A major component of California’s Renewable Energy Program is the renewables portfolio standard established under Senate Bills 1078 (Sher) and 107 (Simitian). Under the RPS, certain retail sellers of electricity were required to increase the amount of renewable energy each year by at least 1 percent in order to reach at least 20 percent by December 30, 2010. Executive Order S-14-08, signed in November 2008, expanded the state’s renewable energy standard to 33 percent renewable power by 2020. This standard was adopted by the legislature in 2011 (SB X1-2). Renewable sources of electricity include wind, small hydropower, solar, geothermal, biomass, and biogas. The increase in renewable sources for electricity production will decrease indirect GHG emissions from development projects because electricity production from renewable sources is generally considered carbon neutral.
Senate Bill 350
Senate Bill 350 (de Leon) was signed into law September 2015 and establishes tiered increases to the RPS—40 percent by 2024, 45 percent by 2027, and 50 percent by 2030. SB 350 also set a new goal to double the energy-efficiency savings in electricity and natural gas through energy efficiency and conservation measures.
Senate Bill 100
On September 10, 2018, Governor Brown signed SB 100. Under SB 100, the RPS for public-owned facilities and retail sellers consist of 44 percent renewable energy by 2024, 52 percent by 2027, and 60 percent by 2030.
SB 100 also established a new RPS requirement of 50 percent by 2026. Furthermore, the bill establishes an overall state policy that eligible renewable energy resources and zero-carbon resources supply 100 percent of all retail sales of electricity to California end-use customers and 100 percent of electricity procured to serve all state agencies by December 31, 2045. Under the bill, the state cannot increase carbon emissions elsewhere in the western grid or allow resource shuffling to achieve the 100 percent carbon-free electricity target.
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Senate Bill 1020
Senate Bill 1020 was signed into law on September 16, 2022. It requires renewable energy and zero-carbon resources to supply 90 percent of all retail electricity sales by 2035 and 95 percent by 2040. Additionally, SB 1020 requires all state agencies to procure 100 percent of electricity from renewable energy and zero-carbon resources by 2035.
Energy Efficiency Regulations
California Building Code: Building Energy Efficiency Standards Energy conservation standards for new residential and nonresidential buildings were adopted by the California Energy Resources Conservation and Development Commission (now the CEC) in June 1977 (Title 24, Part 6, of the California Code of Regulations [CCR]). Title 24 requires the design of building shells and building components to conserve energy. The standards are updated periodically to allow for consideration and possible incorporation of new energy efficiency technologies and methods.
On August 11, 2021, the CEC adopted the 2022 Building Energy Efficiency Standards, which were subsequently approved by the California Building Standards Commission in December 2021. The 2022 standards went into effect on January 1, 2023, replacing the existing 2019 standards. The 2022 standards would require mixed-fuel single-family homes to be electric-ready to accommodate replacement of gas appliances with electric appliances. In addition, the new standards also include prescriptive photovoltaic system and battery requirements for high-rise, multifamily buildings (i.e., more than three stories) and noncommercial buildings such as hotels, offices, medical offices, restaurants, retail stores, schools, warehouses, theaters, and convention centers (CEC 2021).
California Building Code: CALGreen
On July 17, 2008, the California Building Standards Commission adopted the nation’s first green building standards. The California Green Building Standards Code (24 CCR, Part 11, known as “CALGreen”) was adopted as part of the California Building Standards Code. CALGreen established planning and design standards for sustainable site development, energy efficiency (in excess of the California Energy Code requirements), water conservation, material conservation, and internal air contaminants.13 The mandatory provisions of CALGreen became effective January 1, 2011. In 2021, the CEC approved the 2022 CALGreen, which went into effect on January 1, 2023, replacing the existing 2019 standards. 2006 Appliance Efficiency Regulations
The 2006 Appliance Efficiency Regulations (20 CCR §§ 1601–1608) were adopted by the CEC on October 11, 2006, and approved by the California Office of Administrative Law on December 14, 2006. The regulations include standards for both federally regulated appliances and non–federally regulated appliances. 13 The green building standards became mandatory in the 2010 edition of the code.
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Though these regulations are now often viewed as “business as usual,” they exceed the standards imposed by all other states, and they reduce GHG emissions by reducing energy demand.
Solid Waste Diversion Regulations
AB 939: Integrated Waste Management Act of 1989
California’s Integrated Waste Management Act of 1989 (AB 939, Public Resources Code §§ 40050 et seq.) set a requirement for cities and counties throughout the state to divert 50 percent of all solid waste from landfills by January 1, 2000, through source reduction, recycling, and composting. In 2008, the requirements were modified to reflect a per capita requirement rather than tonnage. To help achieve this, the act requires that each city and county prepare and submit a source reduction and recycling element. AB 939 also established the goal for all California counties to provide at least 15 years of ongoing landfill capacity.
AB 341
AB 341 (Chapter 476, Statutes of 2011) increased the statewide goal for waste diversion to 75 percent by 2020 and requires recycling of waste from commercial and multifamily residential land uses. Section 5.408 of CALGreen also requires that at least 65 percent of the nonhazardous construction and demolition waste from nonresidential construction operations be recycled and/or salvaged for reuse.
AB 1327
The California Solid Waste Reuse and Recycling Access Act (AB 1327, Public Resources Code §§ 42900 et seq.) requires areas to be set aside for collecting and loading recyclable materials in development projects. The act required the California Integrated Waste Management Board to develop a model ordinance for adoption by any local agency requiring adequate areas for collection and loading of recyclable materials as part of development projects. Local agencies are required to adopt the model or an ordinance of their own.
AB 1826
In October of 2014, Governor Brown signed AB 1826 requiring businesses to recycle their organic waste on and after April 1, 2016, depending on the amount of waste they generate per week. This law also requires that on and after January 1, 2016, local jurisdictions across the state implement an organic waste recycling program to divert organic waste generated by businesses and multifamily residential dwellings with five or more units. Organic waste means food waste, green waste, landscape and pruning waste, nonhazardous wood waste, and food-soiled paper waste that is mixed with food waste.
Water Efficiency Regulations
SBX7-7
The 20x2020 Water Conservation Plan was issued by the Department of Water Resources (DWR) in 2010 pursuant to Senate Bill 7, which was adopted during the 7th Extraordinary Session of 2009–2010 and therefore dubbed “SBX7-7.” SBX7-7 mandated urban water conservation and authorized the DWR to prepare a plan implementing urban water conservation requirements (20x2020 Water Conservation Plan). In addition, it required agricultural water providers to prepare agricultural water management plans, measure
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water deliveries to customers, and implement other efficiency measures. SBX7-7 required urban water providers to adopt a water conservation target of 20 percent reduction in urban per capita water use by 2020 compared to 2005 baseline use.
AB 1881: Water Conservation in Landscaping Act
The Water Conservation in Landscaping Act of 2006 (AB 1881) requires local agencies to adopt the updated DWR model ordinance or an equivalent. AB 1881 also requires the CEC to consult with the DWR to adopt, by regulation, performance standards and labeling requirements for landscape irrigation equipment, including irrigation controllers, moisture sensors, emission devices, and valves to reduce the wasteful, uneconomic, inefficient, or unnecessary consumption of energy or water.
Short-Lived Climate Pollutant Reduction Strategy
Senate Bill 1383
On September 19, 2016, the Governor signed SB 1383 to supplement the GHG reduction strategies in the Scoping Plan to consider short-lived climate pollutants, including black carbon and CH4. Black carbon is the light-absorbing component of fine particulate matter produced during the incomplete combustion of fuels.
SB 1383 required the state board, no later than January 1, 2018, to approve and begin implementing a comprehensive strategy to reduce emissions of short-lived climate pollutants to achieve a reduction in methane by 40 percent, hydrofluorocarbon gases by 40 percent, and anthropogenic black carbon by 50 percent below 2013 levels by 2030. The bill also established targets for reducing organic waste in landfills.
On March 14, 2017, CARB adopted the Short-Lived Climate Pollutant Reduction Strategy, which identifies the state’s approach to reducing anthropogenic and biogenic sources of short-lived climate pollutants.
Anthropogenic sources of black carbon include on- and off-road transportation, residential wood burning, fuel combustion (charbroiling), and industrial processes. According to CARB, ambient levels of black carbon in California are 90 percent lower than in the early 1960s, despite the tripling of diesel fuel use (CARB 2017a). In-use on-road rules were expected to reduce black carbon emissions from on-road sources by 80 percent between 2000 and 2020. South Coast AQMD is one of the air districts that requires air pollution control technologies for chain-driven broilers, which reduces particulate emissions from these charbroilers by over 80 percent (CARB 2017a). Additionally, South Coast AQMD Rule 445 limits installation of new fireplaces in the South Coast Air Basin.
Existing Conditions
CALIFORNIA’S GREENHOUSE GAS SOURCES AND RELATIVE CONTRIBUTION In 2021, the statewide GHG emissions inventory was updated for 2000 to 2019 emissions using the GWPs in IPCC’s AR4 (IPCC 2013). Based on these GWPs, California produced 418.2 MMTCO2e GHG emissions in 2019. California’s transportation sector was the single largest generator of GHG emissions, producing 39.7 percent of the state’s total emissions. Industrial sector emissions made up 21.1 percent, and electric power generation made up 14.1 percent of the state’s emissions inventory. Other major sectors of GHG emissions include commercial and residential (10.5 percent), agriculture and forestry (7.6 percent), high GWP (4.9 percent), and recycling and waste (2.1 percent) (CARB 2021).
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
Since the peak level in 2004, California’s GHG emission shave generally followed a decreasing trend. In 2016, California statewide GHG emissions dropped below the AB 32 target for year 2020 of 431 MMTCO2e and have remained below this target since then. In 2019, emissions from routine GHG-emitting activities statewide were almost 13 MMTCO2e lower than the AB 32 target for year 2020. Per-capita GHG emissions in California have dropped from a 2001 peak of 14.0 MTCO2e per person to 10.5 MTCO2e per person in 2019, a 25 percent decrease.
Transportation emissions continued to decline in 2019 statewide as they had done in 2018, with even more substantial reductions due to a significant increase in renewable diesel. Since 2008, California’s electricity sector has followed an overall downward trend in emissions. In 2019, solar power generation continued its rapid growth since 2013. Emissions from high-GWP gases comprised 4.9 percent of California’s emissions in 2019. This continues the increasing trend as the gases replace ozone-depleting substances being phased out under the 1987 Montreal Protocol. Overall trends in the inventory also demonstrate that the carbon intensity of California’s economy (the amount of carbon pollution per million dollars of gross domestic product) has declined 45 percent since the 2001 peak, though the state’s gross domestic product grew 63 percent during this period (CARB 2021).
Thresholds of Significance
The CEQA Guidelines recommend that a lead agency consider the following when assessing the significance of impacts from GHG emissions on the environment:
1. The extent to which the project may increase (or reduce) GHG emissions as compared to the existing environmental setting;
2. Whether the project emissions exceed a threshold of significance that the lead agency determines applies to the project;
3. The extent to which the project complies with regulations or requirements adopted to implement an adopted statewide, regional, or local plan for the reduction or mitigation of GHG emissions.14
SOUTH COAST AQMD WORKING GROUP
To provide guidance to local lead agencies on determining significance for GHG emissions in their CEQA documents, South Coast AQMD convened a GHG CEQA Significance Threshold Working Group (Working Group). The South Coast AQMD Working Group (Meeting No. 15) identified a tiered approach for evaluating GHG emissions for development projects where South Coast AQMD is not the lead agency (South Coast AQMD 2010):
14 The Governor’s Office of Planning and Research recommendations include a requirement that such a plan must be adopted through a public review process and include specific requirements that reduce or mitigate the project’s incremental contribution of GHG emissions. If there is substantial evidence that the possible effects of a particular project are still cumulatively considerable, notwithstanding compliance with the adopted regulations or requirements, an EIR must be prepared for the project.
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
Tier 1. If a project is exempt from CEQA, project-level and cumulative GHG emissions are less than significant.
Tier 2. If the project complies with a GHG emissions reduction plan or mitigation program that avoids or substantially reduces GHG emissions in the project’s geographic area (i.e., city or county), project-level and cumulative GHG emissions are less than significant. Tier 3. If GHG emissions are less than the screening-level threshold, project-level and cumulative GHG emissions are less than significant.
For projects that are not exempt or where no qualifying GHG reduction plans are directly applicable, South Coast AQMD requires an assessment of GHG emissions. The South Coast AQMD Working Group identified a screening-level threshold of 3,000 MTCO2e annually for all land use types or the following land-use-specific thresholds: 1,400 MTCO2e for commercial projects, 3,500 MTCO2e for residential projects, or 3,000 MTCO2e for mixed-use projects. These bright-line thresholds are based on a review of the Governor’s Office of Planning and Research database of CEQA projects. Based on their review of 711 CEQA projects, 90 percent of CEQA projects would exceed the bright-line thresholds identified above. Therefore, projects that do not exceed the bright-line threshold would have a nominal, and therefore, less than cumulatively considerable impact on GHG emissions:
Tier 4. If emissions exceed the screening threshold, a more detailed review of the project’s GHG emissions is warranted.
The South Coast AQMD Working Group has identified an efficiency target for projects that exceed the screening threshold of 4.8 MTCO2e per year per service population (MTCO2e/year/SP) for project-level analyses and 6.6 MTCO2e/year/SP for plan level projects (e.g., program-level projects such as general plans) for the year 2020.15 The per capita efficiency targets are based on the AB 32 GHG reduction target and 2020 GHG emissions inventory prepared for CARB’s 2008 Scoping Plan.
The bright-line screening-level criterion of 3,000 MTCO2e/yr is used as the significance threshold for this project. Therefore, if the project operation-phase emissions exceed the 3,000 MTCO2e/yr threshold, GHG emissions would be considered potentially significant in the absence of mitigation measures. 15 It should be noted that the Working Group also considered efficiency targets for 2035 for the first time in this Working Group meeting.
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
BIBLIOGRAPHY
Bay Area Air Quality Management District (BAAQMD). 2017, May. California Environmental Quality Act Air Quality Guidelines. https://www.baaqmd.gov/~/media/files/planning-andresearch/ceqa/ceqa_guidelines_may2017-pdf.pdf?la=en.
California Air Pollution Control Officers Association (CAPCOA). 2022. California Emissions Estimator Model (CalEEMod). Version 2022.1.0. Prepared by: ICF in collaboration with Sacramento Metropolitan Air Quality Management District.
California Air Resources Board (CARB). 1999. California Air Resources Board (CARB). Final Staff Report:
Update to the Toxic Air Contaminant List. https://www.arb.ca.gov/toxics/finalreport.pdf ———. 2010, September. Staff Report Proposed Regional Greenhouse Gas Emission Reduction Targets for Automobiles and Light Trucks Pursuant to Senate Bill 375. https://ww3.arb.ca.gov/board/res/2010/res10-31.pdf.
———. 2016, October 1. Ambient Air Quality Standards. https://ww2.arb.ca.gov/sites/default/files/2020- 07/aaqs2.pdf.
———. 2017a, March 14. Final Proposed Short-Lived Climate Pollutant Reduction Strategy. https://ww2.arb.ca.gov/sites/default/files/2018-12/final_slcp_report%20Final%202017.pdf. ———. 2017b, November. California’s 2017 Climate Change Scoping Plan: The Strategy for Achieving California’s 2030 Greenhouse Gas Target.
https://www.arb.ca.gov/cc/scopingplan/scoping_plan_2017.pdf. ———. 2018, February. Proposed Update to the SB 375 Greenhouse Gas Emission Reduction Targets. https://www.arb.ca.gov/cc/sb375/sb375_target_update_final_staff_report_feb2018.pdf. ———. 2019, July 25. California and major automakers reach groundbreaking framework agreement on clean emission standards. https://ww2.arb.ca.gov/news/california-and-major-automakers-reachgroundbreaking-framework-agreement-clean-emission. ______. 2022, December 15. CARB Draft Scoping Plan: AB32 Source Emissions Initial Modeling Results. https://ww2.arb.ca.gov/our-work/programs/ab-32-climate-change-scoping-plan/2022-scopingplan-documents ———. 2023a, January 20 (accessed). Area Designations Maps/State and National. https://ww2.arb.ca.gov/resources/documents/maps-state-and-federal-area-designations. ______. 2023b, February 20 (accessed). Air Pollution Data Monitoring Cards (2016, 2017, 2018, 2019, and 2020). https://www.arb.ca.gov/adam/topfour/topfour1.php
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
———. 2023c, February 20 (accessed). Common Air Pollutants. https://ww2.arb.ca.gov/resources/common -air-pollutants.
California Energy Commission (CEC). 2021, May 19. Amendments to the Building Energy Efficiency Standards (2022 Energy Code) Draft Environmental Report. CEC-400-2021-077-D.
Intergovernmental Panel on Climate Change (IPCC). 1995. Second Assessment Report: Climate Change 1995. https://www.ipcc.ch/site/assets/uploads/2018/02/ipcc_sar_wg_I_full_report.pdf. ———. 2001. Third Assessment Report: Climate Change 2001. New York: Cambridge University Press. https://www.ipcc.ch/site/assets/uploads/2018/03/WGI_TAR_full_report.pdf. ———. 2007. Fourth Assessment Report: Climate Change 2007. New York: Cambridge University Press. https://www.ipcc.ch/site/assets/uploads/2018/02/ar4_syr_full_report.pdf. ———. 2013. Fifth Assessment Report: Climate Change 2013. New York: Cambridge University Press. https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_all_final.pdf.
National Highway Traffic Safety Administration. 2022, April 1. USDOT Announces New Vehicle Fuel Economy Standards for Model year 2024-2026. https://www.nhtsa.gov/press-releases/usdotannounces-new-vehicle-fuel-economy-standards-model-year-2024-2026, accessed on July 27, 2022.
South Coast Air Quality Management District (South Coast AQMD). 1992. Federal Attainment Plan for Carbon Monoxide.
———. 1993. California Environmental Quality Act Air Quality Handbook. ———. 2003, August. 2003 Air Quality Management Plan. Appendix V. https://www.aqmd.gov/home/airquality/clean-air-plans/air-quality-mgt-plan/2003-aqmp. ———. 2005, May. Guidance Document for Addressing Air Quality Issues in General Plans and Local Planning. http://www.aqmd.gov/docs/default-source/planning/air-quality-guidance/complete -guidance-document.pdf.
———. 2008, July. Final Localized Significance Threshold Methodology. ———. 2009, November 19. GHG Meeting 14 Main Presentation. Greenhouse Gases (GHG) CEQA Significance Threshold Working Group. http://www.aqmd.gov/docs/defaultsource/ceqa/handbook/greenhouse-gases-(ghg)-ceqa -significance-thresholds/year-2008-2009/ghg-meeting-14/ghg-meeting-14-main -presentation.pdf?sfvrsn=2.
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
———. 2011. Fact Sheet for Applying CalEEMod to Localized Significance Thresholds. http://www.aqmd.gov/docs/default-source/ceqa/handbook/localized-significance-thresholds/ caleemod-guidance.pdf?sfvrsn=2.
———. 2010, September 28. Greenhouse Gases (GHG) CEQA Significance Thresholds Working Group Meeting 15. http://www.aqmd.gov/docs/default-source/ceqa/handbook/greenhouse-gases-(ghg)- ceqa-significance-thresholds/year-2008-2009/ghg-meeting-15/ghg-meeting-15-mainpresentation.pdf. ———. 2012, May 4. Final 2012 Lead State Implementation Plan: Los Angeles County. http://www3.aqmd.gov/hb/attachments/2011-2015/2012May/2012-May4-030.pdf. ———. 2013, February. 2012 Final Air Quality Management Plan. https://www.aqmd.gov/docs/defaultsource/clean-air-plans/air-quality-management-plans/2012-air-quality-management-plan/final-2012- aqmp-(february-2013)/main-document-final-2012.pdf.
———. 2015a. Health Effects of Air Pollution. http://www.aqmd.gov/docs/default-source/ publications/brochures/the-health-effects-of-air-pollution-brochure.pdf. ———. 2015b, October. “Blueprint for Clean Air: 2016 AQMP White Paper.” 2016 AQMP White Papers Web Page. https://www.aqmd.gov/docs/default-source/Agendas/aqmp/white-paper-working -groups/wp-blueprint-final.pdf?sfvrsn=2.
———. 2019, April (revised). South Coast AQMD Air Quality Significance Thresholds. http://www.aqmd.gov/docs/default-source/ceqa/handbook/scaqmd-air-quality-significancethresholds.pdf. ———. 2021a, August. Final Report, Multiple Air Toxics Exposure Study V (MATES V). http://www.aqmd.gov/home/air-quality/air-quality-studies/health-studies/mates-v. ———. 2021b, October. Draft Final 2021 Redesignation Request and Maintenance Plan for the 2006 and 1997 24-Hour PM2.5 Standards for South Coast Air Basin. https://ww2.arb.ca.gov/sites/default/files/2021-10/draft-final-pm2-5-redesignation-request-andmaintenance-plan.pdf ———. 2022, December. Final 2022 Air Quality Management Plan. https://www.scaqmd.gov/home/airquality/clean-air-plans/2022-aqmp-archive Southern California Association of Governments (SCAG). 2020, September 3. Connect SoCal Plan: The 2020-2045 Regional Transportation Plan / Sustainable Communities Strategy of The Southern California Association of Governments. https://www.connectsocal.org/Pages/Connect-SoCal-FinalPlan.aspx.
US Environmental Protection Agency (USEPA). 2009, December. EPA: Greenhouse Gases Threaten Public Health and the Environment. Science overwhelmingly shows greenhouse gas concentrations at
AIR QUALITY AND GREENHOUSE GAS BACKGROUND AND MODELING DATA
unprecedented levels due to human activity.
https://archive.epa.gov/epapages/newsroom_archive/newsreleases/08d11a451131bca58525768500 5bf252.html.
———. 2022, January 21 (accessed). Overview of Greenhouse Gases. http://www3.epa.gov/climatechange/ghgemissions/gases.html. ———. 2023, January 20 (accessed). Criteria Air Pollutants. https://www.epa.gov/criteria-air-pollutants.
Western Regional Climate Center (WRCC). 2023, February 2 (accessed). Period of Record Monthly Climate Summary, 08/01/1989 to 06/09/2016. Anaheim, California ([Station ID] 040192). Western US Climate Summaries. https://wrcc.dri.edu/cgi-bin/cliMAIN.pl?ca0192.
N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
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Appendix
February 2025
Appendix B Cultural Resource – Records Search
South Central Coastal Information Center
California State University, Fullerton
Department of Anthropology MH-426
800 North State College Boulevard
Fullerton, CA 92834-6846
657.278.5395
[email protected]
_____________________________________________________________________________ 4/26/2023 SCCIC File #: 24642.10802
Re: Record Search Results for the Norm Ross Sports Park Joint Use Project The South Central Coastal Information Center received your records search request for the project area referenced above, located on the Los Alamitos and Anaheim, CA USGS 7.5’ quadrangle(s). The following summary reflects the results of the records search for the project area and a ½-mile radius. The search includes a review of all recorded archaeological and built-environment resources as well as a review of cultural resource reports on file. In addition, the California Points of Historical Interest (SPHI), the California Historical Landmarks (SHL), the California Register of Historical Resources (CAL REG), the National Register of Historic Places (NRHP), and the California State Built Environment Resources Directory (BERD) listings were reviewed for the above referenced project site and a ¼-mile radius. Due to the sensitive nature of cultural resources, archaeological site locations are not released.
RECORDS SEARCH RESULTS SUMMARY
Archaeological Resources*
(*see Recommendations section)
Within project area: 0
Within project radius: 0
Built-Environment Resources Within project area: 0
Within project radius: 2
Reports and Studies Within project area: 0
Within project radius: 3
OHP Built Environment Resources
Directory (BERD) 2022
Within project area: 0
Within ¼-mile radius: 3
California Points of Historical
Interest (SPHI) 2022
Within project area: 0
Within ¼-mile radius: 0
California Historical Landmarks
(SHL) 2022
Within project area: 0
Within ¼-mile radius: 0
California Register of Historical
Resources (CAL REG) 2022
Within project area: 0
Within ¼-mile radius: 0
National Register of Historic Places
(NRHP) 2022
Within project area: 0
Within ¼-mile radius: 0
HISTORIC MAP REVIEW - Anaheim, CA (1896, 1942) and Downey 1943 15’ USGS historic maps indicate that in 1896 there was one road within the project area. There were three roads and three building within the project search radius which was located within the historic place name of Los Alamitos. In 1942, there was one road and one building within the project area. There were several additional roads and buildings within the project search radius. Major road names included Stanton Avenue, Katella Avenue. The Southern Pacific Los Alamitos Branch rail road ran through the western and northern portions of the project search radius. The Pacific Electric rail line ran northeast of the project area.
RECOMMENDATIONS
*When we report that no archaeological resources are recorded in your project area or within a specified radius around the project area; that does not necessarily mean that nothing is there. It may simply mean that the area has not been studied and/or that no information regarding the archaeological sensitivity of the property has been filed at this office. The reported records search result does not preclude the possibility that surface or buried artifacts might be found during a survey of the property or ground-disturbing activities.
The archaeological sensitivity of the project location is unknown because there are no previous studies for the subject property. Additionally, the natural ground-surface appears to be obscured by urban development; consequently, surface artifacts would not be visible during a survey. While there are currently no recorded archaeological sites within the project area, buried resources could potentially be unearthed during project activities. Therefore, customary caution and a halt-work condition should be in place for all ground-disturbing activities. In the event that any evidence of cultural resources is discovered, all work within the vicinity of the find should stop until a qualified archaeological consultant can assess the find and make recommendations. Moving or extraction of potential cultural resources should not be attempted by anyone other than a qualified cultural resources consultant. It is also recommended that the Native American Heritage Commission be consulted to identify if any additional traditional cultural properties or other sacred sites are known to be in the area. The NAHC may also refer you to local tribes with particular knowledge of potential sensitivity. The NAHC and local tribes may offer additional recommendations to what is provided here and may request an archaeological monitor. Finally, if the built-environment resources on the property are 45 years or older, a qualified architectural historian should be retained to study the property and make recommendations regarding those structures.
For your convenience, you may find a professional consultant**at www.chrisinfo.org. Any resulting reports by the qualified consultant should be submitted to the South Central Coastal Information Center as soon as possible. **The SCCIC does not endorse any particular consultant and makes no claims about the qualifications of any person listed.
Each consultant on this list self-reports that they meet current professional standards.
If you have any questions regarding the results presented herein, please contact the office at 657.278.5395 Monday through Thursday 9:00 am to 3:30 pm. Should you require any additional information for the above referenced project, reference the SCCIC number listed above when making inquiries. Requests made after initial invoicing will result in the preparation of a separate invoice.
Thank you for using the California Historical Resources Information System, Isabela Kott
Assistant Coordinator, GIS Program Specialist
Due to processing delays and other factors, not all of the historical resource reports and resource records that have been submitted to the Office of Historic Preservation are available via this records search. Additional information may be available through the federal, state, and local agencies that produced or paid for historical resource management work in the search area. Additionally, Native American tribes have historical resource information not in the California Historical Resources Information System (CHRIS) Inventory, and you should contact the California Native American Heritage Commission for information on local/regional tribal contacts.
The California Office of Historic Preservation (OHP) contracts with the California Historical Resources Information System’s (CHRIS) regional Information Centers (ICs) to maintain information in the CHRIS inventory and make it available to local, state, and federal agencies, cultural resource professionals, Native American tribes, researchers, and the public. Recommendations made by IC coordinators or their staff regarding the interpretation and application of this information are advisory only. Such recommendations do not necessarily represent the evaluation or opinion of the State Historic Preservation Officer in carrying out the OHP’s regulatory authority under federal and state law.
N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
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C I T Y O F S T A N T O N
Appendix
February 2025
Appendix C Geotechnical Report
John R. Byerly
N C O R P O R A T E D
GEOTECHNICAL INVESTIGATION
APRIL 14, 2023
NORM ROSS SPORTS COMPLEX
PROPOSED PARK BUILDING AND BRIDGE OVER STORM CHANNEL
11111 CEDAR STREET
DISTRIBUTION:
STANTON, CALIFORNIA
CLIENT:
PBK ARCHITECTS
600 ANTON BOULEVARD, SUITE 1375
COSTA MESA, CALIFORNIA 92626
ATTENTION: JOSE' VALLARTA, LEED™ GA
(1) PBK ARCHITECTS
RPT. NO.: 7650-a
FILE NO.: S-14556
GEOTECHNICAL ENGINEERS • TESTING AND INSPECTION
2257 South Lilac Ave., Bloomington, CA 92316-2903
Bloomington (909) 877-1324 Riverside (909) 783-1910 Fax (909) 877-5210 John R. Byerly
N C O R P O R A T E D
TABLE OF CONTENTS
SECTION PAGE NO.
Introduction.. ..................................................... ............................................... 1 Project Description........................................................................................... 2 Site Conditions................................................................................................. 2 Field and Laboratory Investigation . ... . . . . . . .. . . . .. .. . . .. . . . . . .. . . . . . . . .. . . . . .. ... . . . . . . . .. .. . .. . .. . . 2 Index Map.................................................... .................................................... 2a Soil Conditions................................................................................................. 4 Liquefaction and Dynamic Settlement................................................... ........... 4 Seismic Shear-Wave Survey........................................................... ..... 6 Conclusions.......................................................................................... 6 Recommendations.............................................................................. 7 Shallow Foundation Design .. ...... ...... ... .. ... ................................. 7 Foundation Design for Piers ..... .. .. .. ... .. .... .. ..... .. .. .. .. .. .. .. .. .... .. .. .. .. .. .. .. .. 7 Seismic Design Parameters................................................................ 7 Lateral Loading ............. ...................................................................... 8 Slabs-On-Grade . .. ... . . . .. ... .. .. . . . . . . .. . . . . .. . . . . . . .. . . . .. .. . . . . .. . .. . . . .. . .. . . .. . . . . .. .. . . . . . 9 Site Preparation.. .................................................. .............................. 10 Shrinkage and Subsidence................................................................. 13 Asphalt Concrete and Portland Cement Concrete Pavement.............. 14 Chemical Test Results.. .... ..................... ........... ... ..... ... .... ..... ... 15 Foundation and Grading Plan Review . .. .. .. .. .. . .. .. . . .. . ............. .. .. .. .. . . 16 Construction Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 GEOTECHNICAL ENGINEERS• TESTING AND INSPECTION
2257 South Lilac Ave., Bloomington, CA 92316-2903
Bloomington (909) 877-1324 Riverside (909) 783-1 910 Fax (909) 877-5210 John R. Byerly
N C O R P O R A T E D
Enclosures:
(1) Plot Plan
(2) Test Boring Logs
(3) Maximum Density Determinations
(4) Consolidation Test Results
(5) Direct Shear Test Results
(6) Atterberg Limits Results
(7) Specifications for Aggregate Base
(8) Liquefaction and Dynamic Settlement Analysis
(9) Geologic Hazards Report
GEOTECHNICAL ENGINEERS• TESTING AND INSPECTION
2257 South Lilac Ave., Bloomington, CA 92316-2903
Bloomington (909) 877-1324 Riverside (909) 783-1910 Fax (909) 877-5210
INTRODUCTION
During January and February of 2023, an investigation of the soil conditions underlying the proposed park building, garden storage building, and bridge site at the existing Norm Ross Sports Complex was conducted by this firm. The purpose of our investigation was to evaluate the surface and subsurface conditions at the site with respect to safe and economical foundation types, vertical and lateral bearing values, liquefaction and seismic settlement potential, support of concrete slabs-ongrade, and site preparation. Included in the recommendations are the seismic design parameters as required by the 2022 California Building Code and the ASCE Standard 7-16. Recommendations are also provided for design of asphalt concrete and portland cement concrete pavement for the proposed fire lane access road, and for design of portland cement concrete pavement for areas to receive only pedestrian traffic. A geologic hazards report was prepared in our behalf by our consulting engineering geologist, Terra Geosciences, for submission to the California Geologic Survey for review. The geologic hazards report is presented herewith as Enclosure 9. A shear-wave survey of the subsurface material was performed by our consulting geophysicist, Terra Geosciences.
The shear-wave survey is presented as "Appendix A" in the geologic hazards report by Terra Geosciences. A site-specific ground motion analysis was conducted to determine the seismic design parameters as required by the 2022 edition of the California Building Code and ASCE Standard 7-
16. The site-specific ground motion analysis is presented as "Appendix B" in the geologic hazards report by Terra Geosciences. Our geotechnical investigation, together with our conclusions and recommendations, is discussed in detail in the following report.
This report has been prepared for the exclusive use of PBK Architects and their design consultants for specific application to the project described herein. Should the project be modified, the conclusions and recommendations presented in this report should be reviewed by the geotechnical engineer. Our professional services have been performed, our findings obtained, and our recommendations prepared in accordance with generally accepted engineering principles and practices. This warranty is in lieu of all other warranties, express or implied. 1 Rpt. No.: 7650-a
File No.: S-14556
PROJECT DESCRIPTION
For the preparation of this report, we reviewed the project floor plan and site plan provided by PBK Architects. We understand that planned improvements to the existing Norm Ross Sports Complex will consist of a new park building and garden storage building that will have footprint areas of about 2,650 square feet and 142 square feet, respectively. The proposed buildings will be single-story structures of wood-frame construction, and will incorporate concrete slab-on-grade floors. The buildings will impose relatively light foundation loads on the underlying soils. We also understand that a bridge is proposed, which will extend from the existing Stanton Park to the Norm Ross Sports Complex, and will span across the Orange County's flood control channel. This bridge will serve as the main sports complex access for pedestrians, and for service and emergency vehicles. Lastly, we understand that a fire lane access road will be constructed. The site for the proposed park building appears to be at the approximate desired grade, and no significant additional cuts and fills seem likely. The site configuration is illustrated on Enclosure 1.
SITE CONDITIONS
The existing Norm Ross Sports Complex is located at the south terminus of Cedar Street and west of Beach Boulevard in the city of Stanton. An Index Map showing the general vicinity of the site is presented on the following page. The coordinates of the site are latitude 33.8004° N and longitude -117 .9952° W (World Geodetic System of 1984 ). The sports complex is currently occupied by the Stanton Community Garden, and a softball field area. The areas to be developed for the new park building and garden storage building are presently occupied by the Stanton Community Garden, and are also grass- and dirt-covered. The Stanton Storm Channel is adjacent to the sports complex's northern property boundary. The channel is concrete lined, trapezoidal in cross section, and about 10 feet in depth. Commercial development is located to the east of the site. Carver Elementary School is situated to the west, and single-family residences occupy the properties to the south. The area topography is generally flat, and the site slopes downward to the southwest at an average gradient of less than 1 percent.
FIELD AND LABORATORY INVESTIGATION
The underlying soils in the immediate vicinity of the new park building, garden storage building, and bridge sites were explored by three test borings drilled with a limited-access track-mounted 2 Rpt. No.: 7650-a
File No.: S-14556
I l ~ .u :u nction 2 "' e
DAVMOR AVE
t;
:l LESSUE AVE ...
~ ------11
>!-----11---,-- ~ ..... ...,...--~-'t---'---
INDEX MAP
HARLE AVE
W PACIFIC AVE
.t
GARDEN G OVE BLVD
SOURCE DOCUMENTS: USGS ANAHEIM QUADRANGLE, CALIFORNIA, 7.5 MINUTE SERIES, 2018 TOWNSHIP AND RANGE: SECTION 26, T4S, R11W
LATITUDE: 33.8004° N
LONGITUDE: -117.9952° W
2a
John R. Byerly
I N C O R P O R A T E D
Rpt. No.: 7650-a
File No.: S-14556
flight-auger to depths of up to 76 feet below the existing ground surface. The approximate locations of the test borings are indicated on Enclosure 1. The soils encountered were examined and visually classified by one of our field engineers. A summary of the soil classifications appears as Enclosure 2. The exploration logs show subsurface conditions at the dates and locations indicated, and may not be representative of other locations and times. The stratification lines presented on the logs represent the approximate boundaries between soil types, and the transitions may be gradual. A hollow-stem auger with an outside diameter of 7.9 inches was utilized. The inside diameter of the auger was 4.3 inches.
Bulk and relatively undisturbed samples were obtained at selected levels within the explorations and delivered to our laboratory for testing and evaluation. The driving energy or blow counts required to advance the sampler at each sample interval were also noted. Relatively undisturbed soil samples were recovered at various intervals in the borings with a California sampler. The California sampler was a 2.9-inch outside diameter, 2.5-inch inside diameter, split-barrel sampler lined with brass tubes.
The sampler was 18 inches long. The sampler conformed to the requirements of ASTM D 3550. A 140-pound automatic trip hammer was lifted hydraulically and was dropped 30 inches for each blow.
Standard penetration tests were performed as Boring 1 was advanced. The standard penetration test blow counts are shown on the log for Boring 1. Standard penetration testing was performed with a 2.0-inch outside diameter, 1.5-inch inside diameter, split-barrel sampler. The sampler was 18 inches long and was unlined. The sampler conformed to the requirements of ASTM D1586. A 140- pound automatic trip hammer was lifted hydraulically and was dropped 30 inches for each blow. An efficiency value of 1.0 was assumed for the automatic trip hammer.
Included in our laboratory testing were moisture/density determinations on all undisturbed samples. Optimum moisture content/maximum dry density relationships were established for typical soil types so that the relative compaction of the subsoils could be determined.
Consolidation testing was conducted on selected samples to evaluate the compressibility characteristics of the soil. Direct shear testing was conducted on a selected sample to determine its strength parameters. Atterberg limits testing was conducted on selected samples to measure the plasticity of the soil. The moisture/density data are presented on the boring logs presented in Enclosure 2. The maximum density and consolidation test results appear on Enclosures 3 and 4, respectively. The results of direct shear and Atterberg limits testing appear on Enclosures 5 and 6, respectively. Chemical testing, comprised of pH, soluble sulfate, chloride, redox potential, 3 Rpt. No.: 7650-a
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and resistivity testing, was also performed. These test results are presented in the "Chemical Test Results" section of this report.
SOIL CONDITIONS
The upper soils encountered in our test borings consisted of loose to medium dense silty sands, silty sands with traces of gravel, silty sands with traces of clay, and sands; and soft sandy silts with clay.
The loose and soft soils extended to depths ranging from about 5.0 feet to 8.0 feet. The deeper soils consisted of medium dense to very dense silty sands and sands; and medium stiff to very stiff sandy silts with clay and clayey silts with sand. Consolidation tests indicate a potential for 2.5 to 3.2 percent hydroconsolidation in the upper soil. Free ground water was encountered in Borings 1, 2, and 3 at depths of 18.8 feet, 19.9 feet, and 24. 7 feet, respectively. Bedrock was not noted at our boring locations. The near-surface soils observed in our test borings are granular and non-plastic, and are considered to have a very low expansion potential in accordance with ASTM D4829.
LIQUEFACTION AND DYNAMIC SETTLEMENT
Liquefaction is a phenomenon that occurs when a soil undergoes a transformation from a solid state to a liquefied condition due to the effects of increased pore-water pressure. Loose saturated soils with particle sizes in the medium sand to silt range are particularly susceptible to liquefaction when subjected to seismic ground shaking. Affected soils lose all strength during liquefaction, and foundation failure can occur.
Free ground water was encountered in Borings 1, 2, and 3 at depths of 18.8 feet, 19.9 feet, and
24.7 feet, respectively. Based on ground water data, our consulting engineering geologist estimates that the shallowest historic depth to ground water is expected to have been deeper than 8 feet below existing grade. For the purpose of our liquefaction analysis, we have conservatively assumed an historic high ground water level at a depth of 8 feet.
It is anticipated that major earthquake ground shaking will occur during the lifetime of the proposed development from the seismically active Newport-Inglewood fault located approximately 6.5 miles southwest of the site. This fault would create the most significant earthshaking event. Based on an earthquake magnitude of 7.2, a peak horizontal ground acceleration of 0.65g is assigned to the site. To evaluate the potential for liquefaction and seismically induced settlement of the 4 Rpt. No.: 7650-a
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subsoils, the soils were analyzed for relative density. The most effective measurement of relative density of sands with respect to liquefaction potential is standard penetration resistance.
Standard penetration tests were performed as Boring 1 was advanced to a depth of 76 feet. The standard penetration test "N" values are presented on the logs for Boring 1.
Using the information presented in Table 3 of Page 73 of the publication by Idriss and Boulanger (Soil Liquefaction During Earthquakes, Idriss and Boulanger, MNO-12, 2008) an analysis was conducted to determine the sampler correction factor Cs. The SPT sampler is machined to fit liners, therefore a correction factor of 1.0 may not be appropriate. Throughout the test boring, a calculation was performed to determine the average (N1 )50 value from which Cs was subsequently determined. An average Cs value of 1.2 was calculated and used in the analysis.
The standard penetration data provided input for the LiquefyPro Version 4.3 program for liquefaction and seismically induced settlement. As indicated in Special Publication 117 A (Revised) Release, "Guidelines for Evaluating and Mitigating Seismic Hazards in California, March 2009," a safety factor of 1.3 was used in this analysis. We have assumed that the upper 7 feet of soil will be overexcavated and replaced as engineered fill, and that the bottom of overexcavation would be scarified to a depth of 12 inches. The engineered fill was assumed to have an "N" value of 30. The results of this evaluation are shown on Enclosure 8. This analysis reveals a total potential dynamic settlement of
1.50 inches in Boring 1. The total settlement will occur over a large area and will not affect local buried utilities. Within the building area, we would estimate the differential dynamic settlement would be about one-half the total. Based on a minimum park building dimension of about 60 feet, a maximum angular distortion of about 1/960 is calculated, which is within tolerable limits. In addition, the result of the Atterberg testing indicate the silts will behave as clay under seismic conditions. It is our judgment that neither liquefaction nor seismically induced dry settlement need be a consideration in the design of the presently proposed park building or bridge. 5 Rpt. No.: 7650-a
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SEISMIC SHEAR-WAVE SURVEY
One 161-foot-long seismic line was performed near the proposed construction area. The results of the seismic shear-wave survey conducted by Terra Geosciences revealed that the average shearwave velocity ("weighted average") in the upper 100 feet of the subject survey area is 675. 7 feet per second. The report states that: ""This average velocity classifies the underlying soils to that of Site Class "D" (Stiff Soil profile), which has a velocity range from 600 to 1,200 feet/second (ASCE, 2017; Table 20.3-1)."" The report also states that: "''The "weighted average" velocity is computed from a formula that is used by the ASCE (2017; Section 20.4, Equation 20.4-1) to determine the average shear-wave velocity for the upper 100 feet of the subsurface (V100)."" Lastly, the report states that:
"The detailed shear-wave model displays these calculated layer boundaries/depths and associated velocities (feet/second) for the 144-foot profile where locally measured." The shear-wave survey is presented as "Appendix A" in the geologic hazards report by Terra Geosciences, Enclosure 9.
CONCLUSIONS
The upper soils encountered in our explorations are loose and soft to depths ranging from about
5.0 feet to 8.0 feet below the presently existing ground surface. These loose soil layers encountered in our test borings are subject to significant hydroconsolidation. To assure uniform and acceptable foundation conditions, we recommend that the loose and soft upper soils within the new structure areas and new footing excavations be densified by subexcavation and recompaction where existing improvements will allow. Complete stabilization of the existing soil under pavement areas would require removal and recompaction of the existing loose soil. The cost of complete removal and recompaction of the existing loose soil within pavement areas does not appear to be warranted. Substantial stabilization can be obtained by removal and recompaction of the upper 3 feet of soil within pavement areas. Recommendations for foundation design and slabs-on-grade are provided below for a very low expansion potential (Expansion Index of O to 20). Subsequent to site preparation, the new structures may be safely founded on conventional continuous and isolated footings bearing entirely on compacted fill. The bridge will likely be supported by drilled cast-in-place piers. Detailed recommendations are provided below. 6 Rpt. No.: 7650-a
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RECOMMENDATIONS
SHALLOW FOUNDATION DESIGN
Where the site is prepared as recommended, the new park building and garden storage building may be founded on conventional shallow footings. The footings should be at least 12 inches wide and should be placed at least 12 inches below the lowest final adjacent grade. These footings should be designed for a maximum safe soil bearing pressure of 2,000 pounds per square foot for dead plus live loads. Increasing the footing embedment depth to 18 inches would allow the utilization of a maximum soil bearing pressure of 2,500 pounds per square foot. These values may be increased by one-third for wind and seismic loading.
Continuous footings should be reinforced with at least two No. 4 bars, one placed near the top and one near the bottom of the footings. This recommendation for foundation reinforcement is based on geotechnical considerations. Structural design may require additional foundation reinforcement.
FOUNDATION DESIGN FOR PIERS
We anticipate that the bridge will likely be supported by pier-type foundations. For piers with embedment depths of 10 feet to 16 feet, an allowable average skin friction of 200 pounds per square foot to 295 pounds per square foot may be assumed. Intermediate values may be determined by interpolation. These values may be increased by one-third for wind or seismic loading. Lateral load capacity of the pier footings may be computed using any accepted pole footing formula assuming an allowable lateral earth pressure of 350 pounds per square foot per foot of depth to a maximum of 3,000 pounds per square foot.
SEISMIC DESIGN PARAMETERS
The development of the seismic ground motion parameters is described in detail in the geologic hazards report performed in our behalf by Terra Geosciences (Enclosure 9). In summary, the 2022 California Building Code and the ASCE Standard 7-16 coefficients and factors are provided in the following table:
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Factor or Coefficient Value
Latitude 33.8004° N
Longitude -117.9952° w
Ss 1.423g
S1 0.503g
Fa 1.0
Fv 1.797
Sos 0.990g
S 0 1 1.050g
SMs 1.484g
SMt 1.573g
T L 8 seconds
PGA 0.65g
Site Class D
LATERAL LOADING
For level backfill surface and cantilever retaining wall conditions, we recommend an active fluid pressure of 35 pounds per square foot per foot of depth, exclusive of surcharge loads. For braced walls with level backfill surface conditions, we recommend an at-rest fluid pressure of 60 pounds per square foot per foot of depth, exclusive of surcharge loads. For shallow footings, resistance to lateral loads will be provided by passive earth pressure and basal friction. For footings bearing against compacted fill, passive earth pressure may be considered to develop at a rate of 300 pounds per square foot per foot of depth. Basal friction may be computed at 0.35 times the normal dead load.
The resistance from basal friction and passive earth pressure may be combined directly without reduction. Retaining walls should be provided with a backdrain system or weep holes to prevent buildup of hydrostatic pressure behind the walls. Retaining wall backfill should exhibit very low expansion potential, and should be densified to a relative compaction of at least 90 percent (ASTM D1 557).
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SLABS-ON-GRADE
Concrete slab-on-grade design recommendations are listed below. The slab-on-grade recommendations assume underlying utility trench backfills and pad subgrade soils have been densified to a relative compaction of at least 90 percent (ASTM D1557).
1. It is our opinion that the recommended compacted fill soils should provide adequate support for concrete slabs-on-grade without the use of a gravel base. The final pad surface should be rolled to provide a smooth dense surface upon which to place the concrete.
2. Slab-on-grade floors should be at least 4 inches thick- structural considerations may require a thicker slab. The concrete slabs-on-grade may be designed using a modulus of subgrade reaction of 250 pounds per cubic inch.
3. It is recommended that concrete slabs-on-grade be reinforced with No. 3 bars at 16 inches on-center each way in the middle third of the slab. All slab reinforcement should be supported by chairs or precast concrete blocks to ensure positioning of reinforcement in the slab. Lifting of unsupported reinforcement during concrete placement should not be allowed.
4. Slabs to receive moisture-sensitive floor coverings should be underlain with a moisture vapor retardant membrane, such as 15-mil Stego Wrap or equivalent. The moisture vapor retardant membrane should conform to ASTM E 17 45-11 (Standard Specification for Plastic Water Vapor Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs). The moisture vapor retardant membrane should be lapped into the footing excavations to provide full coverage of the subgrade soils. Punctures and/or holes cut for plumbing should be taped to minimize moisture emissions through the membrane. The project superintendent or a representative of the geotechnical engineer should inspect the placement of the moisture vapor retardant membrane prior to covering. Installation of the moisture vapor retardant membrane should be performed in accordance with ASTM E 1643-11 (Standard Practice for Selection, Design, Installation and Inspection of Water Vapor Retarders Used in Contact with Earth or Granular Fill under Concrete Slabs).
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5. A 2-inch layer of clean sand (SE>30, no more than 7 percent passing the No. 200 sieve) should be placed over the moisture vapor retardant membrane to promote uniform setting of the concrete. Concrete should be placed on the sand blanket when the sand is damp.
Excess moisture should not be allowed to accumulate within the sand blanket prior to concrete placement. At the time of concrete placement, the moisture content of the sand blanket above the moisture vapor retardant membrane should not exceed 2 percent below the optimum moisture content.
6. In lieu of placing the sand blanket described above and to further minimize future moisture vapor emissions through the slabs-on-grade, the slab concrete may be placed directly on the moisture vapor retardant membrane. Placing concrete directly on the moisture vapor retardant membrane will increase shrinkage and curling forces and make finishing more difficult. To accommodate these concerns, the structural engineer should provide appropriate mix design criteria for concrete placed directly on the moisture vapor retardant membrane.
7. We recommend a maximum water-cement ratio of 0.50 for all building slab concrete.
Architectural or structural considerations may require the utilization of a lower watercement ratio. Where slab concrete is placed directly on the moisture vapor retardant membrane without the presence of an intervening layer of absorptive sand, a lower maximum water-cement ratio may be needed.
8. Preparation of the concrete floor slabs should conform to ASTM F 710-11 (Standard Practice for Preparing Concrete Floors to Receive Resilient Flooring) and the manufacturer's recommendations. Moisture vapor emission tests should be performed to verify acceptable moisture emission rates prior to flooring installation.
SITE PREPARATION
We assume that the site will be prepared in accordance with the California Building Code and the current City of Stanton Grading Ordinance. The recommendations presented below are to establish additional grading criteria. These recommendations should be considered preliminary and are subject to modification or expansion based on a geotechnical review of the project foundation and grading plans.
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• All areas to be graded should be stripped of organic matter, man-made obstructions, and other deleterious materials. Underground utilities should be removed and/or relocated. All cavities created during site clearing should be cleaned of loose and disturbed soil, shaped to provide access for construction equipment, and backfilled with fill placed and compacted as described below.
• Soil disturbed during demolition of the existing structures and utilities should be overexcavated below all areas to receive improvements, including structure, pavement, and hardscape areas.
• Any existing artificial fill should be removed from the proposed improvement areas, including structure, pavement, and hardscape areas. The removals should extend beyond the structure areas a horizontal distance at least equal to the depth of removal or 5 feet, whichever distance is greater. Organic matter and other unsuitable debris should be separated from the removed fill and hauled from the site. The removed artificial fill should be stockpiled pending replacement or be placed in areas previously prepared. • Overexcavation
o New park building and garden storage building areas - Subsequent to removal of any undocumented fill, the upper soil underlying the new structure areas, including roof overhang footings, should be overexcavated to a depth of at least 7 feet below the presently existing ground surface or final ground surface. The soil exposed in subexcavated surfaces should be evaluated by a representative of the geotechnical engineer. The overexcavation should extend beyond the structure area a horizontal distance at least equal to the depth of overexcavation below the bottom of the footings or 5 feet, whichever is greater. The slope of the backcut should be at a gradient no steeper than 1 H: 1 V. The representative of the geotechnical engineer should evaluate the conditions encountered and determine where the overexcavation can be terminated.
o In order to not damage the existing Orange County's flood control channel walls, slot cutting should be performed within 10 feet of the existing flood control channel walls. Slot cutting should be performed in alternate segments with a maximum 11 Rpt. No.: 7650-a
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width of 10 feet as measured parallel to the existing flood control channel walls.
The recommended limits of overexcavation and recompaction should be followed for the initial segments. Subsequent to completion of the initial segments, the intermediate 10-foot segments should be prepared. The use of a sheepsfoot roller on the end of a backhoe boom would be acceptable within 6 feet of the existing flood control channel walls.
o In lieu of replacing the overexcavated soil with engineered fill, the void created from the slot cut overexcavation may be backfilled with a sand slurry containing at least 2 sacks of cement per cubic yard. Each slot should be backfilled with slurry the same day it is excavated. No slot should be allowed to stand open overnight.
The adjacent slots should be excavated no sooner than 4 hours following the placement of the slurry in the preceding slot. The excavation of the loose and soft upper natural soils, and the placement of the engineered fill soils or slurry backfill should be monitored by the representative of the geotechnical engineer. o Pavement and hardscape areas - Loose soil underlying pavement and hardscape areas should be removed to a minimum depth of 3 feet. Should competent natural soil be encountered at a depth of less than 3 feet below asphalt concrete and portland cement concrete pavement areas, the overexcavation can be terminated at that depth. The soils exposed in the subexcavated surface should be scarified to a depth of at least 12 inches. The scarified soil should be moisture conditioned to near the optimum moisture content, and densified to a relative compaction of at least 90 percent (ASTM D1557).
• Subexcavated surfaces and all other surfaces to receive fill should be scarified to a minimum depth of 12 inches, moisture conditioned to near the optimum moisture content, and densified to a minimum relative compaction of 90 percent (ASTM D1557). • The on-site soils should provide adequate quality fill material provided they are free from significant organic matter and other deleterious materials, and are at acceptable moisture contents. Any asphalt and portland cement concrete removed during site clearing may be pulverized into fragments not exceeding 3 inches in greatest dimension and incorporated into the fill at all levels in the building area. Import fill should be inorganic, granular, non12 Rpt. No.: 7650-a
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expansive soil free from rocks or lumps greater than 8 inches in maximum dimension, and should exhibit a very low expansion potential ( expansion index less than 21 ), negligible sulfate content (less than 1,000 ppm soluble sulfate by dry weight of soil), and low corrosion potential. Prior to bringing import fill to the site, the contractor should obtain certification to verify that the proposed import meets the State of California Department of Toxic Substance Control (DTSC) environmental standards. Proposed import should be sampled at the source and tested by this firm for expansion index, soluble sulfate content, and corrosion potential.
• All fill should be placed in 8-inch or less lifts. Each lift of fill should be moisture conditioned to near the optimum moisture content, and densified to a minimum relative compaction of 90 percent (ASTM D1557). Where the horizontal limits of overexcavation cannot be achieved, the engineered fill should be densified to a relative compaction of at least 95 percent.
• The surface of the site should be graded to provide positive drainage away from the structure. Drainage should be directed to established swales and then to appropriate drainage structures to minimize the possibility of erosion. Water should not be allowed to pond adjacent to footings.
SHRINKAGE AND SUBSIDENCE
Volume change in going from cut to fill conditions is anticipated where near-surface grading will occur. Assuming the fill will be compacted to an average relative compaction of 93 percent, an average cut-fill shrinkage of 1 Oto 15 percent is estimated. Further volume loss will occur through subsidence during preparation of the natural ground surface. Although the contractor's methods and equipment utilized in preparing the natural ground will have a significant effect on the amount of natural ground subsidence that will occur, our experience indicates as much as 0.1 O to 0.15 foot of subsidence in areas prepared to receive fill should be anticipated. These values are exclusive of losses due to stripping or removal of subsurface obstructions. 13 Rpt. No.: 7650-a
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ASPHALT CONCRETE AND PORTLAND CEMENT CONCRETE PAVEMENT
Our Boring 2 was drilled in the vicinity of the proposed fire lane access road and encountered silty sand in the upper soils. We estimate this soil will exhibit an "R" value of at least 40. We assume that the fire lane access road pavement will need to support an 80,000-pound fire truck visiting the site on average twice a year. Based on these parameters, we recommend the pavement section for the new fire lane access road consist of 3.0 inches of asphalt concrete over 6.5 inches of aggregate base. We also recommend portland cement concrete (PCC) pavement for the new fire lane access road should be at least 6.0 inches in thickness. This thickness is for unreinforced concrete placed directly on the compacted subgrade soil. Aggregate base is not geotechnically required for the PCC pavement sections; however, if aggregate base is to be utilized for the PCC pavement, we recommend a minimum of 4 inches of aggregate base placed over the 12 inches of compacted subgrade soil. The design engineer may wish to provide some level of reinforcement to minimize the width of shrinkage cracks.
For hardscape areas to receive only pedestrian traffic, we recommend the PCC pavement be at least 3.5 inches in thickness and be placed directly on the compacted subgrade soil. Prior to the placement of hardscape concrete, we recommend that the final subgrade surface be scarified to a depth of at least 12 inches, moisture conditioned to near the optimum moisture content, and densified to a minimum relative compaction of 90 percent (ASTM 01557). There are no geotechnical conditions indicating the need for reinforcement of the concrete pavement. The design engineer may wish to provide some level of reinforcement to minimize the width of shrinkage cracks.
Concrete should be proportioned for a maximum slump of 4 inches and to achieve a minimum compressive strength of 3,000 psi at 28 days. If additional workability is desired, a plasticizing or water-reducing admixture should be utilized in lieu of increasing the water content. Control joints for the 3.5-inch-thick pavement should be spaced no more than 10.5 feet on-center each way. The control joints for the 6.0-inch-thick pavement should be spaced no more than 18.0 feet on-center each way. Control joints should be established either by hand groovers, plastic inserts, or sawcutting as soon as the concrete can be cut without dislodging aggregate. Cutting the control joints the day after the concrete pour will likely result in uncontrolled shrinkage cracks. Concrete should not be placed in hot and windy weather. Water curing should commence immediately after the final finishing and should continue for at least 7 days.
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The above designs are preliminary and for estimating purposes only. We recommend that during the process of rough grading, observation and additional testing of the actual subgrade soils should be performed. Final pavement design sections can then be determined. The foregoing pavement sections assume that utility trench backfill below all proposed pavement areas will be compacted to at least 90 percent relative compaction. Prior to the placement of aggregate base, we recommend that the final subgrade surface be scarified to a depth of at least 12 inches, moisture conditioned to near optimum moisture content, and compacted to a relative compaction of at least 90 percent (ASTM D1557). Aggregate base should be densified to at least 95 percent relative compaction. Suggested specifications for aggregate base material are presented on Enclosure 7.
The preparation of the subgrade and compaction of the aggregate base should be monitored by a representative of the geotechnical engineer.
CHEMICAL TEST RESULTS
The chemical test results from a sample taken from Boring 1 between the ground surface and a depth of 5 feet are shown on the following table:
Analysis Result Units
Saturated Resistivity 2500 ohm-cm
Chloride 50 ppm
Sulfate 50 ppm
pH 7.7 pH units
Redox Potential 125 mV
The chemical test results from a sample taken from Boring 3 between the ground surface and a depth of 5 feet are shown on the following table:
Analysis Result
Saturated Resistivity 4600
Chloride ND (Not Detected)
Sulfate 10
pH 7.8
Redox Potential 210
15 Units
ohm-cm
ppm
ppm
pH units
mV
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The soil tested in Borings 1 and 3 exhibited negligible soluble sulfate content; therefore, sulfateresistant concrete will not be required for this project. In addition, the results of the corrosivity testing indicate that the soils tested are not detrimentally corrosive to ferrous-metal pipes.
FOUNDATION AND GRADING PLAN REVIEW
The project foundation and grading plans should be reviewed by the geotechnical engineer.
Additional recommendations may be required at that time.
CONSTRUCTION OBSERVATIONS
All grading operations, including the preparation of the natural ground surface, should be observed and compaction tests performed by this firm. No fill should be placed on any prepared surface until that surface has been evaluated by the representative of the geotechnical engineer.
The footing excavations for the new structure should be evaluated by a representative of the geotechnical engineer.prior to placement of reinforcing steel or forms. A representative of the geotechnical engineer should be present during the excavation of the pier-type footings to verify correlation of the soil conditions encountered with those anticipated, to verify embedment depths.
The conclusions and recommendations presented in this report are based upon the field and laboratory investigation described herein and represent our best engineering judgment. Should conditions be encountered in the field that appear different from those described in this report, we should be contacted immediately in order that appropriate recommendations might be prepared. 16 Rpt. No.: 7650-a
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Respectfully submitted,
JOHN R. BYERLY, INC.
John R. Byerly, Geotechnical Engineer
President
JRB:MLL:st
Enclosures: (1) Plot Plan
(2) Test Boring Logs
(3) Maximum Density Determinations
(4) Consolidation Test Results
(5) Direct Shear Test Results
(6) Atterberg Limits Results
(7) Specifications for Aggregate Base
(8) Liquefaction and Dynamic Settlement Analysis
(9) Geologic Hazards Report
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B-3 B-1 B-2 LEGEND APPROX. BORING LOCATION NORM ROSS SPORTS COMPLEX 11111 CEDAR STREET STANTON, CALIFORNIA GEOTECHNICAL INVESTIGATION SOURCE DOCUMENT: GOOGLE EARTH Enclosure 1 Rpt. No.: 7650-a File No.: S-14556 0 80' 160' N SCALE: 1" = 80
GEOLOGIC HAZARDS REPORT
PROPOSED PARK BUILDING AND STORM CHANNEL BRIDGE
NORM ROSS SPORTS COMPLEX
11111 CEDAR STREET, STANTON, CALIFORNIA
Project No. 233932-1
April 11, 2023
Prepared for:
John R. Byerly, Inc.
2257 South Lilac Avenue
Bloomington, CA 92316
Consulting Engineering Geology & Geophysics ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- P.O. Box 1090, Loma Linda, CA 92354 • 909 796-4667
Enclosure 9, Page 1
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John R. Byerly, Inc.
2257 South Lilac Avenue
Bloomington, CA 92316
Attention: Mr. John R. Byerly
Regarding: Geologic Hazards Report
Proposed Park Building and Storm Channel Bridge
Norm Ross Sports Complex
11111 Cedar Street, Stanton, California
JRB File No. S-14556
At your request, this firm has prepared a geologic hazards report for the proposed park building and storm channel bridge, within the existing Norm Ross Sports Complex, as referenced above. The purpose of this study was to evaluate the existing geologic conditions of the property and any corresponding potential geologic and/or seismic hazards, with respect to the proposed development from a geologic standpoint. This report has been prepared utilizing the suggested “Checklist for the Review of Engineering Geology and Seismology Reports for California Public Schools, Hospitals, and Essential Services Buildings” (CGS Note 48, 2022), along with the Geologic portion of the “Factors to Be Included in the Geological and Environmental Hazards Report,” which is included as Appendix H of the “School Site Selection and Approval Guide,” prepared by the School Facility Planning Division, California Department of Education (2021), and the Geohazard Reports requirements outlined by the DSA (2021). The scope of services provided for this evaluation included the following:
Review of available published and unpublished geologic/seismic data in our files pertinent to the site, including the provided site-specific boring logs. Performing a seismic surface-wave survey by a licensed State of California Professional Geophysicist that included one traverse for shear-wave velocity analysis purposes. Evaluation of the local and regional tectonic setting and historical seismic activity, including performing a site-specific CBC ground motion analysis. Preparation of this report presenting our findings, conclusions, and recommendations from a geologic standpoint.
Accompanying Maps, Illustrations, and Appendices
Plate 1 - Regional Geologic Map
Plate 2 - Seismic Hazards Zone Map
Plate 3 - Google™ Earth Imagery Map
Plate 4 - Park Plan
Appendix A - Shear-Wave Survey
Appendix B - Site-Specific Ground Motion Analysis
Appendix C - References
Enclosure 9, Page 2
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PROJECT SUMMARY
We understand that this report will be appended to your current geotechnical investigation, therefore, some descriptive sections such as site description, proposed development, etc., have been purposely omitted as they have been described in detail in your referenced report. No grading plans were available for this evaluation, and no field or subsurface exploration was performed by this firm. Only a review of available geologic and geotechnical data in our files was undertaken, including the geotechnical Investigation of the subject site performed by John R. Byerly, Inc. (JRB, 2023), including performing a seismic shear-wave survey.
GEOLOGIC SETTING
The subject property is located in southwestern California, within a natural geomorphic province known as the Peninsular Ranges. The Peninsular Ranges is generally characterized by steep, elongated ranges and valleys that trend northwesterly. The northern end of this province includes the Los Angeles Basin, which is a northwesttrending alluvial lowland plain about 50 miles long and 20 miles wide. The Los Angeles Basin is, in turn, comprised of several structural blocks or subdivisions which are separated by major zones of faulting or flexures in the basement rock.
More specifically, the site is located within the Central Block of the Los Angeles Basin, which is wedge-shaped and approximately 55 miles long from northwest to southeast, ranging from 10 to 20 miles wide. This block is generally bounded by the Santa Monica Mountains to the north, the Whittier Fault Zone to the northeast, the Newport-Inglewood Fault Zone to the southwest, and the San Joaquin Hills to the southeast. This block contains a maximum thickness of 32,000 feet of marine and non-marine clastic sedimentary rocks of late Cretaceous through Pleistocene age.
Locally, as mapped by Morton (2006), the site is shown to be underlain by Quaternary age (Holocene to late Pleistocene) young alluvial fan deposits comprised mostly of unconsolidated to moderately consolidated silt, sand, pebbly cobbly sand, and bouldery alluvial-fan deposits having slightly to moderately dissected surfaces, as shown on Plate 1 (map symbol Qyf). Additionally, mapping by the California Geological Survey (2010) also indicates the site to be underlain by Holocene to late Pleistocene age earth materials generally characterized as unconsolidated- to slightly-consolidated boulder, cobble, gravel, sand, and silt deposits having undissected to slightly dissected surfaces.
Site-specific subsurface exploration performed by JRB (2023), indicates the proposed construction area in the upper 8± feet to be mantled by soft sandy silts with clay, loose to medium dense silty sands with variable amounts of clay, sand, and gravel.
Underlying these surficial sediments are medium dense to very dense silty sands and sands, and medium stiff to very stiff sandy silts with clay and clayey silts with sand, to a depth of at least 76 feet.
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FAULTING
There are at least forty-one major late Quaternary active/potentially active faults that are located within a 100-kilometer (62 mile) radius of the subject school site (Blake, 1989- 2000a). Of these, there are no known active faults that traverse the site based on available published literature, nor was there any surficial geomorphic that was suggestive of faulting. The subject site is not located within a State of California "Alquist-Priolo Earthquake Fault Zone" for fault rupture hazard (California Geological Survey, 2018).
The nearest mapped (zoned) “active” fault is for the Newport-Inglewood Fault (Onshore), which is shown to be located approximately 6½ miles to the southwest (C.D.M.G., 1986). The Newport-Inglewood Fault (mapped on-shore segment) is approximately 65.5± kilometers in length and has an estimated rupture area of 980.5± square kilometers. This fault is characterized by right-lateral, strike-slip movement, with an associated slip-rate of 1 ±0.5 mm/year, and a characteristic return interval of 1,006 years, with an estimated Maximum Moment Magnitude Earthquake of MW7.2. The "maximum moment” (MW) earthquake is the maximum earthquake that is specific to that source based on estimated rupture dimensions for that segment of the design fault.
Values for the “maximum moment magnitude” earthquake and associated fault data as outlined above have been compiled from data provided by the C.D.M.G. (1996); Cao et al. (2003); and Petersen et al. (2008).
The Newport-Inglewood Fault Zone consists of a series of northwest-trending, rightlateral strike-slip faults and form short, discontinuous, generally left-stepping en-echelon patterns when at or near the surface (Bryant, 1988). Within this zone, there are associated northwest- to west-trending, right-stepping anticlinal folds and numerous short subsidiary normal and reverse faults. This fault zone is seismically active of which the M6.3 1933 Long Beach Earthquake occurred, located 13± miles to the south.
The nearest mapped fault that is not zoned as “active” by the California Geological Survey is the Anaheim Fault (Field et al., 2013), located approximately 0.9± miles to the northeast. This fault is a reverse fault that dips 71 degrees to the northeast, with an estimated Maximum Moment Magnitude Earthquake of MW6.4.
FLOODING
According to the Federal Emergency Management Agency (FEMA, 2009), the subject property is not shown to be located within the boundaries of a designated 100-year flood (Community Panel Number 06059C0136J, December 3, 2009). This map indicates that the site is located within "Zone X" which is defined as “Areas of 0.2% Annual Chance Flood.” According to the City of Stanton’s Flood Map (2008, Exhibit 6- 3), the subject site is also shown to be located within “Areas of 0.2% Annual Chance Flood.”
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GROUND MOTION ANALYSIS
According to California Geological Survey Note 48 (CGS, 2022), a site-specific ground motion analysis is required for the subject site (CBC, 2022, Section 1613A and as also required by ASCE 7-16, Chapter 21), the detailed results of which are presented within Appendix B. Additionally, a seismic shear-wave survey was conducted for this study by our firm as presented within Appendix A of this report for purposes of determining the soil Site Classification and VS30 input values for the ground motion analysis.
Geographically, the subject construction area is centrally located at Latitude 33.8004 and Longitude -117.9952 and (World Geodetic System of 1984 coordinates). The mapped spectral acceleration parameters, coefficients, and other related seismic parameters, were evaluated using the OSHPD Seismic Design Maps (OSHPD, 2023) and the California Building Code criteria (CBC, 2022), with the site-specific ground motion analysis being performed following Section 21 of the ASCE 7-16 Standard (2017). The results of this site-specific analysis have been summarized and are tabulated below:
TABLE 1 – SUMMARY OF SEISMIC DESIGN PARAMETERS
Factor or Coefficient Value
SS 1.423g
S1 0.503g
Fa 1.0
Fv 1.797
SDS 0.990g
SD1 1.050g
SMS 1.484g
SM1 1.573g
TL 8 Seconds
MCEG PGA 0.65g
Shear-Wave Velocity (V100) 675.7 ft/sec
Site Classification D
Risk Category III
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HISTORIC SEISMICITY
A computerized search, based on Southern California historical earthquake catalogs, has been performed using the computer program EQSEARCH (Blake, 1989-2000b) and the ANSS Comprehensive Earthquake Catalog (U.S.G.S., 2023a). The following table and discussion summarizes the historic seismic events (greater than or equal to M4.0) that have been estimated and/or recorded during the time period of 1800 to April 2023, within a 100-kilometer radius of the site.
TABLE 1 - HISTORIC SEISMIC EVENTS; 1800-2023 (100-kilometer radius) Richter Magnitude (M) No. of Events
4.0 - 4.9 467
5.0 - 5.9 56
6.0 - 6.9 15
7.0 - 7.9 1
8.0+ 0
It should be noted that pre-instrumental seismic events (generally before 1932) have been estimated from isoseismal maps (Toppozada, et al., 1981 and 1982). These data have been compiled generally based on the reported intensities throughout the region, thus focusing in on the most likely epicentral location. Instrumentation beyond 1932 has greatly increased the accuracy of locating earthquake epicenters. A summary of the historic earthquake data is as follows:
The nearest estimated significant historic earthquake epicenter (pre-1932) was approximately 14 miles to the northwest (December 25, 1903, M5.0). The nearest recorded significant historic earthquake epicenter was a magnitude 5.0 event, located 2± miles to the south (M5.0), which occurred on March 11, 1933. The largest estimated historical earthquake magnitude was a M7.0 event of September 24, 1827 (approximately 59 miles west-northwest). The largest recorded historical earthquake was the M6.7 Northridge event, located approximately 42 miles to the northwest (January 17, 1994). The largest estimated ground acceleration to have been experienced at the site was
0.183g which resulted from the M6.3 Long Beach earthquake of March 14, 1933, which was located approximately 13 miles to the south (Blake, 1989-2000b).
An Earthquake Epicenter Map which includes magnitudes 4.0 and greater for a 100- kilometer radius from the site (central blue dot), is shown below as Figure 1. This map was prepared using the ANSS Comprehensive Earthquake Catalog (U.S.G.S., 2023) of instrumentally recorded events from the period of 1932 to April 2023.
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FIGURE 1- Earthquake Epicenter Map showing events of M4.0+ within a 100-kilometer radius.
GROUNDWATER
The subject site is located within the Coastal Plain of Orange County Basin (Orange County Basin), which underlies the coastal alluvial plain in the northwestern portion of Orange County. The basin is bounded by the Puente and Chino Hills to the north, the east by the Santa Ana Mountains, the south by in the San Joaquin Hills, the Pacific Ocean on the southwest, and by a low topographic divide approximated by the Orange County - Los Angeles County line on the northwest. This basin is a deep structural depression which contains a thick accumulation of fresh water-bearing interbedded marine and continental sand, silt, and clay deposits. Recharge to the basin is derived from percolation, infiltration of precipitation, and injection into wells.
Using the U.S.G.S. water well database (U.S.G.S., 2023c), the nearest known measured water well is located approximately 1,500± feet to the northwest (State Well No. 04S11W26B001S). This well indicates that groundwater levels have ranged from 26± to 44± feet in depth between the years 1969 to 1997. Seismic hazard mapping prepared by the California Division of Mines and Geology (2018), shows the site to be located with a zone of potential liquefaction, which generally indicates present or historic groundwater levels of 50-feet or less, as presented on the Seismic Hazards Map, Plate
2. Subsurface exploration performed by JRB (2023), encountered groundwater as shallow as 19± feet in depth. High groundwater contour data prepared by the California Geological Survey (1997) indicates that historic groundwater levels have been as high as 8± feet in depth.
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SECONDARY SEISMIC HAZARDS
Secondary permanent or transient seismic hazards that are generally associated with severe ground shaking during an earthquake include ground rupture, liquefaction, seiches or tsunamis, flooding (water storage facility failure), ground lurching/lateral spreading, landsliding, rockfalls, and seismically-induced settlement. These hazards are discussed below.
Ground Rupture- Ground rupture is generally considered most likely to occur along pre-existing faults. Since no known active faults are believed to traverse the subject site, the probability of ground rupture is considered very low.
Ground Lurching/Lateral Spreading- Ground lurching is the horizontal movement of soil, sediments, or fill located on relatively steep embankments or scarps as a result of seismic activity, forming irregular ground surface cracks. The potential for lateral spreading or lurching is highest in areas underlain by soft, saturated materials, especially where bordered by steep banks or adjacent hard ground. Due to the flatlying nature of the site, distance from embankments, the potential for ground lurching and/or lateral spreading is nil.
Flooding (Water Storage Facility Failure)- Based on the City of Stanton “Prado Dam Potential Inundation Areas” map (2008, Exhibit 6-4), the subject site is shown to be located within the “Limits of the Flood Due to Dam Failure”, associated with Prado Dam”, which is located approximately 21¼± miles to the east-northeast. Additionally, the United States Army Corp of Engineers (2023) also indicates the site to be located within a flood inundation zone from failure of Prado Dam, along with potential inundation occurring from failure of the Carbon Canyon Dam, located approximately 11¾± miles to the northeast. Therefore, the potential for flooding due to water storage facility failure is considered possible.
Seiches/Tsunamis- Based on the far distance of large, open bodies of water and the elevation of the site with respect to sea level, the possibility of seiches/tsunamis is considered nil. Additionally, mapping by the California Geological Survey (2014) does not indicate the site to be located within a tsunami inundation zone.
Liquefaction- In general, liquefaction is a phenomenon that occurs where there is a loss of strength or stiffness in the soils from repeated disturbances of saturated cohesionless soil that can result in the settlement of buildings, ground failures, or other such related hazards. The main factors generally contributing to this phenomenon are:
1) cohesionless, granular soils having relatively low densities (usually of Holocene age); 2) shallow groundwater (generally less than 40 feet); and 3) moderate-high seismic ground shaking. The California Geological Survey (2018) indicates the subject property to be located within a mapped zone for liquefaction potentials (1998 Seismic Hazards Enclosure 9, Page 8
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Zone Map), as shown on Plate 2. In addition, the City of Stanton (2008) also indicates the site to be located within a potential liquefaction zone (Potential Liquefaction Areas; Exhibit 6-2). Based on this zoning, the shallow groundwater encountered during site exploration (JRB, 2023), high regional seismic potentials, and the unconsolidated nature of the alluvial sediments, there appears to be a moderate to high potential for liquefaction to occur.
Landsliding- Due to the relatively low-lying relief of the site, landsliding due to seismic shaking is considered nil. The California Geological Survey (2018) does not indicate the subject school site to be located within a mapped zone for landslide potentials (1998 Seismic Hazards Zone Map, see Plate 2).
Rockfalls- The site lies upon a relatively flat-lying alluvial plain. Since no large rock outcrops are present at or adjacent to the site, the possibility of rockfalls during seismic shaking is nil.
Seismically-Induced Settlement- Seismically-induced settlement generally occurs within areas of loose granular soils. The proposed construction area is locally mantled in the upper 8± feet by interbedded, soft sandy silts with clay, loose to medium dense silty sands with variable amounts of clay, sand, and gravel. Underlying these surficial sediments are medium dense to very dense silty sands and sands, and medium stiff to very stiff sandy silts with clay and clayey silts with sand, to a depth of at least 76 feet.
Therefore, there may be a potential for seismically-induced settlement to occur, especially in the upper near-surface sediments.
OTHER GEOLOGIC HAZARDS
There are other potential geologic hazards not necessarily associated with seismic activity that occur statewide. These hazards include; natural hazardous materials (such as methane gas, hydrogen-sulfide gas, and tar seeps); Radon-222 gas (EPA, 1993); naturally occurring asbestos; volcanic hazards (Martin, 1982); and regional subsidence.
Of these hazards, there are none that appear to impact the site.
CONCLUSIONS AND RECOMMENDATIONS
General:
Based on our review of available pertinent published and unpublished geologic/seismic literature, construction of the proposed park building and storm channel bridge, within the existing Norm Ross Sports Complex, appears to be feasible from a geologic standpoint, providing our recommendations are considered during planning and construction.
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Conclusions:
1. Based on available published geologic data and review of the provided boring logs, the site is underlain by Quaternary age (Holocene to late Pleistocene) young alluvial fan deposits comprised mostly of unconsolidated- to slightly-consolidated boulder, cobble, gravel, sand, and silt deposits having undissected to slightly dissected surfaces. Site-specific exploration by JRB indicates the proposed construction site to be mantled within the upper 8± feet by soft sandy silts with clay, loose to medium dense silty sands with variable amounts of clay, sand, and gravel. Underlying these surficial sediments are medium dense to very dense silty sands and sands, and medium stiff to very stiff sandy silts with clay and clayey silts with sand, to a depth of at least 76 feet.
2. Groundwater was encountered within the exploratory excavations performed by JRB as shallow as 19± feet. Based on available published data, historic groundwater levels have ranged from 26± to 44± feet in depth from a well located approximately 1,500± feet to the northwest. High groundwater contour data prepared by the California Geological Survey indicates that historic groundwater levels have been as high as 8± feet in depth.
3. Based on our literature research, there are no active faults that are known to traverse the subject construction area. The nearest zoned active fault is associated with the active Newport-Inglewood Fault located approximately 6½± miles to the southwest that has an estimated maximum moment magnitude of MW 7.2. The nearest fault that is not zoned as “active” by the California Geological Survey is the Anaheim Fault located approximately 0.9± miles to the southwest, with an estimated Maximum Moment Magnitude Earthquake of MW6.4.
4. The primary geologic hazard that exists at the site is that of ground shaking, which accounts for nearly all earthquake losses. Moderate to severe ground shaking could be anticipated during the life of the proposed development.
5. Based on our review of available geologic and geotechnical literature and reports, there may be a potential for liquefaction, secondary seismic settlement, and flood inundation from dam failure to occur. No other permanent and/or transient secondary seismic hazards are expected to occur within the proposed construction area.
Recommendations:
1. The potential for flooding due to catastrophic failure of Prado and Carbon Canyon Dams should be properly evaluated by the project Civil Engineer. Appropriate sitespecific mitigation measures, should be implemented as recommended, if warranted.
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2. The potential for liquefaction and seismically-induced settlement should be properly evaluated by the project Geotechnical Engineer. A high groundwater level of 8-feet should be used for analysis purposes. Appropriate site-specific mitigation measures, should be implemented as recommended, if warranted.
3. It is recommended that all structures be designed to at least meet the current California Building Code provisions in the latest 2022 CBC edition and the 2016 ASCE Standard 7-16, where applicable. However, it should be noted that the building code is intended as a minimum construction design and is often the maximum level to which structures are designed. Structures that are built to minimum code are designed to at least remain operational after an earthquake. It is the responsibility of both the property owner and project structural engineer to determine the risk factors with respect to using CBC minimum design values for the proposed facilities.
CLOSURE
Our conclusions and recommendations are based on a review of available existing geologic/seismic data and the provided site-specific provided subsurface exploratory boring logs. No subsurface exploration was performed by this firm for this evaluation.
The results of the seismic parameter values were based on the U.S. Seismic “Design Maps” OSHPD Web Application (California’s Office of Statewide Health Planning and Development); as provided by the U.S.G.S. and as requested by the CGS for inclusion in this report. We make no warranty, either express or implied.
Should conditions be encountered at a later date or more information becomes available that appear to be different than those indicated in this report, we reserve the right to reevaluate our conclusions and recommendations and provide appropriate mitigation measures, if warranted. It is assumed that all the conclusions and recommendations outlined in this report are understood and followed. If any portion of this report is not understood, it is the responsibility of the owner, contractor, engineer, and/or governmental agency, etc., to contact this office for further clarification.
Respectfully submitted,
TERRA GEOSCIENCES
Donn C. Schwartzkopf
Principal Geologist / Geophysicist
CEG 1459 / PGP 1002
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REGIONAL GEOLOGIC MAP
BASE MAP: Morton and Miller (2006), U.S.G.S. OFR 2006-1217, Scale 1: 100,000, Site outlined in red.
PARTIAL LEGEND
YOUNG FAN DEPOSITS Unconsolidated to moderately-consolidated silt, sand, pebbly cobbly sand, and bouldery
alluvial-fan deposits (Holocene and late
Pleistocene).
GEOLOGIC CONTACT Solid where well-located to approximatelylocated, dashed where inferred.
FAULT Solid where accurately located, dashed
where approximate, dotted where concealed.
PROJECT NO. 233932-1 PLATE 1
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SEISMIC HAZARDS MAP
BASE MAP: CGS (2018), Earthquake/Seismic Hazards Zones, Scale 1: 24,000, Site outlined in red.
PROJECT NO. 233932-1 PLATE 2
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GOOGLE™ EARTH IMAGERY MAP
Base Map: Google™ Earth (2023); Seismic shear-wave traverse SW-1 shown as blue line.
PROJECT NO. 233932-1 PLATE 3
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PARK PLAN
Base Map: Provided Park Plan; Seismic shear-wave traverse SW-1 shown as blue line; Proposed construction shown in red.
PROJECT NO. 233932-1 PLATE 4
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APPENDIX A
SHEAR-WAVE SURVEY
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SHEAR-WAVE SURVEY
Methodology
The fundamental premise of this survey uses the fact that the Earth is always in motion at various seismic frequencies. These relatively constant vibrations of the Earth’s surface are called microtremors, which are very small with respect to amplitude and are generally referred to as background “noise” that contain abundant surface waves.
These microtremors are caused by both human activity (i.e., cultural noise, traffic, factories, etc.) and natural phenomenon (i.e., wind, wave motion, rain, atmospheric pressure, etc.) which have now become regarded as useful signal information.
Although these signals are generally very weak, the recording, amplification, and processing of these surface waves has greatly improved by the use of technologically improved seismic recording instrumentation and recently developed computer software.
For this application, we are mainly concerned with the Rayleigh wave portion of the seismic signals, which is also referred to as “ground roll” since the Rayleigh wave is the dominant component of ground roll.
For the purposes of this study, there are two ways that the surface waves were recorded, one being “active” and the other being “passive.” Active means that seismic energy is intentionally generated at a specific location relative to the survey spread and recording begins when the source energy is imparted into the ground (i.e., MASW survey technique). Passive surveying, also called “microtremor surveying,” is where the seismograph records ambient background vibrations (i.e., MAM survey technique), with the ideal vibration sources being at a constant level. Longer wavelength surface waves (longer-period and lower-frequency) travel deeper and thus contain more information about deeper velocity structure and are generally obtained with passive survey information. Shorter wavelength (shorter-period and higher-frequency) surface waves travel shallower and thus contain more information about shallower velocity structure and are generally collected with the use of active sources.
For the most part, higher frequency active source surface waves will resolve the shallower velocity structure and lower frequency passive source surface waves will better resolve the deeper velocity structure. Therefore, the combination of both of these surveying techniques provides a more accurate depiction of the subsurface velocity structure.
The assemblage of the data that is gathered from these surface wave surveys results in development of a dispersion curve. Dispersion, or the change in phase velocity of the seismic waves with frequency, is the fundamental property utilized in the analysis of surface wave methods. The fundamental assumption of these survey methods is that the signal wavefront is planar, stable, and isotropic (coming from all directions) making it independent of source locations and for analytical purposes uses the spatial autocorrelation method (SPAC). The SPAC method is based on theories that are able to detect “signals” from background “noise” (Okada, 2003). The shear wave velocity (Vs) can then be calculated by mathematical inversion of the dispersive phase velocity of the surface waves which can be significant in the presence of velocity layering, which is common in the near-surface environment.
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Field Procedures
One shear-wave survey traverse (SW-1) was performed along an accessible area proximal to the proposed construction, as approximated on the Google™ Earth Imagery Map and the Park Plan (see Plates 3 and 4, respectively). For data collection, the field survey employed a twenty-four channel Geometrics StrataVisorTM NZXP model signalenhancement refraction seismograph. This survey employed both active source (MASW) and passive (MAM) methods to ensure that both quality shallow and deeper shear-wave velocity information was recorded (Park et al., 2005).
Both the MASW and MAM survey lines used the same linear geometry array that consisted of a 161-foot-long spread using a series of twenty-four 4.5-Hz geophones that were spaced at regular seven-foot intervals. For the active source MASW survey, the ground vibrations were recorded using a one second record length at a sampling rate of
0.5-milliseconds. Two separate seismic records were obtained using a 25-foot shot offset at both ends of the line utilizing a 16-pound sledge-hammer as the energy source to produce the seismic waves. Numerous seismic impacts were used at each shot location to improve the signal-to-noise ratio.
The MAM survey did not require the introduction of any artificial seismic sources with only background ambient noise (i.e., air and vehicle traffic, etc.) being necessary.
These ambient ground vibrations were recorded using a thirty-two second record length at a two-millisecond sampling rate with twenty separate seismic records being obtained for quality control purposes. The frequency spectrum data that was displayed on the seismograph screen were used to assess the recorded seismic wave data for quality control purposes in the field. The acceptable records were digitally recorded on the inboard seismograph computer and subsequently transferred to a flash drive so that they could be subsequently transferred to our office computer for analysis.
Data Reduction
For analysis and presentation of the shear-wave profile and supportive illustration, this study used the SeisImager/SWTM computer software program that was developed by Geometrics, Inc. (2009). Both the active (MASW) and passive (MAM) survey results were combined for this analysis (Park et al., 2005). The combined results maximize the resolution and overall depth range in order to obtain one high resolution Vs curve over the entire sampled depth range. These methods economically and efficiently estimate one-dimensional subsurface shear-wave velocities using data collected from standard primary-wave (P-wave) refraction surveys.
However, it should be noted that surface waves by their physical nature cannot resolve relatively abrupt or small-scale velocity anomalies and this model should be considered as an approximation. Processing of the data then proceeded by calculating the dispersion curve from the input data from both the active and passive data records, which were subsequently combined creating an initial shear-wave (Vs) model based on the observed data. This initial model was then inverted in order to converge on the best fit of the initial model and the observed data, creating the final Vs curve as presented within this appendix.
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Summary of Data Analysis
Data acquisition went very smoothly and the quality was considered to be good.
Analysis revealed that the average shear-wave velocity (“weighted average”) in the upper 100 feet of the subject survey area is 675.7 feet per second as shown on the shear-wave model for Seismic Line SW-1, as presented within this appendix. This average velocity classifies the underlying soils to that of Site Class “D” (Stiff Soil profile), which has a velocity range from 600 to 1,200 ft/sec (ASCE, 2017; Table 20.3-1).
The “weighted average” velocity is computed from a formula that is used by the ASCE (2017; Section 20.4, Equation 20.4-1) to determine the average shear-wave velocity for the upper 100 feet of the subsurface (V100).
Vs = 100/[(d1/v1) + (d2/v2) + ...+ (dn/vn)]
Where d1, d2, d3,...,tn, are the thicknesses for layers 1, 2, 3,...n, up to 100 feet, and v1, v2, v3,...,vn, are the seismic velocities (feet/second) for layers 1, 2, 3,...n. The detailed shear-wave model displays these calculated layer boundaries/depths and associated velocities (feet/second) for the 144-foot profile where locally measured. The constrained data is represented by the dark-gray shading on the shear-wave model.
The associated Dispersion Curves (for both the active and passive methods) which show the data quality and picks, along with the resultant combined dispersion curve model, are also included within this appendix, for reference purposes.
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SURVEY LINE PHOTOGRAPHS
View looking northeast along Seismic Line SW-1.
View looking southwest along Seismic Line SW-1.
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0 10
20 30
40 50
60 70
80 90
100
110
120
130
140
150
Depth (ft)
0 250 500 750 1000 1250
S-wave velocity (ft/s)
S-wave velocity model (inverted): Final.rst Average Vs 100ft = 675.7 ft/sec 497
7.2 531
16.1 604
26.6 657
38.7 710
52.4 724
67.7 775
84.6 817
103.1
865
123.3
896
SEISMIC LINE SW-1
SHEAR-WAVE MODEL
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2000
1750
1500
1250
1000
750
500
250
0 Phase velocity (ft/s)
0 5 10 15 20 25 30 35 40
Frequency (Hz)
Dispersion curve : Combined.rst
SEISMIC LINE SW-1
COMBINED DISPERSION CURVE
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SEISMIC LINE SW-1
ACTIVE DISPERSION CURVE
Dispersion Cure: Active.dat
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SEISMIC LINE SW-1
PASSIVE DISPERSION CURVE
Dispersion Curve: Passive.dat
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APPENDIX B
SITE-SPECIFIC GROUND MOTION ANALYSIS
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SITE-SPECIFIC GROUND MOTION ANALYSIS
A detailed summary of the site-specific ground motion analysis, which follows Section 21 of the ASCE Standard 7-16 and the 2022 California Building Code is presented below, with the Seismic Design Parameters Summary included within this appendix following the summary text.
♦ Mapped Spectral Acceleration Parameters (CBC 1613A.2.1)- Based on maps prepared by the U.S.G.S (Risk-Adjusted Maximum Considered Earthquake (MCER) Ground Motion Parameter for the Conterminous United States for the 0.2 and 1-second Spectral Response Acceleration (5% of Critical Damping; Site Class B/C), a value of 1.423g for the 0.2 second period (Ss) and 0.503g for the
1.0 second period (S1) was calculated (ASCE 7-16 Figures 22-1, 22-2 and CBC 1613A.2.1).
♦ Site Classification (CBC 1613A.2.2 & ASCE 7-16 Chapter 20)- Based on the site-specific measured shear-wave value of 675.7 feet/second (206.0 m/sec), the soil profile type used should be Site Class “D.” This Class is defined as having the upper 100 feet (30 meters) of the subsurface being underlain by stiff soil with average shear-wave velocities of 600 to 1,200 feet/second (180 to 360 meters/second), as detailed within Appendix A.
♦ Site Coefficients (CBC 1613A.2.3)-
Based on CBC Tables 1613A.2.3(1) and 1613A.2.3(2), the site coefficient Fa = 1.0 and Fv = 1.797, respectively.
♦ Probabilistic (MCER) Ground Motions (ASCE 7 Section 21.2.1)- Per Section 21.2.1, the probabilistic MCE spectral accelerations shall be taken as the spectral response accelerations in the direction of maximum response represented by a five percent damped acceleration response spectrum that is expected to achieve a one percent probability of collapse within a 50-year period.
The probabilistic analysis included the use of the Open Seismic Hazard Analysis (OpenSHA). The selected Earthquake Rupture Forecast (ERF) was UCERF3 along with a Probability of Exceedance of 2% in 50 Years. The average of four Next Generation Attenuation West-2 Relations (2014 NGA) were utilized to produce a response spectrum. These included Chiou & Youngs (2014), Abrahamsom et al. (2014), Campbell & Bozorgnia (2014), Boore et al. (2014), and Campbell & Bozorgnia (2014). The Probabilistic Risk Targeted Response Spectrum was determined as the product of the ordinates of the probabilistic response spectrum and the applicable risk coefficient (CR). These values were then modified to produce a spectrum based upon the maximum rotated components of ground motion. The resulting MCER Response Spectrum is indicated below:
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♦ Deterministic Spectral Response Analyses (ASCE 7 Section 21.2.2)- The deterministic MCER response acceleration at each period shall be calculated as an 84th-percentile 5 percent damped spectral response acceleration in the direction of maximum horizontal response computed at that period. The largest such acceleration calculated for the characteristic earthquakes on all known active faults within the region shall be used. Analyses were conducted using the average of four Next Generation Attenuation West-2 Relations (2014 NGA), including Chiou & Youngs (2014), Abrahamsom et al. (2014), Boore et al. (2014) and Campbell & Bozorgnia (2014).
The design faults that were used in this analysis are based on our review of the Fault Section Database within the Uniform California Earthquake Rupture Forecast (UCERF 3; Field et al., 2013) and discussions with the California Geologic Survey (CGS), and are based on the length and maximum magnitude of each of the nearby Anaheim, Elysian Park, Puente Hills (Coyote Hills Segment), Compton Thrust, and Newport-Inglewood (which includes the five individual fault segments) faults.
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♦ Site Specific MCER (ASCE 7 Section 21.2.3)-
The site-specific MCER spectral response acceleration at any period, SaM, shall be taken as the lesser of the spectral response accelerations from the probabilistic ground motions of Section 21.2.1 and the deterministic ground motions of Section
21.2.2. The deterministic ground motions were compared with the probabilistic ground motions that were determined in accordance with Section 21.2.1.
Comparison of Deterministic MCER Values with Probabilistic MCER Values - Section 21.2.3 Period Deterministic Probabilistic
Governing Method
T MCER MCER
Lower Value (Site
Specific MCER)
0.010 0.91 0.67 0.67 Probabilistic Governs
0.020 0.90 0.68 0.68 Probabilistic Governs
0.030 0.88 0.69 0.69 Probabilistic Governs
0.050 0.92 0.77 0.77 Probabilistic Governs
0.075 1.06 0.98 0.98 Probabilistic Governs
0.100 1.22 1.29 1.22 Deterministic Governs
0.150 1.41 1.38 1.38 Probabilistic Governs
0.200 1.60 1.50 1.50 Probabilistic Governs
0.250 1.80 1.59 1.59 Probabilistic Governs
0.300 2.05 1.65 1.65 Probabilistic Governs
0.400 2.38 1.64 1.64 Probabilistic Governs
0.500 2.54 1.58 1.58 Probabilistic Governs
0.750 2.55 1.36 1.36 Probabilistic Governs
1.000 2.52 1.22 1.22 Probabilistic Governs
1.500 2.17 0.93 0.93 Probabilistic Governs
2.000 1.83 0.76 0.76 Probabilistic Governs
3.000 1.13 0.52 0.52 Probabilistic Governs
4.000 0.74 0.38 0.38 Probabilistic Governs
5.000 0.52 0.29 0.29 Probabilistic Governs
7.500 0.25 0.16 0.16 Probabilistic Governs
10.000 0.13 0.09 0.09 Probabilistic Governs
These are plotted in the following diagram:
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♦ Design Response Spectrum (ASCE 7 Section 21.3)-
In accordance with Section 21.3, the Design Response Spectrum was developed by the following equation: Sa = 2/3SaM, where SaM is the MCER spectral response acceleration obtained from Section 21.1 or 21.2. The design spectral response acceleration shall not be taken less than 80 percent of Sa. These are plotted and compared with 80% of the CBC Spectrum values in the following diagram:
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♦ Design Acceleration Parameters (ASCE 7 Section 21.4)- Where the site-specific procedure is used to determine the design ground motion in accordance with Section 21.3, the parameter SDS shall obtained from the sitespecific spectra at a period of 0.2 s, except that it shall not be taken less than 90 percent of the peak spectral acceleration, Sa, at any period larger than 0.2 s. The parameter SD1 shall be taken as the greater of the products of Sa * T for periods between 1 and 5 seconds. The parameters SMS, and SM1 shall be taken as 1.5 times SDS and SD1, respectively. The values so obtained shall not be less than 80 percent of the values determined in accordance with Section 11.4.4 for SMS, and SM1 and Section 11.4.5 for SDS and SD1.
♦ Site Specific Design Parameters -
For the 0.2 second period (SDS), a value of 0.990g was computed, based upon the average spectral accelerations. The maximum average acceleration for any period exceeding 0.2 seconds was 1.10g occurring at T=0.30 seconds. This was multiplied by 0.9 to produce a value of 0.990g making this the applicable value. A value of
1.050g was calculated for SD1 at a period of 1 second (ASCE 7-16, 21.4). For the MCER 0.2 second period, a value of 1.484g (SMS) was computed, along with a value of 1.573g (SM1) for the MCER 1.0 second period was also calculated (ASCE 7-16,
21.2.3).
♦ Site-Specific MCEG Peak Ground Accelerations (ASCE 7 Section 21.5)- The probabilistic geometric mean peak ground acceleration (2 percent probability of exceedance within a 50-year period) was calculated as 0.65g. The deterministic geometric mean peak ground acceleration (largest 84th percentile geometric mean peak ground acceleration for characteristic earthquakes on all known active faults within the site region) was calculated as 0.82g. The site-specific MCEG peak ground acceleration was calculated to be 0.65g, which was determined by using the lesser of the probabilistic (0.65g) or the deterministic (0.82g) geometric mean peak ground accelerations, but not taken as less than 80 percent of PGAM (i.e., 0.67g x 0.80 =
0.54g).
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SEISMIC DESIGN PARAMETERS SUMMARY
Project: Norm Ross Sports Complex Lattitude: 33.8004
Project #: 233932-1 Longitude: -117.9952
Date: 3/30/2023
CALIFORNIA BUILDING CODE CHAPTER 16/ASCE7-16
Mapped Acceleration Parameters per ASCE 7-16, Chapter 22 Ss= 1.423 Figure 22-1
S1= 0.503 Figure 22-2
Site Class per Table 20.3-1
Site Class= D - Stiff Soil
Site Coefficients per ASCE 7-16 CHAPTER 11
Fa= 1 Table 11.4-1 = 1 For Site Specific Analysis per ASCE7-16 21.3 Fv= 1.797 Table 11.4-2 = 2.50 For Site Specific Analysis per ASCE7-16 21.3 Mapped Design Spectral Response Acceleration Parameters SMs= 1.423 Equation 11.4-1 1.423 For Site Specific Analysis per ASCE7-16 21.3 SM1= 0.904 Equation 11.4-2 1.258 For Site Specific Analysis per ASCE7-16 21.3 T0= 0.127 sec
TS= 0.635 sec
SDS= 0.949 Equation 11.4-3 TL= 8 sec From Fig 22-12
SD1= 0.603 Equation 11.4-4 PGA 0.608 g
FPGA= 1.1 From Table 11.8-1
CRS= 0.915 Figure 22-17
Period (T)
Sa
(ASCE7-16 -
11.4.6)
80% General
Design
Spectrum CR1= 0.918 Figure 22-18
0.01 0.38 0.30
0.13 0.95 0.76
0.20 0.95 0.76
0.64 0.95 0.76
0.70 0.86 0.69
0.80 0.75 0.60
0.90 0.67 0.54
1.00 0.60 0.48
1.10 0.55 0.44
1.20 0.50 0.40
1.30 0.46 0.37
1.40 0.43 0.34
1.50 0.40 0.32
1.60 0.38 0.30
1.70 0.35 0.28
1.80 0.33 0.27
1.90 0.32 0.25
2.00 0.30 0.24
3.00 0.20 0.16
4.00 0.15 0.12
5.00 0.12 0.10
7.50 0.08 0.06
10.00 0.05 0.04
0.00 0.10
0.20 0.30
0.40 0.50
0.60 0.70
0.80 0.90
1.00 0.00 2.00 4.00 6.00 8.00 10.00 12.00
General Design Spectrum 80% General Design Spectrum
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ASCE 7-16 - RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE GROUND MOTION ANALYSIS Use Maximum Rotated Horizontal Component?* (Y/N) Y
Presented data are the average of Chiou & Youngs (2014), Abrahamson et. al. (2014) , Boore et. al (2014) and Campbell & Bozorgnia (2014) NGA West-2 Relationships Earthquake Rupture Forecast - UCERF3 FM 3.2
PROBABILISTIC MCER per 21.2.1.1 Method 1
Risk Coefficients taken from Figures 22-18 and 22-19 of ASCE 7-16 OpenSHA data
2% Probability Of Exceedance in 50 years
Maximum Rotated Horizontal Component determined per ASCE7-16 T
Sa
2% in 50 MCER
0.01 0.73 0.67
0.02 0.74 0.68
0.03 0.75 0.69
0.05 0.85 0.77
0.08 1.07 0.98
0.10 1.28 1.29
0.15 1.51 1.38
0.20 1.64 1.50
0.25 1.73 1.59
0.30 1.80 1.65
0.40 1.79 1.64
0.50 1.72 1.58
0.75 1.48 1.36
1.00 1.33 1.22
1.50 1.01 0.93
2.00 0.83 0.76
3.00 0.57 0.52
4.00 0.41 0.38
5.00 0.32 0.29
7.50 0.17 0.16
10.00 0.10 0.09
Ss= 1.64 1.50
S1= 1.33 1.22
PGA 0.65 g
Risk Coefficients:
CRS 0.915 Figure 22-18 Get from Mapped Values
CR1 0.918 Figure 22-19
Fa= 1 Table 11.4-1 Per ASCE7-16 - 21.2.3
Is Sa(max)<1.2XFa? NO If "YES", Probabilistic Spectrum prevails
0.00 0.20
0.40 0.60
0.80 1.00
1.20 1.40
1.60 1.80
0 2 4 6 8 10 12
Spectral Acceleration (g)
Period (sec)
PROBABILISTIC GROUND MOTIONS
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DETERMINISTIC MCE per 21.2.2
Preliminary Assessment:
Fault Distance (km)
14.20 10.50
8.60 7.30
69.00 1.40
Puente Hills (Coyote Hills)
The Probalistic Analyses revealed 6 faults contributing more than 10% to the seismic hazard. These were considered in the Deterministic Analyses which was controlled by the Comption Fault throughout the range of the spectrum.
San Andreas
Anaheim
Compton
Newport-Inglewood
Elysian Park
0.0 0.5
1.0 1.5
2.0 2.5
0 1 2 3 4 5 6 7 8 9 10 11
Spectral Acceration Sa (g)
Period T (sec).
DETERMINISTIC ANALYSES COMPARISONS
Compton
NewportInglewood
San Andreas
Anaheim
Elysian Park
Puente Hills
(Coyote Hills)
CONTROLING FAULT:
Compton
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Input Parameters
Fault
M = Moment magnitude 7.5 7.2 7 6.4
R RUP = Closest distance to coseismic rupture (km) 9.7 10.5 8.6 1.4 R JB = Closest distance to surface projection of coseismic rupture (km) 0 10.5 8.6 1.4 Rx = Horizontal distance to top edge of rupture measured perpendicular to strike (km) 14.2 10.5 8.6 1.4 U = Unspecified Faulting Flag (Boore et.al.) 0 0 0 0
F RV 1 0 1 1
F NM 0 0 0 0
FHW 1 0 0 0
Z TOR = Depth to top of coseismic rupture (km) 5.2 0 2.1 3.8 δ = Average dip of rupture plane (degrees) 20 90 26 90
VS30 = Average shear-wave velocity in top 30m of site profile 206 206 206 206 F Measured 1 1 1 1
Z 1.0 = Depth to Shear Wave Velocity of 1.0 km/sec (km) 0.75 0.75 0.75 0.75 Z 2.5 = Depth to Shear Wave Velocity of 2.5 km/sec (km) 4.75 4.75 4.75 4.75 Site Class D D D D
W (km) = Fault rupture width (km) 30.4 15.1 26.9 11
F AS = 0 for mainshock; 1 for aftershock 0 0 0 0
σ =Standard Deviation 1 1 1 1
Deterministic Summary - Section 21.2.2 (Supplement 1)
T Compton
NewportInglewoodPuente Hills
(Coyote Hills) Anaheim
Maximum Sa
(Average)
Corrected*
Sa
(per ASCE7-16)
Scaled
Sa(Average)
0.010 0.83 0.52 0.55 0.75 0.83 0.91 0.91
0.020 0.82 0.51 0.55 0.74 0.82 0.90 0.90
0.030 0.80 0.51 0.54 0.73 0.80 0.88 0.88
0.050 0.84 0.54 0.57 0.76 0.84 0.92 0.92
0.075 0.97 0.64 0.69 0.89 0.97 1.06 1.06
0.100 1.11 0.76 0.81 1.02 1.11 1.22 1.22
0.150 1.28 0.94 1.00 1.21 1.28 1.41 1.41
0.200 1.45 1.08 1.13 1.35 1.45 1.60 1.60
0.250 1.62 1.19 1.26 1.54 1.62 1.80 1.80
0.300 1.82 1.29 1.36 1.69 1.82 2.05 2.05
0.400 2.07 1.36 1.45 1.82 2.07 2.38 2.38
0.500 2.16 1.36 1.45 1.83 2.16 2.54 2.54
0.750 2.06 1.20 1.27 1.66 2.06 2.55 2.55
1.000 1.94 1.09 1.15 1.52 1.94 2.52 2.52
1.500 1.64 0.87 0.90 1.15 1.64 2.17 2.17
2.000 1.35 0.71 0.73 0.88 1.35 1.83 1.83
3.000 0.81 0.48 0.47 0.51 0.81 1.13 1.13
4.000 0.51 0.34 0.31 0.30 0.51 0.74 0.74
5.000 0.35 0.24 0.22 0.19 0.35 0.52 0.52
7.500 0.16 0.11 0.10 0.07 0.16 0.25 0.25
10.000 0.09 0.06 0.05 0.04 0.09 0.13 0.13
PGA 0.82 0.51 0.55 0.74 0.82 0.82 g
Max Sa= 2.55
Fa = 1.00 Per ASCE7-16 21.2.2
1.5XFa= 1.5
Scaling
Factor= 1.00
* Correction is the adjustment for Maximum Rotated Value if Applicable = Normal-faulting factor: 0 for strike slip, reverse, reverse-oblique and thrust; 1 for normal and normal-oblique
= Hanging-wall factor: 1 for site on down-dip side of top of rupture; 0 otherwise, used in AS08 and CY08
= Reverse-faulting factor: 0 for strike slip, normal, normal-oblique; 1 for reverse, reverse-oblique and thrust
Compton
Compton
Compton Anaheim
Puente Hills
(Coyote
Hills)
Compton
Compton
Compton
Compton
Compton
NewportInglewood
Controlling Fault
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
Compton
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SITE SPECIFIC MCER - Compare Deterministic MCER Values (Sa) with Probabilistic MCER Values (Sa) per 21.2.3 Presented data are the average of Chiou & Youngs (2014), Abrahamson et. al. (2014) , Boore et. al (2014) and Campbell & Bozorgnia (2014) NGA West-2 Relationships Period Deterministic Probabilistic
T MCER MCER
Lower Value
(Site Specific
MCER)
0.010 0.91 0.67 0.67 ProbabilisticGoverns
0.020 0.90 0.68 0.68 ProbabilisticGoverns
0.030 0.88 0.69 0.69 ProbabilisticGoverns
0.050 0.92 0.77 0.77 ProbabilisticGoverns
0.075 1.06 0.98 0.98 ProbabilisticGoverns
0.100 1.22 1.29 1.22 Deterministic Governs
0.150 1.41 1.38 1.38 ProbabilisticGoverns
0.200 1.60 1.50 1.50 ProbabilisticGoverns
0.250 1.80 1.59 1.59 ProbabilisticGoverns
0.300 2.05 1.65 1.65 ProbabilisticGoverns
0.400 2.38 1.64 1.64 ProbabilisticGoverns
0.500 2.54 1.58 1.58 ProbabilisticGoverns
0.750 2.55 1.36 1.36 ProbabilisticGoverns
1.000 2.52 1.22 1.22 ProbabilisticGoverns
1.500 2.17 0.93 0.93 ProbabilisticGoverns
2.000 1.83 0.76 0.76 ProbabilisticGoverns
3.000 1.13 0.52 0.52 ProbabilisticGoverns
4.000 0.74 0.38 0.38 ProbabilisticGoverns
5.000 0.52 0.29 0.29 ProbabilisticGoverns
7.500 0.25 0.16 0.16 ProbabilisticGoverns
10.000 0.13 0.09 0.09 ProbabilisticGoverns
Governing Method
0.0 0.5
1.0 1.5
2.0 2.5
3.0 0 1 2 3 4 5 6 7 8 9 10
Sa (g)
T (seconds)
DETERMINISTIC/PROBABILISTIC MCER COMPARISONS
Deterministic Probabilistic
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DESIGN RESPONSE SPECTRUM per Section 21.3
DESIGN ACCELERATION PARAMETERS per Section 21.4 (MRSA)
Period 2/3*MCER
80% General
Design
Response
Spectrum
(per ASCE 7-
16 23.3-1)
Design
Response
Spectrum TXSa
0.01 0.45 0.33 0.45 Highest value of Sa for any period exceeding 0.2 sec.= 1.10
0.02 0.45 0.35 0.45 90%of Highest Value = 0.99
0.03 0.46 0.37 0.46 80% 0f Mapped SDS= 0.76
0.05 0.52 0.42 0.52 Maximum TXSa from T=1s-5s = 1.05
0.08 0.66 0.47 0.66 80% of Mapped SD1= 0.48
0.10 0.81 0.53 0.81
0.15 0.92 0.65 0.92
0.20 1.00 0.76 1.00 SDS= 0.99 SMS= 1.484
0.25 1.06 0.76 1.06 SD1= 1.05 SM1= 1.573
0.30 1.10 0.76 1.10 Ts = 1.06
0.40 1.09 0.76 1.09
0.50 1.05 0.76 1.05 PGA Determination:
0.75 0.91 0.76 0.91 Site Coefficient FPGA= 1.1
1.00 0.82 0.67 0.82 0.82 Mapped PGA= 0.61 Figure 22-7
1.50 0.62 0.45 0.62 0.93 PGAM = 0.67 g
2.00 0.51 0.34 0.51 1.01
3.00 0.35 0.22 0.35 1.05 Deterministic PGA = 0.82 g
4.00 0.25 0.17 0.25 1.01 Probabilistic PGA = 0.65 g
5.00 0.19 0.13 0.19 0.97 Lesser of Deterministic/Probabilistic = 0.65 g
7.50 0.10 0.09 0.10 80% of PGAM= 0.54 g
10.00 0.06 0.05 0.06 MCEG PGA= 0.65 g
0 0.2
0.4 0.6
0.8 1
1.2 1.4
1.6 1.8
2 0.00
0.20 0.40
0.60 0.80
1.00 1.20
1.40 1.60
1.80 2.00
0.00 2.00 4.00 6.00 8.00 10.00 12.00
Cs x (R/Ie)
Spectral Acceleration (g)
Period (sec)
GROUND MOTION ANALYSIS SUMMARY
80% of General Design
Response Spectrum
MRSA Design Spectrum
ELF Spectrum
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1 2 3 4 5 6 7 8 9 10 11 12
Period
(sec)
Mapped
MCER
Spectrum
Mapped
Design
Spectrum
Period
(sec)
Risk
Coefficient
CR
Scaled MCER
Deterministic
Spectrum
Probabilistic
MCER
Spectrum
Probabilistic
w/Risk
Coeffcicent
CR
84th Percentile
Deterministic
Spectrum
2/3 Site
Specific
MCER
Spectrum
80% of
General
Design
Spectrum
Site
Specific
MCER
Spectrum
Design
Response
Spectrum
0.01 0.57 0.38 0.01 0.915 0.91 0.67 0.67 0.91 0.45 0.33 0.67 0.45
0.13 1.42 0.95 0.02 0.915 0.90 0.68 0.68 0.90 0.45 0.35 0.68 0.45
0.20 1.42 0.95 0.03 0.915 0.88 0.69 0.69 0.88 0.46 0.37 0.69 0.46
0.64 1.42 0.95 0.05 0.915 0.92 0.77 0.77 0.92 0.52 0.42 0.77 0.52
0.70 1.29 0.86 0.08 0.915 1.06 0.98 0.98 1.06 0.66 0.47 0.98 0.66
0.80 1.13 0.75 0.10 0.915 1.22 1.29 1.29 1.22 0.81 0.53 1.22 0.81
0.90 1.00 0.67 0.15 0.915 1.41 1.38 1.38 1.41 0.92 0.65 1.38 0.92
1.00 0.90 0.60 0.20 0.915 1.60 1.50 1.50 1.60 1.00 0.76 1.50 1.00
1.10 0.82 0.55 0.25 0.915 1.80 1.59 1.59 1.80 1.06 0.76 1.59 1.06
1.20 0.75 0.50 0.30 0.915 2.05 1.65 1.65 2.05 1.10 0.76 1.65 1.10
1.30 0.70 0.46 0.40 0.916 2.38 1.64 1.64 2.38 1.09 0.76 1.64 1.09
1.40 0.65 0.43 0.50 0.916 2.54 1.58 1.58 2.54 1.05 0.76 1.58 1.05
1.50 0.60 0.40 0.75 0.917 2.55 1.36 1.36 2.55 0.91 0.76 1.36 0.91
1.60 0.56 0.38 1.00 0.918 2.52 1.22 1.22 2.52 0.82 0.67 1.22 0.82
1.70 0.53 0.35 1.50 0.918 2.17 0.93 0.93 2.17 0.62 0.45 0.93 0.62
1.80 0.50 0.33 2.00 0.918 1.83 0.76 0.76 1.83 0.51 0.34 0.76 0.51
1.90 0.48 0.32 3.00 0.918 1.13 0.52 0.52 1.13 0.35 0.22 0.52 0.35
2.00 0.45 0.30 4.00 0.918 0.74 0.38 0.38 0.74 0.25 0.17 0.38 0.25
3.00 0.30 0.20 5.00 0.918 0.52 0.29 0.29 0.52 0.19 0.13 0.29 0.19
4.00 0.23 0.15 7.50 0.918 0.25 0.16 0.16 0.25 0.10 0.09 0.16 0.10
5.00 0.18 0.12 10.00 0.918 0.13 0.09 0.09 0.13 0.06 0.05 0.09 0.06
7.50 0.12 0.08
10.00 0.07 0.05
SUMMARY OF SITE SPECIFIC GROUND MOTION HAZARD ANALYSIS DATA Project 233932-1 3/30/2023 Page 6
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APPENDIX C
REFERENCES
Enclosure 9, Page 38
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File No.: S-14556
REFERENCES
American Society of Civil Engineers (ASCE), 2017, Minimum Design Loads and Associated Criteria for Buildings and other Structures, ASCE Standard 7-16, 889pp.
Barrows, A.G., 1974, A Review of the Geology and Earthquake History of the NewportInglewood Structural Zone, Southern California, C.D.M.G. Special Report 114.
Blake, T.F. 1989-2000a, EQFAULT, A computer program for the deterministic prediction of peak horizontal acceleration from digitized California faults, Version 2.03, revised 1993.
Blake, T.F. 1989-2000b, EQSEARCH, A computer program for the estimation of peak horizontal acceleration from Southern California Historical Earthquake Catalog, Version
3.00b.
Boore, D.M., Joyner, W.B., and Fumal, T.E., 1997, Equations for Estimating Horizontal Response Spectra and Peak Acceleration from Western North American Earthquakes:
A Summary of Recent Work, in, Seismological Research Letters, Volume 68, pp. 128- 153.
California Building Standards Commission (CBSC), 2022, 2022 California Building Code, California Code of Regulations, Title 24, Part 2, Volume 2 of 2.
California Department of Education, 2021, School Site Selection and Approval Guide, Appendix H, Factors to be Included in a Geological and Environmental Hazards Report.
California Department of Water Resources (CDWR), 1967, Progress Report on Ground Water Geology of the Coastal Plain of Orange County, 138 pp.
California Division of Mines & Geology (C.D.M.G.), 1986, "Guidelines to Geologic/Seismic Reports," Note No. 42.
California Division of Mines & Geology (C.D.M.G.), 1996, Probabilistic Seismic Hazard Assessment for the State of California, C.D.M.G. Open File Report 96-08.
California Division of Mines & Geology (C.D.M.G.), 1997, Seismic Hazard Report for the Anaheim and Newport Beach 7.5-Minute Quadrangles, Los Angeles and Orange Counties, California, Seismic Hazard Report 03.
California Division of the State Architect (DSA), 2021, Geohazard Reports Requirements: 2019 CBC, Interpretation of Regulations Document IR A-4, 7 pp.
California Geological Survey (C.G.S.), 2008, Guidelines for Evaluating and Mitigating Seismic Hazards, in California C.D.M.G. Special Publication 117.
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California Geological Survey (C.G.S), 2022, Checklist for the Review of Engineering Geology and Seismology Reports for California Public Schools, Hospitals, and Essential Services Buildings, Note 48, November 20, 2 pp.
California Geological Survey (C.G.S.), 2018, Earthquake Fault Zones: A Guide for Government Agencies, Property Owners/Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, CGS Special Publication 42, 93 pp.
California’s Office of Statewide Health Planning and Development (OSHPD), 2023, OSHPD Seismic Design Maps Tool web application, https://seismicmaps.org/.
California State Board for Geologists and Geophysicists, Department of Consumer Affairs, 1998, Guidelines for Geophysical Reports for Environmental and Engineering Geology, 5 pp.
Cao, T., Bryant, W.A., Rowshandel, B., Branum, D., and Wills, C.J., 2003, The Revised 2002 California Probabilistic Seismic Hazard Maps, June 2003, California Geological Survey.
City of Stanton, 2008, City of Stanton General Plan, Chapter 6- Community Health and Safety, 80 pp,
Field, E.H., et al., 2013, Uniform California Earthquake Rupture Forecast, Version 3 (UCERF3)—The Time-Independent Model, U.S.G.S. Open-File Report 2103-1165, CGS Special Report 228, and Southern California Earthquake Center Publication 1792.
Geometrics, Inc., 2004, StrataVisorTM NZXP Operation Manual, Revision B, San Jose, California, 234 pp.
Geometrics, Inc., 2021, SeisImager/SW Analysis of Surface Waves, Pickwin Version
6.0.2.1. and WaveEq Version 5.2.6.0.
Google™ Earth, 2023, http://earth.google.com/, Version 7.3.6.9345 (64-bit).
John R. Byerly, Inc., 2023, Geotechnical Investigation, Norm Ross Sports Complex, Proposed Park Building and Bridge Over Storm Channel, 11111 Cedar Street, Stanton, California, File No. S-14556, dated February 27, 2023.
Larson, R., and Slosson, J., 1992, The Role of Seismic Hazard Evaluation in Engineering Reports, in Engineering Geology Practice in Southern California, AEG Special Publication No. 4, pp. 191-194.
Louie, J.N., 2001, Faster, Better: Shear-Wave Velocity to 100 Meters Depth From Refraction Microtremor Arrays, in, Bulletin of the Seismological Society of America, Volume 91, pp. 347-364.
Enclosure 9, Page 40
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Martin, R.C., and Davis, J.F., 1982, Status of Volcanic Prediction and Emergency Response Capabilities in Volcanic Hazard Zones of California, C.D.M.G. Special Publication 63.
Mendenhall, W.C., 1905, Development of Underground Waters in the Central Coastal Plain Region of Southern California, U.S.G.S. Water-Supply and Irrigation Paper No. 138, 105 p.
Okada, H., 2003, The Microtremor Survey Method, Society of Exploration Geophysicists, Geophysical Monograph Series Number 12, 135 pp.
Park, C.B, Milner, R.D., Rynden, N., Xia, J., and Ivanov, J., 2005, Combined use of Active and Passive Surface Waves, in, Journal of Environmental and Engineering Geophysics, Volume 10, Issue 3, pp. 323-334.
Petersen, M.D. et al., 2008, Documentation for the 2008 Update of the United States National Seismic Hazard Maps, United States Geological Survey Open-File Report 2008-1128.
Shaw J.H., Plesch, A., Dolan, J.F., Pratt, T.L., and Fiore, P., 2002, Puente Hills BlindThrust System, Los Angeles, California, in, Bulletin of the Seismological Society of America, Vol. 92, No. 8, pp.2946-2960, December 2002.
Sydnor, R.H., 2004, Engineering Geology and Seismology for Public School and Hospitals; to Accompany California Geological Survey Note 48 Checklist, 264 pp.
Toppozada, T.R., et al., 1981, Preparation of Isoseismal Maps and Summaries of Reported Effects for pre-1900 California Earthquakes, C.D.M.G. Open File Report 81-11.
Toppozada, T.R., and Parke, D.L., 1982, Areas Damaged by California Earthquakes, 1900 - 1949, C.D.M.G. Open File Report 82-17.
United States Army Corp of Engineers, 2023, National Inventory of Dams, Website Version 3.21.0; API Version 3.21.0, https://nid.sec.usace.army.mil/#/.
United States Environmental Protection Agency (EPA), 1993, EPA’s Map of Radon Zones, California, Manual 402-R-93-025, 78 pp.
United States Geological Survey (U.S.G.S.), 2023, Hazard Spectrum Application, Version 1.5.2, http://opensha.org.
United States Geological Survey (U.S.G.S.), 2023a, ANSS Comprehensive Earthquake Catalog (ComCat), https://earthquake.usgs.gov/data/comcat/.
United States Geological Survey (U.S.G.S.), 2023b, Quaternary Faults and Folds in the U.S. database, https://earthquake.usgs.gov/static/lfs/nshm/qfaults/qfaults.kmz.
Enclosure 9, Page 41
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United States Geological Survey (U.S.G.S.), 2023c, National Water Information Service:
Web Interface, Groundwater Levels for the Nation, updated March 2023 http://nwis.waterdata.usgs.gov/nwis/gwlevels?.
Welsh, James L., 1986, Ground Water Management in the Central and West Coast Basins of Los Angeles Counties, in, Hydrology of Southern California, Geological Society of America Volume and Guide Book, Field Trip No. 17, pp. 43-50.
Ziony, J.I., and Yerkes, R.F., 1985, Evaluating Earthquake and Surface Faulting Potential, in Evaluating Earthquake Hazards in the Los Angeles Region, U.S.G.S. Professional Paper 1360.
MAPS UTILIZED
California Division of Mines & Geology (C.D.M.G.), 1969, Geologic Map of California, Santa Ana Sheet, Scale 1: 250,000.
California Division of Mines & Geology (C.D.M.G.), 1998, Official Map of Seismic Hazard Zones, Anaheim Quadrangle, Scale 1:24,000.
California Division of Mines & Geology (C.D.M.G.), 1986, Earthquake Fault Zone Map, Seal Beach Quadrangle, Scale 1:24,000.
California Geological Survey (CGS), 2012, Geologic Compilation of Quaternary Surficial Deposits in Southern California, Santa Ana 30’ X 60’ Quadrangle, CGS Special Report 217, Plate 16, Scale 1: 100,000.
California Geological Survey, 2014, Tsunami Inundation Maps, California Department of Conservation, http://www.quake.ca.gov/gmaps/tsunami/tsunami_maps.htm.
California Geological Survey (CGS), 2018, Earthquake Zones of Required Investigation, Anaheim Quadrangle, Seismic hazards Zone Official Map released 1998, Scale 1:
24,000.
Federal Emergency Management Agency (FEMA), 2009, Community Panel Number 06059C0136J, December 3, 2009, Scale 1: 24,000.
Greenwood, R.B., and Morton, D.M., 1991, Geologic Map of the Santa Ana 1:100,000 Quadrangle, California, C.D.M.G. Open File Report 91-17.
Gutierrez, C., Bryant, W.A., Saucedo, G., and Wills, C., 2010, Fault Activity Map of California, Scale 1: 750,000, California Geological Survey, Geologic Data Map No. 6.
Scale 1:750,000.
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Jennings, C.W., 1994, Fault Activity Map of California and Adjacent Areas, Scale 1:
750,000, C.D.M.G. Geologic Data Map No. 8.
Morton, P.K., and Miller, R.V., 1981, Geologic Map of Orange County, California, C.D.M.G. Bulletin 204, Plate 1, Scale 1: 48,000, Showing Mines and Mineral Deposits.
Morton, D.M., 1999, Preliminary Digital Geologic Map of the Santa Ana 30’ x 60’ Quadrangle, Southern California, Scale 1: 100,000, U.S.G.S. Open-File Report 99-172, Version 1.0.
Morton, D.M. and Miller, F.K., 2006, Preliminary Geologic Map of the San Bernardino and Santa Ana 30’ x 60’ Quadrangles, California, Scale 1: 100,000, U.S.G.S. Open-File Report 2006-1217, 6 sheets, Version 1.0.
Ziony, J.I., and Jones, L.M., 1989, Map Showing Late Quaternary Faults and 1978-1984 Seismicity of the Los Angeles Region, California, U.S.G.S. Miscellaneous Field Studies Map MF-1964.
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N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
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N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
February 2025
Appendix D Paleontological Resources Records
Search
Research & Collections
e-mail: [email protected]
March 26, 2023
re: Paleontological resources for the Norm Ross Sports Complex Joint Use Project I have conducted a thorough search of our paleontology collection records for the locality and specimen data for proposed development at the Norm Ross Sports Complex Joint Use project area as outlined on the portion of the Anaheim USGS topographic quadrangle map that you sent to me via e-mail on March 17, 2023. We do not have any fossil localities that lie directly within the proposed project area, but we do have fossil localities nearby from the same sedimentary deposits that occur in the proposed project area, either at the surface or at depth.
The following table shows the closest known localities in the collection of the Natural History Museum of Los Angeles County (NHMLA).
Locality
Number Location Formation Taxa Depth
LACM IP 4933
Near the intersection
of Navajo Rd &
Meinhardt Rd Niguel Formation Invertebrates (unspecified) Unknown LACM IP 4560
east of Hwy. 39;
north from Rosecrans
Ave.; near L.A. -
Orange Co. line Unknown (Pliocene) Pecten caurinus Gould surface in
stream bed
LACM VP 4185-
4201
Coyote Creek,
adjacent to Ralph B
Clark Regional Park in
West Coyote Hills
La Habra Formation
(Pleistocene; sandy
silt shot through with
caliche)
Bison (Bison), camel (Camelops),
horse (Equus), mammoth
(Mammuthus), mastodon (Mamut),
elephant clade (Proboscidea), dire
wolf (Canis dirus), Coyote (C.
latrans), deer (Odocoileus), dwarf
pronghorn
(Capromeryx),unidentified
artiodactyl; sea duck (Chendytes)
Surface, in
creek bed
LACM VP 1652
Rio Vista Avenue
south of Lincoln
Avenue Alluvium (Pleistocene) Sheep (Ovis)
Unknown
(excavations
for housing
project)
LACM VP 65113
5092 Wintersburg
Road; Huntington
Beach
Unknown formation
(Pleistocene)
Mammoth (Mammuthus), bison
(Bison); uncatalogued invertebrates
6 - 20 feet
bgs
LACM VP 3291
Sunset Beach at low
tide, 50 yards north of
Anderson Street &
west of Pacific Coast
Highway
Unknown Formation
(Pleistocene) Camel (Camelops hesternus) Surface
VP, Vertebrate Paleontology; IP, Invertebrate Paleontology; bgs, below ground surface This records search covers only the records of the NHMLA. It is not intended as a paleontological assessment of the project area for the purposes of CEQA or NEPA. Potentially fossil-bearing units are present in the project area, either at the surface or in the subsurface. As such, NHMLA recommends that a full paleontological assessment of the project area be conducted by a paleontologist meeting Bureau of Land Management or Society of Vertebrate Paleontology standards.
Sincerely,
Alyssa Bell, Ph.D.
Natural History Museum of Los Angeles County
enclosure: invoice
N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
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N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
February 2025
Appendix E Noise Assessment
Fundamentals of Noise
NOISE
Noise is most often defined as unwanted sound; whether it is loud, unpleasant, unexpected, or otherwise undesirable. Although sound can be easily measured, the perception of noise and the physical response to sound complicate the analysis of its impact on people. People judge the relative magnitude of sound sensation in subjective terms such as “noisiness” or “loudness.”
Noise Descriptors
The following are brief definitions of terminology used in this chapter:
▪ Sound. A disturbance created by a vibrating object, which, when transmitted by pressure waves through a medium such as air, is capable of being detected by a receiving mechanism, such as the human ear or a microphone.
▪ Noise. Sound that is loud, unpleasant, unexpected, or otherwise undesirable. ▪ Decibel (dB). A unitless measure of sound, expressed on a logarithmic scale and with respect to a defined reference sound pressure. The standard reference pressure is 20 micropascals (20 µPa). ▪ Vibration Decibel (VdB). A unitless measure of vibration, expressed on a logarithmic scale and with respect to a defined reference vibration velocity. In the U.S., the standard reference velocity is 1 microinch per second (1x10-6 in/sec).
▪ A-Weighted Decibel (dBA). An overall frequency-weighted sound level in decibels that approximates the frequency response of the human ear.
▪ Equivalent Continuous Noise Level (Leq); also called the Energy-Equivalent Noise Level. The value of an equivalent, steady sound level which, in a stated time period (often over an hour) and at a stated location, has the same A-weighted sound energy as the time-varying sound. Thus, the Leq metric is a single numerical value that represents the equivalent amount of variable sound energy received by a receptor over the specified duration.
▪ Statistical Sound Level (Ln). The sound level that is exceeded “n” percent of time during a given sample period. For example, the L50 level is the statistical indicator of the time-varying noise signal that is exceeded 50 percent of the time (during each sampling period); that is, half of the sampling time, the changing noise levels are above this value and half of the time they are below it. This is called the “median sound level.” The L10 level, likewise, is the value that is exceeded 10 percent of the time (i.e., near the maximum) and this is often known as the “intrusive sound level.” The L90 is the sound level exceeded 90 percent of the time and is often considered the “effective background level” or “residual noise level.”
▪ Maximum Sound Level (Lmax). The highest RMS sound level measured during the measurement period.
▪ Root Mean Square Sound Level (RMS). The square root of the average of the square of the sound pressure over the measurement period.
▪ Day-Night Sound Level (Ldn or DNL). The energy-average of the A-weighted sound levels occurring during a 24-hour period, with 10 dB added to the sound levels occurring during the period from 10:00 PM to 7:00 AM.
▪ Community Noise Equivalent Level (CNEL). The energy average of the A-weighted sound levels occurring during a 24-hour period, with 5 dB added from 7:00 PM to 10:00 PM and 10 dB from 10:00 PM to 7:00 AM. NOTE: For general community/environmental noise, CNEL and Ldn values rarely differ by more than 1 dB (with the CNEL being only slightly more restrictive – that is, higher than the Ldn value). As a matter of practice, Ldn and CNEL values are interchangeable and are treated as equivalent in this assessment.
▪ Peak Particle Velocity (PPV). The peak rate of speed at which soil particles move (e.g., inches per second) due to ground vibration.
▪ Sensitive Receptor. Noise- and vibration-sensitive receptors include land uses where quiet environments are necessary for enjoyment and public health and safety. Residences, schools, motels and hotels, libraries, religious institutions, hospitals, and nursing homes are examples.
Characteristics of Sound
When an object vibrates, it radiates part of its energy in the form of a pressure wave. Sound is that pressure wave transmitted through the air. Technically, airborne sound is a rapid fluctuation or oscillation of air pressure above and below atmospheric pressure that creates sound waves.
Sound can be described in terms of amplitude (loudness), frequency (pitch), or duration (time). Loudness or amplitude is measured in dB, frequency or pitch is measured in Hertz [Hz] or cycles per second, and duration or time variations is measured in seconds or minutes.
Amplitude
Unlike linear units such as inches or pounds, decibels are measured on a logarithmic scale. Because of the physical characteristics of noise transmission and perception, the relative loudness of sound does not closely match the actual amounts of sound energy. Table 1 presents the subjective effect of changes in sound pressure levels. Ambient sounds generally range from 30 dBA (very quiet) to 100 dBA (very loud). Changes of 1 to 3 dB are detectable under quiet, controlled conditions, and changes of less than 1 dB are usually not discernible (even under ideal conditions). A 3 dB change in noise levels is considered the minimum change that is detectable with human hearing in outside environments. A change of 5 dB is readily discernible to most people in an exterior environment, and a 10 dB change is perceived as a doubling (or halving) of the sound.
Table 1 Noise Perceptibility
Change in dB Noise Level
± 3 dB Barely perceptible increase
± 5 dB Readily perceptible increase
± 10 dB Twice or half as loud
± 20 dB Four times or one-quarter as loud
Source: California Department of Transportation (Caltrans). 2013, September. Technical Noise Supplement (“TeNS”).
Frequency
The human ear is not equally sensitive to all frequencies. Sound waves below 16 Hz are not heard at all, but are “felt” more as a vibration. Similarly, though people with extremely sensitive hearing can hear sounds as high as 20,000 Hz, most people cannot hear above 15,000 Hz. In all cases, hearing acuity falls off rapidly above about 10,000 Hz and below about 200 Hz.
When describing sound and its effect on a human population, A-weighted (dBA) sound levels are typically used to approximate the response of the human ear. The A-weighted noise level has been found to correlate well with people’s judgments of the “noisiness” of different sounds and has been used for many years as a measure of community and industrial noise. Although the A-weighted scale and the energy-equivalent metric are commonly used to quantify the range of human response to individual events or general community sound levels, the degree of annoyance or other response also depends on several other perceptibility factors, including:
▪ Ambient (background) sound level
▪ General nature of the existing conditions (e.g., quiet rural or busy urban) ▪ Difference between the magnitude of the sound event level and the ambient condition ▪ Duration of the sound event
▪ Number of event occurrences and their repetitiveness
▪ Time of day that the event occurs
Duration
Time variation in noise exposure is typically expressed in terms of a steady-state energy level equal to the energy content of the time varying period (called Leq), or alternately, as a statistical description of the sound level that is exceeded over some fraction of a given observation period. For example, the L50 noise level represents the noise level that is exceeded 50 percent of the time; half the time the noise level exceeds this level and half the time the noise level is less than this level. This level is also representative of the level that is exceeded 30 minutes in an hour. Similarly, the L2, L8 and L25 values represent the noise levels that are exceeded 2, 8, and 25 percent of the time or 1, 5, and 15 minutes per hour, respectively. These “n” values are typically used to demonstrate compliance for stationary noise sources with many cities’ noise ordinances.
Other values typically noted during a noise survey are the Lmin and Lmax. These values represent the minimum and maximum root-mean-square noise levels obtained over the measurement period, respectively.
Because community receptors are more sensitive to unwanted noise intrusion during the evening and at night, state law and many local jurisdictions use an adjusted 24-hour noise descriptor called the Community Noise Equivalent Level (CNEL) or Day-Night Noise Level (Ldn). The CNEL descriptor requires that an artificial increment (or “penalty”) of 5 dBA be added to the actual noise level for the hours from 7:00 PM to 10:00 PM and 10 dBA for the hours from 10:00 PM to 7:00 AM. The Ldn descriptor uses the same methodology except that there is no artificial increment added to the hours between 7:00 PM and 10:00 PM. Both descriptors give roughly the same 24-hour level, with the CNEL being only slightly more restrictive (i.e., higher). The CNEL or Ldn metrics are commonly applied to the assessment of roadway and airport-related noise sources.
Sound Propagation
Sound dissipates exponentially with distance from the noise source. This phenomenon is known as “spreading loss.” For a single-point source, sound levels decrease by approximately 6 dB for each doubling of distance from the source (conservatively neglecting ground attenuation effects, air absorption factors, and barrier shielding). For example, if a backhoe at 50 feet generates 84 dBA, at 100 feet the noise level would be 79 dBA, and at 200 feet it would be 73 dBA. This drop-off rate is appropriate for noise generated by on-site operations from stationary equipment or activity at a project site. If noise is produced by a line source, such as highway traffic, the sound decreases by 3 dB for each doubling of distance over a reflective (“hard site”) surface such as concrete or asphalt. Line source noise in a relatively flat environment with ground-level absorptive vegetation decreases by an additional 1.5 dB for each doubling of distance.
Psychological and Physiological Effects of Noise
Physical damage to human hearing begins at prolonged exposure to noise levels higher than 85 dBA.
Exposure to high noise levels affects the entire system, with prolonged noise exposure in excess of 75 dBA increasing body tensions, thereby affecting blood pressure and functions of the heart and the nervous system.
Extended periods of noise exposure above 90 dBA results in permanent cell damage, which is the main driver for employee hearing protection regulations in the workplace. For community environments, the ambient or background noise problem is widespread, through generally worse in urban areas than in outlying, lessdeveloped areas. Elevated ambient noise levels can result in noise interference (e.g., speech interruption/masking, sleep disturbance, disturbance of concentration) and cause annoyance. Since most people do not routinely work with decibels or A-weighted sound levels, it is often difficult to appreciate what a given sound pressure level number means. To help relate noise level values to common experience, Table 2 shows typical noise levels from familiar sources.
Table 2 Typical Noise Levels
Common Outdoor Activities
Noise Level
(dBA) Common Indoor Activities
Onset of physical discomfort 120+
110 Rock Band (near amplification system)
Jet Flyover at 1,000 feet
100
Gas Lawn Mower at three feet
90 Diesel Truck at 50 feet, at 50 mph Food Blender at 3 feet 80 Garbage Disposal at 3 feet
Noisy Urban Area, Daytime
70 Vacuum Cleaner at 10 feet
Commercial Area Normal speech at 3 feet
Heavy Traffic at 300 feet 60
Large Business Office
Quiet Urban Daytime 50 Dishwasher Next Room
Quiet Urban Nighttime 40 Theater, Large Conference Room (background) Quiet Suburban Nighttime
30 Library
Quiet Rural Nighttime Bedroom at Night, Concert Hall (background) 20 Broadcast/Recording Studio
10 Lowest Threshold of Human Hearing 0 Lowest Threshold of Human Hearing Source: California Department of Transportation (Caltrans). 2013, September. Technical Noise Supplement (“TeNS”).
Vibration Fundamentals
Vibration is an oscillatory motion through a solid medium in which the motion’s amplitude can be described in terms of displacement, velocity, or acceleration. Vibration is normally associated with activities stemming from operations of railroads or vibration-intensive stationary sources, but can also be associated with construction equipment such as jackhammers, pile drivers, and hydraulic hammers. As with noise, vibration can be described by both its amplitude and frequency. Vibration displacement is the distance that a point on a surface moves away from its original static position; velocity is the instantaneous speed that a point on a surface moves; and acceleration is the rate of change of the speed. Each of these descriptors can be used to correlate vibration to human response, building damage, and acceptable equipment vibration levels. During construction, the operation of construction equipment can cause groundborne vibration. During the operational phase of a project, receptors may be subject to levels of vibration that can cause annoyance due to noise generated from vibration of a structure or items within a structure.
Vibration amplitudes are usually described in terms of either the peak particle velocity (PPV) or the root mean square (RMS) velocity. PPV is the maximum instantaneous peak of the vibration signal and RMS is the square root of the average of the squared amplitude of the signal. PPV is more appropriate for evaluating potential building damage and RMS is typically more suitable for evaluating human response.
As with airborne sound, annoyance with vibrational energy is a subjective measure, depending on the level of activity and the sensitivity of the individual. To sensitive individuals, vibrations approaching the threshold of perception can be annoying. Persons accustomed to elevated ambient vibration levels, such as in an urban environment, may tolerate higher vibration levels. Table 3 displays the human response and the effects on buildings resulting from continuous vibration (in terms of various levels of PPV).
Table 3 Human Reaction to Typical Vibration Levels
Vibration Level,
PPV (in/sec) Human Reaction Effect on Buildings
0.006–0.019 Threshold of perception, possibility of intrusion Vibrations unlikely to cause damage of any type
0.08 Vibrations readily perceptible Recommended upper level of vibration to which ruins and ancient monuments should be subjected
0.10 Level at which continuous vibration begins to annoy people
Virtually no risk of “architectural” (i.e. not structural) damage to normal buildings
0.20 Vibrations annoying to people in buildings
Threshold at which there is a risk to “architectural”
damage to normal dwelling – houses with plastered
walls and ceilings
0.4–0.6
Vibrations considered unpleasant by people
subjected to continuous vibrations and unacceptable
to some people walking on bridges
Vibrations at a greater level than normally expected
from traffic, but would cause “architectural” damage
and possibly minor structural damage
Source: California Department of Transportation (Caltrans). 2020, April. Transportation and Construction Vibration Guidance Manual. Prepared by ICF International.
LOCAL REGULATIONS AND STANDARDS
COMMUNITY HEALTH & SAFETY
Stanton General Plan 6-11
NOISE
The Noise Element of the General Plan provides a framework to limit noise exposure within the city. Existing and future noise environments and the compatibility of land uses are considered in the Element, as well as sensitive receptors and generators of stationary noise. Projected noise levels are included to help guide future land use policy and prevent high noise levels in sensitive areas at build-out. In addition, noise contours in the form of community noise equivalent level (CNEL) or day-night average level (Ldn) are provided for all referenced sources.
Various measures are described in order to mitigate potential noise conflicts. These measures are designed to lessen impacts from unavoidable noise conflicts within the city. The Noise Element also serves as a guideline for compliance with the State’s Noise Insulation Standards.
The State of California requires every jurisdiction to include a Noise element in their General Plan.
The Noise element for this General Plan presents several different aspects of noise evaluation.
The city’s goals, objectives, and policies for meeting noise standards are first identified, and then the method in which the noise levels are measured are described. The most general ways to quantify noise levels are by CNEL, Leq, and Ldn, which are measured in decibels using the Aweighted sound pressure level (dBA). These measures are discussed in more detail below.
Also presented in the Noise element are Federal, State, and Local noise standards, and related laws, standards, ordinances, and regulations, such as the U.S. Noise Control Act and California Office of Planning and Research Guidelines.
Noise in Stanton comes from two primary sources: transportation and non-transportation noise sources. Noise levels associated with mobile sources or transportation noise can be reliably predicted using formulas that take into account traffic volume, speed and percentage of trucks.
Stationary or non-transportation noise sources include commercial and industrial land uses located near residential areas currently generate occasional noise impacts. The primary noise sources associated with these facilities are caused by delivery trucks, air compressors, generators, outdoor loudspeakers and gas venting. Residential land uses and areas identified as noise-sensitive must be protected from excessive noise from transportation and non-transportation noise sources.
Noise Scale and Definitions
Sound is described in terms of the loudness (amplitude) of the sound and frequency (pitch) of the sound. The standard unit of measurement of the loudness of sound is the decibel (dB). Since the human ear is not equally sensitive to sound at all frequencies, a special frequency-dependent rating scale has been devised to relate noise to human sensitivity. The A-weighted decibel scale (dBA) performs this compensation by differentiating among frequencies in a manner approximating the sensitivity of the human ear.
Decibels are based on the logarithmic scale. The logarithmic scale compresses the wide range in sound pressure levels to a more usable range of numbers in a manner similar to the Richter scale used to measure earthquakes. In terms of human response to noise, a sound 10 dBA higher than another is perceived to be twice as loud and 20 dBA higher is perceived to be four times as loud, and so forth. Everyday sounds normally range from 30 dBA (very quiet) to 100 dBA (very loud).
Examples of various sound levels in different environments are illustrated on Exhibit 6-6, Common Environmental Noise Levels.
6-12
Many methods have been developed for evaluating community noise to account for, among other things:
The variation of noise levels over time;
The influence of periodic individual loud events; and The community response to changes in the community noise environment.
Table 6-1, Noise Descriptors, provides a listing of methods to measure sound over a period of time.
Table 6-1
Noise Descriptors
Term Definition
Decibel (dB) The unit for measuring the volume of sound equal to 10 times the logarithm (base 10) of the ratio of the pressure of a measured sound to a reference pressure (20 micropascals).
A-Weighted Decibel (dBA) A sound measurement scale that adjusts the pressure of individual frequencies according to human sensitivities. The scale accounts for the fact that the region of highest sensitivity for the human ear is between 2,000 and 4,000 cycles per second (hertz).
Equivalent Sound Level (Leq) The sound level containing the same total energy as a time varying signal over a given time period. The Leq is the value that expresses the time averaged total energy of a fluctuating sound level.
Maximum Sound Level (Lmax) The highest individual sound level (dBA) occurring over a given time period.
Minimum Sound Level (Lmin) The lowest individual sound level (dBA) occurring over a given time period.
Community Noise Equivalent
Level (CNEL)
A rating of community noise exposure to all sources of sound that differentiates between daytime, evening, and nighttime noise exposure. These adjustments are +5 dBA for the evening, 7:00 p.m. to 10:00 p.m., and +10 dBA for the night, 10:00 p.m. to 7:00 a.m..
Day/Night Average (Ldn) The Ldn is a measure of the 24-hour average noise level at a given location. It was adopted by the U.S. Environmental Protection Agency for developing criteria for the evaluation of community noise exposure. It is based on a measure of the average noise level over a given time period called the Leq. The Ldn is calculated by averaging the Leq’s for each hour of the day at a given location after penalizing the “sleeping hours” (defined as 10:00 p.m. to 7:00 a.m.) by 10 dBA to account for the increased sensitivity of people to noises that occur at night.
Exceedance Level (Ln) The A-weighted noise levels that are exceeded 1%, 10%, 50%, and 90% (L01, L10, L50, L90, respectively) of the time during the measurement period.
Source: Cyril M. Harris, Handbook of Noise Control, 1979.
COMMUNITY HEALTH & SAFETY
Stanton General Plan 6-13
Health Effects of Noise
Human response to sound is highly individualized. Annoyance is the most common issue regarding community noise. The percentage of people claiming to be annoyed by noise generally increases with the environmental sound level. However, many factors also influence people’s response to noise. The factors can include the character of the noise, the variability of the sound level, the presence of tones or impulses, and the time of day of the occurrence. Additionally, non-acoustical factors, such as the person’s opinion of the noise source, the ability to adapt to the noise, the attitude towards the source and those associated with it, and the predictability of the noise, all influence people’s response. As such, response to noise varies widely from one person to another and with any particular noise, individual responses will range from “not annoyed” to “highly annoyed.”
When the noise level of an activity rises above 70 dBA, the chance of receiving a complaint is possible, and as the noise level rises, dissatisfaction among the public steadily increases. However, an individual’s reaction to a particular noise depends on many factors, such as the source of the sound, its loudness relative to the background noise, and the time of day. The reaction to noise can also be highly subjective; the perceived effect of a particular noise can vary widely among individuals in a community.
The effects of noise are often only transitory, but adverse effects can be cumulative with prolonged or repeated exposure. The effects of noise on the community can be organized into six broad categories:
Noise-Induced Hearing Loss;
Interference with Communication;
Effects of Noise on Sleep;
Effects on Performance and Behavior;
Extra-Auditory Health Effects; and
Annoyance.
Although it often causes discomfort and sometimes pain, noise-induced hearing loss usually takes years to develop. Noise-induced hearing loss can impair the quality of life through a reduction in the ability to hear important sounds and to communicate with family and friends. Hearing loss is one of the most obvious and easily quantified effects of excessive exposure to noise. While the loss may be temporary at first, it could become permanent after continued exposure. When combined with hearing loss associated with aging, the amount of hearing loss directly caused by the environment is difficult to quantify. Although the major cause of noise-induced hearing loss is occupational, substantial damage can be caused by non-occupational sources. 6-14
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According to the United States Public Health Service, nearly ten million of the estimated 21 million Americans with hearing impairments owe their losses to noise exposure. Noise can mask important sounds and disrupt communication between individuals in a variety of settings. This process can cause anything from a slight irritation to a serious safety hazard, depending on the circumstance. Noise can disrupt face-to-face communication and telephone communication, and the enjoyment of music and television in the home. It can also disrupt effective communication between teachers and pupils in schools, and can cause fatigue and vocal strain in those who need to communicate in spite of the noise.
Interference with communication has proved to be one of the most important components of noise-related annoyance. Noise-induced sleep interference is one of the critical components of community annoyance. Sound level, frequency distribution, duration, repetition, and variability can make it difficult to fall asleep and may cause momentary shifts in the natural sleep pattern, or level of sleep. It can produce short-term adverse effects on mood changes and job performance, with the possibility of more serious effects on health if it continues over long periods. Noise can cause adverse effects on task performance and behavior at work, and non-occupational and social settings. These effects are the subject of some controversy, since the presence and degree of effects depends on a variety of intervening variables. Most research in this area has focused mainly on occupational settings, where noise levels must be sufficiently high and the task sufficiently complex for effects on performance to occur.
Recent research indicates that more moderate noise levels can produce disruptive after-effects, commonly manifested as a reduced tolerance for frustration, increased anxiety, decreased incidence of “helping” behavior, and increased incidence of “hostile” behavior. Noise has been implicated in the development or exacerbation of a variety of health problems, ranging from hypertension to psychosis. As with other categories, quantifying these effects is difficult due to the amount of variables that need to be considered in each situation. As a biological stressor, noise can influence the entire physiological system. Most effects seem to be transitory, but with continued exposure some effects have been shown to be chronic in laboratory animals.
Annoyance can be viewed as the expression of negative feelings resulting from interference with activities, as well as the disruption of one’s peace of mind and the enjoyment of one’s environment. Field evaluations of community annoyance are useful for predicting the consequences of planned actions involving highways, airports, road traffic, railroads, or other noise sources. The consequences of noise-induced annoyance are privately held dissatisfaction, publicly expressed complaints to authorities, and potential adverse health effects, as discussed above. In a study conducted by the United States Department of Transportation, the effects of annoyance to the community were quantified. In areas where noise levels were consistently above 60 dBA CNEL, approximately nine percent of the community is highly annoyed. When levels exceed 65 dBA CNEL, that percentage rises to 15 percent. Although evidence for the various effects of noise have differing levels of certainty, it is clear that noise can affect human health. Most of the effects are, to a varying degree, stress related.
Laws, Ordinances, Regulations, and Standards
Land uses deemed sensitive by the State of California (State) include schools, hospitals, rest homes, and long-term care and mental care facilities. Many jurisdictions also consider residential uses particularly noise-sensitive because families and individuals expect to use time in the home for rest and relaxation, and noise can interfere with those activities. Some jurisdictions may also 6-16
identify other noise-sensitive uses such as churches, libraries, and parks. Land uses that are relatively insensitive to noise include office, commercial, and retail developments. There is a range of insensitive noise receptors that include uses that generate significant noise levels and that typically have a low level of human occupancy.
This noise analysis was conducted in accordance with Federal, State, and local criteria described in the following sections.
Federal Noise Standards
The United States Noise Control Act of 1972 (NCA) recognized the role of the Federal government in dealing with major commercial noise sources in order to provide for uniform treatment of such sources. As Congress has the authority to regulate interstate and foreign commerce, regulation of noise generated by such commerce also falls under congressional authority. The Federal government specifically preempts local control of noise emissions from aircraft, railroad and interstate highways.
U.S. Environmental Protection Agency
The EPA offers guidelines for community noise exposure in the publication Noise Effects Handbook – A Desk Reference to Health and Welfare Effects of Noise. These guidelines consider occupational noise exposure as well as noise exposure in homes. The EPA recognizes an exterior noise level of 55 dB Ldn as a general goal to protect the public from hearing loss, activity interference, sleep disturbance, and annoyance. The EPA and other Federal agencies have adopted suggested land use compatibility guidelines that indicate that residential noise exposures of 55 to 65 dB Ldn are acceptable. The EPA notes, however, that these levels are not regulatory goals, but are levels defined by a negotiated scientific consensus, without concern for economic and technological feasibility or the needs and desires of any particular community.
State of California
The State Office of Planning and Research Noise Element Guidelines include recommended exterior and interior noise level standards for local jurisdictions to identify and prevent the creation of incompatible land uses due to noise. The Office of Planning and Research Noise Element Guidelines contain a land use compatibility table that describes the compatibility of various land uses with a range of environmental noise levels in terms of community noise equivalent level (CNEL). A CNEL is defined as the 24-hour average noise level measured in A-weighted sound pressure level for a 24-hour period with different weighting factors for the noise levels occurring during the day, evening, and nighttime periods. A noise environment of 50 to 60 CNEL is considered to be “normally acceptable” for residential uses. The Office of Planning and Research recommendations also note that, under certain conditions, more restrictive standards than the maximum levels cited may be appropriate. As an example, the standards for quiet suburban and rural communities may be reduced by 5 to 10 dB to reflect their lower existing outdoor noise levels in comparison with urban environments. Table 6-2, Land Use Compatibility Noise Guidelines – California, illustrates the State guidelines established by the State Department of Health Services for acceptable noise levels for each county and city.
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Table 6-2
Land Use Compatibility Noise Guidelines — California
Community Noise Exposure (Ldn or CNEL, dBA)
Land Use Category Normally
Acceptable
Conditionally
Acceptable
Normally
Unacceptable
Clearly
Unacceptable
Residential - Low Density, Single-Family,
Duplex, Mobile Homes 50 - 60 55 - 70 70-75 75-85
Residential - Multiple Family 50 - 65 60 - 70 70 - 75 70 - 85 Transient Lodging - Motels, and Hotels 50 - 65 60 - 70 70 - 80 80 - 85 Schools, Libraries, Churches, Hospitals,
Nursing Homes 50 - 70 60 - 70 70 - 80 80 - 85
Auditoriums, Concert Halls,
Amphitheaters NA 50 - 70 NA 65 - 85
Sports Arenas, Outdoor Spectator Sports NA 50 - 75 NA 70 - 85 Playgrounds, Neighborhood Parks 50 - 70 NA 67.5 - 75 72.5 - 85 Golf Courses, Riding Stables, Water
Recreation, Cemeteries 50 - 70 NA 70 - 80 80 - 85
Office Buildings, Business Commercial and
Professional 50 - 70 67.5 - 77.5 75 - 85 NA
Industrial, Manufacturing, Utilities,
Agriculture 50 - 75 70 - 80 75 - 85 NA
NA: Not Applicable
Source: General Plan Guidelines, Office of Planning and Research, California, October 2003.
Normally Acceptable – Specified land use is satisfactory, based upon the assumption that any buildings involved are of normal conventional construction, without any special noise insulation requirements.
Conditionally Acceptable – New construction or development should be undertaken only after a detailed analysis of the noise reduction requirements is made and needed noise insulation features included in the design. Conventional construction, but with closed windows and fresh air supply systems or air conditioning, will normally suffice.
Normally Unacceptable – New construction or development should be discouraged. If new construction or development does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise insulation features included in the design.
Clearly Unacceptable – New construction or development should generally not be undertaken.
City Noise Standards
The city of Stanton maintains a comprehensive Noise Control Ordinance within the Municipal Code that sets standards for noise levels citywide and provides the means to enforce the reduction of obnoxious or offensive noises. Chapter 9.28 of the Stanton Municipal Code establishes noise standards and enforcement procedures.
The city of Stanton has adopted a local Noise Control Ordinance (Municipal Code 9.28) in order to control unnecessary, excessive, and annoying sounds emanating from incorporated areas of the city. The Ordinance is designed to control unnecessary, excessive, and annoying sounds in residential neighborhoods by the following noise standards:
Exterior and interior noise of 55 dBA during the hours of 7:00 a.m. to 10:00 p.m.; Exterior noise of 50 dBA during the hours of 10:00 p.m. to 7:00 a.m.; and, Interior noise of 45 dBA during the hours of 10:00 p.m. to 7:00 a.m.
The Ordinance prohibits exterior noise sources to exceed the following:
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The noise standard for a cumulative period of more than thirty minutes in any hour; or The noise standard plus 5 dB(A) for a cumulative period of more than fifteen minutes in any hour; or
The noise standard plus 10 dB(A) for a cumulative period of more than five minutes in any hour; or
The noise standard plus 15 dB(A) for a cumulative period of more than one minute in any hour; or
The noise standard plus 20 dB(A) for any period of time.
Interior noise sources cannot exceed the following:
The interior noise standard for a cumulative period of more than five minutes in any hour; or
The interior noise standard plus 5 dB(A) for a cumulative period of more than one minute in any hour; or
The interior noise standard plus 10 dB(A) for any period of time.
Noise Analysis
Human response to noise varies widely depending on the type of noise, time of day, and sensitivity of the receptor. The effects of noise on humans can range from temporary or permanent hearing loss to mild stress and annoyance due to such things as speech interference and sleep deprivation. Prolonged stress, regardless of the cause, is known to contribute to a variety of health disorders. Noise, or the lack of it, is a factor in the aesthetic perception of some settings, particularly those with religious or cultural significance.
Noise impacts can be mitigated in three basic ways: by reducing the sound level of the noise generator, by increasing the distance between the source and receiver, and by insulating the receiver. Noise reduction can be accomplished by placement of walls, landscaped berms, or a combination of the two, between the noise source and the receiver. Generally, effective noise shielding requires a solid barrier with a mass of at least four pounds per square-foot of surface area which is large enough to block the line of sight between source and receiver. Variations may be appropriate in individual cases based on distance, nature and orientation of buildings behind the barrier, and a number of other factors. Garages or other buildings may be used to shield dwelling units and outdoor living areas from traffic noise.
In addition to site design techniques, noise insulation can be accomplished through proper design of buildings. Nearby noise generators should be recognized in determining the location of doors, windows and vent openings. Sound-rated windows (extra thick or multi-paned) and wall insulation are also effective. None of these measures, however, can realize their full potential unless care is taken in actual construction: doors and windows fitted properly, openings sealed, joints caulked, plumbing adequately insulated from structural members. Of course, sound-rated doors and windows will have little effect if left open. This may require installation of air conditioning for adequate ventilation. The chain of design, construction, and operation is only as effective as its weakest link.
Noise impacts can be reduced by insulating noise sensitive uses, such as residences, schools, libraries, hospitals, nursing and care homes and some types of commercial activities. But perhaps a more efficient approach involves limiting the level of noise generation at the source. State and
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Federal statutes have largely preempted local control over vehicular noise emissions but commercial and industrial operations and certain residential activities provide opportunities for local government to assist in noise abatement. Local ordinances may establish maximum levels for noise generated on-site. This usually takes the form of limiting the level of noise permitted to leave the property where it may impact other uses.
Although vehicular noise emission standards are established at the State and Federal levels, local agencies can play a significant part in reducing traffic noise by controlling traffic volume and congestion. Traffic noise is greatest at intersections due to acceleration, deceleration, and gear shifting. Measures such as signal synchronization can help to minimize this problem. Likewise, reduction of congestion aids in reduction of noise. This can be accomplished through the application of traffic engineering techniques such as channelization of turning movements, parking restrictions, separation of modes (bus, auto, bicycle, pedestrian), and restrictions on truck traffic.
Noise reduction through reduction of traffic volumes can also be accomplished with incentive programs for use of public transit facilities and high-occupancy vehicles, staggering of work hours and land use controls. Vehicle trips can be turned into pedestrian trips with integration of housing and employment into the same project or area, construction of high-density, affordable housing in proximity to employment, shopping and public transit facilities and other techniques.
FIRE PROTECTION
The Orange County Fire Authority (OCFA) is a regional fire service agency that provides fire protection services to 22 cities in Orange County, including the city of Stanton and unincorporated areas of Orange County. Established in 1956, OCFA Fire Station #46 is located at 7871 Pacific Street in Stanton. Fire Station #46 currently maintains an Engine and Paramedic Assessment Unit (PAU) with six captains, six engineers and nine firefighters. According to the OCFA, Fire Station #46 responded to 2,352 emergency incidents in 2005, which included fire, emergency medical, hazardous material, false alarms and other incidents.1 OCFA’s Dispatch Center receives and dispatches emergency calls using a Computer Aided Dispatching (CAD) system. The Mapping and Geo-file Group maintains the Fire Station Order file (a key component of CAD to ensure the closest emergency apparatus is sent to an emergency) and produces District Maps for use by emergency apparatus to respond to the emergency scenes.2 It takes approximately three to five minutes for engines to arrive on scene after an emergency (911) call has been placed.3
Fire Hazards
As growth and development continues within the city, and Orange County, urban fires become a greater threat. Within urbanized areas the incidence of structural fires increases. Some of the most difficult fire protection problems within urbanized areas are: multiple story, wood frame, high density apartment developments; large contiguous developed areas with combustible roofcovering materials, storage, handling and use of hazardous materials on site; and natural disasters.
Opportunities to reduce the incidence and effects of urban fires include adherence to the
1 Orange County Fire Authority, “Orange County Fire Authority Partner City Stanton”, www.ocfa.org (accessed October 2006).
2 Orange County Fire Authority, “Emergency Communications”, www.ocfa.org (accessed October 2006). 3 Orange County Fire Authority, “Frequently Asked Questions”, www.ocfa.org (accessed October 2006). 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
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Title 9 PEACE, SAFETY AND MORALS
Chapter 9.28 NOISE CONTROL
9.28.010 Declaration of policy.
9.28.020 Definitions.
9.28.025 Excessively loud events.
9.28.030 Noise level measurement criteria.
9.28.040 Designated noise zone.
9.28.050 Exterior noise standards.
9.28.060 Interior noise standards.
9.28.070 Special provisions.
9.28.080 Schools, hospitals and churches— Special provisions.
9.28.090 Air conditioning and refrigeration—Special provisions.
9.28.095 Special noise sources—Radios, television sets and similar devices.
9.28.096 Same—Machinery, fans and other mechanical devices.
9.28.100 Noise level measurement.
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9.28.110 Manner of enforcement.
9.28.120 Variance procedure.
9.28.130 Noise variance board.
9.28.140 Appeals.
9.28.150 Violation—Misdemeanor.
9.28.010 Declaration of policy.
A. In order to control unnecessary, excessive and annoying sounds emanating from incorporated areas of the city, it is declared to be the policy of the city to prohibit such sounds generated from all sources as specified in this chapter.
B. It is determined that certain noise levels are detrimental to the public health, welfare and safety and contrary to public interest, therefore, the city council does ordain and declare that creating, maintaining, causing or allowing to create, maintain or cause any noise in a manner prohibited by or not in conformity with the provisions of this chapter is a public nuisance and shall be punishable as such. (Prior code § 9.44.010)
9.28.020 Definitions.
The following words, phrases and terms as used in this chapter shall have the meaning as indicated below:
A. “Ambient noise level” means the all-encompassing level associated with a given environment, being a composite of sounds from all sources, excluding the alleged offensive noise, at the location and approximate time at which a comparison with the alleged offensive noise is to be made.
B. “Cumulative period” means an additive period of time composed of individual time segments which may be continuous or interrupted.
C. “Decibel” (“dB”) means a unit which denotes the ratio between two quantities which are proportional to power. The number of decibels corresponding to the ratio of two amounts of power is ten times the logarithm to the base ten of this ratio. 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 3/11 D. “Dwelling unit” means a single unit providing complete, independent living facilities for one or more persons including permanent provisions for living, sleeping, eating, cooking and sanitation.
E. “Emergency machinery, vehicle or work” means any machinery, vehicle or work used, employed or performed in an effort to protect, provide or restore safe conditions in the community or for the citizenry, or work by private or public utilities when restoring utility service.
F. “Fixed noise source” means a stationary device which creates sounds while fixed or motionless including, but not limited to, industrial and commercial machinery and equipment, pumps, fans, compressors, generators, air conditioners and refrigeration equipment.
G. “Grading” means any excavating or filling of earth materials, or any combination thereof, conducted at a site to prepare said site for construction or other improvements thereon.
H. “Impact noise” means the noise produced by the collision of one mass in motion with a second mass which may be either in motion or at rest.
I. “Mobile noise source” means any noise source other than a fixed noise source.
J. “Noise level” means the “A” weighted sound pressure level in decibels obtained by using a sound level meter at slow response with a reference pressure of twenty micronewtons per square meter. The unit of measurement shall be designated as dB(A).
K. “Noise variance board” means an administrative board of five members appointed by the board of supervisors of the county, per Title 4, Division 6, Article 1 of the codified ordinances of the county.
L. “Person” means a person, firm, association, copartnership, joint venture, corporation or any entity, public or private in nature.
M. “Residential property” means a parcel of real property which is developed and used either in part or in whole for residential purposes, other than transient uses such as hotels and motels.
N. “Simple tone noise” means a noise characterized by a predominant frequency or frequencies so that other frequencies cannot be readily distinguished.
O. “Sound level meter” means an instrument meeting American National Standard Institute’s Standard S1.4-1971 for Type 1 or Type 2 sound level meters or an instrument and the associated recording and analyzing equipment which will provide equivalent data.
P. “Sound pressure level” of a sound, in decibels, shall mean twenty times the logarithm to the base ten of the ratio of the pressure of the sound to a reference pressure, which reference pressure shall be explicitly stated. (Prior code § 9.44.020) 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
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9.28.025 Excessively loud events.
City or law enforcement personnel who receive a complaint related to excessively loud, unusual, penetrating, or boisterous noise, disturbance, or commotion shall handle the matter in accordance with the provisions of this chapter and Chapter 9.30 of this title. (Ord. 1021 § 2, 2013; Ord. 838 § 1, 2000)
9.28.030 Noise level measurement criteria.
Any noise level measurements made pursuant to the provisions of this chapter shall be performed using a sound level meter as defined in Section 9.28.020. (Prior code § 9.44.030)
9.28.040 Designated noise zone.
The residential properties hereinafter described are hereby assigned to the following noise zones:
Noise Zone 1: all residential properties, whether incorporated or unincorporated. (Prior code § 9.44.040)
9.28.050 Exterior noise standards.
A. The following noise standards, unless otherwise specifically indicated, shall apply to all residential property within a designated noise zone:
Noise Standards
Noise Zone Noise Level Time Period
1 55 dB(A) 7:00 a.m. - 10:00 p.m.
50 dB(A) 10:00 p.m. - 7:00 a.m.
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https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 5/11 In the event the alleged offensive noise consists of impact noise, simple tone noise, speech, music, or any combination thereof, each of the above noise levels shall be reduced by five dB(A).
B. It is unlawful for any person at any location within the incorporated area of the city to create any noise, or to allow the creation of any noise on property owned, leased, occupied, or otherwise controlled by such person, when the foregoing causes the noise level, when measured on any other residential property, either incorporated or unincorporated, to exceed:
1. The noise standard for a cumulative period of more than thirty minutes in any hour; or
2. The noise standard plus five dB(A) for a cumulative period of more than fifteen minutes in any hour; or
3. The noise standard plus ten dB(A) for a cumulative period of more than five minutes in any hour; or
4. The noise standard plus fifteen dB(A) for a cumulative period of more than one minute in any hour; or
5. The noise standard plus twenty dB(A) for any period of time.
C. In the event the ambient noise level exceeds any of the first four noise limit categories above, the cumulative period applicable to said category shall be increased to reflect said ambient noise level. In the event the ambient noise level exceeds the fifth noise limit category, the maximum allowable noise level under said category shall be increased to reflect the maximum ambient noise level. (Prior code § 9.44.050)
9.28.060 Interior noise standards.
A. The following interior noise standards, unless otherwise specifically indicated, shall apply to all residential property within a designated noise zone:
Interior Noise Standards
Noise Zone Noise Level Time Period
1 55 dB(A) 7:00 a.m. - 10:00 p.m.
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In the event the alleged offensive noise consists of impact noise, simple tone noise, speech, music, or any combination thereof, each of the above noise levels shall be reduced by five dB(A).
B. It is unlawful for any person at any location within the incorporated area of the city to create any noise, or to allow the creation of any noise on property owned, leased, occupied, or otherwise controlled by such person, when the foregoing causes the noise level when measured within any other dwelling unit on any residential property, either incorporated or unincorporated, to exceed:
1. The interior noise standard for a cumulative period of more than five minutes in any hour; or
2. The interior noise standard plus five dB(A) for a cumulative period of more than one minute in any hour; or
3. The interior noise standard plus ten dB(A) for any period of time.
C. In the event the ambient noise level exceeds either of the first two noise limit categories above, the cumulative period applicable to said category shall be increased to reflect said ambient noise level. In the event the ambient noise level exceeds the third noise limit category, the maximum allowable noise level under said category shall be increased to reflect the maximum ambient noise level. (Prior code § 9.44.060)
9.28.070 Special provisions.
The following activities shall be exempted from the provisions of this chapter:
A. Activities conducted on the grounds of any public or private nursery, elementary, intermediate or secondary school or college; B. Outdoor gatherings, public dances, shows and sporting and entertainment events provided said events are conducted pursuant to a permit issued by the city pursuant to the city code relative to the staging of said events; C. Activities conducted on any park or playground provided such park or playground is owned and operated by a public entity; D. Any mechanical device, apparatus or equipment used, related to or connected with emergency machinery, vehicle or work; 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 7/11 E. Noise sources associated with construction, repair, remodeling, or grading of any real property provided said activities do not take place between the hours of eight p.m. and seven a.m. on weekdays, including Saturday, or at any time on Sunday or a federal holiday; F. All mechanical devices, apparatus or equipment which are utilized for the protection or salvage of agricultural crops during periods of potential or actual frost damage or other adverse weather conditions; G. Mobile noise sources associated with agricultural operations provided such operations do not take place between the hours of eight p.m. and seven a.m. on weekdays, including Saturday, or at any time on Sunday or a federal holiday; H. Mobile noise sources associated with agricultural pest control through pesticide application; provided, that the application is made in accordance with restricted material permits issued by or regulations enforced by the agricultural commission; I. Noise sources associated with the maintenance of real property provided said activities take place between the hours of seven a.m. and eight p.m. on any day except Sunday or federal holiday, or between the hours of nine a.m. and eight p.m. on Sunday or federal holiday; J. Any activity to the extent regulation thereof has been preempted by state or federal law; K. Any event or activity sponsored by the city. (Ord. 1021 § 3, 2013; prior code § 9.44.070)
9.28.080 Schools, hospitals and churches— Special provisions.
It is unlawful for any person to create any noise which causes the noise level at any school, hospital or church, while the same is in use, to exceed the noise limits as specified in Section 9.28.050 prescribed for the assigned noise zone in which the school, hospital or church is located, or which noise level unreasonably interferes with the use of such institutions or which unreasonably disturbs or annoys patients in the hospital, provided conspicuous signs are displayed in three separate locations within one-tenth of a mile of the institution indicating the presence of a school, church, or hospital. (Prior code § 9.44.080)
9.28.090 Air conditioning and refrigeration—Special provisions.
Until January 19, 1979, the noise standards enumerated in Sections 9.28.050 and 9.28.060 shall be increased eight dB(A) where the alleged offensive noise source is an air conditioning or refrigeration system or associated equipment which was installed prior to the effective date of the ordinance codified in this chapter. (Prior code § 9.44.090)
9.28.095 Special noise sources—Radios, television sets and similar devices. 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 8/11 A. Use Restricted. It is unlawful and a misdemeanor, subject to punishment in accordance with Chapter 1.10 of this code, for any person within the city of Stanton to use or operate any radio receiving set, musical instrument, phonograph, television set, or other machine or device for the producing or reproducing of sound at any time in such a manner as to produce noise levels on residential land which would disturb the peace, quiet, and comfort of neighboring residents or any reasonable person of normal sensitivity residing in the area.
B. Prima Facie Violation. Any noise exceeding the ambient noise level at the property line of any residential area (or if a condominium or apartment house, within any adjoining apartment) by more than five decibels shall be deemed to be prima facie evidence of a violation of the provisions of this section. (Ord. 838 § 2, 2000)
9.28.096 Same—Machinery, fans and other mechanical devices.
Any noise level from the use or operation of any machinery, equipment, pump, fan, air conditioning apparatus, refrigerating equipment, or other mechanical or electrical device, or in repairing or rebuilding any motor vehicle, which exceeds the noise limits as set forth in this title at any property line, or, if a condominium or rental unit, within any condominium unit or rental unit within the complex, shall be a violation of this chapter. (Ord. 838 § 3, 2000)
9.28.100 Noise level measurement.
The location selected for measuring exterior noise levels shall be at any point on the affected property. Interior noise measurements shall be made within the affected dwelling unit. The measurement shall be made at a point at least four feet from the wall, ceiling, or floor nearest the alleged offensive noise source and may be made with the windows of the affected unit open. (Prior code § 9.44.100)
9.28.110 Manner of enforcement.
A. The county health officer and duly authorized representatives are directed to enforce the provisions of this chapter. The county health officer and duly authorized representatives are authorized, pursuant to Penal Code Section 836.5, to arrest any person without a warrant when they have reasonable cause to believe that such person has committed a misdemeanor in their presence.
B. No person shall interfere with, oppose or resist any authorized person charged with enforcement of this chapter while such person is engaged in the performance of his or her duty. (Prior code § 9.44.110)
9.28.120 Variance procedure.
11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 9/11 A. The owner or operator of a noise source which violates any of the provisions of this chapter may file an application with the health officer for a variance from the provisions of this chapter wherein said owner or operator shall set forth all actions taken to comply with said provisions, the reasons why immediate compliance cannot be achieved, a proposed method of achieving compliance, and a proposed time schedule for its accomplishment. Said application shall be accompanied by a fee in the amount of seventy-five dollars. A separate application shall be filed for each noise source; provided, however, that several mobile sources under common ownership, or several fixed sources on a single property may be combined into one application. Upon receipt of said application and fee, the health officer shall refer it with his or her recommendation thereon within thirty days to the noise variance board for action thereon in accordance with the provisions of this chapter.
B. An applicant for a variance shall remain subject to prosecution under the terms of this chapter until a variance is granted. (Prior code § 9.44.120)
9.28.130 Noise variance board.
The noise variance board shall evaluate all applications for variance from the requirements of this chapter and may grant said variances with respect to time for compliance, subject to such terms, conditions and requirements as it may deem reasonable to achieve maximum compliance with the provisions of this chapter. Said terms, conditions and requirements may include, but shall not be limited to, limitations on noise levels and operating hours. Each such variance shall set forth in detail the approved method of achieving maximum compliance and a time schedule for its accomplishment. In its determinations the board shall consider the magnitude of nuisance caused by the offensive noise; the uses of property within the area of impingement by the noise; the time factors related to study, design, financing and construction of remedial work; the economic factors related to age and useful life of equipment; and the general public interest and welfare. Any variance granted by the board shall be by resolution and shall be transmitted to the health officer for enforcement. Any violation of the terms of the variance shall be unlawful. (Prior code § 9.44.130)
9.28.140 Appeals.
A. Within fifteen days following the decision of the variance board on an application, the applicant, the health officer or any member of the city council may appeal the decision to the city council by filing a notice of appeal with the secretary of the variance board. In the case of an appeal by the applicant for a variance, the notice of appeal shall be accompanied by a fee to be computed by the secretary on the basis of the estimated cost of preparing the materials required to be forwarded to the city council as discussed in this section. If the actual cost of such preparation differs from the estimated cost appropriate payments shall be made either to or by the secretary. 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 10/11 B. Within fifteen days following receipt of a notice of appeal fee, the secretary of the variance board shall forward to the city council copies of the application for variance; the recommendation of the health officer; the notice of appeal; all evidence concerning said application received by the variance board and its decision thereon. In addition, any person may file with the city council written arguments supporting or attaching said decision and the city council may in its discretion hear oral arguments thereon. The city clerk shall mail to the applicant a notice of the date set for hearing of the appeal. The notice shall be mailed at least ten days prior to the hearing date.
C. Within sixty days following its receipt of the notice of the appeal, the city council shall either affirm, modify or reverse the decision of the variance board. Such decision shall be based upon the city council’s evaluation of the matters submitted to the city council in light of the powers conferred on the variance board and the factors to be considered both as enumerated in Sections 9.28.120 and 9.28.130.
D. As part of its decision the council may direct the variance board to conduct further proceedings on said application. Failure of the city council to affirm, modify or reverse the decision of the variance board within said sixty-day period shall constitute an affirmance of the decision. (Prior code § 9.44.140)
9.28.150 Violation—Misdemeanor.
A. It is unlawful for any person to violate any provision or to fail to comply with any of the requirements of this chapter.
B. Any person violating any provision hereof shall be charged in accordance with Section 1.04.080 of this code and upon conviction shall be punished in accordance therewith.
C. The provisions of this chapter shall not limit any other remedies authorized by law. (Ord. 1021 § 4, 2013; Ord. 677 § 1, 1988: prior code § 9.44.150)
Contact:
City Clerk: 714-379-9222
Published by Quality Code Publishing, Seattle, WA. By using this site, you agree to the terms of use. 11/14/22, 9:38 AM Chapter 9.28 NOISE CONTROL
https://library.qcode.us/lib/stanton_ca/pub/municipal_code/item/title_9-chapter_9_28?view=all 11/11 CONSTRUCTION NOISE MODELING
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/11/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Architectural Coating Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Compressor (air) No 40 77.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Compressor (air) 77.7 73.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 77.7 73.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/11/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Building Construction Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Front End Loader No 40 79.1 50.0 0.0
Tractor No 40 84.0 50.0 0.0
Generator No 50 80.6 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Front End Loader 79.1 75.1 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Generator 80.6 77.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 84.0 82.8 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/08/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Demolition Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Concrete Saw No 20 89.6 50.0 0.0
Excavator No 40 80.7 50.0 0.0
Dozer No 40 81.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Concrete Saw 89.6 82.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Excavator 80.7 76.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Dozer 81.7 77.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 89.6 84.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/08/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Fine Grading Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Tractor No 40 84.0 50.0 0.0
Grader No 40 85.0 50.0 0.0
Dozer No 40 81.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Grader 85.0 81.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Dozer 81.7 77.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 85.0 84.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/11/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Finish and Landscaping Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Excavator No 40 80.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Excavator 80.7 76.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 80.7 76.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/11/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Paving Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Concrete Mixer Truck No 40 78.8 50.0 0.0
Tractor No 40 84.0 50.0 0.0
Pavement Scarafier No 20 89.5 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Concrete Mixer Truck 78.8 74.8 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A
Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Pavement Scarafier 89.5 82.5 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 89.5 84.9 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/08/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Rough Grading Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Tractor No 40 84.0 50.0 0.0
Grader No 40 85.0 50.0 0.0
Dozer No 40 81.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Grader 85.0 81.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Dozer 81.7 77.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 85.0 84.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/08/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Site Preparation Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Roller No 20 80.0 50.0 0.0
Tractor No 40 84.0 50.0 0.0
Dozer No 40 81.7 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Roller 80.0 73.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Dozer 81.7 77.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 84.0 82.5 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Roadway Construction Noise Model (RCNM),Version 1.1
Report date: 12/11/2023
Case Description: PBK-01
**** Receptor #1 ****
Baselines (dBA)
Description Land Use Daytime Evening Night
----------- -------- ------- ------- -----
Utilities Trenching Residential 60.0 55.0 50.0
Equipment
---------
Spec Actual Receptor Estimated
Impact Usage Lmax Lmax Distance Shielding
Description Device (%) (dBA) (dBA) (feet) (dBA)
----------- ------ ----- ----- ----- -------- --------- Excavator No 40 80.7 50.0 0.0
Tractor No 40 84.0 50.0 0.0
Pickup Truck No 40 75.0 50.0 0.0
Results
-------
Noise Limits (dBA) Noise Limit Exceedance (dBA)
---------------------------------------------- ---------------------------------------------- Calculated (dBA) Day Evening Night Day Evening Night
---------------- -------------- ------------- -------------- -------------- -------------- -------------- Equipment Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq Lmax Leq
---------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ ------ Excavator 80.7 76.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tractor 84.0 80.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Pickup Truck 75.0 71.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Total 84.0 82.0 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
PBK-01 - Construction Noise Modeling Attenuation Calculations Levels in dBA Leq
Phase
RCNM
Reference
Noise Level
Residence at
35 Juniper
Court
Jade Palace
Motel to the
east at 11231
Beach
Boulevard
Residence at 7872
Ruthann Avenue
Residence
at 11205
Mario Lane
Distance in feet 50 710 260 225 540
Demolition 85 62 71 72 64
Site Prep 83 60 69 70 62
Grading 85 62 71 72 64
Distance in feet 50 470 420 350 510
Building Construction 83 64 65 66 63
Architectural Coating 74 55 56 57 54
Distance in feet 50 570 410 320 500
Paving 85 64 67 69 65
Distance in feet 50 710 260 225 540
Finish/Landscaping 77 54 63 64 56
Utilities Trenching 82 59 68 69 61
Attenuation calculated through Inverse Square Law: Lp(R2) = Lp(R1) - 20Log(R2/R1) PBK-01 - Vibration Damage Attenuation Calculations
Levels, PPV (in/sec)
Commercial
Building to the
North
Commercial Building
to the East
Residence to the
South
Instituitional
Building to the West
Distance in feet 50 10 30 50
Vibratory Roller 0.21 0.074 0.830 0.160 0.074
Static Roller 0.05 0.018 0.198 0.038 0.018
Large Bulldozer 0.089 0.031 0.352 0.068 0.031
Loaded Trucks 0.076 0.027 0.300 0.058 0.027
Jackhammer 0.035 0.012 0.138 0.027 0.012
Small Bulldozer 0.003 0.001 0.012 0.002 0.001
Vibration
Reference Level
at 25 feet
PBK-01 - Vibration Annoyance Attenuation Calculations
Levels in VdB
Equipment
Residence to the
South
Distance in feet 240
Vibratory Roller 94.0 64.5
Static Roller 87.0 57.5
Large Bulldozer 87.0 57.5
Loaded Trucks 86.0 56.5
Jackhammer 79.0 49.5
Small Bulldozer 58.0 28.5
Vibration @ 25
ft
PBK-01 - Stationary Noise Attenuation Calculations
Softball/Baseball Basketball
Reference Distance in feet 72 20
Reference Levels, dBA Leq 57 60
Distance and Direction to 90 feet South 330 feet South
Distance Only 90 330
Levels in dBA Leq
Softball/Baseball Basketball
Attenuated Levels at Receptors 55 35
Normalized Levels and Distances
Softball/Baseball Basketball
56.9 59.5
Reference Distance 72 20
Normalized Distance 90 330
Normalized Level dBA Leq 55 35
Attenuation calculated through Inverse Square Law: Lp(R2) = Lp(R1) - 20Log(R Reference Levels, Distances, and
Receptor (residences) Distances
Attenuated Noise Levels
TRAFFIC NOISE MODELING
ID Leq-24hr Ldn CNEL 70 dBA 65 dBA 60 dBA Roadway Segment ADT Posted Speed Limit
Grade % Autos % Med
Trucks
% Heavy
Trucks % Daytime % Evening % Night Number of Lanes
Site
Condition
Distance to
Reciever
2 77.2 80.9 81.3 283 610 1315 SR-39 South of Katella Avenue 64,600 65 0.0% 97.5% 1.6% 0.9% 75.0% 10.0% 15.0% 6 Soft 50 Traffic Noise Calculator: FHWA 77-108 Project Title: PBK-01 Existing Traffic. dBA at 50 feet Distance to CNEL Contour
Output Inputs
PBK‐01
Traffic Noise Calculations
Roadway Segment
Existing NoProject
Existing Plus
Project
Future No
Project
Future PlusProject
Project
NoiseIncrease
CumulativeIncrease
Project
CumulativeContribution
Beach Boulevard ‐ North of Katella Avenue 66,000 66,104 66,700 66,804 0.01 0.05 0.01 Beach Boulevard ‐ South of Katella Avenue to Park Exi 66,000 66,208 66,700 66,908 0.01 0.06 0.01 Beach Boulevard ‐ South of Park Exit to U‐turn 66,000 66,415 66,700 67,115 0.03 0.07 0.03 Beach Boulevard ‐ North of Orangewood Avenue 66,000 66,104 66,700 66,804 0.01 0.05 0.01 Katella Avenue ‐ West of Cedar Street 31,200 31,304 31,500 31,604 0.01 0.06 0.01 Katella Avenue ‐ Cedar Street to Beach Boulevard 31,200 31,408 31,500 31,708 0.03 0.07 0.03 Katella Avenue ‐ East of Beach Boulevard 25,000 25,104 31,500 31,604 0.02 1.02 0.01 ADT Volumes dBA CNEL Increase
N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
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N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
February 2025
Appendix F Traffic/Transportation Analysis
TRAFFIC/TRANSPORTATION ANALYSIS
FOR THE PROPOSED
NORM ROSS SPORTS PARK IMPROVEMENT PROJECT
STANTON
Prepared for
CITY OF STANTON
Prepared by
GARLAND ASSOCIATES 16787
Beach Boulevard, Suite 234
Huntington Beach, CA 92647
714-330-8984
December 2023
i
TABLE OF CONTENTS
Page
I. Project Description and Study Methodology 1
II. Baseline Conditions/Environmental Setting 2
Street Network, Sidewalks, and Crosswalks 2
Bike Lanes 3
Public Transportation 3
III. Traffic/Transportation Environmental Analysis 4
IV. Summary of Impacts and Conclusions 9
FIGURES
ii
LIST OF TABLES
Page
1. Intersections Near the Park Site 3
2. Project Generated Traffic 5
3. Project Impacts on Daily Traffic Volumes 6
LIST OF FIGURES
(AT END OF REPORT)
1. Location Map
2. Site Plan
1 I.
PROJECT DESCRIPTION AND STUDY METHODOLOGY
This traffic/transportation analysis was conducted to determine the impacts of the proposed Norm Ross Sports Park Improvement Project in Stanton. The project site is west of Beach Boulevard and south of Katella Avenue, as shown on Figure 1. It is bounded by the Stanton Storm Channel and Stanton Park on the north, commercial uses with frontage on Beach Boulevard on the east, residences with frontage on Ruthann Avenue on the south, and Carver Early Childhood Education Center on the west. The proposed site plan for the sports park is shown on Figure 2.
The proposed project includes a little league baseball field, a soccer field, a multipurpose sports court, a playground, a courtyard, a picnic area, a community garden, a dog park, and a park building with restrooms. Pedestrian access to the sports park would be provided by pedestrian bridges across the Stanton Storm Channel, two of which are existing and one of which would be constructed as a component of the project. Parking would be provided at an existing parking lot that is positioned along the north side of Stanton Park. It is accessed from Katella Avenue via Cedar Street and it has an exit-only driveway onto Beach Boulevard.
The objective of the analysis is to evaluate the traffic/transportation impacts of the proposed project. The methodology for the traffic study, in general, was to l) describe the baseline conditions on the streets and other transportation facilities that provide access to the project site to establish the environmental setting, and 2) present an evaluation of the project’s impacts on the four transportation issue areas cited in the CEQA environmental checklist. Appendix G of the CEQA Guidelines states that a proposed project could have a significant effect on the environment if the project would:
a. Conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities, b. Conflict or be inconsistent with CEQA Guidelines § 15064.3, subdivision (b), c. Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment), d. Result in inadequate emergency access.
Item “b” involves an evaluation of the project’s impacts on vehicle miles traveled (VMT). To establish the baseline conditions, an inventory was taken of the streets, sidewalks, bike lanes, and transit routes in the vicinity of the park site.
2 II.
BASELINE CONDITIONS/ENVIRONMENTAL SETTING
The following paragraphs provide a brief description of the streets that provide access to the park site, the existing bicycle and pedestrian facilities, and the existing transit service in the area.
Street Network, Sidewalks, and Crosswalks
The streets that provide access to the park site include Katella Avenue, Beach Boulevard, Cedar Street, and Ruthann Avenue. The following paragraphs provide a brief description of the characteristics of these streets.
Katella Avenue
Katella Avenue is a six lane east-west arterial street located approximately 800 feet north of the park site. It has sidewalks on both sides of the street and parking is prohibited on both sides of the street in the vicinity of the project site. Katella Avenue is a divided highway with raised medians.
Access to the park site is provided from Katella Avenue via Cedar Street. The speed limit on Katella Avenue is 45 miles per hour (mph).
Beach Boulevard/State Route 39
Beach Boulevard/State Route 39 is an eight lane north-south arterial street located approximately 200 feet east of the park site. It has sidewalks on both sides of the street and parking is prohibited on both sides of the street in the vicinity of the project site. Beach Boulevard is a divided highway with raised medians. Egress from the parking lot on the north side of the park site is provided on Beach Boulevard. The speed limit on Beach Boulevard is 45 mph.
Cedar Street
Cedar Street is a two lane north-south street that provides a link between Katella Avenue and the parking lot on the north side of the project site. It has sidewalks on both sides of the street and parking is provided on the west side of the street. The speed limit on Cedar Street is 25 mph.
Ruthann Avenue
Ruthann Avenue is a two lane east-west local residential street located approximately 60 feet south of the park site. It has sidewalks and parking on both sides of the street. A gated emergency access driveway is provided from Ruthann Avenue to the park on the southeast corner of the project site.
The speed limit on Ruthann Avenue is 25 mph.
Intersections Near the Park Site
The intersections that are near the park site and the types of traffic control at each intersection are shown in Table 1. The locations of the existing crosswalks are also shown. The crosswalks at the signalized intersections are equipped with pedestrian push buttons and pedestrian WALK signals. 3 TABLE 1
INTERSECTIONS NEAR THE PARK SITE
Intersection Traffic Control Crosswalks
Beach Boulevard at Katella Avenue Traffic Signal On All Four Sides Katella Avenue at Rose Street Traffic Signal On North & East Sides Katella Avenue at Cedar Street Traffic Signal On East & South Sides Cedar Street at Parking Garage North Driveway 3-Way Stop Signs On South and West Sides Cedar Street at Parking Garage South Driveway Stop Sign at Driveway Exit On West Side at Driveway Bike Lanes
There are no marked bike lanes on the streets in the immediate vicinity of the park site. Bike racks are provided at the Stanton City Hall on the west side of Cedar Street and at the Stanton Branch of the Orange County Library on the east side of Cedar Street.
Public Transportation
Orange County Transportation Authority (OCTA) operates Routes 29, 29A, and 529 on Beach Boulevard. Routes 29 and 29A run from Huntington Beach to La Habra. Route 529 is a weekdayonly express bus that runs from Huntington Beach to Fullerton. These bus routes have northbound and southbound bus stops at Katella Avenue. OCTA also operates Route 50 on Katella Avenue. It runs from Long Beach to Orange and has eastbound and westbound bus stops at Beach Boulevard and Cedar Street. These bus routes offer a convenient public transportation option for patrons of the park.
4 III.
TRAFFIC/TRANSPORTATION ENVIRONMENTAL ANALYSIS
For the transportation analysis, Appendix G of the CEQA Guidelines states that a proposed project could have a significant effect on the environment if the project would:
Environmental Issues
Potentially
Significant
Impact
Less Than
Significant
With
Mitigation
Incorporated
Less Than
Significant
Impact
No
Impact
a) Conflict with a program, plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities?
X
b) Conflict or be inconsistent with CEQA Guidelines § 15064.3, subdivision (b)? X
c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?
X
d) Result in inadequate emergency access? X
The table indicates that the project would have a less than significant impact for two environmental issue areas and no impact for the other two environmental issue areas for the transportation category. Details regarding these findings are provided below. a) Conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities? Less Than Significant Impact. The following paragraphs summarize the analysis of the project's impacts on the study area traffic/transportation system and facilities. First is a discussion of project generated traffic volumes and the increases in traffic that would occur on the most-directly affected arterial streets. This is followed by an analysis of the impacts of the proposed project on bicycle and pedestrian facilities and public transportation.
Project Generated Traffic
The volumes of traffic expected to be generated by the proposed sports park were determined in order to estimate the impacts of the project on the study area streets. Table 2 shows the estimated volumes of project generated traffic for the morning and afternoon peak hours and for an entire day. The trip generation rates for the park are from the Institute of Transportation Engineers Trip Generation Manual (11th Edition, 2021). The trip rates for the little league games are based on the assumption that each team will have 15 players and two coaches and that each of them will travel to and from the sports park in a single vehicle (with players driven by parents). It is highly likely that there would be multiple players traveling in many of the vehicles, which would reduce the traffic volumes shown in the table. The numbers shown in the table, therefore, represent a worstcase scenario.
Table 2 shows the anticipated traffic volumes for three scenarios: a weekday during non-summer times of the year when there would be two little league games on a given day, a weekday during the summer months when there would be four games per day, and a Saturday when there would be five games per day.
5 TABLE 2
PROJECT GENERATED TRAFFIC
Land Use AM Peak Hour PM Peak Hour Daily
Total In Out Total In Out Traffic
TRIP GENERATION RATES
Public Park (trips per acre) 4.50 59% 41% 3.50 55% 45% 34.0 Little League Baseball (trips
per player and coach per game) 0 0 0 2 1 1 2
GENERATED TRAFFIC VOLUMES
Public Park – 4.2 acres 19 11 8 15 8 7 143
Baseball – Weekday NonSummer (2 games, 15 players
& 2 coaches per team = 60
players & 8 coaches per day)
0 0 0 68 34 34 136
Baseball – Weekday Summer
(4 games, 15 players & 2
coaches per team = 120
players & 16 coaches per day)
0 0 0 68 34 34 272
Baseball – Saturday (5 games,
15 players & 2 coaches per
team = 150 players & 20
coaches per day)
0 0 0 68 34 34 340
TOTAL – Park + Baseball
Weekday Non-Summer
Weekday Summer
Saturday
19 19
19 11
11 11
8 8
8 83
83 83
42 42
42 41
41 41
279
415
483
NOTE: The trip generation rates for little league baseball are based on the worst-case assumption that each player will be driven to the park in a separate vehicle by parents. The PM peak hour traffic volumes for the baseball games involves two teams arriving and two teams departing during the one-hour period.
Table 2 indicates that the public park (exclusive of the baseball games) would generate an estimated 19 vehicle trips during the morning peak hour (11 inbound and 8 outbound), 15 trips during the afternoon peak hour (8 inbound and 7 outbound), and approximately 143 vehicle trips per day. On weekdays when little league baseball games would occur, the project site would generate an estimated 83 trips during the afternoon peak hour (42 inbound and 41 outbound). This level of site generated traffic is applicable to non-summer and summer times of year as well as Saturdays. The morning peak hour would remain unchanged and would only involve park traffic because little league games would not occur at that time of day. Table 2 indicates that the proposed project would generate 279 daily trips on non-summer weekdays, 415 daily trips on a summer weekday, and 483 daily trips on a Saturday.
It should be noted that the traffic volumes shown in Table 2 do not necessarily introduce new traffic to the overall roadway network but instead represent the traffic that would be re-directed to the proposed park site from other existing parks, because the little league games would most likely be taking place at other locations in the Stanton area. Most of the baseball-related traffic would be 6 traveling on the roadway network regardless of the status of the proposed project. It has been assumed for the traffic analysis, however, that the additional site-generated traffic would be new traffic on the roadway network.
Impacts on Traffic Volumes
To quantify the increases in traffic volumes on each of the most-directly affected arterial streets resulting from the proposed project, the project generated traffic was geographically distributed onto the street network using directional percentages that are based on the layout of the street network, the existing traffic patterns, and the anticipated geographical distribution of the patrons of the park facilities.
Table 3 shows the existing and projected daily traffic volumes on various segments of Beach Boulevard and Katella Avenue. The table shows the existing traffic volume, the anticipated volume of project generated traffic, the “existing plus project” traffic volume, the projected future traffic volume for the year 2024 (without the project), and the “future with project” traffic volume for each street segment.
TABLE 3
PROJECT IMPACTS ON DAILY TRAFFIC VOLUMES
Table 3 indicates that the increases in daily traffic volumes generated by the proposed park would be negligible compared to the existing and projected traffic volumes on Beach Boulevard and Katella Avenue. The proposed project would not, therefore, result in a significant adverse impact on traffic volumes.
Bicycle and Pedestrian Facilities
The proposed project would generate an increased demand for non-motorized travel as some park patrons and little league participants would travel to and from the project site as pedestrians or on bicycles. The streets in the vicinity of the park site have sidewalks along both sides of the street and the nearby intersections are equipped with painted crosswalks. The signalized intersections have pedestrian push buttons and pedestrian WALK signals. While there are no bike lanes on the nearby streets, little league players could potentially ride their bikes on the sidewalks of these major arterial routes. Nearby bike racks are available at City Hall and the Stanton Branch of the Orange County Library and bike racks would be provided at the project site. So there are multiple features at and near the project site that can accommodate bicycle and pedestrian travel.
Public Transit
With regard to public transit, some park patrons, little league baseball players, and coaches could potentially use the OCTA buses to travel to and/or from the park site. OCTA operates Routes 29, Street Segment Existing ADT Project Traffic Existing + Project Future ADT (2024) Future with Project Beach Boulevard
North of Katella Avenue 66,000 104 66,104 66,700 66,804 South of Katella Avenue to Park Exit 66,000 208 66,208 66,700 66,908 South of Park Exit to U-Turn 66,000 415 66,415 66,700 67,115 North of Orangewood Avenue 66,000 104 66,104 66,700 66,804 Katella Avenue
West of Cedar Street 31,200 104 31,304 31,500 31,604
Cedar Street to Beach Boulevard 31,200 208 31,408 31,500 31,708 East of Beach Boulevard 25,000 104 25,104 31,500 31,604 7 29A, and 529 on Beach Boulevard and Route 50 on Katella Avenue in the vicinity of the project site. The project’s impact on the operation and ridership levels on these bus routes would be negligible.
Conclusions
In summary, the proposed project would not adversely affect traffic conditions on the study area roadway network or the performance of any transit, pedestrian, or bicycle facilities. The project would not conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities and no mitigation measures would be required.
b) Conflict or be inconsistent with CEQA Guidelines § 15064.3, subdivision (b)? Less Than Significant Impact. Vehicle delays and levels of service (LOS) have historically been used as the basis for determining the significance of traffic impacts as standard practice in California Environmental Quality Act (CEQA) documents. On September 27, 2013, SB 743 was signed into law, starting a process that fundamentally changed transportation impact analyses as part of CEQA compliance. SB 743 eliminates auto delay, LOS, and other similar measures of vehicular capacity or traffic congestion as the sole basis for determining significant impacts under CEQA. As part of the new CEQA Guidelines, the new criteria “shall promote the reduction of greenhouse gas emissions, the development of multimodal transportation networks, and a diversity of land uses” (Public Resources Code Section 21099(b)(1)). Pursuant to SB 743, the California Natural Resources Agency adopted revisions to the CEQA Guidelines on December 28, 2018, to implement SB 743. CEQA Guidelines Section 15064.3 describes how transportation impacts are to be analyzed after SB 743. Under the new Guidelines, metrics related to “vehicle miles traveled” (VMT) are required beginning July 1, 2020, to evaluate the significance of transportation impacts under CEQA for development projects, land use plans, and transportation infrastructure projects.
The State provided an “opt-in period” and did not require lead agencies to apply a VMT metric until July 1, 2020. However, in January 2020, State courts stated that under the Public Resources Code Section 21099, subdivision (b)(2), “automobile delay, as described solely by level of service or similar measures of vehicular capacity or traffic congestion shall not be considered a significant impact on the environment” under CEQA, except for roadway capacity projects.
As stated in the Orange County “Transportation Implementation Manual” (County of Orange, September 2021) and the “Guidelines for Evaluating Vehicle Miles Traveled Under CEQA” (County of Orange, September 2020), a project that generates 500 or fewer average daily trips (ADT) may be assumed to result in a less than significant transportation impact and can be screened from a CEQA VMT analysis because it falls into the small project category. As the traffic that would be generated by the proposed project is below the VMT threshold of 500 trips per day, it can be screened from any further CEQA VMT analysis and would not result in a significant impact relative to VMT.
In addition, the Orange County guidelines state that the development of public facilities, which includes institutional/government and public service uses, can be screened from a CEQA VMT 8 analysis. As the proposed sports park project is included in the public facilities category, it can be screened in accordance with the Orange County guidelines. It is concluded, therefore, that the project would have a less than significant VMT impact and no mitigation measures would be required.
c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? No Impact. The proposed project would not provide any on- or off-site access or circulation features that would create or increase any design hazards or incompatible uses. Access to the park site for vehicles, bicyclists, and pedestrians would continue to occur via properly designed streets, driveways, sidewalks, and on-site pedestrian pathways and a new pedestrian bridge would be constructed across the Stanton Storm Channel to improve pedestrian access to the sports park. The streets, intersections, driveways, and on-site circulation system are designed to accommodate the anticipated levels of vehicular and pedestrian activity and have historically been accommodating park-related traffic on a daily basis. These facilities would continue to be compatible with the design and operation of a park.
As the proposed project would not result in any adverse changes to the access or circulation features at the project site or on the surrounding streets, there would be no impacts involving increased hazards due to a geometric design feature or incompatible uses. d) Result in inadequate emergency access?
No Impact. Emergency access will be provided by a gated driveway located at the southeast corner of the sports park site that connects to Ruthann Avenue. In addition, emergency vehicles can access the parking lot on the north side of the project site via Beach Boulevard and Cedar Street. The existing and proposed access and circulation features at the project site would continue to accommodate emergency ingress and egress by fire trucks, police units, and ambulance/paramedic vehicles. The proposed project would not, therefore, result in inadequate emergency access.
Mitigation Measures Applicable to the Proposed Project
No mitigation measures related to transportation would be required of the proposed project. 9 IV.
SUMMARY OF IMPACTS AND CONCLUSIONS
The key findings and conclusions of the traffic/transportation impact analysis are outlined below. • The proposed sports park would generate an estimated 19 vehicle trips during the morning peak hour (11 inbound and 8 outbound), 83 trips during the afternoon peak hour (42 inbound and 41 outbound), and 279 to 483 trips per day, depending on the time of year and the days of the week.
• The levels of traffic generated by the project would not result in a significant impact on the roadway network.
• CEQA threshold of significance “a” asks if the proposed project would conflict with a program, plan, ordinance, or policy addressing the circulation system, including transit, roadway, bicycle, and pedestrian facilities. The analysis indicates that the impact would be less than significant because the proposed project would not adversely affect the performance or safety of any roadway, transit, or non-motorized transportation facilities (pedestrians and bicycles) and would not conflict with any adopted plans, policies, or programs relative to these transportation modes.
• CEQA threshold of significance “b” asks if the proposed project would conflict or be inconsistent with CEQA Guidelines section 15064.3, subdivision (b), which addresses vehicle miles traveled (VMT). The analysis indicates that the impact would be less than significant because the proposed project is a public facility and is classified as a small project because it would generate less than 500 vehicle trips per day. Projects in these categories can be screened from a CEQA VMT analysis according to Orange County guidelines.
• CEQA threshold of significance “c” asks if the proposed project would substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment). The analysis indicates that the existing streets, intersections, and driveways and the existing parking lot are designed to accommodate park-related vehicular and pedestrian activity. The proposed sports park would be compatible with the neighborhood and the proposed project would not result in any major hazards for vehicular traffic, pedestrians, or bicyclists. The proposed project would not, therefore, substantially increase hazards due to a geometric design feature or incompatible uses.
• CEQA threshold of significance “d” asks if the proposed project would result in inadequate emergency access. The existing access and circulation features at the park, including the emergency access driveway on Ruthann Avenue, would readily accommodate access for fire trucks, police units, and ambulance/paramedic vehicles. The proposed project would not result in inadequate emergency access.
FIGURE 1
LOCATION MAP
PROJECT
SITE
FIGURE 2
SITE PLAN
N O R M R O S S S P O R T S P A R K I M P R O V E M E N T P R O J E C T I N I T I A L S T U D Y / M I T I G A T E D N E G A T I V E D E C L A R A T I O N
C I T Y O F S T A N T O N
Appendix
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Mitigation Monitoring and Reporting Program
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MITIGATION MONITORING AND REPORTING
PROGRAM
A lead agency adopting a mitigated negative declaration (MND) under the California Environmental Quality Act (CEQA) must adopt a program for reporting on or monitoring the changes that it has required in the project to mitigate or avoid potentially significant environmental effects.
In compliance with CEQA, Table 1, Mitigation Monitoring and Reporting Checklist, has been prepared for the Norm Ross Sports Park Improvement Project (the Project). This Mitigation Monitoring and Reporting Checklist is intended to provide verification that all applicable mitigation measures relating to environmental impacts that could be significant absent mitigation are monitored and reported.
Monitoring will include: 1) verification that each mitigation measure has been implemented; 2) recordation of the actions taken to implement each mitigation; and 3) retention of records in the Project file.
This Mitigation Monitoring and Reporting Program (MMRP) delineates responsibilities for monitoring the Project, but also allows the City flexibility and discretion in determining how best to monitor implementation. Monitoring procedures will vary according to the type of mitigation measure. Adequate monitoring consists of demonstrating that monitoring procedures took place and that mitigation measures were implemented. If an adopted mitigation measure is not being properly implemented, the designated monitoring personnel shall require corrective actions to ensure adequate implementation.
Minor changes to the MMRP, if required, would be made in accordance with CEQA and would be permitted after further review and approval by the City.
As set forth in the MND, the following environmental issue areas were determined to require mitigation to reduce impacts to a level of less than significant:
• Air Quality;
• Biological Resources;
• Cultural Resources;
• Geological Resources;
• Noise; and
• Tribal Cultural Resources.
With the implementation of the mitigation measures identified in Table 1, Mitigation Monitoring and Reporting Checklist, impacts related to the foregoing environmental issue areas will be mitigated to a level of less than significant.
Attachment: E
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Mitigation Monitoring and Reporting Program
Norm Ross Sports Park Improvement Project
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Table 1
Mitigation Monitoring and Reporting Checklist
Mitigation
Number Mitigation Measure Implementation Responsibility Implementation
Timing
Monitoring
Responsibility
Monitoring
Timing
VERIFICATION OF COMPLIANCE
Initials Date Remarks
AIR QUALITY
AQ-1 The City of Stanton shall specify in the
construction bid that the construction
contractor(s) shall water exposed ground
surfaces and disturbed areas three times per
day during earthmoving activities (i.e., site
preparation, rough grading, and fine grading) to
minimize fugitive dust. Prior to construction, the
construction contractor(s) shall ensure that all
construction plans clearly show the watering
requirement to control fugitive dust.
City of Stanton;
construction
contractor
Prior to and During
Construction
Activities
City of Stanton Prior to and
During
Construction
Activities
BIOLOGICAL RESOURCES
BIO-1 Preconstruction Avian Survey. If project
construction-related activities take place during
the nesting season (February through August),
preconstruction surveys for nesting birds and
raptors (birds of prey) within the existing trees
onsite, which would be removed during
construction, shall be conducted by a qualified
biologist 14 days prior to the commencement of
the tree removal or site grading activities. If any
bird listed under the Migratory Bird Treaty Act is
found to be nesting within the project site or
within the area of construction-related activities,
an adequate protective buffer zone shall be
established by a qualified biologist to protect the
nesting site. This buffer shall be a minimum of
75 feet from the project activities for passerine
birds and a minimum of 200 feet for raptors. The
distance shall be determined by a qualified
biologist based on the site conditions
City of Stanton;
qualified biologist
Prior to and During
Construction
Activities
City of Stanton Prior to and
During
Construction
Activities
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Timing
Monitoring
Responsibility
Monitoring
Timing
VERIFICATION OF COMPLIANCE
Initials Date Remarks
(topography, if the nest is in a line of sight of the
construction, and the sensitivity of the birds
nesting). Additional protective measures shall
include establishment of clearly delineated
exclusion zones
CULTURAL RESOURCES
CUL-1 Prior to issuance of grading permits, a qualified archaeological monitor shall be identified to be
on call during ground-disturbing activities. If
archeological resources are discovered during
excavation and/or construction activities,
construction shall stop within 25 feet of the find,
and the qualified archaeologist shall be
consulted to determine whether the resource
requires further study. The archaeologist shall
make recommendations to the applicant to
protect the discovered resources.
Archaeological resources recovered shall be
provided to the South Central Coast Information
Center (SCCIC) or any other local museum or
repository willing and able to accept and house
the resource to preserve for future scientific
study.
City of Stanton;
qualified
archaeological
monitor
Prior to Issuance
of Grading Permits
City of Stanton During Plan
Review and
GroundDisturbing
Activities
GEOLOGICAL RESOURCES
GEO-1 Prior to construction, the City shall identify a
qualified paleontologist to be on-call. If unique
paleontological resources are discovered during
excavation and/or construction activities,
construction shall stop within 25 feet of the find,
and the qualified paleontologist shall be
consulted to determine whether the resource
requires further study. The paleontologist shall
make recommendations to the City to protect the
discovered resources. Any paleontological
City of Stanton;
qualified
paleontologist
Prior to
Construction;
During
Construction
City of Stanton Prior to
Construction;
During
Construction
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Mitigation
Number Mitigation Measure Implementation Responsibility Implementation
Timing
Monitoring
Responsibility
Monitoring
Timing
VERIFICATION OF COMPLIANCE
Initials Date Remarks
resources recovered shall be provided to the
South-Central Coastal Information Center, Los
Angeles County Natural History Museum, or
repository willing and able to accept and house
the resource to preserve for future scientific
study.
NOISE
N-1 The City and its construction contractor shall
implement the following measures during all
ground-disturbing activities:
Vibratory compaction that is within 10 to 25
feet of any surrounding structure shall be
conducted with the use of a static roller in
lieu of a vibratory roller. At a distance
greater than 25 feet, a vibratory roller would
no longer exceed 0.20 inches per second
(in/sec) peak particle velocity PPV and
would be allowed for use. Therefore, a
static roller shall be used within 25 feet
where levels would be reduced to 0.20
in/sec PPV or less and mitigate vibration
damage.
Paving activities within 10 feet of a structure
shall employ self-compacting pea gravel for
the base and a concrete finish as to not
require vibratory compaction.
Demolition activities within 10 feet of
adjacent structures shall be conducted with
off-road equipment that is limited to 100
City of Stanton;
construction
contractor
During GroundDisturbing and
Construction
Activities
City of Stanton During GroundDisturbing and
Construction
Activities
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Number Mitigation Measure Implementation Responsibility Implementation
Timing
Monitoring
Responsibility
Monitoring
Timing
VERIFICATION OF COMPLIANCE
Initials Date Remarks
horsepower or less and the use of small
dozer/tractor is to be used in lieu of a larger
dozer.
TRIBAL CULTURAL RESOURCES
TCR-1 Retain a Native American Monitor Prior to
Commencement of Ground-Disturbing Activities
A. The City shall retain a Native American
Monitor from or approved by the Gabrieleño
Band of Mission Indians – Kizh Nation. The
monitor shall be retained prior to the
commencement of any “ground-disturbing
activity” for the subject project at all project
locations (i.e., both on-site and any off-site
locations that are included in the project
description/definition and/or required in
connection with the project, such as public
improvement work). “Ground-disturbing
activity” shall include, but is not limited to,
demolition, pavement removal, potholing,
auguring, grubbing, tree removal, boring,
grading, excavation, drilling, and trenching.
B. A copy of the executed monitoring
agreement shall be submitted to the City
prior to the earlier of the commencement of
any ground-disturbing activity, or the
issuance of any permit necessary to
commence a ground-disturbing activity.
City of Stanton;
Qualified Native
American
Monitor
During GroundDisturbing
Activities
City of Stanton During GroundDisturbing
Activities
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C. The monitor will complete daily monitoring
logs that will provide descriptions of the
relevant ground-disturbing activities, the
type of construction activities performed,
locations of ground-disturbing activities, soil
types, cultural-related materials, and any
other facts, conditions, materials, or
discoveries of significance to the Tribe.
Monitor logs will identify and describe any
discovered TCRs, including but not limited
to, Native American cultural and historical
artifacts, remains, places of significance,
etc., (collectively, tribal cultural resources,
or “TCR”), as well as any discovered Native
American (ancestral) human remains and
burial goods. Copies of monitor logs will be
provided to the City upon written request to
the Tribe.
D. On-site tribal monitoring shall conclude
upon the earlier of the following (1) written
confirmation to the Kizh from a designated
point of contact for the City that all grounddisturbing activities and phases that may involve ground-disturbing activities on the
project site or in connection with the project
are complete; or (2) a determination and
written notification by the Kizh to the City
that no future, planned construction activity
and/or development/construction phase at
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the project site possesses the potential to
impact Kizh TCRs.
TCR-2 Unanticipated Discovery of Tribal Cultural
Resources Objects (Non-Funerary/NonCeremonial)
Upon discovery of any TCRs, all construction
activities in the immediate vicinity of the
discovery shall cease (i.e., not less than the
surrounding 50 feet) and shall not resume until
the discovered TCR has been assessed by
the Kizh monitor or Kizh archaeologist. The
Kizh will recover and retain all discovered
TCRs in the form and/or manner the Tribe
deems appropriate, in the Tribe’s sole
discretion, and for any purpose the Tribe
deems appropriate, including for educational,
cultural and/or historic purposes.
TCR-3 Unanticipated Discovery of Human Remains
and Associated Funerary or Ceremonial Objects
A. Native American human remains are
defined in PRC 5097.98 (d)(1) as an
inhumation or cremation, and in any state of
decomposition or skeletal completeness.
Funerary objects, called associated grave
goods in Public Resources Code Section
5097.98, are also to be treated according to
this statute.
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Timing
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Timing
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B. If Native American human remains and/or
grave goods are discovered or recognized
on the project site, then Public Resource
Code 5097.9 as well as Health and Safety
Code Section 7050.5 shall be followed.
C. Human remains and grave/burial goods
shall be treated alike per California Public
Resources Code section 5097.98(d)(1) and
(2).
D. Preservation in place (i.e., avoidance) is the
preferred manner of treatment for
discovered human remains and/or burial
goods.
E. Any discovery of human remains/burial
goods shall be kept confidential to prevent
further disturbance.
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