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HomeMy WebLinkAboutPIP 06-10; BRESSI RANCH INDUSTRIAL LOTS; GEOTECHNICAL INVESTIGATION PROPOSED BUSINESS PARK; 2006-05-18GEOTECHNICAL INVESTIGATION PROPOSED BUSINESS PARK % Bressi Ranch Lots 17-22 Planning Area 3 Carlsbad, California for Urban West Strategies 0 4 4 Southern California Geotechflical Urban West Strategies 1280 Bison Avenue, 139-609 Newport Beach, California 92660 Attention: Ms. Kimberly Hutchings Subject: Geotechnical Investigation Proposed Business Park Bressi Ranch Lots 17-22 Planning Area 3 NWC of Gateway Road and Innovation Way Carlsbad, California Gentlemen: May 18, 2006 Project No. 06G174-1 In accordance with your request, we have conducted a geotechnical investigation at the subject site. We are pleased to present this report summarizing the conclusions and recommendations developed from our investigation. We sincerely appreciate the opportunity to be of service on this project. We look forward to providing additional consulting services during the course of the project. If we may be of further assistance in any manner, please contact our office. Respectfully Submitted, Southern California Geotechnical, Inc. Robert G. Trazo, c., GE 2655 Senior Enaineer G. 01 2I \. No. 2655 J \ Exp.123l/O6 14L NAL CEG 2125 log ist .1 No. 2125 'CERTIFIO I Ditributii: )(5) Addressee 1260 North Hancock Street, Suite 101 -, Anaheim, California 92807-1951 • (714) 777-0333 • Fax (714) 777-0398 TABLE OF CONTENTS 1.0 EXECUTIVE SUMMARY 1 2.0 SCOPE OF SERVICES 3 3.0 SITE AND PROJECT DESCRIPTION 4 3.1 Site Description 4 3.2 Proposed Development 4 3.3 Previous Studies 5 4.0 SUBSURFACE EXPLORATION 9 4.1 Scope of Exploration/Sampling Methods 9 4.2 Geotechnical Conditions 9 4.3 Geologic Conditions 10 5.0 LABORATORY TESTING 11 6.0 CONCLUSIONS AND RECOMMENDATIONS 13 6.1 Seismic Design Considerations 13 6.2 Geotechnical Design Considerations 15 6.3 Site Grading Recommendations 17 6.4 Construction Considerations 21 6.5 Foundation Design and Construction 22 6.6 Floor Slab Design and Construction 24 6.7 Trash Enclosure Design Parameters 24 6.8 Retaining Wall Design Recommendations 25 6.8 Pavement Design Parameters 27 7.0 GENERAL COMMENTS 31 APPENDICES A Plate 1: Site Location Map Plate 2: Boring Location Plan B Boring Logs C Laboratory Test Results D Grading Guide Specifications E UBCSEIS Computer Program Output Southern California: Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 1.0 EXECUTIVE SUMMARY Presented below is a brief summary of the conclusions and recommendations of this investigation. Since this summary is not all inclusive, it should be read in complete context with the entire report. Site Preparation No significant topsoil or vegetation was present at the site at the time of the subsurface exploration. Any vegetation that develops prior to site grading should be stripped and removed from the site. The site is underlain by recently placed compacted fill soils and sandstone and claystone bedrock. The fill soils extend to depths of up to 50± feet within Planning Area 3 and were placed under the purview of a geotechnical engineer. The existing fill soils and bedrock possess relatively high strengths, and medium expansive potentials. A compaction report prepared by Leighton and Associates indicates that the existing fill soils were placed as compacted structural fill. Leighton indicates that the existing fill soils are suitable for support of the proposed development provided that the cut/fill transitions are mitigated during precise grading. Based on the expansive potentials and differing strengths of the engineered fill and bedrock, and in order to provide for a new layer of structural fill that will help mitigate the potential cut/fill transitions, it is recommended that remedial grading be performed within the proposed building pad areas. The building pad areas underlain by shallow bedrock (Proposed Buildings A, B, C, D, E, G, 9, and 10) should be overexcavated to a depth of at least 3 feet below existing grade and to a depth of at least 3 feet below proposed pad grade. The depth of overexcavation should be sufficient to provide at least 3 feet of new structural fill beneath the bearing grade of all foundations. In the remaining portions of the site, overexcavation should extend to a depth adequate to remove all surficial, weathered soils. Following completion of the recommended overexcavation, exposed soils should be evaluated by the geotechnical engineer. After the subgrade soils have been approved by the geotechnical engineer, the resulting soils may be replaced as compacted structural fill. A precise grading plan review is recommended subsequent to preparation of the plan in order to confirm the recommendations contained herein. Building Foundations Shallow foundations, supported in existing and/or newly placed compacted fill. 2,500 psf maximum allowable soil bearing pressure. Minimum longitudinal steel reinforcement within strip footings: Four (4) No. 5 rebars (2 top and 2 bottom), due to the medium expansive potential of the near surface soils. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Pagel Due to highly differential fill depths in the central and southeastern areas of the site, strip footings within Buildings 3, 4, 7, 8, 11, and G are recommended to be reinforced with six (6) No. 5 rebars (3 top and 3 bottom): Building Floor Slabs Slab-on-Grade, at least 5 inches thick. Minimum slab reinforcement: No. 3 bars at 18-inches on-center, in both directions. Due to the highly differential fill depths in the north central and southeastern areas of the site, floor slab reinforcement within Buildings 3, 4, 7, 8, 11, and G is recommended to consist of No. 4 bars at 18 inches on-center, in both directions. Pavements ASPHALT PAVEMENTS Thickness (inches) Materials Auto Parking Auto Drive Light Truck Moderate (TI = 4.0) Lanes Traffic Truck Traffic (TI = 5.0) (TI = 6.0) (TI = 7.0) Asphalt Concrete 3 3 31/2 4 Aggregate Base 6 9 11 13 Compacted Subgrade (90% 12 12 12 12 minimum _compaction) PORTLAND CEMENT CONCRETE PAVEMENTS Thickness (inches) Materials Automobile Parking Light Truck Traffic Moderate Truck and Drive Areas (TI = 6.0) Traffic (TI = 7.0) PCC 5 51/2 7 Compacted Subgrade 12 12 12 (95% minimum compaction) Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 0613174-1 Page 2 2.0 SCOPE OF SERVICES The scope of services performed for this project was in accordance with our Proposal No. 06P212, dated April 19, 2006. The scope of services included review of previous reports, a visual site reconnaissance, subsurface exploration, field and laboratory testing, and geotechnical engineering analysis to provide criteria for preparing design of the building foundations, building floor slabs, and parking lot pavements along with site preparation recommendations and construction considerations for the proposed development. The evaluation of environmental aspects of this site was beyond the scope of services for this geotechnical investigation. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA ' Project No. 06G174-1 - Page 3.0 SITE AND PROJECT DESCRIPTION 3.1 Site Description The subject site is located within the recently mass graded Bressi Ranch Industrial Park which is located south of Palomar Airport Road in the city of Carlsbad, California. The specific site is a portion of Planning Area 3 or Lots 17 though 22, and consists of 12± acres located northwest of the intersection of Gateway Road and Innovation Way. The general location of the site is illustrated on the Site Location Map, included as Plate I in Appendix A of this report. The subject site is an irregularly-shaped parcel, approximately 12± acres in size. Graded slopes ranging in height from 6 to 10± feet border the site to the north and east. A 12± foot high graded slope bisects the site. Isolated areas of stockpiled debris were scattered along the south central portion of the site. At the time of the subsurface exploration, ground surface cover consisted of exposed soil with negligible to sparse grass and weed growth. An existing de-silting basin is located near the southwestern corner of the site. Detailed topographic information was not available at the time of this report. Visually, with the exception of the aforementioned slopes, the remainder of the site consists of gently sloping terrain dipping downward to the southwest. With the exception of the aforementioned slopes, there was estimated to be less than 2 to 3± feet of elevation differential across the site. 3.2 Proposed Development A preliminary site plan was prepared by Ware Malcomb and provided to our office by the client. The plan indicates that the new development will consist of seventeen (17) one- and two-story buildings with total areas ranging from 4,500± ft2 to 16,800± ft2. Detailed structural information is not currently available. It is, however, assumed that the buildings will be of concrete tilt-up construction, typically supported on conventional shallow foundation systems and concrete slabs on grade. Based on the assumed construction, maximum column and wall loads are expected to be on the order of 60 kips and 3 kips per linear foot, respectively. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 3.3 Previous Studies As part of our investigation of the overall site, including Planning Areas PA-1 through PA-5, we were provided with several geotechnical reports. The geotechnical reports provided to us consist of preliminary and supplemental geotechnical investigations, a summary report of mass grading, and as graded reports of mass grading. The subject site has been recently rough graded to its current configuration under the purview of Leighton and Associates, Inc. The reports which are applicable to the entire site, including all of the Planning Areas, are summarized below: Geotechnical Investigation, Proposed Business Park, Bressi Ranch Lots 17-22, Planning Area 3, Carlsbad, California; prepared for St. Croix Capital by Southern California Geotechnical, Inc., dated August 22, 2005, Project No. 05G221-I. This report presents the results of our previous geotechnical investigation of the subject site. The work documented by this report occurred during the period of July 27, 2005 through August 22, 2005. This report states that twelve (12) borings were drilled within the site to depths ranging from 111/2 to 19%± feet. The maximum depth of the borings was limited to less than 20 feet due to permit restrictions imposed by the San Diego County Department of Environmental Health (DEH). The borings identified engineered fill soils extending to depths of 41/2 to at least 191/2± feet below existing grade. Below the fill soils, native alluvial soils were observed to the maximum depth explored of 191/2± feet below ground surface. Groundwater was reportedly not encountered in any of the borings or trenches. The report identified corrective grading removals of shallow bedrock for selected building pad areas (Buildings 17, 18 and the PCA building - all previously named buildings) on the order of 3 feet below existing grade and to a depth of 3 feet below proposed pad grade. In addition, the depth of overexcavation was recommended to provide at least 3 feet of new structural fill beneath the bearing grade of all foundations of the selected buildings. For the remaining buildings, the report recommended corrective grading to remove all surficial, weathered soils. Geotechnical Investigation, Bressi Ranch Corporate Center, Planning Areas I through 5, SEC of Palomar Airport Road and El Camino Real, Carlsbad, California; prepared for Sares Regis Group by Southern California Geotechnical, Inc., dated May 3, 2004, Project No. 03G259-2. This report presents the results of our geotechnical investigation of Planning Areas I through 5 subsequent to the mass grading. Subsurface exploration performed as part of this geotechnical investigation included twenty (20) borings advanced to depths of 5 to 191/2± feet below currently existing site grades. The maximum depth of the borings was limited to less than 20 feet due to permit restrictions imposed by the San Diego County Department of Environmental Health (DEH). Based on the subsurface conditions, the site is underlain by recently placed compacted fill soils and sandstone and claystone bedrock. The fill soils extend to depths of up to Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174..1 - Page 90± feet and were placed under the purview of a geotechnical engineer. The existing fill soils and bedrock possesses relatively high strengths, and highly variable expansive potentials. Based on the variable expansive potentials and differing strengths of the engineered fill and bedrock, and in order to provide for a new layer of structural fill that will help mitigate the potential cut/fill transitions, it was recommended that remedial grading be performed within the proposed building pad areas. The building pad areas were recommended to be overexcavated to a depth of at least 5 feet below existing grade and to a depth of at least 4 feet below proposed pad grade. The depth of overexcavation should be sufficient to provide at least 3 feet of new structural fill beneath the bearing grade of all foundations. Supplemental Geotechnical Investigation for Mass Grading, Bressi Ranch, Carlsbad, California, prepared for Lennar Homes by Leighton and Associates, Inc., dated March 14, 2001, Project No. 971009-005. This report presents the results of a supplemental geotechnical investigation to update their earlier preliminary geotechnical report prepared in 1997. Subsurface exploration performed as part of the supplemental geotechnical investigation included eight (8) large diameter borings and fifty-six (56) exploratory trenches. Logs of these supplemental borings and trenches as well as previous work by Leighton and others is included in the report and summarized on the Geotechnical Map included therein. Based on the presented information, the subject site is primarily underlain by sandstone bedrock. The bedrock is indicated to consist of the Tertiary age Santiago formation, which is described as massively bedded sandstone with some zones of claystone and siltstone. Some minor areas of shallow undocumented fill, terrace deposits, and alluvial/colluvial soils were also mapped within the boundaries of the subject site. Although the majority of the mapped, larger ancient landslides are located outside the boundaries of the subject site, two (2) small ancient landslides were mapped on the subject site, east of PA-1 and PA-2. Due to their small scale, they were recommended to be removed in their entirety and replaced as compacted fill. Remedial grading recommendations contained in this report indicate that all undocumented fill and alluvial/colluvial soils should be completely removed to competent material. Supplemental Geotechnical Landslide Investigation, Planning Areas PA-I, PA-2. and PA-10 through PA-I2, Bressi Ranch, Carlsbad, California, prepared for Lennar Communities by Leighton and Associates, Inc., dated February 12, 2003, Project No. 971009-007. This report presents the results of a supplemental geotechnical landslide investigation for specific portions of the site. Subsurface exploration performed as part of the supplemental geotechnical landslide investigation included nine (9) large diameter Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page borings and five (5) exploratory trenches in the areas of the previously mapped ancient landslides. Logs of these additional borings and trenches as well as revised cross sections are included in the report. The area of the subject site addressed by this report includes the eastern portion of planning areas PA-1 and PA-2 where several nested ancient landslides were mapped. Cross Sections E-E' and P-P' depict the mapped geologic conditions and the recommended remedial grading, which consisted of complete removal of the landslides and replacement as engineered fill. This report restates the previous remedial grading recommendations and provides slope stability calculations to justify the proposed grading configurations. Geotechnical Recommendations Concerning 95 Percent Relative Compaction of Fill Deeper than 40 Feet, Bressi Ranch, Carlsbad, California, prepared for Lennar Communities by Leighton and Associates, Inc., dated February 13, 2003, Project No. 971009-007. This report addresses the settlement potential of deep fill areas and provides recommendations to reduce the time period for the majority of the settlement to occur. In several areas of the overall project, fills up to 40 to 50± feet in thickness were planned to achieve the design grades. Deep fill areas on the subject site are located in the eastern portion of PA-2, and two small areas within PA-3 and PA-5. The report recommends that all structural fills below a depth of 40 feet from finish grade be compacted to at least 95 percent of the ASTM D-I557 maximum dry density, and estimates that the time period for the majority of the settlement to occur will be reduced from 6 to 12 months to 3 to 8+ months. Near surface settlement monuments were recommended to be installed immediately after rough grading, with survey intervals of once a week for the first month, then twice a month for 3 months, and then monthly to determine completion primary settlement of deep fills. The recommended locations of the near surface settlement monuments are indicated to be contained on an index map within this report, however, the copy provided to us does not contain this plan. Summary of the As-Graded Geotechnical Conditions and Partial Completion of Rough and Fine Grading, Planning Areas PA-1 Through PA-5, Bressi Ranch, Carlsbad, California, prepared for Lennar Communities by Leighton and Associates, Inc., dated January 20, 2004, Project No. 971009-014. This summary report indicates that grading of Planning Areas PA-1 through PA-3 is essentially complete, and that grading is ongoing in Planning Areas PA-4 and PA-5. Grading operations were reportedly performed in general accordance with the recommendations presented in Leighton's previous geotechnical reports. Geotechnical issues presented in this summary report which were not discussed in the previous reports include the presence of inactive faults within PA-4 and PA-5, perched groundwater within the overexcavated tributary canyons on the east side of PA-1 and PA-2, oversize materials within the engineered fills, high to very high expansive soils at Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 7 or near finish grade, and some severe sulfate concentrations which would require the use of specialized concrete mix designs. As Graded Report of Mass Grading, Planning Areas PA-1, PA-2, and PA-3, Metropolitan Street, and a Portion of Town Garden Road, Gateway Road, and Alicante Road, Carlsbad Tract No. 00-06, Bressi Ranch, Carlsbad, California, prepared for Lennar Communities by Leighton and Associates, Inc., dated April 15, 2004, Project No. 971009-014 This report documents the mass grading of Planning Areas PA-I, PA-2, and PA-3 as well as a portion of the interior streets. Most of the information contained in this report was presented in the January 20, 2004 summary report. The conclusions and recommendations are also similar to the previous report. With respect to the deep fills on this portion of the site, Leighton concluded that most of the anticipated settlement is complete, but the seven settlement monuments should be continued to be monitored. Soluble sulfate test results range from negligible to severe, and expansion index test results range from low (El = 46) to very high (El = 163). Preliminary pavement sections are presented and are based on assumed R-value of 12. Maximum cuts and fills within Planning Areas PA-1, PA-2, and PA-3 are documented as 25 and 90 feet, respectively. Fill soils below a depth of 40 feet were compacted to at least 95% of ASTM 1557 maximum dry density. Addendum to As-Graded Reports of Mass Grading Concerning the Completion of Settlement Monitoring, Planning Areas PA-1 through PA-5, Bressi Ranch, Carlsbad, California, prepared for Lennar Communities by Leighton and Associates, Inc., dated October 11, 2004, Project No. 971009-014 This report presents the data collected from the settlement monitoring program for the deep fill (greater than 40 feet) areas of the entire site. The settlement monitoring data was collected over a period of 5 to 6 months. Based on the collected data, Leighton concludes that the primary settlement of the fill soils is essentially complete, and that construction of improvements within Planning Areas PA-1 through PA-5 may begin. Secondary consolidation settlement of deep fills is estimated to be less than I to 3 inches depending on the depth of fill. Differential settlements are estimated to be on the order of % inch in 25 feet. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 4.0 SUBSURFACE EXPLORATION 4.1 Scope of Exploration/Sampling Methods The subsurface exploration conducted for this project consisted of thirteen (13) borings advanced to depths of 15 to 19'/2-+ feet below currently existing site grades. The maximum depth of our borings was limited to less than 20 feet due to permit restrictions imposed by the San Diego County Department of Environmental Health (DEH). All of the borings were logged during excavation by a member of our staff. Representative bulk and in-situ soil samples were taken during drilling. Relatively undisturbed in-situ samples were taken with a split barrel "California Sampler" containing a series of one inch long, 2.416± inch diameter brass rings. This sampling method is described in ASTM Test Method D-3550. In-situ samples were also taken using a 1.4± inch inside diameter split spoon sampler, in general accordance with ASTM 0-1586. Both of these samplers are driven into the ground with successive blows of a 140-pound weight falling 30 inches. The blow counts obtained during driving are recorded for further analysis. Bulk samples were taken at periodic locations in the trenches. The bulk samples were collected in plastic bags to retain their original moisture content. The relatively undisturbed ring samples were placed in molded plastic sleeves that were then sealed and transported to our laboratory. The approximate location of the borings are indicated on the Boring Location Plan, included as Plate 2 of this report. The Boring Logs, which illustrate the conditions encountered at the boring locations, as well as some of the results of the laboratory testing, are included in Appendix B. 4.2 Geotechnical Conditions Presented below is a generalized summary of the subsurface conditions encountered at the boring locations. More detailed descriptions of the conditions encountered are illustrated on the Boring Logs, included in Appendix B. Artificial Fill Artificial fill soils were encountered at the ground surface at boring locations B-I, B-3, B-4, B-5, B-6, and B-7. These fill soils extend to depths of 51/2 to at least 191/2 feet below existing grade, the maximum depth of our borings. As previously discussed, the fill soils within PA-3 are documented to have maximum depths of 40 to 50± feet. The fill soils encountered in the borings generally consist of stiff to very stiff, silty to sandy clays, and medium dense to dense silty sands, clayey sands and sandy silts. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 - Page Occasional samples of the fill materials possess minor debris content including bedrock fragments. The fill soils possess moderate to high strengths, moisture contents near or above optimum and based on their color mottling and composition, appeared to be well mixed. Bedrock Bedrock was encountered beneath the fill soils at twelve of the thirteen boring locations. The bedrock encountered at this site consists of Tertiary age Santiago formation, which is comprised of dense to very dense sandstone with some zones of claystone and siltstone. Bedding within the Santiago formation on site is generally massive with no significant planes of weakness or discontinuities. The sandstone unit is typically light gray in color, contains moderate iron oxide staining, and is comprised of weakly cemented silty fine sand. The siltstone unit is typically light gray to gray in color, contains moderate iron oxide staining, and is comprised of fine sandy silt. The claystone unit is typically dark gray to gray green in color, contains some shell fragments, gypsum veins, and is comprised of silts and clays. Groundwater Based on the water level measurements, and the moisture contents of the recovered soil samples, the static groundwater table is considered to have existed at a depth in excess of 191/2± feet at the time of the subsurface exploration. Further, based on the conditions documented in the mass grading report by Leighton, no groundwater was encountered during grading. Therefore, groundwater is expected to be at depths greater than the extent of the fill soils, which are 40 to 50± feet thick within PA-3. 4.3 Geologic Conditions Geologic research indicates that the site is underlain by sandstone mapped as the Santiago Formation (Map Symbol Tsa) with nearly horizontal bedding attitudes. The primary available reference applicable to the subject site is DMG Open-File Report 96- 02, Geologic Map of the Northwestern Part of San Diego County, California, by California Division of Mines and Geology, 1996. Based on the materials encountered in the exploratory borings, it is our opinion the site is underlain by sandstone, siltstone and claystone bedrock consisting of the Santiago formation (Map Symbol Tsa). The bedrock encountered in the exploratory borings and observed at the ground surface is generally massively bedded and the structure is comprised of nearly horizontal bedding with some moderately developed joints in the upper, less weathered portions of the bedrock. Southern California Geotechnical Proposed Lots 17.22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 10 5.0 LABORATORY. TESTING The soil samples recovered from the subsurface exploration were returned to our laboratory for further testing to determine selected physical and engineering properties of the soils. The tests are briefly discussed below. It should be noted that the test results are specific to the actual samples tested, and variations could be expected at other locations and depths. Classification All recovered soil samples were classified using the Unified Soil Classification System (USCS), in accordance with ASTM D-2488. Field identifications were then supplemented with additional visual classifications and/or by laboratory testing. The USCS classifications are shown on the Boring Logs and Trench Logs and are periodically referenced throughout this report. In-situ Density and Moisture Content The density has been determined for selected relatively undisturbed ring samples. These densities were determined in general accordance with the method presented in ASTM D-2937. The results are recorded as dry unit weight in pounds per cubic foot. The moisture contents are determined in accordance with ASTM D-2216, and are expressed as a percentage of the dry weight. These test results are presented on the Boring Logs. Consolidation Selected soil samples have been tested to determine their consolidation potential, in accordance with ASTM D-2435. The testing apparatus is designed to accept either natural or remolded samples in a one-inch high ring, approximately 2.416 inches in diameter. Each sample is then loaded incrementally in a geometric progression and the resulting deflection is recorded at selected time intervals. Porous stones are in contact with the top and bottom of the sample to permit the addition or release of pore water. The samples are typically inundated with water at an intermediate load to determine their potential for collapse or heave. The results of the consolidation testing are plotted on Plates C-I through C-5 in Appendix C of this report. Expansion Index The expansion potential of the on-site soils was determined in general accordance with Uniform Building Code (UBC) Standard 18-2. The testing apparatus is designed to accept a 4-inch diameter, 1-in high, remolded sample. The sample is initially remolded to 50± 1 percent saturation and then loaded with a surcharge equivalent to 144 pounds per square foot. The sample is then inundated with water, and allowed to swell against Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 Page 11 the surcharge. The resultant swell or consolidation is recorded after a 24-hour period. The results of the El testing are as follows: Sample Identification Expansion Index Expansive Potential B-7 @ 0 to 5 feet 71 Medium B-1O@0t05feet 55 Medium Soluble Sulfates Representative samples of the near-surface soils have been submitted to a subcontracted analytical laboratory for determination of soluble sulfate content. Soluble sulfates are naturally present in soils, and if the concentration is high enough, can result in degradation of concrete which comes into contact with these soils. The results of the soluble sulfate testing are not yet available. These test results, along with recommendations for any appropriate sulfate resistant concrete mix designs will be presented in an addendum report. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 12 6.0 CONCLUSIONS AND RECOMMENDATIONS Based on the results of our review, field exploration, laboratory testing and geotechnical analysis, the proposed development is considered feasible from a geotechnical standpoint. The recommendations contained in this report should be taken into the design, construction, and grading considerations. The recommendations are contingent upon all grading and foundation construction activities being monitored by the geotechnical engineer of record. The Grading Guide Specifications, included as Appendix 0, should be considered part of this report, and should be incorporated into the project specifications. The contractor and/or owner of the development should bring to the attention of the geotechnical engineer any conditions that differ from those stated in this report, or which may be detrimental for the development. Following completion of the recommended grading and foundation construction procedures, the subject site is considered suitable for its intended use. 6.1 Seismic Design Considerations The subject site is located in an area which is subject to strong ground motions due to earthquakes. The completion of a site specific seismic hazards analysis is beyond the scope of services for this geotechnical investigation. However, it should be noted that numerous faults capable of producing significant ground motions are located near the subject site. Due to economic considerations, it is not generally considered reasonable to design a structure that is not susceptible to earthquake damage. Therefore, significant damage to structures may be unavoidable during large earthquakes. The proposed structures should, however, be designed to resist structural collapse and thereby provide reasonable protection from serious injury, catastrophic property damage and loss of life. Faulting and Seismicity Research of available maps indicates that the subject site is not located within an Alquist-Priolo Earthquake Fault Zone. Therefore, the possibility of significant fault rupture on the site is considered to be low. Seismic Design Parameters The proposed development must be designed in accordance with the requirements of the latest edition of the Uniform Building Code (UBC) or the California Building Code (CBC), whichever is applicable. The UBC/CBC provides procedures for earthquake resistant structural design that include considerations for on-site soil conditions, seismic zoning, occupancy, and the configuration of the structure including the structural system and height. The seismic design parameters presented below are based on the seismic zone, soil profile, and the proximity of known faults with respect to the subject site. Southern California Geotechnical Proposed Lots 17-22 Business Park— Carlsbad, CA Project No. 06G174-1 - Page 13 The 1997 UBC/2001 CBC Design Parameters have been generated using UBCSEIS, a computer program published by Thomas F. Blake (January 1998). The table below is a compilation of the data provided by UBCSEIS, and represents the largest design values presented by each type of fault. A copy of the output generated from this program is included in Appendix E of this report. A copy of the Design Response Spectrum, as generated by UBCSEIS is also included in Appendix E. Based on this output, the following parameters may be utilized for the subject site: Nearest Type A Fault: Nearest Type B Fault: Soil Profile Type: Seismic Zone Factor (Z): Seismic Coefficient (Ca): Seismic Coefficient (Cu): Near-Source Factor (Na) Near-Source Factor (Ny) Elsinore-Julian (36 km) Rose Canyon (11 km) SD 0.40 0.44 0.64 1.0 1.0 The design procedures presented by the UBC and CBC are intended to protect life safety. Structures designed using these minimum design procedures may experience significant cosmetic damage and serious economic loss. The use of more conservative seismic design parameters would provide increased safety and a lower potential for cosmetic damage and economic loss during a large seismic event. Ultimately, the structural engineer and the project owner must determine what level of risk is acceptable and assign appropriate seismic values to be used in the design of the proposed structure. Liquefaction Liquefaction is the loss of strength in generally cohesionless, saturated soils when the pore-water pressure induced in the soil by a seismic event becomes equal to or exceeds the overburden pressure. The primary factors which influence the potential for liquefaction include groundwater table elevation, soil type and grain size characteristics, relative density of the soil, initial confining pressure, and intensity and duration of ground shaking. The depth within which the occurrence of liquefaction may impact surface improvements is generally identified as the upper 50 feet below the existing ground surface. Liquefaction potential is greater in saturated, loose, poorly graded fine sands with a mean (d50) grain size in the range of 0.075 to 0.2 mm (Seed and Idriss, 1971). Clayey (cohesive) soils or soils which possess clay particles (d<0.005mm) in excess of 20 percent (Seed and Idriss, 1982) are generally not considered to be susceptible to liquefaction, nor are those soils which are above the historic static groundwater table. The subsurface conditions encountered at the subject site are not conducive to liquefaction. These conditions consist of structural fill soils underlain by high strength Southern California Geotechnical Proposed Lots 17.22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 14 sandstone and claystone bedrock, neither of which are susceptible to earthquake- induced liquefaction. Based on the subsurface conditions, liquefaction is not considered to be a significant design concern for this project. 6.2 Geotechnical Design Considerations General The subject site is underlain by variable depths of compacted fill soils underlain by sandstone and claystone bedrock. The fill soils, extending to maximum depths of 40 to 50± feet within PA-3, generally consist of moderate strength silty to sandy clays, silty sands, clayey sands and sandy silts. Based on the compaction report prepared by Leighton and Associates, these fill materials represent compacted structural fills, placed during recent mass grading operations. Laboratory testing indicates that these materials possess generally favorable consolidation characteristics. However, the depth of fill soils varies significantly across the site and several cut/fill transitions between the fill and bedrock were created by the mass grading procedures. In addition, the proposed grading to establish the new finished floor elevations is expected to result in the formation of numerous additional cut/fill transitions. The resultant subsurface profile is expected to provide variable support characteristics for the foundations of the proposed structures. Based on these considerations, it is recommended that remedial grading be performed within the new building areas in order to provide a subgrade suitable for support of the foundations and floor slabs of the new structures. The primary geotechnical design considerations that will impact the proposed development are the presence of highly differential fill depths within some areas of the site, and the fact that the proposed grading will create cut/fill transitions within most of the proposed building areas. These considerations are discussed in detail in the following sections of this report. Grading and Foundation Plan Review The conclusions and recommendations presented in this report are based on the preliminary plans provided to our office. No grading plans were available at the time of this report. Once preliminary grading plans become available, it is recommended that they be provided to our office for review with regard to the conclusions and recommendations presented herein. In addition, a foundation plan was not available at the time of this report. It is recommended that preliminary foundation plans be provided to our office once they become available. Depending on the results of our review, some modifications to the recommendations contained in this report may be warranted. Differential Fill Depths Buildings 3, 4, 7, 8, 11, and G are underlain by significant differential fill depths, due to the previously completed mass grading. The fill depth differential within these buildings Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 15 is expected to be up to 15± feet. These buildings will require special geotechnical design considerations to reduce the potential effects of differential settlements that could be caused by the differential fill depths in this area of the site. These considerations include the use of additional steel reinforcement within the foundations and floor slabs of the affected structures. Settlement The results of the consolidation/collapse testing indicate that the existing fill soils are not subject to significant collapse upon moisture infiltration. In addition, the existing fill soils do not exhibit significant consolidation when exposed to load increases in the range of those that will be imposed by the new foundations. Provided that the recommendations contained within this report are implemented in the structural design and construction of the proposed buildings, the post-construction settlements are expected to be within tolerable limits. Based on our understanding of the proposed development, new fills in the areas of the existing deep fills are expected to be less than 5 or 6± feet, and will not induce significant new settlements. Following completion of the recommended grading, the post-construction static settlements are expected to be within tolerable limits. Settlement of Existina Fill Soils As discussed above, the subject site is underlain by engineered fill soils, extending to depths of up to 45 to 50± feet. These materials represent engineered fill soils, monitored during placement by Leighton. Minor amounts of additional settlement may occur due to secondary consolidation effects. The extent of secondary consolidation is difficult to assess precisely, but may be in the range of 0.1 to 0.2 percent of the fill thickness, thus settlements of 0.6± to 1.2± inches may occur. Cut/Fill Transitions Buildings A, B, C, D, E, G, 9, and 10 are closely underlain by dense bedrock. It is expected that cuts and fills of up to I to 3± feet will be necessary within these building areas to achieve the proposed subgrade elevations. Therefore, cut/fill transitions are expected to exist within these building areas after completion of the proposed grading. This cut/fill transition condition at bearing grade raises a potential for additional differential settlement. This report contains recommendations for additional remedial grading within these building pads to remove this cut/fill transition. It should be noted that the extent of areas that will require overexcavation to mitigate cut/fill transitions will depend upon the final grades that are established throughout the site. Therefore, the extent of this remedial grading may change, following our review of the preliminary grading plan. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 16 Expansion Most of the on-site soils consist of medium expansive soils and bedrock (El = 55 to 71). However, isolated areas of highly expansive soils may be present on the site. Based on the presence of expansive soils, special care should be taken to properly moisture condition and maintain adequate moisture content within all subgrade soils as well as newly placed fill soils. The foundation and floor slab design recommendations contained within this report are made in consideration of the expansion index test results. It is expected that significant blending of the on-site soils will occur during precise grading procedures, and that the resulting building pad subgrade soils will possess medium expansion potentials. It is recommended that additional expansion index testing be conducted at the completion of precise grading to verify the expansion potential of the as-graded building pads. Shrinkage/Subsidence Based on our experience with the on-site soils and rock materials, removal and recompaction of the existing near-surface engineered fill soils is estimated to result in average shrinkage or bulking of less than 5 percent. Where the existing bedrock is overexcavated and replaced as structural fill, bulking on the order of 0 to 5 percent is expected. Minor ground subsidence is expected to occur in the soils below the zone of removal due to settlement and machinery working. The subsidence is estimated to be 0.1 feet. These estimates may be used for grading in areas that are underlain by existing engineered fill soils. No significant subsidence will occur in areas that are immediately underlain by sandstone bedrock. These estimates are based on previous experience and the subsurface conditions encountered at the boring locations. The actual amount of subsidence is expected to be variable and will be dependant on the type of machinery used, repetitions of use, and dynamic effects, all of which are difficult to assess precisely. Setbacks In accordance with Uniform Building Code (UBC) requirements, all footings should maintain a minimum horizontal setback of H/3, where H equals the slope height, measured from the outside face of the footing to any descending slope face. This setback should not be less than 7 feet, nor need it be greater than 40 feet. 6.3 Site Grading Recommendations The grading recommendations presented below are based on the subsurface conditions encountered at the boring locations and our understanding of the proposed development. We recommend that all grading activities be completed in accordance Southern California Ceotecirnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 Page 17 with the Grading Guide Specifications included as Appendix D of this report, unless superseded by site specific recommendations presented below. Site Stripping The grading recommendations presented below are based on the subsurface conditions encountered at the boring locations and our understanding of the proposed development. We recommend that all grading activities be completed in accordance with the Grading Guide Specifications included as Appendix 0 of this report, unless superseded by site-specific recommendations presented below. Site Stripping and Demolition Initial site preparation should include stripping of any vegetation and organic debris. Based on conditions observed at the time of the subsurface exploration, no significant stripping of vegetation or topsoil is expected to be necessary. However, if vegetation develops subsequent to the date of our reconnaissance, it should be removed off site. Removal of the existing debris in the south central portion of the site is also recommended. Initial grading operations should also include abandonment of the existing detention basin, located in the south central portion of the site. Any softened soils, silt deposits, water, or other unsuitable materials should be removed from the detention basin. Removals should extend to a depth of suitable structural compacted fill soils or bedrock. Where the detention basins are located within proposed building areas, the building pad overexcavation recommendations should also be implemented. Treatment of Existing Soils: Building Pads As discussed above, remedial grading will be necessary in several of the building areas to mitigate potential cut/fill transitions that will exist at or near the proposed foundation bearing grade. Remedial grading should be performed within the areas of Buildings A, B, C, D, E, G, 9, and 10 to remove and replace a portion of the dense bedrock as engineered fill. The existing bedrock should be overexcavated to provide for a new layer of compacted structural fill, extending to a depth of at least 3 feet below proposed foundation bearing grade, throughout the building areas. Based on conditions encountered at the boring locations, it is expected that such overexcavation will be required throughout Building Buildings A, B, C, D, E, G, 9, and 10. In general, the overexcavations should extend at least 5 feet beyond the building perimeters. If the proposed structures incorporate any exterior columns (such as for a canopy or overhang) the area of overexcavation should also encompass these areas. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 - Page 18 Within areas of the proposed structures that do not require overexcavation per the recommendations presented above, it is recommended that the existing fills be overexcavated to a depth of at least 1 foot below existing grade, to remove any existing weathered and/or softened fill soils, as well as to prepare the subgrade for new fill placement. Following completion of the overexcavations, the subgrade soils (or bedrock) within the building areas should be evaluated by the geotechnical engineer to verify their suitability to serve as the structural fill subgrade, as well as to support the foundation loads of the new structure. This evaluation should include proofrolling with a heavy rubber-tired vehicle to identify any soft, loose or otherwise unstable soils that must be removed. Some localized areas of deeper excavation may be required if loose, porous, or low density soils are encountered at the bottom of the overexcavation. The exposed subgrade soils should then be scarified to a depth of 12 inches, moisture conditioned to 2 to 4 percent above optimum moisture content, and recompacted. Treatment of Existing Soils: Retaining Walls and Site Walls The existing soils within the areas of any proposed retaining walls underlain by less than 2 feet of existing engineered fill soils should be overexcavated to a depth of 2 feet below foundation bearing grade and replaced as compacted structural fill, as discussed above for the proposed building pad. Subgrade soils in areas of non-retaining site walls should be overexcavated to a depth of 1 foot below proposed bearing grade, if not underlain by at lest 1 foot of existing engineered fill soils. In both cases, the overexcavation subgrade soils should be evaluated by the geotechnical engineer prior to scarifying, moisture conditioning and recompacting the upper 12 inches of exposed subgrade soils. In areas where unsuitable fill soils are encountered at foundation subgrade level, additional overexcavation or deepened footings will be necessary. The previously excavated soils may then be replaced as compacted structural fill. Treatment of Existing Soils: Parking and Drive Areas Overexcavation of the existing fill soils in the new parking and drive areas is generally not considered warranted, with the exception of any areas where lower strength soils are identified by the geotechnical engineer during grading. Subgrade preparation in the remaining new parking areas should initially consist of completion of cuts where required. The geotechnical engineer should then evaluate the subgrade to identify any areas of unsuitable soils. Based on conditions observed at the site at the time of drilling, no significant overexcavation is expected to be necessary within the new parking areas. The subgrade soils should then be scarified to a depth of 12± inches, moisture conditioned to 2 to 4± percent above optimum, and recompacted to at least 90 percent of the ASTM D-1 557 maximum dry density. Depending upon the actual finished grades, which have not yet been established, portions of the parking lot subgrades may be immediately underlain by bedrock. These Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 19 materials may be used for direct pavement subgrade support. However, the owner and/or developer of the project should understand that minor amounts of reflective cracking and/or minor differential movements should be expected to occur near the location of the transitions between these bedrock materials and the adjacent engineered fill. If such cracking or minor differential movements within the pavements is not considered acceptable, additional overexcavation should be performed within the cut portions of the parking areas. Fill Placement Fill soils should be placed in thin (6± inches), near-horizontal lifts, moisture conditioned. to 2 to 4 percent above optimum moisture content, and compacted. On-site soils may be used for fill provided they are cleaned of any debris or oversized materials to the satisfaction of the geotechnical engineer. All grading and fill placement activities should be completed in accordance with the requirements of the Uniform Building Code and the grading code of the City of Carlsbad. All fill soils should be compacted to at least 90 percent of the ASTM D-1 557 maximum dry density. Fill soils should be well mixed. Compaction tests should be performed periodically by the geotechnical engineer as random verification of compaction and moisture content. These tests are intended to aid the contractor. Since the tests are taken at discrete locations and depths, they may not be indicative of the entire fill and therefore should not relieve the contractor of his responsibility to meet the job specifications. lmDorted Structural Fill All imported structural fill should consist of low expansive (El < 30), well graded soils possessing at least 10 percent fines (that portion of the sample passing the No. 200 sieve). Additional specifications for structural fill are presented in the Grading Guide Specifications, included as Appendix D. Utility Trench Backfill In general, all utility trench backfill should be compacted to at least 90 percent of the ASTM 0-1557 maximum dry density. As an alternative, a clean sand (minimum Sand Equivalent of 30) may be placed within trenches and flooded in place. Compacted trench backfill should conform to the requirements of the local grading code, and more restrictive requirements may be indicated by the City of Carlsbad. Materials used to backfill trenches should consist of well graded granular soils with a maximum particle size of 3 inches. All utility trench backfills should be witnessed by the geotechnical engineer. The trench backfill soils should be compaction tested where possible; probed and visually evaluated elsewhere. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 20 Utility trenches which parallel a footing, and extending below a lh:lv plane projected from the outside edge of the footing should be backfilled with structural fill soils, compacted to at least 90 percent of the ASTM D-1557 standard. Sand or pea gravel backfill, unless it is similar to the native soils, should not be used for these trenches. 6.4 Construction Considerations Moisture Sensitive Subarade Soils Some of the near surface soils possess appreciable silt and clay content and will become unstable if exposed to significant moisture infiltration or disturbance by construction traffic. In addition, based on their granular content, the on-site soils will also be susceptible to erosion. The site should, therefore, be graded to prevent ponding of surface water and to prevent water from running into excavations. Excavation Considerations Based on conditions encountered at the boring locations, the bedrock that underlies the subject site possesses a dense to very dense relative density, but is somewhat friable. It is expected that it will be feasible to utilize conventional grading equipment within the depths that were explored by the borings. However, some difficulty may be encountered during excavation, possibly requiring large single shank-equipped bulldozers, excavators, etc. The grading contractor should verify the need for special excavation equipment prior to bidding the project. Based on the presence of moderate granular content of the soils throughout the development area, minor to moderate caving of shallow excavations may occur. Flattened excavation slopes may be sufficient to mitigate caving of shallow excavations, although deeper excavations may require some form of external stabilization such as shoring or bracing. Temporary excavation slopes should be no steeper than lh:lv. All excavation activities on this site should be conducted in accordance with Cal-OSHA regulations. Expansive Soils As previously discussed, the on site soils have been determined to possess a medium to potentially high expansion potential. It is recommended that the highly expansive soils be blended with less expansive soils to create structural fills with a low to medium expansive potential (El <90), or removed and placed in non structural areas. Therefore, care should be given to proper moisture conditioning of all building pad subgrade soils to a moisture content of 2 to 4 percent above the Modified Proctor optimum during site grading. All imported fill soils should have low to medium expansive characteristics. In addition to adequately moisture conditioning the subgrade soils and fill soils during grading, special care must be taken to maintain the moisture content of these soils at 2 to 4 percent above the Modified Proctor optimum. This will require the contractor to Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 21 frequently moisture condition these soils throughout the grading process, unless grading occurs during a period of relatively wet weather. Groundwater Free water was not encountered within the depths explored by the borings drilled for this project. These borings extended to a maximum depth of 191/2± feet below existing grade. Based on this information, groundwater is not expected to impact the proposed grading or foundation construction activities. 6.5 Foundation Design and Construction Based on the preceding preliminary grading recommendations, it is assumed that the new building pads will be immediately underlain by existing or newly placed structural fill soils extending to depths of at least 3± feet below foundation bearing grade. Based on this subsurface profile, the proposed structures may be supported on conventional shallow foundation systems. Foundation Design Parameters New square and rectangular footings may be designed as follows: Maximum, net allowable soil bearing pressure: 2,500 lbs/ft2. The allowable bearing pressure may be increased by 1/3 when considering short duration wind or seismic loads. . Minimum wall/column footing width: 14 inches/24 inches Minimum longitudinal steel reinforcement within strip footings: Four (4) No. 5 rebars (2 top and 2 bottom), due to medium expansive potential of near surface soils. Due to highly differential fill depths in the central and southeastern areas of the site, strip footings within Buildings 3, 4, 7, 8, and G are recommended to be reinforced with six (6) No. 5 rebars (3 top and 3 bottom): Minimum foundation embedment: 12 inches into suitable structural fill soils, and at least 18 inches below adjacent exterior grade. Interior column footings may be placed immediately beneath the floor slab. It is recommended that the perimeter foundations be continuous across all exterior doorways. Flatwork adjacent to exterior doors should be doweled into the perimeter foundations in a manner determined by the structural engineer. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 - Page 22 The minimum steel reinforcement recommended above is based on geotechnical considerations. Additional reinforcement may be necessary for structural considerations. The actual design of the foundations should be determined by the structural engineer. Foundation Construction The foundation subgrade soils should be evaluated at the time of overexcavation, as discussed in Section 6.3 of this report. It is further recommended that the foundation subgrade soils be evaluated by the geotechnical engineer immediately prior to steel or concrete placement. Soils suitable for direct foundation support should consist of newly placed structural fill, compacted to at least 90 percent of the ASTM D-1557 maximum dry density. Any unsuitable bearing materials should be removed to a depth of suitable bearing compacted structural fill, with the resulting excavations backfilled with compacted fill soils. As an alternative, lean concrete slurry (500 to 1,500 psi) may be used to backfill such isolated overexcavations. The foundation subgrade soils should also be properly moisture conditioned to 2 to 4 percent above the Modified Proctor optimum, to a depth of at least 12 inches below bearing grade. Estimated Foundation Settlements The proposed structures will experience settlements due to two primary factors: 1) the elastic settlements caused by deformation of the existing structural fill soils due to the loads imposed by the new foundations; and 2) long term settlement of the existing structural fill soils under their own weight. The total and differential settlements induced by the foundation loads of the new structures are estimated to be less than 1.0 and 0.5 inches, respectively, for shallow foundations designed and constructed in accordance with the recommendations provided in this report. The differential movements are expected to occur over a 30-foot span, thereby resulting in an angular distortion of less than 0.002 inches per inch. As discussed in Section 6.2 of this report, the long term settlements associated with the relatively deep existing fill soils could be on the order of 0.1 to 0.2 percent of the fill depth. On a preliminary basis, there may be up to 15± feet of differential fill depth across Building Pads 3, 4, 7, 8, 11, and G. This could result in differential settlements on the order of 0.2 to 0.4± inches. However, these differential settlements will occur over a distances of 50± feet, causing angular distortions on the order of 1/2 inch in 50 feet. Lateral Load Resistance Lateral load resistance will be developed by a combination of friction acting at the base of foundations and slabs and the passive earth pressure developed by footings below grade. The following friction and passive pressure may be used to resist lateral forces: Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 23 Passive Earth Pressure: 250 lbs/ft3 Friction Coefficient: 0.25 These are allowable values, and include a factor of safety. When combining friction and passive resistance, the passive pressure component should be reduced by one-third. These values assume that footings will be poured directly against suitable compacted structural fill. The maximum allowable passive pressure is 2500 lbs/ft2. 6.6 Floor Slab Design and Construction Subgrades which will support new floor slabs should be prepared in accordance with the recommendations contained in the Site Grading Recommendations section of this report. Based on the anticipated grading which will occur at this site, the floors of the new structures may be constructed as conventional slabs-on-grade supported on newly placed structural fill. Based on geotechnical considerations, the floor slabs may be designed as follows: Minimum slab thickness: 5 inches Minimum slab reinforcement: No. 3 bars at 18-inches on-center, in both directions. Due to the highly differential fill depths in the north central and southeastern areas of the site, floor slab reinforcement within Buildings 3, 4, 7, 8, 11, and G is recommended to consist of No. 4 bars at 18 inches on-center, in both directions. Slab underlayment: 10-mil vapor barrier, overlain by 2 inches of clean sand. Where moisture sensitive floor coverings are not anticipated, the vapor barrier and 2-inch layer of sand may be eliminated. Moisture condition the floor slab subgrade soils to 2 to 4 percent above optimum moisture content, to a depth of 12 inches. Proper concrete curing techniques should be utilized to reduce the potential for slab curling or the formation of excessive shrinkage cracks. 6.7 Trash Enclosure Design Parameters Based on the base map provided to us by the client, the proposed development includes several trash enclosures. It is expected that the trash enclosure as well as the approach slab will be subjected to relatively heavy wheel loads, imposed by trash removal equipment. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 24 The subgrade soils in the area of the trash enclosures and the approach slab should be prepared in accordance with the recommendations for the parking areas, presented in Section 6.3 of this report. As such, it is expected that the trash enclosures will be underlain by structural fill soils, extending to a depth of 1 foot below proposed subgrade elevation. Based on geotechnical considerations, the following recommendations are provided for the design of the trash enclosures and the trash enclosure approach slabs: The trash enclosures may consist of a 6-inch thick concrete slab incorporating a perimeter footing or a turned down edge, extending to a depth of at least 12 inches below adjacent finished grade. If the trash enclosures will incorporate rigid walls such as masonry block or tilt-up concrete, the perimeter foundations should be designed in accordance with the recommendations previously presented in Section 6.5 of this report. Reinforcement within the trash enclosure slabs should consist of at least No. 3 bars at 18-inches on-center, in both directions. The trash enclosure approach slabs should be constructed of Portland cement concrete, at least 6 inches in thickness. Reinforcement within the approach slabs should consist of at least No. 3 bars at 18-inches on-center, in both directions. The trash enclosure and approach slab subgrades should be moisture conditioned to within 2± percent of optimum moisture content to a depth of 12 inches. The trash enclosure slab and the approach slab should be structurally connected, to reduce the potential for differential movement between the two slabs. The actual design of the trash enclosures and the trash enclosure approach slabs should be completed by the structural engineer to verify adequate thickness and reinforcement. 6.8 Retaining Wall Design Recommendations It is expected that some small retaining walls may be required to facilitate the new site grades. The parameters recommended for use in the design of these walls are presented below. Retaining Wall Design Parameters Based on the soil conditions encountered at the boring locations, the following parameters may be used in the design of new retaining walls for this site. We have provided parameters for two different types of wall backfill: on-site silty clays, sandy clays, silty sands, clayey sands and sandy silts; and imported select granular material. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 25 In order to use the design parameters for the imported select fill, this material must be placed within the entire active failure wedge. This wedge is defined as extending from the base of the retaining wall upwards at a 59 degree angle of inclination. RETAINING WALL DESIGN PARAMETERS Soil Type Design Parameter Imported On-Site Aggregate Base Soils Internal Friction Angle (4)) 380 280 Unit Weight 130 lbs/ft3 125 lbs/ft3 Active Condition (level_backfill) 31 lbs/ft3 45 lbs/ft3 Equivalent Fluid Pressure: Active Condition (2h:1v backfill) 44 lbs/ft3 79 lbs/ft3 At-Rest Condition (level_backfill) 48 lbs/ft3 66 lbs/ft3 Regardless of the backfill type, the walls should be designed using a soil-footing coefficient of friction of 0.25 and an equivalent passive pressure of 250 lbs/ft3. The active earth pressures may be used for the design of retaining walls which do not directly support structures or support soils which in turn support structures and which will be allowed to deflect. The at-rest earth pressures should be used for walls which will not be allowed to deflect such as those which will support foundation bearing soils, or which will support foundation loads directly. Where the soils on the toe side of the retaining wall are not covered by a "hard" surface such as a structure or pavement, the upper 1 foot of soil should be neglected when calculating passive resistance due to the potential for the material to become disturbed or degraded during the life of the structure. Retaining Wall Foundation Design Retaining walls should be supported within newly placed structural fill monitored during placement by the geotechnical engineer. Where retaining walls are also serving as building walls, they should be graded in accordance with the recommendations presented in Section 6.3 of this report for the proposed building pad areas. Foundations to support new retaining walls should be designed in accordance with the general Foundation Design Parameters presented in a previous section of this report. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 26 Backfill Material It is recommended that a minimum 1 foot thick layer of free-draining granular material (less than 5 percent passing the No. 200 sieve) should be placed against the face of the retaining walls. This material should be approved by the geotechnical engineer. A suitable geotextile should be used to separate the layer of free draining granular material from the backfill soils. If the layer of free-draining material is not covered by an impermeable surface, such as a structure or pavement, a 12-inch thick layer of a low permeability soil should be placed over the backfill to reduce surface water migration to the underlying soils. All retaining wall backfill should be placed and compacted under engineering controlled conditions in the necessary layer thicknesses to ensure an in-place density between 90 and 93 percent of the maximum dry density as determined by the Modified Proctor test (ASTM D1557-91). Care should be taken to avoid over-compaction of the soils behind the retaining walls, and the use of heavy compaction equipment should be avoided. Subsurface Drainage As previously indicated, the retaining wall design parameters are based upon drained backfill conditions. Consequently, some form of permanent drainage system will be necessary in conjunction with the appropriate backfill material. Subsurface drainage may consist of either: A weep hole drainage system typically consisting of a series of 4-inch diameter holes in the wall situated slightly above the ground surface elevation on the exposed side of the wall and at an approximate 8-foot on-center spacing. The weep holes should include a minimum 2 cubic foot gravel pocket surrounded by an appropriate geotextile fabric at each weep hole location. A 4-inch diameter perforated pipe surrounded by 2 cubic feet of gravel per linear foot of drain placed behind the retaining wall, above the footing. The gravel drain should be wrapped in a suitable geotextile fabric to reduce the potential for migration of fines. The footing drain should be extended to daylight or tied into a storm drainage system. 6.8 Pavement Design Parameters Site preparation in the pavement area should be completed as previously recommended in the Site Grading Recommendations section of this report. The subsequent preliminary pavement recommendations assume proper drainage and construction monitoring, and are based on either PCA or CALTRANS design parameters for a twenty (20) year design period. These preliminary designs also Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 27 assume a routine pavement maintenance program to obtain the 20-year pavement service life. Pavement Sub-grades It is anticipated that the new pavements will be primarily supported on a layer of compacted structural fill, consisting of scarified, thoroughly moisture conditioned and recompacted native materials and/or fill soils. The on-site soils generally consist of sandy clays and sandy clays. These soils are considered to possess fair pavement support characteristics with R-values of 10 to 20. Since R-value testing was not included in the scope of services for this project, the subsequent pavement design is based upon an assumed R-value of 15. Any fill material imported to the site should have support characteristics equal to or greater than that of the on-site soils and be placed and compacted under engineering controlled conditions. It is recommended that R-value testing be performed after completion of rough grading. Depending upon the results of the R-value testing, it may be feasible to use thinner pavement sections in some areas of the site. AsDhattic Concrete The pavement designs are based on the traffic indices (Ti's) indicated. The client and/or civil engineer should verify that these Ti's are representative of the anticipated traffic volumes. If the client and/or civil engineer determine that the expected traffic volume will exceed those recommended herein, we should be contacted for supplementary recommendations. The design traffic indices equate to the following approximate daily traffic volumes over a 20-year design life, assuming 5 operational traffic days per week: Traffic index No. of Heavy Trucks per Day 4.0 0 5.0 1 6.0 3 7.0 11 For the purposes of the traffic volumes above, a truck is defined as a 5-axle tractor- trailer unit, with one 8-kip axle and two 32-kip tandem axles. All of the traffic indices allow for 1000 automobiles per day. Presented below are the recommended thicknesses for new flexible pavement structures consisting of asphaltic concrete over a granular base. It should be noted that the Ti = 5.0 section only allows for I truck per day. Therefore, all significant heavy truck traffic must be excluded from areas where this thinner pavement section is used; otherwise premature pavement distress may occur. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 28 ASPHALT PAVEMENTS Thickness (inches) Materials Auto Parking Auto Drive Light Truck Moderate (TI = 4.0) Lanes Traffic Truck Traffic (TI = 5.0) (TI = 6.0) (TI = 7.0) Asphalt Concrete 3 3 31/2 4 Aggregate Base 6 9 11 13 Compacted Subgrade (90% 12 12 12 12 minimum _compaction) The aggregate base course should be compacted to at least 95 percent of the ASTM D- 1557 maximum dry density. The asphaltic concrete should be compacted to at least 95 percent of the Marshall maximum density, as determined by ASTM D-2726. The aggregate base course may consist of crushed aggregate base (CAB) or crushed miscellaneous base (CMB), which is a recycled gravel, asphalt and concrete material. The gradation, R-Value, Sand Equivalent, and Percentage Wear of the CAB or CMB should comply with appropriate specifications contained in the current edition of the "Greenbook" Standard Specifications for Public Works Construction. Portland Cement Concrete The preparation of the subgrade soils within concrete pavement areas should be performed as previously described for proposed asphalt pavement areas. Since significant portions of the granitic bedrock are expected to be removed around the perimeters of the proposed structures where the Portland cement concrete pavements will be located, the pavement design presented below is based on the presence of existing or newly placed compacted structural fill immediately beneath the proposed pavement subgrade elevation. The minimum recommended thicknesses for the Portland Cement Concrete pavement sections are as follows: PORTLAND CEMENT CONCRETE PAVEMENTS Materials Thickness (Inches) Automobile Parking and Drive Areas Light Truck Traffic (TI = 6.0) Moderate Truck Traffic (TI = 7.0) PCC 5 5¼ 7 Compacted Subgrade (95% minimum compaction) 12 12 12 The concrete should have a 28-day compressive strength of at least 3,000 psi. Reinforcing within all pavements should consist of at least heavy welded wire mesh (6x6-W2.9xW2.9 WWF) placed at mid-height in the slab. In areas underlain by expansive soils, the reinforcement should be increased to No. 4 bars at 18 inches on Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 - Page 29 center. The maximum joint spacing within all of the PCC pavements is recommended to be equal to or less than 30 times the pavement thickness. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA Project No. 06G174-1 Page 30 7.0 GENERAL COMMENTS This report has been prepared as an instrument of service for use by the client in order to aid in the evaluation of this property and to assist the architects and engineers in the design and preparation of the project plans and specifications. This report may be provided to the contractor(s) and other design consultants to disclose information relative to the project. However, this report is not intended to be utilized as a specification in and of itself, without appropriate interpretation by the project architect, structural engineer, and/or civil engineer. The reproduction and distribution of this report must be authorized by the client and Southern California Geotechnical, Inc. Furthermore, any reliance on this report by an unauthorized third party is at such party's sole risk, and we accept no responsibility for damage or loss which may occur. The analysis of this site was based on a subsurface profile interpolated from limited discrete soil samples. While the materials encountered in the project area are considered to be representative of the total area, some variations should be expected between boring locations and sample depths. If the conditions encountered during construction vary significantly from those detailed herein, we should be contacted immediately to determine if the conditions alter the recommendations contained herein. This report has been based on assumed or provided characteristics of the proposed development. It is recommended that the owner, client, architect, structural engineer, and civil engineer carefully review these assumptions to ensure that they are consistent with the characteristics of the proposed development. If discrepancies exist, they should be brought to our attention to verify that they do not affect the conclusions and recommendations contained herein. We also recommend that the project plans and specifications be submitted to our office for review to verify that our recommendations have been correctly interpreted. The analysis, conclusions, and recommendations contained within this report have been promulgated in accordance with generally accepted professional geotechnical engineering practice. No other warranty is implied or expressed. Southern California Geotechnical Proposed Lots 17-22 Business Park - Carlsbad, CA - Project No. 06G174-1 Page 31 APPENDIX A SITE LOCATION MAP BORING LOCATION PLAN 7 CAL OR TA 5OR2ü, $5 .0 PORT /L 011 08 848 L8CQ 14RRDR8 ..[T..... 139201~LI 44 I C CARLSBAD 18 RACEWAY 7 .-R PALO AR lllHo RAW I HAWK 7 ' 2$ AIRPO MCCLELLAN I 2808 RD 7Y A0280A I 00 7 226022 40801 22620222 C .( 2 / 1 EEH2 R A 2 220(0 212262 JLC\R 821(022261 10062650 16210 7 2222122 1221) coees CT CA SCAt'I r: 2822 RJOC VITA kARL7 ( D C A LAS ALMAS ORE A87 C28411 Cl 22 1 222 P21R4 0 2282282 0 22221 c%08 1l-7 <0 / LA EL PAlO .. C'2"TARRIOL - RA21CH0E908RIA 6 62 C 2 2 20 23 C LK $20 24C 4 2 22 Or c' C " 847, oo cs p u ( 1 200 ' RESORT SA C0IR 200 8024022 / 4 '2cR <0s >DCIER 'r'OCt2 o114'26 3 VIA 0002<8.,. 7.45I 4.o8.ER8o0 0 .s/8.o rsAAS<241118, 11 SO ' 2 R- 'RTo0C'4EHA (5 56526 o2C: O47,404 TIARA " PKDS LA O j/ 1 .4 c1C 765$,80'2 IRSE • 1' 622 00 4A ' 7,7, 2 I 622 5(100162' 2286242'#0122o CA 55557 en loU srlo RD RD II 11 I 5HQU CANTE 4'SOA 50c DRf <0 COSTA •.: 26 RESORT 12 I - - 36 TA '4 ,l55 `ALE 'B 60 , T/ IT EYSTONE 1466 A~ ob AI URI 4 PA 10 ENSILLAR v All' Wal. IN AV 'VI T11A11 !E5T 4R 45 po Li AkARA Ile 411 NGB Boo 5-111 , LA -34 SITE LOCATION MAP j\ BRESSI RANCH LOTS 17 - 22, PA 3 CARLSBAD, CALIFORNIA 4 SOURCE: SAN DIEGO COUNTY 1" = 2400' Southern California Geotechnical THOMAS GUIDE, 2006 DRAWN: JJB J CHKD: ROT SCG PROJECT 06G174-1 1260 North Hancock Street, Suite 101 Anaheim, California 92807 PLATE I Phone: (714) 777-0333 Fax: (714) 777-0398 APPENDIX B BORING LOGS BORING LOG LEGEND SAMPLE TYPE GRAPHICAL SAMPLE DESCRIPTION SYMBOL AUGER SAMPLE COLLECTED FROM AUGER CUTTINGS, NO FIELD MEASUREMENT OF SOIL STRENGTH. I STURBEDROCK CORE EN WITH A DIAMOND-TIPPED CORE BARREL TYPICALLY USED COREt1 ONLY IN HIGHLY CONSOLIDATED BEDROCK. GRAB SOIL SAMPLE TAKEN WITH NO SPECIALIZED EQUIPMENT, SUCH AS FROM A STOCKPILE OR THE GROUND SURFACE. (DISTURBED) CAUFORNIA SAMPLER: 2-112 INCH I.D. SPLIT CS BARREL SAMPLER, LINED WITH 1-INCH HIGH BRASS RINGS. DRIVEN WITH SPT HAMMER. (RELATIVELY UNDISTURBED) NO RECOVER: THE SAMPLING ATTEMPT DID NOT N SR (I) RESULT IN RECOVERY OF ANY SIGNIFICANT SOIL OR ROCK MATERIAL- SPT .I1I><zZIT STANDARD PENETRATION TEST: SAMPLER IS 1.4 INCH INSIDE DIAMETER SPLIT BARREL, DRIVEN 18 INCHES WITH THE SPT HAMMER. (DISTURBED) SHEBLY TUBE: TAKEN WITH A THIN WALl. SAMPLE SH TUBE, PUSHED INTO THE SOIL AND THEN EXTRACTED. (UNDISTURBED) VANE ' [J VANE SHEAR TEST: SOIL STRENGH OBTAINED USING A 4 BLADED SHEAR DEVICE. TYPICALLY USED IN SOFT CLAYS-NO SAMPLE RECOVERED. COLUMN DESCRIPTIONS DEPTH: Distance in feet below the ground Surface. SAMPLE: Sample Type as depicted above. BLOW COUNT: Number of blow required to advance the sampler 12 inches using a 140 lb hammer with a 30-inch drop. 50/3" indicates penetration refusal (>50 blows) at 3 inches. WH indicates that the weight of the hammer was sufficient to push the sampler 6 inches or more. Approximate shear strength of a cohesive soil sample as measured by pocket penetrometer. Graphic Soil Symbol as depicted on the following page. Dry density of an undisturbed or relatively undisturbed sample. Moisture content of a soil sample, expressed as a percentage of the dry weight. The moisture content above which a soil behaves as a liquid. The moisture content above which a soil behaves as a plastic. The percentage of the sample finer than the #200 standard sieve. The shear Strength of a cohesive soil sample, as measured in the unconfined state. POCKET PEN. GRAPHIC LOG: DRY DENSITY: MOISTURE CONTENT: LIQUID LIMIT:. PLASTIC LIMIT: PASSING #200 SIEVE: UNCONFINED SHEAR: SOIL CLASSIFICATION CHART MAJOR DIVISIONS SYMBOLS. TYPICAL DESCRIPTIONS GRAPH LETTER GRAVEL CLEAN GRAVELS '$'? 1 AND GW WELL-GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES GRAVELLY SOILS (LITTLE OR NO FINES) U ba oZ~'o< GP POORLY-GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES COARSE GRAINED SOILS MORE THAN 50% OF COARSE FRACTION GRAVELS WITH FINES OCYL ol °o PO< ,a SILTY GRAVELS, GRAVEL- SAND - SILT MIXTURES RETAINED ON NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) 4 GC CLAYEY GRAVELS, GRAVEL - SAND - CLAY MIXTURES SAND CLEAN SANDS AND %AI WELL-GRADED SANDS GRAVELLY SANDS, LITTLE OR NO FINES MORE THAN 50% OF MATERIAL IS LARGER THAN SANDY NO. 200 SIEVE SIZE SOILS" (LITTLE OR NO FINES) : .°. :.• SP POORLY-GRADED SANDS, GRAVELLY SAND, LITTLE OR NO FINES SANDS WiTH FINES I SM SILTY SANDS SAND SILT MIXTURES MORE THAN 50% OF COARSE FRACTION / PASSING ON NO 4 SIEVE AMOUNT OF FINES) SC CLAYEY SANDS, SAND - CLAY I I I INORGANIC SILTS AND VERY FINE I I I I I I 'u"- SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY CL INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS FINE GRAINED SOILS SILTS AND LIQUID LIMIT CLAYS LESS THAN 50 OL ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY MORE THAN 50% OF MATERIAL IS NO. 200 SIEVE SMALLER THAN S MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE SAND OR SILTY SOILS' SIZE SILTS LIQUID LIMIT AND GREATER THAN 50 CLAYS U '' INORGANIC CLAYS OF HIGH PLASTICITY r'u '-'n ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS • S HIGHLY ORGANIC SOILS ,.,PT PEAT, HUMUS, SWAMP SOILS WITH HIGH ORGANIC CONTENTS NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS Southern California Geotechnical I!'. ---- - BORING NO. B-I JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 18 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS a c DESCRIPTION SURFACE ELEVATION: - MSL LABORATORY RESULTS W 0 0 p. W W a- 1 W D - W < Cl) - Z 0 0 _i to - a. . ° 00. o o o a. o ZZa co o5 . I to. - FILL: Mottled Light Brown to Gray Green fine Sandy Clay, 3.5 . stiff-moist 26 x 9 12 3.0 25 5— 12 4.25 21 >< 50/1" 4.25 14 SANTIAGO FORMATION BEDROCK: Gray Brown fine Sandy Claystone, very stiff to hard-damp to moist 17 15 10- SANTIAGO FORMATION BEDROCK: Gray Brown fine Sandy Claystone, hard-damp to moist 36 17 15 - SANTIAGO FORMATION BEDROCK: Gray Green fine Sandy Claystone, very stiff-moist 18 4.5+ 24 Boring Terminated at 191W TEST BORING LOG PLATE B-I Southern California Geotechnical Nr BORING NO. B-2 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS DESCRIPTION SURFACE ELEVATION: MSL LABORATORY RESULTS () z EU 0 0 p EU EU U- a- o - W a- U) - Z 0 Q . - . o a-b z EU o.2 US w 0OQO o =i ., a-i - a-* WZU) WU- Cc Oc OW U) - SANTIAGO FORMATION BEDROCK: Light Gray Brown Silty 59 fine Sandstone, trace Iron oxide staining, very dense-damp to moist 14 Disturbed Sample 60 105 18 56 . 113 13 61 111 15 52 109 19 10- SANTIAGO FORMATION BEDROCK: Gray Green fine Sandy Claystone, dense-moist 27 1.75 26 -5- Boring Terminated at 15' - TEST BORING LOG PLATE B-2 Southern California Geotechnical BORING NO. B-3 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 18 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS (9 DESCRIPTION SURFACE ELEVATION: -- MSL LABORATORY RESULTS 8 P . - . 8 W Zo FILL: Mottled Light Gray to Gray Brown fine Sandy Clay, very 16 3.0 stiff-moist to very moist 97 26 - H - 19 4.5+ 100 20 FILL: Brown fine Sandy Clay, Iron oxide yellow staining, stiff-moist - 5 26 99 21 FILL: Mottled Brown to Light Gray fine Sandy Clay, stiff-moist - 38 No Sample Recovered - 20 101 16 ::. ELLL. Light Gray Brown to Brown Silty fine Sand, medium dense-damp to moist - 10- 26 19 15 19 :: 17 Boring Terminated at 191N -20- - - - TEST BORING LOG PLATE B-3 Southern California Geotechnical I, BORING NO. B-4 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 18 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS -j DESCRIPTION LABORATORY RESULTS w w w to I - W -J a. I— w y o - i a. ., w a. Ui <jO 0 05 2 U) (r:o O O :3 5 06 08 <N 0 ZI 0 - U) - - a. . c SURFACE ELEVATION: -- MSL . o i a. a. 0 - FILL: Gray Brown Clayey fine to medium Sand, loose-damp to moist 15 14 FILL: Mottled Light Gray Brown to Gray Green Clayey fine Sand, trace Iron oxide nodules, medium dense-damp to moist I- 15 18 1 11111 fihL..Mottled Light Gray Brown to Orange I 19 Silt, trace Seashell fragments, dense-moist 21 to 41 13 115 48 15 Boring Terminated at 19'/2' TEST BORING LOG PLATE B-4 15 Southern California Geotechnical BORING NO. B-5 JOB NO.: 06G174-1 DRILLING DATE: 513106 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 12.5 feet LOCATION: Carlsbad California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS DESCRIPTION SURFACE ELEVATION: MSL LABORATORY RESULTS co S - - - W . . CO) 8 Cn co FILL: Brown Clayey fine Sand, medium dense-damp to moist 11 19 14 : 14 - 15 17 j 48 12 - " SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, dense-damp to moist x 10 Nq Boring Terminated at 15 TEST BORING LOG PLATE B-5 Southern California Geotechnical __•%. BORING NO. B-6 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 8 I c DESCRIPTION SURFACE ELEVATION: --- MSL LABORATORY RESULTS U) z 0 0 W W 0 W < Cl) - 0 i — 0 o. — >- o O IL o O 5 o :ii W O..1 WU. Z U) Zc < 0ow ZI DU) 10- 16 20 13 56 6/1 11 50/3" 45---- fiLight Gray Brown Clayey fine to medium Sand, abundant Iron oxide staining, medium dense-damp to moist 120 107 102 132 112 13 14 18 12 12 7 FILL: Brown Clayey fine to medium Sand, some calcareous nodules, some Iron oxide staining, medium dense-damp to moist SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, trace calcareous veining, trace Iron oxide staining, dense-damp to moist N Boring Terminated at 15' TEST BORING LOG . PLATE B-6 Southern California Geotechnical '4W - BORING NO. B-7 JOB NO.: 06G174-1 DRILLING DATE: 513106 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 0 DESCRIPTION LABORATORY RESULTS Cl) p W W Z U) .- w 0 c.) - z w - a- 2- 00 a. a 0 02 w < -J SURFACE ELEVATION: -- MSL 00 o 0 0 fl.L.Orange Brown fine to medium Sandy Clay, abundant calcareous nodules, very stiff-damp to moist 24 22 EI=71@0t05' 27 14 SANTIAGO FORMATION BEDROCK: Light Gray Green Silty 54 fine Sandstone, very dense-damp to moist 12 x 66 13 10- - SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, medium dense-damp to moist 25 19 Boring Terminated at 15' TEST BORING LOG PLATE B-7 Southern California Geotechnical BORING NO. B-8 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 8 DESCRIPTION LABORATORY RESULTS co W W Z a. RR w WU. W 0 Z z W L ° < ro 06 uJ - jO - SURFACE ELEVATION: --- MSL o.2 o M =i a.:3V.505 1 C.) - SANTIAGO FORMATION BEDROCK: Gray to Green Silty - _______ Claystone, abundant Iron oxide staining, trace to some x 28 3.5 calcareous nodules and veining, very stiff-moist to very moist 23 24 4.5+ 19 x 5 — SANTIAGO FORMATION BEDROCK: Light Gray Silty fine 29 Sandstone, medium dense to dense-moist 17 45 15 10- 36 . 15 15- - Boring Terminated at 15' TEST BORING LOG PLATE B-8 Southern California Geotechnical BORING NO. B-9 JOB NO.: 066174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 0 DESCRIPTION SURFACE ELEVATION: --- MSL LABORATORY RESULTS S -z a. . 8 UL 5 10 c-.. , SANTIAGO FORMATION BEDROCK: Red Brown fine to - 21 medium Sandstone, some Clay to Gray fine Sandy Clay, medium dense to stiff-moist 100 20 - 30 4.5+ 89 32 ? SANTIAGO FORMATION BEDROCK: Gray fine Sandy Claystone, Yellow staining, stiff-very moist 5 42 109 21 SANTIAGO FORMATION BEDROCK: Light Gray Brown fine to medium Sandstone, dense-moist - 59 / 109 19 - SANTIAGO FORMATION BEDROCK: Gray Green fine to N 8/11 > / Sandy Siltstone, trace Clay, dense-damp to moist 113 17 10-- / SANTIAGO FORMATION BEDROCK: Gray Green fine Sandy > Siltstone, some Clay, Iron oxide staining, dense-damp to moist 41 16 15 52 18 SANTIAGO FORMATION BEDROCK: Gray fine Sandy - .Siltstone, trace Clay, very dense-damp to moist Boring Terminated at 19%' TEST BORING LOG PLATE B-9 Southern California Geotechnical BORING NO. B-b JOB NO.: 06G174-1 DRILLING DATE: 513106 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 0 DESCRIPTION LABORATORY RESULTS U) p W uJ Z W U) ZU) W 0 C.) Z W 0 z W ' 0. °- 00 °- a 0 5 O U' 4U — < (I) — -J U' O o. SURFACE ELEVATION: --- MSL . 00 o o o. DU 0 C.) - - SANTIAGO FORMATION BEDROCK: Light Yellow Gray fine Sandy Claystone, slight Iron oxide staining, hard-damp to 61 4.5+ moist 110 19 El = 55 @ 0 to 5' 82 4.5+ 111 16 73/9" 2.75 107 13 9/11 4.5+ 109 19 SANTIAGO FORMATION BEDROCK: Light Gray Silty, fine 3/11' Sandstone, abundant Iron oxide staining, dense to very 116 15 10- dense-moist - x 74 12 Boring Terminated at 15' TEST BORING LOG PLATE B-10 Southern California Geotechnical " - BORING NO. B-Il JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 13 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS 0. o . SURFACE ELEVATION: -- MSL W DESCRIPTION LABORATORY RESULTS Ui o 0 p Ui Ui C C/) Z 0 - -. ob Ui 0 Ui -. ö co o o 0 W — zz < ot zi - SANTIAGO FORMATION BEDROCK: Light Gray Silty fine 38 Sandstone, slight Iron oxide staining, dense-damp to moist 12 41 16 5 ,- 37 15 X 47 16 - SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, abundant Iron oxide staining, dense-damp to moist 10- - 45- 37 - - 19 - Boring Terminated at 15' TEST BORING LOG PLATE B-Il Southern California Geotechnical —. M. BORING NO. B-12 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: 18.5 feet LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS DESCRIPTION SURFACE ELEVATION: --- MSL Wz LABORATORY RESULTS Z Ui 0 o W a. Ui W <jO O_ o Q o. . a:°Ooo o C) o w at zU) o 10- 15 64 75/9" 57 38 55 N60 SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, abundant Iron oxide staining, dense to very dense-damp to moist 113 114 14 15 4 13 15 20 Disturbed Sample No Sample Recovered SANTIAGO FORMATION BEDROCK: Light Yellow Gray Silty fine Sandstone, some Iron oxide staining, dense to very dense-moist - -Boring Terminated at 19W TEST BORING LOG PLATE B-12 Southern California Geotechnical Li. BORING NO. B-13 JOB NO.: 06G174-1 DRILLING DATE: 5/3/06 WATER DEPTH: Dry PROJECT: Bressi Ranch Lots 17-22, PA 3 DRILLING METHOD: Hollow Stem Auger CAVE DEPTH: LOCATION: Carlsbad, California LOGGED BY: Joaquin Baca READING TAKEN: At Completion FIELD RESULTS DESCRIPTION LABORATORY RESULTS W co W W C) CL . Z 55 FA Zc z Ui 2 w < o 9 >-C, U2 z 00 51— O COI- c 06 z 0 - co - - o. — SURFACE ELEVATION: --- MSL o. o o o u C) SANTIAGO FORMATION BEDROCK: Light Gray Silty fine Sandstone, abundant Iron oxide staining, dense-damp to 37 moist 15 35 15 5-0 42 16 38 0 18 10 22 25 15 Boring Terminated at 15' TEST BORING LOG PLATE B-13 APPENDIX C LABORATORY TESTING APPENDIX 0 GRADING GUIDE SPECIFICATIONS I Grading Guide Specifications Page 1 GRADING GUIDE SPECIFICATIONS These grading guide specifications are Intended to provide typical procedures for grading operations. They are intended to supplement the recommendations contained In the geotechnical investigation report for this project. Should the recommendations in the geotechnical investigation report conflict with the grading guide specifications, the more site specific recommendations In the geotechnical investigation report will govern. General The Earthwork Contractor Is responsible for the satisfactory completion of all earthwork in accordance with the plans and geotechnical reports, and In accordance with city, county, and Uniform Building Codes. The Geotechnical Engineer is the representative of the Owner/Builder for the purpose of Implementing the report recommendations and guidelines. These duties are not Intended to relieve the Earthwork Contractor of any responsibility to perform In a workman-like manner, nor Is the Geotechnical Engineer to direct the grading equipment or personnel employed by the Contractor. The Earthwork Contractor is required to notify the Geotechnical Engineer of the anticipated work and schedule so that testing and Inspections can be provided. If necessary, work may be stopped and redone if personnel have not been scheduled in advance. The Earthwork Contractor is required to have suitable and sufficient equipment on the job- site to process, moisture condition, mix and compact the amount of fill being placed to the specified compaction. in addition, suitable support equipment should be available to conform with recommendations and guidelines in this report. Canyon cleanouts, overexcavation areas, processed ground to receive fill, key excavations, subdrains and benches Should be observed by the Geotechnical Engineer prior to placement of any fill. It Is the Earthwork Contractors responsibility to notify the Geotechnical Engineer of areas that are ready for inspection. Excavation, filling, and subgrade preparation should be performed in a manner and sequence that will provide drainage at all times and proper control of erosion. Precipitation, springs, and seepage water encountered shall be pumped or drained to provide a suitable working surface. The Geotechnlcal Engineer must be informed of springs or water seepage encountered during grading or foundation construction for possible revision to the recommended construction procedures and/or installation of subdrains. Site PreDaratlon The Earthwork Contractor is responsible for all clearing, grubbing, stripping and site preparation for the project in accordance with the recommendations of the Geotechnical Engineer. If any materials or areas are encountered by the Earthwork Contractor which are suspected of having toxic or environmentally sensitive contamination, the Geotechnical Engineer and Owner/Builder Should be notified immediately. Major vegetation should be stripped and disposed of off-site. This includes trees, brush, heavy grasses and any materials considered unsuitable by the Geotechnical Engineer. Grading Guide Specifications Page 2 Underground structures such as basements, cesspools or septic disposal systems, mining shafts, tunnels, wells and pipelines should be removed under the inspection of the Geotechnical Engineer and recommendations provided by the Geotechnical Engineer and/or city, county or state agencies. if such structures are known or found, the Geotechnical Engineer should be notified as soon as possible so that recommendations can be formulated. Any topsoil, siopewash, coliuvium, alluvium and rock materials which are considered unsuitable by the Geotechnical Engineer should be removed prior to fill placement. RemaIning voids created during site clearing caused by removal of trees, foundations basements, irrigation facilities, etc., should be excavated and filled with compacted fill. Subsequent to clearing and removals, areas to receive fill should be scarified to a depth of 10 to 12 inches, moisture conditioned and compacted The moisture condition of the processed ground should be at or slightly above the optimum moisture content as determined by the Geotechnical Engineer. Depending upon field conditions, this may require air drying or watering together with mixing and/or discing. Compacted Fills Soil materials imported to or excavated on the property may be utilized in the fill, provided each material has been determined to be suitable in the opinion of the Geotechnical Engineer. Unless otherwise approved by the Geotechnical Engineer, all fill materials shall be free of deleterious, organic, or frozen matter, shall contain no chemicals that may result in the material being classified as contaminated, and shall be low to non-expansive with a maximum expansion index (El) of 50. The top 12 inches of the compacted fill should have a maximum particle size of 3 inches, and all underlying compacted fill material a maximum 6- inch particle size, except as noted below. AM soils should be evaluated and tested by the Geotechnical Engineer. Materials with high expansion potential, low strength, poor gradation or containing organic materials may require removal from the site or selective placement and/or mixing to the satisfaction of the Geotechnical Engineer. Rock fragments or rocks greater than 6 inches should be taken off-site or placed in accordance with recommendations and in areas designated as suitable by the Geotechnical Engineer. Acceptable methods typically Include windrows. Oversize materials should not be placed within the range of excavation for foundations, utilities, or pools to facilitate excavations. Rock placement should be kept away from slopes (minimum distance: 15 feet) to facilitate compaction near the slope. Fill materials approved by the Geotechnical Engineer should be placed in areas previously prepared to receive fill and in evenly placed, near horizontal layers at about 6 to inches in loose thickness, or as otherwise determined by the Geotechnical Engineer. Each layer should be moisture conditioned to optimum moisture content, or slightly above, as directed by the Geotechnical Engineer. After proper mixing and/or drying, to evenly distribute the moisture, the layers should be compacted to at least 90 percent of the maximum dry density in compliance with ASTM D-1557 unless otherwise Indicated. Density and moisture content testing should be performed by the Geotechnical Engineer at random Intervals and locations as determined by the Geotechnical Engineer. These tests are intended as an aid to the Earthwork Contractor, so he can evaluate his workmanship, Grading Guide Specifications Page 3 equipment effectiveness and site conditions. The Earthwork Contractor is responsible for compaction as required by the Geotechnical Report(s) and governmental agencies. After compacted fills have been tested and approved by the geotechnical engineer, the contractor should moisture condition the soils as necessary to maintain the compacted moisture content. Compacted fill soils that are allowed to become overly dry or desiccated may require removal and/or scarification, moisture conditioning and replacement. Soils with medium to high expansion indices are especially susceptible to desiccation. Sandy soils that are allowed to dry can also lose density. Fill areas unused for a period of time may require moisture conditioning, processing and recompaction prior to the start of additional filling. The Earthwork Contractor should notify the Geotechnical Engineer of his intent so that an evaluation can be made; Fill placed on ground sloping at a 5-to-1 inclination (horizontal-to-vertical) or steeper should be benched into bedrock or other suitable materials, as directed by the Geotechnlcal Engineer. Typical details of benching are illustrated on Plates (3-2, G-4, and (3-5. Cutlfiil transition lots should have the cut portion overexcavated to a depth of at least 3 feet and rebuilt with fill (see Plate C-I), as determined by the Geotechnical Engineer. All cut lots should be Inspected by the Geotechnical Engineer for fracturing and other bedrock conditions. If necessary, the pads should be overexcavated to a depth of 3 feet and rebuilt with a uniform, more cohesive soil type to Impede moisture penetration. Cut portions of pad areas above buttresses or stabilizations should be overexcavated to a depth-of 3 feet and rebuilt with uniform, more cohesive compacted fill to Impede moisture penetration. Non-structural fill adjacent to structural fill should typically be placed in unison to provide lateral support. Backfill along walls must be placed and compacted with care to ensure that excessive unbalanced lateral pressures do not develop. The type of fill material placed adjacent to below grade wails must be property tested and approved by the Geotechnical Engineer with consideration Of the lateral earth pressure used in the design. Foundations The foundation influence zone is defined as extending one foot horizontally from the outside edge of a footing, and then proceeding downward at a % horizontal to I vertical (0.5:1) Inclination. Where overexcavatlon beneath a footing subgrade is necessary, it should be conducted so as to encompass the entire foundation influence zone, as described above. Compacted fill adjacent to exterior footings should extend at least 12 Inches above foundation bearing grade. Compacted fill within the interior of structures should extend to the floor subgrade elevation. Fill Slopes The placement and compaction of fill described above applies to all fill slopes. Slope compaction should be accomplished by overfilling the slope, adequately compacting the fill In even layers, including the overfilled zone and cutting the slope back to expose the compacted core. Slope compaction may also be achieved by backrolilng the slope adequately every 2 to 4 vertical feet during the filling process as well as requiring the earth moving and compaction equipment to work close to the top of the slope. Upon completion of slope construction, the Grading Guide Specifications Page 4 slope face should be compacted with a sheepsfoot connected to a sideboom and then grid roiled. This method of slope compaction should only be used If approved by the Geotechnical Engineer. Sandy soils lacking Inadequate cohesion maybe unstable for a finished slope condition and therefore should not be placed within 15 horizontal feet of the slope face. All fill slopes should be keyed into bedrock or other suitable material. Fill keys Should be at least 15 feet wide and inclined at 2 percent into the slope. For slopes higher than 30 feet, the fill key width should be equal to one-half the height of the slope (see Plate G-5). All fill keys should be cleared of loose slough material prior to geotechnical inspection and should be approved by the Geotechnical Engineer and governmental agencies prior to filling. The cut portion of fill over cut slopes should be made first and inspected by the Geotechnical Engineer for possible stabIlization requirements. The fill portion should be adequately keyed through all surficlal soilS and into bedrock or suitable material. Soils should be removed from the transition zone between the cut and fill portions (see Plate G-2). Cut Slopes All cut slopes should be inspected by the Geotechnical Engineer to determine the need for stabilization. The Earthwork Contractor should notify the Geotechnical Engineer when slope cutting is In progress at intervals of 10 vertical feet. Failure to notify may result in a delay in recommendations. Cut slopes exposing loose, cohesionless sands should be reported to the Geotechnical Engineer for possible stabilization recommendations. All stabilization excavations should be cleared of loose slough material prior to geotechnical Inspection. Stakes should be provided by the Civil Engineer to verify the location and dimensions of the key. A typical stabilization fill detail is shown on Plate G-5. Stabilization key excavations should be provided with subdrains. Typical subdrain details are shown on Plates G-6. Subdrains Subdrains may be required in canyons and swales where fill placement Is proposed. Typical subdrain details for canyons are shown on Plate G-3. Subdrains should be installed after approval of removals and before filling, as determined by the Soils Engineer. Plastic pipe may be used for subdrains provided It Is Schedule 40 or SDR 35 or equivalent. Pipe should be protected against breakage, typically by placement in a square-cut (backhoe) trench or as recommended by the manufacturer. Filter material for subdrains should conform to CALTRANS Specification 68-1.025 or as approved by the Geotechnical Engineer for the specific site conditions. Clean %-lnch crushed rock maybe used provided it is wrapped In an acceptable filter cloth and approved by the Geotechnical Engineer. Pipe diameters should be 6 inches for runs up to 500 feet and 8 inches for the downstream continuations of longer runs. Four-inch diameter pipe may be used in buttress and stabilization fills. CUT LOT - - 5' MIN. :• Vy 3' MIN. -CQMPAdtEb FILL. .- -r ZOVEREXCAVATE AND ..' ,.•...<....... •.,. RECOMPACT \ / v_ COMPETENT MATERIAL, As APPROVED - BY ThE GEOTECHNCAL ENGINEER CUT/FILL LOT (TRANSITION) 5'MIN. I : • •,...:••.:...:.•_• : •. . ...... 3' MIN. COMPACTED FILL ZOVEREXCAVATE AND -T RECOMPACT DEEPER OVEREXCAVA11ON MAY BE RECOMMENDED BY THE SOIL ENGINEER IN STEEP TRANSITIONS \ COMPETENT MATERIAL, AS APPROVED ______ BY THE GEOTECHNICAL ENGINEER NEW COMPACTED FILL COMPETENT MATERIAL CUT/FILL CONTACT TO BE SHOWN ON AS..8UILr NATURAL GRADE CUT SLOPE CUT SLOPE TO BE CONSTRUCTED PRIOR TO PLACEMENT OF FILL CUTIFILL CONTACT SHOWN ON GRADING PLAN • W MIN. . -.. - - .• .-:--; .-•.A'#• 4'MIN. • ...-r.: I MAXIMUM HEIGHT OF BENCHES . _J... IS 4 FEET OR AS RECOMMENDED BY THE GEOTECHNICAL ENGINEER L MINIMUM 1 TILT BACK OR 2% SLOPE (WHICHEVER IS GREATER) BEDROCK OR APPROVED COMPETENT MATERIAL KEYWAY IN COMPETENT MATERIAL MINIMUM WIDTH OF 15 FEET OR AS RECOMMENDED BY THE GEOTECHNICAL ENGINEER. KEYWAY MAY NOT BE REQUIRED IF FILL SLOPE IS LESS THAN 5 FEET IN HEIGHT AS RECOMMENDED BY THE GEOTECHNICAL ENGINEER. TURALROUNO.\ 1i QMPACTED FILL \/T /4LE4N0UTEXCAVATN 6 ___________• • • 7 -FIRM NATIVE SOIL/BEDROCK •. 24 18- MIN. •. MINUS 1 CRUSHED ROCK COMPLETELY . SURROUNDED BY FILTER FABRiC, OR ______ • •.•. CLASS II PERMEABLE MATERIAL _ _T ;MIN. - 15" MIN. - 6" DIAMETER PERFORATED PIPE - MINIMUM 1% SLOPE PIPE DEPTH OF FILL MATERIAL OVER SLJBDRAIN SCHEMATIC ONLY ADS (CORRUGATED POLETHYLENE) 8 NOT TO SCALE TRANSITE UNDERDRAIN 20 PVC OR ABS: SDR 35 35 SDR2I 100 FINISHED SLOPE FACE NEW COMPACTED FILL OVERFILL REQUIREMENTS PER PLATE NO.4 COMPETENT MATERIAL TOE OF SLOPE SHOWN ON GRADING PLAN PROJECT SLOPE GRADIENT PLACE COMPACTED BACIILL . .. •.' •• :,. :. TO ORIGINAL GRADE IABt MAYJMUM HEIGHT OF BENCHES IS 4 FEET OR AS RECOMMENDED BY THE GEOTECHNICAL ENGINEER IMINIMUM V liLT BACK 2' MINIMUM -J __________________ OR 2% SLOPE KEY DEPTH (WHICHEVER IS GREATER) KEYWAY IN COMPETENT MATERIAL. MINIMUM WIDTH OF 15 FEET OR AS RECOMMENDED BY THE GEOTECHNIAL ENGINEER. KEYWAY MAY NOT BE REQUIRED IF FILL SLOPE IS LESS THAN 51 IN HEIGHT AS RECOMMENDED BY THE GEOTECHNICAL. ENGINEER. NOTE: BENCHING SHALL BE REQUIRED WHEN NATURAL SLOPES ARE EQUAL TO OR STEEPER THAN 5:1 OR WHEN RECOMMENDED BY THE GEOTECHNICAI. ENGINEER. 3' TYPICAL BLANKET FILL IF RECOMMENDED BY THE GEOTECHNICAL. ENGINEER TOP WIDTH OF FILL AS SPECIFIED BY THE GEOTECHNICAL ENGINEER COMPETENT MATERIAL ACCEPTABLE TO THE SOIL ENGINEER COMPACTED FILL FACE OF FINISHED SLOPE ' MINIMUM HEIGHT OF BENCHES IS 4 FEET OR AS RECOMMENDED BY THE GEOTECHNICAL ENGINEER MINIMUM 1' TILT BACK Z MINIMUM 0R2% SLOPE KEY DEPTH KEYWAY WIDTH, AS SPECIFIED (WHICHEVER IS GREATER) BY THE GEOTECHNICAL ENGINEER DESIGN FINISH SLOPE OUTLETS TO BE SPACED AT 100' MAXIMUM INTERVALS. EXTEND 12 INCHES BEYOND FACE OF SLOPE AT TIME OF ROUGH GRADING CONSTRUCTION. BUTTRESS OR SIDEHIU. FILL BLANKET FILL IF RECOMMENDED TH BY THE GEOTECHNICAL ENGINEER 15' PAX. 2' CLEAR FILTER MATERIAL" TO MEET FOLLOWING SPECIFICATION OR APPROVED EQUIVALENT: (CONFORMS TO EMA STD. PLAN 323) SIEVE SIZE PERCENTAGE PASSING .1" 100 314" 90-100 3(8" 40-100 NO.4 25-40 NO.8 18-33 NO. 30 5-15 NO. 50 0-7 NO. 200 0-3 DETAIL "A 4-INCH DIAMETER NON-PERFORATED OUTLET PIPE TO BE LOCATED IN FIELD BY THE SOIL ENGINEER. "GRAVEL" TO MEET FOLLOWING SPECIFICATION OR APPROVED EQUIVALENT: MAXIMUM SIEVE SIZE PERCENTAGE PASSING 11/2" 100 NO.4 50 NO. 200 8 SAND EQUIVALENT a MINIMUM OF 50 OUTLET PIPE TO BE CON- flILTER MATERIAL - MINIMUM OF FIVE NECTED TO SUBDRAJN PIPE I CUBIC FEET PER FOOT OF PIPE. SEE WITH TEE OR ELBOW ABOVE FOR FILTER MATERIAL SPECIFICATION. ALTERNATIVE: IN LIEU OF FILTER MATERIAL I FIVE CUBIC FEET OF GRAVEL I PER FOOT OF PIPE MAY BE ENCASED I IN FILTER FABRIC. SEE ABOVE FOR I GRAVEL SPECIFICATION. I FILTER FABRIC SHALL BE MIRAFI 140 I OR EQUIVALENT. FILTER FABRIC SHALL I BE LAPPED A MINIMUM OF 12 INCHES LON ALL JOINTS. MINIMUM 4-INCH DIAMETER PVC SCH 40 OR ABS CS SDR 35 WITH A CRUSHING STRENGTH OF AT LEAST 1,000 POUNDS, WITH A MINIMUM DETAIL "A" OF 8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE INSTALLED WITH PERFORATIONS ON BOTTOM OF PIPE. PROVIDE CAP AT UPSTREAM END OF PIPE. SLOPE AT 2 PERCENT TO OUTLET PIPE. NOTES: 1. TRENCH FOR OUTLET PIPES TO BE BACKEILLED WITH ON-SITE SOIL "GRAVEL" TO MEET FOLLOWING SPECIFICATION OR APPROVED EQUIVALENT: MAXIMUM SIEVE SIZE PERCENTAGE PASSING 11/2' 100 NO.4 60 NO. 200 8 SAND EQUIVALENT = MINIMUM OF 50 MINIMUM ONE FOOT THICK LAYER OF MINIMUM ONE FOOT WIDE LAYER OF LOW PERMEABLILITY SOIL IF NOT FREE DRAINING MATERIAL COVERED WITH AN IMPERMEABLE SU (LESS THAN 5% PASSING THE #200 SIEVE) / ILTER MATERIAL - MINIMUM OF TWO CUBIC FEET PER FOOT OF PIPE. SEE BELOW FOR FILTER MATERIAL SPECIFICATION. ALTERNATIVE: IN LIEU OF FILTER MATERIAL . . 'TWO CUBIC FEET OF GRAVEL PER FOOT OF PIPE MAY BE ENCASED IN FILTER FABRIC. SEE BELOW FOR GRAVEL SPECIFICATION. FILTER FABRIC SHALL BE MIRAFI 140 OR EQUIVALENT. FILTER FABRIC SHALL BE LAPPED A MINIMUM OF 6 INCHES L.ON ALL JOINTS. MINIMUM 4-INCH DIAMETER PVC SCH 40 OR ABS CLASS SDR 35 WITH A CRUSHING STRENGTH OF AT LEAST 1.000 POUNDS, WITH A MINIMUM OF 8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE INSTALLED WITH PER ON BOTTOM OF PIPE. PROVIDE CAP AT UPSTREAM END OF PIPE. SLOPE AT 2 PERCENT TO OUTLET PIPE. "FILTER MATERIAL" TO MEET FOLLOWING SPECIFICATION OR APPROVED EQUIVALENT: (CONFORMS TO EMA STD. PLAN 323) SIEVE SIZE PERCENTAGE PASSING 1" 100 314 90-100 3/8" 40-100 NO.4 25-40 NO.8 18-33 NO. 30 5-15 NO. 50 0-7 NO. 200 0-3 APPENDIX E UICSE/SCOMPLJTER PROGRAM OUTPUT 2.00 0) 1.75 0 Co 1.50 - 1.25 < 1.00 Cu 0.75 0 o- 0.50 (I) 0.25 0.00 DESIGN RESPONSE SPECTRUM Seismic Zone: 0.4 Soil Profile: SD 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Period Seconds 2.50 2.25 ** ***** * * ******* * * * * * * * U B C S E I S * * * * Version 1.03 * * * COMPUTATION OF 1997 UNIFORM BUILDING CODE SEISMIC DESIGN PARAMETERS JOB NUMBER: 06G174-1 JOB NAME: Bressi Ranch Lot 17 - 22 FAULT-DATA-FILE NAME: CDMGUBCR.DAT SITE COORDINATES: SITE LATITUDE: 33.1286 SITE LONGITUDE: 117.2610 UBC SEISMIC ZONE: 0.4 UBC SOIL PROFILE TYPE: SD NEAREST TYPE A FAULT: NAME: ELSINORE-JULIAN DISTANCE: 36.0 km NEAREST TYPE B FAULT: NAME: ROSE CANYON DISTANCE: 11.7 km NEAREST TYPE C FAULT: NAME: DISTANCE: 99999.0 km SELECTED UBC SEISMIC COEFFICIENTS: Na: 1.0 Nv: 1.0 Ca: 0.44 Cv: 0.64 Ts: 0.582 To: 0.116 DATE: 05-09-2006 *************************** ***************************************** * CAUTION: The digitized data points used to model faults are * * limited in nwnbr and have been digitized from small- * * scale maps (e.g., 1:750,000 scale). Consequently, * * the estimated fault-site-distances may be in error by * * several kilometers. Therefore, it is important that * * the distances be carefully checked for accuracy and * * adjusted as needed, before they are used in design. ******************************************************************** --------------------------- SUMMARY OF FAULT PARAMETERS --------------------------- Page 1 I APPROX.SOURCE I MAX. I SLIP I FAULT ABBREVIATED IDISTANCEI TYPE I NAG. I RATE j TYPE FAULT NAME I (kin) I ======== I(A,B,C)I I ======= (MW) I (mm/yr) I(SS,DS,BT) ROSE CANYON I 11.7 I B ====== I 6.9 I ========= 1.50 I I SS NEWPORT-INGLEWOOD (Offshore) I 15.9 B 6.9 1.50 I SS ELSINORE-JULIAN I 36.0 A 7.1 I 5.00 I SS ELSINORE-TEMECULA I 36.0 B 6.8 I 5.00 SS CORONADO BANK I 36.8 B 7.4 I 3.00 SS ELSINORE-GLEN IVY I 57.8 B I 6.8 I 5.00 I SS EARTHQUAKE VALLEY I 63.5 B 6.5, I 2.00 I ss PALOS VERDES I 65.3 B 7.1 I 3.00 I SS SAN JACINTO-ANZA I 72.8 A 7.2 12.00 I SS SAN JACINTO-SAN JACINTO VALLEY I 75.2 B 6.9 I 12.00 I SS SAN JACINTO-COYOTE CREEK 79.1 B 6.8 I 4.00 I SS NEWPORT-INGLEWOOD (L.A.Basin) I 81.3 B 6.9 I 1.00 I SS CHINO-CENTRAL AVE. (Elsinore) I 81.7 B 6.7 I 1.00 I DS ELSINORE-COYOTE MOUNTAIN I 85.7 B I 6.8 I 4.00 SS ELSINORE-WHITTIER I 87.9 B 6.8 I 2.50 SS SAN JACINTO-SAN BERNARDINO I 98.8 B 6.7 I 12.00 I SS SAN JACINTO - BORREGO ' I 99.7 B 6.6 I 4.00 I SS SAN ANDREAS - Southern I 104.1 A 7.4 24.00 SS PINTO MOUNTAIN 114.9 B 7.0 2.50 SS SAN JOSE I 114.9 B 6.5 I 0.50 I DS CUCANONGA 118.4 A 7.0 I 5.00 I DS SIERRA MADRE (Central) I 119.2 B 7.0 3.00 I DS BURNT MTN. I 122.6 B 6.5 I 0.60 I SS NORTH FRONTAL FAULT ZONE (West) I 125.0 I B 7.0 I 1.00 I DS SUPERSTITION MTN. (San Jacinto) I 125.6 B 6.6 I 5.00 I ss EUREKA PEAK I 127.0 B 6.5 I 0.60 I SS CLEGHORN I 127.4 B 6.5 J 3.00 I ss NORTH FRONTAL FAULT ZONE (East) I 131.3 B 6.7 I 0.50 I DS ELMORE RANCH I 131.4 B I 6.6 I 1.00 I SS SUPERSTITION HILLS (San Jacinto) I 133.1 B I 6.6 I 4.00 I SS SAN ANDREAS - 1857 Rupture 133.8 A 7.8 I 34.00 I SS RAYMOND I 134.7 B I 6.5 I 0.50 I DS CLAMSHELL-SAWPIT I 134.7 B I 6.5 I 0.50 I DS ELSINORE-LAGUNA SALADA 136.0 I B I 7.0 I 3.50 I SS VERDUGO I 139.1 B I 6.7 I 0.50 I DS LANDERS I 139.3 B I 7.3 I 0.60 I SS HOLLYWOOD I 142.4 B I 6.5 I 1.00 I DS HELENDALE - S. LOCKHARDT I 142.8 B I 7.1 0.60 I SS BRAWLEY SEISMIC ZONE I 146.7 B I 6.5 I 25.00 I ss LENWOOD-LOCKHART-OLD WOMAN SPRGS I 148.2 B I 7.3 I 0.60 I SS SANTA MONICA I 150.5 B I 6.6 I 1.00 I DS EMERSON So. - COPPER MTN. I 151.9 B I 6.9 I 0.60 I SS JOHNSON VALLEY (Northern) I 152.4 B I 6.7 I 0.60 I ss MALIBU COAST I 155.2 B I 6.7 I 0.30 I DS IMPERIAL I 159.4 A I 7.0 I 20.00 I ss SIERRA MADRE (San Fernando) I 160.0 I B I 6.7 I 2.00 I DS --------------------------- SUMMARY OF FAULT PARAMETERS --------------------------- Page 2 ------------------------------------------------------------------------------- APPROX.SOURCE I MAX. I SLIP I FAULT ABBREVIATED IDISTANCEP TYPE I MAC. I RATE I TYPE FAULT NAME I (km) I (A.B.C) I (Mw) I (mm/vr) I (S.DSBP) PISGAH-BULLION MTN.-MESQUITE LK SAN GABRIEL ANACAPA-DUME CALICO - HIDALGO SANTA SUSANA HOLSER SIMI-SANTA ROSA OAK RIDGE (Onshore) GRAVEL HILLS - HARPER LAKE SAN CAYETANO BLACKWATER VENTURA - PITAS POINT SANTA YNEZ (East) SANTA CRUZ ISLAND M.RIDGE-ARROYO PARIDA-SANTA ANA RED MOUNTAIN GARLOCK (West) PLEITO THRUST BIG PINE GARLOCK (East) WHITE WOLF SANTA ROSA ISLAND SANTA YNEZ (West) So. SIERRA NEVADA OWL LAKE PANAMINT VALLEY LITTLE LAKE TANK CANYON DEATH VALLEY (South) LOS ALAMOS-W. BASELINE LIONS HEAD DEATH VALLEY (Graben) SAN LUIS RANGE (S. Margin) SAN JUAN CASMALIA (Orcutt Frontal Fault) OWENS VALLEY LOS OSOS HUNTER MTN. - SALINE VALLEY HOSGRI DEATH VALLEY (Northern) INDEPENDENCE RINCONADA BIRCH CREEK SAN ANDREAS (Creeping) WHITE MOUNTAINS DEEP SPRINGS 161.8 B 7.1 I 0.60 I SS 162.8 B 7.0 I :1.00 I SS 164.0 B 7.3 I 3.00 J DS 165.3 B 7.1 I 0.60 SS 175.7 B 6.6 5.00 I DS 184.7 B 6.5 0.40 I DS 192.8 B 6.7 1.00 I DS 193.3 B 6.9 I 4.00 I DS 196.5 B 6.9 I 0.60 I SS 201.7 B 6.8 I 6.00 I DS 212.0 B 6.9 I 0.60 I SS 221.3 B 6.8 I 1.00 I DS 221.4 B 7.0 I 2.00 I ss 230.7 B 6.8 I 1.00 I DS 231.8 B 6.7 I 0.40 I DS 235.4 B 6.8 I 2.00 I DS 236.5 A 7.1 6.00 I SS 242.6 B 6.8 2.00 I DS 248.7 B 6.7 0.80 I SS 250.0 A 7.3 I 7.00 I SS 262.5 B 7.2 2.00 I DS 265.7 B 6.9 I 1.00 I DS 267.4 B 6.9 I 2.00 I SS 274.2 B 7.1 0.10 I DS 277.8 B 6.5 I 2.00 I SS 278.1 B 7.2 I 2.50 I SS 278.3 B 6.7 I 0.70 I SS 279.4 B 6.5 I 1.00 I DS 286.2 B 6.9 I 4.00 I SS 309.9 B 6.8 I 0.70 I DS 327.3 B 6.6 I 0.02 I DS 328.1 B 6.9 I 4.00 I DS 336.8 B 7.0 I 0.20 I DS 337.0 B 7.0 I 1.00 I SS 345.3 B 6.5 I 0.25 I DS 347.1 B 7.6 I 1.50 SS 366.8 B 6.8 I 0.50 I DS 372.7 B 7.0 I 2.50 I ss 373.1 B 7.3 I 2.50 I SS 381.7 I A .1 7.2 I 5.00 I SS 383.0 I B I 6.9 I 0.20 DS 387.5 I B 7.3 I 1.00 SS 439.4 I B 6.5 I 0.70 I DS 443.3 I B 5.0 I 34.00 SS 443.8 I B 7.1 I 1.00 I SS 462.1 I B I 6.6 I 0.80 I DS --------------------------- SUMMARY OF FAULT PARAMETERS --------------------------- Page 3 APPROX.ISOURCE I MAX. I SLIP FAULT ABBREVIATED IDISTANCEI TYPE I MAG. I RATE I TYPE FAULT NAME I (km) I ======== I(A,B,C)I (Mw) I (mm/yr) I(SS,DS,BT) DEATH VALLEY (N. of Cucainongo) I 466.8 I ======= I A ====== I 7.0 I ========= 5.00 I I SS ROUND VALLEY (E. of S.N.Mtns.) 474.7 B 6.8 1.00 I DS FISH SLOUGH I 482.3 B 6.6 I 0.20 I DS HILTON CREEK I 500.8 B 6.7 I 2.50 DS HARTLEY SPRINGS I 525.3 B I 6.6 I 0.50 I DS ORTIGALITA I 527.4 B 6.9 I 1.00 I SS CALAVERAS (So.of Calaveras Res) 533.1 B 6.2 15.00 I Ss MONTEREY BAY - TULARCITOS 536.1 B 7.1 I 0.50 I DS PALO COLORADO - SUR I 537.3 B 7.0 3.00 I ss QUIEN SABE I 546.3 B 6.5 I 1.00 I ss MONO LAKE I 561.3 B 6.6 I 2.50 I DS ZAYANTE-VERGELES I 564.9 B 6.8 I 0.10 I ss SARGENT I 570.2 B 6.8 I 3.00 I SS SAN ANDREAS (1906) I 570.2 A 7.9 I 24.00 I SS ROBINSON CREEK I 592.6 B 6.5 0.50 I DS SAN GREGORIO I 611.5 A 7.3 I 5.00 I SS GREENVILLE I 619.7 B 6.9 I 2.00 I SS MONTE VISTA - SHANNON I 620.3 B 6.5 I 0.40 DS HAYWARD (SE Extension) I 620.3 B 6.5 I 3.00 I SS ANTELOPE VALLEY I 633.0 B 6.7 I 0.80 I DS HAYWARD (Total Length) 640.0 A 7.1 9.00 I SS CALAVERAS (No.of Calaveras Res) 640.0 B 6.8 I 6.00 I Ss GENOA . 658.5 B 6.9 1.00 I DS CONCORD - GREEN VALLEY I 687.6 I B 6.9 I 6.00 I SS RODGERS CREEK I 726.5 A 7.0 I 9.00 SS .1 WEST NAPA I 727.3 B 6.5 I 1.00 I SS POINT REYES I 745.6 B 6.8 I 0.30 I DS HUNTING CREEK - BERRYESSA I 749.6 I B 6.9 I 6.00 I SS MAACANA (South) I 789.1 B 6.9 I 9.00 I SS COLLAYOMI I 805.9 I B I 6.5 I 0.60 I SS BARTLETT SPRINGS. I 809.3 A 7.1 6.00 I SS MAACANA (Central) I 830.8 I A 7.1 I 9.00 I SS MAACANA (North) I 890.2 A I 7.1 J 9.00 I SS ROUND VALLEY (N. S.F.Bay) I 896.2 B I 6.8 I 6.00 I ss BATTLE CREEK I 918.9 B 6.5 I 0.50 I DS LAKE MOUNTAIN I 954.7 B 6.7 I 6.00 I SS GARBERVILLE-BRICELAND I 971.9 B 6.9 I 9.00 I SS MENDOCINO FAULT ZONE I 1028.3 A 7.4 I 35.00 I DS LITTLE SALMON (Onshore) I 1034.7 A 7.0 I 5.00 DS MAD RIVER I 1037.4 B 7.1 0.70 I DS CASCADIA SUBDUCTION ZONE I 1042.1 A 8.3 I 35.00 I DS McKINLEYVILLE I 1047.9 I B 7.0 I 0.60 DS TRINIDAD I 1049.4 B 7.3 I 2.50 I DS FICKLE HILL I 1049.9 B 6.9 I 0.60 I DS TABLE BLUFF I 1055.4 B 7.0 I 0.60 I DS LITTLE SALMON (Offshore) 1068.7 I B I 7.1 I 1.00 I DS --------------------------- SUMMARY OF FAULT PARAMETERS Page 4 I APPROX.ISOURCE I M. I SLIP I FAULT ABBREVIATED IDISTANCEI TYPE I NAG. I RATE I TYPE FAULT NNE I (kin) I (A,B,C) I (MW) I (mm/yr) I (SS,DS,BT) I ======== I ======= I BIG LAGOON - BALD MTN.FLT.ZONE 1 1086.2 I B I ====== I 3 I ========= 0.50 I I PS *******************************************************************************