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HomeMy WebLinkAbout18-Public Works - File Nort.50 ~/'V CITY OF SAN BERNQDINO - REQUEST FWI COUNCIL Jd:TION From: ROGER G. HARDGRAVE REC'D.-AOM~~l:. Adoption of Procedures and Guidelines -- Liquefaction Dept: Public Works/Engineering IS8S Jljl \ 8 Ar.\ Ii): 05 Investigations and Reports Date: 7-14-89 Synopsis of Previous Council action: 08-16-82 -- Resolution No. 82-345 adopted to establish procedure" and guidelines for evaluating the hazard of liquefac- tion of soils. 03-23-89 -- Legislative Review Committee reviewed proposed pro- cedures and guidelines for evaluating liquefaction potential. Concern was expressed over reference to Water Department maps. Item continued. 07-17-89' -- First reading of Ordinance creating Section 15.08 of San Bernardino Municipal Code Liquefaction Potential, conducted. Recommended motion: Adopt resolution. cc: Marshall Julian Jim Richardson Jim Penman e-Brad Kilger Herb Wessel Larry Reed Contact person: Gene R. Klatt Staff Report & Supporting data attached: Resolution Phone: ')125 Ward: All FUNDING REQUIREMENTS: Amount: N / A Source: (Acct. No.) (Acct, Descriotion) Finance: Council Notes: ...<:: n....:" AClenda Item No.. 1a' "CITY OF SAN BERNCRDINO - REQUEST .oR COUNCIL ACTION STAFF REPORT Concurrently, with the second reading of the Ordinance on Liquefaction, adoption of the attached resolution will set forth the guidelines for the preparation of the required reports and the contents of the reports. In meetings with Planning, Building and Safety, Water Department, City Attorney's Office, Consulting Soils Engineers and others, it was determined that a guideline for the preparation of reports would be useful and necessary to insure adequate compliance with the adopted ordinance. After much discussion and consideration, agreement was reached on the content, format and submittal process for such reports. The attached resolution sets forth these requirements. Staff recommends the adoption of the attached resolution adopting procedures and guidelines for liquefaction reports. 7-14-89 75.0264 o o 1 RESOLUTION NO. 2 RESOLUTION OF THE CITY OF SAN BERNARDINO ADOPTING 3 PROCEDURES AND GUIDELINES FOR LIQUEFACTION INVESTIGATIONS AND REPORTS REQUIRED BY CHAPTER 15.08 OF THE SAN BERNARDINO MUNICIPAL 4 CODE; ,AND RESCINDING RESOLUTION NO. 82-345. 5 BE IT RESOLVED BY THE MAYOR AND COMMON COUNCIL OF THE CITY OF SAN BERNARDINO AS FOLLOWS: 6 SECTION 1. Administrative procedures/Guidelines for 7 Liquefaction Investigations and Reports. 8 In accordance with Chapter 15.08 of San Bernardino 9 The Director of Public Works/City Engineer has 10 established the following procedures/guidelines for liquefaction Municipal Code. 11 investigations and reports. 12 13 14 SECTION 2. The Investigation. A. Purpose. The investigation shall be designed and carried out to determine the potential for liquefaction. For 15 complex, essential structures, the investigation shall be as 16 thorough as current technology will permit. Investigations may 17 also require the expertise of a registered geologist, or 18 registered engineering geologist, since both geologic/seismic 19 elements and quantitative materials testing will be involved. 20 Site investigation. B. 21 Seismic factors. The history of earthquake 1. 22 activity and recurrence intervals of damaging earthquakes 23 shall be discussed. A design earthquake shall be 24 postulated, with a best estimate of the following 25 characteristics as they will be experienced at the site: 26 Richter magnitude. Maximum Probable RoOk Accel~ration from a. 27 b. 28 PZ/dys July 10, 1989 1 10 11 1 2 3 4 5 6 7 8 9 o o various faults, (as shown in the Seismic Element of the General Plan) that produces the highest value. c. Time (duration) of strong shaking. d. Dominant frequencies of seismic spectra. e. In no case shall the rock acceleration be less than the amount indicated on the map in the Seismic Element of the General Plan entitled: 'Maximum Credible Rock Acceleration from Earthquakes. ' 2. Hydrologic conditions. The historical record of 12 depths to the ground water table (or saturated conditions) shall 13 be determined for the site from City records. The depth to 14 ground water used in the analysis, as determined by borings, 15 shall be stated, but design will be based on a level no less than 16 ten (10) feet. 17 18 3. Subsurface Investigation. Borings shall be used to determine the necessary subsurface information. They should 19 extend to a minimum depth of fifty (50) feet and be spaced across 21 20 the site so that significant variations in subsurface,conditions 23 22 be: ,will be defined. 24 25 26 27 28 a. b. Examples of significant subsurface data would drilling rate, standard penetration test at every five (5) feet from surface ASTM No. D 1586-67, c. d. PZ;dys July 10, 1989 classification, definition, and depth of soils, general stratigraphy. 2 10 o o 1 For essential projects, more subsurface information 2 utilizing pits, trenches and geophysical investigations may be 3 necessary. They allow direct observation of the undisturbed 4 vertical section so that evidence of liquefaction such as sand 5 boils, sand dikes, or chaotic disturbance of the soil or sediment 6 can be viewed. Also, horizontal and vertical permeability can be 7 better estimated from a view of the undisturbed layering. 8 Furthermore, the ancient sedimentary environment of the site can 9 . be interpreted from the trench of pit walls. 4. Geophysical Investigation. Refraction seismic 11 techniques may be useful to define the ground water table, but 12 this indirect method should only be used to confirm or extend 13 downhole or trench data. 14 15 The report may be simple or comprehensive, depending upon SECTION 3. The Report. 16 the vulnerability of the site to liquefaction and the kinds of 17 buildings or other structures to be built. The following topics 18 should be considered and included if pertinent. 19 20 21 22 23 24 25 26 27 28 A. Text 1. Site location relative to established property boundaries. 2. City reference number (CUP, ROP, Tract No., ,etc.) 3. 4. Purpose and scope of investigation. Design earthquake parameters (discussed above). 5. Description of kind and location of proposed construction. 6. Procedures and techniques used in the PZ/dys July 10. 1989 3 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 o o 1 investigation. Detailed description of subsurface conditions and 2 7. 3 results of quantitative testing. 4 B. Conclusions and Recommendations. 5 1. Identify the location and distribution of areas 6 vulnerable to liquefaction and estimate the depth of 7 zones of possible failure due to liquefaction. 8 2. Identify critical parameters of the design 9 earthquake: fault, magnitude, accelerations, duration, frequency, etc. 3. Identify procedures for reducing hazard of liquefaction. a. geotechnical. b. structural. C. Documentation of Report. 1. 2. PZ/dys July 10, 1989 Include index map showing location of s~te. Include site plan which shall display: a. topography (if available); b. proposed building location; c. locations of borings, wells, trenches; d. surface geological features. 3. Include logs of borings (with blow counts), wells trenches. 4. Include sample descriptions and locations. 5. Include sample analysis and tests, based upon the penetration analysis developed by Dr. Bolton Seed, or other approved method. 4 10 11 12 o o 1 6. Include graphs and charts, as needed to 2 demonstrate liquefaction potential. 3 4 7. Include description of analytical. techniques used. 5 8. Include signatures and license numbers of 6 Registered Civil Engineers responsible for the report, and any Registered Geologists that assisted in the 7 8 preparation. 9 9. Include a list of references utilized in report. 10. List final recommendations with references to conclusions. SECTION 4. Submittal. 13 Two copies of the required Liquefaction Report and 14 Mitigation Measures shall be submitted to the Director of Public 16 15 Works/City Engineer and approved prior to issuance of grading and building permits. If the Liquefaction Report and Mitigation 17 Measures are approved by the Director of Publiq Works/City 18 Engineer, a copy will be forwarded to the Director of Building 19 20 structural plans shall contain a statement that the building has and Safety for reference in checking structural plans. The 21 been designed in accordance with the Mitigation Measures 23 22 contained in the Liquefaction Report. If the Liquefaction Report and M~tigation Measures 24 submitted to the Director of Public Works/City Engineer are 25 determined to be unacceptable,' the interested party may, appeal 26 this decision to the Mayor and Council. No permits will be 27 issued prior to approval by the Director of Public Works/City 28 PZ/dys July 10, 1989 5 o o 1 Engineer or prior to an appeals decision by the Mayor and Common 2 Council approving the Liquefaction Report and Mitigation 3 Measures. 4 I HEREBY CERTIFY that the foregoing resolution was duly 5 adopted by the Mayor and Common Council of the City of San 6 Bernardino at a meeting thereof, held on the 7 day of , 1989, by the following vote, to wit: 8 AYES: Council Members 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 9 of NAYS: ABSENT: City Clerk The foregoing resolution is hereby approved this day , 1989. W. R. Holcomb, Mayor Approved as to form and legal content: JAMES F. PENMAN, City Attorney I' Ii 1~ BYU0><.h ' '~"-".... PZ/dys July 10, 1989 6 , o o "TV ~~ S~N \\E'\N~,RiJ\Nt ~," I 'WI _,.."vi' .,. :-.,,"'j t~ '~l.r' ~ '. Hh:it..........,. . :r:' .~~~~:',., ."'''EE' ..,. , ," : .'I.~!..1\i'" .~" . -,i " NOTICE OF PREPARATION OF NEGATIVE DECLARATION 15 ~\ S O~ OF ENVIRONMENTAL IMPACT 89 ~UG , THE CITY OF SAN BERNARDINO proposes to adopt a Negative Declaration for the following projects. The Environmental Review Committee found that the project will not have a significant effect on the environment on the basis of the Initial Study and mitigation measures (If applicable). L CONDITIONAL USE PERMIT NO. 89-31 - Tenant improvements to an existing office building to include classrooms and an admi- nistration office for use as a night school located at 685 East Carnegie Drive. 3. REVIEW OF PLANS NO. 89-39 - To develop 16 single-family homes on 16 existing substandard lots located on Acacia Street between 28th and 29th Streets. v-:. PROPOSED LIQUEFACTION RESOLUTION - The City is proposing a reso- lution to replace the existing resolution which regulates the format and contents of any required liquefaction study. Copies of the Initial Study are available for public review at the Planning Department, 300 North "D" Street, San Bernardino, CA 92418, and the Feldheym Library, 555 West 6th Street, San Bernardino, CA. Any environmental comments you have should be received in this office no later than 4:00 p.m., August 30, 1989. If you do not respond in writing, we will assume that you have no opinions and/or recommendations on the above projects. SUBMITTED: August, 15, 1989 PUBLISH: August 17, 1989 CITY OF SAN BERNARDINO PLANNING DEPARTMENT 300 North "D" Street San Bernardino, CA 92418 384-5057 CP C5 NOPND81089 C Y OF SA'N BERNA INO INITIAL STUDY Liquefaction Resolution A Resolution of the City Council of San Bernardino to regulate the preparation of Liquefaction Reports for projects located in areas of the City of San Bernar- dino which have been identified in the City's General Plan as having a high or moderately high to moderate , potential for Liquefaction in a major earthquake. August 4, 1989 . Prepared for: Department of Public Works/City Engineer Prepared by: MICHAEL W. GRUBBS Public Works/Engineering City of San Bernardino C Y OF SAN BERNA INO DEPARTMENT OF PUBLIC WORKS/CITY ENGINEER INITIAL STUDY Liquefaction is the phenomenon of soil behaving as a liquid during a major earthquake. Studies have shown that liquefaction is most likely to occur during hiah groundwater conditions in non-cohesive soils (medium sands silts). Duringa liquefaction event, soils lose a portion or all of their ability to support loads sometimes resulting in upset and/or failure of building founda- tions in the liquefaction area. The General Plan has attempted to identify areas of the City which have a high (H) or moderately high to moderate (MHM) potential for liquefaction in the event of a major earthquake. Since 1982, regulation of development within moderate and high liquefaction potential areas has been carried out under Resolution No. 82-345, which requires that s liquefaction report be prepared for all new developments in the City determined high to moderate zones (Zones A & 8) except single family wood frame detached, two unit wood frame single story and additions up to 25% of the original. Resolution No. 82-345 was written after the 1978-80 floods and was based on limited experience. In working with it over the years we have found the requirements of the liquefaction to be ambiguous and sometimes inadequate. An Ordinance enabling regulation of development in the liquefac- tion zones is currently under consideration by the City Council and has been recommended for a negative declaration by the Environmental Review Committee. This Resolution will satisfy Section 15.08.070 of the proposed ordinance by defining the requirements of liquefaction reports. ' > - - CITY OF SAN BERNARDINO ENVIRONMENTAL IMPACT CHECKLIST ""'IIil BACKGROYND Application Number: Project Description: Resolution to regulate the preparation of lique- faction r~rts for develqpments within areas of the City which have been identi- ~;Qd ~c:!.h~u;ng high n:r mrvlo,...a't'oly high ton 1'TlfViQ,..~-t-Q pr"nJ:llhility nF li1.11,::r.fJ:llrtinn ~n a major earthquake. Location: Al11J:llnrt tJit'hin t'ho J:lll""QJ:ll nf th,:lo r:it-y itiQnt-ifi.on in t-ho r~nQrJ:lll PlAn as having a high or moderately high to moderate potential of liquefaction in a major earthquake. Environmental Constraints Areas: None General Plan Designation: Various Zoning Designation: Various B. ~HVIEONM~NTAL IMPACTS Explain answers, where appropriate, on a separate attached sheet. 1. EaJ.th Resources Will the proposal result in: Yes No Maybe a. Earth filII more? movement (cut and/or of 10,000 cubic yards or x b. Development and/or a slope greater natural grade? ' grading than on 15% x c. Development Alquist-Priolo Zone? within the Special Studies x d. Modification of any unique geologic or physical feature? x \.. REVISED 12/87 ~ PAGE 1 OF 8 - 4. - r n t"'"\ Yes No Maybe ..... e. Soil erosion on or off the project site? f. Modification of a channel, creek or river? x x g. Development subject mudslides, other similar within an area to landslides, liquefaction or hazards? x h. Other? 2. bIR RESOURCES: Will the proposal result in: Substantial an effect quality? b. The creation of objectionable odors? a. air upon emissions or ambient air x x c. Development within a high wind hazard area? x 3. WATER RESOURCES: proposal result in: a. Changes in absorption rates, drainage patterns, or the rate and amount of surface runoff due to impermeable surfaces? Will the y b. Changes in the course or flow of flood waters? y c. Discharge into surface waters or any alteration of surface water quality? d. Change in the quantity or quality of ground waters? e. . Exposure of people or property to flood hazards? f. Other? x , x x ~ ~ REVISED 12/87 PAGE 2 OF 8 n ("'\ Maybe " ,. 4. BIOLOGICAL R~SOURC~~: proposal result in: Could the a. Change unique, species habitat trees? in the number of any rare or endangered of plants or their including stands of b. in the number of any rare or endangered of animals or their Change unique, species habitat? c. Other? 5. NOISE: Could the proposal result in: a. Increases in existing noise levels? b. Exposure of people to exterior noise levels over 65 dB or interior noise levels over 45 dB? c. Other? 6. Will the LAND_ USE: result in: proposal a. A change in the land use as designated on the General Plan? b. Development within an Airport District? c. Development within wGreenbeltW Zone A,B, or C? d~ Development within a high fire hazard zone? e. Other? Yes No x x x x x x x x x ~ ~ REVISED 10/87 PAGE 3 OF 8 " r - Maybe '" 7. MAN-MADE HA~~~~: project: Will the a. Use, store, transport or dispose of hazardous or toxic materials (including but not limited to oil, pesticides, chemicals or radiation)? b. Involve the release hazardous substances? of c. Expose people to the potential health/safety hazards? d. Other? 8. HOUSING: Will the proposal: a. Remove existing housing or create a demand for additional housing? b. Other? 9. ~RANSfORTATION/CI~ATION: Could the proposal result in: a. An increase in traffic that is greater than the land use designated on the General Plan? b. Use of existing, new, parking structures? or demand for facilities/ c,. Impact upon existing public transportation systems? d. Alteration of present patterns of circulation? e. Impact to rail or air traffic? f. Increased safety hazards to vehicles, bicyclists or pedestrians? "- REVISED 10/87 - Yel; No x x x x x x x x x x ~ PAGE 4 OF 8 ~ .!... - J::.. - .a '" J'" . o g. A disjointed pattern roadway improvements? h. Other? 10. ~~C SERVICES Will the proposal impact the following beyond the capability to provide adequate levels of service? a. Fire protection? Police protection? Schools (i.e. attendance, boundaries, overload, etc.)? b. c. d. Parks or other recreational facilities? e. Medical aid? f. Solid waste? g. Other? 11. ~!LITIES: Will the proposal: a. Impact the following beyond the capability to provide adequate levels of service or require the construction of new facilities? 1. Natural gas? 2. Electricity? 3. Water? 4. Sewer? 5. Other? b. Result in a pattern of extensions? disjointed utility c. Require the construction of new facilities? REVISED 10/87 .~. of oYes . No y y y x x x x x x X X x X Maybe ""Il ~ PAGE 5 OF 8 .- Maybe ""Il ~ 12. AESTHETI~: a. Could the proposal result in the obstruction of any scenic view? b. Will the visual impact of the project be detrimental to the surrounding area? c. Other? 13. ~Y~~URA~--F~QURCES: proposal result in: a. The alteration or destruction of a prehistoric or historic archaeological site? Could the b. Adverse impacts historic object? c. Other? physical or aesthetic to a prehistoric or site, structure or 14. Mandatory Findings of Significance (Section 15065) " The California Environmental Quality Act states that if any of the following can be answered yes or maybe, the project may have a significant effect on the environment and an Environmental Impact Report shall be prepared. a. Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate -- Yes No x x x x REVISED 10/87 PAGE 6 OF 8 ~ - - r ~ - -Yes No Maybe ""Il important examples of the major periods of .California history or prehistory? b. Does the project have the potential to achieve short term, to the disadvantage of long-term, environmental goals? (A short-term impact on the environment is one which occurs in a relatively brief, definitive period of time while long-term impacts will endure well into the future. ) c. Does the project have impacts which are individually limited, but cumulatively considerable? (A project may impact on two or more separate resources where the impact on each resource is relatively small, but where the effect of the total of those impacts on the environment is significant. ) d. Does the project have environmental effects which will cause substantial adverse effects on human beings, either directly or indirectly? C. DISCUSSION OF ENVIRONMENTAL EVALUATION AND MITIGATION MEASURES (Attach sheets as necessary.) x x x x l"" I ....~ 1.""".1 "",I.__l " ~ REVISED 10/87 PAGe 7 OF 8 .h. - - V DETERMINAT10N On the basis of this initial study, The proposed project COULD NOT have a significant effect on the environment and a NEGATIVE DECLARATION will be prepared. u " GJ o The proposed project could have a significant effect on the environment, although there will not be a significant effect in this. case because the mitigation measures described above have been added to the project. A NEGATIVE DECLARATION will be prepared. The proposed project MAY have a Significant effect on the environment, and an ENVIRONMENTAL IMPACT REPORT is required. o ENVIRONMENTAL REVIEW COMMITTEE CITY OF SAN BERNARDINO, CALIFORNIA ~ r1(J~ - {)A~ Name and Title ,5f1A I ~ ~(a.kI. V\ QA. Signature Date: A.{~ 1- i (q?{ 110... ~ ReVIseD 12/87 PAGe 8 OF 8