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HomeMy WebLinkAbout3190; Rancho Sante Fe Road Realignment; Rancho Sante Fe Road Realignment; 2000-07-01I. T D.TAM OU E GEOTECHNICAL DESIGN REPORT RANCHO SANTA FE ROAD REALIGNMENT STATION 252+00 TO MELROSE DRIVE CARLSBAD, CALIFORNIA PREPARED FOR DOKKEN ENGINEERING SAN DIEGO, CALIFORNIA JULY 2000 tti GEOCON INCORPORATED GEOTECHNICAL CONSULTANTS ProjectNo. 06535-22-01 July 17,2000 ll m Dokken Engineering 3914 Murphy Canyon Road, Suite A-153 San Diego, CaUfomia 92123-4491 Attention: Subject: Mr. Kirk Bradbury RANCHO SANTA FE ROAD REALIGNMENT STATION 252+00 TO MELROSE DRIVE CARLSBAD, CALIFORNIA GEOTECHNICAL DESIGN REPORT Gentlemen: m m In accordance with your authorization of our proposal LG-00340 dated May 31, 2000, we herein submit the results of our geotechnical design investigation for the proposed realignment of Rancho Santa Fe Road from approximately Station 252+00 to Melrose Drive in eastem Carlsbad, Califomia. The accompanying report presents the fmdings and conclusions from our study. Based on tiie results of our study, it is our opinion that the realignment can be constmcted as proposed, provided the recommendations of this report are followed. If you have any questions regarding this investigation, or if we may be of fiirther service, please contact the undersigned at your convenience. Very tmly yours, GEOCON INCORPORATED Joseph J. Vettel GE 2401 JJV:PD:lek (6/del) Addressee Paul Dunster RG 6761 6960 Flanders Drive • San Diego, California 92121-2974 • Telephone 1858) 558-6900 • Fax (858) 558-6159 «• TABLE OF CONTENTS pi 1. PURPOSE AND SCOPE 1 IK 2. SITE AND PROJECT DESCRIPTION 2 P 3. SOIL AND GEOLOGIC CONDITIONS 2 3.1 Undocumented Fill 2 3.2 Topsoil 3 3.3 Alluviimi 3 3.4 Granitic Rock 3 4. GROUNDWATER 3 m h m k 5. GEOLOGIC HAZARDS 4 ^ 5.1 Landslides 4 te* 5.2 Faulting 4 5.3 Soil Liquefaction Potential 5 P 5.4 Tsunamis and Seiches 5 in 6. CONCLUSIONS AND RECOMMENDATIONS 6 P 6.1 Earthwork 6 il 6.2 Grading 6 6.3 Settlements 7 * 6.4 Slopes 7 ^ 6.5 Earthwork Quantities 8 6.6 Excavation and Soil Characteristics 9 ^ 6.7 Retaining Walls 9 ^ 6.8 Preliminary Pavement Recommendations 10 6.9 Corrosion 11 ^ 6.10 Culverts 11 ^ 6.11 Geotechnical and Constmction Review 11 ^ LIMITATIONS AND UNIFORMITY OF CONDITIONS MAPS AND ILLUSTRATIONS Figure lA, Vicinity Map Figures 1-12, Log of Test Borings APPENDDCA FIELD INVESTIGATION Figures A-l—A-4, Logs of Borings Figures A-5—A-21, Logs of Trenches f TABLE OF CONTENTS (continued) li F APPENDIXB li LABORATORY TESTING Table B-I, Summary of Direct Shear Test Results E Table B-II, Summary of Maximimi Dry Density and Optimum Moisture Content Test Results Table B-III, Summary of Laboratory Expansion Index Test Results E Table B-IV, Summary of Laboratory Resistance Value Test Results Table B-V, Summary of Laboratory Water Soluble Sulfate Test Results Table B-VI, Summary of Chloride Ion Content Test Results fp Table B-Vn, Summary of Laboratory pH and Resistivity Test Results il Figure B-1, Gradation Curve Figure B-2 and B-3, Consolidation Curve APPENDIX C GRADING SPECIFICATIONS APPENDIXD SEISMIC REFRACTION SURVEY DATA P ^ LIST OF REFERENCES Ml m ^ GEOTECHNICAL DESIGN REPORT tti E 2 1. PURPOSE AND SCOPE This report presents the results of a geotechnical design investigation for the proposed realignment of Rancho Santa Fe Road from Station 252+00 at the south end to Melrose Drive at the north, located in eastem Carlsbad, Califomia (see Vicinity Map, Figure 1). The purpose of the investigation was to identify the site geology, to observe and sample the prevailing soil conditions at the site and, based on the conditions encountered, to provide recommendations relative to earthwork and pavement support of the road realignment as proposed. A stmcture foundation investigation is being performed concurrently for the planned bridge on the portion of the alignment over San Marcos Creek. Previous investigations for the proposed alignment and bridge were reviewed in preparing this report including: • Supplemental Soil and Geologic Investigation for Rancho Santa Fe Road Re-alignment. prepared by Geocon Incorporated, dated January 8, 1990. W • Bridge Foundation Investigation for Rancho Santa Fe Road Re-alignment, Rancho Santa Fe in Bridge Crossing at San Marcos Creek, Carlsbad, California, prepared by Geocon hicorporated, dated September 13, 1990. P •I • Supplemental Geotechnical Investigation Report, Design Stage 2, Rancho Santa Fe Road, South of Station 252, Carlsbad, California, prepared by AGRA Eardi & Environmental, pi dated November 10, 1998, revised April 30, 1999. h The scope of our Geotechnical Design Report investigation included a site reconnaissance, a field investigation including exploratory borings and trenches, laboratory testing, engineering analyses and preparation of this report. The field investigation was performed on June 21 through 23, 2000, and consisted of the excavation of 17 test trenches and 4 test borings. Ten air track borings, nine small-diameter borings and eight trenches from the previous geotechnical investigations excavated |M in the general vicinity of the realignment are also included. Logs of the borings and trenches and ii other details ofthe current field investigation are presented in Appendix A and all boring and trench data from current and previous investigations is presented on the Log of Test Borings (Figures 2 ^ through 15, Map Pocket). Data from two seismic refraction surveys performed during previous investigations are presented in Appendix D along with station and offsets for reference to locations. Laboratory tests were performed on selected soil samples obtained from the exploratory borings to fiAm determine their pertinent physical and chemical properties for engineering analyses. A discussion tta pertaining to the laboratory testing and results is presented in Appendix B. Project No. 06535-22-01 - 1 - July 17, 2000 m it The recommendations presented herein are based on an analysis of the data obtained from the exploratory excavations, laboratory tests, and our experience with similar soil and geologic conditions. 2. SITE AND PROJECT DESCRIPTION The proposed realignment of Rancho Santa Fe Road generally extends along the east side of the existing road alignment. At the south end of the alignment to San Marcos Creek the ground surface generally slopes downward to the east and north and is covered by sparse vegetation. A small canyon drains to the east at approximately the intersection of Questhaven Road and Rancho Santa Fe Road. It is expected that drainage facilities will be necessary at this location. From the creek area to the north is relatively flat with commercial development east of the existing roadway. At the south end of the alignment, cut slopes up to about 30-foot high will be made to achieve grades. Fills will be necessary on both sides of the proposed alignment at the location of the east- west trending canyon near Questhaven Road. A new right and left bridge will span San Marcos Creek from about Station 270+00 to 274+00. North of the creek, the new roadway will be at approximately existing grade. Ground surface elevations range from about 450 feet on the westem side of the alignment near its south end to 320 feet mean sea level (MSL) within the active channel of San Marcos Creek. Final grading plans were not available for review; however, it is anticipated that site grading operations will consist of the maximum cuts of about 30 feet at the south end and fills with a maximum thickness of about 20 feet at the bridge abutments and near the existing intersection of Questhaven Road and Rancho Santa Fe Road. 3. SOIL AND GEOLOGIC CONDITIONS In general, the field investigation indicated that subsurface conditions are variable along the bridge iw alignment. In general, the site is underlain by fill, topsoil, alluvium and granitic rock. The soil and/or ll rock conditions encountered are described in detail below. m to 3.1 Undocumented Fill ^ Undocumented fill soils were encountered in several of the trenches and borings. Roadway fill at the ^ intersection of Questhaven Road and Rancho Santa Fe Road placed to fill a small canyon were ^ typically on the order of 2 to 5 feet thick and are characterized as loose to moderately dense clayey ProjectNo. 06535-22-01 ~- July 17,2000 ^ and silty sand and clayey gravel. The undocumented fill soils are not adequate in their present condition for support of settlement sensitive structures of stmctural fill. Therefore, complete removal fH and recompaction should be performed in accordance with the recommendations in the Grading to portion of this report. y 3.2 Topsoil ^ Topsoil was encountered throughout the alignment mantling the granitic and volcanic rock. In Mi general, the topsoil consists of 1 to 2 feet of loose, dry silty sand and sandy silt. Topsoils are also ^ inadequate in their present condition for support of settlement sensitive stmctures or stmctural fill. ^ Accordingly, complete removal and recompaction should be performed in accordance with the recommendations in the Grading portion ofthis report. to 3.3 Alluvium tm Alluvial soils were encountered at the surface within the majority of the low-lying portions of the San Marcos Creek channel and north to the project limits. The alluvial soils are characterized as ^ loose to moderately dense, moist to saturated, dark brown silty and clayey sands with some gravel, cobble and boulders. The thickness of the alluvium encountered within the current and previous exploratory excavations ranged from approximately 1 to 14 feet. Complete removal ofthe alluvium ^ at the bridge abutments should be performed prior to placement ofthe approach embankments. ^ 3.4 Granitic Rock ^ Cretaceous-aged granitic rock correlated to the Bonsall Tonalite or Escondido Creek Granodiorite of to the Southem Califoraia Batholith comprises the bedrock material underlying the alignment. The weathered granitic rock is characterized by a dense to very dense, light brown, weathered to highly weathered rock that excavates to a fine- to coarse-grained sand with gravel, cobble and boulder-size fragments. In the river channel, the depth to the weathered granitic rock is up to 14 feet from the existing ground surface. Throughout the remainder ofthe alignment, granitic rock was encountered at depths ranging from about 2 to 7 feet. The rock becomes less weathered with depth and rippability ^ will be an important consideration in constmction of the project. Rippability will be addressed in ito subsequent sections of this report. 4. GROUNDWATER Groundwater was present at a depth of approximately 2 feet below the ground surface in the San Marcos Creek channel. No groundwater was encountered north or south of the creek area. ProjectNo. 06535-22-01 ~ July 17,2000 to to to to Dewatering during removal and recompaction of the existing alluvium at the bridge abutments and to facilitate the foundation excavations and permit the foundations to be constmcted in a dry environment will likely be necessary. Well points or other dewatering methods should be installed by the contractor to insure that all of the excavations remain free of standing water throughout constmction. 5. GEOLOGIC HAZARDS 5.1 Landslides No landslides were encountered during the site investigation or are known to exist within the limits of the proposed realignment. 5.2 Faulting No active faults or potentially active faults are known to exist at the site. The Rose Canyon Fault is the nearest active fault and lies approximately 8 miles west of the site. The known active or potentially active faults within a (62-mile) 100 kilometer radius of the site as identified in the Califomia Seismic Hazard Map (1996) published by Caltrans are indicated in Table 5.2. Associated maximum credible earthquake magnitudes and peak horizontal bedrock accelerations are also presented in Table 5.2. to h TABLE 5.2 DETERMINISTIC SITE PARAMETERS FOR SELECTED ACTIVE FAULTS Fault Name Distance From Site (miles) Maximum Credible Event Fault Name Distance From Site (miles) Magnitude Peak Site Acceleration (g) Newport-lnglewood-Rose Canyon/East 8 7.0 0.32 Palos Verdes Hills-Coronado Bank 23 7.75 0.23 Whittier-Elsinore 24 7.5 0.17 San Diego Trough 34 7.5 0.12 Casa-Loma-Clark (San Jacinto Zone) 48 6.75 0.05 San Clemente 60 7.25 0.05 Project No. 06535-22-01 -4-July 17, 2000 1* Peak horizontal acceleration values were developed from various sources (Slemmons, 1982; EQFAULT, 1993) in addition to Mualchin's Caltrans Califomia Seismic Detail Index Map, 1996. A E peak acceleration of 0.32g is in good agreement with the value obtained from the Califomia Seismic Detail Index Map, 1996. 2 It is our opinion that the site could be subject to moderate to severe ground shaking in the event of an earthquake along any of the faults listed in Table 5.2 or other faults in the southem P Califomia/northem Baja Califomia region. However, we do not consider the site to possess any greater risk than that of the surrounding developments. Parameters for design in accordance with 01 Caltrans criteria are presented in Section 6.2.6. to to 5.3 Soil Liquefaction Potential Soil liquefaction occurs within relatively loose, cohesionless sands located below the water table that to are subjected to ground accelerations from earthquakes. The only soils below groimdwater levels i* will be in the active channel of San Marcos Creek. Pier footings will extend into dense granitic rock and liquefaction of alluvial soils adjacent to the piers is considered insignificant to the performance |y of the pier foundations. Alluvial soils will be removed and replaced with compacted fill within the abutment areas of the bridge and dense granitic rock is relatively shallow throughout the remainder to of the site. Therefore, the potential for liquefaction occurring throughout the alignment, except to within the active channel, is considered low. ^ 5.4 Tsunamis and Seiches The site is not located near the ocean, so tiiere is no risk of tsunamis affecting the site. Lake San *** Marcos is several miles upstream from the proposed bridge. Seiches could be generated in a seismic event ifthe reservoir is full or nearly full. However, the bridge will be supported in granitic rock and iw it is estimated that no significant damage would occur in the event of limited overtopping. to Project No. 06535-22-01 - 5 - July 17, 2000 ii 6. CONCLUSIONS AND RECOMMENDATIONS ii P 6.1 Earthwork 6.1.1 From a geotechnical standpoint, it is our opinion that the site is suitable for the proposed W realignment, provided the recommendations presented herein are implemented in design and constmction ofthe project. I li 6.1.2 The plaimed earthwork consists of cuts along the westem side and fills along the eastem side ofthe alignment south ofthe proposed bridge. North ofthe proposed bridge, cuts and fill are expected to be relatively minor. Existing alluvium beneath proposed bridge abutments will be removed and replaced with compacted fill to heights of up to about 30 P feet. All grading should be performed in conformance with Sections 6-3, 19-3, 19-5 and 19-6 of the Caltrans Standard Specifications. to iii 6.2 Grading 6.2.1 A preconstmction conference should be held at the site prior to the beginning of grading operations with the owner, contractor, civil engineer and soil engineer in attendance, to Special soil handling requirements can be discussed at that time. h Z to 6.2.2 Grading of the alignment should commence with the removal of all existing vegetation to aud existing improvements from the areas to be graded. Deleterious debris such as wood, asphalt and concrete should be exported from the site and should not be mixed with the fill soils. All existing underground improvements within the proposed improvement areas to should be removed and the resulting depressions properly backfilled in accordance with ^ the procedures described herein. tm 6.2.3 Existing undocumented fill and topsoil and alluvium within the proposed bridge abutment to areas should be removed to exposed granitic rock. Excavated soils generated from cut operations 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 approximately 8 inches to thick, moisture conditioned to a water content above optimum moisture content, and ^ compacted to at least 90 percent relative compaction, as determined by ASTM Test ^ Method D 1557-91. The upper 12 inches of fill beneath pavement should be moisture _ conditioned and compacted to 95 percent relative compaction. Project No. 06535-22-01 - 6 - July 17, 2000 6.2.4 Import fill soil should consist of granular materials with a "low" expansion potential (EI less than 50) free of deleterious material or stones larger than 3 inches and should be compacted as recommended above. The soils engineer should be notified ofthe import soil source and should perform laboratory testing of import soil prior to its arrival at the site to determine its suitability as fill material.. 6.2.5 Residential and commercial development is ongoing in the North County coastal area and to import soils are expected to be readily available. In addition, commercial sand and gravel I'i quarries are located in San Marcos and Oceanside. Excess materials can be readily c exported from the site due to the quality of the on-site soils. However, export of oversize |y rock may be more difficult. The contractor should design rock excavation methods to minimize oversize rock and avoid the need for second^ breakage. 6.3 Settlements 6.3.1 Surface settlement can be expected where substantial thicknesses of new fill will be placed. Based on the current plans, a maximum fill thickness is about 30 feet at the proposed bridge abutments. Settlements will occur as a result of compression of the new fill. The total settlement is directly related to the thickness of new fill. Total ground surface settlement at abutments is predicted to be about 1 inch. We anticipate that most of the settlement will occur as loads are applied. to to 6.4 Slopes 6.4.1 Temporary slopes may be excavated no steeper than 1:1 (horizontal to vertical) without few shoring provided the top of the excavation is a minimum of 15 feet from the edge of ^ existing buildings and other improvements. Excavations steeper than 1:1 or closer than 15 te feet from an existing improvement, should be shored in accordance with applicable OSHA codes and regulations. to 6.4.2 Permanent fill slopes should be no steeper than 2:1 (horizontahvertical). Permanent cut slopes in granitic rock can be excavated at 1 Vz\ 1 inclinations. The final cut and fill slopes have a calculated overall static factor of safety of 1.5. Under pseudo-static conditions, a factor of safety of 1.2 was calculated. Considering the relatively conservative strength assumptions used, the limitations inherent in the pseudo-static method of analysis, and experience with slopes constmcted using similar materials, the proposed slopes are expected to perform satisfactorily under both static and earthquake loading conditions. Project No. 06535-22-01 - 7 - July 17, 2000 6.4.3 Fill slopes will be composed of granular soils that are susceptible to surface erosion. Consideration should be given to the use of jute mesh of other surface treatment to minimize transport by runoff until adequate vegetation can take root. All roadway drainage should be directed to appropriate collection and discharge facilities so that run- off does not flow over the tops of slopes. 6.4.4 The current design shows V/i.l rip rapped slopes under the proposed bridge abutments. These slopes will be addressed in the Structure Foundation Report for the proposed bridge. 6.4.5 The City ofCarlsbad Supplemental Standard No. GS-14 dated April 20, 1993, Grading of Slopes and Required Setbacks, required one minimum 20-foot-wide bench at mid-height for cut slopes over 100 feet high. No bench is required for cut slopes less than 40 feet high. Cut slopes between 40 and 100 feet high apparently require drainage benches at 25-foot height intervals. From a geotechnical standpoint, benching typically is not necessary for the stability of cut slopes in the rocks anticipated along the Rancho Santa Fe Road realignment. However, benching will assist vegetation growth, reduce erosion and may enhance the final appearance of high slopes. As noted above, the potential presence of adversely-oriented bedding planes, fractures or joints may necessitate benches or other methods of reducing the overall slope inclination. 6.4.6 Fill slopes should not be steeper than 2:1 in accordance with current geotechnical practice. The City of Carlsbad standards apparently require drainage benches at 25-foot height intervals on fill slopes. Fill slopes over 100 feet high require one 20-foot-wide bench at mid-height, while slopes less than 30 feet high do not require a bench. For this project, drainage benches approximately as shown in the standards, or an equipment-width bench midway on slopes 100 feet high, if any, would be appropriate to minimize erosion and promote vegetation growth. 6.5 Earthwork Quantities 6.5.1 Shrinkage of about 5 to 10 percent should be anticipated for existing fill, topsoil and alluvium used as compacted fill. Granitic rock used in fill constmction is expected to increase in volume by about 10 to 25 percent. Rippable granitic rock would tend to bulk approximately 10 to 15 percent and non-rippable would likely bulk closer to the 15 to 25 percent value. Project No. 06535-22-01 - 8 - July 17, 2000 6.6 Excavation and Soil Characteristics 6.6.1 The majority of the soils in the upper 5 feet encountered in the field investigation are considered to have a "low" expansion potential (Expansion Index [EI] of 50 or less) as defined by the Uniform Building Code (UBC) Table No. 18-I-B. 6.6.2 All the in situ soils can be excavated with moderate to heavy effort by conventional heavy- duty equipment. The granitic rock is highly weathered; however, weathering decreases iH with depth. To access the ribbability of the granitic rock, air track borings, trenches and borings were drilled and seismic refraction surveys were performed. The most significant ^ cuts into rock will be at the westem side of the alignment between Station 255+00 and *• 260+00. Trenches T-80, T-81, T-101, T-102 and seismic refraction survey S-l indicate pa that the upper 5 feet of rock in this area is rippable. However, air track HT36 drilled to upslope of the cut area indicates that rippable material may extend deeper than the 5 feet indicated from other methods. Blasting will likely be required below this depth where ^ highly resistant rock is exposed. *" 6.6.3 It is the responsibility of the contractor to ensure that all excavations and trenches are properly shored and maintained in accordance with applicable OSHA mles and regulations «H in order to maintain safety and maintain the stability of adjacent existing improvements, to 6.7 Retaining Walls lw 6.7.1 Unrestrained walls are those that are allowed to rotate more than O.OOIH (where H equals ^ the height ofthe retaining wall portion of the wall) at the top of the wall. Retaining walls to not restrained at the top and having a level backfill surface should be designed for an ^ active soil pressure equivalent to the pressure exerted by a fluid density of 35 pcf. Where lg the backfill will be inclined at 2:1 (horizontahvertical), an active soil pressure of 52 pcf is recommended. 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. Soil placed for retaining wall backfill should meet the requirements outlined in m Section 6.1.2. M _ 6.7.2 All retaining walls should be provided with a drainage system adequate to prevent the - ^ buildup of hydrostatic forces. The drainage system should consist of weepholes or backdrains. The above recommendations assume a properly compacted granular (EI less ^ than 50) free-draining backfill material with no hydrostatic forces or imposed surcharge load. r L Project No. 06535-22-01 - 9 - July 17, 2000 E C 6.7.3 Retaining walls, if any, can be supported on granitic rock or properly compacted fill. The allowable bearing for walls founded on spread footings founded on granitic rock or properly compacted fill can be taken as 10,000 psf and 3,000 psf, respectively. These values can be increased by one-third when considering wind or earthquake loads. Footings should be a minimum of 3 feet in width. The horizontal distance from the surface of a slope to the bottom outside edge of the footing should be at least 7 feet. to L r te to i to 6.8 Preliminary Pavement Recommendations 6.8.1 The following recommendations are provided for preliminary design purposes. The final pavement section design will depend upon soil conditions exposed at subgrade elevation and the results of Resistance Value (R-Value) tests of the subgrade soils. The final •pavement sections may be significantly different from the preliminary sections. Two laboratory R-value tests was performed and the results indicate that existing subgrade soils have an R-value of approximately 54 to 68. Preliminary recommendations are provided below for flexible (asphalt concrete) pavement assuming that soils with an R-value of at least 40 are exposed at subgrade elevation. te to TABLE 6.8 FLEXIBLE PAVEMENT SECTION Assumed Traflic Index Assumed Subgrade R-Value Asphalt Concrete (inches) Class 2 ./ggregate Base (inches) 5.0 40 3 3'/2 6.0 40 3 6 7.0 40 VA 8 8.0 40 4/2 8'/2 9.0 40 5 lO'/s 10.0 40 6 11 11.0 40 6'/2 13 12.0 40 7'/2 14 6.8.2 Subgrade soil should be compacted to a minimum of 95 percent relative compaction to a depth of 12 inches beneath pavements. ProjectNo. 06535-22-01 - 10-Juty 17, 2000 6.8.3 Class 2 base should conform to Section 26-1.028 of the Standard Specifications for TTie State of Califomia Department ofTransportation (Caltrans) with a %-inch maximum size aggregate and should be compacted to a minimum of 95 percent of the maximum dry density at near optimum moisture content. The asphalt concrete should conform to Section 203-6 of the Standard Specifications for Public Works Construction (Green Book). 6.8.4 The performance of asphalt concrete pavements is highly dependent upon providing positive surface drainage away from the edge of the pavement. Ponding of water on or adjacent to the pavement will likely result in pavement distress and subgrade failure. 6.9 Corrosion 6.9.1 The soils on-site are only mildly to moderately corrosive with respect to concrete and steel. This site does not have to be considered a corrosive environment, based on Caltrans criteria. Type II Portland cement should be used in concrete in contact with the ground. Adequate concrete cover over reinforcing steel should be provided in accordance with good constmction practices and design standards.. 6.10 Culverts 6.10.1 Culverts will be founded in properly compacted fill or granitic rock. The final location and sizes of culverts is unknown at this time. No special foundation considerations are necessary. If culverts will be located in cut areas where difficult excavation may occur, consideration should be given to undercutting the culvert area during mass grading operations. Corrosion recommendations are presented in Section 6.9. I ; 6.11 Geotechnical and Construction Review 6.11.1 Geocon Incorporated should review the grading plans and foundation plans prior to final 1^ design submittal to determine if additional analysis and/or recommendations are required. te Project No. 06535-22-01 - 11 - July 17, 2000 E E LIMITATIONS AND UNIFORMITY OF CONDITiONS 1. The recommendations ofthis 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 constmction, or if the proposed constmction will differ from that anticipated 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. 2. This report is issued with the understanding that it is the responsibility of the owner or his p, representative to ensure that the information and recommendations contained herein are |g brought to the attention ofthe 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. P 3. 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 ofthis 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. c to te to ProjectNo. 06535-22-01 July 17,2000 SOURCE : 2000 THOMAS BROTHERS MAP LOS ANGELES COUNTY. CALIFORNtA REPRODUCED WITH PERMISSION GRANTED BY THOPJUS BROTHERS MAPS, THIS UAP IS COPYRIGHTED BY THOMAS BROS. MAPS. IT IS UNLAWFUL TO COPY OR REPRODUCE ALL OR ANY PART THEREOF, WHET>1ER FOR PERSONAL USE OR RESALE, WnWUT PERMISSION GEOCON CONSULTANTS. INC. ENVIRONMENTAL • GEOTECHNICAL • MATERIALS 6970 FLINDERS DRIVE - SAN DIEGO, CAUFORNIA 92121 - 2974 PHONE 858 558-6100 • FAX 858 558-8437 JV/JMW DSK/EOOOO VICINITY /v\AP RANCHO SANTA FE ROAD REALIGNMENT CARLSBAD, CALIFORNIA DATE PROJECT NO. 06535 - 22 - 01 FIG. 1 X/R1*1DRAFTlNG/JIMW/716/raantfe2 to APPENDIX A FIELD INVESTIGATION The field investigation was performed on June 21 through 23, 2000, and consisted of the excavation of four small diameter borings and 17 bacldioe trenches at the approximate locations shown on Logs of Test Borings (Figures 1 through 12). The small-diameter borings were drilled to depths ranging from 7'/2 feet to 23 feet below existing grade using a Ingersoll-Rand ASOO tmck-mounted drill rig equipped with 8-inch-diameter, hollow-stem auger. Relatively undisturbed samples were obtained with the drill rig by driving a 3-inch O. D., ^split-tube sampler 12 inches into the undisturbed soil mass with blows from a 140-pound hammer falling 30 inches. The split-tube sampler was equipped with 1-inch-high by 2V8-inch-diameter, brass sampler rings to facilitate sample removal and testing, fp Standard penetration tests (SPT) were performed by driving a 2-inch O.D. split spoon sampler 18 ki inches in accordance with ASTM D 1586. The number of blows to drive the sampler the last 12 of 18 inches is reported. Disturbed bulk samples were obtained from drill cuttings and SPT testing. [ The trenches were excavated with John Deere 555 track hoe with a 24-inch wide bucket. In addition to the borings and trenches for the current investigation, six air track borings, eight small diameter borings and two trenches from the previous geotechnical investigation excavated in the general to vicinity of the bridge are included on the Log of Test Boring sheets. Results of seismic refraction surveys are presented in Appendix D. ^ The soil conditions encountered in the trenches were visually examined, classified, and logged in general conformance with the American Society for Testing and Materials (ASTM) Practice for Description and Identification of Soils (Visual - Manual Procedure D2844). The logs of the borings to and trenches excavated for the current investigation are presented on Figures A-l through A-21. The I" logs depict the various soil/rock types encountered and indicate the depths at which samples were li obtained. L ProjectNo. 06535-22-01 July 17, 2000 PROJECT NO. 06535-22-OlA DEPTH IH FEET SAHPLE HO. > CD O _l o X t-H SOIL CLASS (USCS) BORING B 101 ELEV. (MSL.) 333 EQUIPMENT DATE COMPLETED IR300A 6/23/00 ;UJ' (J, H n Ku a u - 0 MATERIAL DESCRIPTION 2 - - 4 - - 6 - - 8 - - 10 - Bl-1 Bl-2 Bl-3 Bl-4 Bl-5 - 12 5M/ML FILL Dense, dry, moderate yellowish-brown, fine to medium, Silty SAND/Sandy SILT -Encountered concrete chunk at 5 feet, pulled rig forward 3 feet 44 127.7 3.4 ML ALLUVIUM Soft, wet, moderate brown, Sandy SILT -No recovery 52 BORING TERMINATED AT 12 FEET (REFUSAL) Figure A-l, Log of Boring B 101 RSFRB SAMPLE SYMBOLS • ... SAMPLING UNSUCCESSFUL B ... STANDARD PENETRATION TEST • ... DRIVE SAMPLE (UNDISTURBED) ^ ... DISTURBED OR BAG SAMPLE B ... CHUNK SAMPLE Z ... UATER 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 TG BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAHPLE NO. o SOIL CLASS (USCS) BORING B 102 ELEV. (MSL.) 327 EQUIPMENT DATE COMPLETED IR300A 6/23/00 Pit UJ z a. (J o - 0 MATERL\L DESCRIPTION - 2 - - 4 - - 6 - B2-1 B2-2 B2-3 ite te to h to te ALLUVIUM Firm to soft, damp, grayish-brown, Sandy SILT, highly organic and odorous 4L/MH -No recoveiy Refiisal, pull rig forward 5 feet, refiisal at same depth BORING TERMINATED AT 7.5 FEET (REFUSAL) 18 25/5' 118.9 17.3 to to Figure A-2, Log of Boring B 102 RSFRB to ^A.^T^T r< r.w«,n^i r. D... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS ^ ... DISTURBED OR BAG SAMPLE E. &. . STANDARD PENETRATION . CHUNK SAMPLE TEST 1 ... DRIVE Z ... WATER SAMPLE (UNDISTURBED) TABLE OR SEEPAGE mm 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAHPLE NO. >• (S O _l o X I-H SOIL CLASS (USCS) BORING B 103 ELEV. (MSL.) 335 EQUIPMENT DATE COMPLETED R300A 6/23/00 (0 > s-g. Ul a Ql O to UJ •o CJ - 0 MATERIAL DESCRIPTION - 2 - - 4 - 6 - 8 - h 10 - B3-1 B3-2 B3-3 B3-4 I 5M/ML ALLUVIUM Loose, moist, moderate brown, fine to coarse, Silty SAND/Sandy SILT -Moist to wet -No recovery ML Firm, moist to wet, dark yellowish-brown, Sandy SILT BORING TERMINATED AT 11 FEET (REFUSAL) 23 PUSH 3 85.1 5.7 11 114.0 17.4 Figure A-3, Log of Boring B 103 RSFRB 1 to SAMPLE SYMBOLS ° *'' '"^''''^ UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. . STANDARD PENETRATION TEST 1... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE I ... 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. PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE NO. > CD O _I o X 1-H SOIL CLASS (USCS) BORING B 104 ELEV. (MSL.) 328 EQUIPMENT DATE COMPLETED IR300A 6/23/00 ;UJ- UjcoP UJ Q.' in go a ob u - 0 - 2 - 4 H 6 8 - 10 - - 12 - - 14 - - 16 - - 18 - - 20 - - 22 - MATERIAL DESCRIPTION B4-1 B4-2 B4-3 B4-4 SW [ CH I [ A A\ -A'}- •b .i-j-i- ALLUVIUM Loose, dry, moderate brown, fine to coarse SAND, some silt -Black silt, soft, moist -Seepage below 4 feet 15 109.5 20.6 Stiff, wet, mottled oranges and olives, Sandy CLAY ESCONDIDO CREEK GRANODIORITE Highly weathered, mottled dark yellowish-orange, weak to moderately strong. Excavates as Silty, fine to coarse SAND with angular cobbles 75 124.0 90 -Becomes highly to moderately weathered 12.3 BORING TERMINATED AT 23 FEET (REFUSAL) Figure A-4, Log of Boring B 104 RSFRB SAMPLE SYMBOLS • ... SAMPLING UNSUCCESSFUL E. . STANDARD PENETRATION TEST • . . DRIVE SAMPLE (UNDISTURBED) SAMPLE SYMBOLS ^ ... 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAMPLE NO. > CD O _I o X t-H SOIL CLASS (USCS) TRENCH T 101 ELEV. (MSL.) 420 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE :co! Hi UJ UJ a g^ u - 0 MATERLU. DESCRIPTION Tl-1 - 2 - - 4 - !to te w te to te SM TOPSOIL Loose to medium dense, dry, moderate brown, Silty, fine to coarse SAND, highly porous, abundant roots ESCONDIDO CREEK GRANODIORITE Highly to conpletely weathered, joints £9proximately 6" spacing, random orientations, weak, dry, mottled reds and browns; excavates as a Silty SAND with gravel and cobble sized angular clasts -Becomes moderately weathered at 4 feet TRENCH TERMINATED AT 5 FEET (REFUSAL) Figure A-5, Log of Trencli T 101 RSFRB to o » . ,T,«T ^ n ... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS _ ^ ... DISTURBED OR BAG SAMPLE D ... STANDARD PENETRATION TEST E ... CHUNK SAMPLE 1... DRIVE SAMPLE (UNDISTURBED) Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWH 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAMPLE NO. >-CD O _l o X I-H SOIL CLASS (USCS) TRENCH T 102 ELEV. (MSL.) 424 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE UJ Uls; gu^ UJ^5 g^ *-o u - 0 MATERIAL DESCRIPTION 2 - - 4 - to SM - -rf I TOPSOIL Loose to inedium dense, dry, moderate brown, Sil^, fine to coarse SAND, highly porous, abundant roots ESCONDIDO CREEK GRANODIORITE Highly to conq)letely weathered, joints approximately 6" spacing random orientations, weak, dry, mottled reds and browns, excavates as a Silty SAND with gravel and cobble sized angular clasts -Becomes moderately weathered at 4 feet TRENCH TERMINATED AT 5 FEET (REFUSAL) Figure A-6, Log of Trench T 102 RSFRB o » . ,«T r. r^.r. ,r.«T ^ L] ... SAMPL I NG UNSUCCESSFUL SAMPLE SYMBOLS _ ^ ... DISTURBED OR BAG SAMPLE E ... STANDARD PENETRATION B ... CHUNK SAMPLE TEST 1 . ¥ • . DRIVE . WATER SAMPLE (UNDISTURBED) TABLE OR SEEPAGE NOTE: TKE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES OHLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESEHTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE NO. CD O SOIL CLASS (USCS) TRENCH T 103 ELEV. (MSL.) 382 EQUIPMENT _DATE COMPLETED JD 555 TRACK HOE 6/21/00 Hyi- HSU. UJrnO zHjj UJ^CD gu: UJ •o u - 0 MATERIAL DESCRIPTION T3-1 - 2 - - 4 - to te SM •'•| 9 TOPSOIL Loose to medium dense, dry, moderate brown, SUty, fine to coarse SAND, highly porous, abimdant roots ESCONDIDO CREEK GRANODIORITE Highly to completely weadiered, joints approximately 6" spacing, random, mottled reds and browns, weak; excavates as a Silty SAND with gravel and cobble sized angular clasts -At 3 feet becomes moderately weathered, moderately strong TRENCH TERMINATED AT 5 FEET (REFUSAL) Figure A-7, Log of Trench T 103 RSFRB SAMPLESYMBOLS ° UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST 1... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE I ... UATER 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAHPLE NO. > CD O SOtL CLASS (USCS) TRENCH T104 ELEV. (MSL.) 382 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE ori • UJrnO >9; a H UJ •o u - 0 - 2 MATERL\L DESCRIPTION 3 to in m SM .1- TOPSOIL Loose to medium dense, dry, moderate brown, Sil^, fine to coarse SAND, highly porous, abundant roots ESCONDIDO CREEK GRANODIORITE Highly to coiiq)letely weathered, joints proximately 6" spacing, random, mottled reds and browns, weak, excavates as a Silty SAND with gravel and cobble sized angular clasts -At 2 feet becomes moderately weathered, moderately strong TRENCH TERMINATED AT 2 FEET (REFUSAL) Figure A-8, Log of Trench T 104 RSFRB SAMPLESYMBOLS ° UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST H... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE I ... 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAHPLE NO. H SOIL CLASS (USCS) TRENCH T105 ELEV. (MSL.) 328 EQUIPMENT DATE COMPLETED 6/21/00 JD555 TRACKHOE Ui' ^(O £uj a. H' (0, a UJ6* g^ ^o u - 0 MATERIAL DESCRIPTION T5-1 li to 11 m to te - 2 - - 4 - - 6 - - 8 - - 10 - - 12 - T5-2 ML ALLUVIUM Soft, damp, dark brown, Sandy SILT, abundant roots ML I. Becomes wet below 3 feet, with seepage, abundant angular cobbles and boulders to 2 feet diameter, olive black, organic odors -Heavy seepage, standing water ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fine to coarse SAND with angular cobbles TRENCH TERMINATED AT 13 FEET Figure A-9, Log of Trench T 105 RSFRB SAMPLESYMBOLS ° - UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST 1... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATtON AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE HO. >• CD O _J O X I- H SOIL CLASS (USCS) TRENCH T 106 ELEV. (MSL.) 326 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE jUJ' u, :<o Q. gci gz O - 0 MATERIAL DESCRIPTION - 2 - - 4 - 6 - 8 ML AliUVIUM Soft, damp, dark brown, Sandy SILT, abundant roots ML Becomes wet below 3 feet, with seq)age, abundant angular cobbles and boulders to 2 feet diameter, olive black, organic odors -Heavy seepage, standing water ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fine to coarse SAND with angular cobbles TRENCH TERMINATED AT 8 FEET Figure A-10, Log of Trench T 106 RSFRB SAMPLE SYMBOLS • SAMPLING UNSUCCESSFUL E... STANDARD PENETRATION TEST I... DRIVE SAMPLE (UNDISTURBED) ^ ... DISTURBED OR BAG SAMPLE B ... CHUNK SAMPLE Z ... UATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT TKE 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAMPLE NO. > CD O _] O X SOIL CLASS (USCS) TRENCH T 107 ELEV. (MSL.) 328 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE H ;Ui' UJ ag a gz u - 0 MATERIAL DESCRIPTION - 2 - - 4 - T7-1 ^L/SM vlL/SM ALLUVIUM Soft, danq), dark brown, Sandy SILT/Silty SAND, abundant roots Below 2 feet becomes wet, olive black, organic odor, with seepage, standing at 4 feet VlL/SM Below 4 feet abundant cobbles and boulders to 2 feet diameter -.4 ii \ ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fme to coarse SAND with angular cobbles TRENCH TERMINATED AT 8 FEET Figure A-l: L, Log of Trench T 107 RSFRB to SAMPLESYMBOLS ° - '''''''' UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPIE E. B. . STANDARD PENETRATION TEST B... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT TKE 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. to PROJECT NO. 06535-22-OlA DEPTH IN FEET SAHPLE NO. > CD O _1 o X t-H SOIL CLASS (USCS) TRENCH T108 ELEV. (MSL.) 335 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE ftUJ'^ Ofi • Hyi- uiHo Zm-I H' to, go a UJ6' g^ ^o u m> - 0 MATERIAL DESCRIPTION - 2 - - 4 - - 6 - - 8 - - 10 T8-1 T8-2 - 12 ALLUVIUM Loose, moist, moderate brown, fme to coarse, Silty SAND/Sandy SILT 5M/ML 104.9 6.9 3M/ML Heavy seepage, standing water and caving between 9 and 11 feet ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fme to coarse SAND with angular cobbles TRENCH TERMINATED AT 12 FEET Figure A-12, Log of Trench T 108 RSFRB D SAMPLING UNSUCCESSFUL SAMPLESYMBOLS ^ SMni-Lirib UH:>ULLi:«ruL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATION TEST 1... DRIVE SAMPLE (UNDISTURBED) . CHUNK SAMPLE Z ... 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. to PROJECT NO. 06535-22-OlA DEPTH IN FEET SAMPLE NO. > CD O _l O X I- H SOIL CLASS (USCS) TRENCH T 109 ELEV. (MSL.) 326 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE <ES\ a' O s| gz ^o u - 0 MATERLAL DESCRIPTION - 2 - - 4 - - 6 - to to ML ML ALLUVIUM Soft, dry, dark brown, Sandy SILT Becomes saturated, heavy seepage, standing water, approximately 50% cobbles and boulders (angular and rounded) up to 18 inches diameter, caving, cannot keep trench open ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fine to coarse SAND with angular cobbles TRENCH TERMINATED AT 7 FEET Figure A-13, Log of Trench T 109 RSFRB SAMPLE SYMBOLS • ... SAMPLING UNSUCCESSFUL E ... STANDARD PENETRATION TEST • ... DRIVE SAMPLE (UNDISTURBED) ^ ... DISTURBED OR BAG SAMPLE B ... CHUNK SAMPLE Z ... 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. PROJECT NO. 06535-22-OlA DEPTH IN FEET SAMPLE NO. > CO o _I o X H SOIL CLASS (USCS) TRENCH TllO ELEV. (MSL.) 327 EQUIPMENT DATE COMPLETED 6/21/00 JD 555 TRACK HOE OS Q. Sul en a uj^5 - 0 MATERIAL DESCRIPTION - 2 - - 4 - - 6 - - 8 to ML ALLUVIUM Soft, dry, dark brown, Sandy SILT ML Becomes saturated, heavy seepage, ^)proximately 50% cobbles and boulders, (an^ar and rounded) up to 18 inches diameter, caving, cannot keep trench open ESCONDIDO CREEK GRANODIORITE Highly weathered, weak to moderately strong, mottled browns and oranges, excavates as Silty, fme to coarse SAND with angular cobbles TRENCH TERMINATED AT 8 FEET Figure A-14, Log of Trench T 110 RSFRB SAMPLE SYMBOLS ° - UNSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. .. STANDARD PENETRATION TEST 1 ... DRIVE SAMPLE (UNDISTURBED) .. CHUNK SAMPLE Z ... UATER TABLE OR SEEPAGE to NOTE: THE LOG Of SUBSURFACE CONDITIOHS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS HOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. to te PROJECT NO. 06535-22-OlA DEPTH IH FEET SAHPLE NO. > CD O -J o X h-H SOtL CLASS (USCS) TRENCH T 111 ELEV. (MSL.) 332 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE ;UJ' U. ^(oo gci >S; a g^ U - 0 MATERIAL DESCRIPTION I - 2 - - 4 - - 6 - 8 - - 10 - - 12 - - 14 -rr •\ -41 ALLUVIUM Loose to medium dense, damp, moderate brown to dark brown, Silty, fine to coarse SAND, scattered cobbles and boulders up to 2 feet diameter SM -Steel storm drain SM Seepage, standing water at 10 feet Becomes saturated ESCONDIDO CREEK GRANODIORITE Moderately to highly weathered, weak to moderately weak, mottled browns and oranges, excavates as Silty, fme to coarse SAND TRENCH TERMINATED AT 14 FEET Figure A-15, Log of Trench T 111 RSFRB ^ . . r- r,,« r, D ... SAMPLING UNSUCCESSFUL SAMPLE SYMBOLS ^ ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PEHETRATIOH TEST 1... DRIVE SAMPLE (UHOISTURBED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE HOTE: THE LOG OF SUBSURFACE COHDITIOHS SHOWN HEREOH APPLIES OHLY AT THE SPECIFIC BORING OR TRENCH LOCATION AHO AT THE DATE INDICATED. IT IS HOT WARRANTED TO BE REPRESEHTATIVE OF SUBSURFACE COHDITIONS AT OTHER LOCATIONS AND TIMES. te PROJECTNO. 06535-22-OlA DEPTH IN FEET SAMPLE HO. CD O H SOIL CUSS (USCS) TRENCH T 112 ELEV. (MSL.) 333 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE H ;UJ' CJ. UJ gci a LJ$> or Hi !Z •o L) to to to m te - 0 MATERIAL DESCRIPTION T12-1 - 2 - - 4 - 6 - 8 - - 10 - - 12 - - 14 - - 16 te m te SM ALLUVIUM Loose to inedium dense, damp, moderate brown to dark brown, Silty, fine to coarse SAND, approximately 20% boulders up to 2 feet diameter Becomes damp, increase in boulders, prevelant caving SM \ ESCONDIDO CREEK GRANODIORITE Moderately to highly weathered, weak to moderately weak, mottled browns and oranges, excavates as Silty, fine to coarse SAND / TRENCH TERMINATED AT 16 FEET Figure A-16, Log of Trench T 112 RSFRB SAMPLESYMBOLS ° - UHSUCCESSFUL ^ ... DISTURBED OR BAG SAMPLE E. B. .. STANDARD PENETRATION TEST • ... DRIVE SAMPLE (UNDISTURBED) .. CHUNK SAMPLE Z ... UATER TABLE OR SEEPAGE HOTE: THE LOG OF SUBSURFACE COHDITIOHS SHOWN HEREON APPLIES OHLY AT TKE SPECIFIC BORIHG OR TREHCH LOCATIOH AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIOHS AT OTHER LOCATlOHS AHD TIMES. te PROJECTNO. 06535-22-OlA to te to ito to te to to DEPTH IN FEET SAMPLE HO. >-CD O _l O X SOIL CLASS (USCS) TRENCH T113 ELEV. (MSL.) 335 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE On • UJ ^9 >- fi- UJ o >-b tr a % g^ u - 0 MATERL\L DESCRIPTION - 2 - - 4 - - 6 - TOPSOIL Soft, dry, moderate brown, Sandy SILT ALLUVIUM L(X)se to medium dense, moist, moderate and reddish-brown. Clayey SAND / 136.1 15.2 ESCONDIDO CREEK GRANODIORITE Moderately to highly weathered, mottled browns and oranges, weak to moderately weak, excavates as Silty, fine to coarse SAND TRENCH TERMINATED AT 7 FEET Figure A-17, Log of Trench T 113 RSFRB SAMPLE SYMBOLS • ... SAMPLING UNSUCCESSFUL E ... STANDARD PENETRATION TEST I ... DRIVE SAMPLE (UNDISTURBED) ^ ... DISTURBED OR BAG SAMPLE B ... CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATIOH AND AT THE DATE IHDICATED. IT IS NOT WARRAHTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. to PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE HO. >• CD O _l O SOIL CLASS (USCS) TRENCH T 114 ELEV. (MSL.) 340 EQUIPMENT __DATE COMPLETED JD 555 TRACK HOE 6/22/00 UJ *o5 UJs gci UJ6* Sg gz EQ U ^ - 0 MATERIAL DESCRIPTION 4 - 2 - - 4 - - 6 - SM TOPSOIL Loose to medium dense, dry, moderate brown, Silty, fine to coarse SAND, highly porous, abundant roots ESCONDIDO CREEK GRANODIORITE Moderately to slightly weathered, closely spaced joints, mottled, strong to moderately strong, Becomes strong to very strong TRENCH TERMINATED AT 7 FEET (REFUSAL) c to b Figure A-18, Log of Trench T 114 RSFRB to SAMPLE SYMBOLS • ... SAMPLIHG UNSUCCESSFUL E. . STAHDARD PENETRATIOH TEST • . . DRIVE SAMPLE (UNDISTURBED) SAMPLE SYMBOLS B. SAMPLE (UNDISTURBED) ^ ... DISTURBED OR BAG SAHPLE B. . CHUHK SAMPLE z. . WATER TABLE OR SEEPAGE ^ NOTE: THE LOG OF SUBSURFACE COHDITIOHS SHOWH HEREOH APPLIES OHLY AT TKE SPECIFIC BORIHG OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS HOT WARRAHTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIOHS AT OTHER LOCATIONS AHD TIMES. te PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE HO. > CD O -I O X I- H SOIL CUSS (USCS) TRENCH T115 ELEV. (MSL.) 345 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE CO' UJ^ Ss gu. go tr a UJ^ UJ - 0 MATERL\L DESCRIPTION - 2 - - 4 - - 6 - 8 10 T15-1 T15-2 T15-3 T15-4 T15-5 to I 4-. 1 ML \ TOPSOIL Soft to firm, dry, dark yellowish-brown, Sandy SILT SM ALLUVIUM Loose, damp, moderate yellowish-brown, Silty, fine to medium SAND, highly porous 112.2 15.7 Becomes olive black, mottled yellowish-orange, wet to saturated 99.9 15.7 \ ESCONDIDO CREEK GRANODIORITE Highly weathered, mottled yellow, browns, greens, grays and blues, weak, excavates as Silty SAND with coarse gravel TRENCH TERMINATED AT 11 FEET Figure A-19, Log of Trench T 115 RSFRB SAMPLE SYMBOLS • SAMPLING UNSUCCESSFUL E. . STANDARD PENETRATION TEST 1. . DRIVE SAMPLE (UHOISTURBED) SAMPLE SYMBOLS B. SAMPLE (UHOISTURBED) ^ ... DISTURBED OR BAG SAMPLE B. . CHUNK SAMPLE ^ • . WATER TABLE tiR SEEPAGE NOTE: THE LOG OF SUBSURFACE CONDITIOHS SHOWH HEREON APPLIES OHLY AT THE SPECIFIC BORIHG OR TRENCH LOCATION AHD AT TKE DATE IHDICATED. IT IS HOT WARRAHTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIOHS AT OTHER LOCATIONS AHD TIMES. r to PROJECT NO. 06535-22-OlA L C te DEPTH IN FEET SAMPLE HO. > CD O -I O X t- SOIL CUSS (USCS) TRENCH T 116 ELEV. (MSL.) 372 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE H CJ, (O <c (0,.* a •o u - 0 MATEIUAL DESCRIPTION - 2 - T16-1 T16-2 to to ML TOPSOIL Firm to stiff, dry, light brown, Sandy SILT, rootlets, highly porous ESCONDIDO CREEK GRANODIORITE Moderately weathered, mottled, strong, excavates as 6" to 2' diameter angular clasts TRENCH TERMINATED AT 3 FEET (REFUSAL) y Figure A-20 , Log of Trench T 116 RSFRB SAMPLE SYMBOLS • SAMPLING UNSUCCESSFUL E. . STAHDARD PENETRATIOH TEST . DRIVE SAMPLE (UHOISTURBED) ^ ... DISTURBED OR BAG SAMPLE B. . CHUHK SAMPLE ¥ • . WATER TABLE OR SEEPAGE NOTE: TKE LOG OF SUBSURFACE CONDITIOHS SHOWH HEREON APPLIES OHLY 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. to PROJECT NO. 06535-22-OlA DEPTH IH FEET SAMPLE NO. CD O i-H SOIL CUSS (USCS) TRENCH T 117 ELEV. (MSL.) 355 EQUIPMENT DATE COMPLETED 6/22/00 JD 555 TRACK HOE :co (0 ^co° •KS >w UJ^ Pi- co UJ - 0 MATEIUAL DESCRIPTION - 2 - - 4 - - 6 - - 8 - T17-1 T17-2 - 10 to SM FILL Loose to medium dense, damp, dark yellowish-brown, Silty, fine to coarse SAND ALLUVIUM Soft, damp, light and moderate brown, Sandy SILT, higjily porous ML 104.2 12.6 ESCONDIDO CREEK GRANODIORITE Slightly to moderately weathered, very strong TRENCH TERMINATED AT 10 FEET Figure A-2] , Log of Trench T 117 RSFRB to D ... SAMPLING UNSUCCESSFUL SAMPLESYMBOLS ^ ^.^n^-LiNb un SULLEN PUL ^ ... DISTURBED OR BAG SAMPLE E. B. . STANDARD PENETRATIOH TEST 1... DRIVE SAMPLE (UHDISTUR8ED) . CHUNK SAMPLE Z ... WATER TABLE OR SEEPAGE ^ NOTE: TKE LOG OF SUBSURFACE COHDITIONS SHOWH HEREOH APPLIES OHLY AT THE SPECIFIC BORING OR TRENCH LOCATIOH AND AT TKE OATE INDICATED. IT IS NOT WARRANTED TO BE REPRESEHTATIVE OF SUBSURFACE COHDITIONS AT OTHER LOCATIONS AND TIMES. to m APPENDIX B LABORATORY TESTING Laboratory tests were performed in accordance with generally accepted test methods of the American Society for Testing and Materials (ASTM) or other suggested procedures. Selected soil samples were tested for their shear strength characteristics and grain size distribution. Selected soils samples were also tested for pH, resistivity, chloride ion content and sulfate content. The results of our laboratory tests are presenfed on Tables B-I through B-V and Figures B-1 through B-3. The results of chloride ion content tests performed by Clarkson Laboratory and Supply Incorporated also are presented herein. TABLE B-I SUMMARY OF DIRECT SHEAR TEST RESULTS Sample No. Dry Density (pcf) Moisture Content (%) Unit Cohesion (psf) Angle of Shear Resistance (degrees) B104-3 124.0 12.3 900 42 T105-1* 87.4 20.1 0 38 •Sample remolded to approximately 90 percent of maximum dry density at near optimum moisture content. TABLE B-II SUMMARY OF LABORATORY IMAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT TEST RESULTS Sample No. Description Maximum Dry Density (pcf) Opttmum Moisture Content (% dry wt.) TlOl-1 Silty SAND 130.5 9.4 T105-1 Black Sandy SILT with organics 98.2 19.1 Project No. 06535-22-01 -B-1 -July 17, 2000 te to k TABLE B-lll SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS (ASTM 4829) Sample No. Moisture Content Dry Density (pcf) Expansion Index Sample No. Before Test (%) After Test (%) Dry Density (pcf) Expansion Index T103-1 7.2 19.5 121.8 0 T113-2 8.2 23.4 117.1 43 to TABLE B-IV SUMMARY OF LABORATORY RESISTANCE VALUE TEST RESULTS (CALiFORNIA TEST METHOD NO. 301) Sample No. Description R-Value T115-2 Yellow brown Silty SAND 68 T117-2 Brown, Silty SAND to Sandy SILT 54 TABLE B-V SUMMARY OF LABORATORY WATER SOLUBLE SULFATE TEST RESULTS Sample V/ater Soluble Sulfate No. (%) p» T112-1 0.006 to T116-2 0.006 ProjectNo. 06535-22-01 -B-2-July 17, 2000 TABLE B-VI SUMMARY OF LABORATORY CHLORIDE ION CONTENT TEST RESULTS to ii Sample No. Chloride Ion Content (ppm) T112-1 33 T116-2 25 to te k TABLE B-VII SUMMARY OF LABORATORY pH and RESISTIVITY TEST RESULTS Sample No. pH Minimum Resistivity (ohm-centimeters) T112-1 7.2 2201 T116-2 6.9 4755 Project No. 06535-22-01 -B-3-July 17, 2000 to PROJECTNO. 06535-22-01 GRAVEL SAND SILT OR CLAY COARSE FINE :OARSE MEOIUn FINE SILT OR CLAY U. S. STANDARD SIEVE SIZE 1 0.1 GRAIN SIZE IN MILLIMETERS 0.001 SAMPLE Depth (ft) CLASSIFICATION VAT WC LL PL PI • TlOl-1 1.0 (SM) to IZl T107-1 3.0 (SM) GRADATION CURVE RANCHO SANTA FE BRIDGE CARLSBAD, CALIFORNIA RSFBl Figure B-1 PROJECTNO. 06535-22-01 o H <c o o if) o u Ul u tr Ul Q. SAMPLE NO. B2-1 -4 -2 10 12 0.1 10 APPLIED PRESSURE (ksf) Initial Dry Density (pcf) Initial Water Content (%) 100 Initial Saturation (%) 100 Sample Samrated at (ksf) 0.5 CONSOLroATION CURVE RSFB1 RANCHO SANTA FE BRIDGE CARLSBAD, CALIFORNU Figure B-2 PROJECTNO. 06535-22-01 o H O o (O o u UJ u tr us CL SAMPLE NO. T117-1 -4 -2 10 12 0.1 10 APPLIED PRESSURE (ksf) Initial Dry Density (pcf) Initial Water Content (%) 100 Initial Saturation (%) 56.4 Sample Saturated at (ksf) 0.5 CONSOLIDATION CURVE RANCHO SANTA FE BRIDGE CARLSBAD, CALIFORNIA RSFB1 Figure B-3 to te ^ APPENDIX C RECOMMENDED GRADING SPECIFICATIONS for RANCHO SANTA FE ROAD REALIGNMENT ^ STATION 252+00 TO MELROSE DRIVE CARLSBAD, CALIFORNIA to * PROJECT NO. 06535-22-01 to k [ to RECOMMENDED GRADING SPECIFICATIONS L 1. GENERAL p 1.1. These Recommended Grading Specilkations shall be used in conjunction with the ^ Geotechnical Report for the project prepared by Geocon Incorporated. The recom- mendations contained in the text of the Geotechnical Report are a part ofthe earthwork and ^ grading specifications and shall supersede the provisions contained hereinafter in the case *• of conflict. ^ 1.2. Prior to the commencement of gradmg, 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. It will be necessary tfiat the Consultant provide adequate testing and observation services so that he may determine that, in his 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 him apprised of work schedules and changes so that personnel may be scheduled accordingly. to ^ 1.3. It shall be the sole responsibility of the Contractor to provide adequate equipment and to 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, and so forth, result in a quality of work ^ not in conformance with these specifications, the Consultant will be empowered to reject to the work and recommend to the Owner that construction be stopped until the unacceptable 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 perfonned and who has contracted with the Contractor to have grading performed. ^ 2.2. Contractor shall refer to the Contractor performing the site grading work, te 2.3. Civil Engineer or Engineer of Work shall refer to the Califomia licensed Civil Engineer or consuhing firm responsible for preparation of the grading plans, surveying and verifying as-graded topography. GI rev. 8/98 to to 2.4. Consultant shall refer to the soil engineering and engineering geology consulting firm retained to provide geotechnical services for thc project. 2.5. Soil Engineer shall refer to a Califomia 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 confonnance with these specifications. 2.6. Engineering Geologist siiatl 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 defmed 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. to te 3.1.2. Soii-rock fills are defined as fills containing no rocks or hard lumps larger than 4 p feet in maximum dimension and containing a sufficient matrix of soil fill to allow ll for proper compaction of soil fill around the rock fi'agments or hard lumps as specified in Paragraph 6.2. Oversize rock is defined as material greater than 12 ** inches, te m 3.1.3. Rock fills are defined as fills containing no rocks or hard lumps larger than 3 feet to in maximum dimension and containing little or no fines. Fines are defined as material smaller than 3/4 inch in maximum dimension. The quantity of fmes shall be less than approximately 20 percent of the rock fill quantity. GI rev. 8/98 ^ 3.2. Material of a perishable, spongy, or otherwise unsuitable nature as determined by the Consultant shall not be used in fills. to ^ 3.3. Materials used for fill, either imported or on-site, shall not contain hazardous materials as defmed by the Califomia Code ofRegulations, Title 22, Division 4, Chapter 30, Articles 9 ^ and 10; 40CFR; and any other applicable local, state or federal laws. The Consultant shall to * not be responsible for the identification or analysis of the potential presence of hazardous (P, materials. However, if observations, odors or soil discoloration cause Consultant to ^ suspect the presence of hazardous materials, the Consultant may request fi-om 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. 1^ 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 (horizontahvertical) and a soil layer no thicker than 12 inches is track-walked onto the face for landscaping purposes. IM This procedure may be utilized, provided it is acceptable to the goveming agency. Owner and Consultant. 3.5. Representative samples of soil materials to be used for fill shall 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 to notified immediately to evaluate the significance of the unanticipated condition ^ 4. CLEARING AND PREPARING AREAS TO BE FILLED in 4.1. Areas to be excavated and filled shall be cleared and gmbbed. Clearing shall consist of complete removal above the ground surface of trees, stumps, bmsh, vegetation, man-made m stmctures and similar debris. Gmbbing shall consist of removal of stumps, roots, buried to logs and other unsuitable material and shall be performed in areas to be graded. Roots and other projections exceeding 1-1/2 inches in diameter shall be removed to a depth of 3 feet below the surface of the ground. Borrow areas shall be gmbbed to the extent necessary to ^ provide suitable fill materials. Gl rev. 8/98 to 4.2. Any asphalt pavement material removed during clearing operations should be properly disposed at an approved ofT-site facility. .Concrete fiagments which 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. r te to te 4.3. After clearing and gmbbing of oi^anic matter or other unsuitable material, loose or porous soils shall be removed to the depth recommended in the Geotechnical Report The depth of removal and compaction shall be observed and approved by a representative of the Consultant. The exposed surface sfaaU then be plowed or scarified to a minimum depth of 6 inches and until the surface is fiee fix)m uneven features that would tend to prevent uniform compaction by the equipment to be used. 4.4. Where the slope ratio of the originai ground is steeper than 6:1 (horizontai.-vertical), or where recommended by the Consultant, the original ground should be benched in accordance with the following illustration. TYPICAL BENCHING DETAIL Rnish Grade Original Ground Rnish Slope Surface te to Remove All Unsuitable Material As Recommended By Soil Engineer Slope To Be Such That Sloughing Or Sliding Does Not Occur See Note 1 See Note 2 to to No Scale DETAIL NOTES: (1) Key width "B" should be a minimum of 10 feet wide, or sufficiently wide to permit complete cover^e with the compaction equipment used. The base ofthe key should be graded horizontal, or inclined slightly into the natural slope. (2) The outside ofthe bottom 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 fey the Consultant. GI rev. 8/98 to k to to 4.5. After areas to receive fill have been cleared, plowed or scarified, the surface should be disced or bladed by the Contractor until it is unifonn and fi'ee from large clods. The area should then be moisture conditioned to achieve the proper moisture content, and compacted as recommended in Section 6.0 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 pnetmiatic-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 fiil, 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 constmcted 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 as determined by ASTM D1557-91. 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. WTien the moisture content of the so;7 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. 8/98 to ll to ib to 6.1.5. After each layer has been placed, mixed, and spread evenly, it shall be thoroughly IM compacted by the Contractor to a relative compaction of at least 90 percent. 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 D1557-91. Compaction shall be continuous i* over the entire area, and compaction equipment shall make sufficient passes so that li the specified minimtun relative compaction has been achieved throughout the entire fill. to ite 6.1.6. Soils having an Expansion Index of greaterthan 50 may be used in fills if placed at to least 3 feet below finish pad grade and should be compacted at a moisture content to generally 2 to 4 percent greater than the optimimi moisture content for the 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 to least 3 feet and then cut to the design grade. This procedure is considered te preferable to track-walking of slopes, as described in the following paragraph. 1^ 6.1.8. As an altemative to over-building of slopes, slope faces may be back-rolled with a heavy-duty loaded sheepsfoot or vibratory roller at maxunum 4-foot fill height ^ intervals. Upon completion, slopes should then be track-walked with a D-8 dozer or similar equipment, such that a dozer track covers all siope surfaces at least ^ twice. to 6.2. Soil-rock fill, as defined in Paragraph 3.1.2, shall be placed by the Contractor in accordance with the following recommendations: to 6.2.1. Rocks larger than 12 inches but less than 4 feet in maximum dimension may be b incorporated into the compacted so/7 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. to pi 6.2.2. Rocks or rock fiagments up to 4 feet in maximum dimension may either be te 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 ip» shall be approved by the Consultant prior to placement. GI rev. 8/98 'to to to 6.2.3. For individual placement, sufficient space shall be provided between rocks to allow Ite for passage of compaction equipment. to to te 6.2.4. For windrow placement, the rocks should be placed in trenches excavated in properly compacted soil fill. Trenches shouid be approximately 5 feet wide and 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 should be compacted by fiooding. Windrows may aiso be placed utilizing an ^ "open-face" method in lieu of the trench procedure, however, this method should first be approved by the Consultant. to ^ 6.2.5. Wmdrows should generally be parallel to each other and may be placed either ^ 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 minimum vertical spacing between windrow courses shall be 2 feet from the top of a lower windrow to the bottom of the next higher pi, windrow. to 6.2.6. All rock placement, fill placement and flooding of approved granular soil in the ^ windrows must be continuously observed by the Consultant or his representative, to ^ 6.3. Rock fills, as defined in Section 3.1.3., shall be placed by the Contractor in accordance with ^ the following recommendations: m 6.3.1. The base of the rock fill shall be placed on a sloping surface (minimum slope of 2 percent, maximum slope of 5 percent). The surface shall slope toward suitable subdrainage outlet facilities. The rock fills shall be provided with subdrains during to constmction so that a hydrostatic pressure buildup does not develop. The subdrains shall be permanently cormected to controlled drainage facilities to ^ control post-constmction infiltration of water. to 6.3.2. Rock fills shall be placed in lifts not exceeding 3 feet. Placement shall be by rock ii tmcks traversing previously placed lifts and dumping at the edge of the currently 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 tmcks traversing in front of the current rock lift face and spraying ^ water continuously during rock placement. Compaction equipment witfi to compactive energy comparable to or greater tfian that of a 20-ton steel vibratory roller or other compaction equipment providing suitable energy to achieve the GI rev. 8/98 [ required compaction or deflection as recommended in Paragraph 6.3.3 shall be utilized. The number of passes to be made will be determined as described in Paragraph 6.3.3. Once a rock fill lift has been covered with soil fill, no additionai rock fill lifts will be permitted over the soil fill. 63.3. Plate bearing tests, in accordance with ASTM Dl 196-64, may be performed in both the compacted soil fill and in the rock fill to aid in determining the number of passes of the compaction equipment to be performed. If performed, a minimum of three plate bearing tests shall 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 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 defiection variation with number of passes. The required number of passes of the compaction 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 shall be present during rock fill operations to V verify that the minimum number of "passes" have been obtained, that water is being properly applied and that specified procedures are being followed. The pm actual number of plate bearing tests will be determined by the Consultant during ^ grading. In general, at least one test should be performed for each approximately 5,000 to 10,000 cubic yards of rockTiW placed. te 6.3.5. Test pits shall be excavated by the Contractor so that the Consultant can state that, in his 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. c 6.3.6. To reduce the potential for "piping" of fines into the rock fill itom overiying soil m fill material, a 2-foot layer of graded filter material shall be placed above the ki 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 l gradation of the graded filter material will be determined at the time the rock fill is te being excavated. Materials typical of the rock fill should be submitted to the »»• Consultant in a timely manner, to allow design of the graded filter prior to the to commencement of rock fill placement. Gi rev. 8/98 •to k to k to te 6.3.7. All rock fill placement shall be continuously observed during placement by representatives of the Consultant. 7. OBSERVATION AND TESTING 7.1. The Consultant shall be the Owners representative to observe and perfonn tests during clearing, gmbbing, filling and compaction operations. In general, no more than 2 feet in vertical elevation of soil or soil-rock fill shalt be placed without at least one field density test being performed within that interval. In addition, a minimum of one field density test shall be performed for every 2,000 cubic yards of soil or soil-rock fill placed and compacted. 7.2. The Consultant shal! perfonn random field density tests of the compacted soil or soil-rock fill to provide a basis for expressing an opinion as to 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 shall verify that the minimum number of passes have been obtained per the criteria discussed in Section 6.3.3. The Consultant shall 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 sufflcient moisture has been applied to the material. If performed, plate bearing tests will be performed randomly on the surface of the most-recently placed lift. Plate bearing tests will be performed to provide a basis for expressing an opinion as to whether the rock fill is adequately seated. The maximum defiection in the rock fill determined in Section 6.3.3 shall be less than the maximum defiection of the properly compacted soil fill. When any of the above criteria 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 Geotechnical Report or in the final report of testing and observation services performed during grading. GI rev. 8/98 to te to 7.5. The Consultant shall observe the placement of subdrains, to verify that the drainage devices hi have been placed and constmcted in substantial conformance with project specifications. m m 7.6. Testing procedures shall conform to the following Standards as appropnate: I! 7.6.1. Soil and Soil-Rock Fills: E 7.6.1.1. Field Density Test, ASTM D1556-82, Density of Soil In-Place By the Sand-Cone Method 7.6.1.2. Field Density Test, Nuclear Metfiod, ASTM D2922-81, Density of Soil and r* Soil-Aggregate In-Place by Nuclear Methods (Shallow Depth). to 7.6.1.3. Laboratory Compaction Test, ASTM D1557-91, Moisture-Density to Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound Hammer te and 18-Inch Drop. #i 7.6.1.4. Expansion Index Test, Uniform Building Code Standard 29-2, Expansion 1^ Index Test. p, 7.6.2. Rock Fills *• 7.6.2.1. Field Plate Bearing Test, ASTM Dl 196-64 (Reapproved 1977) Standard Methodfor Nonrepresentative Static Plate Load Tests of Soils and Flexible ^ Pavement Components, For Use in Evaluation and Design of Airport and te Highway Pavements. ^ 8. PROTECTION OF WORK to to 8.1. During constraction, 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 E Contractor shall take remedial measures to prevent erosion of freshly graded areas until such time as permanent drainage and erosion contro! features have been installed. Areas subjected to erosion or sedimentaticm shall be properly prepared in accordance with the F* Specifications prior to placing additional fill or stmctures. te im 8.2. After completion of grading as observed and tested by the Consultant, no further ite excavation or filling shall be conducted except in conjunction with the services of the Consultant. to te GI rev. 8/98 to k I to te to k 9. CERTIFICATIONS AND FINAL REPORTS 9.1. Upon completion of the work. Contractor shail fumish 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 Ae drain system is free of obstmctions. 9.2. The Owner is responsible for fiunishmg a final as-graded soil and geologic report satisfactory to the appropriate goveming or accepting agencies. The as-graded report should be prepared and signed by a Califonua licensed Civil Engineer experienced in geotechmcal engineering and by a Califomia Ortified Engineering Geologist, indicating that tiie geoteclmical aspects of the grading were performed in substantial conformance with the Specifications or ^proved changes to the Specifications. to te GI rev. 8/98 r APPENDIX D J SEISMIC REFRACTION SURVEY DATA - for ^ RANCHO SANTA FE ROAD REALIGNMENT STATION 252+00 TO MELROSE DRIVE CARLSBAD, CALIFORNIA PROJECT NO. 06535-22-01 SEISMIC REFRACTION SURVEY DATA c h to I. to te Two seismic refraction surveys were performed during previous investigations of the alignment. The seismic refraction surveys can be used to evaluate the rippability ofthe geologic materials in the area ofthe proposed cut slopes. Based on the results ofthe geophysical study, it appears that the depth to marginally rippable to non-rippable material is approxiinately 5 feet. Excavations beyond this depth will likely require heavy ripping and/or blasting to efficientiy excavate the materials. The approximate location of seismic refraction traverse S-19 is between Station 260+10 to 261+10 on the centeriine of the alignment (adjacent to HT-34) and S-20 was performed about 90 to 190 feet left of Station 258+90 (adjacent to T-80). SEISMIC TRAVERSES Seisnuc Traverse No. Average Velocity (ft^sec,) Average Depth (ft) Length of Traverse (ft.) Approximate Maximum Depth Explored (ft.) Seisnuc Traverse No. V, VI V3 D, D2 D3 Length of Traverse (ft.) Approximate Maximum Depth Explored (ft.) S-19 1120 5850 -5 100 30 S-20 1150 5830 -5 IOO 30 V, V3 D, D: D3 Velocity in feet per second of first layer of materials Second layer velocities Third layer velocities Depth in feet to base of first layer Depth to base of second layer Depth to base of tiiird layer k to te NOTE: For mass grading, materials wifli velocities of less than 4500 fps are generally rippable with a D9 Caterpillar Tractor equipped with a single shank hydraulic ripper. Velocities of 4500 to 5500 fps indicate marginal ripping and blasting. Velocities greater than 5500 fps generally require pre-blasting. For trenching, materials with velocities less than 3800 fps are generally rippable depending upon the degree of fracturing and the presence or absence of boulders. Velocities between 3800 and 4300 fps generaUy indicate marginal ripping, and velocities greater than 4300 fps generally indicate non-rippable conditions. The above velocities are based on a Kohring 505. The reported velocities represent average velocities over flie length of each traverse, and should not generally be used for subsurface inteipretation greater tiian 100 feet from a traverse. to te to te Project No. 06535-22-01 -D-1 -July 17, 2000 [ c to te to te r te to LIST OF REFERENCES 1. Blake, T. F., EQFAULT, A Computer Program for the Deterministic Prediction of Peak Horizontal Acceleration from Digitized Califomia Faults, Users Manual, 1989a, p. 79 (Revised 1993). 2. Califomia Department ofTransportation, 1986, Bridge Design Details Manual. 3. Califomia Department ofTransportation, 1986, Bridge Memo to Designers Manual. 4. Califomia Department ofTransportation, 1987, Bridge Design Specifications ManuaL 5. Califomia Department ofTransportation, 1995, Highway Design ManuaL 6. Califoraia Department ofTransportation, 1995, Standard Specifications. I. Preliminary Geotechnical Investigation, Villages of La Costa - The Oaks and Ridge, Carlsbad, California, Geocon Incorporated, January 10, 2000 (ProjectNo. 06105-12-01). 8. Bridge Foundation Investigation for Rancho Santa Fe Road Realignment, Rancho Santa Fe Bridge Crossing at San Marcos Creek, Carlsbad, Califomia, Geocon Incorporated, September 13,1990 (ProjectNo. 04367-05-03). 9. Geologic Map of the Northwestem Part of San Diego County, Califomia, Califomia Division of Mines and Geology, DMG Open-File Report 96-02, 1996. 10. Slemmons, D. B., 1982, Determination of Design Earthquake Magnitudes for Microzonation, Proceedings of Third Intemationai Microzonation Conference, Vol. 1. II. United States Geological Survey, 7.5 minute Quadrangle Series, Rancho Santa Fe Quadrangle, 1968, photorevised 1983. to te 12. Unpublished reports, aerial photographs and maps on file with Geocon hicorporated. to k ProjectNo. 06535-22-01 July 17, 2000