Little Deer Creek Restoration and Flood Mitigation Project CEQA Initial Study / Mitigated Negative Declaration Prepared for: City of Nevada City Prepared by: Stantec Consulting Services Inc.& Sierra Streams Institute November 7, 2016 LITTLE DEER CREEK RESTORATION AND FLOOD MITIGATION PROJECT Table of Contents 1.0 PROJECT DESCRIPTION ...............................................................................................1.1 1.1 BACKGROUND ............................................................................................................... 1.1 1.2 PROJECT LOCATION ...................................................................................................... 1.2 1.3 PURPOSE AND NEED ...................................................................................................... 1.5 1.4 PROPOSED IMPROVEMENTS ......................................................................................... 1.5 1.4.1 Stream Improvements ................................................................................. 1.6 1.4.2 Field Improvements ..................................................................................... 1.6 1.4.3 Trail Improvements ...................................................................................... 1.6 1.5 PROJECT PHASING ......................................................................................................... 1.7 1.6 PROJECT CONSTRUCTION ............................................................................................ 1.7 1.6.1 Stream Construction ................................................................................... 1.8 1.6.2 Field Construction ........................................................................................ 1.9 1.6.3 Trail Construction ....................................................................................... 1.10 1.6.4 Access, Mobilization and Staging ........................................................... 1.11 1.6.5 Project Schedule ....................................................................................... 1.12 1.7 CEQA PROCESS ........................................................................................................... 1.13 1.8 SCOPE OF THIS STUDY .................................................................................................. 1.13 2.0 ENVIRONMENTAL CHECKLIST FORM AND ANALYSIS ...............................................2.14 3.0 ENVIRONMENTAL IMPACTS ......................................................................................3.16 3.1 AESTHETICS .................................................................................................................... 3.16 3.1.1 Regulatory Setting ..................................................................................... 3.16 3.1.2 Environmental Setting ............................................................................... 3.17 3.1.3 Impact Analysis .......................................................................................... 3.18 3.2 AGRICULTURAL RESOURCES ....................................................................................... 3.20 3.2.1 Regulatory Setting ..................................................................................... 3.20 3.2.2 Environmental Setting ............................................................................... 3.21 3.2.3 Impact Analysis .......................................................................................... 3.22 3.3 AIR QUALITY .................................................................................................................. 3.24 3.3.1 Regulatory Setting ..................................................................................... 3.24 3.3.2 Environmental Setting ............................................................................... 3.27 3.3.3 Impact Analysis .......................................................................................... 3.28 3.3.4 Mitigation .................................................................................................... 3.35 3.4 BIOLOGICAL RESOURCES ........................................................................................... 3.38 3.4.1 Regulatory Setting ..................................................................................... 3.38 3.4.2 Environmental Setting ............................................................................... 3.44 3.4.3 Impact Analysis .......................................................................................... 3.83 3.4.4 Mitigation .................................................................................................... 3.90 3.5 CULTURAL RESOURCES ................................................................................................ 3.93 3.5.1 Regulatory Setting ..................................................................................... 3.93 3.5.2 Environmental Setting ............................................................................... 3.99 3.5.3 Impact Analysis ........................................................................................ 3.108 LITTLE DEER CREEK RESTORATION AND FLOOD MITIGATION PROJECT 3.5.4 Mitigation .................................................................................................. 3.112 3.6 GEOLOGY AND SOILS ............................................................................................... 3.115 3.6.1 Regulatory Setting ................................................................................... 3.115 3.6.2 Environmental Setting ............................................................................. 3.116 3.6.3 Impact Analysis ........................................................................................ 3.119 3.6.4 Mitigation .................................................................................................. 3.122 3.8 HAZARDS AND HAZARDOUS MATERIALS ................................................................. 3.131 3.8.1 Regulatory Setting ................................................................................... 3.131 3.8.2 Environmental Setting ............................................................................. 3.133 3.8.3 Impact Analysis ........................................................................................ 3.134 3.8.4 Mitigation .................................................................................................. 3.139 3.9 HYDROLOGY AND WATER QUALITY ......................................................................... 3.142 3.9.1 Regulatory Setting ................................................................................... 3.142 3.9.2 Environmental Setting ............................................................................. 3.145 3.9.3 Impact Analysis ........................................................................................ 3.148 3.9.4 Mitigation .................................................................................................. 3.155 3.10 LAND USE PLANNING ................................................................................................. 3.159 3.10.1 Regulatory Settings .................................................................................. 3.159 3.10.2 Environmental Setting ............................................................................. 3.161 3.10.3 Impact Analysis ........................................................................................ 3.162 3.11 MINERAL RESOURCES ................................................................................................ 3.164 3.11.1 Regulatory Setting ................................................................................... 3.164 3.11.2 Environmental Setting ............................................................................. 3.164 3.11.3 Impact Analysis ........................................................................................ 3.165 3.12 NOISE ........................................................................................................................... 3.166 3.12.1 Regulatory Setting ................................................................................... 3.170 3.12.2 Environmental Setting ............................................................................. 3.172 3.12.3 Impact Analysis ........................................................................................ 3.173 3.12.4 Mitigation .................................................................................................. 3.178 3.13 POPULATION AND HOUSING .................................................................................... 3.180 3.13.1 Regulatory Setting ................................................................................... 3.180 3.13.2 Environmental Setting ............................................................................. 3.181 3.13.3 Impact Analysis ........................................................................................ 3.181 3.14 PUBLIC SERVICES ........................................................................................................ 3.183 3.14.1 Regulatory Setting ................................................................................... 3.183 3.14.2 Environmental Setting ............................................................................. 3.183 3.14.3 Impact Analysis 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