The Special Environmental Studies (ES) Overlay District is intended to protect areas of high biological value and to protect the health, safety, and welfare of residents of the City by establishing regulations for addressing geologic hazards. The specific purposes of the ES Overlay District are to:
A. 
Require assessments of biological resources with development proposals in areas with sensitive habitats.
B. 
Mitigate impacts to wetland habitat or special status species through project development.
C. 
Require soils and geologic review of development proposals to assess potential seismic hazards related to slope stability, earthquake ground shaking, fault ground rupture, and liquefaction potential.
D. 
Require all geologic hazards be adequately addressed and mitigated through project development.
(Ord. 1432 § 2, 2010)
The provisions of this chapter shall apply to all areas of the City that the General Plan identified as ecologically sensitive habitat or susceptible to geologic hazards as well as other areas designated by State and federal agencies including Habitat Conservation areas, wetlands, and other areas identified on maps maintained by the City. In addition to the areas identified in the General Plan (Figure 7-2: Special Environmental Studies Required for Development Proposals), the City Engineer or Chief Planner may require biological assessments or geotechnical and engineering geology reports and apply other requirements in this chapter to properties outside the ES Overlay District based on maps and other studies, which document the existence of potential geologic hazards or sensitive habitats that warrant evaluation.
(Ord. 1432 § 2, 2010)
All development proposals in areas of the ES Overlay District that have been identified as ecologically sensitive habitat as shown on a map or maps maintained by the City require a site-specific assessment of biological resources in compliance with the following standards.
A. 
Site Design. Sensitive habitat areas shall be protected in the following order: (1) avoidance; (2) onsite mitigation; (3) offsite mitigation; and (4) purchase of mitigation credits.
B. 
Biological Report. A development application for a project on a site located within an area identified as ecologically sensitive habitat shall also include a report by a biologist or other qualified professional that contains the following:
1. 
An evaluation of the impact the development may have on the habitat, and whether the development will be consistent with the biological continuance of the habitat. Maximum feasible mitigation measures to protect the resource shall be identified and a program for monitoring and evaluating the effectiveness of the mitigation measures shall be included.
2. 
Conditions of approval recommendations for the restoration of damaged habitats, where feasible, including recommendations for the removal and prevention of re-establishment of invasive species.
C. 
Required Findings. Approval of a development permit for a project on a site located within an area identified as ecologically sensitive habitat shall not occur unless the applicable review body first finds that:
1. 
There will be no significant negative impact on the identified sensitive habitat and the proposed use will be consistent with the biological continuance of the habitat.
2. 
The proposed use will not significantly disrupt the habitat.
3. 
Adequate mitigation measures are required to mitigate impacts to significant biological resources.
4. 
There has been “no net loss” of wetlands. Disturbed wetlands have been replaced with the same type of wetlands.
5. 
Where feasible, damaged habitats will be restored as a condition of development approval.
(Ord. 1432 § 2, 2010)
All permit applications for projects located within areas of the ES Overlay District that have been identified as susceptible to geologic hazards as shown on a map or maps maintained by the City require the preparation of site-specific soils and geologic reports as follows:
A. 
Soil Report. A soil report, based upon adequate test borings or excavations, shall be prepared by a civil engineer licensed with the State of California, subject to the following requirements.
1. 
Contents. The soil report shall address potential problems of landsliding, ground shaking, and surface faulting. If the soil report indicates the presence of soil conditions which, if not corrected, could lead to structural defects, the report shall recommend corrective action that is likely to prevent structural damage to each structure proposed to be constructed.
2. 
Review of Report. The soil report shall be approved by the City Engineer if it is determined that the recommended action, where soil problems exist, is likely to prevent structural damage to each structure to be constructed. In order to make his or her determination, the City Engineer may have the soil report independently reviewed by a licensed geotechnical engineer, registered by the State of California, the cost of which shall be borne by the applicant. The recommended action shall be incorporated in the construction of each structure as a condition to the issuance of any building permit.
3. 
Exemption. A soil report shall not be required for:
a. 
Small Structures. Detached non-habitable structures that total 400 square feet in floor area or less.
b. 
Additions. A soils report may not be required for small additions (less than 50 square feet in floor area), based upon the determination of the City Engineer.
B. 
Geologic Report. A geologic report shall be prepared by a certified engineering geologist, subject to the following requirements:
1. 
Content. The report shall identify, describe and illustrate, where applicable, potential hazards of surface fault rupture, seismic shaking, liquefaction or landslide and shall include:
2. 
Review of Conditions. A review of the local and regional seismic and other geological conditions that significantly affect the proposed use.
3. 
Assessment. An assessment of conditions on or near the site that would contribute to the potential for damage of a proposed use from a seismic or other geological event, or the potential for a new use to create adverse effects upon existing uses because of identified geologic hazards. The conditions assessed are to include, where applicable, rainfall, soils, slopes, water table, bedrock geology, and any other substrate conditions that may affect seismic response, landslide risk or liquefaction potential.
4. 
Recommendations. Recommended building techniques, site preparation measures, or setbacks necessary to reduce risks to life and structural damage to property from seismic damage, landslide, groundwater and liquefaction to insignificant levels.
5. 
Exemption. A geologic report shall not be required for:
a. 
Individual Homes within Single Unit Subdivisions. Single-unit wood-frame or steel-frame dwellings to be built on parcels of land for which geologic reports have already been approved.
b. 
Small Structures. Detached non-habitable structures that total 400 square feet in floor area or less.
c. 
Additions. Additions to existing structures.
C. 
Waiver of Reports. No report is required for an application located in an area for which the City Engineer determines that sufficient information exists because of previous geology or soils reports.
(Ord. 1432 § 2, 2010)