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2001-7056 GENGINEERING SERVICES DEPARTMENT Capital Improvement Projects city of District Support Services Encinitas Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering November 20, 2003 Attn: Gulf Insurance Company 110 West "A" Street Suite 1805 San Diego, California 92101 RE: Jeff Creighton 1192 Via Di Felicita APN 264-151-20 Grading Permit 7056-G Partial release of security Permit 7056-G authorized earthwork, storm drainage, and erosion control, all needed to build the described project. The Field Operations Division has approved the grading. Therefore, release of the security deposit is merited. Performance Bond B36005254, in the remaining amount of $13,860.00, is hereby fully exonerated. The document original is enclosed. Should you have any questions or concerns, please contact Debra Geishart at (760) 633- 2779 or in writing, attention this Department. Sincerely, Masih Maher Senior Civil Engineer J4 I em ach Finance Manager Financial Services Cc: Jay Lembach, FinanceManager Creighton, Jeff Debra Geishart file enc. TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 ~ recycled paper City OoNGINEERING SERVICES DEPARTMENT Encinitas Capital Improvement Projects District Support Services Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering May 7, 2003 Attn: Gulf Insurance Company 110 West "A" Street Suite 1805 San Diego, California 92101 RE: Jeff Creighton 1192 Via Di Felicita APN 264-151-20 Grading Permit 7056-G Partial release of security Permit 7056-G authorized earthwork, storm drainage, single driveway, and erosion control, all needed to build the described project. The Field Operations Division has approved the rough grading. Therefore, a reduction in the security deposit is merited. Performance Bond B36005254 in the amount of $55,440.00, may be reduced by 75% to $13,860.00. The document original will be kept until such time it is fully exonerated. The retention and a separate assignment guarantee completion of finish grading. Should you have any questions or concerns, please contact Debra Geishart at (760) 633- 2779 or in writing, attention this Department. Sincerely, • Masih Maher Senior Civil Engineer Field Operations )ay mbach Finance Manager Financial Services CC Jay Lembach, Finance Manager Jeff Creighton Debra Geishart File TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 ~ recycled paper HYDROLOGY & HYDRAULIC CALCULATIONS CREIGHTON RESIDENCE APN 264-151-20 DATE: MAY 21, 2001 PREPARED BY: SAN DIEGUITO ENGINEERING, INC. 4407 MANCHESTER AVE, SUITE 105 ENCINITAS, CA 92924 MAY ` 2001 PROJECT NAME: CREIGHTON RESIDENCE PROJECT NUMBER: SDE 4635 COMMENT: G- COORD: N33-03-45 E117-13-30 100 YEAR STORM P6 (in): 3.00 P24 (in): 5.30 P6/P24: 0.57 ADJUSTED P6: 3.00 SOIL TYPES <HYDRO SOIL GROUP> D RUNOFF COEFF - C 0.45 WATERS DESIGNA [j a] C Tc min FLihoL =cfs cfs A 11760 0.27 0.45 5.0 7.90 0.96 3165 0.07 0.90 5.0 7.90 0.52 1.48 B 13750 0.32 0.45 5.0 7.90 1.12 1.12 C 7175 0.16 0.45 5.0 7.90 0.59 7785 0.18 0.90 5.0 7.90 1.27 1.86 D 1000 0.02 0.45 5.0 7.90 0.08 0.08 E 1465 0.03 0.45 5.0 7.90 0.12 5510 0.13 0.90 5.0 7.90 0.90 1.02 TABLE 2 RUNOFF COEFFICIENTS (RATIONAL METHOD) DEVELOPED AREAS (URBAN) Coefficient. C Land Use Sol ' Group TI-) Residential: - A 9 C D Single Family .40 .45 .50 .55 Multi-Units .45 .50 .6o .70 Mobile homes .45 .50 .55 .65 Rural (lots greater than 1/2 acre) .30 .35 40 • 4 5 Commercia1(2) .70 .75 .80 85 809, Impervious . Industrial (2) .80 .85 .90 95 90% Impervious . NOTES (')Soil Group mans are available at the'affices of the Department of Public Works. (2)Where actual conditions deviate significantly from the tabulated impervious- ness values of 809; or 90%, the values given for coefficient C, may be revised by multiplying 80% or 909; by the ratio of actual imperviousness to the tabulated imperviousness. However, in no case shall the final coefficient be less than 0.50. For example: Consider commercial property on D soil,-group. Actual imperviousness = 507. Tabulated imperviousness = 80%o Revised C 800 x 0.85 = 0.53 IV-A-9 APPENDIX IX-B Rev. S/81 Ck: G V z :mss . 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O r- i- WA°" WA ~ W cz H ~ O Q 4 ~r ( t z I ~ 0 OF l O H } ¢ O O t+..zz O W O tj O W J V 0 ~ S 0 M M s L. e! e L'1 - d Sao - < y _ a _ CL u1 U t p O S p Col. u- tri o u i < j C O_ N < Q Z F N i v vv 16 I I-;.-13 AREA A+B MIN SLOPE Worksheet for Circular Channel Project Description Worksheet AREA A+B MIN Flow Element Circular Channc Method Manning's Fora Solve For Channel Depth Input Data Mannings Coeffic 0.016 Slope 0 87000 ft/ft Diameter 24 in - S -NOT Discharge 2.60 cfs 1 Results Depth 0.30 ft Flow Area 0.3 ft2 Wetted Perime 1.59 ft Top Width 1.42 ft Critical Depth 0.56 ft Percent Full 14.9 % Critical Slope 0. 006755 ft/ft Velocity 8.88 ft/s Velocity Head 1.23 ft Specific Energ, 1.52 ft Froude Numbe 3.45 Maximum Disc 58.32 cfs Discharge Full 54.21 cfs Slope Full 0.000200 ft /ft Flow Type supercritical Project Engineer: San Dieguito Engineering, Inc u:\ldata\engineering\4635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 (614ej 05/21/01 11:25:03 AM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 AREA A+B MAX SLOPE Worksheet for Circular Channel Project Description Worksheet AREA A+B MA) Flow Element Circular Chann( Method Manning's Fora Solve For Channel Depth Input Data Mannings Coeffic 0.015 Slope 0.180000 ft/ft ~~S1 Diameter 24 in ~ k, V Discharge 2.60 cfs Results Depth 0.24 ft Flow Area 0.2 ft2 Wetted Perime 1.42 ft Top Width 1.31 ft Critical Depth 0.56 ft Percent Full 12.1 % Critical Slope 0.005937 ft/ft Velocity 11.99 ft/s Velocity Head 2.23 ft Specific Energ, 2.48 ft Froude Numbe 5.19 Maximum Disc 89.47 cfs Discharge Full 83.18 cfs Slope Full 0.000176 ft/ft Flow Type wpercritical J.1 tv-q,~ -PIP L t°, 7'Jri4 t=2~~ j &)iey~ViZ C1LTCZ Project Engineer: San Dieguito Engineering, Inc u:\ldata\engineering44635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 [614e] 05/21/01 11:24:26 AM 0 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 AREA C MIN SLOPE AT OUTLET Worksheet for Circular Channel Project Description Worksheet AREA C MIN SLOPE. Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coeffic 0.016 Slope D, 005000 ft/ft Diameter 24 in -~S TLI U ja Discharge 1.86 cfs Results Depth 0.25 ft GV}}~V1tYl f~~ 01C„ Flow Area 0.2 ft' Wetted Perime 1.44 ft Top Width 1.32 ft Critical Depth 0.47 ft Percent Full 12.4 % Critical Slope 0.006818 ft/ft Velocity 8.29 ft/s --lbp Velocity Head 1.07 ft Specific Energ, 1.32 ft Froude Numbe 3.54 Maximum Disc 60.94 cfs Discharge Full 56.65 cfs Slope Full 0.000102 ft/ft Flow Type Supercritical C v ~r~-cur ,21 ~,v - I ~ , r = - ' 0 T 1A Project Engineer: San Dieguito Engineering, Inc u:\1 data\engineering\4635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 (614e] 05/21/01 09:42:56 AM 0 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 AREA C AT BEND Worksheet for Circular Channel Project Description Worksheet AREA C AT BE Flow Element Circular Chann Method Manning's Forr Solve For Channel Depth Input Data Alannings Coeffic 0.015 S ope 130000 ft/ft Diameter 24 in Discharge 1.86 cfs Results Depth 0.22 ft Flow Area 0.2 ft' Wetted Perime 1.36 ft Top Width 1.26 ft Critical Depth 0.47 ft Percent Full 11.2 % Critical Slope 0.005992 ft/ft Velocity 9.68 ft/s Velocity Head 1.46 ft Specific Energ, 1.68 ft Froude Numbe 4.37 Maximum Disc 76.04 cfs Discharge Full 70.69 cfs Slope Full 0.000090 ft/ft Flow Type supercritical .3b0u2t-c:Ur~m u Je Cy2T C3 1.3 L9.7>Z Z~ = or~2' Project Engineer: San Dieguito Engineering, Inc u:\ldata\engineering44635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMasterv6.0 [614e] 05/21/01 09:42:40 AM 0 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 AREA D, NORMAL DEPTH Worksheet for Circular Channel Project Description Worksheet AREA D NORM/ Flow Element Circular Channe Method Manning's Form Solve For Channel Depth Input Data Mannings Coeffic 0.011 Slope 0.020000 ft/ft Diameter 4 in Discharge 0.08 cfs Results Depth 0.11 ft Flow Area 2.6e-2 ft2 Wetted Perime 0.42 ft Top Width 0.32 ft Critical Depth 0.16 ft Percent Full 34.2 % Critical Slope 0.006169 ft/ft Velocity 3.03 ft/s Velocity Head 0.14 ft Specific Energ: 0.26 ft Froude Numbe 1.85 Maximum Disc 0.34 cfs Discharge Full 0.32 cfs Slope Full 0.001265 ft/ft Flow Type supercritical Project Engineer: San Dieguito Engineering, Inc u:\1 data\engineering44635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 [614e] 05/21/01 11:32:28 AM C) Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 AREA D, CRITICAL DEPTH Worksheet for Circular Channel Project Description Worksheet AREA D CRITICA Flow Element Circular Channel Method Manning's Formul Solve For Channel Depth Input Data Mannings Coeffic 0.011 Slope 0, 006169 ft/ft Diameter 4 in Discharge 0.08 cfs Results Depth 0.16 ft Flow Area 4.1 a-2 ft' Wetted Perime 0.50 ft Top Width 0.33 ft Critical Depth 0.16 ft Percent Full 47.2 % Critical Slope 0.006169 ft/ft Velocity 1.97 ft/s Velocity Head 0.06 ft Specific Energ, 0.22 ft Froude Numbe 1.00 Maximum Disc 0.19 cfs Discharge Full 0.18 cfs Slope Full 0.001265 ft/ft Flow Type 3ubcritical G 0'(G -7 1 Project Engineer: San Dieguito Engineering, Inc u:\ldata\engineering\4635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 [614e] 05/21/01 11:33:28 AM 0 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 ROAD SECTION Worksheet for Triangular Channel Project Description Worksheet ROAD SECTIO Flow Element Triangular Char Method Manning's Furrr Solve For Channel Deptn Input Data Mannings Coeffic 0.016 Slope 043000 ft/ft Left Side Slope 50.00 H : V Right Side Slope 0.33 H : V Discharge 1.02 cfs Results Depth 0.12 ft Flow Area 0.4 ft' Wetted Perim 6.04 ft Top Width 5.95 ft Critical Depth 0.16 ft Critical Slope 0.0 08841 ft/ft Velocity 2.90 ft/s Velocity Head 0.13 ft Specific Enerc 0.25 ft Froude Numb. 2.10 Flow Type supercritical 0 MLoA (4--5 1 L Project Engineer: San Dieguito Engineering, Inc u:\ldata\engineering44635\drainage\4635.fm2 San Dieguito Engineering, Inc FlowMaster v6.0 [614e] 05/21/01 11:38:29 AM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 QP SCALE 1" = 40' U C7 Z Z Z Z o Q w UJ LO CL ' z C J ' z ) -cq wN~ W Z Z F- 0) 1- W w<- l " a ~ O Zr ° w cl) Z 0 ° Z w Z = Z Ewa L o J_ Z > ~ U U" WOltM \VvC,WLI JA-kN, Iq (Ci'~-S `be(VY~> A4L3- REPORT OF GRADING OBSERVATION, SOIL TESTING AND GEOTECHNICAL ENGINEERING Creighton Residence Proposed Remodel and Additions 2902 Lone Jack Road Encinitas, California JOB NO. 00-7780 09 July 2003 Prepared for: Mr. And Mrs. Jeff Creighton OrF4 OP IGEOTECHNICAL EXPLORATION, INC. SOIL & FOUNDATION ENGINEERING • GROUNDWATER HAZARDOUS MATERIALS MANAGEMENT • ENGINEERING GEOLOGY 09 July 2003 Mr. and Mrs. Jeff Creighton 2902 Lone Jack Road Encinitas, CA 92024 Job No. 00-7780 Subject: Report of Grading Observation, Soil Testing and Geotechnical Engineering Creighton Residence Proposed Remodel and Additions 2902 Lone Jack Road Encinitas, California Dear Mr. and Mrs. Creighton: As requested, Geotechnical Exploration, Inc., hereby submits the following report summarizing our work and test results, as well as our conclusions and recommendations concerning the subject project. Representatives of our firm observed the recent rough grading operation and tested the fill soils that were removed and recompacted during the building of a buttress fill on the north side slope, and the preparation of the upper pad area for exterior proposed improvements. The grading described herein consisted of removing and recompacting on-site soils, and placing and compacting imported soils to stabilize the north slope in front of the existing residence and in the top of the slope area around the existing residence. The grading reported herein was observed and/or tested between March 21 and May 28, 2003. SCOPE OF WORK The scope of work of our services included: 7420 TRADE STREET • SAN DIEGO, CA 92121 • (858) 549-7222 • FAX: (858) 549-1604 - E-MAIL: geotech@ixpres.com Creighton Residence Job No. 00-7780 Encinitas, California -Page 2 1. Observations during grading at the site. 2. Performing field density tests in the placed and compacted fill. 3. Performing laboratory tests on representative samples of the fill material. 4. Providing geotechnical consultation and geological observations during grading, as requested by the owner and/or grading contractor, and as needed when site soil conditions required it. 5. Providing professional opinions, conclusions, and recommendations regarding the observed grading and the pending work. GENERAL SITE INFORMATION The property, consisting of approximately 2.3 acres, is located at 2902 Lone Jack Road, at a parcel known as Assessor's Parcel No.264-151-20 or Lot No.18 of Rancho Las Encinitas, according to Map No.848, in the City of Encinitas area of the County of San Diego (see Figure No. I). The property is bordered on the north by a driveway and a natural drainage channel, on the south by undeveloped residential property, on the west by property being developed and the former location of Lone Jack Road, and on the east by developed residential property. Prior to grading, the property included a level building pad bounded to the north by a moderately to steeply sloping, north-facing hillside with several level benches cut into the northern slope. Approximate elevations across the site ranged from a high around to 218 feet above mean sea level (MSL) to 170 feet above MSL. Precise mapped survey information concerning actual elevations after grading was not available at the time of this report preparation. Approximate elevations presented in Creighton Residence Job No. 00-7780 Encinitas, California • Page 3 our Plot Plan, Figure No. II, were obtained approximately by our field representative with a hand level. Existing structures on the site prior to this grading included a single-story, single family residence, with a detached garage, and another separate structure. Existing vegetation prior to grading consisted of primarily of native weeds and shrubbery, and several large eucalyptus and other trees. The site north slope in front of the existing residence has been stabilized by the new buttress fill, and the new improvement/addition area has been prepared to receive the new addition. It is our understanding that the building will be constructed in conformance with the California Building Code, utilizing conventional-type founda- tions, footings, and building materials. A Plot Plan illustrating the approximate location of all our tests taken throughout the grading operation is enclosed as Figure No. II. Work that remains to be completed at the site and that will require our observations and/or testing include any retaining wall backfill, trench backfill, R-value testing for paved areas, and final subgrade and base preparation of areas to receive pavement. FIELD OBSERVATIONS Periodic tests and observations were provided by a representative of Geotechnical Exploration, Inc. to check the grading contractor's (Mr. Mike Scott) compliance with the drawings and grading specifications. The presence of our field representatives at the site was to provide to the client a continuing source of professional advice, opinions, and recommendations based upon the field representative's observations of the contractor's work, and did not include any a4kj Creighton Residence Encinitas, California Job No. 00-7780 • Page 4 superintending, supervision, or direction of the actual work of the contractor or the contractor's workers. Our visits were made on request of the owner or the contractor's representative. The grading operation was observed to be performed in the following general manner: 1. Prior to placing any compacted fill, the areas to be graded were cleared of any miscellaneous debris, and/or vegetation, and hauled off-site. 2. Uncompacted fills, soft or disturbed materials, and/or unsuitable soils were removed to expose firm ground. In the buttress fill area, the removed material was extended below the encountered slide plane. In the upper part, in the building pad area, the soil removal was extended to a depth of at least 3 to 4 feet below the existing grades, and to at least the approximate limits shown in the attached Plot Plan, Figure No. II. In the buttres fill area, the keyway was essentially the bottom length of the entire buttress. The excavation extended at least 2 to 3 feet below the observed slide plane into firm bearing soil. In some areas, the bottom of the excavation extended 4 to 5 feet below the slide plane. The plan view dimensions of the buttress key ranged from 70 to 90 feet in width by 160 feet in length. Due to the grading restrictions on the width extension of the buttress, the thickness of the buttress had to be increased during grading. Another factor influencing the dimensions was the instability of the upper soils of the excavation as it got closer to the residence. The backcut of the excavation in these unstable areas was made at 1.5 to 1.0 (horizontal to vertical) slope Creighton Residence Encinitas, California Job No. 00-7780 • Page 5 ratio. The excavation was unstable in the area closer to the house due to the presence of a septic tank and leach lines that had trenches backfilled with gravel. During grading of the buttress there were several rainstorms that slowed down the backfilling of the excavation. Sump pumps had to be used to drain collected water at the bottom of the excavation. A subdrain consisting of 4-inch perforated pipe placed in an envelope of crushed rock gravel wrapped in filter cloth was placed to range from 180 to 170 feet in elevation from the southwest to the northwest discharge point. The transition from perforated pipe to solid pipe occurred at the west end of the buttress, at an elevation of 178 feet above MSL. 3. The exposed ground surface of the excavation or areas excavated to receive fill were scarified at least 6 inches and uniformly recompacted prior to placement of compacted soil 4. Areas to receive compacted fill were, in general, observed and evaluated by our field representative prior to placing compacted fill. In slope fill areas, adequate benching was provided by keying into firm natural ground or approved compacted fill as the compacted fill was placed above the toe area. 5. Soils approved for use in the compacted fill were placed in horizontal layers not exceeding approximately 8 inches in loose thickness. 6. Fill material was watered or dried at or near optimum moisture content, and mixed prior to compaction. Potentially expansive fill soils were compacted at a moisture content of 5 percent above the optimum. Creighton Residence Encinitas, California Job No. 00-7780 .Page 6 7. The soils utilized in the grading operation were from on-site and imported and consisted primarily of silty clays, clayey silt, silty sands. Some concrete chunk pieces, up to 1 foot maximum dimension, existing at the site as product of construction demolition, were allowed to be mixed and placed in the deeper parts of the buttress fill. 8. Fill materials were tested at specific test locations and found to be compacted to at least 90 percent of Maximum Dry Density. 9. Compaction was achieved by drying or wetting the soil, mixing it and rolling it with heavy construction equipment such as a Cat D-8, Cat D-6 dozers, and rubber tired loader, and an excavator. Moisture conditioning of the soil was provided with a water hose. 10. The method used to compact the slope fill surface consisted of walking it with a track-mounted dozer. 11. Field density tests were taken at the approximate locations shown on the plot plan (Figure No. II). TESTS Field density tests were performed in accordance with ASTM D1556. Maximum density determinations were performed in accordance with ASTM D1557. The relative compaction results, as summarized on Figure No. III, are the ratios of the field densities to the laboratory Maximum Dry Densities, expressed as percentages. Direct shear tests were performed in accordance with ASTM D3080. Creighton Residence ]ob No. 00-7780 Encinitas, California -Page 7 CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based upon our analysis of all data available from the testing of the soils compacted on this site. Our observations of the grading operation (while in progress), our field and laboratory testing of the typical bearing soils, and our general knowledge and experience with the natural-ground soils and recompacted fill soils on this site were utilized in conducting our services. A. General Grading 1. The soils utilized in the grading operation were from existing on-site soils that were removed and recompacted, and imported materials that were placed and recompacted. The soils consisted primarily of silty clays, clayey silts, and silty sands. Clayey soils of this type are considered to range from medium to highly expansive, as measured by the CBC Expansion Index Test (29-2 standard). 2. During the grading operation, the natural-ground soils were exposed (where necessary and feasible) and properly prepared to receive the fill soils. The fill soils were placed, watered, compacted, and then tested at specific test locations, and were found to be compacted at the tested locations to at least 90 percent of Maximum Dry Density, in accordance with the requirements of the City of Encinitas. The maximum depth of fill soils placed on this site at the time of the grading operation monitored by this firm was not in excess of 35 feet in vertical thickness. 3. Any surplus, loose, stockpiled soils remaining at the property should be removed and hauled off the site. G PI W' Creighton Residence Encinitas, California Job No. 00-7780 • Page 8 4. Grading work that needs to be completed and performed under our observations and testing include any retaining wall backfill, trench backfill, and finish subgrade and base preparation in areas to receive pavement. B. Foundations and Slabs On-Grade 5. The continuous foundations and spread footings shall extend a minimum depth of 18 inches into the firm natural ground or properly compacted fill, and have a minimum width of 12 inches. The continuous foundations shall be reinforced with at least four No. 5 steel bars; two bars shall be located near the top of the foundations and two bars 3 inches from the bottom. Additional steel may be required by the structural engineer in deeper footings. 6. Prior to pouring footings and foundations, and prior to placement of floor slab base sections, any clayey soils shall be thoroughly watered such that they approach their maximum potential for expansion. We recommend that the clayey subgrade soil, if present on the excavation or subgrade, be presoaked to achieve a moisture content at least 5 percent above optimum to a depth of at least 1 foot below the bottom of slab and footings. The subgrade moisture content and penetration should be verified by our field representative within 48 hours prior to concrete pouring. The bottom of the foundation excavation should be firm, not muddy, and have the acceptable moisture content. 7. Concrete floor slabs, if used, shall be at least 5 inches thick and be founded on at least 2 inches of sand overlying a reinforced moisture barrier or 10-mil visqueen. The slabs shall be reinforced with at least No.3 steel reinforcing bars placed on 18-inch centers. Any steel reinforcement should be placed in so" W Creighton Residence Encinitas, California Job No. 00-7780 • Page 9 the middle of the floor slab section. Proper supports should be used to keep the steel reinforcement separated from the base or soil subgrade. 8. We recommend that all nonstructural concrete slabs (such as patios, sidewalks, etc.), be founded on properly compacted and moisture conditioned soils. Proper shrinkage joints (sawcuts) should be provided and spaced no farther than 12 feet or the width of the slab, whichever is less, and at re- entrant corners. The sawcuts should be performed no later than 24 hours after pouring, or as soon as the concrete is set. Sawcuts should be deepened to at least one-quarter of the thickness of the slab. If steel reinforcement (such as No 3 steel bars at 18 inches between centers) is provided for the slabs, the control joints may be spaced up to 20 feet apart. 9. All concrete (flatwork) slabs or rigid improvements should be built on properly compacted and approved subgrade and/or base material. Geotechnical Exploration, Inc. will accept no liability for damage to flatwork or rigid improvements built on untested or unapproved subgrade or base material. C. Foundation Design Parameters 10. The recommended allowable soil bearing capacity of the properly compacted fill soils placed on the site is 2,000 pounds per square foot (psf) for compacted fill and 3,000 psf for formational soils. The recommended allowable soil bearing capacity may be increased 800 psf for each additional foot in depth, and 400 psf for each additional foot in width. The total bearing capacity shall not exceed 4,000 psf. This soil-bearing value may be increased one-third for design loads that include wind or seismic analysis. Additionally, these bearing capacities may be utilized in the design of foundations and GH PAL Creighton Residence Encinitas, California Job No. 00-7780 Page 10 footings of the proposed structure when founded a minimum of 18 inches into the firm natural ground or compacted fill for the proposed structures. For on-site conditions, it is expected that the maximum settlement of the new residential structure will not exceed 1 inch, and the maximum differential angular rotation will not exceed 1/240. 11. The passive earth pressure of the encountered natural-ground soils and well- compacted fill soils (to be used for design of building foundations and footings to resist the lateral forces) shall be based on an Equivalent Fluid Weight of 250 pounds per cubic foot for compacted fill and 300 pcf for formational soils. This passive earth pressure shall only be considered valid for design if the ground adjacent to the foundation structure is essentially level for a distance of at least three times the total depth of the foundation, the soil is properly compacted fill or natural dense material, and the concrete is poured tight against the walls of the excavation. 12. A Coefficient of Friction of 0.35 times the dead load may be used to calculate the total friction force between the bearing soils and the bottom of concrete wall foundations, or structure foundations, or floor slabs. D. Retaining Wall Design Parameters 13. The active earth pressure (to be utilized in design of cantilever walls, etc.) shall be based on a Equivalent Fluid Weight of 38 pounds per cubic foot (for level backfill only and very low to low-expansive, on-site native soils or imported soils). Creighton Residence Encinitas, California Job No. 00-7780 Page 11 In the event that the cantilever retaining wall is surcharged by sloping backfill, the design active earth pressure shall be based on the appropriate Equivalent Fluid Weight presented in the following table: *To determine design active earth pressures for ratios intermediate to those presented, interpolate between the stated values. In the event that a retaining wall is to be designed for a restrained condition, a uniform pressure equal to 9xH (nine times the total height of retained soil, considered in pounds per square foot) shall be considered as acting everywhere on the back of the wall, in addition to the design Equivalent Fluid Weight. The design pressures presented above are based on utilization of an uncontrolled mixture of low-expansive soil imported soil used in backfill operations. Additional surcharge pressures to be considered in the wall design include any loads applied within the failure block retained by the wall. E. Cut and Fill Slopes 14. Natural-ground cut slopes of maximum inclinations of 2.0 horizontal to 1.0 vertical, and compacted fill slopes of maximum inclinations of 2.0 horizontal to 1.0 vertical, in the area of the residence and retained by the new buttress fill shall be stable and free from deep-seated failures for materials native to the site and utilized in compacted fills. IML as SKI Creighton Residence Encinitas, California Job No. 00-7780 Rage 12 15. Although the compacted fill soils have been verified at the tested locations to a relative compaction of 90 percent of Maximum Dry Density or better, the compacted fill soils that occur within 8 feet of the face of the fill slope may posses poor lateral stability. If not properly founded, the proposed structures and associated improvements (such as walls, fences, patios, sidewalks, swimming pools, driveways, asphalt paving, etc.) that are located within 8 feet of the face of compacted fill slopes could suffer differential movement as a result of the poor lateral stability of these soils. The foundations and footings of the proposed structures, fence posts, walls, etc., when founded 8 feet and farther away from the top of compacted fill slopes, may be of standard design in conformance with the recommended soil value. If proposed foundations and footings are located closer than 8 feet inside the top of compacted fill slopes, they shall be deepened to at least 1.5 feet below a line beginning at a point 8 feet horizontally inside the fill slopes, and projected outward and downward, parallel to the face of the fill slopes (see Figure No. IV). 16. We recommend that all compacted fill slopes and natural cut slopes be planted with an erosion-resistant plant, in conformance with the requirements of the City of Encinitas. F. Drainage 17. Adequate measures shall be taken to properly finish-grade the site after the structure and other improvements are in place. Drainage waters from this site and adjacent properties are to be directed away from foundations, floor slabs, footings, and slopes, onto the natural drainage direction for this area into properly designed and approved drainage facilities. Roof gutters and Creighton Residence Encinitas, California Job No. 00-7780 Page 13 downspouts should be installed on all structures, and the runoff directed away from the foundations and slopes via closed drainage lines. Proper subsurface and surface drainage will help minimize the potential for waters to seek the level of the bearing soils under the foundations, footings, and floor slabs. Failure to observe this recommendation could result in uplift or under- mining and differential settlement of the structure or other improvements on the site, and other moisture related problems. 18. Proper subdrains shall be installed behind any retaining and restrained retaining walls, in addition to proper waterproofing of the back of the walls. The drainage of said subdrains shall be directed to the designed drainage for the project or the natural drainage for the area. 19. It should be noted that changes of surface and subsurface hydrologic conditions, plus irrigation of landscaping or significant increases in rainfall over the "accepted average-annual" rainfall for San Diego County in past years, may result in the appearance of minor amounts of surface or near- surface water at locations where none existed previously. The damage from such water is expected to be minor and cosmetic in nature, if corrected immediately. Corrective action should be taken on a site-specific basis if, and when, it becomes necessary. 20. Planter areas, flower beds, and planter boxes shall be sloped to drain away from the foundations, footings, and floor slabs. Planter boxes shall be constructed with a sealed bottom, and be provided with sufficient area drains and a subsurface drain installed in gravel, with the direction of subsurface and surface flow away from the foundations, footings, and floor slabs, to an adequate drainage facility. Creighton Residence Job No. 00-7780 Encinitas, California Page 14 21. Any backfill soils placed adjacent to or close to foundations, in utility trenches, or behind retaining walls, that support structure and other improvements (such as patios, sidewalks, driveways, pavements, etc.), other than landscaping in level ground, shall be compacted to at least 90 percent of Maximum Dry Density. It is recommended that Geotechnical Exploration, Inc, observe and test the backfill during placement. Geotechnical Exploration, Inc. will accept no liability for damage to structures that occurs as a result of improperly backfilled trenches or walls, or as a result of fill soils placed without our observations and testing. G. Miscellaneous Recommendations 22. Following placement of concrete floor slabs, sufficient drying time must be allowed prior to placement of floor coverings. Premature placement of floor coverings may result in degradation of adhesive materials and loosening of the finish-floor materials. 23. Swimming pools and/or subsurface structures that are founded in any potentially expansive clay soils shall be properly designed by a structural engineer and/or soils engineer. 24. The remaining soil work to be completed at the site (such as trench and retaining wall backfill, exterior hardscape improvement subgrade preparation, area to be paved final subgrade and base preparation, etc.) should be performed under our observations and testing. ~r~ Creighton Residence Job No. 00-7780 Encinitas, California Page 15 25. We also recommend that all footing excavations be observed by a representative of this firm prior to placing concrete, to verify that footings are founded on satisfactory soils for which the recommendations expressed in the soil investigation report remain applicable. SUMMARY Based on our field testing and grading observation, it is our opinion that the grading operation described herein, in general, was performed in conformance with the City of Encinitas Grading Ordinance, and in general accordance with our recommendations. It is to be understood that our test results and opinion of general acceptance do not guarantee that every cubic yard of compacted fill has been compacted to specification since not every cubic yard has been observed or tested. Our test results indicate the measured compaction degree obtained at the specific test location. We can only attest that our tests and observations have been made in accordance with the care and current professional standards in our field. All observed or tested work done during the grading operation appears, in general, to have been performed in accordance with the soil investigation report for this site, issued by our firm and dated July 06, 2000, and our "Revised Buttress Configuration Report," dated April 30, 2003 (Job No. 00-7780). The grading described herein was observed and/or tested between March 21 and May 28, 2003. All statements in the report are applicable only for the grading operation observed by our firm, and are representative of the site at the time of our final site visit before the report was prepared. The firm of Geotechnical Exploration, Inc. shall not be held responsible for fill soils placed without our observations and testing at any other time, or for subsequent changes to the site by others, which directly or Creighton Residence Encinitas, California Job No. 00-7780 Page 16 indirectly cause poor surface or subsurface drainage, water erosion, and/or alteration of the strength of the compacted fill soils. In the event that any changes in the nature, design, or location of the building or improvements are planned, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and the conclusions of this report modified or verified in writing. Professional opinions presented herein have been made based on our tests, observations, and experience, and they have been made in accordance with generally accepted current geotechnical engineering principles and practices within the County of San Diego. This warranty is in lieu of all other warranties, either expressed or intended. Thank you for this opportunity to be of service. Should any questions arise concerning this report, please do not hesitate to contact us. Reference to our Job No. 00-7780 will help to expedite a reply to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. ~ pFESS/p,,, CFA No. 002007 l rn Exp.9r'30 03 Cpl F ~F C Jaime A. Cerros, P.E. R.C.E. 34422/G. E. 2007 Senior Geotechnical Engineer JAC/pj cc: Addressee (4) Figure Number I, Job Number 00-7780 Z p mocv~ U J _ a°'o0 Q W 0C 0ad a. _ o u. w o" Q1 Q O O ~ ~ ~ ° p -0 4) z z 7 N Cv L Z' r o O O w o oc = ~ c E m Z •tS Q Q X a. 0 0 LU 0 4) *a cc > J U ~ Q c6 a- pp U Q~ n Q p o 1 1-- w o v occ ~ ~ o zz o oc0 a CL w N <L g Q a o o-o X ;r w 0 Z O Q- O a.a Z ovaoN Y aZ p a~vEc O 43 'a+~: H a.w Q p~ x a,~ ~Z~ Qp m NW W ~Q~rn a a. Lr 3Oa" m'. ' = Ds 2 zaEom 1 ~ I p m_ i I N O I g pot • Ol O ^ I o b ~ J is a 0,0 1 C-41 O ~ ~ t~ IJ ~ N 1, l.0 ~ J ig- ~ r iG• o I (31, I O / cJ CC) / I / z J O ~ OnC I -1 11 U I N Y 0 ~ Uwe i own is l7 z H X W O t7 CX X: li ~ prq q liq QzO LLJ d ¢ O L~ LL, w I-- W W d N H CL Q U W 3 z x N ar rQ roaz C3 q C3 -J W U A W (n~Q' = O q aLJ U a W OC W - L~ I OC H O COMPACTION TEST RESULTS TEST DATE LOCATION DEPTH/ ELEVATION OF FILL MOISTURE M FIELD DENSITY SOIL TYPE RELATIVE COMPACTION 1 3/26/03 Buttress fill 169' 23.1 100 pcf II 93% 2 3/26/03 Buttress fill 169.5' 21.0 99 pcf II 92% 3 3/27/03 Buttress fill 171' 19.6 100 pcf II 93% 4 3/27/03 Buttress fill 172' 19.9 102 pcf II 94% 5 3/28/03 Buttress fill 174' 21.3 100 pcf II 93% 6 3/28/03 Buttress fill 176' 20.6 99 pcf II 92% 7 3/31 /03 Buttress fill 169' 19.8 100 pcf II 93% 8 3/31 /03 Buttress fill 171' 21.8 101 pcf II 94% 9 4/1 /03 Buttress fill 173' 23.0 102 pcf II 94% 10 4/1 /03 Buttress fill 175' 22.0 101 pcf II 94% 11 4/2/03 Buttress fill 172' 22.3 103 pcf II 95% 12 4/2/03 Buttress fill 174' 21.7 101 pcf II 94% 13 4/2/03 Buttress fill 177' 20.8 103 pcf II 95% 14 4/3/03 Buttress fill 178' 20.6 99 pcf II 92% 15 4/3/03 Buttress fill 180' 21.2 100 pcf II 93% 16 4/3/03 Buttress fill 178' 19.7 99 pcf II 92% 17 4/3/03 Buttress fill 180' 23.2 99 pcf II 92% 18 4/3/03 Buttress fill 182' 21.2 101 pcf II 94% 19 4/3/03 Buttress fill 182' 19.9 99 pcf II 92% 20 4/4/03 Buttress fill 183' 20.1 101 pcf II 94% 21 4/4/03 Buttress fill 184' 21.3 99 pcf II 92% 22 4/7/03 Buttress fill 185' 19.9 101 pcf II 94% CONTINUED Job No. 00-7780 Figure No. Ilia COMPACTION TEST RESULTS TEST DATE LOCATION DEPTH/ ELEVATION OF FILL MOISTURE 1%) FIELD DENSITY SOIL TYPE RELATIVE COMPACTION 23 4/7/03 Buttress fill 185' 21.2 101 pcf II 94% 24 4/9/03 Buttress fill 171' 21.5 102 pcf II 94% 25 4/9/03 Buttress fill 173' 22.3 102 pcf II 94% 26 4/10/03 Buttress fill 175' 19.8 100 pcf II 93% 27 4/10/03 Buttress fill 177' 20.6 101 pcf II 94% 28 4/11/03 Buttress fill 173' 22.1 100 pcf II 93% 29 4/1 1 /03 Buttress fill 180' 20.8 103 pcf II 95% 30 4/17/03 Buttress fill 173' 21.7 99 pcf II 92% 31 4/17/03 Buttress fill 174' 23.2 100 pcf II 93% 32 4/18/03 Buttress fill 176' 20.9 100 pcf II 93% 33 4/18/03 Buttress fill 178' 22.4 99 pcf II 92% 34 4/18/03 Buttress fill 180' 21.4 100 pcf II 93% 35 4/18/03 Buttress fill 173' 20.6 100 pcf II 93% 36 4/22/03 Buttress fill 175' 21.7 100 pcf II 93% 37 4/22/03 Buttress fill 177' 20.8 99 pcf II 92% 38 4/23/03 Buttress fill 179' 21.6 99 pcf II 92% 39 4/24/03 Buttress fill 181' 22.4 99 pcf II 92% 40 4/24/03 Buttress fill 182' 20.9 100 pcf II 93% 41 4/24/03 Buttress fill 183' 21.6 99 pcf II 92% 42 4/24/03 Buttress fill 184' 21.2 100 pcf II 93% 43 4/25/03 Buttress fill 185' 22.6 100 pcf II 93% 44 4/25/03 Buttress fill 185' 21.4 103 pcf II 95% CONTINUED Job No. 00-7780 661 Figure No. Illb COMPACTION TEST RESULTS TEST DATE LOCATION DEPTH/ ELEVATION OF FILL MOISTURE M FIELD DENSITY SOIL TYPE RELATIVE COMPACTION 45 4/28/03 Buttress fill 186' 20.2 102 pcf II 94% 46 4/28/03 Buttress fill 187' 19.4 101 pcf II 94% 47 4/28/03 Buttress fill 188' 21.0 100 pcf II 93% 48 4/29/03 Buttress fill 189' 21.6 100 pcf II 93% 49 4/29/03 Buttress fill 189' 19.9 100 pcf II 93% 50 5/1/03 Buttress fill 191' 20.8 98 pcf II 91% 51 5/1/03 Buttress fill 191' 21.7 101 pcf 11 94% 52 5/2/03 Buttress fill 193' 18.6 99 pcf IV 90% 53 5/2/03 Buttress fill 194' 20.1 102 pcf IV 93% 54 5/2/03 Buttress fill 196' 21.6 100 pcf IV 91% 55 5/2/03 Buttress fill 196' 19.4 101 pcf IV 92% 56 5/5/03 Buttress fill 197' 20.1 99 pcf IV 90% 57 5/5/03 Buttress fill 198' 22.6 102 pcf IV 93% 58 5/6/03 Buttress fill 199' 20.4 103 pcf IV 94% 59 5/6/03 Buttress fill 201' 21.1 102 pcf IV 93% 60 5/12/03 Patio 203' 22.4 100 pcf IV 91% 61 5/12/03 Patio 206' 21.0 101 pcf IV 92% 62 5/15/03 Driveway 215' 18.7 99 pcf IV 90% 63 5/15/03 Driveway 212' 19.9 101 pcf IV 92% 64 5/28/03 Building pad 208' 12.4 116 pcf V 93% 65 5/28/03 Building pad 209' 11.9 114 pcf V 91% 66 5/28/03 Building pad 210'/FG 10.6 115 pcf V 92% CONTINUED Job No. 00-7780 Figure No. Illb COMPACTION TEST RESULTS DEPTH/ MOISTURE FIELD SOIL RELATIVE TEST DATE LOCATION ELEVATION DENSITY TYPE COMPACTION OF FILL SOIL CLASSIFICATION TYPE DESCRIPTION O.M.C. MAX. DRY DENSITY II Green-gray, silty clay/clayey silt. 19.0% 105 pcf IV Green-tan, silty clay. 16.0% 110 pcf V Orange-brown, fine to medium silty sand. 11.0% 125 pcf Job No. 00-7780 Figure No. Illd Pi FOUNDATION REQUIREMENTS NEAR SLOPES PROPOSED STRUCTURE CONCRETE FLOOR SLAB \ SETBACK \ 8 ' 1 \ v REINFORCEMENT OF FOUNDATIONS AND FLOOR \ • SLABS FOLLOWING THE RECOMMENDATIONS OF THE ~ ARCHITECT OR STRUCTURAL ENGINEER CONCRETE FOUNDATION e ~ , 18" MINIMUM OR AS DEEP AS REQUIRED FOR LATERAL STABILITY TOP OF COMPACTED FILL SLOPE (Any loose soils on the slope surface shall not be considered to provide lateral or vertical strength for the footing or for slope stability. Needed depth of imbedment shall be measured from competent soil.) COMPACTED FILL SLOPE WITH MAXIMUM INCLINATION AS PER SOILS REPORT \ COMPACTED FILL OUTER MOST FACE OF FOOTING S, TYPICAL SECTION 8' (SHOWING PROPOSED FOUNDATION LOCATED WITHIN 8 FEET OF TOP OF SLOPE) 18" FOOTING / 8' SETBACK TOTAL DEPTH OF FOOTING 1.5:1.0 SLOPE # 2.0:1.0 SLOPE O W W a U_ o W Ln U u. z p a o N 0' 82" 66" 2' 66" 54" 4' 51" 42" 6' 34" 30" 8' 1811 1811 9 when applicable FIGURE NUMBER IV JOB NUMBER 00-7780 TOTAL DEPTH OF FOOTING MEASURED I FROM FINISH SOIL SUB-GRADE MUV •v UU REPORT OF PRELIMINARY GEOTECHNICAL AND GEOLOGIC INVESTIGATION Creighton Residence Remodel and Additions 2902 Lone Jack Road Encinitas, California JOB NO. 00-7780 06 July 2000 Prepared for: Mr. and Mrs. Jeff Creighton Pb- 1 GEOTECHNICAL EXPLORATION, INC. 4 '4 ~--~j SOIL & FOUNDATION ENGINEERING • GROUNDWATER ;1- HAZARDOUS MATERIALS MANAGEMENT • ENGINEERING GEOLOGY 06 July 2000 Mr. and Mrs. Jeff Creighton 2902 Lone Jack Road Encinitas, CA 92024 Job No. 00-7780 Subject: Report of Preliminary Geotechnical and Geologic Investigation Creighton Residence Remodel and Additions 2902 Lone Jack Road Encinitas, California Dear Mr. and Mrs. Creighton: In accordance with your request, Geotechnical Exploration, Inc, has performed an investigation of the geotechnical and general geologic conditions at the location of the subject site. The field work was performed on February 1, May 15 and June 8, 2000. It is our understanding that the existing residence is to be remodeled, including several new main-level additions, a second-story addition, a terraced patio area on the northern slope, and other associated improvements. The structure is to be a maximum of two stories in height and will be constructed of standard wood-frame building materials utilizing conventional foundation systems with concrete slab-on- grade floors. Where necessary, piers or deepened foundations may be used due to limited access for grading. The purpose of our investigation was to evaluate the soil conditions in the proposed building areas, recommend any necessary site preparation, assess the allowable bearing value of the on-site soils, and to provide slab and foundation design recommendations, as well as pier design criteria for the proposed structure and improvements. In addition, we have performed a geologic investigation of suspected landslide conditions. Our investigation revealed that the site is underlain, by medium dense to dense disturbed landslide materials and dense formational materials with approximately 2 to 4 feet of fill and topsoil. These near-surface natural and fill soils will not provide a stable soil base for the proposed new additions and associated improvements. As such, we recommend that either these loose fill and topsoils be removed and recompacted as part of site preparation or that the proposed additions be founded on a system of piers or deepened footings embedded into the underlying dense 7420 TRADE STREET • SAN DIEGO, CA 92121 • (858) 549-7222 • FAX: (858) 549-1604 • E-MAIL: geoteck@pocbell.net 2 formational materials. The floors shall span between the piers and connecting grade-beams if this option is chosen in lieu of grading in this building area. Our large-diameter drilling and down-hole geologic observations of May 15 and June 8, 2000, revealed the site to be underlain by Tertiary formational materials that appear to have been subjected to ancient landsliding and disturbance. The disturbed landslide materials extend to 35 feet below the ground surface in the southwest corner of the site. By projecting the near horizontal slide surface to the north, we verified the depth to competent formational materials encountered in the two borings placed on the northerly sloping hillside. Based on laboratory data and the well-documented cross-section geometry of the ancient landslide, slope stability analysis were performed and revealed that some risk for future landsliding does exist. However, the medium dense to dense condition of the landslide mass formational material does not present a significant potential for bearing soil settlement. In order to reduce the potential for lateral soil sliding and to bring the factor of safety against deep shear failure to 1.5, we have recommended that a buttress be constructed during grading of the north slope's terrace patio area. This will provide lateral stability to the proposed building pad and eliminate the need for a more costly deep shear-pin, caisson system. In our opinion, if the conclusions and recommendations presented in this report are implemented during site preparation, the site will be suited for the proposed additions and improvements. This opportunity to be of service is sincerely appreciated. Should you have any questions concerning the following report, please do not hesitate to contact us. Reference to our lob No. 00-7780 will expedite to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. Jaime A. Cerros, P.E. R.C.E. 34422/G. E. 2007 Senior Geotechnical Engineer JKH/JAC/LDR/pj L ie D. Reed, President C.E.G. 999Eexp,, 3-31-o17/R.G. 3391 ~QrESSlON o 9l~ A. CF~~o c2 w No.002007 Exp. 1301 Pv ~ )'ECN F OF CALF ,~~D 0EO1 L ESL r~ No. 999 CERTIFIED ENGINEERING GEOLOGIST ~~qTE of caUF ;L. TABLE OF CONTENTS PAGE I. SCOPE OF WORK 1 II. SITE DESCRIPTION 2 III. FIELD INVESTIGATION 3 IV. SOIL AND GENERAL GEOLOGIC DESCRIPTION 3 V. GEOLOGIC HAZARDS 5 VI GROUNDWATER 14 VII. LABORATORY TESTS AND SOIL INFORMATION 15 VIII. CONCLUSION AND RECOMMENDATIONS 17 IX. GRADING NOTES 37 X. LIMITATIONS 38 REFERENCES FIGURES Ia. Vicinity Map Ib. Plot Plan IIa-b. Geologic Map IIIa-i. Trench and Boring Logs IV. Slope Stability Cross Section V. Laboratory Test Results VI. Foundation Requirements Near Slopes VII. Buttress Fill Section APPENDICES. A. Unified Soil Classification System B. General Earthwork Specifications C. EQ Fault D. EQ Search E. Modified Mercalli Index Gptgo REPORT OF PRELIMINARY GEOTECHNICAL AND GEOLOGIC INVESTIGATION Creighton Residence Remodel and Additions 2902 Lone Jack Road Encinitas, California JOB NO. 00-7780 The following report presents the findings and recommendations of Geotechnical Exploration, Inc, for the subject project. 1. SCOPE OF WORK It is our understanding, based on communications with Mr. Jerry Blackwell and review of plans by Gordon Loud, Architect, that the existing structure will undergo a major remodel, including several new main-level additions, a second-story addition, and associated improvements. Due to the limited access for grading in the proposed building areas, it is our understanding that the new additions will utilize relatively shallow piers or deepened conventional foundations. With the above in mind, the Scope of Work is briefly outlined as follows: 1. Review existing geotechnical reports and maps pertinent to the subject project. 2. Identify and classify the surface and subsurface soils in the area of the proposed structure, in conformance with the Unified Soil Classification System (refer to Appendix A). 3. Make note of any landslides, faults or significant geologic features that may affect the development of the site. 4. Recommend site soil preparation procedures, including the construction of a buttress fill to help stabilize the existing landslide mass. pb, J Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 2 5. Recommend the allowable bearing pressures for the existing firm natural soils and properly compacted fills. 6. Evaluate the settlement potential of the existing formational soils or proposed properly compacted fills under the proposed new structural loads. 7. Recommend preliminary foundation design, including pier design criteria, and provide active and passive earth pressures to be utilized in design of any proposed retaining walls and foundation structures. II. SITE DESCRIPTION The property is known as a portion of Lot 18 (Assessor's Parcel No. 264-151-20) of Rancho Las Encinitas, according to Map No. 848, in the City of Encinitas, County of San Diego, State of California. The site, consisting of approximately 2.3 acres is located at 2902 Lone Jack Road at the east end of Via Di Felicita, in the Olivenhain area of the City of Encinitas (see Figure No. la, Location Map). The property is bordered on the north by a natural drainage channel, on the south by undeveloped residential property, on the east by a developed residential property, and on the west by undeveloped residential property and the former location of Lone Jack Road, which is now a private driveway. The existing structures on the site at the time of our investigation consisted of a single-story, single-family residence with a detached garage and another separate structure. Vegetation on the site consists primarily of native weeds and shrubbery, and several large eucalyptus and other trees. The property consists of a relatively level building pad graded into a moderately to steeply sloping, north-facing hillside with several level benches cut into the northern P*_ a Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 3 slope. Approximate elevations across the site range from a high of 220 feet above mean seal level (MSL) to a low of 170 feet MSL. Survey information concerning approximate elevations across the site was obtained from a site/survey plan prepared by San Dieguito Engineering. III. FIELD INVESTIGATION Two backhoe trenches were placed on the site (see Figure No. Ib) in areas where the new additions and improvements are to be located and where access allowed. The soils in the trenches were logged by our field representative, and samples were taken of the predominant soils throughout the field operation. Trench logs have been prepared on the basis of our observations and the results have been summarized on Figure No. III. The predominant soils have been classified in conformance with the Unified Soil Classification System (refer to Appendix A). In addition, four large-diameter borings were placed on the site to allow evaluation of suspected landslide conditions as indicated in the Open-file Report 86-15, ""Landslide Hazards in the Rancho Santa Fe Quadrangle San Diego County, California." Downhole logging was performed to a maximum depth of 64 feet from the surface. Bulk samples were taken from the auger spoils and laboratory tests were performed on those samples. IV. SOIL AND GENERAL GEOLOGIC DESCRIPTION Our investigation and review of pertinent geologic maps and reports indicate that the site is underlain by the medium dense to dense formational material of the Eocene-age Del Mar/Friars Formation (undifferentiated). The encountered soil profile generally consists of a veneer of fill soils and topsoil directly underlain by Pk' 0 Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 4 disturbed (landslide) formational material (refer to the trench and boring logs of Figure No. III). The encountered fill soil and topsoil were tested and found to have low relative compaction and a medium to high expansion potential. Artificial Fill: Most of the surface of the site is overlain by fill soils ranging from approximately 2 to 3 feet in thickness. The fills appear to have been placed during the original grading of the building pad and benching of the north slope. The fill soils consist of tan-gray and dark brown, clayey sand/sandy silt/clay with gravel clay, roots and siltstone. No documentation of observations or testing of the existing fill soils was available. Topsoil: Topsoil and slopewash was found below the fill or on the surface of the site, and consists of loose (soft to firm), dry, dark brown, sandy clay with some rock fragments, clay, and abundant roots. The topsoils are approximately 2 to 5 feet in thickness and are considered to be moderately to highly expansive. The topsoils have been previously disturbed and are unsuitable to support structural loads and compacted fill. Landslide Debris (Ols): Our exploratory borings revealed that the site is underlain by ancient landslide debris. The landslide debris consists of dark gray-green and brown, sandy silt with abundant caiiche and siltstone fragments; tan-gray and orange, silty sand; and dark gray-green and orange clayey silt which is highly fractured, with some high angle surfaces of iron oxide staining. A soft remolded clay seam exists at the contact with the underlying, undisturbed formational materials at a depth of approximately 35 feet. The basal slip plane was observed to be 1 inch thick and consisted of dark gray-brown remolded clay. This material is considered to be moderately to highly expansive. Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 5 Bedding dips in the upper 35 feet of disturbed material range from 45 to 70 degrees to the northeast. Between 30 to 35 feet (the disturbed zone base), the bedding strikes northeast-southwest and dips range from 10 to 12 degrees northwest. The basal. shear plane of the disturbed zone strikes N30 W and dips 2 to 3 degrees southwest. Del Mar/Friars Formation (Td/Tf : The entire site is underlain by the Eocene-age Del Mar/Friars Formation (undifferentiated), which consists of dark gray-green, sandy siltstone with interbeds of orange-brown, fine to coarse sands. The siltstones of the formational unit are by far the most common and typically they are moderately well-indurated. The siltstones of the Del Mar/Friars Formation may possess some moderate to high expansion characteristics. V. GEOLOGIC HAZARDS A. Faulting and Seismicity The San Diego area is part of a seismically active region of California. It is on the eastern boundary of the Southern California Continental Borderland, part of the Peninsular Ranges Geomorphic Province. This region is part of a broad tectonic boundary between the North American and Pacific Plates. The actual plate boundary is characterized by a complex system of active, major, right-lateral strike- slip faults, trending northwest/southeast. This fault system extends eastward to the San Andreas Fault (approximately 70 miles from San Diego) and westward to the San Clemente Fault (approximately 50 miles off-shore from San Diego) (Berger and Schug, 1991). During recent history, the San Diego County area has been relatively quiet seismically. No fault ruptures or major earthquakes have been experienced in 604 Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 6 historic time within the San Diego area. Since earthquakes have been recorded by instruments (since the 1930s), the San Diego area has experienced scattered seismic events with Richter magnitudes generally less than 4.0. During June 1985, a series of small earthquakes occurred beneath San Diego Bay; three of these earthquakes had recorded magnitudes of 4.0 to 4.2. In addition, the Oceanside earthquake of July 13, 1986, located approximately 26 miles offshore of the City of Oceanside, resulted in a magnitude of 5.3 (Hauksson, 1988). In California, major earthquakes can generally be correlated with movement on active faults. As defined by the California Division of Mines and Geology (Hart, E.W., 1980), an "active" fault is one that has had ground surface displacement within Holocene time (about the last 11,000 years). Additionally, faults along which major historical earthquakes have occurred (about the last 210 years in California) are also considered to be active (Association of Engineering Geologist, 1973). The California Division of Mines and Geology defines a "potentially active" fault as one that has had ground surface displacement during Quaternary time, that is, during the past 11,000 to 1.6 million years (Hart, E.W., 1980). Evaluation of earthquake risk requires that the effect of faulting on and the mass stability of a site be evaluated utilizing the Mlo seismic design event, i.e., an earthquake event on an active fault with less than a 10 percent probability of being exceeded in 50 years. Further, sites are classified by UBC 1997 Edition into "soil profile types SA through SF." Soil profile types are defined by their shear velocities where shear velocity is the speed at which shear waves move through the upper 30 meters (approximately 100 feet) of the ground. These are: Ph 0 Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 7 SA Greater than 1500 m/s SB 760 to 1500 m/s Sc 360 m/s to 760 m/s So 180 to 360 m/s SE Less than 180 m/s SF Soil requiring specific soil evaluation By utilizing an earthquake magnitude Mlo for a seismic event on an active fault, knowing the site class and ground type, a prediction of anticipated site ground acceleration, g, from these events can be estimated. The subject site has been assigned Classification "Sc." An estimation of the peak ground acceleration and the repeatable high ground acceleration (RHGA) likely to occur at the project site by the known significant local and regional faults within 100 miles of the site is included in Appendix C. Also, a listing of the known historic seismic events that have occurred within 100 miles of the site at a magnitude of 5.0 or greater since the year 1800, and the probability of exceeding the experienced ground accelerations in the future based upon the historical record, is provided in Appendix D. Both Appendix C and Appendix D are tables generated from computer programs EQFault and EQSearch by Thomas F. Blake (1989) utilizing a digitized file of late-Quaternary California faults (EQ Fault) and a file listing of recorded earthquakes (EQSearch). Estimations of site intensity are also provided in these listings as Modified Mercalli Index values. The Modified Mercalli Intensity Index is provided as Appendix E. It is our opinion that a known "active" fault presents the greatest seismic risk to the subject site during the lifetime of the proposed residence. To date, the nearest known "active" faults to the subject site are the northwest-trending Rose Canyon Fault, Coronado Bank Fault and the Elsinore Fault. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 8 Local Faults Reference to the geologic map for the area (Eisenberg, 1983) indicates that a few minor faults (potentially active) exist within 2 to 3 miles from the site (see Figure Nos. IIa-IIb). The geologic map suggests that these faults displace the Eocene-age formation in this area. No Pleistocene-age material or Holocene-age sediments are mapped in this area. No evidence of faulting was observed in our exploratory trenches or borings. Rose Canyon Fault: The Rose Canyon Fault Zone (Mount Soledad and Rose Canyon Faults), located approximately 6.2 miles southwest of the subject site, is mapped trending north-south from Oceanside to downtown San Diego, from where it appears to head southward into San Diego Bay, through Coronado and offshore. The Rose Canyon Fault Zone is considered to be a complex zone of onshore and offshore, en echelon strike slip, oblique reverse, and oblique normal faults. The Rose Canyon Fault is considered to be capable of causing a 7.5-magnitude earthquake and considered microseismica Ily active, although no significant recent earthquake is known to have occurred on the fault. Investigative work on faults (believed to be part of the Rose Canyon Fault Zone) at the Police Administration and Technical Center in downtown San Diego and at the SDG&E facility in Rose Canyon, has encountered offsets in Holocene (geologically recent) sediments. These findings have been accepted as confirmed Holocene displacement on the Rose Canyon Fault and this previously classified "potentially active" fault has now been upgraded to an "active" fault as of November 1991 (California Division of Mines and Geology --Fault Rupture Hazard Zones in California, 1994). Coronado Bank Fault: The Coronado Bank Fault is located approximately 21 miles southwest of the site. Evidence for this fault is based upon geophysical data (acoustic profiles) and the general alignment of epicenters of recorded seismic Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 9 activity (Greene, 1979). An earthquake of 5.3 magnitude, recorded July 13, 1986, is known to have been centered on the fault or within the Coronado Bank Fault Zone. Although this fault is considered active, due to the seismicity within the fault zone, it is significantly less active seismically than the Elsinore Fault (Hileman, 1973). It is postulated that the Coronado Bank Fault is capable of generating a 7.0- magnitude earthquake and is of great interest due to its close proximity to the greater San Diego metropolitan area. Elsinore Fault: The Elsinore Fault is located approximately 25 miles northeast of the site. The Elsinore Fault extends approximately 200 km (125 miles) from the Mexican border to the northern end of the Santa Ana Mountains. The Elsinore Fault zone is a 1- to 4-mile-wide, northwest-southeast-trending zone of discontinuous and en echelon faults extending through portions of Orange, Riverside, San Diego, and Imperial Counties. Individual faults within the Elsinore Fault Zone range from less than 1 mile to 16 miles in length. The trend, length and geomorphic expression of the Elsinore Fault Zone identified it as being a part of the highly active San Andreas Fault system. Like the other faults in the San Andreas system, the Elsinore Fault is a transverse fault showing predominantly right-lateral movement. According to Hart, et al. (1979), this movement averages less than 1 centimeter per year. Along most of its length, the Elsinore Fault Zone is marked by a bold topographic expression consisting of linearly aligned ridges, swales and hallows. Faulted Holocene alluvial deposits (believed to be less than 11,000 years old) found along several segments of the fault zone suggest that at least part of the zone is currently active. Although the Elsinore Fault Zone belongs to the San Andreas set of active, northwest-trending, right-slip faults in the southern California area (Crowell, 1962), it has not been the site of a major earthquake in historic time, other than a 6.0- Gr( ° J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 10 magnitude quake near the town of Elsinore in 1910 (Richter, 1958; Toppozada and Parke, 1982). However, based on length and evidence of late-Pleistocene or Holocene displacement, Greensfelder (1974) has estimated that the Elsinore Fault . Zone is reasonably capable of generating an earthquake with a magnitude as large as 7.5. Recent study and logging of exposures in trenches in Glen Ivy Marsh across the Glen Ivy North Fault (a strand of the Elsinore Fault Zone between Corona and Lake Elsinore), suggest a maximum earthquake recurrence interval of 300 years, and when combined with previous estimates of the long-term horizontal slip rate of 0.8 to 7.0 mm/year, suggest typical earthquake magnitudes of 6 to 7 (Rockwell, 1985). B. Other Geologic Hazards Ground Rupture: Ground rupture is characterized by bedrock slippage along an established fault and may result in displacement of the ground surface. For ground rupture to occur along a fault, an earthquake usually exceeds magnitude 5.0. If a 5.0-magnitude earthquake were to take place on a local fault, an estimated surface- rupture length 1 mile long could be expected (Greensfelder, 1974). Our investigation indicates that the subject site is not directly on a known fault trace and, therefore, the risk of ground rupture is remote. Ground Shaking: Structural damage caused by seismically induced ground shaking is a detrimental effect directly related to faulting and earthquake activity. Ground shaking is considered to be the greatest seismic hazard in San Diego County. The intensity of ground shaking is dependent on the magnitude of the earthquake, the distance from the earthquake, and local seismic condition. Earthquakes of magnitude 5.0 Richter scale or greater are generally associated with significant damage. It is our opinion that the most serious damage to the site would be caused by a large earthquake originating on a nearby strand of the Rose Canyon Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 11 Fault Zone. Although the chance of such an event is remote, it could occur within the useful life of the structure. The anticipated ground accelerations at the site from earthquakes on faults within 100 miles of the site are provided in Appendix C. Landslides: The Open-file Report 86-15 did not indicate the presence of a landslide on the site. However, based on past work experience in this area, and as shown on the County of San Diego Landslide Hazards Map, the site is located within a high- risk geologic hazard zone due to the high susceptibility for ancient landslides within the formational materials in the vicinity of the site. In addition, we understand that extensive shallow slope failures occurred on the hillsides above and below the existing residence during heavy rains in 1979-80. Review of aerial photographs indicate that the slope failures most likely occurred after January 27, 1979, and some remedial grading had occurred prior to January 1980. Placement of large-diameter borings and downhole logging by our Engineering Geologists confirmed the site to be underlain between the ground, surface and to at least 35 feet in depth, by the disturbed Del Mar/Friars Formation (ancient landslide materials). The bedding, in general, strikes to the northwest-southeast direction, and dips at inclinations ranging from 45 to 70 degrees to the northeast. The material consists of interbedded siltstones and claystones, with a 2-foot-thick sand bed between 15 and 17 feet in depth in the lower borings, and 6- to 8-foot- thick sand beds between 28 and 36 feet in depth in the upper borings. Although the material appears disturbed at several horizons, with discontinuous bedding and mixed material types, no well-defined shear planes or remolded slip plane materials were identified in the upper 35 feet. At a depth of 35 feet in boring B-4, a 1-inch- thick basal shear zone was encountered, with a continuous clay seam striking N30 W and dipping 2 to 3 degrees southwest. The entire slide mass is assumed to be dipping to the north. Orr( PW_ ° J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 12 Beginning at 35 to 36 feet in depth in boring B-4, the undisturbed formational material becomes very orange, iron-oxide stained and well cemented. At 42 feet in depth, the Del Mar/Friars Formation consists of more massive siltstone/claystone, which is well indurated with some concretionary sandstone boulders. Based on the medium dense to dense nature of formational material within the landslide mass, we do not believe the upper 35 feet of material presents a settlement hazard. However, the upper 2 to 5 feet of fill and topsoil should be removed and recompacted at least in the areas of new construction. Based on the large-diameter borings placed at this site, we have been able to prepare a cross-section of the landslide condition (see Figure No. IV). The cross- section has been used to perform an analysis of the existing landslide mass stability. Landslide Stability Analysis: The 1-inch-thick remolded clay seam at 35 feet in depth was the lowest strength material encountered in our 64-foot-deep boring in boring B-4. We did not observe the remolded clay seam in the other three borings. However, based on the depth to competent formational materials, we have projected the slip plane to the north on our cross section. Based on our laboratory data and previous experience with these material types, our geotechnical engineer has assigned an angle of internal friction of 3 degrees and a cohesion of 170 psf for the slide plane material, and an angle of internal of friction of 26 degrees and a cohesion of 475 psf for the proposed buttress material as representative of the on- site material's strength characteristics. These values have been utilized in slope stability analysis along the most critical site cross-section, A-A', as shown on Figure Nos. Ib and IV. From the cross section studied, we determined that factors of safety lower than 1.0 can be obtained with a soil has a friction angle of 3 degrees GI J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 13 and cohesion equal to or less than 170 psf. Stabilization of the soil mass is therefore required. The existing slope is considered to be potentially unstable, and possesses a factor of safety lower than 1.5 in its present condition. The recommended grading operation and proposed stabilizing improvements are expected to significantly increase the stability of the slope and reduce the potential of deep shear failure of the slope. Slope stability analysis was performed utilizing a computer program, "GSLOPE," which analyzes the factor of safety against shear stresses. In this case, a specified deep failure surface was analyzed with different soil shear strength values. With the shear strength values indicated above for the proposed buttress, the factor of safety is 1.509. The specified surface location was assumed based on boring log information and information from upslope properties. The minimum acceptable factor of safety against soil shear deep failure is 1.5. Alternative buttress material can have a higher friction angle and lower cohesion and still achieve the same desirable stability results. For instance, soil with a friction angle of 36 degrees and cohesion equal to 200 psf can be used as an alternative in the buttress area. Other combinations of friction angle and cohesion may also be adequate but would have to be evaluated on a material-specific basis. Liquefaction: The liquefaction of saturated sands during earthquakes can be a major cause of damage to buildings. Liquefaction is the process in which soils are transformed into a viscous fluid that will flow as a liquid when unconfined. It occurs principally in loose, saturated sands and silts when they are sufficiently shaken by an earthquake. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 14 On this site, the risk of liquefaction of foundation material due to seismic shaking is considered to be remote due to the relatively dense nature of the natural-ground material and the lack of a shallow static water table under the site. Summary: It is our opinion, based upon a review of the available maps, aerial photographs, and our geologic investigation, that the site is underlain by relatively unstable (against sliding) formational materials that have undergone extensive movement during previous ancient landsliding. The landslide materials appear highly fractured and disturbed, and a weak planar surface (slide plane) was encountered at a depth of 35 feet in boring B-4. We have recommended that a buttress be constructed on the slope to reduce the potential for future landslide activation and to bring the factor of safety against deep shear failure to at least 1.5. The owner should also understand that there is some risk associated with any construction in the San Diego County area due to the proximity of the Rose Canyon Fault, which is considered "active". A structural engineer should be asked to review the ground acceleration possible at the site from the Rose Canyon Fault (see Appendix C). The maximum probable repeatable ground acceleration anticipated is RHGA=0.118g. Based upon the owner's level of risk acceptance and cost concerns, the structural engineer can provide a number of structural alternatives to help improve the stability of the structure against seismic-related damage. VI. GROUNDWATER Groundwater was encountered at depths of 30 to 36 feet in two of our exploratory borings. However, we do not anticipate any significant groundwater problems to develop in the future. if the property is developed as proposed and proper drainage is maintained. J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 15 It should also be kept in mind that any required grading operations may change surface drainage patterns and/or reduce permeabilities due to the densification of compacted soils. Such changes of surface and subsurface hydrologic conditions, plus irrigation of landscaping or significant increases in rainfall, may result in the appearance of surface or near-surface water at locations where none existed previously. The damage from such water is expected to be localized and cosmetic in nature, if good positive drainage is implemented, as recommended in this report, during and at the completion of construction. Subsurface drainage with a properly designed and constructed french drain system will be required along with continuous back drainage behind basement walls, property line retaining walls, or any perimeter stem walls for raised-wood floor areas where the outside grades are higher than the crawl space grades. Furthermore, crawl spaces shall be provided with the proper cross-ventilation to help reduce the potential for moisture-related problems. It must be understood, however, that unless discovered during initial site exploration or encountered during site grading operations, it is extremely difficult to predict if or where perched or true groundwater conditions may appear in the future. When site fill or formational soils are fine-grained and of low permeability, water problems-may not become apparent for extended periods of time. The recommended buttress shall be provided with chimney drains in the back cut slope, a subdrain in the bottom of the key at the heel of the slope, and an outlet subdrain to the north (see schematic cross sections). Water conditions, where suspected or encountered during grading operations, should be evaluated and remedied by the project civil and geotechnical consultants. The project developer and eventual homeowners, however, must realize that post- J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 16 construction appearances of groundwater may have to be dealt with on a site- specific basis. VII. LABORATORY TESTS AND SOIL INFORMATION Laboratory tests were performed on the disturbed and relatively undisturbed soil samples in order to evaluate their physical and mechanical properties and their ability to support the proposed additions and improvements. The following tests were conducted on the sampled soils: 1. Moisture Content (ASTM D2216-92) 2. Moisture/Density Relations (ASTM D1557-91, Method A) 3. Density Measurement (ASTM D1188-92) 4. Expansion Test (UBC Test Method 29-2) 5. Direct Shear Test (ASTM D3080-90) The moisture content of a soil sample is a measure of the weight of water, expressed as a percentage of the dry weight of the sample. The relationship between the moisture and density of soil samples gives qualitative information regarding the soil strength characteristics and compaction soil conditions to be anticipated during any future grading operation. The expansion potential of the tested on-site soils was determined utilizing the Uniform Building Code Test Method for Expansive Soils (UBC Standard No. 29-2). In accordance with the UBC (Table 18-1-B), expansive soils are classified as follows: Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 17 Expansion Index Potential Expansion 0 to 20 Very low 21 to 50 Low 51 to 90 Medium 91 to 130 High Above 130 Very high According to the UBC Test Method for Expansive Soils, the sampled soils on the site have a medium to high expansion potential, with a maximum tested expansion index of 93 (high expansion potential). Direct shear tests were performed on remolded samples in order to evaluate the soils strength characteristics and support capacity of the existing landslide debris and proposed fill soils. The shear tests were performed with a constant strain rate direct shear machine. The specimens tested were saturated and then sheared under various normal loads under drained conditions at a slow rate. Based on laboratory test data, our observations of the primary soil types on the project, and our previous experience with laboratory testing of similar soils, our Geotechnical Engineer has assigned conservative values for friction angle, coefficient of friction, and cohesion for those soils which will have significant lateral support or bearing functions on the project. The assigned values are presented in Figure No. V and have been utilized in the determining the recommended bearing value as well as active and passive earth pressure design criteria. VIII. CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based upon the practical field investigation conducted by our firm, and resulting laboratory tests, in conjunction Ph. a J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 18 with our knowledge and experience with the soils in the Olivenhain area of the City of Encinitas. Our geologic investigation revealed that ancient landslide materials underlie the property to a depth of at least 35 feet. Due to the geometry of the slide mass and our stability analysis, we have recommended that a buttress be constructed on the northern slope of the property to reduce the potential for future landslide activation. Our investigation revealed the disturbed upper 35 feet of formational material to be in a medium dense to dense condition. We do not believe the materials pose a significant settlement hazard. Some loose fill soil and topsoil exist in the proposed building areas. In their present condition, the fill soil and topsoil will not provide a stable soil base for the proposed new structure and improvements. As such, we recommend the loose soils be removed and recompacted as part of site preparation in the new construction areas. In addition, slope face soils south of the proposed buttress shall also be removed and recompacted. Field observations during grading will determine the depth of removal needed. The proposed buttress will be placed on the northern slope as shown on Figure No. Ib. The approximate dimensions are 180 feet long by 115 feet wide, extending south from the northern property boundary into the north-facing slope. The maximum vertical depth of excavation will be approximately 20 feet along the southern perimeter of the buttress, and approximately 5 feet along the northern perimeter. A temporary cut of 1.5:1.0 (horizontal to vertical) is required in the back of the cut. GH Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 19 The existing fill, topsoils and disturbed formational materials should be removed to a depth of at least 5 feet below the slide plane elevation. These materials should be evaluated by a representative of our firm during the excavation process. The select or higher-quality materials should be stockpiled for use as recompacted fill within the buttress area. Some mixing of the existing sands and clay soils may be required to achieve the required soil values of the buttress fill materials. Additional laboratory tests will determine whether or not the mix of on-site soils will provide the minimum soil strength values for use in the buttress area. If not, import soils shall be brought to the site for buttress construction. A. Buttress Construction and Preparation of Soils for Site Development 1. The existing improvements, debris and vegetation observed on the building site should be removed prior to the preparation of the building pad and/or areas to receive rigid improvements. 2. In order to provide a uniform, firm soils base for the proposed new additions and improvements, the existing loose fill soil and topsoils located in the proposed building area and extending for a lateral distance equal to the depth of the loose soil, but not less than 5 feet beyond the perimeter thereof (where possible), shall be excavated to expose firm, native soil, or as per the indication of our field representative. This depth is expected to be approxi- mately 2 to 4 feet in the building areas (see Figure No. II for depth of fill and topsoil). Any areas exposing very fractured soils will require removal and recompaction. Once the cuts are made, a representative of our firm will indicate to the grading contractor what areas need to be further excavated for soil recompaction. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 20 3. Based on the results of our analysis, we recommend that the site be stabilized by a buttress fill. 3.1 The buttress fill shall consist of on-site reworked material (removed and recompacted) to the approximate dimensions shown on the cross sections. It is recommended that the buttress grading operation be performed during the dry season (May through November, inclusive). As indicated previously, the mix of on-site soils shall meet the minimum strength values previously indicated to be used as buttress fill. 3.2 The buttress fill shall be provided with one subdrain at the heel of the key excavation and with chimney drains in the back of the temporary cut slope. The subdrain shall drain to the north, with a minimum uniform slope of 1.0 percent. The subdrain shall consist of rigid perforated pipe place in an envelope of gravel and filtercloth such as 140N Mirafi (see Figure No. VII). The chimney drains shall consist of sheets of J-Drain 102 with edge spaces up to 4 feet (maximum). 3.3 The north end of the subdrain shall discharge into an approved drainage facility. 3.4 The subdrain pipe shall consist of perforated PVC pipe, type ABS or SDR 23.5 or PVC Schedule 40. The pipe shall be not less than 4 inches in diameter and shall be placed with the holes facing down, at least 6 inches from the bottom and sides of a triangular shape envelope of gravel (1 inch maximum size), wrapped with filter fabric, manufactured non-woven, polypropylene, with mullen burst strength of at least 140 psi and puncture strength of at least 45 psi. The ends of the filter 64 Ph. ° J Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 21 cloth shall overlap at the trench top at least 6 inches. The collector subdrain placed in the middle of the buttress shall be placed in a trench at least 11/2 feet deep and be built in an envelope of gravel and filter cloth as indicated for the back subdrain. The perforated subdrain shall transition into an unperforated pipe 15 feet before it daylights out (see cross section). 3.5 A geologist and/or a soils engineer shall visit the site periodically to observe the progress of the cut and to provide additional recommendations if warranted. The excavation shall be evaluated and approved by our geologist and/or soils engineer prior to backfilling. Also, the cut shall be made in at least two halves, rather than one large excavation. 3.6 All fill soils shall be compacted under the observations and testing of a representative of our firm. The fill shall be compacted to at least 92 percent of Maximum Dry Density (determined by ASTM D1557). All grading shall be performed in accordance with the City of Encinitas Grading Ordinance, the recommendations of this report, the specifications in Appendix B of this report, and any addenda provided by -our firm. It is our preliminary opinion that all of the anticipated cut soils can be used as fill. Any material larger than 6 inches shall be broken into smaller pieces or excluded from the fill mass. 3.7 It is recommended that our firm review the construction plans and project specifications prior to any stabilization work on the slope. Also, we recommend that a pre-construction 'meeting be held at the site J Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 22 with the owner/developer, civil engineer, contractor, and geotechnical engineer in attendance. Special soil handling procedures and the grading plan requirements can be discussed at that time. 3.8 Those areas supporting proposed retaining structures or other improvements (such as the patios, drives, walkways, decks and swimming pools) should be prepared in a like manner. Hillside grading shall be performed as per our General Earthworks Specifications, Appendix B. Final grading and foundation recommendations will be provided after the final project plans are reviewed by our firm. 4. No uncontrolled fill soils shall remain on the site after completion of any future site work. In the event that temporary ramps or pads are constructed of uncontrolled fill soils, the loose fill soils shall be removed and/or recompacted prior to completion of the grading operation. 5. Any buried objects or abandoned utility lines, etc., which might be discovered in the construction areas, shall be removed and the excavation properly backfilled with approved on-site or imported fill soils and compacted to at least 90 percent of Maximum Dry Density. Any encountered medium or highly expansive soils in building pad areas shall be compacted to between 88 and 92 percent of Maximum Dry Density, at a moisture content at least 5 percent over optimum. 6. Any backfill soils placed in utility trenches or behind retaining walls that support structures and other improvements (such as patios, sidewalks, driveways, pavements, etc.) shall be compacted similarly. To reduce lateral Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 23 soil pressure on the retaining walls, the on-site clayey soils should be removed and replaced with imported, low-expansive soils in the active wedge backfill area behind those retaining walls. The backfill soils shall have an expansion index less than 50. Project plans shall also specify the same requirements for retaining wall backfill soils. B. Design Parameters for Shallow Foundations 7. The recommended allowable soil bearing value for design of shallow foundations for the proposed additions is 2,000 pounds per square foot for properly compacted fill and 3,000 pounds per square foot for dense formation. These load-bearing values may be utilized in the design of continuous foundations and spread footings when founded a minimum of 18 inches into the firm natural ground or properly compacted fill, measured from the lowest adjacent grade at the time of foundation construction. These load-bearing values may be increased one-third for structural analysis that include wind or seismic loads. The soil bearing capacity may be increased for extra depth and width (800 psf and 400 psf, respectively) to a maximum 4,000 psf. 8. The passive earth pressure of the encountered natural-ground soils and any properly compacted fill soils (to be used for design of shallow foundation and footings to resist the lateral forces) shall be based on an Equivalent Fluid Weight of 250 pounds per cubic foot for fill soils and 300 pcf for formational soils. This passive earth pressure shall only be considered valid for design if the ground adjacent to the foundations structure is essentially level for a distance of at least three times the total depth of the foundation. 614 rb, a J Creighton Residence Remodel. & Additions Job No. 00-7780 Encinitas, California Page 24 9. A Coefficient of Friction of 0.35 times the dead load may be used between the bearing soils and concrete wall foundations or structure foundations and floor slabs. 10. The following table summarizes site-specific seismic design criteria for the calculation of seismic base shear. The desian criteria was obtained from the Uniform Building Code (1997 edition) based on the closest active fault location, soil type, and soil conditions. Parameter Value Reference Seismic Zone Factor Z 0.40 Table 16-I Soil Profile Type Sc Table 16-3 Seismic Coefficient, Ca 0.40Na Table 16- Seismic Coefficient, C„ 0.56N„ Table 16-R Near-Source Factor Na 1.0 Table 16-S Near-Source Factor, N„ 1.0 Table 16-T Seismic Source Type B Table 16-U 11. Our experience indicates that, for various reasons, footings and slabs occasionally crack, causing ceramic tiles and brittle surfaces to become damaged. Therefore, we recommend that all conventional shallow footings and slabs-on-grade contain at least a minimum amount of reinforcing steel to reduce the separation of cracks, should they occur. 11.1 A minimum of steel for continuous footings should include at least four No. 5 steel bars continuous, with two bars near the bottom of the footing and two bars near the top. Ph, 0 J Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 25 11.2 Isolated square footings should contain, as a minimum, a grid of three No. 4 steel bars on 12-inch centers, both ways, with no less than three bars each way. 11.3 Interior floor slabs on-grade (on properly compacted soils) should be a minimum of 5 inches actual thickness and be reinforced with at least No. 3 bars on 18-inch centers, both ways, placed at midheight in the slab. Slabs shall be underlain by a 2-inch-thick layer of clean sand (S.E. = 30 or greater) overlying a reinforced vapor barrier over 2 inches of sand (including the middle height). For basement-type slabs, a heavier membrane (such as 20-mil Paraseal or PMPC) and a 4- inch-thick base layer below the membrane is recommended. Slab subgrade soil shall be verified to have the proper moisture content (at least 5 percent above optimum to 12 inches below subgrade if soils are medium to highly expansive) within 48 hours prior to placement of the vapor barrier and pouring of concrete. The membrane layer shall have at least 6-inch-wide overlaps and be sealed per the manufacturer's instruction. The project architect shall discuss with the owner the degree of moisture risk and the types of protection that are available for the basement-type slabs on grade. Water stops are also recommended-at joints of walls and slabs. We recommend the project Civil/Structural Engineer incorporate isolation joints and sawcuts to at least one-fourth the thickness of the slab in any floor designs unless reinforced for a jointless slab condition. The joints and cuts, if properly placed, should reduce the potential for and help control floor slab cracking. It is recommended that shrinkage joints be placed no farther than 20 feet, approximately. However, due to a number of reasons (such as base preparation, construction techniques, curing procedures, and normal 64 Ph, 0 Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 26 shrinkage of concrete), some cracking of slabs can be expected. Control joints may be waived in structural slabs. NOTE: The project Civil/Structural Engineer shall review all reinforcing schedules. The reinforcing minimums recommended herein are not to be construed as structural designs, but merely as minimum safeguards to reduce possible crack separations. Based on our laboratory test results and our experience with the soil types on the subject site, the dense natural soils and properly compacted fill soils should experience differential angular rotation of approximately 1/240 or less under the recommended allowable loads. The maximum differential settlement across the structure when founded on properly compacted fill or dense natural formation should be on the order of 1 inch. To allow for post- construction differential settlement evaluations, we suggest performance of a relative elevation survey within 30 days of pouring concrete slabs and foundations or laying raised wood floors. 12. As a minimum for protection of on-site improvements, it is recommended that all nonstructural concrete slabs (such as patios, sidewalks, etc.), be founded on properly moisture-conditioned and compacted and tested fill or dense native formation and underlain by a leveling course of 3 inches of clean sand, with 6x6-6/6 welded wire mesh at the center of the slab, and contain adequate isolation and control joints. Joints shall be spaced no farther than 15 feet apart and at re-entrant corners. Driveways shall be Diaced on properly compacted subgrade and/or base material. The performance of on- site improvements can be greatly affected by soil base preparation and the quality of construction. It is therefore important that all improvements are properly designed and constructed for the assumed soil conditions. The Oki Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 27 improvements should not be built on loose soils or fills placed without our observations and testing. Any rigid improvements founded on the existing loose surface soils and/or expansive soils can be expected to undergo movement and possible damage and is therefore not recommended. Geotechnical Exploration, Inc. takes no responsibility for the performance of the improvements. 13. Exterior slabs on-grade built on the on-site, moderately (EI 90 or less) expansive soils shall be provided with a thickened edge penetrating at least 8 inches into the ground and reinforced with at least one No. 4 steel bar. The subgrade soils for any rigid improvement shall be moisture conditioned to at least 5 percent above the optimum and be compacted as described in Recommendation #5 of this report. 14. Concrete driveway slabs shall be at least 5 inches thick and rest on properly prepared and compacted subgrade soils. The slab shall be made of concrete at least Fc = 3,500 psi. Control joints shall be placed no farther than 15 feet apart (or the width of the slab) and also at re-entrant corners. Asphalt- paved driveways shall consist of at least 3 inches of asphalt concrete on 8 inches of Class II base material. 15. Soil moisture verification and compaction of areas to receive rigid exterior improvements shall be made by our representative within 48 hours prior to concrete placement. Control and isolation joints in exterior slabs shall be sealed with elastomeric joint sealant. The sealant shall be inspected by the owner every 6 months and be properly maintained T~~ Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 28 C. Design Parameters for Pier Supports Due to the limited access at the location of the proposed additions, it is anticipated that the use of piers may be required in lieu of soil removal and recompaction. The following recommendations should be followed for pier supports beneath areas with additional structural loading. We encountered between 2 to 4 feet of loose to medium dense fill and topsoil over medium dense formational terrace material in the area of the proposed additions. 16. Where piers are utilized, they shall be designed by the project Civil/Structural Engineer to support all vertical and lateral loads of the proposed additions. The floors shall be suspended and supported by grade-beams transmitting the loads to the piers. 17. For vertical loading, all piers should be embedded at least 2 feet into dense terrace materials, to be approved upon observation by a representative of this firm. For lateral loading design, the pier length may require additional embedment. It is important, when excavating for piers that utilize end- bearing strength, to limit the amount of loose material on the bottom of the excavation. Therefore, we recommend that the piers be designed with a minimum diameter or width of 24 inches in order to facilitate observation of the excavations and allow for easy removal of material on the bottom. For end-bearing capacity piers, no slough over 1 inch in thickness shall remain at the bottom of the excavation before concrete placement. It should be noted that the rocky soils and formational materials could make pier excavation difficult. The contractor should bid the project with this in mind. Shoring protection shall be installed if hand labor is used to remove soils or rocks in the excavation. Sri rk. a r Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 29 18. The minimum center-to-center spacing of piers, in a direction perpendicular to the lateral load, shall be 3 pier diameters. For piers located in the same line of the applied lateral load, the shadow effect produces a reducing effect in their combined individual lateral load capacity. For 24-inch-diameter piers spaced 10 feet center-to-center, the reduction factor shall be equal to 2.2, for the sum of the individual capacities. If the spacing is 12 feet center-to- center, the reduction factor is 1.8. The reduction factor for piers spaced at least 16 feet apart is 1.0. 19. The allowable end bearing capacity is 4,000 pounds per square foot (psf) for piers penetrating at least 2 feet into dense terrace soils. This end-bearing capacity has already deducted the down drag force produced by existing fills. The pier weight to be considered is only one-third of the actual weight of buried pier. The actual needed pier length and embedment into formational soils shall be established by the structural engineer based on the length needed to adequately support the total vertical and lateral loads included in the design. An increase of 900 psf in vertical end-bearing capacity may be allowed for every additional foot of pier embedment into formational soil. The maximum end-bearing capacity is 25,000 psf. 20. For lateral earthquake or wind load resistance, the structural engineer may use any method that considers the equilibrium of forces and moments. Some structural engineers like to use the fixity concept. Based on a free- head pier with diameter equal to 24 inches, the concrete modulus of elasticity, and a horizontal sub-grade reaction of the loose fills, we recommend that fixity depth to be considered in the calculation be not less than 7 feet for free-head piers and 15 feet from the soil surface for fixed- head piers. For free-head piers, the maximum moment shall be calculated by multiplying the lateral force times one-half the fixity depth, plus the distance Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 30 to the application of lateral load. For fixed-head piers, the maximum moment shall be calculated by multiplying the lateral load times one-half the fixity depth. If a balance of forces is calculated based on the applied lateral forces and reaction soil forces, the following allowable passive (equivalent fluid) forces are recommended: for existing fill soils 130 pcf and for formational soils 300 pcf. The passive resistance of the piers may be considered applicable on a projected surface equal to 2.5 times the diameter of the pier multiplied by the vertical length being considered. 21. Another option chosen by some engineers is the use of the pole equation presented in UBC Section 1806.8.2. to calculate minimum depth of embedment of the piers due to lateral loads. The maximum lateral bearing of fill soil is 1,950 psf; 8,000 psf for formational soils. 22. Piers embedded into the underlying dense formation a minimum of 2 feet may be designed utilizing an allowable soil end-bearing value or 4,000 pounds per square foot (psf). The end-bearing capacity may be increased an additional 900 psf for every additional one foot of embedment into formational soil, to a maximum of 25,000 psf. End-bearing piers or combined end-bearing and friction piers shall have the toe of the pier hand- tool cleaned to remove any loose material. An allowable average frictional resistance of 175 psf may be added only to the pier portion embedded into formational soil. The recommended allowable end bearing vertical capacity for the piers already includes the effect of negative friction produced by the existing fills as well as the buried pier weight. Any pier weight above the soil surface shall Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 31 be considered as dead load and shall be deducted from the net end-bearing capacity (for the buried portion only, consider the net pier weight equal to 30 pcf). The depth to dense formational soils in the explored area was encountered to range from approximately 2 to 4 feet from the existing level pad surface. 23. Pier digging operations shall be performed under the intermittent observations of a representative of our firm to confirm the penetration into formational soils. 24. The design and construction of the piers shall be in accordance with the recommendations presented above, the current UBC requirements accepted by the City of Encinitas, and also in accordance with ACI 336, 311-93 Design and Construction of Drilled Piers, of the American Concrete Institute. The contractor shall follow all the safety procedures required by Cal OSHA. 25. It is also our recommendation that the pier excavations be filled with concrete within 2 days after the excavations are completed, to help reduce the risk of soil caving, mud or slough intrusion, etc. D. Retaining Walls 26. The active earth pressure (to be utilized in the design of any cantilever retaining walls, utilizing imported very low-expansive to low-expansive soils [EI less than 50] as backfill) shall be based on an Equivalent Fluid Weight of 38 pounds per cubic foot (for level backfill only). In the event that a retaining wall is surcharged by sloping backfill, the design active earth pressure shall be based on the appropriate Equivalent Fluid Weight presented in the following table. Retaining wall plans shall specify that all retaining wall 64 0 W,WEr~ Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 32 backfill shall consist of imported, very low-expansive to low-expansive soils (EI less than 50). In the event that a retaining wall is to be designed for a restrained condition, a uniform pressure equal to 9xH (nine times the total height of retained soil, considered in pounds per square foot) shall be considered as acting everywhere on the back of the wall in addition to the design Equivalent Fluid Weight. The soil pressure produced by any footings, improvements, or any other surcharge placed within a horizontal distance equal to the height of the retaining portion of the wall shall be included in the wall design pressure. The recommended lateral soil pressures are based on the assumption that no loose soils or soil wedges will be retained by the retaining wall. Backfill soils shall consist of imported low expansive soils with EI less than 50, and should be placed from the heel of the foundation to the ground surface within the wedge formed by a plane at 300 with the vertical and passing by the heel of the foundation and the back of the wall. Any loads placed on the active wedge behind a cantilever wall shall be included in the design by multiplying the load weight by a factor of 0.32. For a restrained wall, the lateral factor shall be 0.52. Gr( 0 *To determine design active earth pressures for ratios intermediate to those presented, interpolate between the stated values. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 33 E. S/open 27. The soils that occur within 8 feet of the face of any slopes often possess poor lateral stability and structures and other improvements could suffer differential movement as a result of the poor lateral stability of these soils. Furthermore, foundations built on loose soils have potential for drifting both laterally and vertically. Shallow footings of proposed structures, walls, fences, swimming pools, etc., when founded 8 feet and farther away from the top of slopes on properly compacted soils, may be of standard design in conformance with the recommended load-bearing value. If the proposed foundations and footings are located closer than 8 feet inside the top of slopes, they shall be deepened to 11/2 feet below a line beginning at a point 8 feet horizontally inside the slopes and projected outward and downward, parallel to the face of the slope and into firm soils (see Figure No. VI). 28. We anticipate that other temporary slopes into the existing soils and formational material of up to approximately 20 feet in height may be required during construction of the buttress fill area. Based on the results of our field investigation, it is our opinion that the following temporary-slope design criteria may be considered in areas where the excavation slope top will be at least 10 feet away from any existing structures and bottom cuts are made into formational soils. The temporary cuts for the buttress shall be made at a slope ratio equal to 1.5:1.0 (horizontal to vertical), in the southern end, for cuts up to 10 feet in height. For shorter cuts, a 1.0:1.0 ratio may be used. Ph, 0 Creighton Residence Remodel & Additions Encinitas, California 29. Job No. 00-7780 Page 34 As indicated previously, the buttress excavation in the southern end shall be performed in not less than two halves to prevent triggering a slope failure. Any plans for slopes in excess of the anticipated 20-foot maximum must be presented to our office prior to grading to allow time for review and specific recommendations, if warranted. Proper drainage away from the excavation shall be provided at all times. Soil stockpiles shall not be placed within 10 feet from the top of the cuts. A representative of Geotechnical Exploration, Inc. must observe any steep temporary slopes during construction. In the event that soils and formational material comprising a slope are not as anticipated, any required slope design changes would be presented at that time. Where not superseded by specific recommendations presented in this report, trenches, excavations and temporary slopes at the subject site shall be constructed in accordance with Title 8, Construction Safety Orders, issued by OSHA. It is our opinion that the proposed development should not significantly affect the existing slopes on the subject site. However, regular observations and adequate maintenance must be provided to the slopes so that any erosion problem is promptly corrected. The existing steep slope in the southern portion of the site consists of artificial fill soils that will be completely removed during the excavation of the lower-level living area. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 35 F. Site Drainage Considerations 30. Adequate measures shall be taken to properly finish-grade the building site after the additions and other improvements are in place. Drainage waters from this site and adjacent properties are to be directed away from the foundations, floor slabs, footings, and slopes, onto the natural drainage direction for this area or into properly designed and approved drainage facilities. Roof gutters and downspouts should be installed on the structure, with the runoff directed away from the foundations via closed drainage lines. Proper subsurface and surface drainage will help minimize the potential for waters to seek the level of the bearing soils under the foundations, footings and floor slabs or further erosion of the adjacent natural slope. Failure to observe this recommendation could result in undermining and possible differential settlement of the structure or other improvements on the site. In addition, appropriate erosion control measures shall be taken at all times during construction to prevent surface runoff waters from entering footing excavations, ponding on finished building pad areas or running over the existing cut slopes. 31. Due to possible buildup of groundwater (derived primarily from rainfall and irrigation), excess moisture is a common problem in below-grade structures or behind retaining walls that may be proposed. These problems are generally in the form of water seepage through walls, mineral staining, mold growth and high humidity. Even without the presence of free water, the capillary draw characteristics, especially of fine grained soils, can result in excessive transmission of water vapor through walls and floor slabs. In order to minimize the potential for Ph, a Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 36 moisture-related problems to develop at the site, proper interior and crawlspace ventilation shall be provided, and proper waterproofing and subsurface drainage shall be provided for building retaining walls and slabs of below-ground areas. 32. Proper subdrains and free-draining backwall material or geofabric drainage shall be installed behind all retaining walls (in addition to proper waterproofing) on the subject project. Geotechnical Exploration, Inc. will assume no liability for damage to structures or improvements that is attributable to poor drainage. The architectural plans shall clearly indicate that the bottom of exterior subdrain pipes are at least 11/2 feet below the interior slab subgrade (see Figure No. VII). 33. Planter areas, flower beds, and planter boxes shall be sloped to drain away from the foundations, footings, and floor slabs at a gradient of at least 5 percent within 5 feet from the wall. Planter boxes shall be constructed with a closed bottom and a subsurface drain, installed in gravel, with the direction of subsurface and surface flow away from the slopes, foundations, footings, and floor slabs, to an adequate drainage facility. The planter boxes shall have all walls and bottoms properly waterproofed and sealed. G. General Recommendations 34. Following placement of any concrete floor slabs, sufficient drying time must be allowed prior to placement of floor coverings. Premature placement of floor coverings may result in degration of adhesive materials and loosening of the finish floor materials. Ph, Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 37 35. In order to minimize any work delays at the subject site during site development, this firm should be contacted 24 hours prior to any need for observation of footing excavations or field density testing of compacted fill soils. If possible, placement of formwork and steel reinforcement in footing excavations should not occur prior to observing the excavations; in the event that our observations reveal the need for deepening or redesigning foundation structures at any locations, any formwork or steel reinforcement in the affected footing excavation areas would have to be removed prior to correction of the observed problem (i.e., deepening the footing excavation, recompacting soil in the bottom of the excavation, etc.) IX. GRADING NOTES Any required grading operations shall be performed in accordance with the General Earthwork Specifications (Appendix B) and the requirements of the City of Encinitas Grading Ordinance. 36. Geotechnical Exploration, Inc. recommends that we be asked to verify the actual soil conditions revealed during site grading work and footing excavation to be as anticipated in the "Report of Preliminary Geotechnical and Geologic Investigation" for the project. In addition, the compaction of any fill soils placed during site grading work must be tested by a soil engineer. It is the responsibility of the grading contractor to comply with the requirements on the grading plans and the local grading ordinance. All retaining wall and trench backfill that will support structures or rigid improvements shall be properly compacted. Geotechnical Exploration, Inc. will assume no liability for damage occurring due to improperly or uncompacted backfill placed without our observations and testing. Creighton Residence Remodel & Additions Encinitas, California Job No. 00-7780 Page 38 37. It is the responsibility of the owner and/or developer to ensure that the recommendations summarized in this report are carried out in the field operations and that our recommendations for design of this project are incorporated in the project plans. We shall be provided with the opportunity to review the project plans once they are available, to see that our recommendations are adequately incorporated in the plans. After reviewing the plans, additional or modified recommendations may be issued as warranted. 38. This firm does not practice or consult in the field of safety engineering. We do not direct the contractor's operations, and we cannot be responsible for the safety of personnel other than our own on the site; the safety of others is the responsibility of the contractor. The contractor should notify the owner if he considered any of the recommended actions presented herein to be unsafe. X. LIMITATIONS Our conclusions and recommendations have been based on all available data obtained from our field investigation and laboratory analysis, as well as our experience with- the soils and formational materials located in the Olivenhain area of the City of Encinitas. Of necessity, we must assume a certain degree of continuity between exploratory excavations and/or natural exposures. It is, therefore, necessary that all observations, conclusions, and recommendations be verified at the time grading operations begin or when footing excavations are placed. In the event discrepancies are noted, additional recommendations may be issued, if required. Creighton Residence Remodel & Additions Job No. 00-7780 Encinitas, California Page 39 The work performed and recommendations presented herein are the result of an investigation and analysis that meet the contemporary standard of care in our profession within the County of San Diego. No warranty is provided. This report should be considered valid for a period of two (2) years, and is subject to review by our firm following that time. If significant modifications are made to the building plans, especially with respect to the height and location of any proposed structures, this report must be presented to us for immediate review and possible revision. The firm of Geotechnical Exploration, Inc, shall not be held responsible for changes to the physical condition of the property, such as addition of fill soils or changing drainage patterns, which occur subsequent to issuance of this report and the changes are made without our observations, testing, and approval. Once again, should any questions arise concerning this report, please feel free to contact the Project Coordinator. Reference to our Job No. 00-7780 will expedite a reply to your inquiries. Respectfully submitted, GEOTECHNICAL EXPLORATION, INC. Ja~-K. Weiser Se Zroject Geologist Jae A. Cerros, P.E. R.C.E. 34422/G. E. 2007 Senior Geotechnical Engineer L e D. Reed, President C.E.G. 999[exp. 3-31-=/R~G.~•- Qao EsS/n a~9r Ce, 0 C-D a i No. 002007 m Exp./30/U3 u' c~ Pv 0TECHNNG \Q lF ~F CA1~~F~~~ G,g D. RED No. 999 ~ * CERTIMED ENGMEERIM s, GEOLOGMT l~rEOF CA~a * Pk' a REFERENCES JOB NO. 00-7780 July 2000 Association of Engineering Geologists, 1973, Geology and Earthquake Hazards, Planners Guide to the Seismic Safety Element, Southern California Section, Association of Engineering Geologists, Special Publication, Published July 1973, p. 44. Berger & Schug, 1991, Probabilistic Evaluation of Seismic Hazard in the San Diego-Tijuana Metropolitan Region, Environmental Perils, San Diego Region, San Diego Association of Geologists. California Division of Mines and Geology - Alquist-Priolo Special Studies Zones Map, November 1, 1991. Crowell, J.C., 1962, Displacement along the San Andreas Fault, California; Geologic Society of America Special Paper 71, 61 p. Eisenberg, L., 1983, Eocene Geology, Encinitas and Rancho Santa Fe Quadrangles, San Diego County, California. Greene, H.G., 1979, Implication of Fault Patterns in the Inner California Continental Borderland between San Pedro and San Diego, in "Earthquakes and Other Perils, San Diego Region," P.L. Abbott and W.J. Elliott, editors. Greensfelder, R.W., 1974, Maximum Credible Rock Acceleration from Earthquakes in California; California Division of Mines and Geology, Map Sheet 23. Hart, E.W., D.P. Smith and R.B. Saul, 1979, Summary Report: Fault Evaluation Program, 1978 Area (Peninsular Ranges-Salton Trough Region), Calif. Div. of Mines and Geology, OFR 79-10 SF, 10. Hart E.W., 1980, Fault-Rupture Hazard Zones in California, Calif. Div. of Mines and Geology, Special Publication 42, Rev. March 1980, p. 25. Hauksson, E. and L. Jones, 1988, The July 1988 Oceanside (ML=5.3) Earthquake Sequence in the Continental Borderland, Southern California Bulletin of the Seismological Society of America, v. 78, p. 1885-1906. Hileman, J.A., C.R. Allen and J.M. Nordquist, 1973, Seismicity of the Southern California Region, January 1, 1932 to December 31, 1972; Seismological Laboratory, Cal-Tech, Pasadena, Calif. Kennedy, M.P., 1975, Geology of the San Diego Metropolitan Area, California; Bulletin 200, Calif. Div. of Mines and Geology, 1975. McEuen, R.B. and C.J. Pinckney, 1972, Seismic Risk in San Diego; Transactions of the San Diego Society of Natural History, Vol. 17, No. 4, 19 July 1972. Richter, C.G., 1958, Elementary Seismology, W.H. Freeman and Company, San Francisco, Calif. Rockwell, T.K., D.E. Millman, R.S. McElwain, and D.L. Lamar, 1985, Study of Seismic Activity by Trenching Along the Glen Ivy North Fault, Elsinore Fault Zone, Southern California: Lamar-Merifield Technical Report 85-1, U.S.G.S. Contract 14-08-0001-21376, 19 p. Toppozada, T.R. and D.L. Parke, 1982, Areas Damaged by California Earthquakes, 1900-1949; Calif. Div. of Mines and Geology, Open-file Report 82-17, Sacramento, Calif. SITE MAP Figure Number la Job Number 00-7780 0 0 U. ~ 1 LL o rr z 0A 00 0X 0 e~ W Z Z z 0 W 0 a F J OW. 0 J S J r 0 1O O J z 0 n g ~ 0 W z RO RO U Z c J J C m W v - ~a ED J L a ~ I C I a Z N I ] N x c m ~I o U- C3 pq C~ I I WWQ W rY a ¢ Z . W ¢ ° L~ s . I fY fY fl W W ►1 G N f J 1 J U W 3 U 2 ZW2 J~ N 0 Z M °QZ W t]C to I 0 ~aw J - W U Z W Q z _3 La L-j CL I :t I WN W HZ +lrflllllil fl ~ r ' W N p lr 1 1 r 1 1 r 1 Ir l,Ei;lEilEillll • ~ I _ illiltllllJTl:tfilf !f: tlllllfflll lllltill lfl 11111 111 ~ i 1111111 1 1111 1 1 1 111f11lIIIIII E II►Iltllllllllfi- N m w Co \ i d I d g 2 B E 'D ~g o Ix 0 00 zo ; goeZ ()NWU.-1 O~9 Q) 1 LL! i .S` J O O O N J o4 2 d o c v H ~ o > c `a:.~o o0aa o o $ c m y 0'U V omo I? ~or- cE0 °o* b ° c~? cyj C ou c W p 03 n ooa` 0`'>.° 0nao~ N a- E co 0 O 0 :3 Z aE om c ~C -O C,r O CL 04 Geology Map (Lenard Eisenberg 1983) ti z FIGURE No. Ila JOB No. 00-7780 Creighton Residence Additions 2902 Lone Jack Road Encinitas, CA. PLEISTOCENE AND EOCENE GEOLOGY OF THE ENCINITAS AND RANCHO SANTA FE QUADRANGLES LEGEND Qs Sweitzer Formation, with deposits on the... Qsbr Bird Rock, Qsn Nestor, Qsp Palomar, Qsm Magdalena, Qsq Quail, Qsb Bulrush, Qsmv Marview, Qsc Clairemont and Qst Tecolote marine terraces. Qsu Sweitzer Formation, terrace deposits, (undifferentiated) Qsst Sweitzer Formation, stream terrace deposits Qse Sweitzer Formation, estuarine deposits Tmv Mission Valley Formation Tat Stadium Conglomerate Tsc Scripps Formation Tt/sc Torrey Sandstone /Scripps Formation, (undifferentiated) To Ardath Shale Tt Torrey Sandstone Td/f Delmar Formation /Friars Formation, (undifferentiated) Td Delmar Formation Kp Point Loma Formation K I Lusardi Formation Ke Escondido Creek Leucogranodiorits jsp Santiago Peak Volcanics FIGURE No. Ilb JOB No. 00-7780 EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Strata Drill 30" diameter boring 5/15/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 214' Mean Sea Level -36' JKH FIELD DESCRIPTION AND CLASSIFICATION re w ° o K + ° M° a DESCRIPTION AND REMARKS M V) o ~ ig z ai o (Groin size, Density, Moisture, Color) vi 15 ? 1 W ? a 3 o iaK 3 oo mU a ~c~ Z o o 0 . CJ 2 SANDY CLAY with some caliche. Firm. CL Moist. Dark brown. 4 TOPSOIL/SLOPEWASH 6 8 SILTSTONE/CLAYSTONE, highly fractured & ML jumbled. Firm. Damp to moist. Dark 10 gray-green. 12 14 QLS 16 N65°E ±450NE zt- SILTY FINE SAND/SANDY SILTY with some clay SM/ seams & siltstone fragments. Medium dense ML ~'k;•.. (firm). Damp. Tan-gray. 20 t j ....fi 22 Disturbed r31 r Td/Tf FORMATION/Ql s 24 Aq; .fJ{.1 26 Gradational contact N70°E 30°S Q WATER TABLE ® LOOSE BAG SAMPLE IN-PLACE SAMPLE 0 DRNE SAMPLE n SAND CONE/F.D.T. ® STANDARD PENETRATION TEST JOB NAME Creighton Residence Additions SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER REVIEWED BYJAC/LDR LOG No. 00_»80 Bwl FIGURE NUMBER' Ilia EQUIPMENT DIMENSION do TYPE OF EXCAVATION DATE LOGGED Strata Drill 30" diameter boring 5/15/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 214' Mean Sea Level -36' JKH FIELD DESCRIPTION AND CLASSIFICATION W W W a a + ! o °m na. DESCRIPTION AND REMARKS j N ' , m m o (Grain size, Density, Moisture, Color) C3 j z z o In o L 1 3 2 I 1-be 60 m U v 1.-iit~ ' SILTY FINE TO COARSE SAND, poorly cemented. SM 30 - i-i-I Medium dense. Damp. Tan-gray. 32- r: :1' . .1 1 1 - hit dense concretionary SS layer 34 SANDSTONE (fine to coarse grained) with SM r " some interbedded layers of concretionary SS boulders. Dense. Moist to wet. Tan- 36 gray. 38 _ Very dense drilling-broke through with core barrel Assum ed slip p ane d epth @ 40 40 ` Interbedded siltstone & sandstone Could not veri fy due to water & cav ing Disturbed Td/Tf FORMATION/Qls 44 Bottom @ 44' 46 Logged hole with 5' of water in bottom 48- Extensive caving @ 38' 50 52 54 0 10 a WATER TABLE IJOB NAME Creighton Residence Additions LOOSE BAG SAMPLE IN-PLACE SAMPLE DRIVE SAMPLE SAND CONE/F.D.T. STANDARD PENETRATION TEST SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER 00-7780 FIGURE NUMBER Illb REVIEWED BYJAC/LDR MIMI .,,h. LOG No. B-1 cont. EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED Strata Drill 30" diameter boring 5/15/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 180' Mean Sea Level Not encountered JKH FIELD DESCRIPTION AND CLASSIFICATION K v w O O J W WW W W °m a DESCRIPTION AND REMARKS a 5 c _j za o z a~ o „ (Grain size, Density, Moisture, Color) = z5 zW f 5 o :Z 3 C3 m U CLAYEY SAND with some roots & rock fragment SC 2 ,%n3 Loose. Dry to damp. Tan-gray & dark brown yet FILL/TOPSOIL 4 SANDY CLAY with some roots & rock fragments CL Firm. Damp. Gray-green & brown. 6 FILL/Qls 8 Assumed sl ip plane depth @ 8' - 10' 1 CLAYSTONE with some caliche & iron oxide 10 F/ staining & pebble/gravel stringer. Firm. - 8' pebbles 14" dip to 55°W - Moist. Dark gray-green & orange. - becomes very ense @ 8' " caliche blebs (not cont nuou ) within a ark 12 Claystone broken into small gravel size gray-gr en & eddish br wn c ayston nea pieces highly broken/disturbed. horizon al co tact 14 Disturbed Td/Tf FORMATION 16 2 SANDSTONE, poorly to moderately cemented. SM 3 ense. Damp. Tan-gray. i 18 CLAYSTONE, well indurated with some shiny ML 20 parting surfaces & iron oxide staining. Td/Tf FORMATION 22 Bottom @ 20' 24- 26- WATER TABLE ® LOOSE BAG SAMPLE 11 IN-PLACE SAMPLE N DRIVE SAMPLE 0 SAND CONE/F.D.T. ® STANDARD PENETRATION TEST JOB NAME Creighton Residence Additions SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER REVIEWED BYJAC/LDR LOG No. 00-7780 woaa.~ica~ FIGURE NUMBER Nq*wftMkm Bm2 Illc EQUIPMENT DIMENSION do TYPE OF EXCAVATION DATE LOGGED Strata Drill 30" diameter boring 5/15/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 182' Mean Sea Level Not encountered JKH FIELD DESCRIPTION ^ AND 82 CLASSIFICATION W W w° W v + ! °o o ~ m DESCRIPTION AND REMARKS 6 CL a c N 3 as (Grain size, Density, Moisture, Color) v; . 15 JE Zw P o w wK o ° o z o p g O a~ U M U l 1 2 ~f'r SANDY CLAY with some coarse rock fragments. CL ~ j. Firm. Damp. Medium brown. 4 ~j 6 j FILL/Ql s Ass d slip p lane pth @ 8'- 10' Z/, CLAYSTONE, moderately fractured with some CL 10 caliche & iron oxide staining. Stiff. /i Damp. Dark gray-green &orange. 12- 4 ' 14 f ti . SANDSTONE, moderately well cemented with 16 some iron oxide staining & banding. Medium t.i`•i' ense. Damp. Tan-gray. 18 SILTY FINE SAND, well cemented. Dense. Damp. Light gray. 20 CLAYSTONE, massive with some iron oxide CL staining. Hard. Damp. Dark gray-green & ran e. Td/Tf FORMATION Bottom @ 21' Horizontal bedding features Q WATER TABLE JOB NAME Creighton Residence Additions ® LOOSE BAG SAMPLE SITE LOCATION 1Q IN-PLACE SAMPLE 2902 Lone Jack Road, Encinitas, CA. DRNE SAMPLE JOB NUMBER REVIEWED B'JAC/LDR LOG No. SAND CONE/F.D.T. 00-7780 AftALIA, a.oondw*w wmae 3 = FlGURE NUMBER . 10 STANDARD PENETRATION TEST Illd EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED E-100 Bucket Drill Rig 30" diameter boring 6/8/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY ± 208' Mean Sea Level Not encountered JKH FIELD DESCRIPTION AND CLASSIFICATION W W 41 x W w ° o x + o °m a DESCRIPTION AND REMARKS v s o V) zd Ca (Grain size, Density, Moisture, Color) vi o n w Z F o w 3 o a z ° OM ° M~ W U mU G j t- SANDY CLAY with some roots. Soft to firm. CL Moist. Dark brown. FILL/TOPSOIL SILTSTONE/CLAYSTONE, highly fractured with ML/ some sand & caliche lenses. Firm to stiff. MC 4 f4 V Damp. Dark gray-green. 6 8 Af- l Qls 10- ei 12 ' ; , rA, SILTY FINE SAND/SANDY SILT with some clay SM/ 14 ; *T . r. lenses. Medium dense (firm). Dam Tan- p. ML t7{ ~ gray. 16 ;:te ~ a ~ i V'j , - becomes ver cl d i 1$ y ean san w th some iron oxide staining 20- 22- Disturbed Td/Tf FORMATION/Qls i1 SANDY SILT with some siltstone & claystone ML fragments & concretionary sandstone 26 .j1d ITI boulders. Firm. Damp. Tan-gray & green. Q WATER TABLE ® LOOSE BAG SAMPLE 0 IN-PLACE SAMPLE N DRIVE SAMPLE n SAND CONE/F.D.T. ® STANDARD PENETRATION TEST JOB NAME Creighton Residence Additions SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER REVIEWED 9YJAC/LDR LOG No. 00-7780 B-4 FIGURE NUMBER Ille - EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED E-100 Bucket Drill Rig 30" diameter boring 6/8/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 208' Mean Sea Level -30' JKH FIELD DESCRIPTION AND CLASSIFICATION >K W W W_ K W ^ ° + i o m° a DESCRIPTION AND REMARKS q L ~ a w ~ 0 7d tn 3 a= o „ (Grain size, Density, Moisture, Color) vi . n i o ? } W Z FL M x p o MB 9 M O o W U fy SILTY FINE TO COARSE SAND, poorly to SM 30 moderately cemented with some concretionary sandstone boulders. Medium dense. Damp to moist. Tan-gray & green. 32 j,;F `r..: Ql s 34 harder drilling with some larger concre- tionary boulders. N30°W 30SW slip plane " thick.-remolded cla y seam Slip p lane d epth i CLAYSTONE massive & m d t l 36 , o era e y well !f indurated. Hard. Damp. Dark gray- green. 3' thick claystone bed. 38 SILTY SANDSTONE (fine to medium grained). SM 40- ;~;r=! 5 1 Ir i Medium dense. Damp. Tan-gray & orange. ° ° - N20 W 5 SW becomes very orange oxide stained sand 42 i' CLAYSTONE, well indurated with some shiny 44 parting surfaces. Hard. Damp. Dark gray- green & brown. 46 F 48 /z 50 Td/Tf FORMATION 52 I I~ SILTSTONE, with slight clay massive and CL 1 indurated. Hard. Damp. Dark gray. 54- 1 WATER TABLE ® LOOSE BAG SAMPLE 0 IN-PLACE SAMPLE N DRIVE SAMPLE 0 SAND CONE/F.D.T. 0 _STANDARD STANDARD PENETRATION TEST JOB NAME Creighton Residence Additions SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER REVIEWED BYJAC/LDR 00-7780 fiwo~dMled FIGURE NUMBER lllf LOG No. B-4 cont. EQUIPMENT DIMENSION & TYPE OF EXCAVATION DATE LOGGED E-100 Bucket Drill Rig 30" diameter boring 6/8/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 208' Mean Sea Level -30' JKH FIELD DESCRIPTION ~ AND x a v o a o K o CLASSIFICATION C3 `J` cWi it cWv ~ + M a DESCRIPTION AND REMARKS Cn 5 S~ ° ~ 3 ax 9 ~W 0 o (Grain size, Density, Moisture, Color) vUi ai s 1i X in o °c~ LLI Z~ ?0 C)MD aK W U JO Z m U 58 CLAYSTONE, massive & well indurated. Hard CL j Damp. Dark gray. 60 62 / Td/Tf FORMATION i 64 66 Bottom @ 64' 68- V WATER TABLE JOB NAME _ Creighton Residence Additions ® LOOSE BAG SAMPLE SITE LOCATION 10 IN-PLACE SAMPLE 2902 Lone Jack Road, Encinitas, CA. DRIVE SAMPLE JOB NUMBER REVIEWED BYJAC/LDR LOG No. 00-7780 SAND CONE/F.D.T. FIGURE NUMBER B-4 ® STANDARD PENETRATION TEST Illg cont. EQUIPMENT DIMENSION do TYPE OF EXCAVATION DATE LOGGED Case Backhoe 2' x 10' x 6' Trench 211100 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY N/A Not encountered JKH FIELD DESCRIPTION AND CLASSIFICATION v ° o + o J °m a DESCRIPTION AND REMARKS W a W Fn ~ En Cn \ i a o (Grain size, Density, Moisture, Color) i z o z r3° a z ° 3 o v ? ? o o c ~ m L) SANDY SILT with some clay, gravel & ML 'I1 sandstone fragments. Soft to firm. Dry. Gray-brown. . ~ F t 1# FILL/TOPSOIL 2 SANDY CLAY with some roots & deep CL %t expansion cracks (to 3' to 4'). Firm. Damp to moist. Dark brown. 3 i ?f/ TOPSOIL 4 f SANDY SILT/SILTY SANDSTONE, with some SM/ : ar caliche, moderately well cemented. Dense. ML i 4 Damp. Light gray-green. a 5 F FORMATION/Td/Tf 6 Bottom @ 6' WATER TABLE JOB NAME Creighton Residence Additions ® LOOSE BAG SAMPLE SITE LOCATION ] IN-PLACE SAMPLE 2902 Lone Jack Road, Encinitas, CA. DRIVE SAMPLE JOB NUMBER REVIEWED BYJAC/LDR LOG No. SAND CONE/F.D.T. 00-7780 FIGURE NUMBER 4PA T= I ® STANDARD P ENETRATION TEST Illh EQUIPMENT DIMENSION do TYPE OF EXCAVATION DATE LOGGED Case Backhoe 2' x 10' x 5' Trench 2/1/00 SURFACE ELEVATION GROUNDWATER DEPTH LOGGED BY t 208' Mean Sea Level Not encountered JKH FIELD DESCRIPTION ^ AND K W K O CLASSIFICATION v L v ~ v Lq + ° a w ff m DESCRIPTION AND REMARKS L En cn o En W CL= C (Grain size, Density, Moisture, Color) N . Z5 Zw o w CL o i ° o QmQz p O M psi .a.l U MU Nv 2" ASPHALT WITH SAND BASE SANDY CLAY with abundant roots. Stiff to CL firm. Moist. Dark brown. TOPSOIL 2 Y f' SANDY SILT/SILTY SAND with slight clay & SM/ r` some caliche. Medium dense to dense. Damp. Light gray-green. 3 + t 4 ; tt / •~Y FORMATION/Td/Tf 4 5 Bottom @ 5' 6 WATER TABLE ® LOOSE BAG SAMPLE it IN-PLACE SAMPLE DRIVE SAMPLE SAND CONE/F.D.T. STANDARD PENETRATION TEST JOB NAME Creighton Residence Additions SITE LOCATION 2902 Lone Jack Road, Encinitas, CA. JOB NUMBER REVIEWED BYJAC/LDR LOG No. 00-7780 FIGURE NUMBER T=2 Illi 0 aOD •o 00 Q o o a` o o °0N 0 0 0 0 o Z ^ C U Q W N N N N 04 W O o r` O. N 3 Z = mod ► I I I I I I I mo Ti 75 0 2 o I , C LL r12 0 0, rn o d Z - U U U - C ca W - O m _ O - Q X - w _ U - O •c - tp t U N - O - m U r - Cl N t0 - N r - N 0 - L +J 4) - +1 +i O 00 LO W O O N et - r C 11 fa ^ ^ b - UI U_ CL r N C d d A O N r N $ - 10. a - 4J M- N co _ I I 10 3 c'7 _ O - _ ■ IL d (n O O -0 U - M d .g - O CL v N co - N C W O - N N r~ ~ CO _ o U CL V _ co N - w E ` - 8 . o o ~ 0 ` C,4 ca d v N - o N - 8 - ( J J O - ~ i U 0 _ r C4 - W /E m O e~ 0 40 I I I I I I I _ 0 I I I I I I I I I _ O N O NO O O O O O N N - ` N - . - 140 `I ' 130 120 u a 110 ~ I o 100 90 MAXIMUM DRY DENSITY (pcf) OPTIMUM MOISTURE CONTENT (Z ) 80 ul 0 SOIL TYPE 1 2 I 3 LABORATORY SOIL DATA SUMMARY (85% RC) Remolded Slide Plane Soil DIRECT SHEAR TEST I 2 3 DATA APPARENT COHESION (psf) 260 475 APPARENT FRICTION ANGLE 3.5 3.0 Gravel Sand Fines Coarse To Medium Fine Silt Clay I-S. standard sieve sizes N R O O 1 2 110.2 15.5 100 80 60 W 40 6 20 0 3 ZERO AIR VOIDS CURVES 10 20 30 LABORATORY COMPACTION TEST SOIL CLASSIFICATION Green-'tan silty clay SWELL TEST DATA 1 INITIAL DRY DENSITY (pcf) ' 100 INITIAL RATER CONTENT (X) 14.2 LOAD (psf) 144 PERCENT SWELLExpans i on I ndex 78 2 1 3 40 BORING TRENCH DEPTH No. No. B-1 5'-10' FIGURE NUMBER V JOB NUMBER 00-7780 co -w 70 C> C, ° ° 0 0 ° o 0 GRAIN DIAMETER., mm - 2.70 2.60 2.50 SPECIFIC GRAVITY i FOUNDATION REQUIREMENTS NEAR SLOPES I PROPOSED STRUCTURE TOP OF COMPACTED FILL SLOPE I (Any loose soils on the slope surface CONCRETE FLOOR SLAB shall not be considered to provide lateral or vertical strength for the SETBACK footing or for slope stability. Needed 88 depth of imbedment shall be measured from competent soil.) I\~'~''*'~ ' " ► - ~ ' ' ' - COMPACTED FILL SLOPE WITH • • : • ~ . MAXIMUM INCLINATION AS REINFORCEMENT OF • PER SOILS REPORT FOUNDATIONS AND FLOOR \ \ z SLABS FOLLOWING THE TOTAL DEPTH OF FOOTING MEASURED RECOMMENDATIONS OF THE '4 • FROM FINISH SOIL SUB-GRADE I ARCHITECT OR STRUCTURAL ENGINEER 14 '4 • • • \ COMPACTED FILL CONCRETE FOUNDATION ; . ► • \ ~ _ 18" MINIMUM OR AS DEEP AS RE UIR \ OUTER E Q ED FOR LATERAL MOST FAC 8' STABILITY OF FOOTING TYPICAL SECTION (SHOWING PROPOSED FOUNDATION LOCATED WITHIN 8 FEET OF TOP OF SLOPE) 18" FOOTING / 8' SETBACK TOTAL DEPTH OF FOOTING 1.5:1.0 SLOPE 2.0:1.0 SLOPE o 0.. o LL .J W Ln U U. Z p Q 0. F' O N ~ D 0' 82" 66" 2' 6611 5411 4' 51" 4211 6' 34" 30" 8' 18" 1811 • # when applicable I FIGURE NUMBER VI JOB NUMBER 00-7780 APPENDIX A APPENDIX A UNIFIED SOIL CLASSIFICATION CHART SOIL DESCRIPTION Coarse-grained (More than half of material is larger than a No. 200 sieve) GRAVELS, CLEAN GRAVELS GW Well-graded gravels, gravel and sand mixtures, little (More than half of coarse fraction or no fines. is larger than No. 4 sieve size, but smaller than 3") GP Poorly raded I GRAVELS WITH FINES (Appreciable amount) SANDS, CLEAN SANDS (More than half of coarse fraction is smaller than a No. 4 sieve) SANDS WITH FINES (Appreciable amount) U grave s, gravel and sand mixtures, little or no fines. GC Clay gravels, poorly graded gravel-sand-silt mixtures . SW Well-graded sand, gravelly sands, little or no fines SP Poorly graded sands, gravelly sands, little or no fines. SM Silty sands, poorly graded sand and silty mixtures. SC Clayey sands, poorly graded sand and clay mixtures. FINE-GRAINED (More than half of material is smaller than a No. 200 sieve) SILTS AND CLAYS ML Inorganic silts d Liquid Limit Less than 50 Liquid Limit Greater than 50 HIGHLY ORGANIC SOILS an very fine sands, rock flour, sandy silt and clayey-silt sand mixtures with a slight plasticity. CL Inorganic clays of low to medium plasticity, gravelly clays, silty clays, clean clays. OL Organic silts and organic silty clays of low plasticity. MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts. CH Inorganic clays of high plasticity, fat clays. OH Organic clays of medium to high plasticity. PT Peat and other highly organic soils APPENDIX B APPENDIX B GENERAL EARTHWORK SPECIFICATIONS General The objective of these specifications is to properly establish procedures for the clearing and preparation of the existing natural ground or properly compacted fill to receive new fill; for the selection of the fill material; and for the fill compaction and testing methods to be used. Scope of Work The earthwork includes all the activities and resources provided by the contractor to construct in a good workmanlike manner all the grades of the filled areas shown in the plans. The major items of work covered in this section include all clearing and grubbing, removing and disposing of materials, preparing areas to be filled, compacting of fill, compacting of backfills, subdrain installations, and all other work necessary to complete the grading of the filled areas. Site Visit and Site Investigation 1. The contractor shall visit the site and carefully study it, and make all inspections necessary in order to determine the full extent of the work required to complete all grading in conformance with the drawings and specifications. The contractor shall satisfy himself as to the nature, location, and extent of the work conditions, the conformation and condition of the existing ground surface; and the type of equipment, labor, and facilities needed prior to and during prosecution of the work. The contractor shall satisfy himself as to the character, quality, and quantity of surface and subsurface materials or obstacles to be encountered. Any inaccuracies or discrepancies between the actual field conditions and the drawings, or between the drawings and specifications, must be brought to the engineer's attention in order to clarify the exact nature of the work to be performed. 2. A soils investigation report has been prepared for this project by GEL It is available for review and should be used as a reference to the surface and subsurface soil and bedrock conditions on this project. Any recommendations made in the report of the soil investigation or subsequent reports shall become an addendum to these specifications. Authority of the Soils Engineer and Engineering Geologist The soils engineer shall be the owner's representative to observe and test the construction of fills. Excavation and the placing of fill shall be under the observation of the soils engineer and his/her representative, and he/she shall give a written opinion regarding conformance with the specifications upon completion of grading. The soils engineer shall have the authority to cause the removal and replacement of porous topsoils, uncompacted or improperly compacted fills, disturbed bedrock materials, and soft alluvium, and shall have the authority to approve or reject materials proposed for use in the compacted fill areas. The soils engineer shall have, in conjunction with the engineering geologist, the authority to approve the preparation of natural ground and toe-of-fill benches to receive fill material. The engineering geologist shall have the authority to evaluate the stability of the existing or proposed slopes, and to evaluate the necessity of remedial measures. If any unstable condition is being created by cutting or filling, the engineering geologist and/or soils engineer shall advise the contractor and owner immediately, and prohibit grading in the affected area until such time as corrective measures are taken. The owner shall decide all questions regarding: (1) the interpretation of the drawings and specifications, (2) the acceptable fulfillment of the contract on the part of the contractor, and (3) the matter of compensation. J Appendix B Page 2 Clearing and Grubbing 1. Clearing and grubbing shall consist of the removal from all areas to be graded of all surface trash, abandoned improvements, paving, culverts, pipe, and vegetation (including but not limited to heavy weed growth, trees, stumps, logs and roots larger than 1-inch in diameter). 2. All organic and inorganic materials resulting from the clearing and grubbing operations shall be collected, piled, and disposed of by the contractor to give the cleared areas a neat and finished appearance. Burning of combustible materials on-site shall not be permitted unless allowed by local regulations, and at such times and in such a manner to prevent the fire from spreading to areas adjoining the property or cleared area. 3. It is understood that minor amounts of organic materials may remain in the fill soils due to the near impossibility of complete removal. The amount remaining, however, must be considered negligible, and in no case can be allowed to occur in concentrations or total quantities sufficient to contribute to settlement upon decomposition. Preparation of Areas to be Filled After clearing and grubbing, all uncompacted or improperly compacted fills, soft or loose soils, or unsuitable materials, shall be removed to expose competent natural ground, undisturbed bedrock, or properly compacted fill as indicated in the soils investigation report or by our field representative. Where the unsuitable materials are exposed in final graded areas, they shall be removed and replaced as compacted fill. 2. The ground surface exposed after removal of unsuitable soils shall be scarified to a depth of at least 6 inches, brought to the specified moisture content, and then the scarified ground compacted to at least the specified density. Where undisturbed bedrock is exposed at the surface, scarification and recompaction shall not be required. 3. All areas to receive compacted fill, including all removal areas and toe-of-fill benches, shall be observed and approved by the soils engineer and/or engineering geologist prior to placing compacted fill. 4. Where fills are made on hillsides or exposed slope areas with gradients greater than 20 percent, horizontal benches shall be cut into firm, undisturbed, natural ground in order to provide both lateral and vertical stability. This is to provide a horizontal base so that each layer is placed and compacted on a horizontal plane. The initial bench at the toe of the fill shall be at least 10 feet in width on firm, undisturbed, natural ground at the elevation of the toe stake placed at the bottom of the design slope. The engineer shall determine the width and frequency of all succeeding benches, which will vary with the soil conditions and the steepness of the slope. Ground slopes flatter than 20 percent (5.0:1.0) shall be benched when considered necessary by the soils engineer. Fill and Backfill Material Unless otherwise specified, the on-site material obtained from the project excavations may be used as fill or backfill, provided that all organic material, rubbish, debris, and other objectionable material contained therein is first removed. In the event that expansive materials are encountered during foundation excavations within 3 feet of finished grade and they have not been properly processed, they shall be entirely removed or thoroughly mixed with good, granular material before incorporating them in fills. No footing shall be allowed to bear on soils which, in the opinion of the soils engineer, are detrimentally expansive unless designed for this clayey condition. However, rocks, boulders, broken Portland cement concrete, and :bituminous-type pavement obtained from the project excavations may be permitted in the backfill or fill with the following limitations: Appendix B Page 3 1. The maximum dimension of any piece used in the top 10 feet shall be no larger than 6 inches. 2 Clods or hard lumps of earth of 6 inches in greatest dimension shall be broken up before compacting the material in fill. 3. If the fill material originating from the project excavation contains large rocks, boulders, or hard lumps that cannot be broken readily, pieces ranging from 6 inches in diameter to 2 feet in maximum dimension may be used in fills below final subgrade if all pieces are placed in such a manner (such as windrows) as to eliminate nesting or voids between them. No rocks over 4 feet will be allowed in the fill. 4. Pieces larger than 6 inches shall not be placed within 12 inches of any structure. 5. Pieces larger than 3 inches shall not be placed within 12 inches of the subgrade for paving. 6. Rockfills containing less than 40 percent of soil passing 3/4-inch sieve may be permitted in designated areas. Specific recommendations shall be made by the soils engineer and be subject to approval by the city engineer. 7. Continuous observation by the soils engineer is required during rock placement. 8. Special and/or additional recommendations may be provided in writing by the soils engineer to modify, clarify, or amplify these specifications. 9. During grading operations, soil types other than those analyzed in the soil investigation report may be encountered by the contractor. The soils engineer shall be consulted to evaluate the suitability of these soils as fill materials. Placing and Compacting Fill Material After preparing the areas to be filled, the approved fill material shall be placed in approximately horizontal layers, with lift thickness compatible to the material being placed and the type of equipment being used. Unless otherwise approved by the soils engineer, each layer spread for compaction shall not exceed 8 inches of loose thickness. Adequate drainage of the fill shall be provided at all times during the construction period. 2. When the moisture content of the fill material is below that specified by the engineer, water shall be added to it until the moisture content is as specified. 3. When the moisture content of the fill material is above that specified by the engineer, resulting in inadequate compaction or unstable fill, the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is as specified. 4. After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted to not less than the density set forth in the specifications. Compaction shall be accomplished with sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other approved types of acceptable compaction equipment. Equipment shall be of such design that it will be able to compact the fill to the specified relative compaction. Compaction shall cover the entire fill area, and the equipment shall make sufficient trips to ensure that the desired density has been obtained throughout the entire fill. At locations where it would be impractical due to inaccessibility of rolling compacting equipment, fill layers shall be compacted to the specified requirements by hand-directed compaction equipment. ph, 0 T~ Appendix B Page 4 5. When soil types or combination of soil types are encountered which tend to develop densely packed surfaces as a result of spreading or compacting operations, the surface of each layer of fill shall be sufficiently roughened after compaction to ensure bond to the succeeding layer. 6. Unless otherwise specified, fill slopes shall not be steeper than 2.0 horizontal to 1.0 vertical. In general, fill slopes shall be finished in conformance with the lines and grades shown on the plans. The surface of fill slopes shall be overfilled to a distance from finished slopes such that it will allow compaction equipment to operate freely within the zone of the finished slope, and then cut back to the finished grade to expose the compacted core. Alternate compaction procedures include the backrolling of slopes with sheepsfoot rollers in increments of 3 to 5 feet in elevation gain. Alternate methods may be used by the contractor, but they shall be evaluated for approval by the soils engineer. 7. Unless otherwise specified, all allowed expansive fill material shall be compacted to a moisture content of approximately 2 to 4 percent above the optimum moisture content. Nonexpansive fill shall be compacted at near-optimum moisture content. All fill shall be compacted, unless otherwise specified, to a relative compaction not less than 95 percent for fill in the upper 12 inches of subgrades under areas to be paved with asphalt concrete or Portland concrete, and not less than 90 percent for other fill. The relative compaction is the ratio of the dry unit weight of the compacted fill to the laboratory maximum dry unit weight of a sample of the same soil, obtained in accordance with A.S.T.M. D-1557 test method. 8. The observation and periodic testing by the soils engineer are intended to provide the contractor with an ongoing measure of the quality of the fill compaction operation. It is the responsibility of the grading contractor to utilize this information to establish the degrees of compactive effort required on the project. More importantly, it is the responsibility of the grading contractor to ensure that proper compactive effort is applied at all times during the grading operation, including during the absence of soils engineering representatives. Trench Backfill 1. Trench excavations which extend under graded lots, paved areas, areas under the influence of structural loading, in slopes or close to slope areas, shall be backfilled under the observations and testing of the soils engineer. All trenches not falling within the aforementioned locations shall be backfilled in accordance with the City or County regulating agency specifications. 2. Unless otherwise specified, the minimum degree of compaction shall be 90 percent of the laboratory maximum dry density. 3. Any soft, spongy, unstable, or other similar material encountered in the trench excavation upon which the bedding material or pipe is to be placed, shall be removed to a depth recommended by the soils engineer and replaced with bedding materials suitably densified. Bedding material shall first be placed so that the pipe is supported for the full length of the barrel with full bearing on the bottom segment. After the needed testing of the pipe is accomplished, the bedding shall be completed to at least 1 foot on top of the pipe. The bedding shall be properly densified before backfill is placed. Bedding shall consist of granular material with a sand equivalent not less than 30, or other material approved by the engineer. 4. No rocks greater than 6 inches in diameter will be allowed in the backfill placed between 1 foot above the pipe and 1 foot below finished subgrade. Rocks greater than 2.5 inches in any dimension will not be allowed in the backfill placed within 1 foot of pavement subgrade. Appendix B Page 5 5. Material for mechanically compacted backfill shall be placed in lifts of horizontal layers and properly moistened prior to compaction. In addition, the layers shall have a thickness compatible with the material being placed and the type of equipment being used. Each layer shall be evenly spread, moistened or dried, and then tamped or rolled until the specified relative compaction has been attained. 6. Backfill shall be mechanically compacted by means of tamping rollers, sheepsfoot rollers, pneumatic tire rollers, vibratory rollers, or other mechanical tampers. Impact-type pavement breakers (stompers) will not be permitted over clay, asbestos cement, plastic, cast iron, or nonreinforced concrete pipe. Permission to use specific compaction equipment shall not be construed as guaranteeing or implying that the use of such equipment will not result in damage to adjacent ground, existing improvements, or improvements installed under the contract. The contractor shall make his/her own determination in this regard. 7. Jetting shall not be permitted as a compaction method unless the soils engineer allows it in writing. 8. Clean granular material shall not be used as backfill or bedding in trenches located in slope areas or within a distance of 10 feet of the top of slopes unless provisions are made for a drainage system to mitigate the potential buildup of seepage forces into the slope mass. Observations and Testing The soils engineers or their representatives shall sufficiently observe and test the grading operations so that they can state their opinion as to whether or not the fill was constructed in accordance with the specifications. 2. The soils engineers or their representatives shall take sufficient density tests during the placement of compacted fill. The contractor should assist the soils engineer and/or his/her representative by digging test pits for removal determinations and/or for testing compacted fill. In addition, the contractor should cooperate with the soils engineer by removing or shutting down equipment from the area being tested. 3. Fill shall be tested for compliance with the recommended relative compaction and moisture conditions. Field density testing should be performed by using approved methods by A.S.T.M., such as A.S.T.M. D1556, D2922, and/or D2937. Tests to evaluate density of compacted fill should be provided on the basis of not less than one test for each 2-foot vertical lift of the fill, but not less than one test for each 1,000 cubic yards of fill placed. Actual test intervals may vary as field conditions dictate. In fill slopes, approximately half of the tests shall be made at the fill slope, except that not more than one test needs to be made for each 50 horizontal feet of slope in each 2-foot vertical lift. Actual test intervals may vary as field conditions dictate. 4. Fill found not to be in conformance with the grading recommendations should be removed or otherwise handled as recommended by the soils engineer. Site Protection It shall be the grading contractor's obligation to take all measures deemed necessary during grading to maintain adequate safety measures and working conditions, and to provide erosion-control devices for the protection of excavated areas, slope areas, finished work on the site and adjoining properties, from storm damage and flood hazard originating on the project. It shall be the contractor's responsibility to maintain slopes in their as-graded form until all slopes are in satisfactory compliance with the job specifications, all berms and benches have been properly constructed, and all associated drainage devices have been installed and meet the requirements of the specifications. Pik, a Appendix B Page 6 All observations, testing services, and approvals given by the soils engineer and/or geologist shall not relieve the contractor of his/her responsibilities of performing the work in accordance with these specifications. After grading is completed and the soils engineer has finished his/her observations and/or testing of the work, no further excavation or filling shall be done except under his/her observations. Adverse Weather Conditions 1. Precautions shall be taken by the contractor during the performance of site clearing, excavations, and grading to protect the worksite from flooding, ponding, or inundation by poor or improper surface drainage. Temporary provisions shall be made during the rainy season to adequately direct surface drainage away from and off the worksite. Where low areas cannot be avoided, pumps should be kept on hand to continually remove water during periods of rainfall. 2. During periods of rainfall, plastic sheeting shall be kept reasonably accessible to prevent unprotected slopes from becoming saturated. Where necessary during periods of rainfall, the contractor shall install checkdams, desilting basins, rip-rap, sandbags, or other devices or methods necessary to control erosion and provide safe conditions. 3. During periods of rainfall, the soils engineer should be kept informed by the contractor as to the nature of remedial or preventative work being performed (e.g. pumping, placement of sandbags or plastic sheeting, other labor, dozing, etc.). 4. Following periods of rainfall, the contractor shall contact the soils engineer and arrange a walk-over of the site in order to visually assess rain-related damage. The soils engineer may also recommend excavations and testing in order to aid in his/her assessments. At the request of the soils engineer, the contractor shall make excavations in order to evaluate the extent of rain-related damage. 5. Rain-related damage shall be considered to include, but may not be limited to, erosion, silting, saturation, swelling, structural distress, and other adverse conditions identified by the soils engineer. Soil adversely affected shall be classified as Unsuitable Materials, and shall be subject to overexcavation and replacement with compacted fill or other remedial grading, as recommended by the soils engineer. 6. Relatively level areas, where saturated soils and/or erosion gullies exist to depths of greater than 1.0 foot, shall be overexcavated to unaffected, competent material. Where less than 1.0 foot in depth, unsuitable materials may be processed in place to achieve near-optimum moisture conditions, then thoroughly recompacted in accordance with the applicable specifications. If the desired results are not achieved, the affected materials shall be over-excavated, then replaced in accordance with the applicable specifications. 7. In slope areas, where saturated soils and/or erosion gullies exist to depths of greater than 1.0 foot, they shall be overexcavated and replaced as compacted fill in accordance with the applicable specifications. Where affected materials exist to depths of 1.0 foot or less below proposed finished grade, remedial grading by moisture-conditioning in place, followed by thorough recompaction in accordance with the applicable grading guidelines herein presented may be attempted. If materials shall be overexcavated and replaced as compacted fill, it shall be done in accordance with the slope-repair recommendations herein. As field conditions dictate, other slope-repair procedures may be recommended by the soils engineer. ph'. 0 :l APPENDIX C DATE: Wednesday, July 12, 2000 * E Q F A U L T * Ver. 2.20 (Estimation of Peak Horizontal Acceleration From Digitized California Faults) SEARCH PERFORMED FOR: JEFF CREIGHTON JOB NUMBER: 00-7780 JOB NAME: CREIGHTON SITE COORDINATES: LATITUDE: 33.06 N LONGITUDE: 117.23 W SEARCH RADIUS: 100 mi ATTENUATION RELATION: 2) Campbell & Bozorgnia (1994) Horiz. - Soft Rock UNCERTAINTY (M=Mean, S=Mean+1-Sigma): M SCOND: 0 COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: CDMGSCE.DAT SOURCE OF DEPTH VALUES (A=Attenuation File, F=Fault Data File): A t, DETERMINISTIC SITE PARAMETERS '?age 1 MAX. CREDIBL E EVENT - MAX. PROBABL E EVENT APPROX. ABBREVIATED DISTANCE MAX. PEAK SITE MAX. PEAK SITE FAULT NAME mi (km) CRED. SITE INTENS PROB. SITE INTENS MAG. ACC. g MM MAG. ACC. g MM AN ANDREAS - Coachella 74 (119) 7.10 0.022 IV 7.10 0.022 IV SAN ANDREAS - San Bernardi - - 68 (110) 7.30 0.029 V 7.30 0.029 V SAN ANDREAS - Southern - 68 (110) 7.40 0.032 V 7.30 0.029 V SAN ANDREAS - Mojave - - 88 (141) 7.10 0.017 IV 7.10 0.017 IV SAN ANDREAS - 1857 Rupture - 88 (141) 7.80 0.031 V 7.50 0.024 V IMPERIAL - 97 (156) 7.00 0.013 III 7.00 0.013 III SUPERSTITION HILLS (San Ja 81 (130) 6.60 0.012 III 5.90 0.006 II SUPERSTITION MTN. (San Jac 76 (122) 6.60 0.013 III 6.10 0.009 III SAN JACINTO - BORREGO 61 ( 98) 6.60 0.019 IV 6.10 0.012 III SAN JACINTO-COYOTE CREEK - - 50 ( 80) 6.80 0.030 V 6.20 0.017 IV SAN JACINTO-ANZA 48 ( 77) 7.20 0.045 VI 6.90 0.035 V SAN JACINTO-SAN JACINTO-VA 50 ( 81) 6.90 0.032 V 6.80 0.029 V SAN JACINTO-SAN BERNARDINO - 66 (106) 6.70 0.018 - IV 6.70 0.018 IV LAGUNA SALADA - 82 (132) 7.00 0.017 IV 6.30 0.009 III ELSINORE-COYOTE MOUNTAIN 51 ( 82) 6.80 0.029 V 6.20 0.017 IV ELSINORE_JULIAN----------- 25 ( 40) 7.10 0.102 VII 6.40 0.057 VI ELSINORE-TEMECULA--------- -25-(-41) 6.80 0.079 VII 6.30 0.052 VI ELSINORE-GLEN IVY. 41 ( 66) 6.80 0.040 V 6.30 0.026 V WHITTIER 60 ( 96) 6.80 0.023 IV 5.90 0.010 _ III BRAWLEY SEISMIC ZONE - 90 (145) 6.40 0.009 III 6.40 0. ~ JI CHINO CEN - % - TRAL AVE. (Elsino 56 ( 91) 6.70 0.022 IV 5.50 0. . 1 EARTHQUAKE VALLEY 3- -9 (-6-2-) 6.50 0.033 V - 5.70 0 0.016 IV ELMORE RANCH 0 129) 6.60 -0.012 III 5.40 0.004 I CORONADO------------- BANK 21 ( 34) 7.40 0.161 VIII 6.30 0.067 VI PORT-INGLEWOOD (Offshor - 13 ( 21) 6.90 0.193 VIII 5.80 0.081 _ VII DETERMINIST IC SITE - PARAMETERS Page 2 MAX_ CREDIBLE EVENT MAX. PROBABLE EVENT I AP PROX. - ABBREVIATED FAULT NAME DIS TANCE MAX. PEAK SITE MAX. PEAK SITE mi (km) CRED. SITE INTENS PROB. SITE INTENS MAG. ACC. g MM MAG. ACC. g MM OSE-CANYON - 6 - 10) .90 .379 X 5.70 0.182 VIII CLAMSHELL-SAWPIT 88 142) 6.50 0.009 III 5.00 0.003 I CUCAMONGA 8 - (126) 7.00 0.017 IV 6.10 0.008 III IHOLLYWOOD 3 - 150) 6.40 0.008 II 5.30 0.003 I NEWPORT-INGLEWOOD (L.A.Bas 55 - ( 89) 6.90 0.028 V 5 60 0 0 _ - . . 09 III ALOS VERDES 4 - - ( 71) 7.10 0.047 VI 6.20 0.021 IV RA RAYMOND 88 (142) 6.50 0.009 III 5.00 0.003 I -AN JOSE 76 - (123) 6.50 0.012 III 5.00 - 0.003 I SANTA MONICA 8 - - (157) 6.60 - 0.009 III 5.50 - 0.0004 04 ' I IERRA MADRE 9 - (127) 7.00 - 0.017 IV 6.20 - 0.009 II ERDUGO 1 - - (146) 6.70 - 0.010 III 5.20 - 0.003 I COMPTON THRUST I-- TON 65 - (104) 6.80 - 0.029 V 5.80 - 0.013 III E LYSIAN THRUST E-----------PARK- 7 108) .70 - 0.025 V 5.80 - 0.012 - III - - - BURNT MTN. 78 - (126) 6.40 0.011 III 5.10 _ _ 0.003 I LEGHORN - 84 - (135) 6.50 0.011 III 6.00 - 0.007 II. UREKA PEAK 1 - (130) 6.40 - 0.010 III 5.10 - 0.003 I HELENDALE - S. LOCKHARDT 93 - - (149) 7.10 0.016 IV _ 5.40 _ 0.0 I JOHNSON VALLEY (Northern) 98 (157) 6.70 0.010 _ 111 _ 5.20 _ 0. LANDERS - - - - - - - 89 (144) 7.30 0.020 IV 5.20 0.003 I ENWOOD-LOCKHART-OLD WOMAN I 95 (154) 7.30 0.018 IV 5 50 0 004 _ . . I NORTH FRONTAL FAULT ZONE ( 91 (147) 6.70 0.010 III 5.20 0.003 I NORTH FRONTAL FAULT ZONE ( 86 (138) 7.00 0.014 IV 5.60 0.005 II PINTO MOUNTAIN 75 (120) 7.00 0.020 IV 6.10 0.009 III EMERSON So. - COPPER MTN. 97 (155) 6.90 0.012 III 5.30 0.003 I_ Sage 3 -END OF SEARCH- 49 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON FAULT IS CLOSEST TO THE SITE. LT IS ABOUT 6.2 MILES AWAY. LARGEST MAXIMUM-CREDIBLE SITE ACCELERATION: 0.379 g jARGEST MAXIMUM-PROBABLE SITE ACCELERATION: 0.182 g DATE: Wednesday, July 12, 2000 * E Q F A U L T * Ver. 2.20 (Estimation of RHGA Horizontal Acceleration From Digitized California Faults) SEARCH PERFORMED FOR: JEFF CREIGHTON JOB NUMBER: 00-7780 JOB NAME: CREIGHTON SITE COORDINATES: LATITUDE: 33.06 N LONGITUDE: 117.23 W SEARCH RADIUS: 100 mi ATTENUATION RELATION: 2) Campbell & Bozorgnia (1994) Horiz. - Soft Rock UNCERTAINTY (M=Mean, S=Mean+1-Sigma): M SCOND: 0 COMPUTE RHGA HORIZ. ACCEL. (FACTOR: 0.650 DISTANCE: 20.0 mi) FAULT-DATA FILE USED: CDMGSCE.DAT SOURCE OF DEPTH VALUES (A=Attenuation File, F=Fault Data File): A T~ DETERMINISTIC - SITE - PARAMETERS page 1 - MAX. - CREDIBLE -EVENT _ _MAX. _ AP PROX. ABBREVIATED FAULT NAME DISTANCE MAX. RHGA SITE MAX. mi (km) CRED. SITE INTENS PROB. MAG. ACC. g MM MAG. AN ANDREAS - Coachella - 74 (119) 7.10 0.022 IV - 7.10 SAN SAN ANDREAS - San Bernardi 68 (110) 7.30 0.029 V 7.30 ANDREAS - Southern 68 (110) 7.40 0.032 V 7.30 AN ANDREAS - Mojave 88 (141) 7.10 0.017 IV 7.10 SAN ANDREAS - 1857 Rupture 88 (141) 7.80 0.031 V _ 7.50 IMPERIAL 97 (156) 7.00 0.013 III _ 7.00 SUPERSTITION HILLS (San Ja 81 (130) 6.60 0.012 III 5.90 SUPERSTITION MTN. (San Jac - 76 (122) 6.60 - 0.013 III 6.10 SAN JACINTO - BORREGO 61 ( 98) 6.60 0.019 IV _ 6.10 SAN-JACINTO_COYOTE-CREEK-- 50 ( 80) 6_80 - 0_030 V 6,201 SAN JACINTO-ANZA - - - 48 - ( 77) - - 7.20 - 0.045 VI 6.90 AN JACINTO-SAN JACINTO VA 50 ( 81) 6.90 - 0.032 V 6.80 SAN SAN JACINTO-SAN BERNARDINO 66 - f106) 6.70 - 0.018 IV 6.70 LAGUNA SALADA 82 (132) 7.00 - 0.017 IV 6.30 ELSINORE-COYOTE MOUNTAIN 51 82) 6.80 0.029 V _ 6.20 ELSINORE-JULIAN - 25 ( 40) 7.10 0.102 VII 6.40 ELSINORE-TEMECULA 25 ( 41) 6.80 - 0.079 _ _VII_ -6.30 SINORE-GLEN IVY 41 ( 66) 6.80 - 0.040 V 6.30 WHITTIER 60 ( 96) 6.80 - 0.023 IV 5.90 BRAWLEY SEISMIC ZONE - 90 (145) 6.40 0.009 _ III _ 6.40 CHINO-CENTRAL AVE. (Elsino 56 ( 91) 6.70 0.022 IV _ 5.50 PROBABLE EVENT RHGA SITE SITE INTENS ACC. g MM 0.022 IV 0.029 V 0.029 V 0.017 IV 0.024 V 0.013 III 0.006 II 0.009 III 0.012 III 0.017 IV 0.035 V 0.029 V 0.018 IV 0.009 III 0.017 IV 0.057 VI 0.052 VI -0_026 - -V- 0.010 III 0.0 TeII 0. 1 EARTHQUAKE VALLEY 39 ( 62) 6.50 0.033 V _ 5.70 0.016 IV I_LMORE RANCH 80 (129) 6.60 0.012 III 5.40 _ 0.004 I CORONADO BANK 21 ( 34) 7.40 0.161 - VIII 6.30 0.067 VI N EWPORT-INGLEWOOD (Offshor 3 ( 21) .90 .125 II .80 0.053 VI DETERMINISTIC SITE PARAMETERS Page 2 MAX_ CREDIBLE EVENT MAX. PROBABLE EVENT I APPROX. - - - ABBREVIATED FAULT NAME DISTANCE MAX. RHGA SITE MAX. RHGA SITE mi (km) CRED. SITE INTENS PROB. SITE INTENS - MAG. - ACC. g MM MAG. ACC. g MM --SE-CANYON 6 - ( 10) 6.90 0.246 IX 5.70 0.118 VII LAMSHELL-SAWPIT 8 - 142) 6.50 0.009 III 5.00 0.003 I -CAMONGA 8 - - (126) 7.00 0.017 IV 6.10 0.008 III _LLYWOOD 3 - - (150) 6.40 0.008 II 5.30 0.003 I 'NEWPORT-INGLEWOOD (L.A.Bas 55 I-------------------------- ( 89) 6.90 0.028 V 5.60 0.009 _ III ALOS VERDES 4 - - ( 71) 7.10 0.047 VI 6.20 0.021 IV RAYMOND 88 - (142) 6.50 0.009 III 5.00 _ 0.003 I OSE 6 - - (123) 6.50 0.012 III 5.00 0.003 I ANTA MONICA 8 - - (157) 6.60 - 0.009 III 5.50 - 0.004 I - SIERRA MADRE 9 - - (127) 7.00 - 0.017 IV 6.20 - 0.009 III VERDUGO 91 - (146) 6.70 - 0.010 III 5.20 - 0.003 I OMPTON THRUST 5 - (104) 6.80 - 0.029 V 5.80 - 0.013 III ELYSIAN PARK THRUST 67 - - (108) 6.70 - 0.025 V 5.80 0.012 III T MTN . 78 - (126) 6.40 - 0.011 III 5.10 - 0.003 I EGHORN - - - - - 4 - - (135) 6.50 - 0.011 III 6.00 - 0.007 II _ EUREKA PEAK 1 - - (130) - 6.40 - - 0.010 - III 5.10 _ - 0.003 _ I ELENDALE - - - S. - LOCKHARDT - 93 - (149) 7.10 - 0.016 IV 5.40 0.0 I JOHNSON VALLEY (Northern) 98 (157) 6.70 _ 0.010 _ III 5.20 _ 0. 1 i LANDERS 9 (144) .30 .020 ' IV 5.20 0.003 I --NWOOD-LOCKHART-OLD WOMAN 95 154) 7.30 0.018 IV 5.50 0.004 I ORTH FRONTAL FAULT ZONE ( 1 (147) 6.70 0.010 III 5.20 0.003 I NORTH FRONTAL FAULT ZONE ( 86 (138) 7.00 0.014 IV 5.60 0.005 II INTO INTO --------MOUNTAIN- 75 (120) 7.00 0.020 IV 6.10 0.009 III- E MERSON So. - COPPER MTN. 7 (155) 6.90 .012 II .30 .003 I ?age 3 END OF SEARCH- 49 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON FAULT IS CLOSEST TO THE SITE. ?T IS ABOUT 6.2 MILES AWAY. LARGEST MAXIMUM-CREDIBLE SITE ACCELERATION: LARGEST MAXIMUM-PROBABLE SITE ACCELERATION: 0.246 g 0.118 g J APPENDIX D )ATE: Wednesday, July 12, 2000 * E Q S E A R C H * Ver. 2.20 (Estimation of Peak Horizontal Acceleration From California Earthquake Catalogs) SEARCH PERFORMED FOR: JEFF CREIGHTON fOB NUMBER: 00-7780 JOB NAME: CREIGHTON ,ITE COORDINATES: LATITUDE: 33.06 N LONGITUDE: 117.23 W 1'YPE OF SEARCH: RADIUS SEARCH RADIUS: 100 mi SEARCH MAGNITUDES: 5.0 TO 9.0 'EARCH DATES: 1800 TO 1999 1=ENUATION RELATION: 2) Campbell & Bozorgnia (1994) Horiz. - Soft Rock UNCERTAINTY (M=Mean, S=Mean+1-Sigma): M SCOND: 0 FAULT TYPE ASSUMED (DS=Reverse, SS=Strike-Slip): DS COMPUTE PEAK HORIZONTAL ACCELERATION EARTHQUAKE-DATA FILE USED: ALLQUAKE.DAT 2IME PERIOD OF EXPOSURE FOR STATISTICAL COMPARISON: 50 years OURCE OF DEPTH VALUES (A=Attenuation File, E=Earthquake Catalog): A Page 1 FILE LAT. LONG. DATE TIME (GMT) DEPTH QUAKE SITE SITE APPROX. CODE NORTH WEST H Sec (km) MA ACC. MM DIS TANCE - G. g INT. mi [kmJ JMG MGI 33.000 32.800 117.300 117.100 11/22/1800 5/25/1803 2130 0.0 3.0 6.50 0.430 X 6 [ 91 )MG 34.370 117.650 12/ 8/1812 0 0 15 0 0.0 0 0 7.3 5.00 0.030 V 19 [ 31] '-A 34.000 118.250 9/23/1827 0 0 . 0 0 3.0 7 3 7.00 0.013 III 94 [ 1511 MGI " 34.100 118.100 7/11/1855 415 . 0.0 . 3 0 5.00 6 30 0.003 I 88 [ 141] -A 34.000 118.250 1/10/1856 0 0 0.0 . 7 3 . 5 00 0.008 III 88 [ 1411 [GI ' 33.000 117.000 9/21/1856 730 0.0 . 7 3 . 5 00 0.003 I 88 [ 141] 1 -A 32.670 117.170 12/ 0/1856 0 0 0.0 . 7 3 . 5 00 0.049 VI 14 [ 22] MGI ' 34.000 117.500 12/16/1858 10 0 0.0 . 3 0 . 7 00 0.018 IV 27 [ 441 -A 34.000 118.250 3/26/1860 0 0 0 0 . 7 3 . 0.022 IV 67 [ 1071 -MG 32.700 117.200 5/27/1862 20 0 . 0 0 . 4 0 5.00 0.003 I 88 [ 1411 T-A 32.670 117.170 10/21/1862 0 0 . 0 0 . 7 3 5.90 0.043 VI 25 [ 401 '-A 32.670 117.170 5/24/1865 0 0 . 0 0 . 7 3 5.00 0.018 IV 27 [ 441 '-A 33.500 115.820 5/ 0/1868 0 0 . 0 0 . 3 0 5.00 0.018 IV 27 [ 441 T-A 32.250 117.500 1/13/1877 20 0 . 0 0 . 7 3 6.30 0.008 III 87 [ 140] r)MG 33.900 117.200 12/19/1880 0 0 . 0 0 . 3 5 5.00 0.005 II 58 [ 931 MG 34.100 116.700 2/ 7/1889 520 . 0 0 . 6 5 6.00 0.012 III 58 [ 931 uMG 34.200 117.900 8/28/1889 215 . 0.0 . 5 8 5.30 5 50 0.004 I 78 [ 1261 DMG 33.400 116.300 2/ 9/1890 12 6 0.0 . 3 0 . 6 30 0.004 I 88 [ 1411 MG 32.700 116.300 2/24/1892 720 0.0 . 3 0 . 6 70 0.015 IV 59 [ 941 MG 33.200 116.200 5/28/1892 1115 0.0 . 3.0 . 6 30 0.021 0 015 IV 59 [ 961 DMG -MG 34.300 117.600 7/30/1894 512 0.0 3.5 . 6.00 . 0 006 IV II 60 [ 971 MG 32.800 34.200 116.800 117.400 10/23/1894 7/22/1899 23 3 0 0.0 5.0 5.70 . 0.026 V 88 31 [ 1421 [ 491 DMG 34.300 117.500 7/22/1899 46 2032 0.0 0 0 5.8 3 0 5.50 0.005 II 79 [ 1281 CMG 33.800 117.000 12/25/1899 1225 . 0.0 . 3 0 6.50 6 40 0.009 III 87 [ 1401 GI 34.000 118.000 12/25/1903 1745 0.0 . 7.3 . 5 00 0.019 0 003 IV 53 [ 851 .-,GI 34.100 117.300 7/15/1905 2041 0.0 6.5 . 5 30 . 0 005 I 79 [ 1261 KGI 34.000 118.300 9/ 3/1905 540 0.0 6.5 . 5 30 . 0 003 II 72 [ 1161 MG 34.200 117.100 9/20/1907 154 0.0 3.5 . 6 00 . 0 007 I 89 [ 1441 MG 33.700 117.400 4/11/1910 757 0.0 7.3 . 5 00 . 0 008 II 79 [ 1271 DMG " 33.700 117.400 5/13/1910 620 0.0 7.3 . 5 00 . 0 008 III 45 [ 731 MG 33.700 117.400 5/15/1910 1547 0.0 3.5 . 6 00 . 0 018 III 45 [ 731 MG 33.500 116.500 9/30/1916 211 0.0 7.3 . 5 00 . 0 006 IV 45 [ 731 DMG MGI 33.750 33 800 117.000 117 4/21/1918 22322 5.0 3.0 . 6.80 . 0.030 II V 52 [ 49 [ 841 801 MG . 33.750 .600 117.000 4/22/1918 6/ 6/1918 2115 2 0.0 7.3 5.00 0.006 II 55 [ 891 .1 34.000 118.500 11/19/1918 232 2018 0.0 0 0 7.3 7 3 5.00 0.007 II 49 [ 801 DMG 33.200 116.700 1/ 1/1920 235 . 0.0 . 7 3 5.00 5 00 0.002 98 [ 1571 31 34.080 118.260 7/16/1920 18 8 0 0 . 7 3 . 5 00 0.014 IV 32 [ 521 3I DMG 33.200 34.000 116.600 117.250 10/12/1920 7/23/1923 1748 73 . 0.0 . 6.5 . 5.30 0.003 0.014 III 92 [ 38 [ 1481 611 r\MG 34.000 116.000 4/ 3/1926 02 20 8 6.0 0 0 3.0 6.25 0.012 III 65 [ 1041 KG 34.000 118.500 8/ 4/1927 1224 . 0.0 5.8 7 3 5.50 5 00 0.004 I 96 [ 1551 uMG 34.000 116.000 9/ 5/1928 1442 0.0 . 7.3 . 5 00 0.002 0 002 98 [ 1571 DMG SIG 32.900 115.700 10/ 2/1928 19 1 0.0 7.3 . 5.00 . 0 003 1 96 [ 1551 34.180 116.920 1/16/1930 02433.9 6.8 5.20 . 0 004 1 89 [ 1441 . 79 [ 1281 DMG T)MG 34.180 33.617 116.920 117.967 1/16/1930 3/11/1933 034 3.6 1 7.1 5.10 0.004 I 79 [ 1281 )MG 33.750 118.083 3/11/1933 54 7.8 2 9 0 0 3.0 6.30 0.016 IV 57 [ 921 DMG 33.750 118.083 3/11/1933 . 230 0.0 7.3 7 1 5.00 5 10 0.004 I 68 [ 1101 DMG 33.750 118.083 3/11/1933 323 0.0 . 7 3 . 5 00 0.004 I 68 [ 1101 )MG 33.700 118.067 3/11/1933 51022.0 . 7.1 . 5 10 0.004 0 005 I 68 ( 1101 )MG 33.575 117.983 3/11/1933 518 4.0 6.8 . 5 20 . 0 007 II 65 [ 1051 DMG ' 33.683 118.050 3/11/1933 658 3.0 5.8 . 5 50 . 0 007 II 56 [ 901 )MG 33.700 118.067 3/11/1933 85457.0 7.1 . 5 10 . 0 005 II 64 ( 1031 )MG 33.750 118.083 3/11/1933 910 0.0 7.1 . 5 10 . 0 004 II 65 [ 1051 DMG 33.850 118.267 3/11/1933 1425 0.0 7.3 . 5 00 . 0 003 I 68 [ 1101 . . I 81 [ 1301 .dage 2 TIME SITE PILE LAT. LONG. DATE (GMT) DEPTH QUAKE ACC. CODE NORTH WEST H M Sec (km) MAG. _ 9 )MG 33.750 118.083 3/13/1933 131828.0 6 .5 5.30 0.005 DMG 33.617 118.017 3/14/1933 19 150.0 7.1 5.10 0.006 DMG 33.783 118.133 10/ 2/1933 91017.6 6.2 5.40 0.005 )MG 32.083 116.667 11/25/1934 818 0.0 7.3 5.00 0.004 .CMG 31.750 116.500 4/29/1935 20 8 0.0 7.3 5.00 0.002 DMG 34.100 116.800 10/24/1935 1448 7.6 7.1 5.10 0.004 )MG 31.867 116.571 2/27/1937 12918.4 7.3 5.00 0.003 )MG 33.408 116.261 3/25/1937 1649 1.8 3.5 6.00 0.011 DMG 33.699 117.511 5/31/1938 83455.4 5.8 5.50 0.011 DMG 32.000 117.500 5/ 1/1939 2353 0.0 7.3 5.00 0.004 )MG 32.000 117.500 6/24/1939 1627 0.0 7.3 5.00 0.004 DMG 34.083 116.300 5/18/1940 5 358.5 6.2 5.40 0.004 DMG 34.067 116.333 5/18/1940 55120.2 6.8 5.20 0.003 )MG 34.067 116.333 5/18/1940 72132.7 7.3 5.00 0.003 )MG 33.000 116.433 6/ 4/1940 1035 8.3 7.1 5.10 0.008 DMG 33.783 118.250 11/14/1941 84136.3 6.2 5.40 0.005 )MG 32.983 115.983 5/23/1942 154729.0 7.3 5.00 0.004 )MG 32.967 116.000 10/21/1942 162213.0 3.0 6.50 0.013 DMG 32.967 116.000 10/21/1942 162519.0 7.3 5.00 0.004 T)MG 32.967 116.000 10/21/1942 162654.0 7.3 5.00 0.004 )MG 33.233 115.717 10/22/1942 15038.0 5.8 5.50 0.004 .CMG 32.967 116.000 10/22/1942 181326.0 7.3 5.00 0.004 DMG 34.267 116.967 8/29/1943 34513.0 5.8 5.50 0.004 ►MG 33.976 116.721 6/12/1944 104534.7 7.1 5.10 0.004 iMG 33.994 116.712 6/12/1944 111636.0 6.5 5.30 0.005 DMG 33.217 116.133 8/15/1945 175624.0 5.0 5.70 0.008 -)MG 33.000 115.833 1/ 8/1946 185418.0 6.2 5.40 0.004 ,MG 33.950 116.850 9/28/1946 719 9.0 7.3 5.00 0.004 DMG 34.017 116.500 7/24/1947 221046.0 5.8 5.50 0.005 DMG, 34.017 116.500 7/25/1947 04631.0 7.3 5.00 0.003 ,MG 34.017 116.500 7/25/1947 61949.0 6.8 5.20 0.004 .jMG 34.017 116.500 7/26/1947 24941.0 7.1 5.10 0.004 DMG 32.500 118.550 2/24/1948 81510.0 6.5 5.30 0.004 -MG 33.933 116.383 12/ 4/1948 234317.0 3.0 6.50 0.011 MG 32.200 116.550 11/ 4/1949 204238.0 5.0 5.70 0.007 DMG, 32.200 116.550 11/ 5/1949 43524.0 7.1 5.10 0.004 ^MG 33.117 115.567 7/28/1950 175048.0 6.2 5.40 0.003 MG 33.117 115.567 7/29/1950 143632.0 5.8 5.50 0.004 uMG 32.983 115.733 1/24/1951 717 2.6 5.4 5.60 0.005 DMG 32.817 118.350 12/26/1951 04654.0 4.0 5.90 0.009 MG 32.950 115.717 6/14/1953 41729.9 5.8 5.50 0.004 APPROX. DISTANCE mi [km1 SITE MM INT. II II II I I I III III I I I I I III II I III I I I .I I I II III I I II I I I III II I I I II III I 68 59 72 75 100 76 91 61 47 75 75 89 87 87 46 77 72 72 72 72 88 72 85 70 71 64 81 65 78 78 78 78 86 78 71 71 96 96 87 67 88 1101 961 1161 1211 1611 1221 1461 981 761 1201 1201 1431 1391 1391 751 1241 1161 1151 1151 1151 1421 1151 1361 1121 1141 1041 1301 1051 1261 1261 1261 1261 1381 1251 1151 1151 1551 1551 1401 1081 1421 DMG, DMG 33.283 33.283 116.183 116.183 3/19/1954 3/19/1954 95429.0 3.0 6.20 0.013 III 62 [ 100] )MG 33.283 116.183 3/19/1954 95556.0 102117 0 7.3 5 8 5.00 0.005 II 62 [ 100] JMG 33.283 116.183 3/23/1954 . 41450.0 . 7 1 5.50 5 10 0.007 II 62 [ 100] DMG 33.216 115.808 4/25/1957 215738.7 . 6.8 . 5 20 0.005 0 004 II 62 [ 100] )MG )MG 33.183 115.850 4/25/1957 222412.0 7.1 . 5.10 . 0 003 I I 83 [ 133] DMG 33.231 33.710 116.004 116.925 5/26/1957 9/23/1963 155933.6 14 7.3 5.00 . 0.004 I 80 72 [ 129] [ 116] DMG 31.811 117.131 12/22/1964 4152.6 205433 2 7.3 5 4 5.00 0.007 II 48 [ 78] )MG 33.190 116.129 4/ 9/1968 . 22859.1 . 3 0 5.60 6 40 0.005 II 86 [ 139] DMG 33.113 116.037 4/ 9/1968 3 353.5 . 6 8 . 5 20 0.014 IV 64 [ 103] DMG 33.343 116.346 4/28/1969 232042.9 . 4.5 . 5 80 0.005 0 011 II 69 [ 111] )MG CM 34.270 117.540 9/12/1970 143053.0 6.2 . 5.40 . 0 004 III I 55 [ 88] . G PAS 33.033 115.821 9/30/1971 224611.3 7.1 5.10 . 0 003 I 85 [ 137] ?AS 34.327 116.445 3/15/1979 21 716.5 6.8 5.20 . 0 003 I 82 [ 131] ?AS 32.927 115.540 10/16/1979 54910.2 7.1 5.10 . 0 003 98 [ 158] 32.928 115.539 10/16/1979 61948.7 7.1 5.10 . 0 003 98 [ 158] . - 98 [ 158] "age 3 BILE LAT. LONG. DATE TIME (GMT) DEPTH QUAKE SITE ACC SITE APPROX. ;ODE NORTH WEST H M Sec (km) MAG . MM DIS TANCE - - . g INT. mi [km] --'AS ) 33.014 115.555 10/16/1979 65842.8 - 5.8 _ _ 5.50 _ _ 0 004 _ I AS PAS 33.501 33.098 116.513 115.632 2/25/1980 4/26/1981 104738.5 12 5.8 5.50 . 0.010 III 97 51 [ 156] [ 83] PAS 33.998 116.606 7/ 8/1986 928.4 92044.5 5.0 5 4 5.70 5 60 0.005 I 92 [ 149] 'AS 32.971 117.870 7/13/1986 1347 8.2 . 6.5 . 5.30 0.006 0 014 II IV 74 [ 119] 2AS PAS 34.061 34.073 118.079 118.098 10/ 1/1987 10/ 4/1987 144220.0 10 4.0 5.90 . 0.006 II 38 85 [ 60] [ 136] 'AS 33.082 115.775 11/24/1987 5938.2 15414 5 6.5 4 5 5.30 0.004 I 86 [ 138] 'AS 33.013 115.839 11/24/1987 . 131556.5 . 3.5 5.80 6 00 0.006 0 007 II 84 [ 136] PAS 33.919 118.627 1/19/1989 65328.8 7.3 . 5 00 . 0 002 II 81 [ 130] YSP 34.140 117.700 2/28/1990 234336.6 6.8 . 5.20 . 0 004 I 100 [ 161] :SP 34.262 118.002 6/28/1991 144354.5 6.2 5.40 . 0 003 I 79 [ 128] GSP GSN 33.961 34 201 116.318 116 4/23/1992 045023.0 2.9 6.10 . 0.008 II 94 81 [ 151] [ 131] ;SP . 34.139 .436 116.431 6/28/1992 6/28/1992 115734.1 12 3.0 7.60 0.021 IV 91 [ 147] jSP 34.341 116.529 6/28/1992 3640.6 124053 5 7.1 6 8 5.10 0.003 I 88 [ 141] GSP 34.163 116.855 6/28/1992 . 144321.0 . 6.5 5.20 5 30 0.003 0 004 I 97 [ 156] ESN 4SP 34.203 34..108 116.827 116.404 6/28/1992 6/29/1992 150530.7 14 3.0 . 6.70 . 0.012 I III 79 82 [ 127] [ 132] GSP 33.876 116.267 6/29/1992 1338.8 160142 8 6.2 6 8 5.40 0.004 I 87 [ 139] "!SP 34.332 116.462 7/ 1/1992 . 074029.9 . 6.2 5.20 5 40 0.004 0 003 I 79 [ 127] ASP 34.239 116.837 7/ 9/1992 014357.6 6.5 . 5.30 . 0 004 I I 98 [ 158] GSP 33.902 116.284 7/24/1992 181436.2 7.3 5.00 . 0 003 I 84 [ 136] GSP 34.195 116.862 8/17/1992 204152.1 6.5 5.30 . 0 004 I 80 [ 128] ASP 34.064 116.361 9/15/1992 084711.3 6.8 5.20 . 0 003 I 81 [ 131] jSP 34.340 116.900 11/27/1992 160057.5 6.5 5.30 . 0 003 I 85 [ 138] GSP 7 34.369 116.897 12/ 4/1992 020857.5 6.5 5.30 . 0 003 I 90 [ 145] SP 34.029 116.321 8/21/1993 014638.4 7.3 5.00 . 0 003 I 92 [ 149] .SP 34.268 116.402 6/_16/1994 162427.5 7.3 5.00 . 0 002 85 [ 137] . 96 [ 1551 -END OF SEAR CH- 145 RECORDS FOUND ,.OMPUTER TIME REQUIRE D FOR EARTHQUAKE SEARCH: 0.2 min utes AXIMUM SITE ACCELERATION DURING TIME PERIOD 180 0 TO 19 99: 0.4 308 MAXIMUM SITE INTENSITY (MM) DURING TIME PERIOD 1800 TO 1999: MAXIMUM MAGNITUDE ENCOUNTERED IN SEARCH: 7.60 1EAREST HISTORICAL EARTHQUAKE WAS ABOUT NUMBER OF YEARS REPRESENTED BY SEARCH X 6 MILES AWAY FROM SITE. 200 years RESULTS OF PROBABILITY ANALYSES TIME PERIO D OF SEARCH: 1800 TO 1999 jENGTH OF SEARCH TIME: 200 years kTTE NUATION RELATION: 2) TIME PERIOD Campbell & Bozorgnia (1994) Horiz. - Soft Rock OF EXPOSURE FOR PROBABILITY: 50 years ?ROB ABILIT Y OF EXCEEDANCE FOR ACCELERATION NO OF AVE RECUR ACC. . TIMES . OCCUR R. INTERV i COMPUTED PROBABILITY OF EXCEED CE g EXCED . #/yr . years n 0.5 yr in 1 yr in 10 yr in 50 yr in 75 r in 100 in y yr yr ).01 0.02 31 9 0.155 0 045 6.452 0.0746 0.1436 0.7878 0.9996 1.0000 1.0000 0.9996 0.03 4 . 0.020 22.222 50.000 0.0222 0 0100 0.0440 0 0198 0.3624 0.8946 0.9658 0.9889 0.8946 ).04 3 0.015 66.667 . 0.0075 . 0.0149 0.1813 0.1393 0.6321 0 5276 0.7769 0 6753 0.8647 0.6321 0.05 0 06 1 0.005 200.000 0.0025 0.0050 0.0488 . 0.2212 . 0.3127 0.7769 0 3935 0.5276 0 2212 . ).07 1 1 0.005 0.005 200.000 200 000 0.0025 0 0025 0.0050 0.0488 0.2212 0.3127 . 0.3935 . 0.2212 ).08 1 0.005 . 200.000 . 0.0025 0.0050 0.0050 0.0488 0 0488 0.2212 0 2212 0.3127 0.3935 0.2212 0.09 ) 10 1 0.005 200.000 0.0025 0.0050 . 0.0488 . 0.2212 0.3127 0.3127 0.3935 0.3935 0.2212 0 2212 . ).11 1 1 0.005 0 005 200.000 200 000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 0.12 1 . 0.005 . 200.000 0.0025 0 0025 0.0050 0 0050 0.0488 0.2212 0.3127 0.3935 0.2212 0.13 1 0.005 200.000 . 0.0025 . 0.0050 0.0488 0.0488 0.2212 0 2212 0.3127 0 3127 0.3935 0.2212 ).14 J 15 1 0.005 200.000 0.0025 0.0050 0.0488 . 0.2212 . 0.3127 0.3935 0.3935 0.2212 0 2212 . 0.16 1 1 0.005 0 005 200.000 200 000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 ).17 1 . 0.005 . 200.000 0.0025 0.0025 0.0050 0 0050 0.0488 0 0488 0.2212 0.3127 0.3935 0.2212 ).18 1 0.005 200.000 0.0025 . 0.0050 . 0.0488 0.2212 0.2212 0.3127 0 3127 0.3935 0 3935 0.2212 0.19 1 20 1 1 0.005 200.000 0.0025 0.0050 0.0488 0.2212 . 0.3127 . 0.3935 0.2212 0 2212 . ).21 1 0.005 0.005 200.000 200 000 0.0025 0 0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 0.22 1 0.005 . 200.000 . 0.0025 0.0050 0.0050 0.0488 0 0488 0.2212 0 2212 0.3127 0.3935 0.2212 0.23 1 0.005 200.000 0.0025 0.0050 . 0.0488 . 0.2212 0.3127 0.3127 0.3935 0 3935 0.2212 0 2212 ).24 J 25 1 1 0.005 0 005 200.000 2 0.0025 0.0050 0.0488 0.2212 0.3127 . 0.3935 . 0.2212 . 0.26 1 . 0.005 00.000 200.000 0.0025 0 0025 0.0050 0 0050 0.0488 0.2212 0.3127 0.3935 0.2212 1.27 1 0.005 200.000 . 0.0025 . 0.0050 0.0488 0.0488 0.2212 0 2212 0.3127 0 3127 0.3935 0.2212 1.28 0 29 1 0.005 200.000 0.0025 0.0050 0.0488 . 0.2212 . 0.3127 0.3935 0.3935 0.2212 0 2212 . 30 1 1 0.005 0 005 200.000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 . 1.31 1 . 0.005 200.000 200.000 0.0025 0 0025 0.0050 0 0050 0.0488 0.2212 0.3127 0.3935 0.2212 u.32 1 0.005 200.000 . 0.0025 . 0.0050 0.0488 0.0488 0.2212 0 2212 0.3127 0 3127 0.3935 0.2212 0.33 1 34 1 0.005 200.000 0.0025 0.0050 0.0488 . 0.2212 . 0.3127 0.3935 0.3935 0.2212 0 2212 . . 35 1 1 0.005 0 005 200.000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 . 0.36 1 . 0.005 200.000 200 000 0.0025 0 0025 0.0050 0 0.0488 0.2212 0.3127 0.3935 0.2212 -.37 1 0.005 . 200.000 . 0.0025 .0050 0.0050 0.0488 0 0488 0.2212 0 2212 0.3127 0.3935 0.2212 .38 1 0.005 200.000 0.0025 0.0050 . 0.0488 . 0.2212 0.3127 0.3127 0.3935 0 3935 0.2212 0 2212 0.39 40 1 1 0.005 200.000 0.0025 0.0050 0.0488 0.2212 0.3127 . 0.3935 . 0 2212 . .41 1 0.005 0 005 200.000 200 000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 v.42 1 . 0.005 . 200.000 0.0025 0.0025 0.0050 0 0050 0.0488 0 0488 0.2212 0 0.3127 0.3935 0.2212 0.43 1 0.005 200.000 00025 . 0.0050 . 0.0488 .2212 0.2212 0.3127 0 3127 0.3935 0 3935 0.2212 0 - . . .2212 PROBABILITY OF EXCEEDANCE FOR MAGNITUDE NO OF AVE RE AAG. . TIMES . OCCUR CURR. INTERV i COMPUTED PROBABILITY i OF EXCEEDANCE EXCED . ##/yr . years n 0.5 yr n 1 yr in 10 yr in 50 yr in 75 yr in 100 r in y yr 5.00 5 50 145 51 0.725 0 255 1.379 0.3041 0.5157 0.9993 1.0000 1.0000 1.0000 1.0000 . 6.00 26 . 0.130 3.922 7.692 0.1197 0 0629 0.2251 0 1219 0.9219 0 1.0000 1.0000 1.0000 1.0000 6.50 10 0.050 20.000 . 0.0247 . 0.0488 .7275 0.3935 0.9985 0.9179 0.9999 0 9765 1.0000 0 9933 0.9985 0 7.00 750 3 0.015 66.667 0.0075 0.0149 0.1393 0.5276 . 0.6753 . 0.7769 .9179 0 5276 - ----1- -0_005- 200.000 0.0025 0.0050 0.0488 0.2212 0.3127 0.3935 . 0.2212 GUTENBERG & RICHTER RECURRENCE RELATIONSHIP: a-value= 3.565 b-value= 0.746 beta-value= 1.719 APPENDIX E APPENDIX E MODIFIED MERCALLI INTENSITY SCALE OF 1931 (Excerpted from the California Division of Conservation Division of Mines and Geology DMG Note 32) The first scale to reflect earthquake intensities was developed by deRossi of Italy, and Forel of Switzerland, in the 1880s, and is known as the Rossi-Forel Scale. This scale, with values from I to X, was used for about two decades. A need for a more refined scale increased with the advancement of the science of seismology, and in 1902, the Italian seismologist Mercalli devised a new scale on a I to XII range. The Mercalli Scale was modified in 1931 by American seismologists Harry O. Wood and Frank Neumann to take into account modern structural features. The Modified Mercalli Intensity Scale measures the intensity of an earthquake's effects in a given locality, and is perhaps much more meaningful to the layman because it is based on actual observations of earthquake effects at specific places. It should be noted that because the damage used for assigning intensities can be obtained only from direct firsthand reports, considerable time weeks or months is sometimes needed before an intensity map can be assembled for a particular earthquake. On the Modified Mercalli Intensity Scale, values range from I to XII. The most commonly used adaptation covers the range of intensity from the conditions of "1 not felt except by very few, favorably situated," to "XII damage total, lines of sight disturbed, objects thrown into the air" While an earthquake has only one magnitude, it can have many intensities, which decrease with distance from the epicenter. It is difficult to compare magnitude and intensity because intensity is linked with the particular ground and structural conditions of a given area, as well as distance from the earthquake epicenter, while magnitude depends on the energy released at the focus of the earthquake. I Not felt except b a very few under especially favorable circumstances. II Felt only by a few persons at rest, especially on upper floors of buildings. Delicately suspended objects may swin . III Felt quite noticeably indoors, especially on upper floors of buildings, but man earth uake. Standing motor cars may rock slightly. Vibration like passing of truck. plDuration estimated.t as an IV During the day felt indoors by many, outdoors by few. At night some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked notice-'-l . V Felt by nearly everyone, many awakened. Some dishes, windows, etc., broken; a few instances of cracked plaster; unstable objects overturned. Disturbances of trees, poles, and other tall objects sometimes noticed. Pendulum clocks may stop. VI Felt by all, many frightened and run outdoors. Some heavy furniture moved; a few instances of fallen plaster or dama ed chimneys. Damage slight. VII Everybody runs outdoors. Damage negligible in building of good design and construction; slight to moderate in well-built ordinary structures; considerable in poorly built or badly designed structures; some chimneys broken. Noticed b persons driving motor cars. VIII Damage slight in specially designed structures; considerable in ordinary substantial buildings, with partial collapse; great in poorly built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned. Sand and mud ejected in small amounts. Changes in well water. Persons driving motor cars disturbed. IX Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb; great in substantial buildings with partial collapse. Buildings shifted off foundations. Ground cracked cons icuousl Underground pipes broken. X Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked. Rails bent. Landslides considerable from river banks and steep slopes. Shifted sand and mud. Waters lashed (slopped) over banks. XI Few, if any, masonry structures remain standing. Bridges destroyed. Broad fissures in ground. Underground i elines completely out of service. Earth slumps and land slips in soft round. Rails bent greatly. XII Damage total. Practically all works of construction are damaged greatly or destroyed. Waves seen on ground surface. Lines of sight and level are distorted. Objects thrown upward into the air. G4970