AZUSA HYDROELECTRIC PIPELINE SEISMIC RETROFIT PROJECT Final Initial Study / Mitigated Negative Declaration

AZUSA HYDROELECTRIC PIPELINE SEISMIC RETROFIT PROJECT Final Initial Study / Mitigated Negative Declaration

AZUSA HYDROELECTRIC PIPELINE SEISMIC RETROFIT PROJECT Final Initial Study / Mitigated Negative Declaration Prepared for January 2013 Pasadena Water & Power AZUSA HYDROELECTRIC PIPELINE SEISMIC RETROFIT PROJECT Final Initial Study / Mitigated Negative Declaration Prepared for January 2013 Pasadena Water & Power 626 Wilshire Boulevard Suite 1100 Los Angeles, CA 90017 213.599.4300 www.esassoc.com Oakland Orlando Palm Springs Petaluma Portland Sacramento San Diego San Francisco Santa Cruz Seattle Tampa Woodland Hills 120288 TABLE OF CONTENTS Azusa Hydroelectric Pipeline Seismic Retrofit Project Final Initial Study / Mitigated Negative Declaration Page Environmental Factors Potentially Affected ........................................................................2 Project Description ...............................................................................................................3 Project Location ..............................................................................................................3 Project Characteristics ...................................................................................................3 Environmental Impacts .........................................................................................................8 Aesthetics........................................................................................................................8 Agricultural and Forest Resources ..............................................................................10 Air Quality......................................................................................................................11 Biological Resources ....................................................................................................13 Cultural Resources .......................................................................................................16 Geology and Soils ........................................................................................................20 Greenhouse Gas Emissions ........................................................................................24 Hazards and Hazardous Materials ..............................................................................25 Hydrology and Water Quality .......................................................................................27 Land Use and Planning ................................................................................................30 Mineral Resources ........................................................................................................31 Noise .............................................................................................................................32 Population and Housing ...............................................................................................35 Public Services .............................................................................................................36 Recreation .....................................................................................................................37 Transportation and Traffic ............................................................................................38 Utilities and Service Systems .......................................................................................41 Mandatory Findings of Significance .............................................................................43 Appendices A. Biological Resources Reports B. Cultural Resources Report C. Response to Comments D. Mitigation Monitoring and Reporting Program Figures and Tables Figure 1 Regional Location ........................................................................................... 6 Figure 2 Project Location .............................................................................................. 7 Table 1 Road Segments Utilized by Construction Workers ........................................ 39 Table 2 Cumulative Projects List ..................................................................................44 Azusa Hydroelectric Pipeline Seismic Retrofit Project I ESA / 120288 Final Initial Study/Mitigated Negative Declaration January 2013 ENVIRONMENTAL CHECKLIST FORM 1. Project Title: Azusa Hydroelectric Pipeline Seismic Retrofit Project 2. Lead Agency Name and Address: City of Pasadena Pasadena Water and Power 85 East State Street Pasadena, CA 91105 3. Contact Person and Phone Number: Jason Miller, P.E. 626.744.6276 4. Project Location: 1850 N. Ranch Road City of Azusa, CA 5. Project Sponsor’s Name and Address: City of Pasadena Pasadena Water and Power 85 East State Street Pasadena, CA 91105 6. General Plan Designation: Open Space 7. Zoning: OS – Open Space 8. Description of Project: The City of Pasadena owns and operates an existing hydroelectric plant located in the City of Azusa, approximately three miles northeast of the intersection of Interstate (I) 605 and I-210. The plant facilities include two above ground hydroelectric pipelines that are used to create hydropower. Both are aged and require structural retrofitting in order to enhance their resistance to damage and failure during a seismic event. Under the proposed project, the City of Pasadena would provide the appropriate structural upgrades to the existing pipeline facilities. The project would not expand the footprint of the facility or capacity of the pipelines, nor would it increase the number of personnel servicing the project site on an operational basis. 9. Surrounding Land Uses and Setting: The project is surrounded by open space to the north and east of the pipelines, and residential uses to the south and west of the project site. 10. Other public agencies whose approval is required: Federal Energy Regulatory Commission (FERC) Azusa Hydroelectric Pipeline Seismic Retrofit Project 1 ESA / 120288 Final Initial Study/Mitigated Negative Declaration January 2013 Project Description Project Location The proposed project is located in the eastern portion of Los Angeles County, in the City of Azusa, approximately 20 miles northeast of downtown Los Angeles. The project site is in the northern portion of the City, just south of the Angeles National Forest and San Gabriel River. The site is located approximately three miles northeast of the intersection of Interstate (I-) 605 and I-210, as shown in Figure 1. Access to the site is from I-210, via North Azusa Drive to Ranch Road; conversely from Ranch Road to North San Gabriel Canyon Road to I-210 (Figure 2). The project site is located in a suburban area with surrounding residential uses and open space. The project site is designated in the City of Azusa’s General Plan as Open Space and is directly adjacent to land designated as open space and low-density and moderate-density residential. The San Gabriel River is located approximately 0.3 mile north from the project site. Project Characteristics The City of Pasadena owns and operates an existing hydroelectric plant located in the City of Azusa. There are two above ground pipelines associated with the hydroelectric plant; one is the Penstock, a 38-inch welded steel pipe installed in 1948; and the other is the Spillway Bypass pipeline, a 36-inch reinforced concrete pipe installed in the 1930s. These pipelines are located adjacent to the plant and atop two ridges. The pipelines are fed by a forebay, which is a reservoir that channels the water into the pipes, at the top of the hill from which these ridges run down. Both pipelines are aged, have structural deficiencies, and require structural retrofitting in order to enhance their resistance to damage and reduce the possibility of failure during a seismic event. The City of Pasadena is proposing to undertake the appropriate structural upgrades to the existing pipeline facilities only. These upgrades would occur “in kind” to existing infrastructure. The proposed project would not expand the existing footprint of the facility or capacity of the pipelines, nor would it increase the number of personnel servicing the project site on an operational basis. Also, the project would not increase the generation capacity of the facility nor would it increase the amount of water used to run the generator. Construction staging would also occur within existing disturbed areas, and no staging activity would occur in the adjacent open space areas. Penstock The Penstock is a 38-inch inside diameter welded steel pipe installed in 1948. The pipeline is supported by steel rings and concrete blocks. The Penstock Pipeline measures approximately 800\ feet from where it exits the forebay to where it enters the powerhouse, dropping 390 feet in elevation. Where it is above ground, the Penstock is supported on 19 steel ring supports on rockers which in turn are supported on 5-foot wide concrete anchor blocks embedded into the Azusa Hydroelectric Pipeline Seismic Retrofit Project 3 ESA / 120288 Final Initial Study/Mitigated Negative Declaration January 2013 hillside. The visible segment of the Penstock within the project area measures approximately 500 feet in length. Several of the Penstock concrete supports have become substantially exposed due to erosion and other supports have become buried with debris to the point that supports have become locked up and do not work properly to allow unrestricted thermal expansion or contraction of the pipe. The pipeline is currently operating without material leakage; however, some of its pipe supports have rotated and at least one support is near collapse. Collapse

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