Cup 2017 117 Mariposa Biomass Ceqa Initial Study Subsequent

County of Mariposa

California Environmental Quality Act Initial Study

Project Title: Mariposa Biomass Project Conditional Use Permit CUP 2017-117

TABLE OF CONTENTS

1.0 PROJECT INFORMATION 1.1 Project Description 1.2 Notable Environmental and/or Regulatory Setting Aesthetics/Visual quality Agriculture/Forestry Air Quality Biological Resources Cultural Resources Geology/Soils Greenhouse Gas Emissions Hazards/Hazardous Waste Materials Hydrology Land Use/Planning Mineral Resources Noise Transportation/Traffic Utilities/Services/Solid Waste

2.0 DETERMINATION

3.0 POTENTIALLY SIGNIFICANT EFFECTS CHECKLIST

4.0 ENVIRONMENTAL IMPACTS

List of Attachments:  Attachment A - Vicinity Map  Attachment B - Site Survey  Attachment C - Site Plan  Attachment D - The Facility Elevation Illustration  Attachment E - The Preliminary Grading Plan  Attachment F - Airport Approach, stamped  Attachment G - Mariposa Tree Mortality Maps and Data  Attachment H- Mariposa Tree Removal Plan  Attachment I - The Air Quality Study  Attachment J - The Biological Study  Attachment K -The Botanical Study

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

 Attachment L - The Cultural Resources Assessment (Confidential-Not included available at the Mariposa Planning Department Upon Request)  Attachment M - The Hydrology Study  Attachment N - The Noise Study  Attachment O - Correspondence from Cal Trans  Attachment P - Traffic Study  Attachment Q - Technology Sludge Assessment  Attachment R - Woody Biomass Feedstock Assessment  Attachment S - Guidelines for Log Storage  Attachment T - Septic easement relocation  Attachment U- Draft letter to adjoining property owners

List of Figures:  Figure 1: Vicinity Map (is also Attachment A)  Figure 2: Facility Elevation (is also Attachment D)  Figure 3: Woodroll Gasification Illustration  Figure 4: Photo of the site  Figure 5: Tree Mortality Flyer  Figure 6: GIS Tree Mortality Image from Cal Fire  Figure 7: Photoshop depiction of facility at site location  Figure 8: Photoshop depiction of facility at site location  Figure 9: AERMOD Grid (Figure 2 within the Air Study)  Figure 10: HARP Impacts (Figure 3 within the Air Study)  Figure 11: Map location of the Project in proximity to the airport.  Figure 12: Linear and Conical Surface Map  Figure 13: Airport Elevation (is also Attachment F)

List of Tables:

 Table A: MCAPCD Significance Thresholds  Table B: Special-Status Plant Species Occurring within 5 miles of Study Area  Table C: Stationary Source Emission Estimates  Table D: Construction Emissions Estimates  Table E: Operational Mobile and Temporary Source Emission Estimates  Table F: MCAPCD Significance Thresholds  Table G: Pile and Burn Emission Factors  Table H: Operational Emissions from proposed Project  Table I: Optimized Feedstock Blend  Table J: Year one Feedstock Procurement Forecast  Table K: Modeling Parameters  Table L: Exposure Pathways  Table M: Mariposa Biomass Health Risk Assessment  Table N: Construction GHG

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

List of Tables Continued:  Table O: Mobile GHG Emissions  Table P: Facility GHG Burden  Table Q: The Translocation of Minerals in Trees  Table R: Wood Ash Composition  Table S: Low Temperature Ash Content of Different Wood Species  Table T: Chemical Composition of Sludge

List of Acronyms:

AB Assembly Bill AERMAP AERMOD Terrain Preprocessor AERMOD Atmospheric Dispersion Modeling System APCD Air Pollution Control District APN Assessor Parcel Number AQMD Air Quality Management District ARB Air Resources Board BAC Bollard and Associates BDT or bdt Bone Dry Tons BioMAT Bioenergy Market Adjusting Tariff CalEEMod California Emissions Estimator Model CALFIRE California Department of Forestry and Fire Protection CAPCOA California Air Pollution Control Officer's Association CARB California Air Resources Board CCAA California Clean Air Act CCR California Code of Regulations CDFG California Department of Fish and Game CDFW California Department of Fish and Wildlife CEC California Energy Commission CEQA California Environmental Quality Act CESA California Endangered Species Act CNDDB California Natural Diversity Database CNPS California Native Plant Society CO Carbon Monoxide CO2 Carbon Dioxide CPUC California Public Utilities Commission CRHR California Register of Historic Places CUP Conditional Use Permit CUPA Unified Program Consolidated dBA A-weighted decibels EIR Environmental Impact Report

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

EPA Environmental Protection Agency EPS Emissions Performance Standard EPIC Electric Program Investment Charge FCAA Federal Clean Air Act FESA Federal Endangered Species Act FHWA Federal Highway Administration FICON Federal Interagency Committee on Noise FIT Feed-In-Tariff FSA Forest Service Area GHG Greenhouse Gas GIS Geographic Information System HARP Hotspots Analysis Reporting Program HCP Habitat Conservation Plan HRA Health Risk Assessment Kw Kilowatt LDA MND Land Division 2004-185 MBP Mariposa Biomass Project MCAPCD Mariposa County Air Pollution Control District MCAPCO Mariposa County Air Pollution Control Officer MCRCD Mariposa County Resource Conservation District MEIR Maximally Exposed Individual Residence MEIW Maximally Exposed Individual Worker MLD Most Likely Descendent MRR Mandatory Reporting Regulation MT Metric Tons MW Megawatts NAAQS National Ambient Air Quality Building Standards NAHC Native American Heritage Commission NCCP Natural Community Conservation Plan NEPA National Environmental Policy Act NO2 Nitrogen Dioxide NOX Nitric Oxide NPS National Park Service NRHP National Register of Historic Places NRCS Natural Resources Conservation District NREL National Renewable Energy Laboratory O3 Ozone OEHHA Office of Environmental Health Hazard Assessment ORC Organic Rankine Cycle Pb Lead PDZ Planned Development Zone 4

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

PG&E Pacific Gas & Electric PM Particulate Matter PMI Point of maximum Impact PPA Power Purchase Agreement PRC Public Resources Code RCNM Roadway Construction Noise Model ROG Reactive Organic Gases RPS Renewable Portfolio Standard SB State Bill SCE Southern California Edison SCR Selective Catalytic Reduction SDG&E San Diego Gas & Electric SO2 Sulfur Dioxide TAC Toxic Air Contaminants THP Timber Harvest Plan TPY Tons Per Year UCMERCED University of California at Merced USDA US Department of Agriculture USFWS US Fish and Wildlife Service VOC Volatile Organic Compounds WFM Wood Waste from Forest Management WHR World Health Report

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

PROJECT INFORMATION:

Project Title: Mariposa Biomass Project Conditional Use Permit CUP No. 2017-117

Lead Agency Name and Address Mariposa County 5100 Bullion Street, P.O Box 2039 Mariposa, CA 95338

Contact Person and Phone Number Jay Johnson Mariposa Biomass Project 5039 Fairgrounds Road Mariposa, CA 95338 (559) 580-5793 [email protected]

Christiana Darlington, Counsel CLERE Inc. 530-305-4433 [email protected]

Project Location Assessor Parcel Numbers: 015-012-066 and 015-012- 067 5673 Copper Leaf Dr. Mariposa, CA 95338 Projected Sections 9, Rancho Las Mariposas Township 5 South, Range 18 East, MDB&M Bear Valley USGS 7.5' Quadrangle map. (120°0'46.679"W 37°30'19.397"N).

Project Sponsor’s Name and Address Mariposa Biomass Project 5039 Fairgrounds Road Mariposa, CA 95338

CEQA Initial Study Preparation: CLERE Inc., Christiana Darlington, Counsel- Draft Submittal 1130 Diablo Court Auburn, CA 95603 530-305-4433 [email protected]

Mariposa County Planning- Review, Amendments Final Preparation Steve Engfer Associate Planner (209) 742-1250 [email protected]

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

1.0 Project Description

The Property The Project is located just southerly of the intersection of Highway 49 North and Gold Leaf Drive at 5673 Copper Leaf Drive, Mariposa. The Project parcels are within the Mariposa Industrial Park that was approved by the County in 1987 through Subdivision, No. 1259 and a Planned Development Zone PDZ 87-1. The PDZ 87-1 (Mariposa Industrial Park) established uncodified zoning that provides the range of allowed industrial uses and prescribes development standards applicable to projects proposed within PDZ 87-1 as is the case for the Mariposa Biomass project. This Initial study takes into account the previous findings that were made when Subdivision No. 1259, the Mariposa Industrial Park Plan and PDZ 87-1 were approved, including the environmental review that was done at the time.

Subsequently some lots within the Mariposa Industrial Park were subdivided. This Project is made up of two of four parcels that that were part of Subdivision No. 2004-185 that was completed and recorded in November of 2007. The project was a 9.74 acre parcel that was subdivided into four parcels and a remainder: (Parcel 1, 1.93 net acres; Parcel 2, 1.40 net acres; Parcel 3, 2.0 net acres; and Parcel 4, 2.0 net acres) and a Remainder of 1.33 net acres. The Mariposa Biomass project parcels are Parcel 3 of the subdivision Assessor Parcel Number APN 012-050-066 and Parcel 4 of the Subdivision APN 012-050-067. (For ease of reference the project parcels are referred to as Parcels 3 and 4 within this initial study.) All of the new Parcels and remainder are located in a Planned Development Zone and are governed by and subject to the PDZ 87-1 standards for development. The previous environmental review done for the land division, hereinafter referred to as LDA MND, has covered many of the potential environmental impacts for the proposed project, which are referenced throughout this Initial Study.

Any and all mitigation measures and conditions of approval that are applicable to the Property through the PDZ 87-1 or the LDA MND are incorporated as part of the project design or are conditions of approval that will be completed as the project progresses towards commercial operation Of the Mariposa Biomass project.

In addition to the PDZ 87-1 zoning, the Project is approximately 1.2 miles from an airport, and is subject to the County’s Airport Overlay District and the two airport plan documents; The 1995 Airport Master Plan and the Mariposa Yosemite Airport Comprehensive Land Use Plan (Airport Plans). Both Airport Plans were taken into consideration throughout the Project development and therefore the project is designed in compliance with the applicable requirements. The development of the parcels can be seen on the Site Survey (Attachment B), Preliminary Grading Plan (Attachment C) and Site Plan (Attachment E).

Project parcel 4 is a previously disturbed site that has a graded building pad and internal access driveway where the proposed Mariposa Biomass facility structures, buildings and employee parking is proposed. Parcel 3 is undeveloped and is proposed for wood ship storage, truck scale, turnaround and internal material transport road..

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Here is a depiction of the vicinity Map, which can be seen in more detail as Figure 1 is also Attachment A.

The Applicant The Mariposa Biomass Project (MBP) is a 501(c) (3) nonprofit corporation established in 2014 with the primary purpose of developing a bioenergy plant in Mariposa County. MBP owns Parcel 4 in the Mariposa Industrial Park and has lease option to purchase Parcel 3. MBP also has an agreement with Cortus Energy, who will build, own and operate the facility. Cortus Energy is a clean technology company based in Sweden. The Advanced Technology Biomass to Energy Gasification Plant The project is a 2.4 MW (net) community based bioenergy facility which would be located in the Mariposa Industrial Park at 5673 Copper Leaf Rd as indicated on the Vicinity Map (Attachment A). The facility will utilize approximately 12,000 bdt (bone dry tons) per year of sustainably harvested forest biomass in a gasification process to produce a syngas. The syngas will be used to fuel two gas engine generators to produce electricity. In addition, the project will include two Organic Rankine Cycle (ORC) heat recovery turbine generators to further increase the power output and make the facility more efficient. Power will be sold to PG&E under the State of

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

California BioMAT program.1 The project intends to enter into a 2-year Power Purchase Agreement (PPA) with the utility. The project’s immediate goal is to help address effects of tree mortality by processing 36 bdt per day of dead and down trees from the High Hazard Zone in Mariposa County. In the long term, the facility will process biomass from forest thinning operations associated with maintenance of fuel breaks. By purchasing woodchips, the facility will help offset the cost of fuel break maintenance and provide an alternative to prescribed burns. Technology and Project Objectives The technology to be implemented is the WoodRoll® process, a 2-state thermochemical biomass-to-energy conversion process. Cortus Energy, who will build, own and operate the facility, has successfully completed bench scale testing and pilot plant testing in their home country of Sweden. Currently, Cortus Energy is moving forward with two commercial scale facilities, one in Japan and one in Sweden. The Mariposa project will be the first Cortus Energy commercial facility in North America. Attachment D is depicted here as Figure 2:

1 See the following websites for more information on the program: https://www.pge.com/en_US/for-our-business- partners/floating-pages/biomat/biomat.page http://cpuc.ca.gov/SB_1122/

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

It is widely known that the biggest challenge facing small-scale bioenergy projects is financial viability. Scaling down of wood-fired, conventional steam plants has not proven viable for several reasons including poor efficiency, high capital cost per kW and high labor cost per kW. MBP believes the WoodRoll process developed by Cortus Energy which produces a clean syngas gas in conjunction with a high degree of automation, is the solution. The goal of this project is to demonstrate, deploy, and optimize a forest bioenergy technology and assess the performance characteristics and best practices of Wood Waste from Forest Management (WFM) feedstock. Project objectives are to:

● Successfully implement one of California’s first small-scale WFM bioenergy facility producing 2.4 MW (net) of renewable energy from forest biomass ● Reduce operational costs by using an indirect heating process to produce a cleaner syngas thus reducing engine maintenance costs and unscheduled outages ● Reduce fuel costs by demonstrating heat rates in the 12,000 Btu/kW hr range. ● Increase operating revenue by demonstrating capacity factors in excess of 90% ● Reduce operating staff by automation and remote monitoring ● Reduce greenhouse gas and particulate emissions by diverting biomass from burn piles and controlled burns and utilizing the biomass as an energy resource in a controlled environment ● Extract biochar to be tested for suitability as a substitute for activated carbon used in water treatment facilities. Biochar activation is to be accomplished at UC Merced and in situ testing is to be done at the Mariposa Water Treatment Plant

Figure 3

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

In terms of feedstock storage, Parcel 3 will be graded in accordance with the Preliminary Grading Plan (Attachment E) to create a level space on which to store wood chips. Wood chip storage is governed by the 2013 edition of the California Fire Code, Chapter 28. The code limits the height, width and length of the piles as well as pile separation and fire truck access. Conditions will be applied to the Project to ensure compliance with all Fire Code requirements. For example, the project intends to limit the pile height to 15 ft, which results in approximately 24 days of storage. The project will implement a first in first out strategy to simplify the material handling process. Additional storage will be provided “in field”, where the material is collected and processed. The project is also investigating the possibility of purchasing woodchips from the landfill to supplement the county’s need to divert more waste material away from the landfill in response to California’s 75% diversion goal. The County is also faced with the future possibility of having to close the landfill and haul garbage to another location such as Merced. The bioenergy project can utilize up to 2,400 dry tons per year of non-forest wood waste such as residential green waste that has been determined to be clean of any hazardous materials. Potentially this green waste could be collected in Merced and back hauled to Mariposa and sold to the bioenergy facility. Should the County go forward with the compost operation at the landfill, the project has been advised that the compost process needs approximately 1 ton per day of clean, reliably produced ash. The Project would likely be able to be a source for this need, which is discussed further in the Solid Waste Section of Part 2 of this Study.

Project Partner: Mariposa County Resource Development District (MCRCD) Note this this Project is an example of a public private partnership. The Mariposa County Resource Conservation District, MCRCD, and the Project Applicant worked together to bring in financial support for the development of the Project. The MCRCD was the applicant and now is the grant administrator for the $244,000 Wood Innovations planning grant received in 2016 from the U.S. Forest Service. The project has been tentatively awarded a $5 million EPIC grant; MCRCD was the applicant and will be the grant administrator. 1.2 Specific Notable Environmental and/or Regulatory Settings

1.2.1 Aesthetics The project can generally be seen from one local neighborhood, Mykle Oaks Ranches, from along Highway 49, and from other properties within the Mariposa Industrial Park. There is existing tree cover and hilly topography on the project site and vicinity. These natural attributes, as well as efforts by the Project to blend the project into the locale will minimize the visual impact of this project on the neighborhood.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Figure 4

The LDA MND states that upon the creation of the Mariposa Industrial Park, and later land subdivision, were intentional land use decisions taken to bring industry to Mariposa County, and so while these actions did “not directly impact site aesthetics, there is an indirect impact will include the industrial buildings developed on the site. The county has not established building design or landscape requirements for industrial development in this area; therefore, the threshold of impact is set quite high.” As to the aesthetic issues of building height, light, glare and color, landscaping and outdoor storage those issues are controlled by the PDZ 87-1 development standards, which are described in more detail below. Landscaping shall be done in accordance with the following provisions. Natural vegetation may be deemed appropriate for landscaping purposes when properly maintained. Within fifty feet of all buildings and similar structures, dry grass, brush and other flammable vegetative matter shall be cleared and lower limbs of trees shall be removed to a height of eight (8) feet as may be required by the Mariposa County Fire Department. Other landscaping provisions are as follows: a. The Front Yard Setback Area of each Site should be landscaped with an effective combination of trees, ground cover and shrubbery. All unpaved areas not utilized for parking shall be should be landscaped in a similar manner. b. Side and Rear Yard Setback Areas should be landscaped utilizing ground cover and/or shrub and tree materials. c. Undeveloped areas proposed for future expansion shall be maintained in a brush• free condition. d. Areas used for parking should be landscaped and/or fenced in such a manner as to interrupt or screen said areas from view from access Streets, State Highway 49, and adjacent properties where possible. Plant materials used for this purpose shall consist of lineal or grouped masses of shrubs and/or trees. 12

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Outdoor storage areas shall be visually screened from access Streets, State Highway 49 and adjacent property to the maximum feasible extent. Screening shall form a complete opaque screen up to a point eight (8) feet in vertical height but need not be opaque above that point. No storage shall be permitted between a frontage street and the Building Line. Additionally, fencing and screening is limited to 12 feet. Also, setbacks from the road of 10 feet and 12 feet from lot lines are required. There are also detailed restrictions on the use of signs and advertising displays within Section 4 of the PDZ 87-1. Under PDZ 87-1 lighting may not located more than fifteen feet above ground, nor can it directed off of the premises toward another site or building. Security lighting shall not be restricted from being used to light the exterior of a building or sign, but it shall not be situated in such a manner as to reflect into a street or road and create a hazard to traffic. Additionally, all lighting shall meet the International Dark Sky Standards in order to conform to the General Plan. The height standards applicable to the project are driven by the PDZ 87-1 and the Airport Overlay District requirements. PDZ 87-1 states that “buildings shall not exceed 45 feet for any structure within the Mariposa Industrial Park. This standard shall not apply to radio/communication towers, power transmission towers or similar utility structures. Maximum allowable height for these types of structures is seventy-five feet. In no case shall these standards allow the construction of a building, tower or utility structure which encroaches into the approach zone established by the Mariposa County Airport Zone.” The Project does not propose a building over 45 feet tall, although it does propose a 60 foot tall air exhaust stack (tower) that is a similar utility structure allowed by PDZ 87-1 height standards. The proposed 60 foot tall air exhaust stack does not exceed the 75 foot maximum height allowance for those types of utility structures. The Airport Overlay District requires compliance with the Airport Master Plan and the Mariposa Yosemite Airport Comprehensive Land Use plan height requirements. The proposed air exhaust stack height of 60 feet cannot penetrate the “imaginary conical surface” pursuant to the Airport Plans. This conical surface defines the elevation of which a ground structure may not enter, thereby being the maximum height elevation of ground structures. The Airport Plans prescribe the methodology to measure and calculate the conical surface elevation at given points in relation to the distance from the Airport runway. Based on the methodology, the imaginary conical surface elevation directly above the proposed air exhaust stack location is 2532 feet. At the top of the proposed air exhaust stack of 60 feet, the elevation is 2454 feet. The top of the proposed air exhaust stack height is at an elevation of 2454 feet, being 78 feet below the imaginary conical surface elevation of 2454 feet and therefore in compliance with the Airport Plans and Airport Overlay District. To illustrate this, an exhibit of the surfaces as they relate to the height limitations for airport safety was prepared by a licensed land surveyor along with reference to Mead Hunt Airport Layout and Airspace plan sheets included as Attachment F.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

1.2 Agriculture and Forestry Resources

1.2.1 Agriculture Resources

The property is within an already designated industrial area that will not impact any agricultural or grazing activities within Mariposa County.

1.2.2 Forestry Resources

Environmental Setting

Numerous large fires have occurred in the region in 2017 including the Detwiler, Railroad, Peak and Cathedral Spires Fires.. The very large Detwiler Fire, which burned over 81,000 acres and destroyed over 50 homes, with half the County’s population and the town of Mariposa evacuated. The Detwiler fire was one of the worst in County history. In addition, there were a number of other large fires in the Sierra that burned for months, including the Empire and Sugar Pine fires in the Sierra National Forest and Yosemite National Park that impacted the County.

One hundred years of fire suppression has created overstocked forests with more fuel and fire- susceptible trees dead trees due to tree mortality, all leading to larger, more intense wildfires. Forest fuel reduction is effective at reducing future fire intensity and improving tree health without negatively impacting understory vegetation, soil density or erosion, or wildlife. This project is estimated to use 12,000 BDT per year of woody biomass. While in the short-term, most of that fuel will come from removing excess vegetation from around public infrastructure and homes, the facility will provide a place to take biomass from surrounding forests when funding for that activity is available and would lead to significant ecological improvement in surrounding forests. Fuels reduction limits the wildfire risk and, thus, helps prevent the loss of carbon sequestered, increasing greenhouse gas sequestration. Furthermore, decay of forest floor woody materials leads to anaerobic conditions which release methane, a very powerful greenhouse gas, 86 times more warming than carbon dioxide. The complete combustion associated with the Cortus WoodRoll® process minimizes not only methane production but also the production of black carbon or soot released during forest fires and open pile burning, again minimizing the short-lived greenhouse gas impact associated with the poorly managed forests.

Land ownership is important as a driver of vegetation management objectives and therefore the availability of acreage for feedstock sourcing. There are over 5 million total acres within the FSA, with approximately 58 percent in private ownership and 42 percent under state or federal jurisdiction.

The USDA Forest Service (USFS) manages three national forests within the FSA: Sierra National Forest, Stanislaus National Forest and a very small section of the Inyo National Forest. Each of the three national forests has designated wilderness areas that remove acreage from consideration for feedstock sourcing. All of Yosemite National Park, and most of the Yosemite Wilderness, are under National Park Service (NPS) jurisdiction and fall within the FSA. The Sierra National Forest non-wilderness has 33 percent of the forested land in the FSA. The 14

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Stanislaus National Forest non-wilderness has 26 percent; however, almost a third of the forested acreage in the Stanislaus National Forest has been removed from consideration for feedstock sourcing due to the large-scale 2013 Rim Fire. Yosemite National Park does have active forest management programs, although the forested acres potentially available for feedstock have also been reduced by the Rim Fire.

There are approximately 1.5 million forested acres in the Mariposa FSA after acreage reductions for USFS and NPS wilderness and removal of all Rim Fire burned acres. Accounting for adverse slopes greater than 35 percent the total forest landscape considered accessible for feedstock sourcing amounts to approximately 1.1 million acres.

It is important to note that private lands constitute 43% of the forested acreage, making forest management activity on private lands a potentially significant source of feedstock materials. Although there are some contiguous parcels of private forest lands in the Stanislaus and Sierra National Forest, most private land forests are on smaller discontinuous acreage. Shrub land acreage within the FSA is almost all on private lands.

Additionally, Mariposa has been one of the hardest hit counties from tree mortality. Figure 5

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

The County has done significant work to determine the location of dead and dying trees within the county, culminating in a maps and data project, as well as tree removal plan, which are both included in this packet as Attachments G and H.

Even before the terrible tree mortality occurred, there was adequate wood waste to supply this facility from woody biomass debris from fuel reduction and other property management. This facility will only use waste wood that come from projects that are reducing wildfire risk and improving public safety, e.g. woody biomass from under PG&E power lines roads and homes, tree mortality sources or waste from sustainable forest practice. No trees will be cut specifically as fuel for this project. To illustrate this point about wood availability, here is an image from CALFIRE’s GIS mapping tool that shows where tree mortality is located, with over 101 million trees identified Statewide.

Figure 6

More information about the project’s feedstock options and use of already down trees can be found within the feedstock assessment, which is Attachment R, as well as one can interact live on CALFIRE’s tree mortality viewer located at http://www.fire.ca.gov/treetaskforce/index

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Regulatory Setting

As described above, Mariposa County is an area besieged with catastrophic wildfire. Due to long periods of artificial fire suppression, the forests have become overstocked and at risk for burning in ways in which the forests cannot recover quickly, and bringing devastating impacts on the people who live in these areas. In response to this and other wood waste challenges in California, in September 2012, Governor Brown signed SB 1122 (Rubio, 2012) into law, requiring an incremental 250 megawatts (MW) of renewable Feed-in Tariff (FIT) procurement from small-scale bioenergy projects that commence operation on or after June 1, 2013.

The statute requires that each of California’s three large investor-owned utilities (PG&E, SCE, and SDG&E) must procure a share of the statute’s 250-MW requirement based on the ratio of each utility’s peak demand to statewide peak demand. Additionally, the statute orders the California Public Utilities Commission (CPUC) to allocate the 250-MW procurement requirement among the following categories:

i) For biogas from wastewater treatment, municipal organic waste diversion, food processing and codigestion (110 MW) ii) For dairy and other agricultural bioenergy (90 MW) iii) For bioenergy using byproducts of sustainable forest management (50 MW)

The objective of SB 1122 was to encourage forest thinning and fuels reduction projects on private and federal forest land through providing local small biomass conversion facilities. Shasta County was identified as an area with volumes and opportunity for success under the program (Black & Veatch, 2013).

The CPUC adopted a checklist developed by CALFIRE in December 2014 to define what types of forest management activities would be defined under SB 1122 as “sustainable.” Biomass from the following forest management activities was determined to meet the requirements of the program:

i) Fire Threat Reduction – biomass feedstock which originates from fuel reduction activities identified in a fire plan approved by CAL FIRE or other appropriate state, local or federal agency. On federal lands this includes fuel reduction activities approved under 36 CFR 220.6(e)(6)ii and (12) thru (14), ii) Fire Safe Clearance Activities – biomass feedstock originating from fuel reduction activities conducted to comply with PRC Sections 4290 and 4291. This would include biomass feedstocks from timber operations conducted in conformance with 14 CCR 1038(c) 150’ Fuel Reduction Exemption, as well as projects that fall under 14 CCR 1052.4 (Emergency for Fuel Hazard Reduction Exemption, as well as projects that fall under 14 CCR 1052.4 (Emergency for Fuel Hazard Reduction), 14 CCR 1051.3-1051.7 (Modified THP for Fuel Hazard Reduction), and 14 CCR 1038(i) Forest Fire Prevention Exemption, Categorical exclusions on federal lands approved under 36 CFR 220.6(e).(6)ii.,

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

iii) Infrastructure Clearance Projects – biomass feedstock derived from fuel reduction activities undertaken by or on behalf of a utility or local, state or federal agency for the purposes of protecting infrastructure including but not limited to: power lines, poles, towers, substations, switch yards, material storage areas, construction camps, roads, railways, etc. this includes timber operations conducted pursuant to 14 CC1104. 1(b),(c),(d),(e),(f),&(g), iv) Other Sustainable Forest Management – biomass feedstock derived from sustainable forest management activities that accomplish one or more of the following: 1) forest management applications that maintain biodiversity, productivity, and regeneration capacity of forests in support of ecological, economic and social needs, 2) contributes to forest restoration and ecosystem sustainability, 3) reduces fire threat through removal of surface and ladder fuels to reduce the likelihood of active crown fire and/or surface fire intensity that would result in excessive levels of mortality and loss of forest cover or, 4) contributes to restoration of unique habitats within forested landscapes.

A form and checklist was developed to further define the Category IV activities. In addition, the following project types were defined to meet the sustainable forest management criteria and were exempted from submitting the additional form and checklist:

1) Sustainable Forest Management projects implemented on state, federal and private ownership which involve meadow restoration, restoration of wetlands, restoration of aspen and other similar activities which are undertaken for restoration purposes and are subject to environmental review under CEQA or NEPA. 2) Operations conducted pursuant to an approved Non-Industrial Timber Management Plan where the plan or amendment to the plan evaluates and provides for a discussion of intended biomass operations and byproducts that may have potential significant adverse impacts, evaluates potential significant impacts, and mitigates potential significant impacts. 3) Operations conducted pursuant to an approved Timber Harvesting Plan or Modified Timber Harvesting Plans on non-industrial timberland ownerships where the landowner is not primarily engaged in the manufacture of wood products and where the approved plan or amendment to the plan evaluates and provides for a discussion of intended biomass operations and byproducts that may have potential significant impacts, evaluates potential significant impacts, and mitigates potential significant impact. 4) Operations with a total estimated volume of less than 250 bone dry tons.

The checklist further defines activities considered eligible.

This Project will be obtaining a Power Purchase Agreement that will be regulated by this Program’s feedstock requirements. These requirements ensure that that wood used at these facilities is truly waste wood that has not been grown for the purposes of energy production. Additionally, while the PPA prices for electricity are high, the economics of the value of large diameter commercially viable wood for wood products highly outweighs the use of wood for

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 electricity in California, so it is not expected that this project will trigger commercial wood harvests.

1.3 Air Quality

1.3.1 Regulatory Setting

Mariposa County Air Pollution Control District is a part of the Mountain Counties Air Basin, which is comprised of seven air districts: the Northern Sierra AQMD, which includes Plumas, Sierra, and Nevada Counties; a portion of the Placer County APCD that consists of the central portion of Placer County; a portion of the El Dorado County AQMD, which consists of the western portion of El Dorado County; the Amador County APCD, which consists of Amador County; the Calaveras County APCD, which consists of Calaveras County; and the Tuolumne County APCD, which consists of Tuolumne County. The Amador and Tuolumne air districts, and the western portion of the Mariposa air district are designated as unclassified for the State PM10 standards, since no PM10 data are available for these areas with the rest of the Mountain Counties Air Basin designated as unclassified – available data are insufficient to support designation as attainment or nonattainment.

1.3.1.1 Criteria Pollutants

Criteria pollutants from stationary sources regulated by the Mariposa include:

· Ozone · Carbon Monoxide · Nitrogen Dioxide · Sulfur Dioxide · Particulate · Lead · Odor · Toxic Air Contaminants

Ozone (O3): Ozone (O3) is a photochemical oxidant and the major component of smog. Ozone in the upper atmosphere is beneficial to life by shielding the earth from ultraviolet radiation; however, high concentrations of ozone at ground level are a major health and environmental concern. Ozone is not directly emitted into the air but is formed through complex chemical reactions between precursor emissions of reactive organic gases (ROG) and oxides of nitrogen (NOx) in the presence of sunlight. These reactions are stimulated by sunlight and temperature so that peak ozone levels occur typically during the warmer times of the year. Both ROGs and NOx are emitted by transportation and industrial sources. ROGs are emitted from sources as diverse as autos, chemical manufacturing, dry cleaners, paint shops, and other sources using solvents.

Carbon Monoxide: Carbon monoxide (CO) is a colorless, odorless, and poisonous gas produced by incomplete burning of carbon in fuels. When CO enters the bloodstream, it 19

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 reduces the delivery of oxygen to the body’s organs and tissues. Those who suffer from cardiovascular disease, particularly those with angina or peripheral vascular disease, are at higher risk. Exposure to elevated levels of CO can cause impairment of visual perception, manual dexterity, learning ability, and performance of complex tasks. Automobile use is the primary source of carbon monoxide.

Nitrogen Dioxide (NO2): “Nitrogen oxides” (NOx) is a term used in reference to the mono- nitrogen oxides NO and NO2. It is a highly reactive gas that is present in all urban atmospheres. NO2 can irritate the lungs, cause bronchitis and pneumonia, and lower resistance to respiratory infections. Nitrogen oxides are an important precursor both to ozone (O3) and acid rain and may affect both terrestrial and aquatic ecosystems. The major mechanism for the formation of NO2 in the atmosphere is the oxidation of the primary air pollutant nitric oxide (NO). NOx plays a major role in the atmospheric reactions that produce O3. NOx forms whenever combustion occurs in the presence of nitrogen. Transportation and stationary fuel combustion sources such as electric utility and industrial boilers are the primary anthropogenic sources of NOx.

Sulfur Dioxide: Sulfur dioxide (SO2) affects breathing and, in high doses, can aggravate existing respiratory and cardiovascular disease. Sulfur compounds in the air contribute to visibility impairment in large parts of the country. Ambient SO2 results largely from stationary sources such as coal and oil combustion, steel mills, refineries, pulp and paper mills, and nonferrous smelters.

Particulate Matter (PM10 and PM2.5): Particulate matter includes dust, dirt, soot, smoke, and liquid droplets directly emitted into the air by sources such as factories, power plants, cars, construction activity, fires, and natural windblown dust. Particles formed in the atmosphere by condensation or the transformation of emitted gases such as SO2 and VOCs are also considered particulate matter.

Lead (Pb): Lead (Pb) exposure can occur through multiple pathways, primarily inhalation and ingestion. Lead exposure can cause seizures, mental retardation, and behavioral disorders. Low doses of lead can lead to central nervous system damage. Lead may also be a factor in high blood pressure and heart disease.

Odors: Typically, odors are regarded as an annoyance rather than a health hazard. However, manifestations of a person’s reaction to odors can range from psychological (e.g., irritation or anxiety) to physiological (e.g., circulatory and respiratory effects, nausea, vomiting, and headache).

The human nose is the sole sensing device for odors. The ability to detect odors varies among the population and is subjective. Certain individuals may have the ability to smell minute quantities of specific substances while others may not have the same sensitivity. In addition, people may have different reactions to the same odor; in fact, an odor that is offensive to one may be acceptable to another.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

It is also important to note that an unfamiliar odor is more easily detected and is, therefore, more likely to cause complaints than a familiar one. When an odorous sample is progressively diluted, the odorant concentration decreases. As this occurs, the odor intensity decreases and eventually drops below the level of detection, meaning it is not recognized by the average human.

1.3.1.2 Toxic Air Contaminants

Toxic Air Contaminants (TACs) are pollutants that can be expected to result in an increase in mortality or serious illness or that may pose a hazard to human health. Health effects include cancer, birth defects, neurological damage, damage to the body’s natural defense system, and diseases that lead to death. Although ambient air quality standards exist for criteria pollutants, no such standards exist for TACs.

Many pollutants are identified as TACs because of their carcinogenic effects or because of their acute or chronic health risks. For TACs that are known or suspected carcinogens, the California Air Resources Board (CARB) has consistently found that there are no thresholds below which exposure is free of risk. For some TACs, a unit risk factor can be developed to evaluate cancer risk. For acute and chronic health risks, a similar factor called a Hazard Index is used to evaluate risk. CARB established a statewide comprehensive air toxics program, the Toxic Air Contaminant Identification and Control Act (Assembly Bill [AB] 1807), to reduce exposure to air toxics. The Air Toxics “Hot Spots” Information and Assessment Act (AB 2588) supplements the AB 1807 program by requiring a statewide air toxics inventory, notification of people exposed to a significant health risk, and facility plans to reduce these risks.

According to the California Almanac of Emissions and Air Quality (ARB 2009), the majority of the health risks estimated from TACs can be attributed to few compounds, the most important being diesel PM. Diesel PM is different from other TACs in that it is not a single substance, but instead a complex mixture of hundreds of substances. Although diesel PM is emitted by diesel‐ fueled internal combustion engines, the composition of the emissions varies depending on engine type, operating conditions, fuel composition, lubricating oil, and whether an emissions control system is being used.

1.3.1.3 Ambient Air Quality Standards

Both the federal and state governments regulate ambient air quality.

Federal: The Environmental Protection Agency (EPA) established National Ambient Air Quality Standards (NAAQS) for several air pollutants, referred to as “criteria pollutants” under the Federal Clean Air Act (FCAA) of 1970. The six criteria pollutants are ozone, particulate matter (PM10), nitrogen oxides (NOx), carbon monoxide (CO), lead, and sulfur dioxide (SO2). The standards for these pollutants are based on evidence that exposure is harmful to public health. The Clean Air Act identifies two national ambient air quality standards – primary and secondary. Primary standards provide public health protection, including protection of “sensitive receptors” such as asthmatics, children and the elderly. Secondary Standards provide 21

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 protection for public welfare and the environment. Table 1 lists the Federal ambient air quality standards.

State: California passed the California Clean Air Act (CCAA) in 1988. The CCAA established ambient air quality standards. The California standards are more stringent and include hydrogen sulfide (H2S), vinyl chloride, and visibility reducing particles in addition to the six federal criteria pollutants. The CARB is responsible for establishing air quality standards, regulating mobile emission sources and overseeing the activities of the air pollution control districts (APCDs) and the air quality management districts (AQMDs).

Attainment Status: In accordance with the FCAA and the CCAA, CARB designates areas of the state as attainment, nonattainment, or unclassified with respect to applicable standards. An “attainment” designation for an area signifies that pollutant concentrations do not violate the applicable standard in that area. A “nonattainment” designation indicates that a pollutant concentration violated the applicable standard at least once, excluding those occasions when a violation was caused by an exceptional event, as defined in the criteria. The CCAA divides districts into moderate, serious, and severe air pollution categories, with increasingly stringent control requirements mandated for each category.

The CARB has designated Mariposa County APCD is unclassified, with generally good air quality.

1.3.1.4 MCAPCD Significance Thresholds and Potential to Emit

The MCAPCD has not formally adopted thresholds of significant impact for the purposes of CEQA review. Thresholds of potential significant impact were nonetheless identified in the 2006 Final Environmental Impact Report prepared for the Mariposa County General Plan. In Table 4.8-1 of the Final EIR[1], the emissions in excess of 100 TPY of any criteria air contaminant would be the threshold for significant impact. In addition, the values listed in Table 4 were further confirmed by the MCAPCD[2].

Table A (Table 4. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 4. MCAPCD Significance Thresholds

Project NOx VOC CO SOx PM10 PM2.5 Phase (ROG)

Operational 100 TPY 100 TPY 100 100 100 TPY 100 TPY TPY TPY Construction 100 TPY 100 TPY 100 100 100 TPY 100 TPY TPY TPY

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

All of these regulations are taken into account within the Attached Air Study, found at Attachment I, and are analyzed in the Air Quality Section below.

[1] http://ca-mariposacounty.civicplus.com/DocumentCenter/Home/View/3113 [2] Personal Communication with David L. Conway, MCAPCD, September 30, 2017

1.4 Biological Resources

1.4.1 Regulatory Setting

The United States Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service implement the Federal Endangered Species Act of 1973 (FESA) (16 USC §1531 etseq.). Threatened and endangered species on the federal list (50 CFR §17.11, 17.12) are protected from “take” (direct or indirect harm), unless a FESA Section 10 Permit is granted or a FESA Section 7 Biological Opinion with incidental take provisions is rendered. Pursuant to the requirements of FESA, an agency reviewing a proposed project within its jurisdiction must determine whether any federally listed species may be present in the project area and determine whether the proposed project will have a potentially significant impact upon such species. Under FESA, habitat loss is considered to be an impact to the species. In addition, the agency is required to determine whether the project is likely to jeopardize the continued existence of any species proposed to be listed under FESA or result in the destruction or adverse modification of critical habitat proposed to be designated for such species (16 USC §1536[3], [4]). Therefore, project-related impacts to these species or their habitats would be considered significant and would require mitigation. Species that are candidates for listing are not protected under FESA; however, USFWS advises that a candidate species could be elevated to listed status at any time, And, therefore, applicants should regard these species with special consideration

The California Endangered Species Act of 1970 (CESA) (California Fish and Game Code §2050 et seq., and CCR Title 14, §670.2, 670.51) prohibits “take” (defined as hunt, pursue, catch, capture, or kill) of species listed under CESA. A CESA permit must be obtained if a project will result in take of listed species, either during construction or over the life of the project. Section 2081 establishes an incidental take permit program for state-listed species. Under CESA, California Department of Fish and Game (CDFG) has the responsibility for maintaining a list of threatened and endangered species designated under state law (CFG Code 2070). CDFG also maintains lists of species of special concern, which serve as “watch lists.” Pursuant to requirements of CESA, an agency reviewing proposed projects within its jurisdiction must determine whether any state-listed species may be present in the Study Area and determine whether the proposed project will have a potentially significant impact upon such species. Project-related impacts to species on the CESA list would be considered significant and would require mitigation.

The California Native Plant Protection Act of 1977 (CFG Code §1900 et seq.) requires CDFG to establish criteria for determining if a species or variety of native plant is endangered or rare. Section 19131 of the code requires that landowners notify CDFG at least 10 days prior to initiating activities that will destroy a listed plant to allow the salvage of plant material. 23

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California Environmental Quality Act (CEQA) (Public Resources Code §15380) defines “rare” in a broader sense than the definitions of threatened, endangered, or fully protected. Under the CEQA definition, CDFG can request additional consideration of species not otherwise protected. CEQA requires that the impacts of a project upon environmental resources must be analyzed and assessed using criteria determined by the lead agency. Sensitive species that would qualify for listing but are not currently listed may be afforded protection under CEQA.

The CEQA Guidelines (§15065) require that a substantial reduction in numbers of a rare or endangered species be considered a significant effect. CEQA Guidelines (§15380) provide for assessment of unlisted species as rare or endangered under CEQA if the species can be shown to meet the criteria for listing. Plant species on the California Native Plant Society (CNPS) Lists 1A, 1B, or 2 are typically considered rare under CEQA. California “Species of Special Concern” is a category conferred by CDFG on those species that are indicators of regional habitat changes or are considered potential future protected species. While they do not have statutory protection, Species of Special Concern are typically considered rare under CEQA and thereby warrant specific protection measures.

1.4.2 Environmental Setting

The Project Area is located within the southern Sierra Nevada foothills geographic sub-region, which is contained within the Sierra Nevada Mountains geographic subdivision of the larger California Floristic Province (Baldwin et al. 2012). This region has a Mediterranean-type climate, characterized by distinct seasons of hot, dry summers and wet, moderately- cold winters. The Project Area and vicinity is in climate Zone 7 “Gray Pine Belt,” with hot summers and mild but pronounced winters (Brenzel 2001). The topography of the Project Area is hilly with slopes that drain northward. The elevation ranges from approximately 2,320 feet to 2,410 feet above mean sea level. The Project Area is located within the Agua Fria Creek watershed, which flows to Mariposa Creek and then the San Joaquin River. The surrounding land uses are as follows: to the south and west, open space; to the north, rural residential and open space; and to east, industrial uses, including the Mariposa Landfill, Composting, and Recycling Center, several small manufacturing firms, Outback Materials (sand and gravel) and a Pacific Gas & Electric substation.

The Project Area contains 3 general vegetation community types: ruderal/developed; gray pine woodland and foothill chaparral. The geology underlying the study area includes ultramafic (serpentine) and meta volcanic rock types (California Geological Survey, 2010). These habitat types are discussed in detail in the Biological Resource Assessment, and are delineated in the Exhibits, within the Biological Study done for the Project, which can be found as Attachment J. The California Natural Diversity Database does not show any special-status habitats within 5 miles of the Study Area. The Project Area is not located within any adopted Habitat Conservation Plan or Natural Community Conservation Plan.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Ruderal/Developed

Ruderal/Developed habitat is found within the disturbed and graded portions of the Project Area, including roads and the graveled building pad. Vegetation within this habitat type consists primarily of nonnative weedy or invasive ruderal species lacking a consistent community structure. This habitat is classified as Holland vegetation type –“Urban –11100,” and “Urban” and “Barren” wildlife habitat types by WHR. This habitat type provides limited resources for wildlife and is utilized primarily by species tolerant of human activities. Weedy species sighted include compact brome (Bromus madrietensis), poverty brome (Bromus sterilis), rattail six weeks grass (Festuca myuros), red-stem filaree (Erodium cicutarium), smooth cat’s ear (Hypochaeris glabra), Heermann’s tarplant (Holocarpha heermannii), bird’s-foot trefoil (Lotus corniculatus), erect plantain (Plantago erecta), and common groundsel (Senecio vulgare). The disturbed and altered condition of these lands greatly reduces their habitat value and ability to sustain rare plants or diverse wildlife assemblages. However, common, disturbance-tolerant species do occur in these lands. None of the target species are expected to occur in the Ruderal/Developed community type because of competition from invasive, non-native species.

Grey Pine Woodland

Gray Pine Woodland is the dominant habitat type within the Project Area. Vegetation within this community type consists of scattered trees with an understory of shrubs. This habitat is classified as Holland vegetation type –“Open Digger Pine Woodland–71310,”“Blue Oak – Foothill Pine” wildlife habitat type by WHR, and “Pinus sabiniana Wood land Alliance (Foothill Pine Woodland)” vegetation type by Sawyer et al (2009). This habitat type provides significant food and breeding resources for wildlife. Species sighted include Foothill pine (Pinus sabiniana), interior live-oak (Quercus wislizeni), blue oak (Quercus douglasii), wedgeleaf ceanothus (Ceanothus cuneatus), poison-oak (Toxicodendron diversilobum), while- leaf manzanita (Arctostaphylos viscida), toyon (Heteromeles arbutifolia), chamise (Adenostema fasciculatum), poverty brome, compact brome, ripgut brome (Bromus diandrus), Italian thistle (Carduus pycnocephalus), Mariposa lily (Calochortussp.), wavy-leaved soaproot (Chlorogalum pomeridianum), bluedicks (Dichelostemma capitatum), red-stem filaree, Sierra fawn-lily (Erythronium multiscapoideum), bedstraw (Galiumspp.), sock destroyer (Torilisspp.),and winter vetch (Vicia villosa). This habitat occurs primarily on soils derived from metavolcanic parent material, but transitions onto serpentine in the southwest corner of the Project Area. The portions of the Project Area containing gray pine woodland habitat have a low to moderate potential for occurrence of the following plants known to occur in woodland habitats: Mariposa daisy, Madera leptosiphon, Mariposa lupine, and slender-stalked monkeyflower. However, these rare species were not detected during the botanical survey, which is found herein as Attachment K.

Foothill Chaparral

Vegetation within this community type consists of annual herbs with scattered shrubs and occasional trees. This habitat is classified as Holland vegetation type –“Buck Brush Chaparral –37810,” and “Ceanothus cuneatus Alliance (Wedge Leaf Ceanothus Chaparral)”vegetation

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 type by Sawyer et al (2009).Where chaparral integrates into the gray pine woodland, it is classified as the community 87.130.04 Foothill Pine -Interior Live Oak / Wedge leaf Ceanothus [Pinus sabiniana-Quercus wislizeni/Ceanothus cuneatus] (Sawyer et al. 2009). Where it intersects serpentine soils, it is classified as 87.130.01 Serpentine Digger Pine Chaparral Woodland. A special chaparral community type occurs in a narrow band along the southern edge of the Study Area and continues on adjacent parcels to the south, southeast, and southwest. Sawyer et al (2009) describes this community as 37.000.06 Mixed Serpentine Chaparral. This community occurs primarily on soils derived from serpentine bedrock parent material. Shrub cover is much lower compared to the adjacent foothill pine woodland because serpentine soils are high in several potentially toxic elements including iron and magnesium and low in required nutrients such as calcium. This restrictive soil type is home to numerous endemic plant species, many of which are rare. Species observed include wedge leaf ceanothus, gray pine, poison oak, wavy-leaved soap root, erect plantain (Plantago erecta), seep monkeyflower (Mimulus guttatus), shining peppergrass (Lepidium nitidum), annual checkerbloom (Sidalcea calycosa) and common goldfields (Lasthenia gracilis). The portions of the Study Area containing serpentine soils have a moderate to high potential for occurrence of the following plants known to occur on serpentine soils: Mariposa clarkia, Beaked clarkia, Mariposa cryptantha, Congdon’s lomatium and shaggy hair lupine. The field survey failed to detect these rare species. This community equates to the “Mixed Chaparral” wildlife habitat type by WHR. The restrictive soil chemistry within this vegetation type limits the overall cover and therefore the ability to sustain diverse wildlife assemblages. However, many common species do occur in these habitats.

During the field survey on March 23, 2017 no special-status species were observed within the Study Area. In the vicinity of the Study Area, 2 special-status species have been reported in the CNDDB, and 5 species have special habitat requirements that are present within the Study Area.

Table B (Table 1. from Botanical Study)

Table 1. Special-status Plant Species Occurring within 5 Miles of Study Area (CNDDB, 2017)

Common Name Bloo Scientific Name Status min General Habitat Microhabitat g Chaparral, cismontane On serpentine. Several occurrences Mariposa clarkia CNPS 1B.2 APprer-i woodland. occur in the foothill woodland/riparian Clarkia biloba ssp. australis Jodul ecotone. 300-1460 m. Cismontane North-facing slopes; sometimes on Beaked clarkia CNPS 1B.3 Apr- woodland, valley and sandstone. 60-500 m. Clarkia rostrata May foothill grassland. Mariposa cryptantha Apr- Chaparral. On serpentine outcrops. 200-650 m. Cryptantha mariposae CNPS 1B.3 Jun

Mariposa daisy Jun- Cismontane woodland. One site known. 600-800 m. Erigeron mariposanus CNPS 1A Aug

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Cismontane Dry slopes; often on decomposed granite Madera leptosiphon CNPS 1B.2 Apr- woodland, lower in woodland. 80-1575m. Leptosiphon serrulatus May montane coniferous Cforisemontst. ane woodland, Serpentine soils with serpentine Congdon's lomatium CNPS 1B.2 May- chaparral. chaparral plants and grey pines. 300- Lomatium congdonii Jun 2100 m.

Feder Chaparral, cismontane Decomposed granitic sand on hilltops Mariposa lupine ally Apr- woodland. and hillsides on western slope of the Lupinus citrinus var. threat May Sierra Nevada, mostly southern- deflexus ened; exposure. 400-640m. CNPS 1B.2 Apr- Chaparral, cismontane Open rocky slopes of serpentine. Mostly Shaggyhair lupine CNPS 1B.2 May woodland. on serpentine chaparral surrounded by Lupinus spectabilis gray pine woodland. 260-825 m.

Apr- Chaparral. Disturbed places such as burns and Slender-stalked CNPS 1B.2 Jun railroad grades; also on monkeyflow thin granitic soil in cracks in large granite Mimulus gracilipes rocks. 500-1300m.

No special status species were detected at the site, but suggestions are made within the Biological and Botanical studies to take precautions during the construction of the site due to the fact that some species may arrive between time of use permit approval and construction.

1.5 Cultural Resources

A historical resource is a resource listed in, or determined to be eligible for listing in, the California Register of Historical Resources (CRHR) (Public Resources Code [PRC] Section 21084.1), a resource included in a local register of historical resources (PRC Section 15064.5[a][2]), or any object, building, structure, site, area, place, record, or manuscript which a lead agency determines to be historically significant (PRC Section 15064.5[a][3]). PRC Section 5024.1 requires evaluation of historical resources to determine their eligibility for listing in the CRHR. The purpose of the register is to maintain listings of the State's historical resources and to indicate which properties are to be protected from substantial adverse change. The criteria for listing resources in the CRHR were expressly developed to be in accordance with previously established federal criteria for listing in the National Register of Historic Places (NRHP).

A current study was completed under the provisions of CEQA. Section 21083.2 of the statute and Section 15064.5 of the CEQA Guidelines provide instructions for a lead agency to consider the effects of Projects on historical resources and cultural resources. The Cultural Resources Inventory for the Mariposa Biomass Project was prepared by Natural Investigations Company in March of 2017. The confidential report was made available to tribes and agencies upon request. Consultation was conducted in accordance with the requirements of PRC 21080.3.1 & 2 and as a result voluntary mitigation is included. The confidential Cultural Resources Study (Attachment L) is not included, although is available at Mariposa County Planning Department. 27

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

1.6 Geology / Soils

Environmental Setting: Geology

The Project is located on the western slope of the Sierra Nevada Mountains in the Sierra Nevada physiographic province (Norris and Webb 1990). The Sierra Nevada is approximately 50 miles wide and extends for 400 miles paralleling California’s eastern border south from the Cascade Range to the central Transverse Ranges. The geology of the Sierra Nevada is characterized primarily by igneous and metamorphic rocks of diverse composition and age that also contains gold-bearing veins in the northwest trending Mother Lode. The Mother Lode region in the Sierra Nevada extends some 150 miles southward from El Dorado County, passes through Calaveras County, and ends in Mariposa County.

Review of geologic maps and reports indicates the Project area is underlain by Late Jurassic age (161–145 million years) metavolcanic rocks of the Mariposa Formation, which also extends to the northeast (Clark 1964;Strand 1967). Northwest-southeast trending bands of Mesozoic (251– 65 million years) ultrabasic intrusive rocks are mapped north and south of SR 49. To the east is a large complex of Mesozoic granitic rocks (part of the Sierra Nevada batholith), with Late Jurassic marine deposits of the Briceburg Formation to the north. Serpentine is found in the project vicinity and therefore applicable Health requirements must be followed for grading where naturally occurring asbestos may be located.

Environmental Setting: Soils

Soils in this rocky outcrop area are mapped by the U.S. Department of Agriculture (USDA) National Resource Conservation Service(NRCS) as the Henneke gravelly loam series (California Soil Resource Lab 2017; Soil Survey Staff 2017). These weakly developed, well drained soils formed in material weathered from serpentine and similar rocks. The depth to bedrock (R horizon) is typically at only 8 inches below the surface, beneath a very thin (0–0.5 inch) organic horizon of partially decomposed leaf litter with gravels, a thin brown gravelly loam A horizon (0–3 inches), and a very gravelly clay loam Bt (argillic) horizon (10–19 inches). Located on mountainous ridges and slopes of the Sierra Nevada, with a very shallow depth to bedrock, buried soils representing former landscapes are not described nor expected for this weakly developed soil series.

1.7 Greenhouse Gas Emissions

1.7.1 Regulatory Setting - Federal

Mandatory Greenhouse Gas Reporting Rule: The EPA issued a final rule for mandatory reporting of greenhouse gas (GHG) emissions from large emission sources in the United States on September 22, 2009. This rule requires accurate annual reporting of GHG emissions data from facilities that emit 25,000 metric tons or more of CO2 per year. This data is publicly available data and allows reporters to track emissions, compare them to similar facilities, and aid in identifying cost-effective opportunities to reduce emissions in the future. For a majority

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 of facilities, the reporting is at the facility level. Approximately 85 percent of total U.S. GHG emissions, from approximately 10,000 facilities, are subject to this rule.

Energy Policy Act of 2005: The Energy Policy Act of 2005 was signed into law on August 8, 2005. Generally, the Act provides for renewed and expanded tax credits for electricity generated by qualified energy sources; provides bond financing, tax incentives, grants, and loan guarantees for a clean renewable energy and rural community electrification; and establishes a federal purchase requirement for renewable energy.

The Clean Power Plan of 2015: The EPA has adopted the “Clean Power Plan” which sets the goal of 30 percent reduction in CO2 by 2030 based on 2005 levels. It also spurs reductions in criteria pollutants and air toxics and instigates renewable energy projects. It is not expected that this plan or rules associated with it will effect California industry because our state requirements are more stringent than those described in this Plan.

1.7.2 Regulatory Setting – State

The Governor’s Emergency Proclamation of October 30, 2015: Governor Brown announced on October 30, 2015, that the significant number of dead and dying trees due to drought and bark beetle infestation have left the State’s forests in such a desperate state that immediate and decisive actions are needed at a regulatory level to deal with the crisis. The construction of new biomass facilities under the BioMAT program, such as this one, are specifically encouraged and many state agencies are tasked to support such projects to the extent possible.

Bioenergy Action Plan – Executive Order #S-06-06: The Bioenergy Action Plan establishes targets for the use and production of biofuels and biopower and directs state agencies to advance biomass programs in California. The Order establishes targets to increase the production and use of bioenergy. These targets include: produce a minimum of 20 percent of its biofuels within California by 2010, 40 percent by 2020, and 75 percent by 2050.

California Executive Orders S-3-05 and Assembly Bill 32: Governor Arnold Schwarzenegger signed Executive Order S-3-05 on June 1, 2005. The goal of this Order is to reduce California’s GHG emissions to 2000 levels by 2010, 1990 levels by 2020, and 80 percent below 1990 levels by 2050. This goal was reinforced by the passage of Assembly Bill 32 (AB32), the Global Warming Solutions Act of 2006. AB 32 sets the same GHG emissions reduction goals but mandates that CARB create a plan using market mechanisms to implement rules to achieve “real, quantifiable, cost-effective reductions of greenhouse gases.”

In 2008, CARB adopted the Climate Change Scoping Plan (Scoping Plan) which details CARB’s plans to achieve the GHG reductions required by AB 32. The Scoping Plan calls for the largest reductions in GHG emissions to be achieved by implementing improved emissions standards for light-duty vehicles, the Low-Carbon Fuel Standard, energy efficiency measures in buildings and appliances and the widespread development of combined heat and power systems, and a renewable portfolio standard for electricity production.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

The First Update to the Scoping Plan was approved by the Board on May 22, 2014, and builds upon the initial Scoping Plan with new strategies and recommendations. The First Update identifies opportunities to leverage existing and new funds to further drive GHG emission reductions through strategic planning and targeted low carbon investments. The First Update defines ARB’s climate change priorities for the next five years and also sets the groundwork to reach long-term goals set forth in Executive Orders S-3-05 and B-16-2012. The Update highlights California’s progress toward meeting the “near-term” 2020 GHG emission reduction goals defined in the initial Scoping Plan. It also evaluates how to align the State’s “longer- term” GHG reduction strategies with other State policy priorities for water, waste, natural resources, clean energy, transportation, and land use.

Senate Bill 1368: SB 1368 requires the California Energy Commission (CEC) and the CPUC to set a global warming emissions standard for electricity used in California regardless of whether the electricity is generated in-state or purchased from plants in other states. The standard applies to any new long-term financial contracts for baseload electricity, and applies both to investor-owned utilities and municipal utilities. The standard for baseload generation owned by, or under long-term contract to, publicly owned utilities, is an emissions performance standard (EPS) of 1,100 lbs CO2 per megawatt-hour (MWh). However, the CPUC has determined that biomass generation of electricity is EPS compliant because alternative means of disposing biomass, such as open-air burning and landfill deposition, have the potential to generate greater concentrations of GHG in the atmosphere, including methane.

Senate Bills 1078 and 107 and Executive Order S-14-08: SB 1078 (Chapter 516, Statutes of 2002) requires retail sellers of electricity, including investor-owned utilities and community choice aggregators, to provide at least 20 percent of their supply from renewable sources by 2017. SB 107 (Chapter 464, Statutes of 2006) changed the target date to 2010. In November 2008, Governor Schwarzenegger signed Executive Order S-14-08, which expands the state’s Renewable Energy Standard to 33 percent renewable power by 2020.

Senate Bill 350: This bill requires that the amount of electricity generated and sold to retail customers per year from eligible renewable energy resources be increased to 50 percent by December 31, 2030, as provided. The bill also makes other revisions to the Renewable Portfolio Standard (RPS) Program and to certain other requirements on public utilities and publicly owned electric utilities. This bill would require the State Energy Resources Conservation and Development Commission to establish annual targets for statewide energy efficiency savings and demand reduction that will achieve a cumulative doubling of statewide energy efficiency savings in electricity and natural gas final end uses of retail customers by January 1, 2030. The bill would require the PUC to establish efficiency targets for electrical and gas corporations consistent with this goal. The bill would require local publicly owned electric utilities to establish annual targets for energy efficiency savings and demand reduction consistent with this goal.

SB 1122 The CA Public Utilities Commission BioMAT Program: This bill was passed based on the recognition that California is missing out on the carbon reduction benefits of using organic waste for conversion to energy and, in this case, electricity. The bill directs electrical

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 corporations subject to the RPS Program described above to collectively procure at least 250 megawatts of electricity from developers of bioenergy projects that commence operation on or after June 1, 2013. The bill requires the commission to allocate those 250 megawatts to electrical corporations from specified categories of bioenergy project types, with 50 megawatts specifically allocated to forest biomass projects such as the project described. The program developed for this procurement requirement will commence in February of 2015. It is the intent of this project to procure a Power Purchase Agreement under this program.

SB 605 Short-Lived Climate Pollutants: This Bill passed in 2014 requires the CARB to complete an inventory of sources and emissions of short-lived climate pollutants in the state based on available data, identify research needs to address any data gaps, identify existing and potential new control measures to reduce emissions, and prioritize the development of new measures for short-lived climate pollutants that offer co-benefits by improving water quality or reducing other air pollutants that impact community health and benefit disadvantaged communities, as identified pursuant to Section 39711. The Board is also required to coordinate with other state agencies and districts to develop measures identified as part of the comprehensive strategy. Black carbon is one of the significant short-lived climate pollutants that is considered within this Plan. Black carbon is produced in large amounts when wildfire occur or when woody biomass is open pile burned. This project’s processing of wood that would have otherwise been burned relates to and supports the Plan concepts developed by CARB.

Greenhouse Gas Cap and Trade Program: California’s GHG cap and trade program is the central element of AB 32 and covers major sources of GHG emissions in the state such as refineries, power plants, industrial facilities, and transportation fuels. The regulation includes a GHG cap that will decline over time. CARB distributes allowances, which are tradable permits, equal to the emission allowed under the cap. The final cap and trade regulations were adopted in 2011.

The regulation sets a statewide limit on sources and establishes a financial incentive to drive long-term investment in cleaner fuels and more efficient uses of energy. Companies are not given a specific limit on their GHG emissions but must supply a sufficient number of allowances (each equivalent to one ton of CO2) to cover their annual emissions. As the cap declines each year, the total number of allowances in the state drops which requires companies to find the most cost-effective approach to reducing their emissions.

Those sources that need additional allowances to cover their emissions can purchase them at quarterly auctions by CARB, or buy them on the market from sources that have excess allowances.

The final regulations for the cap and trade program are codified in Subchapter 10 Climate Change, Article 5, Sections 95800 to 96023, Title 17, California Code of Regulations. Section 95802(a)(31) contains a definition of “biomass” as defined in the cap and trade regulations: “Biomass means non-fossilized and biodegradable organic material originating from plants, animals, and microorganisms, including products, by-products, residues, and waste from

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 agriculture, forestry, and related industries as well as the non-fossilized and biodegradable organic fractions of industrial and municipal wastes, including gases and liquids recovered from the decomposition of non-fossilized and biodegradable organic material. For the purpose of this article, biomass includes both California Renewable Portfolio Standard (RPS) eligible and non-eligible biomass as defined by the California Energy Commission.”

Section 95852.2 identifies emissions without a compliance obligation under the cap and trade program. As stated in Section 95852.2:

Emissions from the following source categories and from the combustion of the following fuel types count toward applicable reporting thresholds, as applicable in MRR (Mandatory Reporting Regulation), but do not count toward a covered entity’s compliance obligation set forth in this article unless those emissions are reported as non-exempt biomass- derived CO2 under MRR. Emissions without a compliance obligation include: (a) CO2 emissions from combustion of the following biomass-derived fuels: (1) The biogenic fraction of solid waste materials as reported under MRR; (2) Waste pallets, crates, dunnage, manufacturing and construction wood wastes, tree trimmings, mill residues, and range land maintenance residues; (3) All agricultural crops or waste; (4) Wood and wood wastes identified to follow all of the following practices: (A) Harvested pursuant to an approved timber management plan prepared in accordance with the Z’berg-Nejedly Forest Practice Act of 1973 or other locally or nationally approved plan; and (B) Harvested for the purpose of forest fire fuel reduction or forest stand improvement

The proposed project would utilize fuel that fully meets the definition of biomass and, as such, per the requirements of Section 95852.2, the proposed project would be required to report GHG emissions under the MRR; however, GHG emissions from the project would not count towards the compliance obligations under the cap and trade program. In other words, the GHG emissions from the combustion of biomass fuels for electricity generation are not required to be offset or reduced under the cap and trade program as they are seen as replacing or avoiding the use of fossil fuels in the production of the electricity generated.

1.7.3 Thresholds of Significance under CEQA

As described previously, the State Legislature and the global scientific community have found that global climate change poses significant adverse effects to the environment. Per Appendix G of the CEQA Guidelines, climate change-related impacts are considered significant if implementation of the proposed project under consideration would do any of the following:

1. Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment. 2. Conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of greenhouse gases. 32

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Few public agencies in California have adopted GHG thresholds of significance for CEQA, and no GHG thresholds have been developed specifically for facilities that generate electricity. Neither Mariposa County Air Pollution Control District nor Mariposa County has developed GHG CEQA thresholds.

CARB’s 25,000 metric ton/year threshold is a reporting threshold for the cap and trade program, and was not specifically established as a CEQA threshold for GHGs. However, in the report titled: CEQA and Climate Change: Evaluating and Addressing Greenhouse Gas Emissions from Projects Subject to the California Environmental Quality Act, the California Air Pollution Control Officers Association (CAPCOA) identifies the 25,000 metric ton threshold, as used by CARB for their reporting threshold, as a potential and appropriate non-zero GHG threshold for use in a CEQA document (see pages 44-45 of the above-referenced 2008 report).

Additionally, the U.S. EPA regulations for reporting of GHG emissions set a 25,000 metric ton threshold for large emission sources and the European Union has provided for “small installations” with emissions under 25,000 metric tons to be exempted from its Emissions Trading Scheme; notably, biomass emissions are excluded from this calculation.

In summary, a 25,000 metric ton threshold has been determined in several state, federal, and international rulemaking processes to represent a significant level of emissions with respect to cumulative contributions to global climate change. Given the research and resources that went into the development of the GHG Mandatory Reporting Rule and cap and trade programs adopted by CARB, the U.S. EPA GHG reporting rule, and the fact that the 25,000 metric ton threshold would capture approximately 94 percent of GHG emissions associated with stationary sources in California (CAPCOA, page 44), County has used the 25,000 metric tons/year of CO2e threshold in past projects, and chooses to do so for this project.

Therefore, if the proposed project generates 25,000 metric tons of CO2e or greater in a year, it would be considered to have a significant and cumulatively considerable impact on the environment. If the proposed project would generate less than 25,000 metric tons of CO2e per year, it would be considered a less than significant and less than cumulatively considerable impact related to climate change and GHGs. In order to determine if the proposed project would conflict with an applicable plan, policy, or regulation adopted for the purpose of reducing the emissions of GHGs, the proposed project is compared to the most applicable and relevant state-level regulations adopted to reduce GHG levels. GHG emissions for the project are covered in the last Section of the Air Study, Attachment I.

1.8 Hazardous Materials

Flammable or Hazardous Liquids

A hazardous material is defined in Title 22 of the California Code of Regulations (CCR) as follows:

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

“A substance or combination of substances which, because of its quantity, concentration, or physical, chemical or infectious characteristics, may either (1) cause, or significantly contribute to, an increase in mortality or an increase in serious, irreversible, or incapacitating reversible, illness; or (2) pose a substantial present or potential hazard to human health or environment when improperly treated, stored, transported or disposed of or otherwise managed” (CCR, Title 22, Section 66260.10).

Hazardous materials are defined as substances with certain chemical and physical properties that could pose a substantial present or future hazard to human health or the environment if improperly handled, stored, disposed or otherwise managed. Public health hazards from hazardous materials may occur through contamination of soils or groundwater or through airborne releases of vapors, fumes, or dust. Exposure to hazardous materials and wastes could cause various short-term or long-term health effects. The health effects would be specific to each substance or combination of substances. There are several materials that will be stored on site consistent with state law which are discussed within the Checklist below.

Airport Proximity The location for the proposed Mariposa Biomass Facility is 1.2 miles from the Mariposa- Yosemite Airport and therefore falls into the Mariposa-Yosemite Airport Influence Area. In order to project public safety, the County has established a number of land use standards that include the height of structures located in the influence area. In order clearly describe the height requirements in these standards, a series of imaginary surfaces define the protected airspace that airplanes use when taking off or landing. These surfaces are shown in the figure found within the Hazards Discussion Section below and in Attachment F. Airplanes taking off or landing are expected to stay above these surfaces and ideally structures, trees and terrain will be below the surfaces. Given the nature of the terrain near the airport, e.g Mt. Bullion, there are obvious exceptions to this rule.

From a land use planning point of view, structures below these surfaces meet requirements and that is the case with the structures associated with the proposed Biomass Project facility which are 78 feet below the conical surface (approach to airport). The tallest facility structure is the air exhaust stack at final elevation of 2454 feet. The maximum allowable would be at 2532 elevation, being the conical surface location directly above the air stack location. To determine the exact location of exhaust stack under the imaginary conical surface and whether or not it will penetrate the conical surface, an evaluation was conducted that applied the methodology prescribed by the Airport Overlay District and Airport Plan documents. The objective of the evaluation is to insure that the proposed project air exhaust stack height (elevation) does not penetrate the conical surface. The conical surface rises with a 20:1 slope or 1 foot vertically for every 20 feet of horizontal distance over the ground from the nearest end of the airport runway. More specifics about what these surface calculations mean as they affect determining building and utility structure height is discussed in the Hazards Section below. Additionally an evaluation of the air exhaust stack plume was conducted and included in Attachment F. The project will notify the FAA of our new facility as it is in the Airport Influence areas.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

1.9 Hydrology / Water Quality

1.9.1 General

The western portion of the County is relatively flat, with gently rolling hills that gradually increase toward the east. Moving eastward, the hills become more pronounced and the elevation quickly rises and falls through mountains and valleys. The elevation begins around 300 feet in the west and rises to nearly 11,000 feet in the east. Most inhabited regions are below 5,000 feet.

Precipitation varies between the lower elevations in the western and southern portions of the County and the higher elevations in the eastern and northern portions of the County. Average precipitation ranges from about 15 inches annually in the lower elevations to about 50 inches at the higher elevations. Most of the annual precipitation falls between November and late April. Precipitation at the lower elevations occurs mainly in the form of rainfall with snowfall becoming the dominant form at the higher elevations. Melting of the winter snowpack at the higher elevations becomes the major source of runoff to the Merced River during the spring and summer months.

There are three major drainage basins in Mariposa County: the Merced River, Chowchilla/Fresno River, and a localized cluster of streams of the east valley known as the Lower Mariposa group of streams. These three basins and their component watersheds are part of the much larger San Joaquin River system that drains the western slopes of the Sierra Nevada. The proposed Project area is located within the Lower Mariposa group of streams drainage basin, approximately 1.5 miles west of Mariposa Creek and 0.5 mile east of Agua Fria Creek, the two creeks that drain the largest area of this stream group.

1.9.2 Water Supply

Water will be supplied to the project from an existing community well on parcel 1. The well’s capacity at the time of initial operation was 20 gpm. The well serves parcels 1 through 4. The project will use an average of 1.5 gpm of well water in the production of the syngas that fuels the gas engine generators to produce electricity. The project will include a condensate recycle system to collect the moisture that evaporates off the wood during the integral drying stage and thus minimize the water usage at the facility. Water usage at the facility is expected to be ≤ 2160 (1.5x60x24) gallons per day. A recent well test, report (No. 0930872) for the subject well indicates that it is 200 feet deep and taps four water-producing fractured quartz zones between 75 and 160 feet in depth. The well was constructed in March 2007 by Mariposa Well Drilling Co., Inc. On March 17, 2017, the static water level was 15 feet deep and the yield was 15 gpm after two hours of airlifting (limited by the pump installed in the well at the completion of the initial testing). Pursuant to the hydrologist recommendations, Mariposa Well Drilling Co., Inc. conducted a six-hour constant discharge on the well on September 27, 2017. The static water level was 29 feet deep, and was expected to be deeper than the earlier measurement, which was made in the spring, when water

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 levels are normally shallower. The well was pumped at an average rate of 15 gpm. At the end of the pumping period, the pumping level was 76 feet. The drawdown was 47 feet and the specific capacity was 0.3 gpm per foot. This supports the use of the well for all uses at the facility without causing significant drawdown. Copies of the Hydrology and pump test measurements that are the basis of the information in this Section can be found within Attachment M. 1.10 Land Use / Planning The project is located within the Mariposa Industrial Park as approved by the County under Ordinance 696 creating a Planned Development Zone (PDZ 87-1). The property is zoned for industrial use and PDZ 87-1 governs the development standards. The property is also subject to the Mariposa Yosemite Airport Land use Plan and the Mariposa Yosemite Airport Master Plan, as well as the Airport Overlay Zoning designation found at 17.64.010 of the County Zoning Code.

1.11 Mineral Resources Environmental Setting

The early mineral history of Mariposa County begins primarily with the discovery of gold and the development of mining in the region. Placer gold was initially discovered in the County sometime prior to 1849, resulting in one of the biggest gold rushes in history. A large portion of the gold mined in California was found along Highway 49 near Mariposa. Agua Fria and Mariposa were among the first placer deposits to be worked in the County. During the 1850’s, several rich quartz veins were discovered in the mountains near Bear Valley and Hornitos. The mineral resources of Mariposa County have been an integral part of the County’s history and have been an economic asset to the region and the State. The mineral deposits in Mariposa County are located mainly along the gold rush belt. This belt, commonly called the "Mother Lode", stretches through the Sierra Nevada foothills for about 150 miles, extending north and northwest from the vicinity of Mariposa through Tuolumne, Calaveras, Amador, El Dorado, Placer, and Nevada counties. (Britannica, 1999).

Although historically gold has been the most predominant mineral in the area, many other ore deposits are located in parallel formations to the east and west of the main "Mother Lode" fault system. According to the Development Constraints Report, substantial quantities of copper, lead, zinc, silver and tungsten have been mined in the County. Nonmetallic minerals have also be found, including barite, limestone, dolomite, mica, schist, slate, granite, silica, and sand and gravel.

1.12 Noise 1.12.1 Regulatory Setting

Mariposa County General Plan

In California, cities and counties are required to adopt a Noise Element as part of their General Plan. Cities and counties can also adopt noise control requirements within their zoning

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 ordinances or as a separate noise ordinance. The project site is located in Mariposa County, which has a General Plan Noise Element but does not have a Noise Ordinance.

Chapter 15 of the Mariposa County General Plan contains the County’s Noise Element. The Noise Element contains adopted goals, policies and implementation measures pertaining to noise. However, the General Plan Noise Standards do not provide numeric target levels for use in assessing the noise impacts of this project. The County’s Noise Element goals, policies and implementation measures are reproduced below:

Goal 15-1: Preserve the quality of life in Mariposa County by controlling noise at its source.

Policy 15.1a: Control noise at its source.

Goal 15-2: Protect County residents from the harmful and annoying effects of exposure to excessive noise.

Policy 15-2a: Siting and construction of facilities intended for noise sensitive uses shall comply with the noise reduction standards of applicable State building codes.

Policy 15-2b: New projects with extensive noise potential shall incorporate mitigation measures.

Policy 15-2c: Ensure that new development does not produce noise levels that create an unacceptable noise environment in those existing areas of the County where the noise environment is deemed acceptable, and also in those locations deemed noise sensitive.

1.12.2 Development Requirements for the Mariposa Industrial Park- PDZ 87-1

Section VII of the development standards found within the PDZ 87-1 pertain to “Activity Standards”, which include the specific standard applicable to permissible noise generation within the industrial park is provided below:

“Within the Mariposa Industrial Park the following regulations, regarding the production or generation of sound, shall apply:

1. Noise levels at any interior property line shall not exceed the 70 dBA level. 2. Noise levels at the boundary of State Highway 49 North shall not exceed the 55 dBA Level. 3. Noise levels at all other exterior boundaries of the Mariposa Industrial Park shall not exceed the 70 dBA level.”

1.12.3 Criteria for Project-Related Noise Level Increases

It is generally recognized that an increase of at least 3 dB for similar noise sources is usually required before most people will perceive a change in noise levels, and an increase of 6 dB is

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 required before the change will be clearly noticeable (Egan, Architectural Acoustics, page 21, 1988, McGraw Hill).

The Federal Interagency Commission on Noise (FICON) has developed a graduated scale for use in the assessment of project-related noise level increases. Table 3 was developed by FICON as a means of developing thresholds for impact identification for project-related noise level increases. The FICON standards have been used extensively in recent years by the authors of the supplied noise report in the preparation of the noise sections of Environmental Impact Reports that have been certified in many California Cities and Counties.

The rationale for the graduated scale used in the FICON standards is that test subjects’ reactions to increases in noise levels varied depending on the starting level of noise. Specifically, with lower ambient noise environments, such as those below 60 dB Ldn, a larger increase in noise levels was required to achieve a negative reaction than was necessary in more elevated noise environments.

The use of the FICON standards are considered conservative relative to thresholds used by other agencies in the State of California. For example, the California Department of Transportation (Caltrans) requires a project-related traffic noise level increase of 12 dB for a finding of significance, and the California Energy Commission (CEC) considers project-related noise level increases between 5-10 dB significant, depending on local factors. Therefore, the use of the FICON standards, which set the threshold for finding of significant noise impacts as low as 1.5 dB, provides a very conservative approach to impact assessment for this project.

Based on the FICON research shown in Table 3 of the Noise Study, a 5 dB increase in noise levels due to a project is required for a finding of significant noise impact where ambient noise levels without the project are less than 60 dB Ldn. Because ambient noise levels at the nearest residences to the project site were quantified as being below 60 dB Ldn, a 5 dB increase in average ambient noise levels is considered the threshold of significance for this project at the nearest residential receptors.

1.12.4 Noise Standards of Significance Applied to this Project

The following standards of significance, which are based on the California Environmental Quality Act Guidelines (State CEQA Guidelines) in conjunction with adopted local noise policy and appropriate noise standards as described above, are applied to this project:

a) Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies.

1. Pursuant to the Mariposa Industrial Park standards, noise levels from the project shall not exceed 70 dBA at the project site property line. 2. Pursuant to the Mariposa Industrial Park standards, noise levels from the project shall not exceed or 55 dBA at Highway 49.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

b) A substantial temporary or permanent increase in ambient noise levels in the project vicinity above levels existing without the project.

The Mariposa County General Plan Noise Element does not contain numeric noise standards. Therefore, this analysis utilizes the FICON methodology for establishing significance criteria. Based on the average noise measurement results shown in Table 1, it is clear that existing ambient conditions are well below 60 dB Ldn at the nearest residences to the project site. Therefore, the noise standards used to assess project noise impacts are ambient plus 5 dB according to the Noise Study Table 3 criteria.

Daytime ambient noise levels at the nearest residence to the project site were measured to be approximately 50 dB Leq and 67 dB Lmax. As a result, conservative daytime ambient noise level standards applied at the nearest residences to this project would be 55 dB Leq and 70 dB Lmax.

Nighttime ambient noise levels at the nearest residence to the project site were measured to be approximately 41 dB Leq and 60 dB Lmax. As a result, conservative nighttime ambient noise level standards applied to this project would be 45 dB Leq and 65 dB Lmax at those nearest residences.

Although the plant equipment would operate 24-hours per day, deliveries of biomass material and the transport of that material from the storage area to the plant equipment is proposed to be limited to daytime hours. As a result, noise impacts of the project are evaluated separately for both daytime and nighttime periods.

The Project’s noise impacts were considered within a study on the same, which can be found as Attachment N.

1.16 Transportation /Traffic

Traffic

The Project proposes to develop a small biomass plant on two parcels within the Mariposa Industrial Park. The plant would employ 8-10 full time staff and would primarily process woody biomass from nearby forest thinning activities that is currently being delivered to facilities farther away. An analysis was provided based on feedback from Caltrans staff, which is Attachment O, and the County, and road data collected that all can be found within a Traffic Study, found in Attachment P. The intersection of CA-49 and Mykle Oaks Road/Gold Leaf Drive currently serves as the primary access route to the Mariposa Industrial Park and Copper Leaf Lane. The Mariposa Industrial Park is located to the south of CA-49 midway between the Mariposa-Yosemite Airport to the west and CA-140 and the community of Mariposa to the east. Intersection operations were assessed for level of service and queuing with and without the proposed

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 project, and the intersection geometry was assessed for safety with the expected increase in truck traffic turning on and off of the highway. The project will process approximately 37 bone dry tons of biomass each day. Truck deliveries will be limited to 7 AM to 5 PM, six days per week. The bulk of the material will be delivered in 45 ft long, 100 cyd self-unloading (walking floor) chip trailers. These enclosed trailers have a conveying floor that automatically moves the woodchips out then back of the trailer. Each trailer can transport approximately 20 tons of woodchips (wet), which equates to about 12 tons (dry). The Project may accept woodchips from local chippers that would deliver chips in 8 cyd dump trucks. This would include suppliers such as the Fire Safe Council, Trees Inc., Goodman and Cole, etc. In all cases the wood material source of origin would need to be verified in order to be SB 1122 compliant as a renewable source. The project will require monthly deliveries of propane, nitrogen, diesel fuel and other operation and maintenance materials. The project will need to truck ash for disposal, which will average one truckload per week. The project estimates an average of 3 to 4 chip trailer deliveries per day in addition to 8 to 10 small dump truck deliveries per day. There are no plans to allow residential disposal of material at the facility. A complete traffic study was prepared by TKJM Consultants. The study concluded that the increased traffic will be insignificant. The study, however, recommended that the intersection of Gold Leaf Drive and Highway 49 be improved to provide a better turning radius for trucks exiting Highway 49 south bound onto Gold Leaf Drive. The project includes this improvement as a part of the project. Staffing/Parking The facility will operate 24 hours per day, seven days per week and will initially employ a fulltime staff of up to 10. This assumes 2 operators per 8 hour shift and 1 additional maintenance worker and 1 administrator. As operation experience is developed staffing requirements may be reduced to 6 or 7. During daytime hours, a maximum staff of 4 will be on site. A total of 5 parking spaces are proposed each 9 ft by 20 ft as indicated on the Preliminary Grading Plan (Attachment E). Regular public access is not anticipated.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

1.17 Utilities / Service Systems

Solid Waste: Non-hazardous Ash and Sludge 650 tons per year of ash is expected to be produced at the facility. According to the Cal Recycle, which governs all types of ash disposal from facilities that exclusively burn biomass materials, clean biomass does not normally trigger toxics issues. The Project will comply with all applicable air quality laws, rules, and regulations, and test its residue (ash) regularly, and if hazardous, sends that residue to a Class I hazardous waste facility. Also, burning other materials such as petroleum coke or natural gas to maintain a particular temperature level is permissible. Ash produced from forest waste is not expected to include any hazardous residue as defined under 22 CCR 66261.30. Additionally, the project will produce a water/sawdust/ash substance in the amount of about 60 pounds per day. Such material will not trigger hazardous waste classification under 22 CCR 66261.31 or 22 CCR 66261.32. A report produced by the technology provider, Cortus Energy, on the composition of the Sludge is found herein as Attachment Q. All ash and sludge will be disposed of at an appropriately permitted disposal facility.

2.0 DETERMINATION

On the basis of this initial evaluation:

I find that the proposed project COULD NOT have a significant effect on the ☐ environment, and a NEGATIVE DECLARATION will be prepared.

I find that although the proposed project could have a significant effect on the ☒ environment, there will not be a significant effect in this case because revisions in the project have been made by or agreed to by the project proponent. A subsequent MITIGATED NEGATIVE DECLARATION will be prepared.

I find that the proposed project MAY have a significant effect on the environment, ☐ and an ENVIRONMENTAL IMPACT REPORT is required.

I find that the proposed project MAY have a “potentially significant impact” or ☐ “potentially significant unless mitigated” impact on the environment, but at least one effect 1) has been adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has been addressed by mitigation measures based on the earlier analysis as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the effects that remain to be addressed.

I find that although the proposed project could have a significant effect on the ☐ environment, because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or mitigated pursuant to that earlier EIR or 41

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

NEGATIVE DECLARATION, including revisions or mitigation measures that are imposed upon the proposed project, nothing further is required.

By: Steve Engfer______

January 22, 2018 Signature Date

Associate Planner County of Mariposa Title

3.0 POTENTIALLY SIGNIFICANT EFFECTS CHECKLIST

A. Environmental Factors Potentially Affected

The environmental factors checked below would be potentially affected by this project, involving at least one impact that is a “Potentially Significant Impact” as indicated by the checklist on the following pages.

(blank): no impact L: Less than Significant Impact M: Less than Significant Impact with Mitigation PS: Potentially Significant

L Aesthetics L Agriculture/Forest Res. M Air Quality M Biological Resources L Cultural Resources L Geology/Soils L Greenhouse Gas L Hazards/Haz. L Hydrology/Water Emissions Materials Qual. Land Use/Planning Mineral Resources M Noise Population/Housing M Public Services L Recreation M Transportation/Traffic L Tribal Cultural M Utilities/Service Resources Systems L Mandatory Findings of Significance

B. Evaluation of Environmental Impacts:

1) A brief explanation is required for all answers except “No Impact” answers that are adequately supported by the information sources a lead agency cites in the parentheses following each question. A “No Impact” answer is adequately supported if the referenced information sources show that the impact simply does not apply to projects 42

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

like the one involved (e.g., the project falls outside a fault rupture zone). A “No Impact” answer should be explained where it is based on project-specific factors as well as general standards (e.g., the project will not expose sensitive receptors to pollutants, based on a project-specific screening analysis).

2) All answers must take account of the whole action involved, including off-site as well as on-site, cumulative as well as project-level, indirect as well as direct, and construction as well as operational impacts.

3) Once the lead agency has determined that a particular physical impact may occur, then the checklist answers must indicate whether the impact is potentially significant, less than significant with mitigation, or less than significant. “Potentially Significant Impact” is appropriate if there is substantial evidence that an effect may be significant. If there are one or more “Potentially Significant Impact” entries when the determination is made, an EIR is required.

4) “Negative Declaration: Less Than Significant With Mitigation Incorporated” applies where the incorporation of mitigation measures has reduced an effect from “Potentially Significant Impact” to a “Less Than Significant Impact.” The lead agency must describe the mitigation measures, and briefly explain how they reduce the effect to a less than significant level (mitigation measures from Section XVII, “Earlier Analyses,” may be cross-referenced).

5) Earlier analyses may be used where, pursuant to the tiering, program EIR, or other CEQA process, an effect has been adequately analyzed in an earlier EIR or negative declaration. Section 15063(c)(3)(D). In this case, a brief discussion should identify the following:

a) Earlier Analysis Used. Identify and state where they are available for review.

b) Impacts Adequately Addressed. Identify which effects from the above checklist were within the scope of and adequately analyzed in an earlier document pursuant to applicable legal standards, and state whether such effects were addressed by mitigation measures based on the earlier analysis.

c) Mitigation Measures. For effects that are “Less than Significant with Mitigation Measures Incorporated,” describe the mitigation measures which were incorporated or refined from the earlier document and the extent to which they address site-specific conditions for the project.

6) Lead agencies are encouraged to incorporate into the checklist references to information sources for potential impacts (e.g., general plans, zoning ordinances). Reference to a previously prepared or outside document should, where appropriate, include a reference to the page or pages where the statement is substantiated.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

7) Supporting Information Sources: A source list should be attached, and other sources used or individuals contacted should be cited in the discussion. See Section 5.

8) This is only a suggested form, and lead agencies are free to use different formats; however, lead agencies should normally address the questions from this checklist that are relevant to a project's environmental effects in whatever format is selected.

9) The explanation of each issue should identify:

a) The significance criteria or threshold, if any, used to evaluate each question; and b) The mitigation measure identified, if any, to reduce the impact too less than significance

4.0 ENVIRONMENTAL IMPACTS

Less Than

Significant Potentially Less Than with No Significant Significant Mitigation Impact Impact Impact Incorporati on

I. AESTHETICS -- Would the project: a) Have a substantial adverse effect on a ☐ ☐ ☐ ☒ scenic vista? b) Substantially damage scenic resources, including, but not limited to, ☐ ☐ ☐ ☒ trees, rock outcroppings, and historic buildings within a state scenic highway? c) Substantially degrade the existing visual character or quality of the site and ☐ ☐ ☒ ☐ its surroundings?

d) Create a new source of substantial light or glare which would adversely ☐ ☐ ☒ ☐ affect day or nighttime views in the area? Discussion

A significant impact would be one that substantially degrades the existing visible character or quality of the site and its surroundings. As stated in the LDA MND, “the Project does not directly impact site aesthetics, but there is an indirect impact will be the industrial buildings developed on the site. The county has not established building design or landscape requirements

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 for industrial development in this area; therefore, the threshold of impact is set quite high.” Based on this previously determined threshold and the specific attributes of the project, it is not expected to have any impacts. No mitigation is required because no actions beyond the application of existing regulations from the multiple plans and ordinances on the project are necessary. See photo depictions of the site within the Aesthetics Environmental Setting Section above, and more below. The project will have a less than significant impact on aesthetics. a) Have a substantial adverse effect on a scenic vista?

A significant impact would be one that has a substantially adverse effect on a scenic vista. There are no ordinances, policies, resolutions or other documents that identify designated scenic vistas at or near the project site. Based on the site visit, no extraordinary views exist. Thus, there are no impacts. b) Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway?

There are no designated scenic resources within the Property area, no historical buildings, and natural tree cover will be largely maintained, therefore there is no impact.

c) Substantially degrade the existing visual character or quality of the site and its surroundings?

As mentioned within the Discussion above, the threshold for triggering a visual significant impact in this area is high because the community has the expectation that the area is to be developed as an industrial park. Nevertheless, the project is taking all possible steps to mitigate the aesthetic impacts. First, the equipment will be painted an earth tone color to comply with PDZ 87-1, and will blend with the natural environment at the site, substantially minimizing glare and other visual impacts. The Project will comply with all landscaping and outdoor storage restrictions, fencing, and setbacks of 10 feet from the road and 12 feet from property line, as well as the advertising and sign requirements within PDZ 87-1. Most significantly, the PDZ 87-1 limits building heights for aesthetic purposes to 45 ft and utility structures to 75 ft. The tallest building on the site is the gasifier enclosure, which is 40 ft high. The tallest utility structures are the safety flare, 23 ft and the main air exhaust stack, which is 60 ft high, which is 15 feet lower than required under the PDZ-87-1 limitations.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Figure 7

Figure 8

As the photo simulations reflect, this is the view from the nearest home across the Highway. The building is completely out of view, with only a portion of the Utility Stack showing through the mature trees onsite, which provide substantial natural screening. From farther up the hill, the building can be seen but is still blends substantially with the view. The Project did consider shorter stack height, but the height of the stack is important in terms of dispersal of 46

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 potential air contaminants, and therefore cannot be any lower without potentially impacting public health. See more within the Air Quality Section for more about this topic. As stated on Page 16 of the Air Quality Report (Attachment I) the exhaust stack height was developed to protect public health and safety. Reducing the exhaust stack height from the proposed 60 feet could result in higher air dispersion modeled ground-level impacts due to a lower release height. In addition, lowering the exhaust stack height could result in building- induced downwash of the exhaust plume, which is caused by building or structures wake effect resulting in a downward trajectory winds in the project area. This downward wind trajectory causes the exhaust plume to also be directed downward, resulting in less plume dispersion and higher modeled ground-level concentrations. Therefore, on balance, the public health and safety needs for the proposed 60 feet height, will have some impact and will be nominally visible. Compliance with the requirements within the PDZ 87-1 will ensure that the facility is screened with natural, mature trees and painted subtle glare reducing tones. The safety flare pilot flame is another issue to discuss. It is shielded from view and will not be seen under normal operation. However, during plant startup, plant shutdown and during a safety situation that requires immediate shutdown of the gas engine generator, syngas will temporarily be bypassed through the safety flare and a flame will be visible on the top of the flare stack. Based on the analysis above, a less than significant impact is expected. d) Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area?

Glare The equipment will be painted an earth tone color to comply with PDZ 87-1, and will blend with the natural environment at the site, substantially minimizing glare. Lighting The project will operate 24 hours per day and will therefore, require safety lighting around the plant. The exact location and wattage of the lighting will not be known until the plant is designed in detail and drawings are submitted to the Building Department for review, but it will comply with all lighting requirements within the Industrial Zoning requirements, if any, as well as the PDZ 87-1, which requires that lighting be no more than 15 feet above the ground, it shall not be directed off premises or cause reflections into streets or roads as to cause a hazard. The Project will also comply with the Airport Overlay Zone, and more specifically, the federal rules relating to properties near airports that are referenced in that document. Lighting will also comply with International Dark Sky standards as required by the General Plan. Lighting around the plant will be shielded and directed downward to minimize any impact on the neighbors. Lighting which may be required for maintenance or repair of outdoor equipment 47

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 will only be turned on when necessary and only temporarily. Note that there will be no lighting installed within the wood chip storage area on Parcel 3. Compliance with all existing requirements within the County Code and the PDZ 87-1 will adequately manage lighting at the Project, therefore a less than significant impact is expected.

II. AGRICULTURE AND FORESTRY RESOURCES -- In determining whether impacts to agricultural resources are significant environmental effects, lead agencies may refer to the California Agricultural Land Evaluation and Site Assessment Model (1997) prepared by the California Dept. of Conservation as an optional model to use in assessing impacts on agriculture and farmland. In determining whether impacts to forest resources, including timberland, are significant environmental effects, lead agencies may refer to information compiled by the California Department of Forestry and Fire Protection regarding the state’s inventory of forest land, including the Forest and Range Assessment Project and the Forest Legacy Assessment project; and forest carbon measurement methodology provided in Forest Protocols adopted by the California Air Resources Board. Would the project: Less Than Less Potentiall Significant Than y with No Significa Significa Mitigation Impact nt nt Impact Incorporati Impact on a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland ☐ ☐ ☐ ☒ Mapping and Monitoring Program of the California Resources Agency, to non- agricultural use? b) Conflict with existing zoning for agricultural use, or a Williamson Act ☐ ☐ ☐ ☒ contract? c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code section 12220(g)), timberland (as defined by Public Resources ☐ ☐ ☐ ☒ Code section 4526), or timberland zoned Timberland Production (as defined by Government Code section 51104(g))? d) Result in loss of forest land or ☐ ☐ ☐ ☒ conversion of forest land to non-forest use? e) Involve other changes in the existing ☐ ☐ ☐ ☒ 48

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 environment which, due to their location or nature that could result in conversion of Farmland, to non-agricultural use?

Discussion

Based on the extensive discussion above in the existing environmental and regulatory section covering Forestry issues, the Project is one that will have a positive impact on forestry resources in the County. The Project does not impact agricultural resources. a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? There is no such land within the area of the Project, therefore there is no impact. b) Conflict with existing zoning for agricultural use, or a Williamson Act contract? There is no such land within the area of the Project, therefore there is no impact. c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code section 12220(g)), timberland (as defined by Public Resources Code section 4526), or timberland zoned Timberland Production (as defined by Government Code section 51104(g))?

This Project will not have an impact on TPZ zoned property, other than minimal impacts of reducing costs of upkeep for these properties as they will have a location to haul their woody biomass waste from thinning treatments to the facility for disposal. No impact on TPZ or Forest land is expected. d) Result in loss of forest land or conversion of forest land to non-forest use?

This Project will be obtaining a Power Purchase Agreement that will be regulated by the SB 1122 Program’s feedstock requirements as discussed above in the Regulatory Setting. These requirements ensure that that wood used at these facilities is truly waste wood that has not been grown for the purposes of energy production. Additionally, while the PPA prices for electricity are high, the economics of the value of large diameter commercially viable wood for wood products highly outweighs the use of wood for electricity in California, so it is not expected that this project will trigger commercial wood harvests. This Project will not result in loss or conversion of forest land; there is no impact. e) Involve other changes in the existing environment which, due to their location or nature that could result in conversion of Farmland, to non-agricultural use? There is no such land within the area of the Project, therefore there is no impact.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

III. AIR QUALITY -- Where available, the significance criteria established by the applicable air quality management or air pollution control district may be relied upon to make the following determinations. Would the project:

Less Than Significant Potentially Less Than with No Significant Significan Mitigation Impact Impact t Impact Incorporati on a) Conflict with or obstruct implementation of the applicable air ☐ ☐ ☒ ☐ quality plan? b) Violate any air quality standard or contribute substantially to an existing or ☐ ☐ ☒ ☐ projected air quality violation? c) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is nonattainment under an applicable federal or ☐ ☐ ☒ ☐ state ambient air quality standard (including releasing emissions, which exceed quantitative thresholds for ozone precursors)? d) Expose sensitive receptors to ☐ ☐ ☒ ☐ substantial pollutant concentrations? e) Create objectionable odors affecting a ☐ ☒ ☐ ☐ substantial number of people?

Discussion

The potential air emissions of the proposed 2.4-MW net (2.7 MW gross) woody biomass gasification to electricity facility are presented and discussed below taking into account the Mariposa County Air Pollution Control District thresholds and regulations, as well as state and federal law as that relates to air quality.

a) Conflict with or obstruct implementation of the applicable air quality plan? b) Violate any air quality standard or contribute substantially to an existing or projected air quality violation?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

c) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including releasing emissions, which exceed quantitative thresholds for ozone precursors)? Based on the application of the District’s thresholds and the conclusion of the air study, there will not be any cumulatively considerable increase of criteria pollutants.

Answer questions a,b,c:

Projected Emissions – Stationary Sources

The proposed bioenergy facility will utilize approximately 12,000 bone dry tons (BDT) of woody biomass waste per year. Total electrical production will be 2.7 MW gross, with 2.4 MW net transmitted to the grid. As the proposed project will sell electrical power to Pacific Gas & Electric under the California Bioenergy Market Adjustment Tariff (BioMAT) Category 3, 80% of the woody biomass waste will originate from forest sources, much of which would have been otherwise piled and burned.

The facility is planned to operate 24/7, however given there will be scheduled and unscheduled maintenance requirements for the equipment it is anticipated that the bioenergy facility will likely only operate approximately 330 days per year.

The proposed facility will utilize the Cortus Energy WoodRoll woody biomass gasification to electricity technology (see Figure 1 below) The facility includes a fuel drier, which removes moisture from the fuel before it enters the pyrolizer. Char produced by the pyrolizer is indirectly heated using the gases generated in the pyrolysis process and mixed with steam to produce a low nitrogen syngas. The syngas is to be combusted in two GE Jenbacher, type 6 gas engine generators to produce electricity (see Appendix A for engine specifications). The engines are equipped with SCRs for NOx control and CO catalysts for increased CO emission reduction. Particulate Matter will be controlled by filters (syngas filter and pyrolysis gas exhaust filter). The exhaust gas from the two engines as well as the exhaust from the fuel drier is ducted to one common stack. The facility also includes a flare to burn excess fuel during startup, shutdown and emergency upset conditions.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

A summary table of stationary emissions is presented below in Table C Total emissions are presented in tons per year (TPY) based on 8,760 annual hours. Table C (Table 1. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 1. Stationary Source Emission Estimates

Major MC Total Sourc APCD for e and IC Engine* WoodRoll** Flare*** CEQA 2.4 ERC Thres- MW Thres- hold hold

Emission Total Emission Total Emission Total Factor Emissions Factor Emissions Factor Emissions

(lb/hr) TPY (lb/hr) TPY (lb/hr) TPY TPY TPY TPY VOC 1.12 4.90 0.05 0.20 0.003 0.002 5.80 100 100 11.9 NOx 1.67 7.30 0.71 3.10 0.133 0.100 100 100 3 27.9 CO 5.55 24.30 0.07 0.30 0.027 0.020 100 100 6 PM10 0.23 1.00 0.07 0.30 0.000 0.000 1.48 100 100 PM2. 0.23 1.00 0.07 0.30 0.000 0.000 1.48 100 100 5 SOx 0.43 1.90 0.48 2.10 0.000 0.000 4.55 100 100

*- IC Engine emission factors from Manufacturer's (GE Jenbacher specifications w/SCR control device and catalytic converter ** - WoodRoll emissions factors based on measurements conducted by Cortus Energy *** - Emergency/standby flare emissions factors from Cortus Energy based on ordinary LPG/Propane burner

CalEEMod Modeling for Project Emissions

Emissions modeling for this project was performed using California Emission Estimator Model (CalEEMod) Version 2016.3.1. Project specific data was applied when available and remaining data was populated with Mariposa County APCD default data. Construction is not expected to occur during every day during the construction schedule, therefore, two model runs were performed, one with the actual as expected construction schedule for the worst-case daily emissions and one model containing a condensed single year construction schedule to represent the worst-case annual emissions. A condensed construction schedule was used to more accurately calculate annual emissions by basing the construction schedule on the number of working days. For example, if a construction phase was expected to range three months and only have 20 days of construction activity, it would be modeled in the condensed schedule version as a single month to account for a total of 20 working days instead of the CalEEMod auto calculated 60 days.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Project Emissions - Construction

The construction of the bioenergy facility will include the erection of an enclosed warehouse- type building, road construction, and site grading. There is expected to be no demolition of buildings or related structures as none currently exist onsite.

Project construction is assumed by the developer to take 9 months with approximately 2.4 acres of disturbed ground area. Grading/site preparation will utilize 1 each heavy wheel loader, hydraulic excavator, grader, material handling crane, and dump truck. Table 2 presents the maximum daily and annual construction emissions.

Table D (Table 2. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 2. Construction Emissions Estimates

Maximum Controlled Maximum Pollutant Daily Emissions Controlled Annual (lb/day) Emissions (tons) VOC 15.79 0.61 NOx 45.34 1.22 CO 99.01 2.38 SOx 0.16 0.004

PM10 10.77 0.27 PM2.5 4.21 0.11 1 CO2e 15,900 360.54 1 Annual CO2e is in metric tons per year.

These results of the CalEEMod modeling are found in Appendix B. Daily emissions from Section 2.1 of Daily Emissions Modeling Spreadsheet and Annual emissions from Section 2.1 of Annual Emissions Modeling Spreadsheet.

Project Emissions – Mobile and Temporary Sources

Mobile emission sources for the proposed bioenergy facility operation include truck activity (for chip delivery), loader activity (to move onsite biomass), employee commute trips, biomass hauling, and ash hauling. The front loader will operate onsite moving biomass from the storage windrows to the dryer’s feedstock hopper and stacking the storage windrows during and after feedstock delivery. Truck activity will follow the all-weather access roads onsite to reach the storage windrows. The scale is onsite and immediately adjacent to the bioenergy facility.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

The following CalEEMod inputs were used to estimate the operational mobile source emissions. ● 10 full-time employees with 10 round trips for a per day commute at an average 60 miles round trip; ● 12 additional jobs for recovering biomass with 12 round trips per day at an average 60 miles round trip ● Woody biomass fuel vehicles (i.e. chip vans) with a haul capacity of 12.5 BDT per load with 960 loads annually for 12,000 BDT of delivered biomass. Assume average 60 mile round-trip for feedstock acquisition: ● Ash removal, 650 tons per year (one 12.5 ton truckload per week), assume 2 mile round trip to nearby Mariposa County Landfill and Recycling Center.

The result of the operational mobile and temporary source emissions are presented in Table E.

Table E (Table 3. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 3. Operational Mobile and Temporary Source Emission Estimates

Maximum Maximum Pollutant Controlled Controlled Daily Annual Emissions Emissions (lb/day) (tons) VOC 3.03 0.48 NOx 19.30 3.00 CO 43.11 6.89 SOx 0.07 0.01

PM10 5.77 0.91

PM2 5 2.05 0.32 * CO2e 7,112 1054.57

* Annual CO2e is in metric tons per year.

These results of the CalEEMod modeling are found in Appendix B. Daily emissions from Section 4.1 of Daily Emissions Modeling Spreadsheet and Annual emissions from Section 4.1 of Annual Emissions Modeling Spreadsheet.

MCAPCD Significance Thresholds and Potential to Emit

The MCAPCD has not formally adopted thresholds of significant impact for the purposes of CEQA review. Thresholds of potential significant impact were nonetheless identified in the 2006 Final Environmental Impact Report prepared for the Mariposa County General Plan. In Table 4.8-1 of the Final EIR1, the emissions in excess of 100 TPY of any criteria air

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 contaminant would be the threshold for significant impact. In addition, the values listed in Table 4 were further confirmed by the MCAPCD2.

Table F (Table 4. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 4. MCAPCD Significance Thresholds

Project NOx VOC CO SOx PM10 PM2.5 Phase (ROG)

Operational 100 TPY 100 TPY 100 100 100 TPY 100 TPY TPY TPY Construction 100 TPY 100 TPY 100 100 100 TPY 100 TPY TPY TPY

Pre-Project Potential to Emit

The potential to emit before the implementation of the proposed project is from the disposal method of the sustainably sourced forest woody biomass feedstock. Emissions factors for biomass feedstock fated to the pile and burn scenario are based on a study by the National Renewable Energy Laboratory (NREL). These emission factors are verified in a technical paper by the Placer County Air Pollution Control District in 20114. The results of these studies are shown in Table 5 include the emissions from processing and transportation of the woody biomass feedstock

Table G (Table 5. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 5. Pile and Burn Emission Factors

Pollutant EF (lb/thousand BDT) VOC 24,000 NOx 2,500 CO 150,000 SOx 150 PM10 15,000

Net Potential to Emit

The factors in Table 5 are then utilized in Table 6 (along with results in Tables 1 and 3) below to determine the emissions from the standard practice of pile and burn of the woody biomass waste in the forest, which release uncontrolled emissions. The amount of forest-sourced woody 55

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018 biomass to be used (no less than 80% of the annual 12,000 BDT as required by BioMAT) and assuming 60% of that material would have been piled and burned is then calculated and compared to the operational and construction emissions in Tables 1, 2, and 3. The difference between the pile and burn and the operational/construction emissions can then be compared to the MCAPCD thresholds of significance (Table 4).

The net emissions based on the project represent the difference between the pre-project potential to emit and the project’s potential to emit, as shown in Table 6.

Table H (Table 6. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 6. Net Operational Emissions from Proposed Project

Amount of Estimate Percentage fuel Emission TPY for Amount of Percentage controller of fuel diverted factor for pile and fuel per forest emission Pollutant diverted from pile pile and burn year in sourced in TPY from pile and burn in BDT fuel (from and burn burning lb/BDT Table 1) in BDT NOx 12,000 80% 60.0% 5,760 7 20.16 11.93 PM10 12,000 80% 60.0% 5,760 15 43.20 1.48 VOC 12,000 80% 60.0% 5,760 24 69.12 5.8 CO 12,000 80% 60.0% 5,760 150 432.00 27.96 SOx 12,000 80% 60.0% 5,760 0.15 0.43 4.55

As can be seen in Table 6 above, the differentials between pile and burn emissions and the emissions from operations and construction are considerable, and place all the net emissions significantly below the MCAPCD significance thresholds.

It should be noted that this net emissions analysis does not exempt the facility from acquiring an Authority to Construct permit in which the diversion of the emissions from pile and burn will not be considered.

Calculation of the Pile and Burn Diversion Rate

In August 2015 TSS completed a biomass feedstock availability analysis for the Mariposa Biomass project, on behalf of the Mariposa County Fire Safe Council, which is included herein as Attachment R. Analysis and information in that analysis served as a basis for the diversion rate determination

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Optimized Feedstock Blend

The August 2015 feedstock supply availability analysis report included an optimized feedstock blend forecast:

Table I (Table 7. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 7: Optimized Feedstock Blend

Volume Percent Of Source (BDT/Yr) Total Forest 12,800 80% Urban 2,400 15% Agriculture 800 5% TOTALS 16,000 100%

Feedstock Procurement Forecast

It was TSS understanding that the Mariposa Biomass facility is expected to enter commercial service Q2 2020. Table J displayed below is a fuel procurement forecast by fuel type for the facility’s initial year of commercial operation (Q2 2020 to Q2 2021).

Table J (Table 8. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 8:Year One Feedstock Procurement Forecast

Volume Fuel Type (BDT/Yr) Usual Fate Timber Harvest Residuals 6,800 Open Burn 40% Open Burn/60% Hazardous Fuels Removal 6,400 chip/scatter Total Forest 13,200 Ag Fuel - Orchard Removal 600 Open Burn Urban Wood Waste 2,200 Landfill Total Feedstock Procured 16,000 Volume Diverted Away From Open Burn 9,960 Percent Diverted From Open Burn 62%

TSS conducted interviews with foresters that are familiar with forest practices in the Mariposa/Madera County region in order to generate this feedstock forecast. Information provided by these local foresters included:

● Historic timber harvest residual disposal methods. ● Current fuels treatment methodologies and disposal options. 57

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

● Planned tree mortality mitigation plans.

In addition, TSS utilized past experience as a forester and fuel procurement manager, and knowledge of current forest and agricultural management practices to generate this forecast. To increase the conservative nature of the emissions analysis, a diversion rate of 60% was used in Table H, and explained in more detail within Attachment R, the Biomass Feedstock Assesment.

Based on the fact that the 100 TPY threshold and the project’s emissions, this project would not have a significant impact on the environment. Then to add in the open burn pile diversion, it is clear that a less than significant impact is expected. d. Expose Sensitive Receptors to significant concentrations of air pollution?

Health Risk Assessment Dispersion Model Selection The health risk assessment (HRA) modeling for the project operations was conducted using the California Air Resources Board (ARB) Hotspots Analysis Reporting Program Version 2 (HARP 2) and the state-approved air dispersion modeling program AERMOD based on guidance and data from the California Office of Environmental Health Hazard Assessment (OEHHA) guidelines (OEHHA, 2015). The technical options selected for dispersion modeling include:

 Regulatory default control options  Rural dispersion mode  Receptor elevations and controlling hill heights obtained from AERMAP (version 11103 or most recent) output

Source Characterization

The facility sources including two syngas-fueled internal combustion engines and the Wood Roll process are vented through a single common facility stack and were therefore modeled as a single point source. Emissions for each source were combined with the exhaust parameters obtained from manufacturer data. A table of the facility stack parameters is presented in Table 9 below and emissions are presented in Appendix C.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Table K (Table 9. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Table 9. Modeling Parameters

Stack Height (m) 18.29 Stack Diameter (m)* 1.0 Exhaust Gas Flow Rate (m3/hr)** 17,145.4 Exhaust Velocity (m/sec) 6.06 Exhaust Temperature (deg. C)*** 220 * Stack diameter represents the inner diameter of the facility stack. ** Exhaust gas flow rate represents the manufacturer supplied flow rate multiplied by two to account for both engines exhausting through a common stack. ***Exhaust temperature accounts for heat recovery processes from exhaust stream resulting in a lower exhaust temperature.

Meteorological Data

Preprocessed meteorological data for input into AERMOD was obtained from the San Joaquin Valley Air Pollution Control District website for the Madera station (Station ID: 93242) located approximately 36 miles south of the site. This meteorological data site was selected as representative due to the following reasons: proximity to the proposed project, similar local land cover area to the proposed project area, and minimal terrain between the proposed project and selected meteorological station.

Receptor Selection

The receptor grid modeled in this risk analysis includes fence line receptors, sensitive receptors, census centroid receptors, and gridded receptors. The receptors were spaced to provide sufficient estimation of the maximum concentrations and elevations were based on the AERMAP model run output. The receptor spacing is as follows:

 50-meter spacing along the fence line  50-meter spacing from the fence line to 1,000 meters beyond the fence line  200-meter spacing from 1,000 meters to 5,000 meters beyond the fence line In total, cancer and non-cancer risks were evaluated at 5,402 receptors. The receptor breakdown is as follows:

 Receptors 1 through 5,337: Gridded Receptors  Receptors 5,338 through 5,400: Census Receptors  Receptors 5,401 through 5,402: Sensitive Receptors

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Figure 2 of the Air Study shows the receptor grid showing the receptor grid spacing overlaid on an aerial map. Census receptors within the modeling domain were extracted directly from HARP2 and are based on 2010 census data. Sensitive receptors include schools (kindergarten through 12th grade), day care centers, nursing homes, retirement homes, health clinics, and hospitals.

Figure 9 (Figure 2 within the Air Study)– AERMOD Grid See larger version of the image in Air Study (Attachment I)

Health Risk Modeling Carcinogenic

The point of maximum impact (PMI), maximally exposed individual residence (MEIR) excess cancer risks were evaluated using the 30-year exposure duration scenario. The maximally exposed individual worker (MEIW) cancer risk was evaluated using the 25- year exposure duration as recommended in the OEHHA Guidelines2. Based on the Risk Management Guidance for Stationary Sources of Air Toxics3, the Derived (Adjusted) Method in HARP 2 was used for the excess cancer risk assessment, which uses the 95th percentile breathing rate from the 3rd trimester to 2 years and the 80th percentile inhalation rate from 2 years to 70 years for MEIR excess cancer risk assessments. The 30-year and 25-year exposure durations for the MEIR and MEIW were obtained from the OEHHA Guidelines.

2 Office of Environmental Health Hazard Assessment (OEHHA), 2015. Air Toxics Hot Spots Program Risk Assessment Guidelines, The Air Toxics Hot Spots Program Guidance Manual for Preparation of Health Risk Assessments. Director, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, George V. Alexeeff, Ph.D. February 2015. 3 California Air Resources Board (ARB), 2015. Risk Management Guidance for Stationary Sources of Air Toxics. California Air Pollution Control Officers Association. July 2015.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Excess cancer risks were evaluated based on the annual toxic emissions impacts at ground level, inhalation cancer potency, oral slope factor, frequency and duration of exposure at the receptor, and breathing rate of the exposed persons. The MEIW incremental cancer risk was conservatively assumed to occur at the maximum impacts receptor in the modeling domain to account for new industrial activities potential to occur anywhere within the modeling area.

Non-Carcinogenic

The PMI, MEIR, MEIW and maximum sensitive receptor non-carcinogenic acute and chronic health effects were evaluated using the default OEHHA input assumptions. The health index is obtained by dividing the calculated increase acute and chronic risk by the acute and chronic RELs. Chronic toxicity is defined as adverse health effects from prolonged chemical exposure, caused by chemicals accumulating in the body. Acute toxicity is defined as adverse health effects caused by a brief chemical exposure of no more than 24 hours. To assess chronic and acute non-cancer exposures, annual and 1- hour toxic air contaminant ground-level impacts are compared with the reference exposure levels (REL) developed by OEHHA to assess the chronic or acute hazard index.

HARP Options The most recent version of HARP 2 (Version 17052), with the revised unit risk and cancer potency values, version 17228, was used for this analysis. The updated sensitivity factors were applied in accordance with the current regulatory guidance.

The deposition rate modeled in HARP 2 was set to 0.02 meters per second because the facility sources are considered controlled. In addition to inhalation exposure, the HRA assesses potential health impacts related to exposure from farm produce, mother’s milk, dermal absorption (mixed climate), and soil ingestion as required by OEHHA guidelines.

Exposure Pathways

For this analysis, the following applicable exposure pathways in Table 10 were included for each risk scenario:

Table L (Table 11. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis) Exposure Pathways

Table 10. Exposure Pathways

Risk Analysis Modeled Exposure Intake Rate Percentile Pathways Acute/8-Hour Inhalation OEHHA Derived Method Inhalation Non-Cancer Chronic OEHHA Derived Method Soil Ingestion

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Risk Analysis Modeled Exposure Intake Rate Percentile Pathways Dermal Absorption Mother's Milk Farm Produce Inhalation Soil Ingestion RMP using the Derived Cancer Dermal Absorption Methodology Mother's Milk Farm Produce

The OEHHA Derived Method for non-cancer chronic assessments uses the 95th percentile (High End) values for calculation for the inhalation pathway and the next two risk driving pathways while the remaining exposure pathways will use the 65th percentile values (Mean). The RMP using the Derived Methodology uses the 95th percentile values for all inhalation risk calculations.

Health Risk Assessment Results

Table 11 of the Air Study presents the results of the HRA based on the modeling and risk assessment methodology presented above. As noted above, the MEIW results are based on the impact results at the PMI, assuming workers are exposed only during work hours. This is the reason for the difference between the PMI and MEIW excess cancer risks. Figure 3 shows the location of the excess cancer risk and acute and chronic hazard index for the PMI, MEIR, and MEIW.

Figure 10 – (Figure 3 within the Air Study) HARP Impacts

See larger version of the image in Air Impacts Study

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Table M (Table 12. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

(Table 12). Mariposa Biomass Health Risk Assessment Results

Risk Impacts Value Rec UTM*-X UTM*-Y Number Cancer Risk at PMI (per million) 21.7 274 233850 4155050 Cancer Risk at MEIR (per million) 2.4 1754 234550 4155150 Cancer Risk at Sensitive (per million) 0.4 5402 237913 4153246 Cancer Risk at MEIW (per million) 1.8 274 233850 4155050 Chronic Risk at PMI 0.079 274 233850 4155050 Chronic Risk at MEIR 0.009 1754 234550 4155150 Chronic Risk at Sensitive 0.001 5402 237913 4153246 Chronic Risk at MEIW 0.079 274 233850 4155050 Acute Risk at PMI 0.278 1754 234550 4155150 Acute Risk at MEIR 0.278 1754 234550 4155150 Acute Risk at Sensitive 0.019 5402 237913 4153246 Acute Risk at MEIW 0.278 1754 234550 4155150

The exhaust stack height was developed to balance aviation safety concerns with air quality/public health impacts. Reducing the exhaust stack height from the proposed 60 feet would result in higher air dispersion modeled ground-level impacts due to a lower release height. In addition, lowering the exhaust stack height could result in building-induced downwash of the exhaust plume, which is caused by building or structures wake effect resulting in a downward trajectory winds in the project area. This downward wind trajectory causes the exhaust plume to also be directed downward, resulting in less plume dispersion and higher modeled ground-level concentrations.

Long Term and Cumulative Impacts

With the project emissions below thresholds of significant impacts, potential long-term impacts are also insignificant.

Regarding potential cumulative air quality impacts, one of the principal air quality impacts in the region is the pile and burning of woody biomass waste from forest management operations. Per the calculations in Table 6, the proposed bioenergy project actually reduces cumulative impacts.

In summary, the project has a less than significant impact related to air contaminants.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

e. Create objectionable odors affecting a substantial number of people? There are no sensitive receptors near the site and the project is not expected to produce any objectionable odors.

The proposed project is not considered a major source of odor emissions. The project could introduce new odor sources in the project area such as from anaerobic activity in the storage piles of biomass feedstock, and additional diesel vehicle emissions. However, such odor sources at the site are not expected to impact adjacent land uses, as project operations include measures to avoid anaerobic activity in the storage piles by minimizing chip storage times. While the impact is expected to be less than significant, the project has agreed to take all reasonable measures to reduce odors, in the event any off site odors are detected.

Mitigation Measure Air Quality 3 (e) 1: An operational management plan that includes 1) odor control activities and 2) methods for the project operations that demonstrate industry standard protocols for any nuisance odor and 3) best management practices shall be prepared by an appropriately licensed air professional and approved by the MCAPCO prior to building permit issuance.

Monitoring for Mitigation Measure Air Quality 3 (e).1: Approval of the plan as required by the MCAPCO and Planning Department verification prior to building permit issuance is required. Based on the incorporation of this mitigation measure into the approval for this project, the project will have a less-than-significant impact due to objectionable odors.

IV. BIOLOGICAL RESOURCES – Would the project: Less Than Potential Significant ly Less Than with No Significa Significant Mitigation Impact nt Impact Incorporatio Impact n a) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, ☐ ☒ ☐ ☐ or by the California Department of Fish and Game or U.S. Fish and Wildlife Service? b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional ☐ ☐ ☒ ☐ plans, policies, regulations or by the California Department of Fish and Game

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

or U.S. Fish and Wildlife Service? c) Have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the CWA (including but ☐ ☒ ☐ ☐ not limited to marsh, vernal pool, coastal, etc) through direct removal, filling, hydrological interruption or other means? d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with ☐ ☒ ☐ ☐ established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites? e) Conflict with any local policies or ordinances protecting biological resources, ☐ ☒ ☐ ☐ such as a tree preservation policy or ordinance? f) Conflict with the provisions of an adopted Habitat Conservation Plan, ☐ ☐ ☐ ☒ Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?

Discussion

The County has already determined that there are no significant impacts to biological resources when it approved PDZ 87-1 and the LDA MND, nevertheless the project conducted both a biological and botanical survey, and agree to several voluntary mitigation measures. See Attachments J and K for full versions of both studies. a) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Game or U.S. Fish and Wildlife Service?

The California Natural Diversity Database does not show any special-status habitats within 5 miles of the Study Area. Nevertheless, a field survey was conducted at the time of year appropriate to determine if special-status species were present, and were further assessed for their likelihood to occur within the Study Area based upon previously documented occurrences, field surveys, their habitat requirements, and the quality and extent of any suitable habitat within the Study Area. Each species was ranked for its likelihood to occur within the

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Study Area: a "high" rank was given for species where current field surveys have positively identified the species within the Study Area, where there have been previously documented occurrences within the Study Area, and/or where essential habitat elements exist within the Study Area; a "moderate" rank was given for species that were not detected during current field surveys, but where there have been previously documented occurrences within the Study Area or vicinity, and where preferred habitat elements exist within the Study Area; a "low" rank was given for species with no known observations within the Study Area or vicinity, and where habitat elements exist within the Study Area or vicinity, but the quality of that habitat is degraded or of poor quality, and/or where Study Area conditions and land uses deter its use of the Study Area; and a “unlikely” rank was given for species with no known observations within the Study Area or vicinity, and where no suitable habitat exists within the Study Area. The following special-status species were determined to have a moderate or high likelihood of occurrence within the Study Area where serpentine soils are present: Beaked clarkia, Mariposa clarkia, Mariposa cryptantha, Congdon’s lomatium, shaggy hair lupine and Mariposa daisy. Based on these results within the biological study, a more detailed botanical survey found as Attachment K was conducted. No special plant species were detected.

No special-status species were detected within the Study Area. Information was gathered from the US Fish and Wildlife Service as is attached within the Biological Study. Some portions of the Study Area containing gray pine woodland habitat have a low to moderate potential for occurrence of the following plants known to occur in woodland habitats: Mariposa daisy, Madera leptosiphon, Mariposa lupine, and slender-stalked monkeyflower, but none were detected within the botanical study. The portions of the Study Area containing serpentine soils have a moderate to high potential for occurrence of the following plants known to occur on serpentine soils: Mariposa clarkia, Beaked clarkia, Mariposa cryptantha, Congdon’s lomatium and shaggy hair lupine. The biological field survey and the botanical field survey failed to detect these rare species. As designed, the current project footprint will impact primarily ruderal/developed habitat and gray pine woodland. If project implementation involves ground disturbance or habitat conversion in areas containing gray pine woodland or serpentine soils, there is some chance that rare plant species not detected in the field survey could be impacted. Also, special-status animal species that occur in the vicinity could migrate onto the Study Area between the time that the field survey was completed and the start of construction. Because special-status animal species that occur in the vicinity could migrate onto the Study Area between the time that the field survey was completed and the start of construction, additional pre-construction surveys is recommended to mitigate any potential impact to a less than significant level. Thus with mitigation applied, impacts are less than significant.

Mitigation Measure 4.a.1.: A pre-construction survey based on CDFW protocols and survey periods for special-status species shall be performed by a qualified biologist to ensure that special-status species are not present. If any listed species are detected, construction shall be delayed, and the appropriate wildlife agency (CDFW and/or USFWS) shall be consulted and 66

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project impacts and mitigation reassessed and applied in conformance with biologist, CDFW and/or USFWS protocols. A verification letter from the CDFW that the survey was completed and protocols met shall be submitted to the Mariposa County Planning Department and approved by the Planning Director prior to grading or building permit issuance.

Monitoring for Mitigation Measure 4.a. 1: This mitigation measure will be monitored by the Mariposa County Planning Department prior to grading or building permit issuance. b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Game or U.S. Fish and Wildlife Service?

As Stated in the LDA MND, the significant impact would be one that adversely affects riparian habitat or another sensitive natural community. There are two minor seasonal drainages on or near the project site; neither of these drainages is designated as a blue-line stream. At the time of staff's site visit there was no water present in either drainage. Based on staff observation of the project site and the project design, the project will have a less-than-significant impact on natural communities. c) Have a substantial adverse effect on federally protected wetlands as defined by Section 404 of the CWA (including but not limited to marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption or other means?

The LDA MND states that there are no federally designated wetlands at the site. An informal assessment of the Study Area within the Biological Study identified a potentially-jurisdictional water feature in the Study Area: an ephemeral channel. Drainage ditches are also present.

Mitigation Measure 4.c.1: A 10 foot setback shall be in place from the centerline of the onsite ephemeral drainage channel identified within the project Biological Study for protection during construction and operation: there will be no modification of stream banks or adjoining vegetation within the 10 foot setback either during construction or during operation. A surveyed site plan prepared by a licensed land surveyor shall show the setback on all construction plans for grading and/or building permit application. Setback shall be flagged in the field prior to construction activities; flagging shall be maintained for the duration of the construction project.

Monitoring for Mitigation Measure 4.c.1: This mitigation measure will be monitored by the Mariposa County Planning Department and as a part of the grading and building permit review and inspection process.

d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

The Study Area contains suitable nesting habitat for various bird species because of the presence of trees and dense brush. No nests or nesting activity was observed in the Study Area during the field survey. If construction activities are conducted during the nesting season, nesting birds could be directly impacted by tree removal and indirectly impacted by noise, vibration, and other construction-related disturbance.

Mitigation Measure 4.d.1. : If construction activities will occur during the nesting season (usually March to September), pre-construction surveys for the presence of special-status bird species or any nesting bird species should be conducted by a qualified biologist within 500 feet of proposed construction areas. If active nests are identified in these areas, CDFW should be consulted to develop measures to avoid “take” of active nests prior to the initiation of any construction activities. Avoidance measures may include establishment of a buffer zone using construction fencing or the postponement of vegetation removal until after the nesting season, or until after a qualified biologist has determined the young have fledged and are independent of the nest site. e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?

According to the LDA MND the Project must consider any Oak Woodlands Conservation Plan in place, and shall preserve oak trees by abiding with the following mitigation measure below. No Oak trees are expected to be removed through the development of this project, however, the following mitigation measure will reduce this potential impact to a less than significant level: Mitigation Measure 4.e.1.: There shall be no grading, leveling, soil compaction from the use of heavy equipment, or digging within the root zone of oaks identified in a pre-construction oak tree survey. During construction of onsite improvements, all such oaks located in the area of construction activity identified as not to be removed, shall have erected around the root zone- which is 1 ½ times the drip line of the oak tree crown or 15' whichever is greater-• environmentally sensitive area fencing. This fencing shall remain installed, visible, and in good condition until all road construction, grading activities and other soil disturbance activities are completed. At the time of inspection of the completed improvements by the Building Department, Planning Director authorization for removal of the environmentally sensitive area fencing may be granted.

Monitoring for Mitigation Measure 4.e.1: This mitigation measure will be monitored by the and the Mariposa County Planning Department f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?

As stated in the LDA MND, the Project site is not part of any adopted Habitat Conservation Plan (HCP), Natural Community Conservation Plan (NCCP), or other local habitat conservation plan. Thus, the project will not impact an adopted conservation plan.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

V. CULTURAL RESOURCES – Would the project: Less Than Significant Potentially Less Than with No Significant Significan Mitigation Impact Impact t Impact Incorporati on a) Cause a substantial adverse change in the significance of a historical resource ☐ ☐ ☐ ☒ as defined in ‘15064.5? b) Cause a substantial adverse change in the significance of an archaeological ☐ ☐ ☐ ☒ resource pursuant to ‘15064.5? c) Directly or indirectly destroy a unique paleontological resource or site or unique ☐ ☐ ☐ ☒ geologic feature? d) Disturb any human remains, including those interred outside of formal ☐ ☐ ☒ ☐ cemeteries?

Discussion

No cultural resources were previously recorded or newly identified within the 5.27-acre area surveyed for the Project in the recently developed Cultural Resources Study available upon request and referenced herein by placeholder Attachment L. Thus, the Project does not have the potential to cause a significant impact on any resource that currently qualifies as a historical resource, or that has been recommended eligible for listing in the CRHR.

a) Cause a substantial adverse change in the significance of a historical resource as defined in ‘15064.5? According to the LDA MND and the recent Cultural Resources study, there are no such resources at the site. b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to ‘15064.5?

c) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

d) Disturb any human remains, including those interred outside of formal cemeteries?

Answer b,c,d: A current study available in the project file a the County Planning Department, was completed under the provisions of CEQA. Section 21083.2 of the statute and Section 15064.5 of the CEQA Guidelines provide instructions for a lead agency to consider the effects of Projects on historical resources and cultural resources.

Based on the results of the pre-field research, field survey, and assessment of potential direct or indirect Project impacts, no additional cultural resources work is recommended at this time. Considering a portion of the Project area has been disturbed by construction of a graded gravel road, by grading an approximately 1-acre area, and by an unimproved two-track, and that the entire area is underlain by thin, weakly developed soils with no potential for buried soils representing former landscapes above the existing bedrock, the potential for the discovery of buried archaeological materials within the Project area is considered to be low.

Should cultural resources be encountered during ground disturbing activities for the Project, however, work must be halted in that area within 50 feet of the find and a qualified archaeologist notified immediately to assess the significance of the find. Construction activities could continue in other areas. If the discovery proves to be significant, additional work, such as data recovery excavation, may be warranted and would be discussed in consultation with the property owner, the Mariposa County Resource Conservation District, or any other relevant regulatory agency, as appropriate.

Although unlikely, the discovery of human remains is always a possibility. State of California Health and Safety Code Section 7050.5 covers these findings, except on federal lands. This code section states that no further disturbance shall occur until the County Coroner has made a determination of origin and disposition pursuant to PRC Section 5097.98. The County Coroner must be notified of the find immediately. If the human remains are determined to be of Native American origin, the Coroner will notify the NAHC, which will determine and notify a Most Likely Descendent (MLD). The MLD shall complete the inspection of the site within 48 hours of notification and may recommend scientific removal and nondestructive analysis of human remains and items associated with Native American burials.

Compliance with state law is enough to ensure protection of any unexpected remains that however unlikely may be found at the site, so no impact is expected and no mitigation is required, however, through consultation with tribal groups pursuant to PRC 21080.3.1 & 2 a recommendation for monitoring during excavation activities was made. (Also See Section XVII. TRIBAL CULTURAL RESOURCES section of this Initial Study.) The project will voluntarily include the following mitigation:

Mitigation Cultural Resources 5.d.1 A Native American monitor shall be on-site for the duration of ground disturbance. During road grading, soil testing and/or construction, or any activity that involves ground disturbance necessary to implement project conditions of approval, if any signs of prehistoric, historic, archaeological, paleontological resources are evident, all work activity 70

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within fifty feet of the find shall stop and the Mariposa County Planning Department shall be notified immediately. No work shall be done within fifty feet of the find until Planning has identified appropriate measures to protect the find and those measures have been implemented by the applicant. Protection measures for the site may include, but not be limited to, requiring the applicant to hire a qualified archaeologist who shall conduct necessary inspections and research, and who may supervise all further ground disturbance activities and make any such recommendations as necessary to ensure compliance with applicable regulations. In addition to the Planning Department, the Mariposa County Coroner and the Native American Heritage Commission shall be notified should human remains be discovered. If the remains are determined by the Native American Heritage Commission to be Native American, the NAHC guidelines shall be adhered to in treatment and disposition of the remains. Representatives of the Most Likely Descendant shall be requested to be on-site during disturbance and/or removal of human remains.

Monitoring for Mitigation Measure 5.d.1: The applicant or his on-site designee shall be responsible for ensuring compliance with this mitigation. Proof of monitoring agreement shall be provided to the Planning Department prior to building or grading permit issuance. Based on the incorporation of this mitigation measure into the approval for this project, the project will have a less-than-significant impact on cultural resources.

VI. GEOLOGY AND SOILS – Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: i) Rupture of a known earthquake fault, as delineated on the most recent Alquist- Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area ☐ ☐ ☐ ☒ or based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42. ii) Strong seismic ground shaking? ☐ ☐ ☒ ☐ iii) Seismic-related ground failure, ☐ ☐ ☒ ☐ including liquefaction?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

☐ ☐ ☒ ☐ iv) Landslides? b) Result in substantial soil erosion or the ☐ ☐ ☒ ☐ loss of topsoil? c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and ☐ ☐ ☒ ☐ potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse? d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform ☐ ☐ ☒ ☐ Building Code (1994), creating substantial risks to life or property? e) Have soils incapable of adequately supporting the use of septic tanks or ☐ ☐ ☒ ☐ alternative waste water disposal systems where sewers are not available for the disposal of waste water?

Discussion No new information is needed pertaining to geology or soils as the geology and soils conditions remain since the approval of PDZ 87-1.

a) Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

i) Rupture of a known earthquake fault, as delineated on the most recent Alquist- Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42.

ii) Strong seismic ground shaking?

iii) Seismic-related ground failure, including liquefaction?

iv) Landslides? Answer a. The County determined when it approved PDZ 87-1 and the LDA that created the subject parcel that there was less than significant earthquake risk at the site; no new information is needed. Here is the information provided from the LDA MND:

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

“A significant impact would be one that exposes people or structures to loss, injury or death. Earthquake Faults: The Seismic Hazards Act of 1990 directs the California Department of Conservation to map the state's most prominent earthquake hazard area in California. These areas are called "Special Study Zone" and appear on a set of maps named the Alquist-Priolo Earthquake Fault Zone maps. Mariposa County is not a Special Study Zone and a map has not been created for Mariposa. The majority of the County falls within the lowest earthquake hazard zone of 10-20% probability. However, the potential for earthquakes and related hazards does exist in Mariposa County. A Five County Seismic Safety Study completed in 1974 by the Counties of Fresno, Kings, Madera, Mariposa, and Tulare found that fault zones do exist within and around Mariposa County and contribute to earthquake activity experienced within the County. The two fault zones within Mariposa making up the Foothill Fault System include the Bear Mountain Zone and the Melones Zone (Earthquake Fault Map, Figure 15-4, Technical Background Report - Mariposa County proposed General Plan, 2002), both of which are located on the western side of the County. The Foothill Fault System is considered active. Additionally, three other faults known to be active near Mariposa include the San Andreas Fault to the West, the Owens Valley Fault to the East and the White Wolf fault to the South. According to the Five County Study, the three faults may cause small periodic local earthquakes.

The project site is located just outside the Mariposa Town Planning Area, in the midst of the Melones Fault Zone. However, Mariposa falls within the lowest earthquake hazard zone of 10-20% probability - the lowest risk category for seismic activity. No earthquake with a magnitude above 5 has occurred in Mariposa County since 1800. If earthquakes do occur, records show they occur at around magnitude 2.7 or less. Table 15-2 in the Technical Background Report referenced above indicates that earthquakes at this magnitude are felt by very few people and no damage will occur. According to the Mariposa County Seismic Hazard Map (Exhibit 8-B, General Plan), the project site lies within Seismic Zone 2, which is considered to have a low risk of earthquakes. Thus, the project will have less than significant impact.

Ground Shaking: The County requires that the standards of the Uniform Building Code Seismic Zone 3 be met, which should be sufficient to limit the effects of ground shaking on the project site, should such activity ever occur. Thus, the project will have less than significant impact. Ground Failure: Soil on site is Henneke extremely rocky clay loam. According to the US Department of Agriculture Soil Survey for Mariposa County, this soil is excessively drained, permeability is slow, and is underlain at a depth of 10" to 20" by serpentine bedrock. These factors make the probability of liquefaction hazard very low. Thus, the project will have a less than significant impact. Landslides: The State's Seismic Hazard Mapping Program has not yet mapped the County to determine the probability of landslide occurrence as a result of earthquake activity. According to a Seismic/Geologic Hazard and Microzone Map showing Mariposa County, the project site is not located in an area with any landslide risk. The Five County Seismic Safety Study 73

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performed a generalized landslide risk appraisal and found that there was minimal risk of landslides caused by earthquakes in areas of low relief and moderate to high risk found in the remaining mountainous areas of the County. Most of the soils found in the County have minimal amounts of clay and low shrink-swell potential and do not result in landslide hazards. According to the Technical Background Report for the proposed Mariposa County General Plan, there are two areas within the County that have a high risk of sliding; the project site is located in one of the two designated areas, along Highway 49, and has the soil profile associated with a high risk of sliding. However, since earthquake activity greater than magnitude five (5) has not occurred within Mariposa County, the occurrence of landslides as a result of earthquakes is unlikely. Many other factors can play a role in the development of landslides. Factors that may pertain directly to the subject project site include: rock types susceptible to sliding, steep slopes, heavy rainfall during winter months, and slopes that have been modified by development activity. Landslides generally occur on slopes of 15 percent or greater. The Project site's topography is generally of slopes between 10 and 30 percent. However, grading activity on the site will be done in a manner that takes these potential landslide risks into consideration, and the proposed building sites are located off of and away from the steeper slopes of the project area. A grading plan in accordance with Mariposa County's grading permit requirements will be required. Thus, the project will have less than significant impact.

b) Result in substantial soil erosion or the loss of topsoil?

Similar to Section a), the County also reviewed soil erosion when approving the LDA MND. Here is an excerpt from that document:

“A significant impact would be one that results in substantial soil erosion or loss of topsoil. Soil on site is Henneke extremely rocky clay loam. According to US Department of Agriculture Soil Survey for Mariposa County, this soil has a high hazard of erosion. Project development will require some grading for roads, driveways and homes. Site grading could substantially increase erosion. However, the standards of the County Grading Ordinance and standard requirement for re-vegetation will ensure a less than significant impact on the site.”

2018 County grading permit requirements require compliance with California Building Code, Appendix J-Grading that include erosion control measures to minimize soil erosion. Also, and Stormwater Pollution and Prevention Plan is required where best management practices further insure soil loss avoidance and erosion or loss of topsoil. c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse? d) Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial risks to life or property? Answer c, d: A significant impact would be one where soil becomes unstable as a result of

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

the project. Soil on site is Henneke extremely rocky clay loam. According to the US Department of Agriculture Soil Survey for Mariposa County, this soil is rated low for shrink- swell potential. The standards of the County Grading requirements, the Uniform Building Code, and the Road Improvement and Circulation Policy will ensure a less than significant impact on the site. Significant impact would also occur if the project is placed on expansive soils and creates substantial risk to life or property. As stated above the soil on site has a low shrink-swell potential. Thus, under the LDA MND, and the same soil conditions for the proposed project Thus, the project will have less than significant impact. e) Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water? The LDA MND states: “A significant impact would occur if septic tanks or systems are utilized in the project and the soil is unable to support their use. The Mariposa County Health Department has conducted a preliminary review of the project site and has concluded that based on the percolation testing conducted for this project, and the industrial use of the project site, they are able to support the use of a shared septic system for the property. The percolation and soils analysis testing conducted for this project noted that either Parcel 3 or Parcel 4 would be able to support a shared septic system for the property. Based on the existing regulations already in place, the project will have less than significant impact.” Since the adoption of the LDA MND a septic system with a 20 person capacity has been built on Parcel 4 and provides capacity for the Project, further demonstrating that the soil is adequate. Nothing has changed the soil quality on the parcels, therefore this conclusion remains valid.

VII. GREENHOUSE GAS EMISSIONS -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Generate greenhouse gas emissions, either directly or indirectly, that may ☐ ☐ ☒ ☐ have a significant impact on the environment? b) Conflict with an applicable plan, policy or regulation adopted for the ☐ ☐ ☐ ☒ purpose of reducing the emissions of greenhouse gases?

Discussion

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

CalEEMod was also used to assess the project construction greenhouse gas (GHG) emissions. Table 12 presents the results of the construction GHG assessment. The CalEEMod results are found in Appendix B of the Air Report found as Attachment I. Table N (Table 12. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 12. Construction GHG

Maximum Controlled Annual Pollutant Emissions (metric tons) Carbon Dioxide-Equivalent 360.54

CalEEMod was also used to assess the project operational mobile and temporary source greenhouse gas (GHG) emissions. Table 13 presents the results of the operational mobile GHG assessment. Table O (Table 13. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

Table 13. Mobile GHG Emissions

Maximum Controlled Annual Pollutant Emissions (metric tons) Carbon Dioxide-Equivalent 1,054.57

Using the above CalEEMOD data and calculated GHG emissions from the combustion of 12,000 BDT annually by the proposed facility and from the 60% reduction of open burning of the woody biomass waste, the following Table 14 of the Air Study results in the total GHG burden of the bioenergy facility. The 60% reduction in open burning is based on the Air Study and the biomass feedstock study found as Attachment R.

Table P (Table 14. from the Mariposa Biomass Project Air Quality and Greenhouse Gas Emissions CEQA Analysis)

(Table 14). Facility GHG Burden

Projected GHG Emission Source Emissions (CO2e in metric tons per year) 360.54 Construction Emissions 9 12 MT/year 10 Project Emissions 20,760 MT/year 76

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Mobile Operations 1054.57 MT/year 11 Reduced Open Pile Burning (-12,456) MT/year TOTAL 9,370.57MT/year Regarding the total GHG emissions whether it be the total gross GHG emissions (21,826.57 MT/year) or the net GHG emissions after considering the offset of GHG from reduced open pile burning (9,370.57 MT/year), it should be noted that the MCAPCD does not have a GHG emissions significant impact threshold value. The California Air Resources Board (CARB) has used 25,000 metric tons/year as a reporting threshold for the cap and trade program, but was not specifically established as a CEQA threshold for GHGs. However, in the report titled: CEQA and Climate Change: Evaluating and Addressing Greenhouse Gas Emissions from Projects Subject to the California Environmental Quality Act, the California Air Pollution Control Officers Association (CAPCOA) identifies the 25,000 metric ton threshold, as used by CARB for their reporting threshold, as a potential and appropriate non-zero GHG threshold for use in a CEQA document (see pages 44-45 of the above-referenced 2008 report13).

In summary, a 25,000 metric ton threshold has been determined in several state, federal, and international rulemaking processes to represent a significant level of emissions with respect to cumulative contributions to global climate change. Given the research and resources that went into the development of the GHG Mandatory Reporting Rule and cap and trade programs adopted by CARB, the U.S. EPA GHG reporting rule, and the fact that the 25,000 metric ton threshold would capture approximately 94 percent of GHG emissions associated with stationary sources in California (CAPCOA, page 44), this is the best test be used as the significant impact threshold for GHGs in the MCAPCD

It must be noted that Table 14 of the Air Study calculates the GHG emissions without considering the carbon neutrality of woody biomass. Woody biomass combustion for the production of electricity is considered to be carbon neutral by state, federal and international agencies. This is especially true when the woody biomass being burned is dead and down or needs to be removed for reasons of public safety and therefore the carbon in the wood would reenter the atmosphere within a matter of a few years anyway. CO2e emissions related to the

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

burning of woody biomass has been exempted from the California Cap and Trade program for this reason and, as such, it is reasonable to consider the calculation of total emissions as potentially carbon neutral when determining the project’s environmental impacts. If the project emissions in Table 9, i.e., the GHG emissions from the combustion of woody biomass, is considered zero, then the GHG burden of the proposed project is 1,067 MT/year.

a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?

Burning woody biomass can be considered “carbon neutral” in that CO2 emitted during this process is not from a fossil source. Additionally, this energy will displace energy on California grid that comes from fossil fuel, displacing that energy. The California RPS program, as discussed earlier within the GHG regulatory setting section, gives credit for such displacement to the Utility provider that will buy the energy from the Project (PG&E). This is clear evidence that there is a value that the project provides, and that the State recognizes the value of this renewable energy in terms of GHG reduction.

Also, as described above, when taking into consideration the fact that the biomass that will be utilized would have otherwise been open-pile burned or left to decompose, the removal of this waste and its associated emissions has a net-positive effect on the environment. Based on the avoided emissions from the alternative fates of the wood waste and the emissions are below the threshold of 25,000 metric tons of CO2e per year. The effect of this project on GHG emissions is less than significant.

b) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases?

Mariposa County has not yet developed a level of significance for CO2 emissions. However, using the significance threshold of 25,000 metric tons of CO2e per year, the project will not have a significant impact. California AB 32 Scoping Plan was developed to produce an 80 percent reduction of 1990 GHG emissions levels by 2050. As part of this program, emissions entities are incentivized to use cleaner alternatives – such as biomass. This project is consistent with these initiatives, and therefore there is no impact.

VIII. HAZARDS AND HAZARDOUS MATERIALS -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Create a significant hazard to the ☐ ☐ ☒ ☐

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

public or the environment through the routine transport/use/disposal of hazardous materials? b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and ☐ ☐ ☐ ☒ accident conditions involving the release of hazardous materials into the environment? c) Emit hazardous emissions or handle hazardous or acutely hazardous ☐ ☐ ☐ ☒ materials, substances, or waste within one-quarter mile of an existing or proposed school? d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code ☐ ☐ ☐ ☒ Section 65962.5 and create a significant hazard to the public or the environment? e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, ☐ ☐ ☒ ☐ would the project result in a safety hazard for people residing or working in the project area? f) For a project in the vicinity of a private airstrip, would the project result in a ☐ ☐ ☐ ☒ safety hazard for people residing or working there? g) Impair implementation of or physically interfere with an adopted ☐ ☐ ☐ ☒ emergency response plan or emergency evacuation plan? h) Expose people or structures to a significant risk of loss, injury or death ☐ ☐ ☐ ☒ involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

wildlands?

Discussion

The Project is located in an industrial park that was intended to include projects like the subject project. As such the standard requirement to prepare a plan to manage flammable liquids and other materials that could be hazardous will be required, and issues related to airport proximity are covered below. a) Create a significant hazard to the public or the environment through the routine transport/use/disposal of hazardous materials? b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?

Answer a and b: During construction and operational phases of the proposed project, common hazardous materials include gasoline and other motor vehicle fuels, propane, solvents, lubricating oils, welding gases, and acids and bases may be present onsite.

The proposed facility, once operating, must complete and submit Unified Program Consolidated (CUPA) Forms and must complete and submit Hazardous Materials Release Response Plan (Business Plan) to the County Environmental Health Department if handling or storing a hazardous material equal to or greater than the minimum reportable quantities. The estimated minimum hazardous materials quantities are:

● 55 gallons of liquid ● 500 pounds of a solid ● 200 cubic feet of compressed gas

It is estimated that the following hazardous materials will be stored on site: Propane: 20 tons or 10,420 gal, Nitrogen: 20 tons or 6000 gal Diesel: 1000 gal, Engine Lube Oil: 700 gal (storage) Engine Lube Oil: 342 gal (engine crankcase), Misc. Lube Oil: 250 gal Coolant (glycol): 250 gal (storage), Coolant (glycol): 250 gal (cooling circuit) Urea: 250 gal (for SCR) There will be no underground storage of hazardous liquids on site. The proposed facility, once operating, must complete and submit Unified Program Consolidated Forms and must complete and submit Hazardous Materials Release Response Plan (Business Plan) to the County Environmental Health Department, and comply with

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

said plan. The requirements (as a condition of approval) and adherence to this Plan will reduce the impact to less than significant. c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school?

There are no existing or proposed schools within one-quarter mile of the project site. Thus, the project will have no impact. d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and create a significant hazard to the public or the environment?

The project site is not listed on any of the lists of “hazardous materials sites” provided by the California Department of Toxic Substances Control. There will be no impact. e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard for people residing or working in the project area?

Below is an image reflecting the location of the Project in proximity to the airport Figure 11

The location for the proposed Mariposa Biomass Facility is 1.2 miles from the Mariposa-Yosemite Airport and therefore falls into the Mariposa-Yosemite Airport 81

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Influence Area. The project is also located near the County Solids Waste Facility.

In order to project public safety, the County has established a number of land use standards that include the height of structures located in the Airport influence area. In order clearly describe the height requirements in these standards, a series of imaginary surfaces define the protected airspace that airplanes use when taking off or landing. These surfaces are shown in the figure on the next page. Airplanes taking off or landing are expected to stay above these surfaces and ideally structures, trees and terrain will be below the surfaces. Given the nature of the terrain near the airport, e.g Mt. Bullion, there are obvious exceptions to this rule. From a land use planning point of view, structures below these surfaces meet requirements and that is the case with the structures associated with our proposed biomass facility. The tallest structure associated with the proposed project is the exhaust stack.

Figure 12

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

The Mariposa Biomass project’s surveyor, Nick Van Landingham, PLS, prepared the conical approach elevation exhibit (Attachment F). The exhibit demonstrates the proposed stack location be 1.2 miles from the nearest end of the airport runway and relation to the conical surface above the location.

The Airport Overlay District requires compliance with the Airport Master Plan and the Mariposa Yosemite Airport Comprehensive Land Use plan height requirements. The proposed air exhaust stack height of 60 feet cannot penetrate the “imaginary conical surface” pursuant to the Airport Plans. This conical surface defines the elevation of which a ground structure may not enter, thereby being the maximum height elevation of ground structures. The Airport Plans prescribe the methodology to measure and calculate the conical surface elevation at given points in relation to the distance from the Airport runway. Based on the methodology, the imaginary conical surface elevation directly above the proposed air exhaust stack location is 2532 feet. At the top of the proposed air exhaust stack of 60 feet, the elevation is 2454 feet. The top of the proposed air exhaust stack height is at an elevation of 2454 feet, being 78 feet below the imaginary conical surface elevation of 2454 feet and therefore in compliance with the Airport Plans and Airport Overlay District. To illustrate this, an exhibit of the surfaces as they relate to the height limitations for airport safety was prepared by a licensed land surveyor along with reference to Mead Hunt Airport Layout and Airspace plan sheets are included as Attachment F.

Figure 13 is a depiction of Attachment F

Additionally, the air dispersal plume from the exhaust stack was evaluated by TSS Consultants utilizing known thermal plume criteria and it was determined that the presence 83

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

of the thermal plume in the location “is not expected to result in an impact to aviation safety as aircraft will pass through the plume very quickly.” The analysis is included in Attachment F.

The project will notify the FAA of this new facility as it is in the Airport Influence areas. In conclusion, the Project will comply with the height limitations of the PDZ87-1, the County and the Airport plans, and therefore, there will be a less than significant impact. f) For a project in the vicinity of a private airstrip, would the project result in a safety hazard for people residing or working there?

There is no private airstrip within close proximity to the project, therefore there is no impact. g) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?

The Project would not impair the implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan, because of the remote location of the project which is located away from significant population centers, and because it would not block any public or private rights of way which could be necessary for emergency access. Additionally, the County has prepared a draft evacuation plan, and it determined when it approved the LDA MND that the development and construction of an industrial project such as this one would not adversely impact such plans. Thus, there will be no impact. h) Expose people or structures to a significant risk of loss, injury or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands?

The fuel loading in this area is moderate to heavy, consisting of grassland and transitioning into mixed oak woodland. The state adopted regulations for the purpose of establishing minimum wildfire protection standards in conjunction with building, construction and development in the State Responsibility Areas (SRA). These regulations, known as SRA Firesafe Regulations, provide for basic emergency access and perimeter wildfire protection measures. The project is subject to these regulations and will be designed in conformance with them. Also the project will assist in reduction of forest fuel loading and result in increased forest regrowth through the removal of waste. An overall decrease in wildfire risk for communities within 50 miles of the site will provide a net benefit. The project will have no impact, and is expected to help reduce the threat of wildland fire. With the application of State law conformance, there will be no impact.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

IX. HYDROLOGY AND WATER QUALITY -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Violate any water quality standards or ☐ ☐ ☐ ☒ waste discharge requirements? b) Substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or lowering of the local groundwater ☐ ☐ ☒ ☐ table level (e.g. production rate of pre- existing nearby wells would drop to a level which would not support existing or planned land uses for which permits have been granted)? c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the ☐ ☐ ☐ ☒ course of a stream or river, in a manner, which would result in substantial erosion or siltation on- or off-site? d) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or ☐ ☐ ☒ ☐ substantially increase the rate or amount of surface runoff in a manner, which would result in flooding on- or off-site? e) Create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage ☐ ☐ ☒ ☐ systems or provide substantial additional sources of polluted runoff? f) Otherwise substantially degrade water ☐ ☐ ☐ ☒ quality? g) Place housing within a 100-year flood hazard area as mapped on a federal Flood ☐ ☐ ☐ ☒ Hazard Boundary or Flood Insurance

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Rate Map or other flood hazard delineation map? h) Place within a 100-year flood hazard area structures, which would impede or ☐ ☐ ☐ ☒ redirect flood flows? i) Expose people or structures to a significant risk of loss, injury or death ☐ ☐ ☐ ☒ involving flooding, including flooding as a result of the failure of a levee or dam? j) Inundation by seiche, tsunami, or ☐ ☐ ☐ ☒ mudflow?

Discussion

The Project is equipped with a functioning well and well tests shows sufficient water volume and quality for use at the site, and the use of the well is not expected to instigate any drawdown issues. The Project has a drainage plan that will address storm water runoff and related issues.

a) Violate any water quality standards or waste discharge requirements? The gasification system will not generate any appreciable amount of waste water; approximately 60 pounds per day of a semi liquid material will be produced, which is covered in the solid waste section of this Study. b) Substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g. production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted)?

The completion report (No. 0930872) for the subject well dictates that it is 200 feet deep and taps four water-producing fractured quartz zones between 75 and 160 feet in depth. The well was constructed in March 2007 by Mariposa Well Drilling Co., Inc. On March 17, 2017, the static water level was 15 feet deep and the yield was 20 gpm after two hours of airlifting. Mariposa Well Drilling Co., Inc. conducted a six-hour constant discharge on the well on Sep•tember 27, 2017. The static water level was 29 feet deep, and was expected to be deeper than the earlier measurement, which was made in the spring, when water levels are normally shallower. The well was pumped at an average rate of 15 gpm. At the end of the pumping period, the pumping level was 76 feet. The drawdown was 47 feet and the specific capacity was 0.3 gpm per foot. Copies of the pump test measurements are attached.

A semilog plot of the drawdown measurements indicated a trans•missivity of 65 gpd per foot.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Water-level recovery was measured for 22 minutes after pumping stopped, when full recovery was at•tained. A semilog plot of uncorrected recovery also indicated a transmissivity of 65 gpd per foot. Copies of the plots are attached.

The Non-Equilibrium Formula was used to calculate the drawdown in the nearest residential well (700 feet distant) after 180 days of continuous pumping at 1.5 gpm in the absence of re• charge. Based on the hydrologist’s extensive experience with hard rock well test•ing in the Sierra Nevada, a storage coefficient of 0.01 was used. The equation used is found in the attached Hydrology Report, Attachment M. These calculations indicate that the drawdown in the closest off• site well would be insignificant. This drawdown would only occur if the offsite well tapped the same water producing fractured zones as the pumped well. Otherwise, the drawdown would be less. No impact is expected. c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, in a manner, which would result in substantial erosion or siltation on- or off-site?

The project will not alter the course of a stream or river, nor would it result in substantial erosion or siltation on or offsite. There will be no impact. d) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or substantially increase the rate or amount of surface runoff in a manner, which would result in flooding on- or off-site?

An informal assessment of the Study Area identified 1 potentially-jurisdictional water feature in the Study Area: an ephemeral channel. Drainage ditches are also present. In order to protect the stream during construction and operation, there will be no modification of stream banks or riparian vegetation, and while no setback is required the project will keep a 10 foot setback from the centerline of the drainage channel during both construction and operation. e) Create or contribute runoff water which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff? f) Otherwise substantially degrade water quality?

Answer e/f: This project will not have a significant effect on absorption rates, drainage patterns, or the rate and amount of runoff. The project will not have a significant effect due to the comparatively short duration of potential construction, the limited amount of grading, and the limited net loss of permeable area. The standards of the County Grading requirements and the Grading Plan found at Attachment E will ensure drainage is maintained and exposed soils are resewn. Additionally, the project will need to obtain a Storm Water Permit - a General Permit - under the California State Water Resources Control Board before building or grading permit is issued. Thus, the application of existing regulations applied to the Project ensures it will have a less than significant impact.

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

g) Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map? No housing is proposed as a part of this project; therefore, there will be no impact. h) Place within a 100-year flood hazard area structures, which would impede or redirect flood flows? Proposed structures on this site are neither proposed in a 100 year flood hazard area and are nor expected to impede or redirect flood flows and are not located within a floodplain. There will be no impact. i) Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam?

The project is not located near a river or in the floodplain, nor downstream from a dam of any consequence. No impact is expected. j) Inundation by seiche, tsunami, or mudflow?

The project site is not located near a large lake or the ocean. Therefore, there are no concerns regarding sieches or tsunamis and there are no formations near the site that are expected to cause a mudflow. There will be no impact.

X. LAND USE AND PLANNING -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Physically divide an established ☐ ☐ ☐ ☒ community? b) Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the project (including, but not limited to the general ☐ ☐ ☐ ☒ plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect? c) Conflict with any applicable habitat conservation plan or natural community ☐ ☐ ☐ ☒ conservation plan?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

Discussion

The site is zoned for industrial uses (PDZ87-1) and the proposed use is in conformance with permitted uses listed in PDZ87-1 such as a “processing use”, “agricultural product processing” and “other uses”.

a) Physically divide an established community?

There will be no impact as the project site has already been designated through the PDZ 87- 1and the LDA MND for this use. b) Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the project (including, but not limited to the general plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect?

The proposed project does not conflict with the County General Plan, Zoning, or the PDZ 87-1 or the Airport Land Use plan and will have no impact. c) Conflict with any applicable habitat conservation plan or natural community conservation plan?

None are in place at this site. No impact is expected.

XI. MINERAL RESOURCES -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Result in the loss of availability of a known mineral resource that would be of ☐ ☐ ☐ ☒ value to the region and the residents of the state? b) Result in the loss of availability of a locally important mineral resource recovery site delineated on a local ☐ ☐ ☐ ☒ general plan, specific plan or other land use plan?

Discussion There is no mining proposed by the project and no known mineral resources . 89

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

a) Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state?

b) Result in the loss of availability of a locally important mineral resource recovery site delineated on a local general plan, specific plan or other land use plan?

Answers a & b. A significant impact would occur if the project resulted in the loss of availability of a mineral resource of value to the region and state, or result in the loss of a locally important mineral resource shown on land use planning maps. The Mariposa County General Plan does not identify the project area as an important mineral recovery site. The project does not propose mineral extraction uses and involves limited grading and site disturbance where the project would not result in loss of availability of a known mineral resource that would be of value to the region and residents of the state. Thus, the project will have no impact.

XII. NOISE -- Would the project result in: Less Than Less Potentiall Significant Than y with No Significa Significan Mitigation Impact nt t Impact Incorporatio Impact n a) Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or ☐ ☐ ☐ ☒ noise ordinance, or applicable standards of other agencies? b) Exposure of persons to or generation of excessive groundborne vibration or ☐ ☐ ☐ ☒ groundborne noise levels? c) A substantial permanent increase in ambient noise levels in the project ☐ ☐ ☐ ☒ vicinity above levels existing without the project? d) A substantial temporary or periodic increase in ambient noise levels in the ☐ ☒ ☐ ☐ project vicinity above levels existing without the project?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would ☐ ☐ ☐ ☒ the project expose people residing or working in the project area to excessive noise levels? f) For a project within the vicinity of a private airstrip, would the project expose ☐ ☐ ☐ ☒ people residing or working in the project area to excessive noise levels?

Discussion

The noise regulations applicable to the industrial park are 75 dBA at internal property lines and 55 dBA at Highway 49. The main source of noise from the bioenergy plant is the engine generator. The engine generators will be located in sound attenuating enclosures to ensure that the noise level at Highway 49 will not exceed 55 dBA and will not exceed 75 dBA at the property lines. The other two major sources of noise is the front end loader and chip trucks that deliver biomass to the facility. The feed system is designed to hold 16 hours of inventory, before it needs to be refilled by the front end loader. This will insure that the front end loader operation will be limited to 12 hours/day. Truck deliveries will be limited to 7 AM to 5 PM, six days a week, Monday through Saturday. A Noise Study found as Attachment N was prepared by Ballard and Associates. The study concluded that the noise generated by the facility will not exceed the noise limits applicable to the industrial park. In addition, the study evaluated the noise impact on the residences in Mykleoaks Ranches. The night time noise levels measured at the nearest residences are very low (~40 dBA), and the study concluded there should be no noticeable increase in noise levels as a result of the operation of the bioenergy facility. Note that the airport location was not impacted. All of the answers below are based on the Project Noise Study submitted. In an abundance of caution, the project has agreed to noise testing to be conducted upon commencement of normal site operations to verify the reference sound level data provided by the project applicant and to incorporate any additional noise control measures which may be determined to be warranted as a result of that testing.

a) Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? b) Exposure of persons to or generation of excessive groundborne vibration or groundborne noise levels?

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

c) A substantial temporary or permanent increase in ambient noise levels in the project vicinity above levels existing without the project? d) A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project?

Answer to a,b,c.d The Mariposa County General Plan Noise Element does not contain numeric noise standards. Therefore, this analysis utilizes the FICON methodology for establishing significance criteria. Based on the average noise measurement results shown in Table 1, it is clear that existing ambient conditions are well below 60 dB Ldn at the nearest residences to the project site. Therefore, the noise standards used to assess project noise impacts are ambient plus 5 dB according to the Table 3 of the Study criteria.

Based on the FICON research shown in Table 3 of the Noise study, a 5 dB increase in noise levels due to a project is required for a finding of significant noise impact where ambient noise levels without the project are less than 60 dB Ldn. Because ambient noise levels at the nearest residences to the project site were quantified as being below 60 dB Ldn, a 5 dB increase in average ambient noise levels is considered the threshold of significance for this project at the nearest residential receptors.

The proposed project would generate noise in three distinct areas. The first is noise generated by heavy trucks accessing the site and dumping biomass material at the lower storage area. The second is the front-loader which will travel between the lower biomass storage area and plant area, and the third is the plant-area equipment. As noted previously, noise would be generated 24-hours per day by the plant area equipment. However, truck unloading and front- loader operations would be limited to daytime hours.

BAC utilized noise level data provided by the project applicant which was collected at a reportedly similar biomass facility to predict the noise generation of the plant area equipment. For on-site truck and front-loader movements, reference noise level data contained in the Caltrans Roadway Construction Noise Model (RCNM) and BAC file data were utilized. Table 92

Conditional Use Permit Application No. 2017-117 Mariposa Biomass Project Jay Johnson, Applicant. Initial Study, 2018

4 of the Noise Study contains the reference sound levels for the various components of the project. Table 5 of the Noise Study contains the distances between each noise-generating component of the project and the nearest sensitive receptors.

The reference sound pressure levels for each on-site, noise-generating, component of the project were projected to the twelve nearest residences to the project site using the sound propagation characteristics described above. Table 6 of the Noise Study contains the results of those propagation calculations.

The Table 6 of the Noise Study data indicate that the on-site noise generation of the project would be within compliance with all of the project’s noise standards of significance during both daytime and nighttime periods. As a result, no specific recommendations for noise mitigation measures are warranted at this time. However, because these conclusions are based on extensive modelling using data provided by others, BAC recommends that follow-up noise testing be completed once the plant is fully operational to verify the reference noise levels utilized in these calculations.

In addition to the noise levels predicted at the nearest residences, noise levels were also predicted at the closest site property lines. The results of those calculations indicate that the average noise levels generated by the project would not exceed 63 dB Leq at the nearest property line. This level is in compliance with the Mariposa Industrial Park standard of 70 dBA at the project site property line.

According to the project traffic study, the proposed project would generate approximately 46 daily vehicle trips on Highway 49, of which 26 would be light duty trucks (pickup trucks). If large wood chip trucks (heavy trucks) are used to transport material to the site, only 3-4 per day would be required. So the actual number of daily truck trips to the site will depend on the size of the trucks delivering the materials, but, on average, it would not be more than 3-4 heavy trucks in any given day.

According to published Caltrans traffic, there are approximately 6,100 daily vehicle trips on Highway 49 at the project site, of which approximately 146 are heavy trucks. As a result, the project is not anticipated to result in an appreciable change in traffic noise levels at existing residences located closest to Highway 49. Nonetheless, a quantitative analysis of Highway 49 traffic noise levels was conducted for this assessment.

The Federal Highway Administration Highway Traffic Noise Prediction Model (FHWA-RD- 77-108) with the Calveno vehicle noise emission curves was used with traffic data provided by the project transportation consultant and Caltrans to predict traffic noise levels on Highway 49 both with and without the Project. Table 7 of the Noise Study shows the results of the Project- generated traffic noise impact analysis at the nearest residences to the project site access route, at a distance of 230 feet from the roadway centerline. The FHWA Model inputs and results are provided in Appendices E & F, respectively, of the Noise Study.

Table 7 of the Noise Study data indicate that project-generated traffic noise level increases would not exceed the 5 dB threshold on Highway 49 under either peak hour or 24-hour average 93

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conditions. As a result, no adverse off-site traffic noise impacts are identified for this project.

The noise generation of the proposed project is predicted to be satisfactory relative to both the noise standards of the Mariposa Industrial Park PDZ 87-1 and CEQA guidelines during both daytime and nighttime conditions, for both onsite operations and off-site traffic. As a result, no adverse noise impacts are identified for this project, and no noise mitigation measures would be warranted at this time. However, BAC recommends that follow-up noise testing be conducted upon commencement of normal site operations to verify the reference sound level data provided by the project applicant and to incorporate any additional noise control measures which may be determined to be warranted as a result of that testing. The Project will follow up with noise testing to be conducted upon commencement of normal site operations to verify the reference sound level data provided by the project applicant and to incorporate any additional noise control measures which may be determined to be warranted as a result of that testing.

Mitigation Measure 12d.1: Within the facility start up and operational testing period and prior to building permit certificate of occupancy, a noise monitoring report shall be submitted to the Planning Director for review and verification that project operating noise levels do no exceed the allowances pursuant to PDZ-87-1. If the monitoring report finds that the noise thresholds are in exceedance of PDZ87-1 allowances, then the report shall provide recommendations for appropriate noise reduction measures that reduce noise levels to meet the PDZ87-1 standards and those recommendations shall be incorporated into the project. A certificate of occupancy shall not be issued until the noise monitoring concludes. The report shall be prepared by an appropriately licensed professional.

Monitoring for Mitigation Measure 12.d.1: The applicant or his on-site designee shall be responsible for ensuring compliance with this mitigation and Planning Department verification is required prior to Certificate of Occupancy. Based on the incorporation of this mitigation measure into the approval for this project, the project will have a less-than-significant noise impacts.

e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels?

The project is located within an airport land use plan, but noise is not expected from the airport that would affect Project success or be heard by the people working at the facility. County airport plans include only restrictions and limitations on residential construction; not industrial facilities like this one. PDZ 87-1 noise standard compliance is required. No impact will occur. f) For a project within the vicinity of a private airstrip, would the project expose people residing or working in the project area to excessive noise levels?

No private airstrips in area, therefore no impacts are expected.

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XIII. POPULATION AND HOUSING -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Induce substantial population growth in an area, either directly (for example, by proposing new homes and businesses) ☐ ☐ ☐ ☒ or indirectly (for example, through extension of roads or other infrastructure)? b) Displace substantial numbers of existing housing, necessitating the ☐ ☐ ☐ ☒ construction of replacement housing elsewhere? c) Displace substantial numbers of people, necessitating the construction of ☐ ☐ ☐ ☒ replacement housing elsewhere?

a) Induce substantial population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)? b) Displace substantial numbers of existing housing, necessitating the construction of replacement housing elsewhere? c) Displace substantial numbers of people, necessitating the construction of replacement housing elsewhere?

Answer a, b, c. The project is consistent with PDZ 87-1 and the LDA MND as approved by the County, and will not trigger any new needs for additional housing; infrastructure or replacement housing. The project does not displace any existing housing nor displace substantial numbers of people as there are no residences at the project nor is a substantial growth inducing employer as the Project is expected to bring 8-10 jobs into the area, which will not trigger the need for new services. There will be no impact.

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XIV. PUBLIC SERVICES

a) Would the project result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n

Fire protection? ☐ ☒ ☐ ☐

Police protection? ☐ ☐ ☐ ☒

Schools? ☐ ☐ ☐ ☒

Parks? ☐ ☐ ☐ ☒

Other public facilities? ☐ ☐ ☒ ☐

Discussion

The project is consistent with PDZ 87-1 and LDA MND as approved by the County, and will not trigger a significant new populations base, as the facility will bring 8-10 jobs to the area, some of which may bring people from out of the area, but overall this amount is not going to trigger new needs for public services.

Fire Services on site The Mariposa County Fire Department has jurisdiction over this site. In order to provide for fire protection onsite, the project includes a 110,000 gal fire water storage tank located in the southwest corner of parcel 4. Hydrants will be located as required by Fire department prior to final inspection. Fire truck access to the wood chip piles is along the 30 ft wide driveway and turn around at the end of the driveway. Fire truck access to the bioenergy facility is along the existing driveway that services parcel 4 and a hammer head turn around between the nitrogen storage tank and the engine generator building. By limiting the woodchip storage pile capacity to 24 days, the danger of spontaneous combustion of the woodchips is greatly minimized. Additionally, the Wood chip storage piles will meet California Fire Code specifications. Wood chip piles will not exceed 25 feet in height, 150 feet in width, and 250 feet in length per 2013 California Fire Code Section

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2808.3, or in the alternative in compliance with the CALFIRE Guidelines for storing logs during the tree mortality crisis, which is attached here as Attachment S. The Project will construct a 110,000 gallon tank and achieve all fire flow requirements and fire hydrants will be placed on the property as required by the local Fire agencies as well as compliance with state law relating to the storage of wood chips. All CALFIRE FireSafe standards must be met as applicable to the project and will be reviewed by CALFIRE at the time of construction permit review. Mitigation Measure 14.a.1 : Prior to grading or building permit issuance the Project plans shall include all details necessary to meet County Fire Department and CALFIRE requirements as applicable for fire protection including access, storage tank, hydrant location and a fire flow to meet applicable code requirements. Approval verification letters by County Fire and CALFIRE to Planning Director shall be required prior to grading and or building permit issuance. Monitoring for Mitigation Measure 14.a.1: County Fire and Planning Departments will conduct enforcement and monitoring of the mitigation measure through the construction permitting process.

XV. RECREATION Less Than Less Potentiall Significant Than y with No Significa Significa Mitigation Impact nt nt Impact Incorporatio Impact n a) Would the project increase the use of existing neighborhood and regional parks ☐ ☐ ☐ ☒ or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated? b) Does the project include recreational facilities or require the construction or expansion of recreational facilities that ☐ ☐ ☐ ☒ might have an adverse physical effect on the environment?

Discussion

The project will be located on private property zoned for industrial use. The project is consistent with PDZ 87-1 as developed by the County, and will not trigger any new needs for public recreation services.

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a) Would the project increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?

The project does not include any residential population which would affect recreational facilities; therefore, no impact is expected. b) Does the project include recreational facilities or require the construction or expansion of recreational facilities that might have an adverse physical effect on the environment? The project does not include recreation facilities or require the construction or expansion of recreational facilities. No impact is expected.

XVI. TRANSPORTATION/TRAFFIC -- Would the project: Less Than Potential Less Significant ly Than with No Significa Significa Mitigation Impact nt nt Incorporatio Impact Impact n a) Conflict with an applicable plan, ordinance or policy establishing measures of effectiveness for the performance of the circulation system, taking into account all modes of transportation including mass transit and non-motorized travel and ☐ ☐ ☒ ☐ relevant components of the circulation system, including but not limited to intersections, streets, highways and freeways, pedestrian and bicycle paths, and mass transit? b) Conflict with an applicable congestion management program, including, but not limited to level of service standards and travel demand measures, or other standards ☐ ☒ ☐ ☐ established by the county congestion management agency for designated roads or highways? c) Result in a change in air traffic patterns, including an increase in traffic levels or a ☐ ☐ ☐ ☒ change in location that results in substantial safety risks?

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d) Substantially increase hazards due to a design feature (e.g., sharp curves or ☐ ☒ ☐ ☐ dangerous intersections) or incompatible uses (e.g., farm equipment)? e) Result in inadequate emergency access? ☐ ☐ ☐ ☒ f) Conflict with adopted policies, plans, or programs regarding public transit, bicycle, or pedestrian facilities, or otherwise ☐ ☐ ☐ ☒ decrease the performance or safety of such facilities?

Discussion

The facility will operate 24 hours per day, seven days per week and will initially employ a fulltime staff of 10. This assumes 2 operators per 8 hour shift and 1 additional maintenance worker and 1 administrator. As operational experience is developed staffing requirements may be reduced to 6 or 7. During daytime hours, a maximum staff of 4 will be on site. A total of 5 parking spaces are proposed each 9 ft by 20 ft as indicated on the Preliminary Grading Plan (Attachment E). Public access is not anticipated.

A Traffic Study was conducted. (See Attachment P) Turning movement counts were collected at the intersection of CA-49 and Mykle Oaks Road/Gold Leaf Drive on April 25, 2017 during the morning (7-9 a.m.) and evening (3-6 p.m.) peak periods. It was observed that trucks made up 12.1% of traffic in the morning and 7.1% of traffic in the evening, although no trucks were observed traveling northbound out of the industrial park during either peak hour. Under existing conditions, the intersection performs well in both a.m. and p.m. peak periods, with vehicles experiencing only slight delay on average. The worst performing movement during both periods is northbound left/through/right, which operates at Level of Service (LOS) B during both a.m. and p.m. peak periods. Table 2 of the Traffic Study shows a comparison of average delay and level of service between existing conditions and existing plus project conditions.

Note: Total control delay for the worst movement is presented for stop-controlled intersection. Peak hour simulations were run using SimTraffic 10 software to assess any unexpected operational issues at the study intersection. Table 3 of the Traffic Study shows a comparison of average and 95th percentile queue lengths under both existing and existing plus project conditions. Expected queues of 0-1 vehicles represent conditions where there is occasionally one vehicle waiting to turn, but no more. The very low eastbound queue length and lack of any westbound queue indicate that the highway mainline operates well and experiences minimal delay due to turning vehicles. During simulations, turning vehicles frequently slowed down but did not come to a complete stop before making their turns. At no 99

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point were queues with two vehicles observed on CA-49. Gold Leaf Drive and Mykle Oaks Road both experienced average queues of one vehicle and 95th percentile queues of 2 vehicles during both a.m. and p.m. peak hours.

a) Conflict with an applicable plan, ordinance or policy establishing measures of effectiveness for the performance of the circulation system, taking into account all modes of transportation including mass transit and non-motorized travel and relevant components of the circulation system, including but not limited to intersections, streets, highways and freeways, pedestrian and bicycle paths, and mass transit?

Under existing plus project conditions, estimated project trips were added to the existing traffic in the study intersection. Based on the nature of the project, it was assumed that the vast majority of trips in and out would originate to the east of the project (90% to/from east, 10% to/from west), either within the community of Mariposa or via CA-140. Table 4 of the Traffic Study shows the trip distribution used. Project trips were then added to existing traffic volumes. Under existing plus project conditions, the intersection continues to perform well in both a.m. and p.m. peak periods with only a slight increase in overall delay. The worst performing movement remained northbound left/through/right. However, the average delay per vehicle for this movement fell from 11.4 to 11.1 seconds in the a.m. peak hour and from 10.8 to 10.3 seconds in the p.m. peak hour. This improvement is due to the increased proportion of vehicles turning right, which require gaps in eastbound traffic only in order to complete their turns.

Peak hour simulations of existing plus project conditions showed only small increases in queue lengths with the addition of project trips, as seen in Table 3 of the Traffic Study. There were minimal increases on the highway mainline, and small increases on Gold Leaf Drive, due to project traffic. The only approach that saw any increase in the number of vehicles waiting was westbound CA-49 in the a.m. peak hour, which has a 95th percentile queue length of only four feet. The project is not anticipated to produce any negative impacts on the intersection with respect to queueing or excessive delays. See the Traffic study to review relevant figures and tables.

It should also be noted that the proposed Project would divert trucks from elsewhere on CA-49 and reduce their distance traveled. Currently, trucks hauling chips and other woody biomass from forest thinning operations must travel to Fresno, Sonora, or farther in order to access a willing recipient for the biomass. For trucks hauling chips from Sierra National Forest via CA- 140 or CA-49, this is a reduction of 75 miles or more each way. This project could therefore result in downstream benefits at higher-volume segments and intersections along CA-49.

b) Conflict with an applicable congestion management program, including, but not limited to level of service standards and travel demand measures, or other standards established by the county congestion management agency for designated roads or highways?

The proposed Project would increase traffic through the intersection of CA-49 and Mykle Oaks 100

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Road/Gold Leaf Drive by seven trips during the a.m. peak hour and seven trips during the p.m. peak hour, a change of less than three percent. This is a small change in traffic volume and would have virtually no impact on the level of service of the study intersection. Simulations run using peak hour volumes indicated that the project would also have minimal impact on queueing. However, it appears that the study intersection does exhibit significant fatigue cracking across the Gold Leaf Drive approach, which would be exacerbated by an increase in heavy vehicles entering and exiting the industrial park.

Mitigation Measure 16.b.1.: Gold Leaf Drive approach improvements shall be improved to meet minimum road surface requirements for the approach prior to Certificate of Occupancy for the project. CALTRANS and/or County Encroachment Permits shall be required as applicable prior to grading or building permit issuance.

Monitoring for Mitigation Measure 16.b.1.: This mitigation measure will be monitored by the Mariposa County Planning Department through the project construction permitting process c) Result in a change in air traffic patterns, including an increase in traffic levels or a change in location that results in substantial safety risks? The project does not include any air traffic and is not expected to have any effect on air traffic patterns. There is no impact. d) Substantially increase hazards due to a design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)?

Caltrans has expressed concerns about the safety of large truck access on CA-49 and requested a more detailed assessment of turning operations. Three of the four turning operations analyzed at the intersection can be accomplished safely without any operational hazards. The fourth constitutes a safety hazard based on Caltrans design guidelines. Given the small number of large trucks added to the northbound approach and the absence of any such trucks observed under existing conditions, actual conflicts seem unlikely under current low traffic levels. If traffic levels on CA-49 were to increase significantly, these concerns could be exacerbated. Widening the approach at Gold Leaf Drive and increasing the radius of the southeast corner would eliminate any such potential conflicts. The project has agreed to do so. The following mitigation measure will reduce potential impacts to less than significant levels.

Mitigation Measure 16.d.1.: Gold Leaf Drive approach radius improvements improvements shall be improved to meet CALTRANS requirements for the approach prior to Certificate of Occupancy for the project. A CALTRANS Encroachment Permit shall be required prior to grading or building permit issuance. All encroachment improvements shall be completed prior to issuance of a Certificate of Occupancy for the facility.

Monitoring for Mitigation Measure 16.d.1.: This mitigation measure will be monitored by the Mariposa County Planning Department through the project construction permitting process.

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e) Result in inadequate emergency access?

The layout of the industrial park and current site plan were analyzed to determine whether the project site could accommodate the types of vehicles expected to access it, including emergency vehicles. The analysis utilized the same tractor-trailer design vehicle as above. This design vehicle represents large chip trucks, which must back into the site in order to dump their contents into the feedstock holding area. Within the park and on site at the biomass plant, these vehicles would be free to make 2- or 3-point turns without concern for conflicting traffic traveling at high speed. At the end of Gold Leaf Drive, next to the feedstock holding area, the road widens to approximately 90 feet. This is more than sufficient for a tractor-trailer to turn around. The project site is not expected to experience any operational deficiencies in terms of emergency access. f) Conflict with adopted policies, plans, or programs regarding public transit, bicycle, or pedestrian facilities, or otherwise decrease the performance or safety of such facilities?

The proposed project does not affect, in any way, adopted policies, plans or programs supporting alternative transportation.

XVII. TRIBAL CULTURAL RESOURCES -- Would the project:

Less Than Potentia Less Significant lly Than with No Significa Significa Mitigation Impact nt nt Incorporatio Impact Impact n a)Would the project cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of the size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is: i) Listed or eligible for listing in the California Register of Historical ☐ ☐ ☐ ☒ Resources, or in a local register of historical resources as defined in 102

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Public Resources Code section 5020.1(k), or ii) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Public Resources Code Section 5024.1. In applying the criteria set forth in ☐ ☐ ☒ ☐ subdivision (c) of Public Resource Code Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

Discussion a i) and ii)

This project will not cause a substantial adverse change in the significance of a tribal cultural resource as defined in Public Resource Code Section 21074 because no tribal resources have been identified on site. Public Resources Code requires lead agencies to consult with any California Native American tribe that requests consultation and is traditionally and culturally affiliated with the geographic area of the proposed project to help determine whether a project may have a significant effect on a tribal cultural resource.

Tribal resources are defined as, “Sites, features, places, cultural landscapes, sacred places, and objects with cultural value to a California Native American tribe that either, (A) included or determined to be eligible for inclusion in the California Register of Historical Resources or (B) included in a local register of historical resources as defined by subdivision (k) of Section 5020.1.(2) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Section 5024.1 for the purpose of this paragraph, the lead agency shall consider the significance of the resource to a California Native American Tribe.

A current study available in the project file at the County Planning Department, was completed under the provisions of CEQA. Section 21083.2 of the statute and Section 15064.5 of the CEQA Guidelines provide instructions for a lead agency to consider the effects of Projects on historical resources and cultural resources.

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Compliance with state law is enough to ensure protection of any unexpected remains that however unlikely may be found at the site, so no impact is expected and no mitigation is required, however, through consultation with tribal groups pursuant to PRC 21080.3.1 & 2 a recommendation for monitoring during excavation activities was made. (Also see Section V. CULTURAL RESOURCES of this Initial Study.) The project has agreed to include the following mitigation as is referenced in the preceding section V. Cultural Resources, Mitigation 5. d. 1 as follows:

Mitigation 5 d.1 A Native American monitor shall be on-site for the duration of ground disturbance. During road grading, soil testing and/or construction, or any activity that involves ground disturbance necessary to implement project conditions of approval, if any signs of prehistoric, historic, archaeological, paleontological resources are evident, all work activity within fifty feet of the find shall stop and the Mariposa County Planning Department shall be notified immediately. No work shall be done within fifty feet of the find until Planning has identified appropriate measures to protect the find and those measures have been implemented by the applicant. Protection measures for the site may include, but not be limited to, requiring the applicant to hire a qualified archaeologist who shall conduct necessary inspections and research, and who may supervise all further ground disturbance activities and make any such recommendations as necessary to ensure compliance with applicable regulations. In addition to the Planning Department, the Mariposa County Coroner and the Native American Heritage Commission shall be notified should human remains be discovered. If the remains are determined by the Native American Heritage Commission to be Native American, the NAHC guidelines shall be adhered to in treatment and disposition of the remains. Representatives of the Most Likely Descendant shall be requested to be on-site during disturbance and/or removal of human remains.

Monitoring for Mitigation Measure 5.d.1: The applicant or his on-site designee shall be responsible for ensuring compliance with this mitigation. Based on the incorporation of this mitigation measure into the approval for this project, the project will have a less-than- significant impact on cultural resources.

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XVIII. UTILITIES AND SERVICE SYSTEMS -- Would the project: Less Than Less Significant Potentially Than with No Significant Significa Mitigation Impact Impact nt Incorporatio Impact n a) Exceed wastewater treatment requirements of the applicable Regional ☐ ☐ ☐ ☒ Water Quality Control Board? b) Require or result in the construction of new water or wastewater treatment facilities or expansion of existing ☐ ☐ ☒ ☐ facilities, the construction of which could cause significant environmental effects? c) Require or result in the construction of new storm water drainage facilities or expansion of existing facilities, the ☐ ☐ ☒ ☐ construction of which could cause significant environmental effects? d) Have sufficient water supplies available to serve the project from existing entitlements and resources, or ☐ ☐ ☒ ☐ are new or expanded entitlements needed? e) Result in a determination by the wastewater treatment provider, which serves or may serve the project that it has ☐ ☒ ☐ ☐ adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments? f) Be served by a landfill with sufficient permitted capacity to accommodate the ☐ ☐ ☐ ☒ project’s solid waste disposal needs? g) Comply with federal, state, and local statutes and regulations related to solid ☐ ☐ ☐ ☒ waste?

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a) Exceed wastewater treatment requirements of the applicable Regional Water Quality Control Board?

The Project does not produce any appreciable amount of waste water, and provision for waste water disposal is subject to Mariposa County Health Code requirements and applicable state law governing the shared septic system proposed for use by the project. With the limited wastewater generation and the application of the existing requirements, no impact is expected. b) Require or result in the construction of new water or wastewater treatment facilities or expansion of existing facilities, the construction of which could cause significant environmental effects?

The Project’s wastewater treatment needs were adequately analyzed in the LDA MND, and this project is consistent with such analysis. The current septic system on Parcel 4 has sufficient capacity for the expected 8-10 employees, and room for up to ten more users. There is also the additional septic easement that could be used in the future, that is being moved from Parcel 3 to Parcel 4 as discussed further below. The project implementation will have a less than significant impact on existing septic facilities. Applicable State Drinking Water standards and Division of Drinking Water requirements for the water system permitting is sufficient to address any potential impact to less than significant levels.

The project proposes to use the existing well for water, however, the proposed increase of the water use of the existing water system may have the potential to cause significant environmental effects and, therefore, the use of the water well to serve the water demand was analyzed.

The completion report (No. 0930872) for the subject well shows the well to be 200 feet deep and taps four water-producing fractured quartz zones between 75 and 160 feet in depth. The well was constructed in March 2007 by Mariposa Well Drilling Co., Inc. On March 17, 2017, the static water level was 15 feet deep and the yield was 15 gpm after two hours of airlifting.

Mariposa Well Drilling Co., Inc. conducted a six-hour constant discharge on the well on Sep•tember 27, 2017. The static water level was 29 feet deep, and was expected to be deeper than the earlier measurement, which was made in the spring, when water levels are normally shallower. The well was pumped at an average rate of 15 gpm. At the end of the pumping period, the pumping level was 76 feet. The drawdown was 47 feet and the specific capacity was 0.3 gpm per foot. Copies of the pump test measurements are attached.

A semilog plot of the drawdown measurements indicated a trans•missivity of 65 gpd per foot. Water-level recovery was measured for 22 minutes after pumping stopped, when full recovery was at•tained. A semilog plot of uncorrected recovery also indicated a 106

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transmissivity of 65 gpd per foot. Copies of the plots are attached. The equation used is found in the attached Hydrology Report, Attachment M. The report found that there is sufficient water to serve the project demand for all facilities and operations, therefore a less than significant is expected. c) Require or result in the construction of new storm water drainage facilities or expansion of existing facilities, the construction of which could cause significant environmental effects?

According the LDA MND, the construction of new storm water drainage facilities as part of the roadway is considered a minor element of the required road improvements and is necessary to minimize erosion. The access to the proposed project site is was completed and the project itself incorporates minimal grading to accommodate approximately 8600 square feet of new structures being approximately 4% of the 5.27 acres site. Additionally, the development of the site will be completed as shown on the Grading Plan, Attachment E where site grading is minimized These design features of the Project will be required through existing county processes, and state law to comply with the National Pollution Discharge Elimination System (NPDES) and are required to submit a Stormwater Pollution Prevention Plan for construction activities prior to the issuance of grading or building permit for the project to minimize any environmental affects created through construction including any drainage facilities. The project analysis included storm water runoff calculations and includes the installation of new storm water storage tank and metering as a part of the project design in order to manage the increase runoff potential and minimize impacts of discharge to less than significant levels. (Attachment E-Preliminary Grading Plan) Due to the requirements of the project to comply with existing regulatory requirements for grading and stormwater management, the new stormwater retention/storage system design and the limited grading and site disturbance activities involved with the project design, a less than significant impact is expected. d) Have sufficient water supplies available to serve the project from existing entitlements and resources, or are new or expanded entitlements needed?

As described in item b) above, the project does not need any new water supply entitlements as water supply was evaluated for the project as outlined in the Hydrology Report, Attachment M. The report found that there is sufficient water to serve the project demand for all facilities and operations, therefore a less than significant is expected.

e) Result in a determination by the wastewater treatment provider, which serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments?

Parcel 2 of the subdivision, if ever developed, relies on a future septic system that may be located on an existing septic system easement that is currently located on Parcel 3. In order to develop Parcel 3 in a way that can be useful for the facility (chip storage), the septic

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system and the associated expansion easement abandonment is required and a new easement location for a future septic system must be established.

County Environmental Health Department has conducted an evaluation of the proposed sewage system easement relocation form Parcel 2 to Parcel 4 (Project site) of the subdivision including soil profile holes for a future septic system and found the soils to be suitable and relocation of the septic system easement can be achieved. The Project will cover the relocation costs associated with the movement of the system easement, from Parcel 3 to Parcel 4, where the system can be placed in a location that works for the new facility. The Project has obtained the permission of the adjacent property owner of Lot 2, and the owner of Lot 3 that reflects their consent to move the septic easements as described in the Grading Plan. County Environmental Health determined that the proposed location is acceptable, see Attachment T, and the letters of approval by the property owners at Attachment U. The Project will also pay for the new Parcel Map or other documents as may be required to be drafted and "Declaration of Property owner's Association Document" that will be attached to that Map, and cover any filing and recording fees associated with that document. With the application of mitigation there is a less than significant impact.

Mitigation Measure 18 e.1.: Prior to grading or building permit issuance, the relocation of the septic easement as shown on the grading plan and site plan must be completed and recorded to the satisfaction of the County Health Department- Environmental Health Division, County Surveyor and Planning Director.

Monitoring for Mitigation Measure 18 e.1.: Enforcement and monitoring will be by the County Health Planning and Public Works Departments through the construction permit permitting process. f) Be served by a landfill with sufficient permitted capacity to accommodate the project’s solid waste disposal needs?

The project is investigating the possibility of purchasing woodchips from the landfill to supplement the county’s need to divert more waste material away from the landfill in response to California’s 75% diversion goal. The county is also faced with the future possibility of having to close the landfill and haul garbage to another location such as Merced. The bioenergy project can utilize up to 2,400 dry tons per year of non-forest wood waste such as residential green waste. This material could be collected in Merced and back hauled to Mariposa and sold to the bioenergy facility. Should the county go forward with the marketable compost operation at the landfill, the project has been advised that the compost process needs approximately 1 ton per day of ash. The project might be able to support this requirement by providing wood ash from the bioenergy project. 108

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The project is served by the County landfill that is adequately licensed and can accept nonhazardous ash. More about the ash is described below, as well as the only other solid waste expected to be produced on site: which is a water, sawdust and ash mixture, referred to as a sludge residue. g) Comply with federal, state, and local statutes and regulations related to solid waste?

The Project will comply with all solid waste laws. Two disposal outputs, non-hazardous ash and sludge will be taken to the Mariposa County Landfill or an appropriately permitted waste facility.

As approximately 650 tons of ash will be produced at the site per year. Ash produced from forest residue does not contain the contaminants under 22 CCR 66261.30. Also, to be cautious, and to potentially qualify for the Cal Recycle “Biomass Diversion Credit” at the local landfill, regular monitoring of ash will be required on a monthly basis to ensure that the ash does not contain hazardous material under state law, as defined under 22 CCR 66261.30. Note that this law requires self-regulation: it is up to the ash producer to regularly test the ash to ensure its quality under 22 CCR 66260.200. Concerns about Ash The Mariposa Biomass Project proposed facility will turn sustainably harvested wood waste from High Hazard Zones associated with Tree Mortality into clean green renewable energy. One of the byproducts of the woody biomass-to-bioenergy conversion process is ash. The sources of the woody biomass, the chemical composition of that ash, how much ash will be produced and potential beneficial uses of the ash are discussed below. The bottom line is that even though the biomass plant will “burn” the woody biomass in several optimized stages, that process does not change the nature of the ash produced from if that same wood was burned in the forest, in a fireplace or in an air curtain burner. The only difference might be that the more complete combustion afforded the Cortus WoodRoll® will mean that the ash will contain less char or organic material and produce far less air pollution than if the combustion was at a lower temperature and/or was less complete.

What is the Chemical Composition of Wood Ash? When a tree or a plant grows, it uses photosynthesis to convert carbon dioxide in the air to carbohydrate molecules (e.g. sugars) that are used to create wood, an organic fibrous structural tissue of cellulose embedded in a matrix of lignin. Wood is therefore largely composed of organic molecules (the cellulose and lignin) that contain roughly equal number of carbon and hydrogen atoms as well as oxygen atoms. By weight wood is typically 50% carbon, 42% oxygen, 6% hydrogen, and 1% other elements such as the minerals, calcium, potassium sodium, magnesium, iron and manganese. These minerals are taken up by the roots of the tree with the water it gets from the ground and most, if not all of these minerals are necessary for health growth of trees or plants in general.

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See Table Q: The Translocation of Minerals in Trees

Table Q

When wood or woody biomass is burned, the organic components (carbon, hydrogen and oxygen) are converted by the combustion process to carbon dioxide and water which are released as gases. The minerals in the wood however, are largely left behind as ash. While the chemical composition of the ash can vary somewhat depending on the species of tree, limbs vs. needles, and the combustion temperature, the composition of wood ash almost always regarded as an important source of nutrients, Calcium (Ca), Potassium (K), Magnesium (Mg), Phosphorus (P), Manganese (Mn), Iron (Fe) and Aluminum (Al). The figure on the previous page is from a paper, “Physical, chemical and hydrological properties of Ponderosa pine ash”, attached, by a geology professor (Gabet, et al) at San Jose State University that examines the chemical composition of ash from Ponderosa Pine collected in Montana. The I-90 ash was collected from an area affected by a large wildfire off I-90. The other measurements were from ash burned in the laboratory at two different temperatures. They chose ponderosa pine as it was “a conifer that is widespread throughout the fire-prone mountainous regions of western North America.”, and is certainly representative of much of the wood our biomass plant will be seeing for the foreseeable future.

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Table R

The table above is from a paper by Prof. Misra, et al, University of Wisconsin - Madison, that examined the chemical composition of ash from several different species of trees. See attached “WOOD ASH COMPOSITION AS A FUNCTION OF FURNACE TEMPERATURE”. As can be seen in the figure above, although there is variation in the ash composition for the various species, calcium, potassium, phosphorus and magnesium and manganese are found at significant concentrations in all the tree species tested similar to the results from ponderosa pine from Montana.

Typically, wood ash contains only minimal amounts of heavy metals from the soils, but to assure the quality and non-toxic nature of the ash produced we proposed having the ash produced chemical analyzed once a month to assure that no source of toxins of heavy metals has found a way into the fuel supply and therefore the ash produced by the plant.

The Source of the Fuel or Woody Biomass Used by the Facility The Mariposa Biomass Plant expects to obtain a Power Purchase Agreement (PPA) with PG&E at a favorable price. The BioMAT program and auction process via which the PPAs are obtained were defined by Senate Bill 1122, passed in 2012, and along with the provisions in the Governor’s Tree Mortality Proclamation (Oct 30, 2015) are meant to facilitate small-scale local biomass plants located near fuel sources in an effort to promote rural economies as well as remove dangerous fuel from what are identified as High Hazard Zones around public infrastructure.

The short-term financial viability of the Mariposa Biomass Project depends on the favorable rates afforded by the BioMAT program that requires that at least 80% of the fuel we use comes from sustainably harvested timber operations that typically require a timber harvest plan developed by a Registered Professional Forester. Currently, as a result of the 111

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Tree Mortality Disaster, homeowners can also get an exemption that allows removal of dead or dying trees from their property. The $5 million EPIC grant from the California Energy Commission that the Mariposa Biomass Project expects to be awarded will to help pay for the installation of the plant also requires that the fuel used comes from the Cal Fire identified High Hazard Zones of dead trees in our local area. Thus, by requiring that our fuel suppliers meet the requirement of S.B. 1122 the Governor’s Proclamation, and the requirements of the EPIC grant, we can be assured that our fuel will come from forests and trees removed around public infrastructure and homes, as will not contain domestic or construction waste – thus assuring that the ash produced by the plant will come from clean forest waste that has not been treated or otherwise contaminated.

How much Ash will the Biomass Facility produce? TABLE S It is generally stated that when wood is burned roughly 0.5 to 1.5% of the mass or weight of the wood will remain behind as ash. The actual amount depends on the species of tree from which the biomass was derived and whether it is wood or bark that is being burned. Burning bark can produce as much 3- 4% ash. The table on the right is from the paper by Misra. That paper also found that when the ash produced at lower temperature was subjected to higher temperatures, the mass of the ash was reduced by 23 to 48% as carbon in the form of carbonates was driven off and replaced by oxides and hydroxides.

The Cortus WoodRoll® process will use 35-37 Bone Dry Tons (BDT) of woody biomass a day. Using the above averages, it might be expected that the process would produce approximately 0.5 tons of ash a day (1.5% of 35 tons). However, given that it is inevitable that some dirt or sand will be captured as the fuel is handled at the source and at our site, we estimate that the plant could produce up to 1.5 tons of ash per day.

Beneficial Uses of Wood Ash It has long been known that wood ash has numerous beneficial uses in the garden and agriculture. See the attached “Agricultural Uses of Wood Ash in California”.

Because wood ash contains oxides and hydroxides of Calcium, i.e. lime, it is often used to neutralize soil acidity. Wood ash also provides the macro nutrient potassium, or potash, as well as the secondary and micronutrients sulfur, calcium, and magnesium, boron, cobalt, copper, iron, manganese, molybdenum and zinc. It is anticipated that the County Solid Waste facility could incorporate ash from the biomass facility in their composting operation. See attached abstract for “Wood Ash as an Amendment in Municipal Sludge And Yard Waste Composting Processes”. Cal recycle also lists ash as an acceptable alternative daily cover - 27 CCR 20690.

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Other uses of wood ash include use in concrete formulations as can be seen in the attached paper titled, “The incorporation of wood waste ash as a partial cement replacement material for making structural grade concrete: An overview”. To the extent that we produce more ash than the County Solids Waste facility can use either for compost or alternative daily cover, we may be able to sell it to our neighbor in the industrial park, Outback Materials, for use in cement.

Overall the wood ash the biomass plant produces could be put to beneficial use rather than disposed of in the landfill.

Sludge Composition

The Mariposa Biomass Project utilizes the Cortus WoodRoll® process to convert woody biomass in the form of wood chips, to electrical energy by generation of a synthetic gas (sysgas) for use in a reciprocating (piston engine) linked to a generator. One of the advantage of the WoodRoll® process is an integral drying stage that allow the use of fuels of widely varying moisture content. Moisture from this drying stage can be condensed for use as process water in a later stage of the WoodRoll® process, and any moisture in the syngas can also be condensed, again for use as process water.

As wood chips typically contain wood dust, the condensate from the drying stage will contain that dust as solid material which can be separated from the process water as a sludge in form of sludge cakes. The chemical composition of that sludge will obviously depend on the chemical composition of the fuel source, but the most likely familiar description of the solids in the sludge is sawdust with both the organic materials, e.g., lignin and cellulose, and minerals. The minerals in the sludge will resemble the minerals in the ash, discussed separately and most metals will be in the form of metal hydroxides that will give the sludge mildly alkaline pH of 8. 5 - 9, similar to baking soda which has a pH of 9 in water. We expect to use 35 Bone Dry Tons (BDT) a day of fuel and generate 60 pounds of sludge a day (< 0.1%) that will be 60-70% water.

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From a regulatory point of view, this sludge was compared to the two Sections of State law that govern the definition of Hazardous Waste, § 66261.31. Hazardous Wastes from Non- Specific Sources and § 66261.32. Hazardous Wastes from Specific Sources. § 66261.31 lists hazardous waste from a variety of industrial sources that include various industrial solvents and sludge form plating and petroleum processing. There is no overlap in the description of hazardous wastes in those regulations with the chemical composition of the sludge generated by the Cortus WoodRoll® process. § 66261.32 is related to a list of chemical conversion processes that do not include biomass conversion. The sludge produced is not a hazardous waste as defined under California law.

Typical Chemical Composition of Sludge from the Cortus WoodRoll® Process

Table R: Chemical Composition of Sludge, more is available within Attachment Q, “Rough Indicative Condensate Sludge Data”.

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XIX. MANDATORY FINDINGS OF SIGNIFICANCE Less Than Less Potentiall Significant Than y with No Significa Significan Mitigation Impact nt t Impact Incorporatio Impact n a) Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self- sustaining levels, threaten to eliminate a ☐ ☒ ☐ ☐ plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or prehistory? b) Does the project have impacts that are individually limited, but cumulatively considerable? (“Cumulatively considerable” means that the incremental effects of a project ☐ ☐ ☐ ☒ are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects)? c) Does the project have environmental effects, which will cause substantial ☐ ☐ ☐ ☒ adverse effects on human beings, either directly or indirectly?

Discussion & Conclusions: 1. The project has the potential to impact biological and cultural resources utilities, noise and air quality. Mitigation measures are proposed to reduce these potentially significant impacts to less than significant levels. Mitigation measures are proposed to reduce these potentially significant impacts to less than significant levels.

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2. The project will result in increased air emissions, groundwater use, noise and traffic. However, these impacts are not considered to be significant, are individually limited, and not cumulatively considerable.

3. The project does not have the potential to cause substantial adverse effects on human beings, either directly or indirectly.

Based upon the environmental review conducted within this Initial Study, and the anticipated level of impact as a result of the project, a subsequent mitigated negative declaration will be adopted for the project.

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