The geologic hazard (GH) overlay district is created to provide greater public safety by establishing review procedures and setbacks for areas that are subject to potential geologic problems such as ground shaking, earthquake faults, liquefaction, and landsliding.

(Ord. 68 § 9.51.010, 1995)

A.

The geologic hazard overlay district shall apply to the Chino Hills fault hazard zone, as delineated in the General Plan safety element.

B.

The geologic hazard overlay district standards and requirements shall also be applied to areas where landslides, liquefaction hazards, and other geologic hazards are known or suspected to occur, as identified in the General Plan safety element.

(Ord. 68 § 9.51.020, 1995)

A.

A detailed geologic study prepared by a registered geologist shall be submitted with all land use applications and development permits proposed within the geologic hazard overlay district. The Building Official shall determine the scope of the study, depending upon the geologic hazards affecting the subject property.

B.

Exemptions to the requirement for a geologic study consist of:

1.

Single-family wood frame dwellings located within a division of land for which an approved geologic report was prepared. However, for dwellings proposed to be located in hillside areas on slopes greater than fifteen (15) percent or where known geologic hazards exist, this exemption shall not apply;

2.

Uses accessory to a residence;

3.

The alterations or additions to any structure where the value or area does not exceed fifty (50) percent of the existing structure.

(Ord. 68 § 9.51.030, 1995)

When a development project is proposed within a geologic hazard overlay district, the following standards shall apply:

A.

All structures used for human occupancy, other than single-family woodframe structures, shall be set back from any fault, including the Chino Hills fault, as indicated in site-specific geotechnical reports.

B.

Structures used for critical facilities shall not be located within any fault zone. Critical facilities shall include dams, reservoirs, fuel storage facilities, police and fire stations, schools, hospitals, and high-occupancy facilities.

C.

Utility lines and streets shall not be placed within the construction setback area of a hazardous fault except for a crossing which can be made perpendicular to the fault trace or as recommended by the project geologist and approved by the reviewing authority.

D.

The following conditions apply to areas subject to landslide hazards:

1.

All facilities and streets should be sited in a manner which minimizes erosion potential.

2.

Natural vegetation shall be retained and protected where possible. Where inadequate vegetation exists, additional landscaping shall be provided. Any additional landscaping shall be compatible with the local environment and capable of surviving with a minimum of maintenance and supplemental water.

3.

The development should be designed to minimize water run-off. Provisions should be made to effectively accommodate any increased run-off.

4.

Measures shall be taken to offset the possible affects of landslides. A detailed geologic report identifying these measures shall be required prior to the issuance of building permits.

5.

All proposed facilities located within landslide hazard areas shall be constructed in a manner to minimize or eliminate subsidence damage.

(Ord. 68 § 9.51.040, 1995)