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Home My WebLink AboutCD 13-18; FLORAL TRADE CENTER; GEOTECHNICAL INVESTIGATION & UPDATE; 2013-12-23jut 2014 MYLAR SUBMITTAL RECORD Copy / rD fQL 2A71, : U J ate GEOTECHNICAL REPORT 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PREPARED FOR THE MART - CARLSBAD LLC DEL MAR, CALIFORNIA DECEMBER 23, 2013 PROJECT NO. G1076-32-02 I GE000N INCORPORATED 1 GEOTECHNICALu ENVIRONMENTAL IMATERIALS Project No. G1076-32-02 December 23, 2013 The Mart - Carlsbad LLC - 221 15 1h Street Del Mar, California 92014 Attention: Mr. Peter Spencer Subject: UPDATE GEOTECHNICAL REPORT 5600 AVENIDA ENCINAS - CARLSBAD, CALIFORNIA References: 1. Geotechnical Investigation, Carlsbad Office Campus, 5600 Avenida Encinas, Carlsbad, California, prepared by Geocon Incorporated, dated February 24, 2009 (Project No. G 1076-42-01). 2. Grading and Erosion Control Plans For: 5600 Avenida Encinas, Carlsbad, California, Sheet 2, prepared by K&S Engineering, Inc., undated. Dear Mr. Spencer: In accordance with your request, we have prepared this update to the referenced report (Reference No. 1) providing revised geotechnical recommendations and design criteria for the building improvements planned at the subject address. We understand that the proposed development will consist of modifications to the existing commercial building and parking lot, as shown on the referenced plan. We understand that an "L" shaped exterior walkway will bisect the existing building to create two smaller buildings. Parking lot improvements are also planned. We understand that portions of the existing parking lot will be completely removed and replaced, and other areas are planned to be rehabilitated with a grind and overlay. A supplemental report will be prepared that specifically addresses the parking lot improvements. I The geotechnical information presented in this report is necessary to conform to the 2010 California Building Code (CBC) design standards adopted by local agencies after January 1, 2011. The criteria presented below should be used in design and construction of the project. The recommendations presented in the referenced report remain applicable unless superseded herein. For ease of reference, 6960. Ftandes Drive R San Diego, CaliForpiö 92121.2974 U Telephone. 58.558.6900 • :Fa 858.558.6159 I we have included the boring logs and laboratory test results performed by Geocon Incorporated and Leighton and Associates that were provided in the referenced report and are presented in Appendices A and B, respectively. In addition, we have included the Geologic Map, Figure 1, using the current grading plan provided by K&S Engineering, Inc. as the base map. RECOMMENDATIONS 1.0 Seismic Design Criteria 1.1 We used the computer program Seismic Hazard Curves and Unforin Hazard Response Spectra, provided by the USGS. Table I summarizes site-specific design criteria obtained from the 2010 California Building Code (CBC; Based on the 2009 International Building Code [IBC]), Chapter 16 Structural Design, Section 1613 Earthquake Loads. The short spectral response uses a period of 0.2 second. - TABLE 2010 CBC SEISMIC DESIGN PARAMETERS Parameter Value IBC-06 Reference Site Class C Table 16 13.5.2 Spectral Response — Class B (short), 5s 1.320g Figure 1613.5(3) Spectral Response — Class B (1 sec), S1 0.499g Figure 1613.5(4) Site Coefficient, Fa 1.000 Table 1613.5.3(1) Site Coefficient, F 1.301 Table 1613.5.3(2) 'Maximum Considered Earthquake 1.320g Section 1613.5.3 (Eqn. 16-36) Spectral Response Acceleration (short), 5M5 Maximum Considered Earthquake 0.649g Section 1613.5.3 (Eqn 16-37) Spectral Response Acceleration—(1 see), 5M1 5% Damped Design Spectral Response Acceleration (short), 5DS 0.880g Section 1613.5.4 (Eqn 16-38) 5% Damped Design Spectral Response Acceleration (1 see), S01 0.433g Section 1613.5.4 (Eqn 16-39) 1.2 - Conformance to the criteria for seismic design does not constitute any guarantee or assurance that significant structural damage or ground failure will not occur in the event of a maximum level earthquake. The primary goal of seismic design is to protect life and not to avoid all damage, since such design may be economically prohibitive. - Project No. G 1076-32-02 - 2 - December 23, 2013 2.0 Grading 2.1 Grading should be performed in accordance with the Recommended Grading Specifications in Appendix C. Where the recommendations of this report conflict with Appendix C, the recommendations of this section take precedence. 2.2 Earthwork should be observed and compacted fill tested by representatives of Geocon Incorporated. 2.3 A pre-construction conference with the city inspector, owner, contractor, civil engineer, and soil engineer in attendance should be held at the site prior to the beginning of grading operations. Special soil handling requirements can be discussed at that time. 2.4 Grading of the site, where planned, should commence with the removal of all existing vegetation and existing improvements from the areas to be graded, if any. Deleterious debris such as wood, asphalt, brick, and concrete should be exported from the site and should not be mixed with the fill soils, if present. All existing underground improvements within proposed structural areas should be removed and the resulting depressions properly backfilled in accordance with the procedures described herein. . if existing improvements are abandoned in-place, the suitability of the trench backfill should be evaluated or removed and re-compacted to at least 90 percent of the maximum dry density near to slightly over optimum moisture content as determined by ASTM Test Designation Dl 557. 2.5 Prior to placing fill, the ground surfaëe should be scarified to a depth of 12 inches, moisture conditioned, and compacted to a dry density of at least 90 percent of the laboratory maximum dry density near to slightly above optimum moisture content, as determined by ASTM Test Method D 1557. Deeper processing and/or removal may be necessary in areas where loose, wet or dry soils are encountered. 2.6 Excavated soils generated from the cut operations free of deleterious debris and/or contaminants can be placed and compacted in layers to the design finish grade elevations. All fill and backfill soils should be placed in horizontal loose layers with a maximum thickness of 8 inches, moisture conditioned to near optimum moisture content and compacted to a dry density of at least 90 percent of the laboratory maximum dry density as determined by ASTM Test Method D 1557. The upper 12 inches of fill beneath pavement should be moisture conditioned and compacted to a dry density of at least 95 percent of the maximum dry density at or slightly over optimum moisture content shortly before paving operations. Project No. G1076-32-02 -3 - December 23, 2013 I 2.7 Any import fill soil, if needed, should consist of granular materials with a "low" expansion potential (El less than 50) free of deleterious material or stones larger than 3 inches and compacted as recommended above. Geocon Incorporated should be notified of the import soil source so that laboratory testing can be performed to determine its suitability as fill material prior to its arrival at the site. 3.0 Foundations 3.1 The structures can be supported on a shallow foundation system founded entirely in Terrace Deposits. Foundations for the structures should consist of continuous strip footings and/or isolated spread footings. Continuous footings should beat least 12 inches wide and extend at least 24 inches below lowest adjacent pad grade. Isolated, spread footings should have a minimum width of 2 feet and should extend at least 24 inches below lowest adjacent pad grade. Steel reinforcement for continuous footings should consist of at least four No. 5 steel reinforcing bars placed horizontally in the footings, two near the top and two near the bottom. Steel reinforcement for the spread footings should' be designed by the project structural engineer. A footing dimension detail, depicting the depth to lowest adjacent grade, is presented in Figure 2. 3.2 Foundation excavations will require deepening through the undocumented fill to expose the Terrace Deposits. The approximate thickness of undocumented fill is' shown next to each boring location and generally ranges from 2 to 5 feet thick. The deepened excavations may be backfilled with a 2-sack cement slurry to bottom of planned footing elevation. 3.3 The minimum reinforcement recommended above is based on soil characteristics only (Expansion Index of 90 or less) and is not intended to replace reinforcement required for structural considerations. 3.4 The recommended allowable bearing capacity for foundations with minimum dimensions described above and bearing in Terrace Deposits is 3,000 pounds per square foot (psf). This allowable soil bearing pressure may be increased by an additional 400 psf for each additional foot of depth and 200 psf for each additional foot of width, to a maximum allowable bearing capacity of 6,000 psf. The values presented above are for dead plus live loads and may be increased by one-third when considering transient loads due to wind or seismic forces. - - Project No. G1076-32-02 -4- December 23, 2013 I 3.5 - Settlement due to footing loads conforming to the above recommended allowable soil I bearing pressures are expected to be less than 1-inch total and Y2-inch differential across the building. - 3.6 \\undation excavations should be observed by the geotechnical engineer (a representative of\ieocon Incorporated) prior to the placement of reinforcing steel and concrete to verify I that the exposed soil conditions are consistent with those anticipated and have been extended to appropriate bearing strata. If unanticipated soil conditions are encountered, foundation modifications may be required. I 4.0 Concrete Slabs-on-Grade • 4.1 Concrete slabs-on-grade for the structures should be at least 5 inches thick and reinforced No. 3 steel reinforcing bars at 18 inches on center in both horizontal directions. I with 4.2 Slabs that may receive moisture-sensitive floor coverings or may be used to store moisture- sensitive materials should be underlain by a vapor retarder. The vapor retarder design should be consistent with the guidelines presented in the American Concrete Institute's (ACI) Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials (ACl I 302.2R-06). In addition, the membrane should be installed in accordance with manufacturer's recommendations and ASTM requirements and installed in a manner that I prevents puncture. The vapor retarder used should be specified by the project architect or developer based on the type of floor covering that will be installed and if the structure will a humidity controlled environment. I possess 4.3 The bedding sand thickness should be determined by the project foundation engineer, I architect, and/or developer. However, we should be contacted to provide recommendations if the bedding sand is thicker than 6 inches. The foundation design engineer should provide appropriate concrete mix design criteria and curing measures to assure proper curing of the I slab by reducing the potential for rapid moisture loss and subsequent cracking and/or slab curl. We suggest that the foundation design engineer present the concrete mix design and proper curing methods on the foundation plans. It is critical that the foundation contractor I understands and follows the recommendations presented on the foundation plans. I 4.4 The concrete slab-on-grade recommendations are based on soil support characteristics only. The project structural engineer should evaluate the structural requirements of the concrete slabs for supporting vehicle, equipment and storage loads. I Project No. GI076-32-02 December 23, 2013 i '1 4.5 Exterior concrete flatwork not subject to vehicular traffic should be constructed in accordance with the recommendations herein. Slab panels should be a minimum of 4 inches thick and, when in excess of 8 feet square, should be reinforced with 6 x 6 - W2.9/W2.9 (6 x 6 - 6/6) welded wire mesh or No. 3 reinforcing bars at 18 inches on center in both directions to reduce the potential for cracking. in addition, concrete flatwork should be provided with crack control joints to reduce and/or control shrinkage cracking. Crack control spacing should be determined by the project structural engineer based upon the slab thickness and intended usage. Criteria of the American Concrete Institute (AC!) should be taken into consideration when establishing crack control spacing. Subgrade soil for exterior slabs not subjected to vehicle loads should be compacted in accordance with criteria presented in the grading- section prior to concrete placement: Subgrade soil should be properly compacted and the moisture content of subgrade soil should be checked prior to placing concrete. I 4.6 The recommendations presented herein are intended to reduce the potential for cracking of slabs and foundations as a result of differential movement. However, even with the incorporation of the recommendations presented herein, foundations and slabs-on-grade will still exhibit some cracking. The occurrence of concrete shrinkage cracks is independent of the soil supporting characteristics. Their occurrence may be reduced and/or controlled by limiting the slump of the concrete, the use of crack-control joints and proper concrete placement and curing. Literature provided by the Portland Concrete Association (PCA) and American Concrete Institute (ACl) present recommendations for proper concrete mix, construction and curing practices, and should be incorporated into project construction. I 5.0 Lateral Loading 5.1 To resist lateral loads, a passive pressure exerted by an equivalent fluid weight of 350 pounds per cubic foot (pci) should be used for design of footings or shear keys poured neat against compacted fill or formational materials. The upper 12 inches of material in areas not protected by floor slabs or pavement should not be included in design for passive u resistance. 5.2 If friction is to be used to resist lateral loads, an allowable coefficient of friction between I soil and concrete of 0.40 should be used for design for footings founded in compacted fill or formational materials. The recommended passive pressure may be used concurrently I with frictional resistance and may be increased by one-third for transient wind or seismic loading. - I - - Project No. G1076-32-02 - 6 - December 23, 2013 I - - I I 6.0 Retaining Walls 6.1 The structural engineer should determine the seismic design category for the project in accordance with Section 1613 of the.2010 CBC. If the project possesses a seismic design I category of D, E, or F, the proposed retaining walls should be designed with seismic lateral pressures. The seismic load exerted on the wall should be a triangular distribution with a pressure of 18H (where H is the height of the wall, in feet, resulting in pounds per square I foot [psfj) exerted at the base of the wall and zero at the top of the wall. We used a peak site acceleration of 0.35g calculated from Section 1803.5.12 of the 2010 California I Building Code (SD512.5) and applying a pseudo-static coefficient of 0.33. 6.2 Retaining walls not restrained at the top and having a level backfill surface should be I designed for an active soil pressure equivalent to the pressure exerted by a fluid density of 35 pcf: Where the backfill will be inclined at 2:1 (horizontal:vertical), an active soil pressure of 50 pcf is recommended. Expansive soils should not be used as backfill material behind retaining walls. All soil placed for retaining wall backfill should have an Expansion Index less than 50. 6.3 Unrestrained walls are those that are allowed to rotate more than 0.00IH (where H equals the height of the retaining portion of the wall) at the top of the wall. Where walls are restrained from movement at the top, an additional uniform pressure of 7H psf should be added to the above active soil pressure. For retaining walls subject to vehicular loads within a horizontal distance equal to two-thirds the wall height, a surcharge equivalent to 2 feet of fill soil should be added. 6.4 Retaining walls should be provided with a drainage system adequate to prevent the buildup of hydrostatic forces and waterproofed as required by the project architect. The use of drainage openings through the base of the wall (weep holes) is not recommended where the seepage could be a nuisance or otherwise adversely affect the property adjacent to the base of the wall. The above recommendations assume a properly compacted granular (El less than 50) free-draining backfill material with no hydrostatic forces or imposed surcharge load. Figure 3 presents a typical retaining wall drainage detail. If conditions different than those described are anticipated, or if specific drainage details are desired, Geocon Incorporated should be contacted for additional recommendations. 1 ProjectNo. G1076-32-02 -7- December 23. 2013 I 7.0 Storm Water Management 7.1 1f low-impact development (LID) integrated management practices (IMP's) are being considered, Geocon should review the design and provide specific geotechnical recommendations to reduce the potential adverse impacts to both on and off-site properties. 7.2 - If not property constructed, there is a potential for distress to improvements and properties located hydrologically down gradient or adjacent to these devices. Factors such as the amount of water to be detained, its residence time, and soil permeability have an important effect on seepage transmission and the potential adverse impacts that may occur if the storm water management features are not properly designed and constructed. We have not performed a hydrogeology study at the site. Down-gradient and adjacent properties may be subjected to seeps, springs, slope instability, raised groundwater, movement of foundations and slabs, or other impacts as a result of water infiltration. 7.3 Due to site soil and geologic conditions, and proximity to settlement sensitive improvements, a heavy duty, non-permeable liner, such as 30-mil pvc, or equivalent, should be placed beneath any hydro-modification areas where water infiltration into the underlying soils is planned. The strength and thickness of the membrane, and construction method should be adequate to assure that the liner will not be compromised throughout the life of the system. In addition, civil engineering provisions should be implemented to assure that the capacity of the system is never exceeded resulting in over topping or malfunctioning of the device. The system should also include a long-term maintenance program or periodic cleaning to prevent clogging of the filter media or drain envelope. Geocon Incorporated has no opinion regarding the design of the filtration system or its effectiveness. 8.0 Site Drainage and Moisture Protection 8.1 Adequate site drainage is critical to reduce the potential for differential soil movement, erosion and subsurface seepage. Under no circumstances should water be allowed to pond adjacent to footings. The site should be graded and maintained such that surface drainage is directed away from structures in accordance with 2010 CBC 1804.3 or other applicable standards. In addition, surface drainage should be directed away from the top of slopes into swales or other controlled drainage devices. Roof and pavement drainage should be directed into conduits that carry runoff away from the proposed structure. I Project No. G 1076-32-02 -8- December 23, 2013 I I I I I I I j I I P H I 8.2 Underground utilities should be leak free. Utility and irrigation lines should be checked periodically for leaks, and detected leaks should be repaired promptly. Detrimental soil movement could occur if water is allowed to infiltrate the soil for prolonged periods of time. 9.0 Grading and Foundation Plan Review 9.1 Geocon Incorporated should review the final grading and foundation plans for the project prior to final design submittal to evaluate whether additional analyses and/or recommendations are required. Should you have anyquestions regarding this correspondence or desire additional information, please contact the undersigned. - Very truly yours, GEOCON INCORPORATED Trevor . Myers RCE 63773 TEM:DBE:dmc:tmj (6) Addressee David B.Evans CEG 1860 %04AL 016, /DAVID 8, CERTIFIED ENGINEERING GEOLOGIST j OPC Project No. G1076-32-02 -9- December 23, 2013 WALL FOOTING CONCRETE SLAB l>< 4 4 A SAND PAD PAD GRADE / I MOISTURE INHIBITOR . .. (WHERE REQUIRED) . ...ç :• . i cc LL FOOTING* WIDTH COLUMN FOOTING CONCRETE SLAB I Ff111 lifT] SAND MOISTURE INHIBITOR 01 1 (WHERE REQUIRED) 4 4 4 4 u_ 4 . ........ ............-4' '..: - FOOTING WIDTH* *SEE REPORT FOR FOUNDATION WITDH AND DEPTH RECOMMENDATION NO SCALE I WALL / COLUMN FOOTING DIMENSION DETAIL I GEOCON INCORPORATED (low) GEOTECHNICAL • ENVIRONMENTAL • MATERIALS 6960 FLANDERS DRIVE -SAN DIEGO, CALIFORNIA 92121- 2974 PHONE 858 558-6900 - FAX 858 558-6159 TM I RS DSK/GTYPD )LFOOT2DWG 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA DATE 12-23-2013 1 PROJECT NO. G1076 -32-02 1 FIG. 2 ':\I*(0Jh1 I S\G 1O16-2-O2 5600 Avenida Encinas\OETAILS\COLFOOT2STB.clwg I. H I GEOCON I INCORPORATED 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA GEOTECHNICAL • ENVIRONMENTAL • MATERIALS 6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 91111, 2974 PHONE 858 558-6900 - FAX 858 558-6159 I TM RS DSK/GTYPD DATE 12-232013l PROJECT NO. G1076-32-02 FIG.3 - 7WDD7 - Y:\PROJECTS\G1076-32-02 5600 Avenida Encinas\0ETAILS\RWDD7.dwg I APPENDIX A EXPLORATORY BORING LOGS AND LABORATORY TEST RESULTS PERFORMED BY GEOCON INCORPORATED (2009) 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PROJECT NO. G1076-32-02 PROJECT NO. G1076-42-01 BORING B I z. >- DEPTH 0 < SOIL Z I— <I) ' uJ IN SAMPLE 9 CLASS ELEV. DATE z FEET NO. (MSL.)50' COMPLETED 02.03.2009 UJ EQUIPMENT IR-300 BY: N.N. BORJA 0 0 MATERIAL DESCRIPTION - ASPHALT CONCRETE 3 inches • \ BASE inches - SM - UNDOCUMENTED FILL Loose, moist, dark reddish brown, Silty, fine to medium SAND; trace gravel 2 B]-) -Becomes dense 43 — SM TERRACE DEPOSITS I; Dense, moist, mottled reddish brown and yellowish brown, Silty, fine to medium SAND - 131-2 :..f: - 38 6 B]3 II H :1 8 • :I -Becomes mottled reddish brown and light gray; trace mica - 10 ' .:1.':l. B]-4 :- 94 BI-5 12 T. - -Seepage at 13 feet .1. -Becomes wet, mottled yellowish brown and light gray - 14 BI-6 -i.. -IL 76 BORING TERMINATED AT 15 FEET Seepage encountered at 13 feet - Backfilled with cuttings Figure A-I, •_ Log of Boring B I, Page 1 of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL II ... STANDARD PENETRATION TEST I ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GEOCON PROJECT NO. G1076-42-01 - >- Of BORING B2 . zLu—. DEPTH SAMPLE SOIL I— Z <<0) 11) Z U uJ. z IN FEET NO. 0 CLASS ELEV. (MSL.)51' DATE COMPLETED 02-03-2009 wo 0 W o (USCS) (if EQUIPMENT IR-300 BY: N.N. BORJA yj Q 0 0 MATERIAL DESCRIPTION ASPHALT CONCRETE 2Y2 inches - - \ BASE 4inches SM UNDOCUMENTED FILL 132-1 .. Loose to medium dense, moist, dark reddish brown to dark brown. Silty, fine - 2 :1 to medium SAND; trace gravel - - - 132-2 :.LL 39 SM TERRACE DEPOSITS Dense, moist, mottled reddish brown and yellowish brown, Silty, fine to medium SAND; little mica flakes and manganese oxides; weathered - - B2-3 - 41 - 6 - B2-4 8 Becomes mottled reddish brown and light gray 10 B2-5 : 45 - B2-6 - 12 - - I Seepage at 13 feet 14 B2-7 :. -No recovery . 42 BORING TERMINATED AT 15 FEET - Seepage encountered at 13 feet Backfilled with cuttings Figure A-2, Log of Boring B 2, Page 1 of 1 SAMPLE SYMBOLS ... SAMPLING UNSUCCESSFUL 11 ... STANDARD PENETRATION TEST I ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GEOCON PROJECT NO. G1076-42-01 BORING DEPTH SAMPLE >. 9 < SOIL - I- z << 2W Lu (I) zu F- IN FEET NO. 0 CLASS ELEV. (MSL)53 DATE COMPLETED 02-03-2009 }- o 0 w o (USCS) - j EQUIPMENT IR-300 BY: N.N. BORJA Q 0 MATERIAL DESCRIPTION F. 91 ASPHALT CONCRETE 2Y2 inches \ BASE 4 Inches SM UNDOCUMENTED FILL II Medium dense to dense, moist, dark reddish brown to dark brown. Silty, fine 2 \ to medium SAND; trace gravel TtTTI - SM TERRACE DEPOSITS B3-1 50 • -: I Dense, damp to moist, mottled reddish brown and yellowish brown, Silty, fine I to medium SAND; some mica and manganese B3-2 - 4 - B3-3 - Li -Becomes very dense, mottled reddish brown and grayish brown to olive 69 I: brown 6 • 1:11:1 t.•IIi• 8 Ifi - 10 B3-4 -Becomes dense, very moist, grayish brown to brown 44 - B3-5 -Seepage at II feet 12 B3-6 i:. -No recovery 57 BORING TERMINATED AT 13 FEET Seepage encountered at 11 feet Baekfilled with bentonite chips and drill cuttings Figure A-3, Log of Boring B 3, Page 1 of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL II ... STANDARD PENETRATION TEST U ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE •.. WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. - - .• -. GEOCON PROJECT NO. G1076-42-01 BORING B 4 >-. 2o SAMPLE -J < SOIL I DEPTH F IL CO tr IN. NO. ELEV. (MSL.)53 DATE COMPLETED 02-03-2009 d FEET 0 (USCS) LIJ U) . . EQUIPMENT IR-300 BY: N.N. BORJA w. 0 MATERIAL DESCRIPTION ASPHALT CONCRETE 2V2 inches - - \ BASE 4inches SM - UNDOCUMENTED FILL Loose, moist, dark brown, Silty, fine to medium SAND; trace gravel - - 2 - B4-1 27 - B4-2 /7 CL TERRACE DEPOSITS - Firm to stiff, moist, dark grayish brown to olive brown, Sandy CLAY - - B4-3 - ---------------------------------24 ilL:-- — SM Medium dense, moist, grayish brown, Silty, fine to medium SAND BORING TERMINATED AT 5 FEET No groundwater encountered Backfilled with cuttings Figure A-4, Log of Boring B 4, Page 1 of 1 L ... SAMPLING UNSUCCESSFUL II ... STANDARD PENETRATION TEST ... DRIVE SAMPLE (UNDISTURBED) 1 SAMPLE SYMBOLS . I DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE . ... WATER TABLE OR SEEPAGE j NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GEOCON I , - PROJECT NO. G1076-42-01 BORINGB5- >- QOF. UJ DEPTH SAMPLE j SOIL I— Z IL <<0) (I) 2 of IN NO. 0 z CLASS ELEV. (MSL.)52' DATE COMPLETED 02-03-2009 DH H U) IL0 0 FEET D 0 (USCS) W U) >- - 0 2 of - EQUIPMENT IR-300 BY: N.N. BORJA L1J. CL MATERIAL DESCRIPTION ASPHALT CONCRETE 2V2 inches - - \ BASE 4inches - SM UNDOCUMENTED FILL Medium dense, moist, dark brown, Silty, fine to medium SAND; trace gravel 2 - BS-1 29 - - - CL TERRACE DEPOSITS Firm to stiff, moist, grayish brown to olive brown, Sandy CLAY -4- - - - B5-2 -Becomes hard - 57 6 B53 -8- - 10 - B5-4 - 48 :1T SM Dense, damp to moist, light gray to grayish brown, Silty, floe to medium - - B5-5 SAND; some mica and manganese - - 12 - 14 - B5-6 1 I -Becomes very moist, fine- to coarse-grained - 56 BORING TERMINATED AT 15 FEET No groundwater encountered Backfilled with bentonite chips and drill cuttings I Figure A-5, Log of Boring B 5, Page 1 of I I SAMPLE SYMBOLS ... SAMPLING UNSUCCESSFUL Ii... STANDARD PENETRATION TEST DRIVE SAMPLE (UNDISTURBED) - ... DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE ... WATER TABLE OR SEEPAGE I NOTE THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. - GEOCON PROJECT NO. G1076-42-01 af BORING ,- DEPTH > < SOIL . H z IL I— CO IN SAMPLE NO. o 2: 0 z ELEV. CLASS (MSL.)_51 DATE COMPLETED 02-03-2009 I U) Z I— FEET i— J 0 (USCS) . z U) >- 0 z IX EQUIPMENT IR-300 BY: N.N. BORJA w. - MATERIAL DESCRIPTION - 0 - - ASPHALT CONCRETE 21/2 inches \ BASE 4inches I SM - UNDOCUMENTED FILL Loose to medium dense, moist, dark brown, Silty, fine to medium SAND; - 2 - trace gravel - 136-I 34 - B6-2 SM TERRACE DEPOSITS Dense, moist, dark reddish brown to brown, Silty, fine to medium SAND - 4 - - B6-3 1 -Becomes medium dense - 22 - 6 - - 8 F :L -Becomes dense, damp to moist, yellowish brown to reddish brown; some 10 - B64 jj-•I• — mica and manganese - 31 BORING TERMINATED AT 10¼ FEET No groundwater encountered Backfilled with drill cuttings Figure A-6, Log of Boring B 6, Page 1 of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL III ... STANDARD PENETRATION TEST U ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. - . GEOCON APPENDIX B LABORATORY TESTING We performed laboratory tests in accordance with generally accepted test methods of the American Society for Testing and Materials (ASTM) or other suggested procedures. Selected samples were tested to evaluate compaction (maximum dry density and optimum moisture content), expansion characteristics, direct shear strength, and water-soluble sulfate content. The results of the laboratory tests are summarized in Tables B-I through B-IV. TABLE B-I SUMMARY OF LABORATORY MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT TEST RESULTS ASTM D 1557-02 Sample Description Maximum Dry Optimum Moisture No. Density (pci) Content (% dry wt.) 132-1 Dark brown, Silty, fine to coarse SAND; trace gravel 134.9 8.2 B3-2 I Yellowish brown, Silty, fine to medium SAND 134.3 7.8 TABLE B-Il SUMMARY OF LABORATORY DIRECT SHEAR TEST RESULTS ASTM D 3080-03 Sample No. Dry Density (pci) Moisture Content (%) Unit Cohesion (psi) (degrees) Angle of Shear Resistance Initial Final B3-1 - 113.2 6.8 •. 13.8 1 180 1 38 TABLE B-Ill SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS ASTM D 4829-03 Sample No. Moisture Content (%) Dry Density (pci) Expansion Index Before Test After Test B2-1 7.5 12.4 119.1 2 B5-3 1 9.1 J 22.6 1 111.1 88 Project No. G1076-42-01 - 81 - February 24, 2009 TABLE B-IV SUMMARY OF LABORATORY WATER-SOLUBLE SULFATE TEST RESULTS CALIFORNIA TEST NO. 3417 Sample No. Water-Soluble Sulfate (% SO4) Sulfate Exposure 132-1 0.038 Negligible 135-3 0.005 Negligible I I I I I Project No. C 1076-42-01 - 8-2 - February 24, 2009 I I I I I I I APPENDIX B I EXPLORATORY BORING LOGS AND LABORATORY TEST RESULTS PERFORMED BY LEIGHTON &ASSOCIATES (2001) I FOR 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA I PROJECT NO. G1076-32-02 I I I I I I I GEOTECHNICAL BORING LOG KEY Dale Sheet 1 of _L. Project KEY TO BORING LOG GRAPHICS Project No. Drilling Co. Type of Rig Hole Diameter Drive Weight Drop Elevation lop of Hole +1- ft. Ref. or Datum i > W . OJI 0 . € . 19 D 9f 31 C (3 5d j CI)'" GEOTECHMCAL DESCRIPTION Logged By Sampled By 0— - - - - - - iT Inorganic clay of low to medium plasticity: gravelly clay; sandy clay; silty clay; lean cla- ' CH Inorganic clay or high plasticity: fat clay . OL-OH Organic clay, silt or silty clay-clayey silt mixtures - SFr ML Inorganic silt; very fine sand: silty or-clayey fine sand, clayey silt with low plasticity MH Inorganic silt; diatomaccous fine sandy or silty soils; elastic silt - - I CAL SAMP E CL-ML Low plasticity clay to silt mixture : ML-SM sandy silt to silty sand mixture - Sandy clay to clayey sand mixture SC-SM Clayey sand to silty sand mixture - E . to SW Well graded sand; gravelly sand, little or no fines .•: SP Poorly graded sand; gravelly sand, little or no fines - Silty sand; poorly graded sand-silt mixture - : SC Clayey sand: poorly graded sand; clay mixture - . 0• OW Well graded gravel; gravel-rand mixture, little or no fines tz GP Poorly graded gravel; gravel-sand mixture. little or no fines 15— GR( L TAI ND WA &EAT' TER f - 0 DRIIJ 4G GM Silty gravel; gravel-sand-silt mixture Clayey gravel; gravel-sand-clay mixture -. Sandstone Siltstone - Claystone 20 — P - oT Breccia (angular gravel and cobbles or matrix-support conglomerate) Conglomerate (rounded gravel and cobble class-supported) - - Igneous granitic or granitic type rock - Mctavolcanic or metamorphic rock Artificial or man-made fill 25— Asphaltic concrete Portland cement concrete 505A(11/77) LEIGHTON & ASSOCIATES GEOTECUNICAL BORING LOG B-i Date 3-7-01 Sheet _...L. of _.L... Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 81n Drive Weight 140 pounds Drop 30, in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level - °"a. W C.) ," j (n'"' GEOTECHNICAL DESCRIPTION Logged By AXT Sampled By AXT Bag-i - - - @0': 4' Asphalt Concrete over 5' Base @0-5 SM ARTIFICIAL FILL - S 2': Silty fine SAND: dark brown to brown, moist, medium dense; contact with 1 17 Terrace Deposits ©3' ---------------------------- SM TERRACE DEPOSITS 45- 5-1 2 44 110.6 13.0 SM-SC @5': Silty fine to medium SAND: red-brown to brown, moist, medium dense; slightly cemented; slightly clayey 40 10 3 50 SM-SC @ 10': Silty fine to medium SAND: dark brown, moist, medium dense; slightly -:2 clayey - - : : •: @ 13': Ground water encountered 35 15 : 4 55 105.0 20.4 SW © 15': Well-graded fine to coarse SAND: brown, wet, medium dense; 2-1/2" rounded gravel in shoe -: SW SAN'llAOOFORIAATION 30 20—'. 5 95 SM @20': Silty fine to coarse SAND: grayish-brown, moist to wet, medium dense 25 25 : •. : 6 1 5014" 120.2 12.4 SM @25': Silty fine to coarse SANDSTONE: grayish-brown, moist, very dense; - : :. :• . moderately cemented 505A(11/77) I LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-i Date 3-7-01 . Sheet 2 of 2 Project Carltas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds Drop 307in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level - GEOTECHNICAL DESCRIPTION fa . 0A .gt . w ; 2 O Logged By AXT W a, Sampled By AXT 20 30— flI 30': Same as previous Total Depth = 30.4 Feet - Ground water encountered at 13 feet - Backfiflcd with cuttings, bcntonite, and concrete on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 15 35- 10 40- 5 45- 0 50- -5 - 55- ff) - = 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-2 Date 3-7-01 Sheet 1 of 1 Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds Drop jj in. Elevation Top of Hole +1- 48 ft. Ref. or Datum Mean Sea Level C .2 4- GEOTECHNICAL DESCRIPTION i;i; t.' € ! 'uU >' '°' . Z tL L D' n" ....G Logged By AXT W D C.) j U) Sampled By AXT - 0 . - 1118-2 - - - @0-4': Asphalt Concrete -- '_4-(gg!teBs - - - - - - - - - - - - - - - - - - - - - - - - - I-il SM ARTIFICIAL FILL - 8: Silty fine to coarse SAND: grey-brown, dry, medium dense; possibly ' .d 7 decoersoaed gnite 45 - 1 28 112.4 13.0 CH RESIDUAL SOIL slightly organic 2 28 SM-SC TERRACE DEPOSITS -: @ 5': Silty fine to medium SAND: reddish-brown to gray-brown, moist, medium - : dense; slightly clayey 40 3 39 97.7 —-- 8.6 SF @ 10': Poorly-graded fine SAND: brown, moist, medium dense; slightly silty - 13— :...:.E. 4 44 SF l IS': Same as previous; dense 30-. :: A1f SANT1AGOFORMAT1ON 20— j 77 0 20': Silty fine SAND: reddish-brown to grayish-green, very dense; slightly - -/: oxidized; slightly clayey 25- 25 -:•:•: - 6 64/6' - @25': Well-graded medium to coarse SAND: light brown, moist, very dense, - \ moderately cemented Total Depth 25.5 Feet - Ground water encountered at 14 feet at time of drilling Backfilled with soil cuttings on 3/7/01 Capped with 2 to 3 inches asphalt concrete 20 - - - - - = 5Q5A(1/.77) LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-3 Date 3-7-01 Sheet IThf 1 Project Carltas/Carisbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds —Drop .... in. levation Too of Hole +1- 47 ft. Ref. or Datum Mean Sea Level GEOTECHNICAL DESCRIPTION i tW € >@ O)W C2— IL..1 . 0 OIL - L • a. ...Gi Logged By AXT LU C,, j Sampled By AXT 0 - Bag-3 - - - @ 0-3.5': Asphalt Concrete :. °'' - SM ARTIFICIAL FILL - .@7': —Silty fine SAND: brown, moist - 1 37 1165 149 SM SC - TERRACE DEPOSaS gray brown to red brown and white moist medium dense; calcium carbonate blebs visible 2 2 22 SM © 5': Silty fine SAND: grayish-brown. moist, medium dense 10— 3 78 120.9 15.0 @ 10: Same as previous; dense 35 - 15 H 4 77 © 15': Silty fine to medium SAND: reddish-brown to gray, moist to wet, very - dense; 1/4' to 1/2' subangular gravels common 30 - 20— 5 73 SM SANTIAGOFORMATION © 20': Silty fine to SAND: brown to greenish-brown, moist, very dense; few fine - gravels; moderately cemented 2.5 - Total Depth 2t.5Feet Ground Water encountered at 14 feet at time of drilling Backlilled with soil cuttings on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 25- 20- in- 505A(11/77). LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-4 Date 3-7-01 Sheet I of I Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig 8-61 Hole Diameter 8 in Drive Weight 140 pounds Drop .30 in. Elevation Too of Hole +1- 47 ft. Ref. or Datum Mean Sea Level 31 GEOTECHNICAL DESCRIPTION .i . .! - t 4-5 . (tit z Logged By AXT UI In 0 LI (' Sampled By AXT Bag4 - - - ® 0-3": Asphalt Concrete M @3"67:AggregatcBaSe 45--:4'1 ARTIFICIAL FILL E ht brown, moist M , TERRACE DEPOSITS 1 47 116.8 15.9 SM-SC @ 5': Silty clayey fine SAND: red-brown to gray-brown, moist, medium dense; - ol / calcium carbonate blebs visible 40- 10— 2 31 SM-SC @ 10': Silty fine SAND: gray-brown, moist, medium dense; slightly clayey 35 - 3 58 107.8 20,4 SP @ 15'; Poorly-graded fine to medium SAND: grayish brown, moist to wet, medium dense; thin beds of medium to coarse SAND; slightly micaceous: slightly silty 30 - 20— :' 4 70/6" SP SANyAGOFORMATION—- - - - - _ \ 20: Silty fine SAND: light grayish brown, moist, very dense; moderately cemented 25 - Total Depth = 20.5 Fees Ground water encountered at 16 feet at time of drilling Backflhled with soil cuttings on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 25- 20 -- - n— 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-S Date 3-7-01 Sheet 1 of I Project Caritas/Carisbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level 31 GEOTECHNICAL DESCRIPTION Logged By AXT W (I) 0 c) (1' Sampled By AXT 50 0— — — — © 0-3.5: Asphalt Concrete - ',• @0'-5' — — — — • SF ARTIFICIAL FILL - - - - @ 8.5': Silty fine SAND: brown. moist SF TERRACE DEPOSITS I 29 106.2 5.5 0 5': Poorly-graded fine SAND: red-brown to brown, moist, medium dense; slightly silly 40 10— : 2 32 SF @ 10': Poorly-graded fine SAND; gray to orange, moist, dense; slightly oxidized 35 15— : 3 80110' 112.2 17.4 SW © 15': Will-graded fine to coarse SAND: light brown, wet, very dense 30 20—:::'*"* , 4 97 1C SANTIAGO FORMATION - - - - @ 21': SILTSTONE: grayish brown, dry to slightly moist, very stiff Total Depth = 21.5 Feel - Ground water encountered at 14.5 feet at time of drilling - Backuilted with soil cuttings on 3/7/01 - Capped w1th2 to 3 inches asphalt concrete 25 2LL 25- ii)— 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHMCAL BORING LOG B-6 Date 3-7-01 Sheet 1 of 1 Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter gin DriveWeight 140 pounds I Drop jLin. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level u GEOTECHNICAL DESCRIPTION '0.i i•In . Z . . W Logged By AXT W u j 0 (0" Sampled By AXT 50 0— - - - - - t 0-2.5w: Asphalt Concrete - 2,56Y_AJ&reJateBase SM ARTIFICIAL FILL - : @ 6.5': Silty tine SAND: Mottled dark brown to brown, moist, medium dense I 40 120.4 12.8 -I SP TERRACE DEPOSITS @ 5.5': Contact with Terrace Deposits - ..:. @6': Poorly-graded fine SAND: reddish-brown, moist, medium dense 40 2 27 SP @ 10': Same as previous 35 IS 3 80 110.7 20.4 SP © 15': Poorly-graded fine to medium SAND: brown, wet, dense; slightly silty 104.6 20.2 SZ 30 20-'.-'-''_.;. 5 70/tO' SW NTIAGOFORJa4ATION - @20': Well-graded fine to coarse SAND: light brown, wet, very dense - Total Depth 21.5 Feet Ground water encountered at 17 feet at time of drilling - Backfllled with soil cuttings on 317101 - Capped with 2 to 3 inches asphalt concrete 25 _2 25— fl— 505A(11/77) LEIGHTON & ASSOCIATES 040382-001 APPENDIX C Laboratory Testing Procedures and Test Results Chloride Content: Chloride content was tested in accordance with DOT Test Method No. 422. The results are presented below: Sample Location ( Chloride Content, ppm Chloride Attack Potential* B-I, 0-5 Feet 170 Threshold B-3, 0-5 Feet 350 Positive per City of San Diego Program Guidelines for Design Consultant, 1992. Consolidation Tests: Consolidation tests were performed on selected, relatively undisturbed ring samples in accordance with Modified ASTM Test Method D2435. Samples were placed in a consolidometer and loads were applied in geometric progression. The percent consolidation for each load cycle was recorded as the ratio of the amount of vertical compression to the original I-inch height. The consolidation pressure curves are presented on the attached figure. Direct Shear Tests: Direct shear tests were performed on selected remolded and/or undisturbed samples which were soaked for a minimum of 24 hours under a surcharge equal to the applied normal force during testing. After transfer of the sample to the shear box and reloading of the sample, the pore pressures set up in the sample (due to the transfer) were allowed to dissipate for a period of approximately 1 hour prior to application of shearing force. The samples were tested under various normal loads utilizing a motor-driven, strain-controlled, direct-shear testing apparatus at a strain rate of less than 0.001 to 0.5 inches per minute (depending upon the soil type). After a "peak" value of shear strength was observed or after a shear strength was observed or after a shear strain of 0.2 inches if no peak was observed, the motor was stopped and the sample was allowed to "relax" for approximately 15 minutes. The stress drop during the relaxation period was recorded. It is anticipated that, in a majority of samples tested, the 15 minutes relaxing of the samples is sufficient to allow dissipation of pore pressures that may have set up in the samples due to shearing. The drained peak strength was estimated by deducting the shear force reduction during the relaxation period from the peak shear values. The shear values at the end of shearing are 'ultimate" values. The drained peak strengths are presented in the test data. Friction Angle Apparent Sample Location Sample Description Test Type (degrees) Cohesion (psi) B-2, 11 Feet Brown poorly-graded fine sand Undisturbed 33 140 B-4,6 Feet Red-brown to gray-brown silty Undisturbed 30 1020 clayey sand I] I C.' 1], I I 040382-001 APPENDIX C (continued) Hydrocollapse: Selected samples were loaded in a consolidometer to the proposed overburden pressure. The samples were then inundated with water and the percent hydrocollapse was measured and recorded below. tB ple Location % 1-lydrocollapse -6, 6 Feet I 0.2 @700 psf Expansion Index Tests: The expansion potential of selected materials was evaluated by the Expansion Index Test, U.B.C. Standard No. 18-2. Specimens are molded under a given compactive energy to approximately the optimum moisture content and approximately 50 percent saturation or approximately 90 percent relative compaction. The prepared 1-inch thick by 4-inch diameter specimens are loaded to an equivalent 144 psf surcharge and are inundated with tap water until volumetric equilibrium is reached. The results of these tests are presented in the table below: Compacted Dry Expansion Expansion Sample Location Sample Description Density (pcf) Index Potential B-i, 0-5 Feet Brown silty sand 120.8 2 Very Low B-3, 0-5 Feet Gray brown silty clayey 114.4 56 Medium sand Moisture and Density Determination Tests: Moisture content and dry density determinations were performed on relatively undisturbed samples obtained from the test borings. The results of these tests are presented in the boring logs. Where applicable, only moisture content was determined from 'undisturbed" or disturbed samples. Minimum Resistivity and pH Tests: Minimum resistivity and p1-I tests were performed in general accordance with California Test Method 643. The results are presented in the table below: Sample Sample Location Description pH Minimum Resistivity (ohms-cm) B-I, 0-5 Feet Brown silty sand 7.2 4600 B-3, 0-5 Feet Gray brown silty clayey 8.0 890 sand C-2 APPENDIX C (continued) Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard geochemical methods. The test results are presented in the table below: Sample Location Sulfate Content (%) Potential Degree of Sulfate Attack* B-I, 0-5 Feet 0.018 Negligible B-3, 0-5 Feet 0.020 Negligible * Based on the 1997 edition of the Uniform Building Code, Table No. 19-A-4, prepared by the International Conference of Building Officials (ICBO, 1997). 'R"-Value: The resistance "R"-value was determined by the California Materials Method No. 301 for base, subbase, and basement soils. The samples were prepared and exudation pressure and "R"-value determined. The graphically determined "R"-value at exudation pressure of 300 psi is reported. - Location Design R-Value B-3, 0-5 Feet 21 C.3 APPENDIX APPENDIX C RECOMMENDED GRADING SPECIFICATIONS FOR 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PROJECT NO. G1076-32-02 RECOMMENDED GRADING SPECIFICATIONS 1. GENERAL 1.1 These Recommended Grading Specifications shall, be used in conjunction with the Geotechnical Report for the project prepared by Geocon Incorporated. The recommendations contained in the text of the Geotechnical Report are a part of the earthwork and grading specifications and shall supersede the provisions contained hereinafter in the case of conflict. 1.2 Prior to the commencement of grading, a geotechnical consultant (Consultant) shall be employed for the purpose of observing earthwork procedures and testing the fills for substantial conformance with the recommendations of the Geotechnical RepOrt and these specifications. The Consultant should provide adequate testing and observation services so that they may assess whether, in their opinion, the work was performed in substantial conformance with these specifications. It shall be the responsibility of the Contractor to assist the Consultant and keep them apprised of work schedules and changes so that personnel may be scheduled accordingly. 1.3 It shall be the sole responsibility of the Contractor to provide adequate equipment and methods to accomplish the work in accordance with applicable grading codes or agency ordinances, these specifications and the approved grading plans. If, in the opinion of the Consultant, unsatisfactory conditions such as questionable soil materials, poor moisture condition, inadequate compaction, adverse weather, result in a quality of work not in conformance with these specifications, the Consultant will be empowered to reject the work and recommend to the Owner that grading be stopped until the unacceptable Li conditions are corrected. 2. DEFINITIONS 2.1 Owner shall refer to the owner of the property or the entity on whose behalf the grading work is being performed and who has contracted with the Contractor to have grading performed. 2.2 Contractor shall refer to the Contractor performing the site grading work. 2.3 Civil Engineer or Engineer of Work shall refer to the California licensed Civil Engineer or consulting firm responsible for preparation of the grading plans, surveying and verifying as-graded topography. GI rev. 07/2013 2.4 Consultant shall refer to the soil engineering and engineering geology consulting firm retained to provide geotechnical services for the project. 2.5 Soil Engineer shall refer to a California licensed Civil Engineer retained by the Owner, who is experienced in the practice of geotechnical engineering. The Soil Engineer shall be responsible for having qualified representatives on-site to observe and test the Contractor's work for conformance with these specifications. 2.6 Engineering Geologist shall refer to a California licensed Engineering Geologist retained by the Owner to provide geologic observations and recommendations during the site grading. 2.7 Geotechnical Report shall refer to a soil report (including all addenda) which may include a geologic reconnaissance or geologic investigation that was prepared specifically for the development of the project for which these Recommended Grading Specifications are intended to apply. 3. MATERIALS 3.1 Materials for compacted fill shall consist of any soil excavated from the cut areas or imported to the site that, in the opinion of the Consultant, is suitable for use in construction of fills. In general, fill materials can be classified as soil fills, soil-rock fills or rock fills, as defined below. 3.1.1 Soil fills are defined as fills containing no rocks or hard lumps greater than 12 inches in maximum dimension and containing at least 40 percent by weight of material smaller than 3/4 inch in size. 3.1.2 Soil-rock fills are defined as fills containing no rocks or hard lumps larger than 4 feet in maximum dimension and containing a sufficient matrix of soil fill to allow for proper compaction of soil fill around the rock fragments or hard lumps as specified in Paragraph 6.2. Oversize rock is defined as material greater than 12 inches. 3.1.3 Rock fills are defined as fills containing no rocks or hard lumps larger than 3 feet in maximum dimension and containing little or no fines. Fines are defined as material smaller than 1/4 inch in maximum dimension. The quantity of fines shall be less than approximately 20 percent of the rock fill quantity. GI rev. 07/2013 I I I H P [.1 I H' 3.2 Material of a perishable, spongy, or otherwise unsuitable nature as determined by the Consultant shall not be used in fills. 3.3 Materials used for fill, either imported or on-site, shall not contain hazardous materials as defined by the California Code of Regulations, Title 22, Division 4, Chapter 30, Articles 9 and 10; 40CFR; and any other applicable local, state or federal laws. The Consultant shall not be responsible for the identification or analysis of the potential presence of hazardous materials. However, if observations, odors or soil discoloration cause Consultant to suspect the presence of hazardous materials, the consultant may request from the Owner the termination of grading operations within the affected area. Prior to resuming grading operations, the Owner shall provide a written report to the Consultant indicating that the suspected materials are not hazardous as defined by applicable laws and regulations. 3.4 The outer 15 feet of soil-rock fill slopes, measured horizontally, should be composed of properly compacted soil fill materials approved by the Consultant. Rock fill may extend to the slope face, provided that the slope is not steeper than 2:1 (horizontal:vertical) and a soil layer no thicker than 12 inches is track-walked onto the face for landscaping purposes. This procedure may be utilized provided it is acceptable to the governing agency, Owner and Consultant. 3.5 Samples of soil materials to be used for fill should be tested in the laboratory by the Consultant to determine the maximum density, optimum moisture content, and, where appropriate, shear strength, expansion, and gradation characteristics of the soil. 3.6 During grading, soil or groundwater conditions other than those identified in the Geotechnical Report may be encountered by the Contractor. The Consultant shall be notified immediately to evaluate the significance of the unanticipated condition 4. CLEARING AND PREPARING AREAS TO BE FILLED 4.1 Areas to be excavated and filled shall be cleared and grubbed. Clearing shall consist of complete removal above the ground surface of trees, stumps, brush, vegetation, man-made structures, and similar debris. Grubbing shall consist of removal of stumps, roots, buried logs and other unsuitable material and shall be performed in areas to be graded. Roots and other projections exceeding I l/2 inches in diameter shall be removed to a depth of 3 feet below the surface of the ground. Borrow areas shall be grubbed to the extent necessary to provide suitable fill materials. Gi rev. 07/2013 P H I I I I 4.2 Any asphalt pavement material removed during clearing operations should be properly disposed at an approved off-site facility. Concrete fragments that are free of reinforcing steel may be placed in fills, provided they are placed in accordance with Section 6.2 or 6.3 of this document. 4.3 After clearing and grubbing of organic matter and other unsuitable material, loose or porous soils shall be removed to the depth recommended in the Geotechnical Report. The depth of removal and compaction should be observed and approved by a representative of - the Consultant. The exposed surface shall then be plowed or scarified to a minimum depth of 6 inches and until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment to be used. 4.4 Where the slope ratio of the original ground is steeper than 5:1 (horizontal:vertical), or where recommended by the Consultant, the original ground should be benched in accordance with the following illustration. TYPICAL BENCHING DETAIL Finish Grade Remove All Unsuitable Material As Recommended By Consultant Slope To Be Such That Sloughing Or Sliding Does Not Occur Varies ; -Original Ground F Finish Slope Surface See Note 1 Se No Scale DETAIL NOTES: (1) Key width "B" should be a minimum of 10 feet, or sufficiently wide to permit complete coverage with the compaction equipmentused. The base of the key should be graded horizontal, or inclined slightly into the natural slope. (2) The outside of the key should be below the topsoil or unsuitable surficial material and at least 2 feet into dense formational material. Where hard rock is exposed in the bottom of the key, the depth and configuration of the key may be modified as approved by the Consultant. GI rev. 07/2013 4.5 After areas to receive fill have been cleared and scarified, the surface should be moisture conditioned to achieve the, proper moisture content, and compacted as recommended in Section 6 of these specifications. 5. COMPACTION EQUIPMENT 5.1 Compaction of soil or soil-rock fill shall be accomplished by sheepsfoot or segmented-steel wheeled rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers, or other types of acceptable compaction equipment. Equipment shall be of such a design that it will be capable of compacting the soil or soil-rock fill to the specified relative compaction at the specified moisture content. 5.2 Compaction of rock fills shall be performed in accordance with Section 6.3. 6. PLACING, SPREADING AND COMPACTION OF FILL MATERIAL 6.1 Soil fill, as defined in Paragraph 3.1.1, shall be placed by the Contractor in accordance with the following recommendations: 6.1.1 Soil fill shall be placed by the Contractor in layers that, when compacted, should generally not exceed 8 inches. Each layer shall be spread evenly and shall be thoroughly mixed during spreading to obtain uniformity of material and moisture in each layer. The entire fill shall be constructed as a unit in nearly level lifts. Rock materials greater than 12 inches in maximum dimension shall be placed in accordance with Section 6.2 or 6.3 of these specifications. 6.1.2 In general, the soil fill shall be compacted at a moisture content at or above the optimum moisture content asdetermined by ASTM D 1557-09. 6.1.3 When the moisture content of soil fill is below that specified by the Consultant, water shall be added by the Contractor until the moisture content is in the range specified. 6.1 .4 When the moisture content of the soil fill is above the range specified by the Consultant or too wet to achieve proper compaction, the soil fill shall be aerated by, the Contractor by blading/mixing, or other satisfactory methods until the moisture content is within the range specified. GI rev. 07/2013 I I I I I I I I I I I I I I I I I I I 6.1.5 After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted by the Contractor to a relative compaction of at least 90 percent. U Relative compaction is defined as the ratio (expressed in percent) of the in-place dry density of the compacted fill to the maximum laboratory dry density as determined in accordance with ASTM D 1557-09. Compaction shall be continuous over the entire area, and compaction equipment shall make sufficient passes so that the specified minimum relative compaction has been achieved throughout the I entire fill. 6.1 .6 Where practical, soils having an Expansion Index greater than 50 should be placed at least 3 feet below finish pad grade and should be compacted at a moisture content generally 2 to 4 percent greater than the optimum moisture content for the I material. 6.1 .7 Properly compacted soil fill shall extend to the design surface of fill slopes. To achieve proper compaction, it is recommended that fill slopes be over-built by at least 3 feet and then cut to the design grade. This procedure is considered preferable to track-walking of slopes, as described in the following paragraph. 6.1 .8 As an alternative to over-building of slopes, slope faces may be back-rolled with a heavy-duty loaded sheepsfoot or vibratory roller at maximum 4-foot fill height intervals. Upon completion, slopes should then be track-walked with a D-8 dozer I . or similar equipment, such that a dozer track covers all slope surfaces at least twice. 6.2 Soil-rock fill, as defined in Paragraph 3.1.2, shall be placed by the Contractor in accordance with the following recommendations: 6.2.1 Rocks larger than 12 inches but less than 4 feet in maximum dimension may be incorporated into the compacted soil fill, but shall be limited to the area measured - 15 feet minimum horizontally from the slope face and 5 feet below finish grade or 3 feet below the deepest utility, whichever is deeper. 6.2.2 Rocks or rock fragments up to 4 feet in maximum dimension may either be individually placed or placed in windrows. Under certain conditions, rocks or rock fragments up to 10 feet in maximum dimension may be placed using similar methods. The acceptability of placing rock materials greater than 4 feet in maximum dimension shall be evaluated during grading as specific cases arise and shall be approved by the Consultant prior to placement. GI rev. 07/2013 I I 6.2.3 For individual placement, sufficient space shall be provided between rocks to allow for passage of compaction equipment. — 6.2.4 For windrow placement, the rocks shoild be placed in trenches excavated in properly compacted soil fill. Trenches should be approximately 5 feet wide and I 4 feet deep in maximum dimension. The voids around and beneath rocks should be filled with approved granular soil having a Sand Equivalent of 30 or greater and I should be compacted by flooding. Windrows may also be placed utilizing an "open-face" method in lieu of the trench procedure, however, this method should - first be approved by the Consultant. 6.2.5 Windrows should generally be parallel to each other and maybe placed either I parallel to or perpendicular to the face of the slope depending on the site geometry. The minimum horizontal spacing for windrows shall be 12 feet center-to-center with a 5-foot stagger or offset from lower courses to next overlying course. The I minimum vertical spacing between windrow courses shall be 2 feet from the top of a lower windrow to the bottom of the next higher windrow. 6.2.6 Rock placement, fill placement and flooding of approved granular soil in the I windrows should be continuously observed by the Consultant. 6.3 Rock fills, as defined in Section 3.1.3, shall be placed by the Contractor in accordance with the following recommendations: I 6.3.1 The base of the rock fill shall be placed on a sloping surface (minimum slope of 2 I percent). The surface shall slope toward suitable subdrainage outlet facilities. The rock fills shall be provided with subdrains during construction so that a hydrostatic I pressure buildup does not develop. The subdrains shall be permanently connected - to controlled drainage facilities to control post-construction infiltration of water. I 6.3.2 Rock fills shall be placed in lifts not exceeding 3 feet. Placement shall be by rock trucks traversing previously placed lifts and dumping at the edge of the currently I placed lift. Spreading of the rock fill shall be by dozer to facilitate seating of the rock. The rock fill shall be watered heavily during placement. Watering shall consist of water trucks traversing in front of the current rock lift face and spraying I water continuously during rock placement. Compaction equipment with compactive energy comparable to or greater than that of a 20-ton steel vibratory roller or other compaction equipment providing suitable energy to achieve the 1 GI rev. 07/2013 1 required compaction or deflection as recommended in Paragraph 6.3.3 shall be • - utilized. The number of passes to be made should be determined as described in I Paragraph 6.3.3. Once a rock fill lift has been covered with soil fill, no additional rock fill lifts will be permitted over the soil fill. 6.3.3 Plate bearing tests, in accordance with ASTM D 1196-09, may be performed in both the compacted soil fill and in the rock fill to aid in determining the required I minimum number of passes of the compaction equipment. If performed, a minimum of three plate bearing tests should be performed in the properly compacted soil fill (minimum relative compaction of 90 percent). Plate bearing tests shall then be performed on areas of rock fill having two passes, four passes and six passes of the compaction equipment, respectively. The number of passes I required for the rock fill shall be determined by comparing the results of the plate bearing tests for the soil fill and the rock fill and by evaluating the deflection variation with number of passes. The required number of passes of the compaction I equipment will be performed as necessary until the plate bearing deflections are equal to or less than that determined for the properly compacted soil fill. In no case will the required number of passes be less than two. 6.3.4 A representative of the Consultant should be present during rock fill operations to I observe that the minimum number of "passes" have been obtained, that water is being properly applied and that specified procedures are being followed. The actual number of plate bearing tests will be determined by the Consultant during grading. 6.3.5 Test pits shall be excavated by the Contractor so that the Consultant can state that, in their opinion, sufficient water is present and that voids between large rocks are properly filled with smaller rock material. In-place density testing will not be required in the rock fills. 6.3.6 To reduce the potential for "piping" of fines into the rock fill from overlying soil fill material, a 2-foot layer of graded filter material shall be placed above the uppermost lift of rock fill. The need to place graded filter material below the rock should be determined by the Consultant prior to commencing grading. The gradation of the graded filter material will be determined at the time the rock fill is being excavated. Materials typical of the rock fill should be submitted to the I Consultant in a timely manner, to allow design of the graded filter prior to the commencement of rock fill placement. I - 6.3.7 Rock fill placement should be continuously observed during placement by the Consultant. 1 - GI rev. 07/2013 I 7. OBSERVATION AND TESTING I 7.1 The Consultant shall be the Owner's representative to observe and perform tests during clearing, grubbing, filling, and compaction operations. In general, no more than 2 feet in vertical elevation of soil or soil-rock fill should be placed without at least one field density test being performed within that interval. In addition, a minimum of one field density test should be performed for every 2,000 cubic yards of soil or soil-rock fill placed and — compacted. - 7.2 The Consultant should perform a sufficient distribution of field density tests of the compacted soil or soil-rock fill to provide a basis for expressing an opinion whether the fill material is compacted as specified. Density tests shall be performed in the compacted materials below any disturbed surface. When these tests indicate that the density of any layer of fill or portion thereof is below that specified, the particular layer or areas represented by the test shall be reworked until the specified density has been achieved. 7.3 During placement of rock fill, the Consultant should observe that the minimum number of passes have been obtained per the criteria discussed in Section 6.3.3. The Consultant should request the excavation of observation pits and may perform plate bearing tests on the placed rock fills. The observation pits will be excavated to provide a basis for expressing an opinion as to whether the rock fill is properly seated and sufficient moisture has been applied to the material. When observations indicate that a layer of rock fill or any portion thereof is below that specified, the affected layer or area shall be reworked until the rock fill has been adequately seated and sufficient moisture applied. 7.4 A settlement monitoring program designed by the Consultant may be conducted in areas of rock fill placement. The specific design of the monitoring program shall be as recommended in the Conclusions and Recommendations section of the project Geotechnica] Report or in the final report of testing and observation services performed during grading. 7.5 The Consultant should observe the placement of subdrains, to verify that the drainage devices have been placed and constructed in substantial conformance with project specifications. 7.6 Testing procedures shall conform to the following Standards as appropriate: I I GI rev. 07/2013 7.6.1 Soil and Soil-Rock Fills: I 7.6.1.1 Field Density Test, ASTM D 1556-07, Density of Soil In-Place By the Sand-Cone Method. I 7.6.1.2 Field Density Test, Nuclear Method, ASTM D 6938-08A, Density of Soil and Soil-Aggregate In-Place by Nuclear Methods (Shallow Depth). I 7.6.1.3 Laboratory Compaction Test, ASTM D 1557-09, Moisture-Density Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound Hammer and 18-Inch Drop. I 7.6.1.4. Expansion Index Test, ASTM D 4829-08A, Expansion Index Test. 7.6.2 Rock Fills 7.6.2.1 Field Plate Bearing Test, ASTM D 1196-09 (Reapproved 1997) Standard Method for Nonreparative Static Plate Load Tests of Soils and Flexible Pavement Components, For Use in Evaluation and Design of Airport and Highway Pavements. 8. PROTECTION OF WORK 8.1 During construction, the Contractor shall properly grade all excavated surfaces to provide positive drainage and prevent ponding of water. Drainage of surface water shall be controlled to avoid damage to adjoining properties or to finished work on the site. The Contractor shall take remedial measures-to prevent erosion of freshly graded areas until such time as permanent drainage and erosion control features have been installed. Areas subjected to erosion or sedimentation shall be properly prepared in accordance with the Specifications prior-to placing additional fill or structures. 8.2 After completion of grading as observed and tested by the Consultant, no further I - excavation or filling shall be conducted except in conjunction with the services of the Consultant. I I - G1 rev. 07/2013 I 9. CERTIFICATIONS AND FINAL REPORTS Upon completion of the work, Contractor shall furnish Owner a certification by the Civil Engineer stating that the lots and/or building pads are graded to within 0.1 foot vertically of• elevations shown on the grading plan and that all tops and toes of slopes are within 0.5 foot horizontally of the positions shown on the grading plans. After installation of a section of subdrain, the project Civil Engineer should survey its location and prepare an as-built plan of the subdrain location. The project Civil Engineer should verify the proper outlet for the subdrains and the Contractor should ensure that the drain system is free of obstructions. 9.2 The Owner is responsible for furnishing a final as-graded soil and geologic report satisfactory to the appropriate governing or accepting agencies. The as-graded report should be prepared and signed by a California licensed Civil Engineer experienced in geotechnical engineering and by a California Certified Engineering Geologist, indicating that the geotechnical aspects of the grading were performed in substantial conformance with the Specifications or approved changes to the Specifications. Gi rev. 07/2013 RECORD COPY - 4L - ftiithl Date C) GEOTECHNICAL INVESTIGATION CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PREPARED FOR NEXUS PROPERTIESIWINDSTAR CARLSBAD OFFICE, LLC LA JOLLA, CALIFORNIA FEBRUARY 24, 2009 PROJECT NO. G1076-42-01 GEOCON INCORPORATED 1 GEOTECHNICAL CONSULTANTS Project No. G1076-42-01 February 24, 2009 Nexus Properties/Windstar Carlsbad Office, LLC 1149 North Torrey Pines Road, Suite 200 La Jolla, California 92037 Attention: Mr. Jeff Diltz Subject: CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA GEOTECI-INTCAL INVESTIGATION Dear Mr. Diltz In accordance with your authorization of our proposal (LG-08287, dated September 26, 2008) we herein submit the results of our geotechnical investigation for the subject site. We performed our investigation to assess the geologic conditions, potential geologic hazards, and to provide geotechnical engineering parameters for the design and construction of the proposed buildings and parking structure. The accompanying report presents the results of our study and conclusions and recommendations pertaining to geotechnical aspects of proposed development. The site is suitable for development provided the recommendations of this report are followed. If you have questions regarding this report, or if we may be of further service, please contact the undersigned at your convenience. Very truly yours, GEOCON INCORPORATED o ul (6/del) (2) CE 56468 CEO 2201 OfGARRY WELLS CANNON \i I No. 2201 l O.( cEmWIEO 1* W ENG1KERING GEOLOGIST ••) OFCA.\V Addressee Smith Consulting Architects Attention: Mr. Carl King 6960 Flanders .Drive 0 San Diego, California 92121-2974 • Telephone 1658) 558-6900 U Fax (858)558-6159 TABLE OF CONTENTS PURPOSE AND SCOPE . 1 SITE AND PROJECT DESCRIPTION ...................................... .................................................... I SOIL AND GEOLOGIC CONDITIONS........................................................................................2 3.1 Undocumented Fill (Qudf) .................................................................................................... 2 3.2 Terrace Deposits (Qt)............................................................................................................2 GROUNDWATER .......................................................................................................................... 3 GEOLOGIC HAZARDS.................................................................................................................3 5.1 Faulting and Seismicity.........................................................................................................3 5.2 Liquefaction Potential ................................................................ ............................................ 5 5.3 Ground Rupture ............................................................................................................. . ........ 5 5.4 Seiches and Tsunamis ......................................... .................................................................. s CONCLUSIONS AND RECOMMENDATIONS ..........................................................................6 6.1 General..................................................................................................................................6 6.2 Excavation and Soil Characteristics......................................................................................6 6.3 Seismic Design Criteria.........................................................................................................8 6.4 Grading..................................................................................................................................8 6.5 Temporary Excavation and Shoring Recommendations.....................................................10 FOUNDATION RECOMMENDATIONS ...................................................................................10 7.1 Retaining Walls ................................................................................................................... 11 7.2 Preliminary Pavement Recommendations ..........................................................................13 7.3 Site Drainage and Moisture Protection ...............................................................................16 7.4 Grading and Foundation Plan Review ................................................................................17 LIMITATIONS AND UNIFORMITY OF CONDITIONS MAPS AND ILLUSTRATIONS Figure 1, Vicinity Map Figure 2, Geologic Map Figure 3, Wall/Column Footing Dimension Detail Figure 4, Retaining Wall Drainage Detail APPENDIX A FIELD INVESTIGATION Figures A-I - A-6, Logs of Borings ( TABLE OF CONTENTS (Continued) APPENDIX B LABORATORY TESTING Table B-I, Summary of Laboratory Maximum Dry Density and Optimum Moisture Content Test Results Table B-Il, Summary of Laboratory Direct Shear Test Results Table B-Ill, Summary of Laboratory Expansion Index Test Results Table B-IV. Summary of Laboratory Water-Soluble Sulfate Test Results APPENDIX C EXPLORATORY BORING LOGS AND LABORATORY TEST DATA PERFORMED BY LEIGHTON AND ASSOCIATES APPENDIX D RECOMMENDED GRADING SPECIFICATIONS LIST OF REFERENCES GEOTECHNICAL INVESTIGATION 1. PURPOSE AND SCOPE- This report presents the results Of our geotechnical investigation for a proposed office campus located at 5600 Avenida Encinas, Carlsbad, California (see Vicinity Map, Figure 1). The purposes of our investigation was to evaluate subsurface soil and geologic conditions and, based on conditions encountered, provide conclusions and recommendations pertaining to geotechnical aspects of constructing the office campus and associated site improvements. To aid in preparing this report we have reviewed the following documents: Tentative Map for Carlsbad Of Campus, Sheet TM-I, Carlsbad, California, prepared by K&S Engineering, revision date March 26, 2004 (Job No. 0 1-048). 2. Geolechnical Investigation jbr Proposed Carlsbad Office Campus, 5600 Avenida Encinas, Carlsbad, California, prepared by Leighton & Associates, dated April 2, 2001 (Project No. 040382-001). We performed a field investigation on February 3, 2009, which consisted of a site reconnaissance and drilling 6, small-diameter borings to a maximum depth of approximately 15 feet. Exploratory boring logs and other details of the field investigation are presented in Appendix A. We performed laboratory tests on selected soil samples obtained during the field investigation to evaluate physical properties for engineering analyses and to assist in providing recommendations for site grading and foundation design criteria. Details of the laboratory tests and a summary of test results are presented in Appendix B. Boring logs and laboratory test data from previously submitted geotechnical report by Leighton & Associates are included in Appendix C. 2. SITE AND PROJECT DESCRIPTION The property is located along the west of Avenida Encinas north of Palomar Airport Road. The site is bound on the east side by Avenida Encinas, the North County Transit District railroad on the west, and office buildings on the north and south. A single story office building/floral-distribution warehouse with paved parking lots and access driveways currently occupies the site. Landscaping exists on the east side of the building. The property is at an elevation of approximately 55 feet above mean sea level (MSL) along the north side of the site to near 45 feet MSL at the west end. Based on a tentative map provided by K&S Engineering, 4, three-story, office buildings, and a two- level parking structure with associated utilities, pavement areas, a fountain and pond, and landscaping are planned for the site. Grading plans were not available for our review; however, proposed development is expected to consist of minor cuts and fills of approximately 3 feet or less to create level building pads. Based on information provided by the project architect, the eastern portion of the Project No. G 1076-42-01 - I - - February 24, 2009 parking structure will be situated approximately 5 feet below existing grade. The western portion of the structure will be constructed at grade. The locations and descriptions of the site and proposed development are based on a site reconnaissance, a review of the referenced plans and our understanding of project development. If project details vary significantly from those described above, Geocon incorporated should be contacted to determine the necessity for review and possible revision of this report. 3. SOIL AND GEOLOGIC CONDITIONS We encountered one soil type and one geologic formation during our field investigation. The soil unit consists of undocumented fill overlying Quaternary Terrace Deposits. The occurrence and distribution of the units are presented on the boring logs in Appendix A, and on the Geologic Map, Figure 2. The soil and geologic units are described below. 3.1 Undocumented Fill (Qudf) We encountered undocumented fill in each boring drilled during our field investigation. The undocumented fill was likely placed during construction of the existing building and parking lot. Documentation of the fill was not available. The undocumented fill consisted of loose to dense, moist, silty sand with trace gravel. The undocumented fill extended to depths of approximately 2 to 31/2 feet below existing grade. One boring drilled by Leighton & Associates during their investigation encountered undocumented fill to a depth of approximately 5 feet. The undocumented fill is unsuitable for the support of settlement-sensitive structures and improvements and will require removal and recompaction. 3.2 Terrace Deposits (Qt) Quaternary-age Terrace Deposits underlie the undocumented till to depths in excess of 15 feet throughout the site. The Terrace Deposits are mapped by Kennedy and Tan (2005) as undivided Old Paralic deposits of middle to late Pleistocene age ('Qop67,). The Terrace Deposits consist of dense to very dense,, silty, fine to medium sand and firm to stiff, sandy clay. We encountered the clay portion of the Terrace Deposits at the southwest corner of the site in borings B-4 and B-5. The clay layer had a thickness of approximately 2 to 8 feet. The clayey portions of the Terrace Deposits may have a high- expansion potential. Where the clayey layers of the Terrace Deposits are within 3 feet of finish pad grade, they should he removed and replaced with low expansive soil. The sandy portion of the Terrace Deposit is suitable for support of structural fill and settlement-sensitive structures. Project No. G1076-42-OI -2- February 24, 2009 4. GROUNDWATER We did not observe groundwater during our field investigation; however, we encountered seepage at depths ranging from approximately 11 to 13 feet below existing grade in borings B-I through B-3. Review of Leighton & Associates' referenced geotechnical investigation indicated that they encountered groundwater between depths of 13 and 17 feet. Utilities deeper than 10 feet may encounter seepage and/or groundwater. It is not uncommon for groundwater or seepage conditions to develop where none previously existed. Groundwater elevations are dependent on seasonal precipitation, irrigation, land use, among other factors, and vary as a result. Proper surface drainage will be important to future performance of the project. 5. GEOLOGIC HAZARDS 5.1 Faulting and Seismicity Based on our review of published geologic maps and previous geotechnical reports, the site is not located on any known active or potentially active fault trace as defined by the California Geological Survey (CGS). The California Geological Survey (CGS) defines an active fault as a fault showing evidence for activity within the last 11,000 years. The site is not located within State of California Earthquake Fault Zone. According to data generated using the computer program EZ-FRISK (Version 7.30), 13 known active faults are located within a search radius of 50 miles from the property. The nearest known active fault is the Rose Canyon Fault, located approximately 4 mile east of the site and is the dominant source of potential ground motion. Earthquakes that might occur on the Rose Canyon Fault Zone or other faults within the southern California and northern Baja California area are potential generators of significant ground motion at the site. The estimated deterministic maximum earthquake magnitude and peak ground acceleration for the Rose Canyon Fault are 7.2 and 0.43 g, respectively. Table 5.1.1 lists the estimated maximum earthquake magnitude and peak ground acceleration for the most dominant faults in relationship to the site location. We calculated peak ground acceleration (PGA) using Boore- Atkinson (2008) NGA USGS2008, Campbell-Bozorgnia (2008) NGA USGS 2008, and Chiou-Youngs (2008) NGA acceleration-attenuation relationships. Project No. G 1076-42-01 - 3 - February 24, 2009 TABLE 5.1.1 DETERMINISTIC SPECTRA SITE PARAMETERS Maximum Peak Ground Acceleration • Distance Earthquake Fault Name from Site Magnitude Boore- Campbell- Chiou- (miles) (Mw) Atkinson Bozorgnia Youngs 2008 (g) 2008 (g) 2008 (g) Rose Canyon 4 7.2 0.32 0.34 0.43 Newport-Inglewood (offshore) 6 7.2 0.27 0.27 0.33 Coronado Bank 20 7.7 0.18 0.13 0.18 Elsinore (Temecula) 25 7.2 0.12 0.09 0.10 Elsinore (Julian) 25 7.5 0.14 0.10 0.13 Elsinore (Glen-Ivy) 35 7.2 0.09 0.07 0.07 We used the computer program EZ-FRISK to perform a probabilistic seismic hazard analysis. The computer program EZ-FRISK operates under the assumption that the occurrence rate of earthquakes on each mapped Quaternary fault is proportional to the faults' slip rate. The program accounts for fault rupture length as a function of earthquake magnitude. Site acceleration estimates are made using the earthquake magnitude and distance from the site to the rupture zone. The program also accounts for uncertainty in each of following: (I) earthquake magnitude, (2) rupture length for a given magnitude, (3) location of the rupture zone, (4) maximum possible magnitude of ,a given earthquake, and (5) acceleration at the site from a given earthquake along each fault. By calculating the expected accelerations from considered earthquake sources, the program calculates the total average annual expected number of occurrences of site acceleration greater than a specified value. We utilized acceleration-attenuation relationships, suggested by Boore-Atkinson (2008) NGA USGS2008, Campbell-Bozorgnia (2008) NGA USGS 2008, and Chiou-Youngs (2008) in the analysis. Table 5.1.2 presents the site-specific probabilistic seismic hazard parameters including acceleration-attenuation relationships and the probability of exceedence. TABLE 5.1.2 PROBABILISTIC SEISMIC HAZARD PARAMETERS Probability of Exceedence Peak Ground Acceleration Boore-Atkinson, 2008 (g) Campbell-Bozorgnia, 2008 (g) Chiou-Youngs, 2008 (g) 2% in a 50 Year Period 0.52 0.53 0.66 in a 50 Year Period 0.38 1 0.39 1 0.48 10% in a 50 Year Period 0.29 10.29 1 0.34 Project No. G1076-42-ol -4- February 24, 2009 The CGS provides a computer program for the calculation of ground acceleration having a 10 percent of probability of exceedence in 50 years based on an average of several attenuation relationships. Table 5.1.3 presents the results from the Probabilistic Seismic Hazards Mapping Ground Motion Page from the CGS website. TABLE 5.1.3 PROBABILISTIC SITE PARAMETERS FOR SELECTED FAULTS CALIFORNIA GEOLOGIC SURVEY Calculated Acceleration (g) Firm Rock Calculated Acceleration (g) Soft Rock Calculated Acceleration (g) Alluvium 0.28 0.30 0.33 While listing peak accelerations is useful for comparison of potential effects of fault activity in a region, other considerations are important in seismic design, including the frequency and duration of the ground motion and the soil conditions underlying the site. Seismic design of the structures should be performed in accordance with the current California Building Code (CBC) guidelines. 5.2 Liquefaction Potential The potential for liquefaction at the site is very low due to the density of the Terrace Deposits and the lack of pernianent, near-surface groundwater. It is our opinion that the potential for seismically induced settlement is very low. 5.3 Ground Rupture No active or potentially active faults cross the site. The potential for ground rupture is very low. 5.4 Seiches and Tsunamis The potential of seiches to occur is considered to be very low due to the absence of a nearby body of water. The potential of tsunamis impacting the site is low as the site is located approximately 0.25 miles from the shore at an elevation of approximately 45 to 50 feet above MSL. Project No. G1076-42-01 - 5 - February 24, 2009 6. CONCLUSIONS AND RECOMMENDATIONS 6.1 General 6.1 .1 From a geotechnical standpoint, it is our opinion that the site is suitable for the proposed buildings and parking structure, provided the recommendations presented herein are implemented in design and construction of the project. 6.1.2 Undocumented fill and Quaternary Terrace Deposits underlie the site. The undocumented fill is unsuitable for support of proposed improvements and will require remedial grading. With the exception of the potentially expansive clay layer, the Terrace Deposits are suitable for support of proposed buildings and improvements. Highly expansive soils should be removed and replaced with low expansive soils if encountered within 3 feet of pad grade. Based on our review of the boring logs, we expected that expansive clays will be encountered at the southwest corner of the site. 6.1.3 Seepage was encountered near depths of approximately 11 to 13 feet. Leighton & Associates documented groundwater at a depth of 13 to 17 feet in their geotechnical investigation. Groundwater and/or seepage-related problems are not expected adversely impact the proposed surface improvements. However, excavations for utilities deeper than 10 feet may encounter seepage. 6.1.4 With the exception of possible seismic shaking, no geologic hazards were observed nor are any known to exist on the site that would adversely affect the proposed project. Based on published literature and the findings of this investigation, it is our opinion that known active, potentially active, or inactive faults do not cross the site. The potential for geologic hazards due to ground rupture, liquefaction, and tsunamis or seiches is considered to be very low. 6.1.5 The proposed office buildings and parking structure can be supported on conventional shallow footings founded in properly compacted fill or Quaternary Terrace Deposits. 6.2 Excavation and Soil Characteristics 6.2.1 The soil encountered in the field investigation is considered to be "non-expansive" to "expansive" (expansion index [El] of greater less than 20 and greater than 20) as defined by 2007 California Building Code (CBC) Section 1802.3.2. Expansion index tests performed on samples from our field investigation indicated an El ranging from 2 to 88. Table 6.2.1 presents soil classifications based on expansion index. Project No. G 1076-42-01 - 6 - February 24, 2009 TABLE 6.2.1 SOIL CLASSIFICATION BASED ON EXPANSION INDEX Expansion Index (El) Soil Classification 0-20 Very Low 21-50 Low 51-90 Medium 91-130 High Greater Than 130, Very High 6.2.2 Grading can be accomplished with moderate to heavy effort using conventional heavy-duty equipment. Concretions are not uncommon within the formational materials and may require special excavation equipment if encountered. 6.2.3 It is the contractors' responsibility to provide a safe working environment and to maintain the stability of adjacent existing improvements. The excavations and trenches should be properly shored and maintained in accordance with the applicable OSHA rules and regulations.. 6.2.4 We performed laboratory tests on samples of the site soils to evaluate the percentage of water-soluble sulfate. The results of the tests are presented in Appendix B and indicate that the on-site soil samples possess a "negligible" sulfate exposure to concrete structures as defined by 2007 CBC Section 1904.3 and ACI 318. The presence of water-soluble sulfates is not a visually discernible characteristic; therefore, other soil samples from the site could yield different concentrations. Additionally, over time landscaping activities (i.e., addition of fertilizers and other soil nutrients) may affect the. concentration. 6.2.5 Laboratory pH and resistivity tests performed by Leighton & Associates during their previous geotechnical investigation indicate some of the site soils have a "moderately corrosive" to "severely corrosive" corrosion potential rating with respect to buried metal. The corrosive nature of the soils should be considered in the design of buried metal pipes and underground structures. 6.2.6 Geocon incorporated does not practice in the field of corrosion engineering. Therefore, if improvements are planned that could be susceptible to corrosion, it is recommended that further evaluation by a corrosion engineer be performed. Project No. G 1076-42-01 - 7 - February 24, 2009 6.3 Seismic Design Criteria 6.3.1 We used the computer program Seismic Hazard Curves and Unifbrin Hazard Response Spectra, provided by the USGS. Table 6.3.1 summarizes site-specific design criteria obtained from the 2007 California Building Code (CBC). The short spectral response uses a period of 0.2 second. TABLE 6.3.1 2007 CBC SEISMIC DESIGN PARAMETERS Parameter Value CBC 2007 Reference Site Class C Table 1613.5.2 Spectral Response - Class B (short), Ss 1.321 g Figure 1613.5(3) Spectral Response Class B (1 sec), S1 0.499 g Figure 16 13.5(4) Site Coefficient, FA 1.000 Table 1613.5.3(1) Site Coefficient, F, 1.301 Table 1613.5.3(2) Maximum Considered Earthquake Spectral Response Acceleration (short), SMS 1.32 1 g Section 1613.5.3 (Eqn 16-37) Maximum Considered Earthquake Spectral Response Acceleration —(1 sec), , 0.649 g Section 1613.5.3 (Eqn 16-38) 5°4 Damped Design Spectral Response Acceleration (short), 5D5 0.881 g Section 1613.5 .4 (Eqn 16-39) 5% Damped Design Spectral Response Acceleration (1 see), SD, 0.433 g Section 1613.5.4 (Eqn 1640) 6.3.2 Conformance to the criteria in Table 6.3.1 for seismic design does not constitute any kind of guarantee or assurance that significant structural damage or ground failure will not occur if a large earthquake occurs. The primary goal of seismic design is to protect life, not to avoid all damage, since such design could be economically prohibitive. 6.4 Grading 6.4.1 Grading should be performed in accordance with the Recommended Grading Specifications contained in Appendix D. Where the recommendations of Appendix D conflict with this section of the report, the recommendations of this section take precedence. 6.4.2 A pre-construction conference should be held at the site with the owner or developer, grading contractor, civil engineer, geotechnical engineer, and City officials in attendance. Special soil handling requirements can be discussed at that time. Project No. G1076-42-01 - 8 - February 24, 2009 64.3 Grading of the site should begin with the removal of existing improvements and deleterious material from the areas to be graded. The foundations of the existing structure should be completely removed. Deleterious materials should be exported from the site and should not be mixed with the fill soil. Existing underground improvements within proposed new building areas should be removed and the resulting excavations properly backfilled in accordance with the procedures described herein. 6.4.4 Undocumented fill within structural improvement areas should be completely removed to expose the dense, underlying, Quaternary Terrace Deposits. We expect removal depths of 2 to 5 feet across the property. The estimated depths to formational soils are shown on the Geologic Map, Figure 2. 6.4.5 Where the expansive clay portion of the Terrace Deposits exists within 3 feet of pad grade, the clay layer should be removed and replaced with low expansive soils. Clay soils should not be reused within building and structural improvement areas. The clay soils are suitable for placement as non-structural fill. 6.4.6 To reduce the potential for differential settlement the building pads should be graded to provide at least 1-foot of compacted fill beneath the lowest foundation element. This may require undercutting portions of the building pads The undercut should extend at least 5 feet beyond the building footprint. Foundation plans should be reviewed prior to grading to establish the minimum depth of the undercut necessary to achieve minimum 1-foot of fill beneath the footings. 6.4.7 Excavated soil, which is generally free of deleterious debris, may be used as fill. Prior to placing fill, the base of overexcavations and areas to receive fill, should be scarified to a depth of at least 12 inches, moisture conditioned, and compacted. Fill soil may then be placed and compacted in layers to finish grade elevations. The fill layers should be no thicker than will allow for adequate bonding and compaction. Fill soil (including scarified ground surfaces and backfill) should be compacted to at least 90 percent of maximum dry density near to or slightly above optimum moisture content, as determined by ASTM Test Procedure D 1557-02. 6.4.8 Imported fill should consist of granular soils with having a 'very low" to "low" expansion potential (El of 50 or less) and be free of deleterious material and stones larger than 3 inches. Geocon Incorporated should be notified of the source of the imported soil and should be authorized to perform laboratory testing of soil prior to its arrival at the site to evaluate its suitability as fill material. Project No. G 1076-42-01 - 9 - February 24, 2009 6.4.9 Earthwork should be observed and compacted fill tested by representatives of Geocon Incorporated. 6.5 Temporary Excavation and Shoring Recommendations 6.5.1 Temporary slopes should be constructed in conformance with OSHA requirements. Compacted fill and Terrace Deposits can be considered a Type B soil (Type C soil if seepage is encountered) in accordance with OSHA requirements. In general, special shoring requirements will not be necessary if temporary vertical excavations will be less than 4 feet high. Temporary excavation depths greater than 4 feet should be sloped back at an appropriate inclination in accordance with OSHA requirements. Surcharge loads should not be placed near the excavation within a distance equal to the depth of the excavation. The excavation should be a minimum of 15 feet from the edge of existing improvements. Excavations steeper than those recommended or closer than 15 feet from an existing surface improvement should be shored in accordance with applicable OSHA codes and regulations. 7.0 Foundation Recommendations 7.1 Conventional, continuous footings should be at least 18 inches wide and founded at least 24 inches below lowest adjacent pad grade. Continuous footings should be reinforced with four, No. 5 steel, reinforcing bars, two placed near the top of the footing and two near the bottom. Isolated spread. footings should be a minimum of 2.5 feet square and founded at least 24 inches below lowest adjacent pad grade. The project structural engineer should design reinforcement for spread footings. A typical wall/column footing dimension detail depicting the depth to lowest adjacent grade is presented on Figure 3. 7.2 The recommended allowable bearing capacity for isolated spread footings and continuous footings with minimum dimensions described above is 3,000 pounds per square foot (psf). The soil bearing pressure may be increased by 300 psf for each additional foot of foundation with and 500 psf for each additional foot of foundation depth, up to a maximum allowable soil bearing pressure of 4,000 psf. The allowable bearing pressure may be increased by up to one-third for transient loads due to wind or seismic forces. 7.3 Concrete slabs-on-grade should he at least 5 inches thick and reinforced with No. 4 bars spaced 18 inches on center in both directions and placed at the slab midpoint. Concrete slabs on grade should be underlain by 3 inches of clean sand to reduce the potential for differential curing, slab curl, and cracking. A vapor retarder placed near the middle of the sand bedding beneath slabs that could receive moisture-sensitive floor coverings or may be used to store moisture-sensitive materials. The project architect or developer should specify the vapor retarder. The vapor retarder design should be consistent with the guidelines presented in Project No. G 1076-42-01 - 10 - February 24, 2009 Section 9.3 of the American Concrete Institute's (AC!) Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials (ACT 302.2R-06). 7.4 No special subgrade presaturation (i.e., flooding to saturate soils to foundation depths to mitigate highly expansive soils) is deemed necessary prior to placement of concrete. However, the slab and foundation subgrade should be sprinkled as necessary to maintain a moist condition as would be expected in any concrete placement. 7.5 Exterior slabs or concrete flatwork not subject to vehicular traffic should be a minimum of 4 inches thick. Slab panels should be reinforced with 6X6-W2.9/W2.9 (6x6-6/6) welded wire mesh. The mesh should be placed within the upper one-third of the slab. Proper mesh positioning is critical to future performance of the slabs. It has been our experience that the mesh must be physically pulled up into the slab after concrete placement. The contractor should take extra care to provide proper mesh placement. 7.6 Concrete slabs should be provided with adequate construction joints and/or expansion joints to control unsightly shrinkage cracking. The project structural engineer should provide crack-control spacing based on the intended slab usage, type and extent of floor covering materials, slab thickness, and reinforcement. The structural engineer should take into consideration criteria of the American Concrete Institute when establishing crack-control spacing patterns. 7.7 The recommendations of this report are intended to reduce the potential for cracking of slabs due to differential movement due to fills of varying thickness or expansive soils, if present. However, even, with the incorporation of the recommendations presented herein, foundations, stucco walls, and slabs-on-grade placed on such soil conditions may exhibit some cracking due to soil movement and/or shrinkage. The occurrence of concrete shrinkage cracks is independent of the supporting soil characteristics. Their occurrence may be reduced and/or controlled by limiting the slump of the concrete, proper concrete placement and curing, and by the placement of crack control joints at periodic intervals, in particular, where re-entrant slab corners occur. 7.1 Retaining Walls 7.1.1 Retaining walls that are allowed to rotate more than 0.001H at the top of the wall and having a level backfill surface should be designed for an active soil pressure equivalent to the pressure exerted by a fluid density of 40 pounds per cubic foot (pcf). Where the backfill will be inclined at no steeper than 2:1 (horizontal: vertical), an active soil pressure of 55 pcf is recommended. These soil pressures assume that the backfill materials within an area Project No. 01076-42-01 - I I - February 24, 2009 bounded by the wall and a I :1 plane extending upward from the base of the wall possess an Expansion Index of less than 50. For those lots with finish grade soils having an Expansion Index greater than 50 and/or where backfill materials do not conform to the above criteria, Geocon Incorporated should be consulted for additional recommendations. 7.1.2 For rigid, restrained walls, an additional uniform pressure of 811 psf (where H equals the wall height in feet) should be added to the above active soil pressure. 7.1.3 The structural engineer should determine the seismic design category for the project. If the project possesses a seismic design category of D, E, or F, retaining walls should be designed with seismic lateral pressure. The seismic load exerted on the wall should be a triangular distribution with a pressure of 20H (where H is the height of the wall, in feet, resulting in pounds per square foot [psf]) exerted at the top of the wall and zero at the base of the wall. We used a peak site acceleration of 0.35g calculated from the 2007 California Building Code (S s/2.5) and applying a pseudo-static coefficient of 0.5. 7.1.4 Although this seismic loading on the wall was evaluated for an active pressure case and the walls will be in an at-rest condition, some researchers have reported that this analysis produces reasonable design earth pressures. Because seismic loads will be analyzed using lower factors of safety than static earth pressures, we expect the design can be controlled by static loads. 7.1.5 Retaining walls should be provided with a drainage system adequate to prevent the buildup of hydrostatic forces and should be waterproofed as required by the project architect. The use of drainage openings through the base of the wall (weep holes) is not recommended where the seepage could be a nuisance or otherwise adversely impact the property adjacent to the base of the wall. Figure 4 presents a typical retaining wall drainage detail. The above recom- mendations assume a properly compacted granular (El less than 50) backfill material with no hydrostatic forces or imposed surcharge load. If conditions different than those described are anticipated, or if specific drainage details are desired, Geocon Incorporated should be contacted for additional recommendations. 7.1.6 In general, wall foundations having a minimum depth and width of one foot may be designed for an allowable soil bearing pressure of 2,000 psf, provided the soil within 3 feet below the base of the wall has an Expansion Index of 50 or less. The proximity of the foundation to the top of a slope steeper than 3:1 could impact the allowable soil bearing pressure. Therefore, Geocon Incorporated should be consulted where such a condition is expected. Project No. G 1076-42-() I - I 2 - - February 24, 2009 In 7.1.7 Footings for retaining walls that act as building walls should be designed in accordance with the foundation recommendations of Section 7.0 of this report. 7.1 .8 For resistance to lateral loads, an allowable passive earth pressure equivalent to that exerted by a fluid having a density of 350 pcf is recommended for footings or shear keys poured neat against properly compacted granular fill soils or undisturbed natural soils. The allowable passive pressure estimate assumes there is a horizontal surface extending away from the base of the wall at least 5 feet or three times the height of the surface generating the passive pressure, whichever is greater. The upper 12 inches of soil not protected by floor slabs or pavement should not be included in the calculation of the lateral resistance. An allowable friction coefficient of 0.4 may be used for resistance to sliding between soil and concrete. The friction coefficient may be combined with the allowable passive earth pressure when determining resistance to lateral loads. 7.2 Preliminary Pavement Recommendations 7.2.1 The following preliminary pavement sections are based on an R-Value of 21 (value determined from laboratory testing). Final pavement sections should be calculated once subgrade elevations have been attained and R-Value testing on subgrade samples is performed. 7.2.2 Flexible pavement sections were calculated following procedures outlined in the California Highway Design Manual (Caltrans) and information provided on City of Carlsbad's Structural Section of Streets and Alleys (GS-17). Rigid pavement sections are based on methods suggested by the American Concrete Institute Guide for Design and Construction of Concrete Parking Lots (ACI 330R-01). Interlocking concrete paver base sections were calculated in general conformance with the Interlocking Concrete Pavement Institute Technical guidelines (ICP1 Tech Spec Number 4, Structural Design of Interlocking Concrete Pavement jbr Roads and Parking Lots. Paver installation should be performed in accordance with ICPI Tech Spec 2, Construction of Interlocking Concrete Pavement. With respect to interlocking concrete payers, we recommend the payers be underlain by the same base section required for a flexible pavement system using an equivalent concrete paver thickness (i.e., 3 inches of asphalt concrete equivalent to a 3-inch-thick concrete paver). 7.2.3 It is anticipated that the majority of traffic will consist of automobile traffic with minor heavy truck traffic. We have assumed Traffic Indicies (TI) of 4.5 for automobile parking areas, 5.0 for automobile driveways, and 7.0 for heavy truck/fire access areas. The developer or project architect should determine the appropriate locations for the different traffic loads. Table 7.2.1 summarizes preliminary pavement sections. General recommendations for Project No. G 1076-42-01 - 13 - - February 24, 2009 asphalt concrete, rigid concrete, and interlocking concrete paver sections are included hereinafter. TABLE 7.2.1 PRELIMINARY ASPHALT CONCRETE AND PORTLAND CEMENT CONCRETE PAVEMENT DESIGN SECTIONS Asphalt Concrete Estimated Section Portland Cement Asphalt Class 2 Location Traffic Index Concrete Section (TI) Concrete Base (inches) (inches) (inches) Automobile Parking 4.5 4 4 5 Automobile Driveways 5 4 5 6 Heavy Truck/Fire Lanes 6 4 10 7 - . TABLE 7.2.2 PRELIMINARY PAVEMENT SECTIONS FOR - INTERLOCKING CONCRETE PAVERS Design Traffic Concrete Paver Class 2 Base Location Index Thickness (inches) (TI) (inches) Automobile Parking 4.5 3 6 Automobile Driveways 5 3 7 Heavy Truck/Fire Areas 6 3 12 7.2.4 Asphalt concrete should conform to Section 203-6 of the Standard SpecUications for Public Works Construction (Green Book). Class 2 aggregate base materials should conform to Section 26-1.02A of the Standard Specifications of the State of California, Department of Transportation (Caltrans). 7.2.5 Prior to placing base material, the subgrade soil should be scarified, moisture conditioned to near optimum moisture content, and compacted to a minimum of 95 percent of the maximum dry density. The depth of compaction should be at least 12 inches. Base material should be compacted to at least 95 percent of the laboratory maximum dry density at/or near optimum moisture content. Asphalt concrete should be compacted to at least 95 percent maximum Hveern density. Project No. G1076-42-Ol - 14- February 24, 2009 7.2.6 Interlocking payers should be placed directly adjacent to one another to minimize areas where water can percolate down into the base and subgrade. In addition, a sealant to bind the sand between the payers should be used. 7.2.7 Concrete edge bands or curbs should be incorporated into the pavement section to maintain horizontal interlock while the interlocking payers and turf block are subjected to vehicular loads. 7.2.8 A maintenance schedule consisting of inspecting the pavement sections should be established and periodic, removal and replacement of individual payers may be required. 7.2.9. Loading aprons such as trash bin enclosures should be use a rigid pavement section as recommended for truck traffic areas. The pavement should be reinforced with No. 3 steel, reinforcing bars spaced 24 inches on center in both directions placed at the slab midpoint. The concrete apron should large enough for both the front and rear wheels of the trash truck to be located on reinforced concrete pavement when loading. 7.2.10 Where landscape or landscape planters are planned adjacent to pavement surfaces, the perimeter curb should extend at least 6 inches below the level of the Class 2 aggregate base. 7.2.11 The performance of pavements is highly dependent upon providing positive surface drainage away from the edge of pavements. Ponding of water on or adjacent to the pavement will likely result in saturation of the subgrade materials and subsequent pavement distress. 7.2.12. The following recommendations are being provided for Portland cement concrete pavement areas. The project structural engineer should provide specification for the reinforcement of the concrete slabs. The rigid pavement recommendations outlined on Table 7.2.1 are based on a minimum concrete flexural strength (modulus of rupture, MR) of 500 pounds per square inch (psi) (compressive strength of 3,200 psi), a modulus of subgrade reaction, k, of 100 pounds per cubic inch (pci), with an assumed design period of 20 years. A thickened edge or integral curb should be constructed on the outside of concrete slabs subjected to wheel loads. The thickened edge should be 1.2 times the slab thickness at the slab edge and taper to the recommended slab thickness 3 feet behind the face of the slab (e.g., a 7-inch-thick slab would have an 8.4-inch-thick edge). To control the location and spread of concrete shrinkage cracks, it is recommended that crack control joints be included in the design of the concrete pavement slab. Crack Project No. G 076-42-01 - 1 5 - . February 24, 2009 control joint spacing should not exceed, in feet, twice the recommended slab thickness in inches (e.g., 14 by 14 feet for a 7-inch-thick slab). The crack control joints should be created while the concrete is still fresh using a grooving tool, or shortly thereafter using saw cuts. The joint should extend into the slab a minimum of one-fourth of the slab thickness. Expansion joints should be provided at the interface between areas of concrete placed at different times during construction. Doweling is recommended between the joints to transfer anticipated truck traffic loading. Dowels should be located at the midpoint of the slab and be spaced at 12 inches on center. As an alternative to doweling, a keyway may be used to transfer wheel loads. The keyway should have a width of 0.2 times the slab thickness and a depth equal to 0.1 times the slab thickness (e.g., for a 7-inch-thick slab the keyway would have a width of approximately 1.4 inches and a depth of 0.7 inches). The project structural engineer should provide specifications for load transfer details. Consideration should be given to the use of a crack control joint and expansion joint filler or sealer to mitigate infiltration of water into subgrade and base materials. Appropriate fillers or sealers are discussed in section 6.3 of the referenced ACT guide. 7.3 Site Drainage and Moisture Protection 7.3.1 Adequate site drainage is critical to reduce the potential for differential soil movement, erosion and subsurface seepage. Under no circumstances should water be allowed to pond adjacent to footings. The site should be graded and maintained such that surface drainage is directed away from structures in accordance with 2007 CBC 1803.3 or other applicable standards.. In addition, surface drainage should be directed away from the top of slopes into swales or other controlled drainage devices. Roof and pavement drainage should be directed into conduits that carry runoff away from the proposed structures. 7.3.2 Basement walls or building walls retaining landscaping areas, a water proofing system should be used on the wall and joints, and a Miradrain drainage panel, or similar, should be placed over the water proofing. A perforated, Schedule 40, PVC drainpipe should be installed at the base of the wall below the floor slab and drained to an appropriate discharge area. The project architect or civil engineer should provide detailed specifications on the plans for all waterproofing and drainage. 7.3.3 An impermeable liner should be placed beneath the proposed water features planned for the center of the site to prevent water seepage from the embankment sides and pond bottom. 7.3.4 Underground utilities should be leak free. Utility and irrigation lines should be checked periodically for leaks for early detection of water infiltration and detected leaks should be Project No. G 1076-42-01 - I 6 - February 24, 2009 repaired promptly. Detrimental soil movement could occur if water is allowed to infiltrate the soil for a prolonged period of time. 7.3.5 If detention basins, hioswales, retention basins, or water infiltration devices are being considered, Geocon Incorporated should be retained to provide recommendations pertaining to the geotechnical aspects of possible impacts and design. Distress may be caused to planned improvements and properties located hydrologically downstream. The distress depends on the amount of water to be detained, its residence time, soil permeability, and other factors. We have not performed a hydrogeology study at the site. Downstream properties may be subjected to seeps, springs, slope instability, raised groundwater, movement of foundations and slabs, or other impacts as a result of water infiltration. 7.3.6 Landscaping planters immediately adjacent to paved areas are not recommended due to the potential for surface or irrigation water to infiltrate the pavement's subgrade and base course. Either suhdrains, which collect excess irrigation water and transmit it to drainage structures, or impervious, above-grade planter boxes should be used. In addition, where landscaping is planned adjacent to the pavement, it is recommended that consideration be given to providing a cutoff wall along the edge of the pavement that extends at least 12 inches below the base material. 7.4 Grading and Foundation Plan Review 7.4.1 Grading and foundation plans should be reviewed by an engineer and/or engineering geologist prior to finalization to verify that the plans have been prepared in substantial conformance with the recommendations of this report and to provide additional analyses or recommendations. Project No. G 1076-42-01 - 17 - February 24, 2009 LIMITATIONS AND UNIFORMITY OF CONDITIONS The firm that performed the geotechnical investigation for the project should be retained to provide testing and observation services during construction to provide continuity of geotechnical interpretation and to check that the recommendations presented for geotechnical aspects of site development are incorporated during site grading, construction of improvements, and excavation of foundations. If another geotechnical firm is selected to perform the testing and observation services during construction operations, that firm should prepare a letter indicating their intent to assume the responsibilities of project geotechnical engineer of record. A copy of the letter should be provided to the regulatory agency for their. records. In addition, that firm should provide revised recommendations concerning the geotechnical aspects of the proposed development, or a written acknowledgement of their concurrence with the recommendations presented in our report. They should also perform additional analyses deemed necessary to assume the role of Geotechnical Engineer of Record. The recommendations of this report pertain only to the site investigated and are based upon the assumption that the soil conditions do not deviate from those disclosed in the investigation. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that expected herein, Geocon Incorporated should be notified so that supplemental recommendations can be given. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by Geocon Incorporated. This report is issued with the understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. The findings of this report are valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. Project No. GO76-42-01 - February 24, 2009 SOURCE: 2007 THOMAS BROTHERS MAP SAN DIEGO COUNTY, CALIFORNIA Map © Rand McNally, R.L.08-S-100, reproduced with permission. It is unlawful to copy NO SCALE or reproduce, whether for personal use or resale, without permission GE000N INCORPORATED (00) GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121- 2974 PHONE 858 558-6900 - FAX 858 558-6159 NBIAML DSK/GTYPD I VICINITY MAP I CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA DATE 02 - 24 - 2009 1 PROJECT NO. G1076 42Ol 1 FIG. 1 CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA L*DONO GE000N LEGEND Qudf UNDOCUMENTED FILL Qt ........TERRACE DEPOSITS APPROX. LOCATION OF EXPLORATORY BORING APPROX. LOCATION OF EXPLORATORY BORING (LeIghton & Annocotee, 2001) (3.51 ........APPROX. DEPTH TO FORMATIONAL MATERIALS (In Foot XI5TnC JtOING GEOCON INCORPORATED GEO15O1NCALO5NSUtTANTS 6960R.ANDPO DRIVE ' SAN DEGO, CAUFORMA921ST-2974 PHONE 858 558-6900-FAX &5B 558-6159 PROJECT NO. G1076 .42 -01 GEOLOGIC "G" è.. AD FIGURE 2 AJL\J I IVUF DATE 02-24-2009 WALL FOOTING CONCRETE SLAB I 4 44 SAND— _'••'\ PAD GRADE MOISTURE INHIBITOR\' : 00 LL .• FOOTING WIDTH COLUMN FOOTING SAND 4 SAND MOISTURE_VI 4 4 INHIBITOR .'• . . .4 .. :• . .•. :•. > •. : •• • ••-. > Lu On LL 4444 9 49 '/•• .- _ FOOTING WIDTH NO SCALE *SEE REPORT FOR FOUNDATION WITDH AND DEPTH RECOMMENDATION WALL [COLUMN FOOTING DIMENSION DETAIL GEO.CON INCORPORATED 91 GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE- SAN DIEGO, CALIFORNIA 92121- 2974 PHONE 858 558-6900 - FAX 858 558-6159 NB/AML I I DSK/E0000 0tJr2DwG/.,d CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA DATE 02-24-2009 I PROJECT NO. Gb0764201 FIG.3 CONCRETE GROUND SURFACE BROWDITCH PROPOSED - RETAINING WALL .. \'\\PRO \ \\\\LY COMPACTED " BACKFILL TEMPORARY BACKCUT s \\\\\\\ / PER OSHA - - 2 2/3H MIRAFI 140N FILTER FABRIC - -: (OR EQUIVALENT) -: OPEN GRADED - • ? MAX. AGGREGATE GROUND SURFACE "Mj (j I_• FOOliNG 4 DIA. PERFORATED SCHEDULE L-1 40 PVC PIPE EXTENDED TO APPROVED OUTLET 12 CONCRETE ,—GROUND SURFACE BROWDITCH RETAINING - WALL - WATER PROOFING - - PER ARCHITECT - DRAINAGE PANEL (MIRADRAIN 6000 - _- OR EQUIVALENT) 2/3H - 3/4 CRUSHED ROCK (11 CU.FT./FT.) - FILTER FABRIC ENVELOPE PROPOSED MIRAFI 140N OR EQUIVALENT GRADE - 4 DIA. SCHEDULE 40 PERFORATED PVC PIPE OR TOTAL DRAIN EXTENDED FOOTING TO APPROVED OUTLET NOTE: DRAIN SHOULD BE UNIFORMLY SLOPED TO GRAVITY OUTLET OR TO A SUMP WHERE WATER CAN BE REMOVED BY PUMPING NO SCALE TYPICAL RETAINING WALL DRAIN DETAIL GE000N Aft INCORPORATED CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA GEOTECHNICAL CONSULTANTS 6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121- 2974 PHONE 858 558-6900 - FAX 858 558-6159 NB/AML DSK/GTYPD I I DATE 02-24-2009 PROJECT NO. G1076 -42-01 FIG. 4 i APPENDIX APPENDIX A FIELD INVESTIGATION We performed the subsurface exploration on February 3, 2009. The subsurface exploration consisted of drilling 6, small-diameter borings to a maximum depth of approximately 15 feet using an ingersol Rand-300 drill rig equipped with 8-inch-diameter, hollow-stem augers. The approximate locations of the exploratory borings are shown on the Geologic Map, Figure 2. Boring logs and an explanation of the geologic units encountered are presented in this appendix. We obtained samples using a Modified California Sampler. The Modified California sampler has an inside diameter of 2.5 inches and an outside diameter of 3 inches. Up to 18 rings are placed inside the sampler that is 2.4 inches in diameter and 1-inch in height. We obtained ring samples at appropriate intervals, placed them in moisture-tight containers, and transported them to the laboratory for testing. The type of sample is noted on the exploratory boring logs. The sampler was driven 12 inches into the bottom of the boring excavation with the use of an cathead hammer and A-rods. The sampler was driven using a 140-pound hammer with a 30-inch drop. The penetration resistance values shown on the boring logs are shown in terms of blows per foot. These values are not to be taken as N-values as adjustments have not been applied. We estimated the ground elevations shown on the boring logs from the referenced tentative map. Each excavation was backfilled as noted on the boring logs. t Project No. G1076-42-01 February 24, 2008 PROJECT NO. G1076-42-01 Of BORING DEPTH >- ,- < SOIL Qo If) l)-_-Of Z IN SAMPLE 0 CLASS ELEV. (MLLW) 50' DATE COMPLETED 02-03-2009 0 FEET - ZwLOW cü IX 20 EQUIPMENT IR-300 BY: N.N. BORJA 0 0 MATERIAL DESCRIPTION ASPHALT CONCRETE 3 inches SM - - - \ BASE 4 inches UNDOCUMENTED FILL • Loose, moist, dark reddish brown, Silty, fine to medium SAND; trace gravel 2 - - - - BI-1 - -Becomes dense 43 SM TERRACE DEPOSITS I Dense, moist, mottled reddish brown and yellowish brown, Silty, fine to - 4 - medium SAND - - - Bl-2 38 - 6 - BI-3 H. - - 8 - - - - -Becomes mottled reddish brown and light gray; trace mica - -10- 81-4 :tH 94 - BI-5 -f - 12- - LLy : -Seepage at 13 feet - -Becomes wet, mottled yellowish brown and light gray 14 - BI-6 - 76 •-•_ ______________ __ BORING TERMINATED AT 15 FEET Seepage encountered at 13 feet Backfilled with cuttings Figure A-I, Log of Boring B I, Page lofl SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL I STANDARD PENETRATION TEST U DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE CHUNK SAMPLE •.. WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GE000N PROJECT NO. G1076-42-01 BORING z >- DEPTH o SOIL ' IN FEET SAMPLE NO. 0 CLASS ELEV.(MLLW.) 5V DATE COMPLETED 02-03-2009 0 :i 0 EQUIPMENT IR-300 BY: N.N. BORJA MATERIAL DESCRIPTION 0 - ASPHALT CONCRETE 2V2 inches SM \BASE 4inches UNDOCUMENTED FILL - - 132-I Loose to medium dense, moist, dark reddish brown to dark brown, Silty, fine - 2 - to medium SAND; trace gravel B2-2 .39 - SM TERRACE DEPOSITS - 4 - Dense, moist, mottled reddish brown and yellowish brown, Silty, fine to medium SAND; little mica flakes and manganese oxides; weathered - - 132-3 F. - 41 - 6 - 1324 -8 - - - . -Becomes mottled reddish brown and light gray - -10- 132-5 45 B2-6 H - 12- - -Seepage at 13 feet 14 1327 -No recovery 42 BORING TERMINATED AT 15 FEET Seepage encountered at 13 feet Backfilled with cuttings Figure A-2, Log of Boring B 2, Page 1 of I SAMPLE SYMBOLS H ... SAMPLING UNSUCCESSFUL I. ... STANDARD PENETRATION TEST U ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE Y ...WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GE000N PROJECT NO. G1076-42-01 BORING ZLIJ DEPTH SAMPLE o SOIL FEET NO. ELEV. (MLLW.) 53' DATE COMPLETED 02-03-2009 0 EQUIPMENT IR-300 BY: N.N. BORJA 0 0 MATERIAL DESCRIPTION - ASPHALT CONCRETE 21/2 inches \ BASE 4 inches SM UNDOCUMENTED FILL Medium dense to dense, moist, dark reddish brown to dark brown, Silty, fine 2 \ to medium SAND; trace gravel -tIT. - SM TERRACE DEPOSITS 133-1 50 - Dense, damp to moist, mottled reddish brown and yellowish brown, Silty, fine to medium SAND; some mica and manganese B3-2 4 . i. - 133-3 -Becomes very dense, mottled reddish brown and grayish brown to olive 69 brown 6 -8- 10 B34 . . -Becomes dense, very moist, grayish brown to brown - 44 B3-5 H I -Seepage at II feet 12 B3-6 . -No recovery 57 BORING TERMINATED AT 13 FEET Seepage encountered at II feet Backfilled with bentonite chips and drill cuttings Figure A-3, . G1076-42-01.GPJ Log of Boring B 3, Page 1 of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL STANDARD PENETRATION TEST U ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE V ... WATER TABLE OR SEEPAGE NOTE THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GEOCON PROJECT NO. G1076-42-01 BORING B4 > z 2o— >- uJ DEPTH SAMPLE SOIL - I- Z CI) (I) -' IX H Z IN FEET NO, O CLASS ELEV. (MLLW.) 53 DATE COMPLETED 02-03-2009 i- (USCS) EQUIPMENT IR-300 BY: N.N. BORJA 0 CC 0 _____ _____ MATERIAL DESCRIPTION UI - ASPHALT CONCRETE 2¼ inches SM BASE 4 inches UNDOCUMENTED FILL Loose, moist, dark brown, Silty, fine to medium SAND; trace gravel 2 134-I 27 134-2 7T - CL TERRACE DEPOSITS • Firm to stiff, moist, dark grayish brown to olive brown, Sandy CLAY • 134-3 -. • _______ - SM - Medium dense, moist, grayish brown, Silty, fine to medium SAND BORING TERMINATED AT 5 FEET No groundwater encountered --------- 24 Backfilled with cuttings Figure A-4, G107642-01.GPJ Log of Boring B 4, Page 1 of I SAMPLE SYMBOLS ... SAMPLING UNSUCCESSFUL I .. STANDARD PENETRATION TEST •.. DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE • ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GEOCON PROJECT NO. G1076-42-01 BORING B5 zLu . >- DEPT < SOIL <<U) 1) uJ IN SAMPLE NO. CLASS ELEV. (MLLW.) 52' DATE COMPLETED 02-03-2009 0 LU FEET EQUIPMENT IR-300 BY: N.N. BORJA O MATERIAL DESCRIPTION 0 ASPHALT CONCRETE 2/2 inches SM - - BASE 4 inches UNDOCUMENTED FILL Medium dense, moist, dark brown, Silty, fine to medium SAND; trace gravel - 2 - - 135-1 'i. 29 CL TERRACE DEPOSITS I .. Firm to stiff, moist, grayish brown to olive brown, Sandy CLAY -4 - - 135-2 / -Becomes hard -57 6 - B5-3 8 • t 7/ 10 48 SM Dense, damp to moist, light gray to grayish brown, Silty, fine to medium 135-5 I SAND; some mica and manganese — 12 - 14 135-6 -Becomes very moist, fine- to coarse-grained - 56 BORING TERMINATED AT 15 FEET No groundwater encountered Backfilled with bentonite chips and drill cuttings Figure A-5, Log of Boring B 5, Page 1 of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL Ii.. STANDARD PENETRATION TEST I ... DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ••. CHUNK SAMPLE V •.. WATER TABLE OR SEEPAGE NOTE. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. GE000N PROJECT NO. G1076-42-01 LU BORING B6 2W LD _ W DEPTH SAMPLE < SOIL I— Z U)cr IN NO. X z ELEV. (MLLW.) 51 DATE COMPLETED 02-03-2009 LU LU FEET o EQUIPMENT IR-300 BY: N.N. BORJA a. MATERIAL DESCRIPTION ASPHALT CONCRETE 2% inches SM - BASE 4 inches UNDOCUMENTED FILL 1, Loose to medium dense, moist, dark brown. Silty, fine to medium SAND; 2 trace gravel B6-1 34• 136-2 H - SM TERRACE DEPOSITS Dense, moist, dark reddish brown to brown, Silty, fine to medium SAND .4. B6-3 -Becomes medium dense 22 -6- 8 -Becomes dense, damp to moist, yellowish brown to reddish brown' some 10 B64 - mica and manganese - 31 BORING TERMINATED AT 101/2 FEET No groundwater encountered Backfilled with drill cuttings Figure A-6, Log of Boring B 6, Page l of I SAMPLE SYMBOLS SAMPLING UNSUCCESSFUL U STANDARD PENETRATION TEST U DRIVE SAMPLE (UNDISTURBED) DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE V....WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. - GEOCON APPENDIX APPENDIX B LABORATORY TESTING We performed laboratory tests in accordance with generally accepted test methods of the American Society for Testing and Materials (ASTM) or other suggested procedures. Selected samples were tested to evaluate compaction (maximum dry density and optimum moisture content), expansion characteristics, direct shear strength, and water-soluble sulfate content. The results of the laboratory tests are summarized in Tables B-I through B-TV. TABLE B-I SUMMARY OF LABORATORY MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT TEST RESULTS ASTM D 1557-02 Sample No. escription Description Maximum Dry Density (pci) Optimum Moisture Content (% dry wt.) 132-1 Dark brown, Silty, fine to coarse SAND; trace gravel 134.9 8.2 133-2 Yellowish brown, Silty, fine to medium SAND 134.3 7.8 TABLE B-It SUMMARY OF LABORATORY DIRECT SHEAR TEST RESULTS ASTM 0 3080-03 Sample Dry Density Moisture Content (%) Unit Cohesion Angle of No. (pci) (psi) Shear Resistance Initial Final (degrees) 133-1 113.2 6.8 13.8 1180 38 TABLE B-Ill SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS ASTM D 4829-03 Sample No. Moisture Content (%) Dry Density (pci) Expansion Index Before Test After Test 132-1 7.5 12.4 119.1 2 135-3 9.1 22.6 111.1 88 Project No. G1076-42-01 . - B-I - February 24, 2009 TABLE B-IV SUMMARY OF LABORATORY WATER-SOLUBLE SULFATE TEST RESULTS CALIFORNIA TEST NO. 3417 Sample No. Water-Soluble Sulfate (% SO4) Sulfate Exposure B2-1 0.038 Negligible B5-3 0.005 Negligible Project No. G1076-42-01 . - B-2 - February 24, 2009 APPENDIX APPENDIX C C' EXPLORATORY BORING LOGS AND LABORATORY TEST DATA PERFORMED BY LEIGHTON & ASSOCIATES FOR CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PROJECT NO. G1076-42-01 GEOTECHNICAL BORING LOG KEY Date Project KEY TO BORING LOG GRAPHICS Drilling Co. Hole Diameter Drive Weight Elevation Top of Hole +1- ft. Ref. or Datum Sheet 1 of 1 Project No. Type of Rig Drop C d o 4- ' L GEOTECLINICAL DESCRIPTION . .O 4- z OLL C9- WO 4- j m.i L 0 Z - co. CD ' Logged By Sampled By U CO 0 CL Inorganic clay of low to medium plasticity; gravelly clay; sandy clay; silty clay; lean clay Inorganic clay or high plasticity; fat clay CH OL-OH Organic clay, silt or silty clay-clayey silt mixtures • SF1' SAMPLE ML Inorganic silt; very fine sand; silty or clayey fine sand; clayey silt with low plasticity MH Inorganic silt; diatomaccous fine sandy or silty soils; elastic silt CAL SAMP E CL-MI., Low plasticity clay to silt mixture ______ ML-SM Sandy silt to silty sand mixture CL-SC Sandy clay to clayey sand mixture SC-SM Clayey sand to silty, sand mixture to— SW Well graded sand; gravelly sand, little or no fines SP Poorly graded sand; gravelly sand, little or no fines SM - Silty sand; poorly graded sand-silt mixture Sc Clayey sand; poorly graded sand; clay mixture GW Well graded gravel; gravel-sand mixture, lime or no fines GP Poorly graded gravel; gravel-sand mixture, little or no fines GRC L ND WA TFR AT I ME 15—E15—TA 01 DRIL1.1 4G GM Silty gravel; gravel-sand-silt mixture OC Clayey gravel; gravel-sand-clay mixture Sandstone - Siltstone - ______ Claystone 20— - Breccia (angular gravel and cobbles 'or matrix-support conglomerate) Conglomerate (rounded gravel and cobble clast-supported) - Igneous granitic or granitic type rock - Metavolcanic or metamorphic rock 25— Artificial or man-made fill _______ Asphaltic concrete Portland cement concrete - In - = 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-i Date 3-7-01 Sheet I of 2 Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type. of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds Drop .Q_ in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level w >I w fg' i..J f 0 Z w , - L ao. a .- _OJ u d j LO ' GEOTECHNICAL DESCRIPTION Logged By AXT Sampled By AXT 50.0— Bag- I - - @0': 4' Asphalt Concrete over 5' Base @0-5 SM ARTIFICIAL FILL 2': Silty fine SAND: dark brown to brown, moist, medium dense; contact with 1 17 Terrace Deposits @3' SM TERRACE DEPOSITS 45 2 44 110.6 13.0 SM-SC @5': Silty fine to medium SAND: red-brown to brown, moist, medium dense; / slightly cemented; slightly clayey 40 10-- 3 50 SM-SC @ 10': Silty fine to medium SAND: dark brown, moist, medium dense; slightly - -: clayey - / © 13': Groundwater encountered 35 15—. .-. '. 4 55 105.0 20.4 SW @ 15,: Well-graded fine to coarse SAND: brown, wet, medium dense; 2-112 -. rounded gravel in shoe SW SAN'IlAGOFORMATIN 30 20 5 95 SM © 20': Silty fine to coarse SAND: grayish-brown, moist to wet, medium dense 25 25— : 6 50/4W 120.2 12.4 SM @25': Silty fine to coarse SANDSTONE: grayish-brown, moist, very dense; _2 moderately cemented 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHMCAL BOEING LOG B-i Date 3-7-01 Sheet 2 of 2 Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig -61 Hole Diameter Sin Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level GEOTECHNICAL DESCRIPTION i j . E j Z Logged By AXT U' C Sampled By AXT 20 3 DI ' 'M @ 30: Same as previous Total Depth = 30,4 Feet Ground water encountered at 13 feet - Backfihled with cuttings, bentonite, and concrete on 3/7/01 Capped with 2 to 3 inches asphalt concrete 15 35- 10 40- 5- 45— o 50- -5 55- ml- - -io~ 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNICA.L BORING LOG B-2 Date 3-7-01 Sheet 1 of 1 Project CarltaslCarlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter 8 in Drive Weight 140 pounds Drop .30 in. Elevation Top of Hole +1- 48 ft. Ref. or Datum - Mean Sea Level GEOTECHNICAL DESCRIPTION 4.4" 01 4..+' a_U . £0) a_a 01 -*- 30 o wu c - o >., 0) 45J 0 Z — C) Q. ._01 U) !'- j Logged By AXT Li - (0 (flS Sampled By AXT 0 — Bag-2 - @0-4': Asphalt Concrete -- - - - - - - - - - - - - - - - - - - - - - - - • 1 i .I• SM AR'FIFICIAL FILL @ 8": Silty fine to coarse SAND: gray-brown, dry, medium dense; possibly -. - , granite - I I '45-RESIDUAL 28 112.4 13.0 CH 7 decomosed SOIL CLAY: dark gmyish-gmen, moist, very stiff; slightly organic :5i - : 2 28 SM-SC TERRACE DEPOSITS © 5': Silty fine to medium SAND: reddish-brown to gray-brown, moist, medium dense; slightly clayey 40 -H 3 39 97.7 8.6 SP @ 10': Poorly-graded fine SAND: brown, moist, medium dense; slightly silty 35 - 15— :: 4 44 SP © 15': Same as previous; dense 30. :- SM-SC SANTIAGO FORMATION - 20— :2 •• 5 77 @ 20': Silty fine SAND: reddish-brown to grayish-green, very dense; slightly - : 4': oxidized; slightly clayey 25 25— ':: - 6 64/6" SW @25': Well-graded medium to coarse SAND: light brown, moist, very dense. \ moderately cemented Total Depth = 25.5 Feet - Ground water encountered at 14 feet at time of drilling Backfillcd with soil cuttings on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 20 —in 1 = = 505A01/77, LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-3 Date 3-7-01 Sheet 1'of 1 Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter Sin Drive Weight 140 pounds Drop 30 in. Elevation Top of Hole +1- 47 ft. Ref. or Datum - Mean Sea Level GEOTECHNICAL DESCRIPTION - • . -C.g' . 0, Logged By AXT Ui • - C,' '. 0 (' Sampled By. AXT 0— g-3 - - ( 0-35W: Asphalt Concrete SM ARTIFICIAL FILL - .H.@ 7*: Silty fine SAND: brown, moist • . : / 1 37 116.5 14.9 SM-SC TERRACE DEPOSITS @2.5': Silty clayey SAND: gray-brown to red-brown and white, moist, medium . . dense; calcium carbonate blebs visible 2 22 SM © 5': Silty fine SAND: grayish-brown, moist, medium dense 40 10— 3 78 120.9 15.0 @ 10': Same as previous; dense 35 :- -15 4 77 © 15': Silty fine to medium SAND: reddish-brown to gray, moist to wet, very dense; I/4 to I/2 subangular gravels common 30- - 20—-.- 5 73 SM SANTIAGOFORMA11ON @ 20': Silty fine to SAND: brown to greenish-brown, moist, very dense; few fine gravels; moderately cemented 25 - Total Depth 21.5 Feet Ground water encountered at 14 feet at time of drilling - Backlilled with soil cuttings on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 25- 20 - 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNICAL BORING LOG B-4 Date 3-7-01 Sheet .J_ of I Project Caritas/Carisbad Office Campus Project No. _0382-001 Drilling Co. F&C Drilling Type of Rig B-1 Hole Diameter 8 in Drive Weight 140 pounds Drop _10 in. Elevation Top of Hole +1- 47 ft., Ref. or Datum - Mean Sea Level o GEOTECILNICAL DESCRIPTION Logged By AXT LU (1) 0 C-) (1)" Sampled By AXT 0 - Bag-4 - - - @0-3": Asphalt Concrete / 45 - -1 ARTIFICIAL FILL @6':Silty fine SAND:lightbrown,rnoist :• - SM TERRACE DEPOSITS I 47 116.8 15.9 SM-SC @ 5': Silty clayey fine SAND: red-brown to gray-brown, moist, medium dense; - calcium carbonate blebs visible 40 10 . 2 31 SM-SC @ 10': Silty fine SAND: gray-brown, moist, medium dense; slightly clayey 35 15 3 58 107.8 20,4 SP @ 15': Poorly-graded fine to medium SAND: grayish brown, moist to wet, . -• :-. • , medium dense; thin beds of medium to coarse SAND; slightly micaceous; - : .: =- slightly silty 30 - : 20.---: 4 70/6" - -SP ------------- SANTIAGOFORMATION- - - @ 20': Silty fine SAND: light grayish brown, moist, very dense; moderately - t cemented Total Depth = 20.5 Feet - Ground water encountered as 16 feet at time of drilling Backfilled with soil cuttings on 3/7/01 - Capped with 2 to 3 inches asphalt concrete 25- 20 - 505A(11177). LEIGHTON & ASSOCIATES GEOTECLINICAL BORING LOG B-S Date 3-7-01 Sheet jjof —j._ Project Caritas/Carlsbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter S in Drive Weight 140 pounds Drop ..30 in. Elevation Top of Hole +1-. 50 ft. Ref. or Datum Mcan Sea Level GEOTECHNICAL DESCRIPTION .IV I . W 3 1 cc* — > ;•I 44- IV ' Logged By AXT - Sampled By AXT - C3 C) C 50- 0 . 3g-5 - @0-3.5" Asphalt Concrete '35'-7i:_AJ&re.p_tese SP ARTIFICIAL FILL - - - - © 8.5': Silty. fine SAND: brown, moist SP TERRACE DEPOSITS 45. .:5 1 29 106.2 5.5 @5': Poorly-graded fine SAND: red-brown to brown, moist, medium dense; slightly silty .-4O lO 2 32 -- Sp @ 10': Poorly-graded fine SAND: gray to orange, moist, dense; slightly oxidized 3 80110' 112.2 17.4 SW @ 15: Well-graded fine to coarse SAND: light brown, wet, very dense 30 20— 4 97 TC SNT1AGOFORMAfl6N - A0 21': SILTSTONE: grayish brown, dry to slightly moist, very stiff - Total Depth = 21.5 Feet - Ground water encountered at 14.5 feet at time of drilling Backfitled with soil cuttings on 3/7/01 - - Capped with 2 to 3 inches asphalt concrete 25 ......2Q. 25— In 505A(11/77) LEIGHTON & ASSOCIATES GEOTECHNECAL BORING LOG B-6 Date 3701 Sheet 1 of 1 Project Carltas/Carisbad Office Campus Project No. 040382-001 Drilling Co. F&C Drilling Type of Rig B-61 Hole Diameter S in Drive Weight 140 pounds Drop in. Elevation Top of Hole +1- 50 ft. Ref. or Datum Mean Sea Level 1 to GEOTECHNICAL DESCRIPTION rd W .cCJ) ci C'4- 0. di Logged By AXT cn j (fl" Sampled By AXT 50- 0 - - - - - @ 0-2.5': Asphalt Concrete 2.5"6.5AJ&reJateBase 'S SM A RTIFICIAL FILL @ 6.5': Silty tine SAND: Mottled dark brown to brown, moist, medium dense -I 1 40 120,4 12.8 SP TERRACE DEPOSITS @5.5': Contact with Terrace Deposits @6': Poorly-graded fine SAND: reddish-brown, moist, medium dense 40 10— 2 27 SP @ 10': Same as previous 35 15 3 80 110.7 20.4 SP @ 15': Poorly-graded tine to medium SAND: brown, wet, dense; slightly silty - :. •': . 104.6 20.2 30 20— :f":'! 5 70/10 ANTIAöói95N------------------------ FORMA @20': Well-graded fine to coarse SAND: light brown, wet, very dense Total Depth = 21.5 Feet Ground water encountered at 17 feet at time of drilling - Backfilled with soil cuttings on 3(1101 - Capped with 2 to 3 inches asphalt concrete 25 25— = 505A(11/77) LEIGHTON & ASSOCIATES 040382-001 APPENDIX C Laboratory Testing Procedures and Test Results Chloride Content: Chloride content was tested in accordance with DOT Test Method No. 422. The results are presented below: Sample Location Chloride Content, ppm Chloride Attack Potential* B- 1, 0-5 Feet 170 Threshold B-3, 0-5 Feet --- 350 Positive *per City of San Diego Program Guidelines for Design Consultant, 1992. Consolidation Tests: Consolidation tests were performed on selected, relatively undisturbed ring samples in accordance with Modified ASTM Test Method D2435. Samples were placed in a consolidometer and loads were applied in geometric progression. The percent consolidation for each load cycle was recorded as the ratio of the amount of vertical compression to the original I-inch height. The consolidation pressure curves are presented on the attached figure. Direct Shear Tests: Direct shear tests were performed on selected remolded and/or undisturbed samples which were soaked for a minimum of 24 hours under a surcharge equal to the applied normal force during testing. After transfer of the sample to the shear box and reloading of the sample, the pore pressures set up - - in the sample (due to the transfer) were allowed to dissipate for a period of approximately 1 hour prior to -app licátion of shearing force. The-samples were tested under various normal loads utilizing a motor-driven, 'strain-controlled, direct-sheaf testing apparatus at a strain rate of less than 0.001 to 0.5 inches per minute (depending upon the soil type). After a "peak" value of shear strength was observed or after a shear strength Was observed or after a shear strain of 0.2 inches if no peak was observed, the motor was stopped and the saniple was allowed to "relax" for approximately 15 minutes. The stress drop during the relaxation period -. was recorded. It is anticipated that, in a majority of samples tested, the 15 minutes relaxing of the samples r is -sufficient to allow dissipation of pore pressures that may have set up in the samples due to shearing. The drained peak strength was estimated by deducting the shear force reduction during the relaxation period -from the peak shear values. The shear values at the end of shearing are "ultimate" values. The drained peak strengths are presented in the test data. Friction Angle Apparent Sample Location - - Sample Description Test Type (degrees) Cohesion (psf) B-2, Ii Feet Brown poorly-graded fine sand Undisturbed 33 140 B4,6 Feet Red-brown to gray-brown silty Undisturbed 30 1020 clayey sand c-I 040382-001 APPENDIX C (continued) Hydrocollapse: Selected samples were loaded in a consolidometer to the proposed overburden pressure. The samples were then inundated with water and the percent hydrocollapse was measured and recorded below. Sample Location % Hydrocollapse B-6, 6 Feet I 0.2 @ 700 psf Expansion Index Tests: The expansion potential of selected materials was evaluated by the Expansion Index -. Test U.B.C. Standard No. 18-2. Specimens are molded under a given compactive energy to approximately the optimum moisture content and approximately 50 percent saturation or approximately 90 percent relative compaction. The prepared 1-inch thick by 4-inch diameter specimens are loaded to an equivalent 144 psf surcharge and are inundated with tap water until volumetric equilibrium is reached. The results of these tests are presented in the table below: V Compacted Dry Expansion Expansion Sample Location Sample Description Density (pet) Index Potential B-i, 0-5 Feet Brown silty sand 120.8 2 Very Low B-3 0-5 Ft Gray brown silty clayey 114.4 56 Medium V sand V ' Moisture and Density Determination Tests: Moisture content and dry density determinations were performed Ofl relatively undisturbed samples obtained from the test borings. The results of these tests are 'piesented in the boring logs. Where applicable, only moisture content was determined from "undisturbed" or disturbed samples. Minimum Resistivity and pH Tests: Minimum resistivity and pH tests were performed in general V accordance with California Test Method 643. The results are presented in the table below: Sample V Sample Location Description pH Minimum Resistivity (ohms-cm) B-I, 0-5 Feet Brown silty sand 7.2 4600 B-3, 0-5 Feet Gray brown silty clayey 8.0 890 sand C-2 040382-001 APPENDIX C (continued) Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard geochemical methods. The test results are presented in the table below: Sample Location Sulfate Content (%) Potential Degree of Sulfate Attacks B- 1, 0-5 Feet 0.018 Negligible B-3, 0-5 Feet 0.020 - - Negligible * Based on the 1997 edition of the Uniform Building Code, Table No. 19-A4, prepared by the International Conference of Building Officials (ICBO, 1997). "R"-Value: The resistance "R"-value was determined by the California Materials Method No. 301 for base, subbase, and basement soils. The samples were prepared and exudation pressure and "R"-value determined. The graphically determined "R"-value at exudation pressure of 300 psi is reported. Location Design R-Value B-3, 0-5 Feet 21 C-3 APPENDIX APPENDIX D - RECOMMENDED GRADING SPECIFICATIONS FOR CARLSBAD OFFICE CAMPUS 5600 AVENIDA ENCINAS CARLSBAD, CALIFORNIA PROJECT NO. G1076-42-01 LIST OF REFERENCES Boore, D. M., and G. M Atkinson (2006), Boore-Atkinson NGA Ground Motion Relations Jbr the Geometric Mean Horizontal Component of Peak and Spectral Ground Motion Parameters, Report Number PEER 2007/01, May 2007. California Department of Conservation. Division of Mines and Geology, Probabilistic Seismic Hazard Assessment fbr the State of California, Open File Report 96-08, 1996. California Geological Survey, Seismic Shaking Hazards in California, Based on the USGS/CGS Probabilistic Seismic Hazards Assessment (PSHA) Model, 2002 (revised April 2003). 10% probability of being exceeded in 50 years. httix//redirect.conservation.ca.gov/cgs/rghni/psharnap/pshamain.litnil Campbell, K. W., Y. Bozorgnia, NGA Ground Motion Model for the Geometric Mean Horizontal Component of PGA, PGV, PGD and 5% Damped Linear Elastic Response Spectra for Periods Ranging from 0.01 to 10 s, Preprint of version submitted for publication in the NGA Special Volume of Earthquake Spectra, Volume 24, Issue 1, pages 139-171, February 2008. Kennedy, M. P. and S. S. Tan, 2005, Geologic Map of the Oceanside 30'x60' Quadrangle, California, USGS Regional Map Series Map No. 3, Scale 1:100,000. K&S Engineering, Tentative Map for Carlsbad Office Campus, Sheet TM-I, Carlsbad, calfbrnia, revision date March 26, 2004 (Job No. 01-048). Leighton & Associates, Geotechnical Investigation for Proposed Carlsbad Office Campus, 5600 Avenida Encinas, Carlsbad, (aliJbrnia, dated April 2, 2001 (Project No. 040382-001). Geology of San Diego Metropolitan Area, California, California Division of Mines and Geology, Bulletin 200, 1975, Jennings, C. W., 1994, California Division of Mines and Geology, Fault Activity Map of c'alifornia and Adjacent Areas, California Geologic Data Map Series Map No. 6. United States Geological Survey, 7.5 Minute Quadrangle Series, Encinitas, 1967. Risk Engineering, EZ-FRISK, 2008. USGS computer program, Seismic Hazard Curves and Uniform Hazard Response Spectra. Project No. G1076-42-0I February 24, 2009