Chapter 17.28
(FR) FAULT RUPTURE HAZARD OVERLAY DISTRICT
Sections:
17.28.030 Uses permitted subject to a conditional use permit.
17.28.050 Draft fault rupture hazard analysis.
17.28.060 Draft fault rupture hazard analysis – Geologic and soils investigations.
17.28.070 Draft fault rupture hazard analysis – Evaluation.
17.28.090 Final fault rupture hazard analysis.
17.28.110 Presence of significant geologic hazards.
17.28.010 Purpose.
The purpose of the Fault Rupture Hazard Overlay District is to protect life and property in the City of Lake Elsinore from hazards of geologic, faulting and set requirements for the evaluation of such areas prior to approval of any development permit or tentative map on the property. This Hazard Overlay District implements the policies of the Lake Elsinore General Plan and the provisions of the State of California Alquist-Priolo Special Studies Zones Act. The purpose of this overlay is to prohibit the location of most structures for human occupancy across traces of active faults and in landslide areas. [Ord. 772 § 17.07.010, 1986. Code 1987 § 17.07.010].
17.28.020 Application.
In any base district where the district symbol is followed by, as a part of such symbol, parenthetically enclosed letters “FR,” thus “(FR),” the additional requirements, limitations and standards contained in this section shall apply. The district symbol shall constitute the “base district” and the “FR” suffix shall constitute the “overlay district.” In the event of conflicting provisions of such a combined district, the requirements of the FR district shall take precedence over the requirements of the base district. Uses permitted by the FR district must, in each instance, be in compliance with those uses permitted by the applicable base district regulations and any other overlay district regulations. [Ord. 772 § 17.07.020, 1986. Code 1987 § 17.07.020].
17.28.030 Uses permitted subject to a conditional use permit.
A. All uses permitted in the base district, ordinarily subject to a conditional use permit are permitted which includes consideration and approval of a fault rupture hazard analysis in accordance with the procedures set forth in LEMC 17.28.040.
B. Conditions of approval shall include such recommended mitigation measures as are deemed appropriate to carry out the intent and purpose of this chapter. [Ord. 772 § 17.07.030, 1986. Code 1987 § 17.07.030].
17.28.040 Procedure.
No project application to which LEMC 17.28.030 applies shall be deemed complete and/or filed nor be accepted for filing until all fault rupture hazard analyses and documentation required hereunder, including any final analysis, is completed for presentation to the City. [Ord. 772 § 17.07.040, 1986. Code 1987 § 17.07.040].
17.28.050 Draft fault rupture hazard analysis.
A. Prior to the commencement of a proposed discretionary project which is located either wholly or partially within any area zoned (FR), requiring the approval of any development permit or tentative map, the proponent of the project shall prepare, or cause to be prepared, a draft fault rupture hazard analysis and submit the draft analysis to the Director of Community and Development Services. The Director of Community and Development Services, or his designee, shall determine the number of copies of the draft analysis required to be submitted. Before completing the draft fault rupture hazard analysis, the preparer shall consult directly with any person whom or organization which the preparer believes will be concerned with the geologic hazards in the project area and with other public agencies involved in carrying out or approving the project.
B. The draft fault rupture hazard analysis shall contain the following information, in form as approved by the Director of Community Development pertaining to the entirety of the proposed project:
1. The analysis shall be a combined in-depth geologic and soils investigation prepared by a registered geologist, certified by the State of California as an engineering geologist and by a licensed civil engineer qualified in soil mechanics. [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(A)(1), (2)(a)].
17.28.060 Draft fault rupture hazard analysis – Geologic and soils investigations.
Required geologic and soils investigations shall include the following:
A. Text.
1. Purpose and scope of investigation.
2. Geologic setting.
3. Site Description and Conditions. Include information on geologic units, graded and filled areas, vegetation, existing structures, etc., that may affect the choice of investigative methods and the interpretation of data.
4. Methods of Investigation.
a. Review of published and unpublished literature and records concerning geologic units, faults, groundwater barriers, etc.
b. Interpretation of aerial photographs and other remotely sensed images to detect fault-related topography, vegetation and soil contrasts, and other lineaments of possible fault origin.
c. Surface observations, including mapping of geologic units and structures, topographic features, springs, deformation of manmade structures, etc., both on and beyond the site.
d. Subsurface Investigations.
(1) Trenching and other extensive excavations to permit detailed and direct observation of continuously exposed geologic units and features which must be carefully logged.
(2) Borings and test pits to permit collect of data on geologic units and groundwater specific locations. Data points must be sufficient in number and adequately spaced to permit valid correlations an interpretations.
e. Geophysical Investigations.
(1) Seismic refraction.
(2) Magnetic intensity.
(3) Other (e.g., electrical resistivity, seismic reflection, gravity).
f. Other methods should be included when special conditions permit, or requirements for critical structures demand, a more intensive investigation.
(1) Aerial reconnaissance overflights.
(2) Geodetic and strain measurements, microseismicity monitoring, or other monitoring techniques.
(3) Radiometric analysis, stratigraphic correlation, soil profile development, paleomagnetism, or other age-dating techniques to identify the age of faulted or unfaulted units or surfaces.
5. Conclusions.
a. Location and existence (or absence) of hazardous faults on or adjacent to the site.
b. Type of faults and nature of anticipated offset: direction of relative displacement and maximum displacement that is possible.
c. Probability of or relative potential for future surface displacement. The likelihood of future ground rupture can seldom be stated mathematically, but may be stated in semi-quantitative terms such as low, moderate, or high.
d. Degree of confidence in and limitations of data and conclusions.
6. Recommendations.
a. Setback distances from hazardous faults, if appropriate. State and local law may dictate minimum standards.
b. Risk evaluations relative to the proposed development – professional opinions are acceptable.
B. References.
1. Literature and records cited and reviewed.
2. Aerial photographs or images interpreted – list type, scale, source, index numbers, etc.
3. Other sources of information including well records, personal communications, and other data sources.
C. Illustrations. These are essential to the understanding of the report and to reduce the length of text.
1. Location Map. Identify site locality, significant faults, geographic features, seismic epicenters, and other pertinent data; 1:24,000 scale is recommended.
2. Site Development Map. Show site boundaries, existing and proposed structure, graded areas, streets, exploratory trenches, borings, geophysical traverses, and other data; recommended scale is one inch equals 100 feet, or larger.
3. Geologic Map. Shows distribution of geologic units (if more than one), faults and other structures, geomorphic features, aerial photo lineaments, and springs; on topographic map 1:24,000 scale or larger; can be combined with III (A) or III (B).
4. Geologic cross-sections, if needed to provide three-dimensional picture.
5. Logs of Exploratory Trenches and Borings. Show details of observed features and conditions; should not be generalized or diagrammatic.
6. Geophysical data and geologic interpretations.
D. Statement of other public agencies having approval authority over the project.
E. Statement of other persons and organizations consulted concerning the geologic effects of the project.
F. Appendix including supporting data not included above (e.g., waterwall date).
G. Signature and registration number of the investigating geologist/civil engineer (preparer(s)). [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(A)(2)(b)].
17.28.070 Draft fault rupture hazard analysis – Evaluation.
Forthwith upon completion of the draft analysis, the Director of Community Development, or his designee, shall:
A. Cause an independent evaluation and analysis of the draft analysis to be conducted. Such independent evaluation and analysis may be referred by the Director, or his designee, to a registered geologist certified by the State of California as an engineering geologist and/or a licensed civil engineer qualified in soil mechanics retained by the City for purposes of conducting such independent evaluation and analysis;
B. Consult with and seek to obtain comments from any public agency which has jurisdiction by law with respect to the project; and
C. Consult with and seek to obtain comments from any person or organization identified in the draft analysis as being concerned with the geologic hazards in the project area. [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(B)].
17.28.080 Public hearing.
If the proponent of the project or the Director of Community Development, or his designee, determines that a public hearing would facilitate the purposes and goals set forth in this chapter, conduct such a hearing. If a hearing is to be conducted, all persons, organizations and public agencies identified in the draft analysis shall be notified of such hearing. [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(C)].
17.28.090 Final fault rupture hazard analysis.
A. Immediately subsequent to the completion of the activities set forth in LEMC 17.28.050(B) and 17.28.060, the Director of Community and Development Services, or his designee, shall prepare a final fault rupture hazard analysis with respect to the project in question.
B. The contents of the final fault rupture hazard analysis shall consist of the following:
1. The draft special geologic study zone analysis or a revision of the draft;
2. Comments and recommendations received with respect to the draft special geologic study zone analysis, either verbal or in summary form;
3. A list of persons, organizations and public agencies commenting on the draft special geologic study zone analysis;
4. The responses of the preparer and/or the City to significant geologic hazards identified in the review and consultation process;
5. Comments, recommendations, responses and other material may be attached to the draft special geologic study zone analysis and need not take the form of a complete revision of the entirety of said draft. The responses to significant geologic hazards identified shall describe the disposition of such issues (e.g., revisions to the proposed project to mitigate the anticipated geologic impact);
6. In the event that significant geologic hazards are identified or objections made, and mitigation or other measures to reduce the impact of such significant hazards are rejected, such rejections must be addressed in detail giving reasons why such specific measures were not accepted and factors of overriding importance warranting an override of the suggested mitigation measures.
C. The final fault rupture hazard analysis shall then be presented to that agency of the City which first must consider the project. Such presentation shall not occur until at least 30 days subsequent to the mailing of any notice specified in LEMC 17.28.040(C). Such agency of the City shall certify that the final fault rupture analysis, including any modifications, additions or deletions to the analysis presented to the agency which the agency deems appropriate, has been completed in compliance with this chapter and that it has reviewed and considered the information contained in the fault rupture hazard analysis. Such certification shall be by resolution or minute motion and shall occur prior to the rendering of any decision approving a project. Such certification, as well as any subsequent certification by the City Council, shall be completed within one year from the date the application for the project is accepted as complete. All time limits described herein may be extended once for a maximum of 90 days if compelling circumstances justify such extension, and the applicant agrees thereto. If the City Council makes the final decision on a project subsequent to consideration thereof by another City agency, e.g., the Planning Commission, the City Council shall certify as stated above in this LEMC 17.28.040(C). [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(D), (E)].
17.28.100 Notice.
In the event that (1) a City agency is required to give notice of public hearing which is to be conducted prior to that agency considering the project in question, and (2) the fault rupture hazard analysis process is applicable to said project, said notice shall include the notice specified in LEMC 17.28.040(C) and the hearing in question shall include a hearing on the subject of the fault rupture hazard analysis. [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(F)].
17.28.110 Presence of significant geologic hazards.
When a special geologic study zone analysis identifies one or more significant geologic hazards in the project area, the project may be approved only by a written resolution which finds that:
A. Changes or alterations have been required in, or incorporated into, the project which mitigate or avoid the significant geologic hazards identified in the final analysis; and/or
B. Such changes or alterations are within the responsibility or jurisdiction of another public agency and such changes have been or can and should be adopted by that agency; and/or
C. Specific economic, social, or other considerations make infeasible the mitigation measures or project alternatives identified in the final analysis. [Ord. 772 § 17.07.050, 1986. Code 1987 § 17.07.050(G)].
17.28.120 Fees.
The proponent of any project for which a fault rupture hazard analysis is to be prepared shall be required to pay a fee to defray the City’s cost of evaluating and analyzing any draft fault rupture hazard analysis and the preparation of any final special fault rupture hazard analysis. The fees required to defray the City’s costs shall be established by a resolution of the City Council. [Ord. 772 § 17.07.060, 1986. Code 1987 § 17.07.060].