CEQA Initial Study And Mitigated Negative Declaration Summer Flow Augmentation of Malibu Creek January 2019 Prepared by: Las Virgenes – Triunfo Joint Powers Authority 4232 Las Virgenes Road Calabasas, California 91302 Technical Assistance Provided by: Stantec Consulting Services Inc. 300 North Lake Avenue, Suite 400 Pasadena, California 91101 Table of Contents Section Name Page Number Section 1 Project and Agency Information .............................................................................. 1-1 1.1 Project Title and Lead Agency .................................................................................... 1-1 1.2 Project Background and Objectives ............................................................................. 1-1 1.2.1 Project Background ................................................................................................. 1-2 1.2.2 Project Objective ..................................................................................................... 1-2 1.3 Project Location and Environmental Setting ............................................................... 1-3 1.4 Project Description....................................................................................................... 1-3 1.4.1 Conveyance Pipeline ............................................................................................... 1-3 1.4.2 Water Treatment ..................................................................................................... 1-4 1.4.3 Construction ............................................................................................................ 1-6 1.4.4 Operations ............................................................................................................... 1-6 1.5 Public Agency Review and/or Approval ..................................................................... 1-6 Section 2 Environmental Analysis ............................................................................................ 2-1 2.1 Environmental Factors Potentially Affected ................................................................ 2-1 2.2 Agency Determination ................................................................................................. 2-1 2.3 Environmental Checklist .............................................................................................. 2-2 2.3.1 Aesthetics ................................................................................................................ 2-2 2.3.2 Agricultural and Forest Resources .......................................................................... 2-3 2.3.3 Air Quality .............................................................................................................. 2-4 2.3.4 Biological Resources ............................................................................................ 2-10 2.3.5 Cultural Resources ................................................................................................ 2-19 2.3.6 Geology and Soils ................................................................................................. 2-23 2.3.7 Greenhouse Gas Emissions ................................................................................... 2-25 2.3.8 Hazards and Hazardous Materials ........................................................................ 2-29 2.3.9 Hydrology and Water Quality ............................................................................... 2-31 2.3.10 Land Use and Planning ......................................................................................... 2-34 2.3.11 Mineral Resources ................................................................................................ 2-37 2.3.12 Noise ..................................................................................................................... 2-38 2.3.13 Population and Housing ........................................................................................ 2-44 2.3.14 Public Services ...................................................................................................... 2-45 2.3.15 Recreation ............................................................................................................. 2-46 2.3.16 Transportation and Traffic .................................................................................... 2-47 2.3.17 Tribal Cultural Resources ..................................................................................... 2-50 2.3.18 Utilities and Service Systems................................................................................ 2-52 2.3.19 Mandatory Findings of Significance ..................................................................... 2-54 Section 3 References, Abbreviations and Report Preparation .............................................. 3-1 3.1 References and Bibliography ....................................................................................... 3-1 3.2 Acronyms and Abbreviations ...................................................................................... 3-6 3.3 Preparers of the Initial Study ....................................................................................... 3-9 Summer Flow Augmentation of Malibu Creek Page i Initial Study January 2019 Table of Contents Table Name Page Number Table 1 SCAQMD Air Quality Significance Thresholds .......................................................... 2-5 Table 2 Estimated Peak Day Construction Air Pollutant Emissions ......................................... 2-7 Table 3 Estimated Fugitive Dust Emissions .............................................................................. 2-8 Table 4 Localized Significance Threshold Analysis Before Mitigation .................................... 2-8 Table 5 Estimated Annual Construction Air Pollutant Emissions ........................................... 2-27 Table 6 Estimated Annual GHG Emissions from Project Construction .................................. 2-28 Table 7 Los Angeles County Construction Noise Ordinance .................................................. 2-40 Table 8 Construction Equipment Noise Levels ....................................................................... 2-42 Figure Name Page Number Figure 1 Location Map................................................................................................................ 1-8 Figure 2 Area Plan ...................................................................................................................... 1-9 Figure 3 Pipeline Alignment ..................................................................................................... 1-10 Figure 4 View Under LA County Bridge: Method of Pipe Mounting ...................................... 1-10 Appendices A Biological Resources Technical Report B Cultural Resources Technical Report C Native American Consultation Summary Table Page ii Summer Flow Augmentation of Malibu Creek January 2019 Initial Study Section 1 Project and Agency Information 1.1 PROJECT TITLE AND LEAD AGENCY Project Title: Summer Flow Augmentation of Malibu Creek Lead Agency Name: Las Virgenes – Triunfo Joint Powers Authority Lead Agency Address: 4232 Las Virgenes Road, Calabasas, CA 91302-1994 Contact Person: Mr. Brett Dingman Contact Phone Number: (818) 251-2330 Project Sponsor: Same as Lead Agency 1.2 PROJECT BACKGROUND AND OBJECTIVES The Las Virgenes Municipal Water District (LVMWD) provides potable water, wastewater treatment, recycled water and biosolids composting to more than 75,000 residents in the cities of Agoura Hills, Calabasas, Hidden Hills, Westlake Village, and unincorporated areas of western Los Angeles County. The Triunfo Sanitation District serves approximately 33,000 residents of east Ventura County, including Oak Park, Lake Sherwood, Bell Canyon, and the Westlake Village and North Ranch portions of Thousand Oaks. In 1964, the Las Virgenes - Triunfo Joint Powers Authority (JPA) was established between LVMWD and Triunfo to treat wastewater within the Malibu Creek watershed. The JPA owns and operates the Tapia Water Reclamation Facility (Tapia WRF), which currently treats approximately 7 million gallons per day (mgd) of wastewater. The JPA is the lead agency for the proposed Summer Flow Augmentation of Malibu Creek project (proposed project) under the California Environmental Quality Act (CEQA). The JPA has prepared this Initial Study (IS) and proposed Mitigated Negative Declaration (MND) to address the impacts of construction and operation of conveyance of potable water to Tapia WRF, and facilities for ammonia removal at Tapia WRF prior to discharge to Malibu Creek for augmentation of summer stream flows. The IS has been prepared in accordance with CEQA, Public Resources Code Section 21000 et seq., and the State CEQA Guidelines, Title 14 California Code of Regulations (CCR) Section 15000 et seq. The IS serves to identify the site-specific environmental impacts, evaluate their potential significance, and determine the appropriate document needed to comply with CEQA. As described in this IS, with mitigation incorporated into the proposed project, the augmentation of summer flows in Malibu Creek would not have a significant impact on the environment. Based on the information reviewed and contained herein, a MND is the appropriate CEQA document. Summer Flow Augmentation of Malibu Creek Page 1-1 Initial Study January 2019 Section 1 – Project and Agency Information 1.2.1 Project Background Wastewater treated at the Tapia WRF is either reused