Valley Center Storage Project Conceptual Revegetation Plan San Diego County, California Project Number: PDS-2020-STP-20-011 Prepared for the County of San Diego Developer: VALLEY CENTER ESS, LLC 11455 El Camino Real, Suite 160 San Diego, CA 92130 Prepared by: CHAMBERS GROUP, INC. 9620 Chesapeake Drive, Suite 202 San Diego, CA 92123 Principal Author: Heather Clayton, Senior Botanist June 24, 2020 Valley Center Storage Project Conceptual Revegetation Plan Valley Center, San Diego County, CA TABLE OF CONTENTS Page SECTION 1.0 – INTRODUCTION ........................................................................................................... 1 1.1 PURPOSE OF THE CONCEPTUAL REVEGETATION PLAN ................................................................ 1 1.2 RESPONSIBLE PARTIES .................................................................................................................. 1 1.3 LOCATION OF THE DEVELOPMENT PROJECT ................................................................................ 1 1.4 SUMMARY OF OVERALL DEVELOPMENT PROJECT ....................................................................... 2 1.4.1 Current Environmental Setting and Site Conditions ........................................................ 4 1.4.2 Impacts to Special Status Plant Species ........................................................................... 5 1.4.3 Impacts to Special Status Wildlife .................................................................................... 5 1.4.4 Impacts to Migratory Birds .............................................................................................. 6 SECTION 2.0 – COMPENSATORY MITIGATION GOALS .......................................................................... 7 2.1 RESPONSIBILITIES.......................................................................................................................... 7 2.2 COMPENSATORY MITIGATION ..................................................................................................... 8 2.2.1 Cumulative Impact Analysis ............................................................................................. 9 2.3 TIME LAPSE ................................................................................................................................. 10 2.4 COST ............................................................................................................................................ 10 SECTION 3.0 – COMPENSATORY MITIGATION SITE DESCRIPTION ....................................................... 12 3.1 SITE SELECTION ........................................................................................................................... 12 3.2 LOCATION AND SIZE OF SITE ...................................................................................................... 12 3.3 JURISDICTIONAL WETLANDS AND WATERWAYS ........................................................................ 12 3.4 TYPES, FUNCTIONS AND VALUES OF HABITATS TO BE IMPACTED ............................................. 12 3.4.1 Permanent Impacts ........................................................................................................ 13 3.4.2 Temporary Impacts ........................................................................................................ 13 3.4.3 Disturbed Habitat ........................................................................................................... 15 3.4.4 Non-Native Grassland .................................................................................................... 15 3.4.5 Diegan Coastal Sage Scrub: Inland Form........................................................................ 15 3.4.6 Bare Ground ................................................................................................................... 16 3.4.7 Rock ................................................................................................................................ 16 3.4.8 Urban/Developed .......................................................................................................... 16 3.4.9 Extensive Agriculture – Row Crops ................................................................................ 16 3.5 REFERENCE SITES ........................................................................................................................ 17 3.5.1 Reference Site 1 ............................................................................................................. 17 3.5.2 Reference Site 2 ............................................................................................................. 17 SECTION 4.0 – IMPLEMENTATION PLAN ............................................................................................ 18 4.1.1 Rationale for Expecting Implementation Success .......................................................... 18 4.1.2 Financial Assurances ...................................................................................................... 18 4.1.3 Schedule ......................................................................................................................... 18 Chambers Group, Inc. ii 21206 Valley Center Storage Project Conceptual Revegetation Plan Valley Center, San Diego County, CA 4.1.4 Site Preparation ............................................................................................................. 18 4.1.5 Planting Plan .................................................................................................................. 19 4.1.6 Season of Planting .......................................................................................................... 22 4.1.7 Irrigation ......................................................................................................................... 22 SECTION 5.0 – COMPENSATORY MITIGATION SITE MAINTENANCE DURING MONITORING ................. 23 5.1 MAINTENANCE ACTIVITIES ......................................................................................................... 23 5.1.1 Proposed Weeding Program .......................................................................................... 23 5.1.2 Proposed Pruning Program ............................................................................................ 23 5.1.3 Proposed Trash Removal Program................................................................................. 23 5.1.4 Proposed Pest Control Program .................................................................................... 24 SECTION 6.0 – COMPENSATORY MITIGATION SITE MONITORING PLAN ............................................. 25 6.1 PERFORMANCE STANDARDS ...................................................................................................... 25 6.1.1 Success Criteria .............................................................................................................. 25 6.1.2 Adaptive Management and Remedial Actions .............................................................. 26 6.1.3 Target Functions and Values .......................................................................................... 26 6.1.4 Target Acreage ............................................................................................................... 27 6.2 MONITORING REQUIREMENTS ................................................................................................... 27 6.2.1 Monitoring Methods ...................................................................................................... 27 6.2.2 Monitoring Schedule ...................................................................................................... 28 6.2.3 Monitoring Reports ........................................................................................................ 28 SECTION 7.0 – COMPLETION OF COMPENSATORY MITIGATION ......................................................... 30 SECTION 8.0 – CONTINGENCY MEASURES FOR COMPENSATORY MITIGATION ................................... 31 8.1 INITIATING CONTINGENCY PROCEDURES ................................................................................... 31 8.2 ALTERNATIVE LOCATIONS FOR CONTINGENCY COMPENSATORY MITIGATION ........................ 31 8.3 FUNDING ..................................................................................................................................... 31 SECTION 9.0 – REFERENCES .............................................................................................................. 32 Chambers Group, Inc. iii 21206 Valley Center Storage Project Conceptual Revegetation Plan Valley Center, San Diego County, CA LIST OF TABLES Page Table 1: Direct Impacts by Vegetation Type ................................................................................................. 4 Table 2: Responsible Parties ......................................................................................................................... 7 Table 3: Estimates of Project Disturbance to Vegetation Communities within each Gen-tie Alignment Option ........................................................................................................................................................... 8 Table 4: Estimated Cost Summary for Revegetation/Restoration Activities .............................................. 11 Table 4: Seed Mix .......................................................................................................................................