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HomeMy WebLinkAboutCT 97-24; MAY SUBDIVISION-Park Drive; Update Report and Change of Geotechnical Engineer of Record; 1999-02-12CHRISTIAN WHEELER ENGINEERING February 12,1999 Carlsbad Estates LLC CWE 198.100.2 110 Juniper Street San Diego, California 92101 ATTENTION: Herb Palmtag SUBJECT: UPDATE REPORT AND CHANGE OF GEOTECHNICAL ENGINEER OF RECORD, PROPOSED 14-LOT SUBDIVISION TRACT 97-24, PARK DRIVE, CARLSBAD, CALIFORNIA REFERENCE: 1) Preliminary Soil and Geotechnical Investigation, Proposed 14-Lot Residential Subdivision, by Vinje & Middleton Engineering, Inc., dated July 20,1994 2) Grading Report for May Subdivision, Carlsbad Tract 97-27, by Laret Engineering Company Inc., dated October 28,1998. Gentlemen and Ladies: This letter has been prepared to confirm that Christian Wheeler Engineering will assume the duties of the Geotechnical Engineer of Record for the construction phase of the subject project In addition, it is our opinion that the geotechnical data, recommendations and conclusions contained in the above referenced report are still valid for the grading and development of the subject property. If you have any questions regarding this letter, please do not hesitate to contact this office. This opportunity to be of professional service is sincerely appreciated. Respectfully submitted, CHRISTIAN WHEELER ENGINEERING Charles H. Christian, RGE #00215 cc: (4) Submitted 4925 Mercury Street + San Diego, CA 92111 * 619-496-9760 * FAX 619-496-9758 PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PROPOSED 14-LOT RESIDENTIAL SUBDIVISION 3926 PARK DRIVE CARLSBAD, CALIFORNIA JULY 20, 1994 PREPARED FOR: MR. JIM MAY 3926 PARK DRIVE CARLSBAD, CALIFORNIA 92008 JOB #94-215-P VINJE & MIDDLETON ENQINEERINQ, INC. Job #94-215-P July 20, 1994 Mr. Jim May 3926 Park Drive Carlsbad, California 2450 Vineyard Avenue, #102 Rscondido, California 92029-1229 Phone (760) 743-1214 Fax (760) 739-0343 92008 Preliminary Soil and Geotechnical Investigation for Proposed 14-Lot Residential Subdivision, 3926 Park Drive. Carlsbad, California Pursuant to your request, Vinje & Middleton Engineering, Inc'. has completed the attached investigation of soils and geotechnical conditions at the subject site. The following report summarizes~the results of our field investi- gation, laboratory analyses and conclusions, and provides recommendations for the site development as understood.- From a geotechnical engineering standpoint, it is our opinion 'that the site is suitable for the proposed development provided the recommendations presented in this report are incorporated into the design and construction of the project. The conclusions and recommendations provided in this study are consistent with the site geotechnical conditions and are intended to aid in preparation of final development plans and allow more accurate estimates of development costs. Thank you for choosing Vinje & Middleton Engineering, Inc. If you have any questions concerning this report, please do not hesitate to call us. Reference to our Job #94-215-P will help to expedite our response to your inquiries. We appreciate this opportunity to be of service to you. VINJE & MIDDLETON ENGINEERING, INC. Slph M. Vinje GE #863 f X-- RMV/MS/DM/kmh TABLE OF CONTENTS . Page I. INTRODUCTION 1 II. PROPOSED DEVELOPMENT 1 III. SITE DESCRIPTION 1 IV. FIELD" INVESTIGATION 1 V. FINDINGS , 2 A. Earth Materials - Laboratory Tests ... 2 1. Maximum Dry Density and Optimum Moisture Content 2 2. In-Place Dry Density and Moisture Content 3 3. Direct Shear Test 3 4. Expansion Index Test 3 B. Geotechnical Conditions ... 3 1. Existing Fill. 3 2. Terrace Deposits .4 C. Groundwater 4 D. Structural Geology 4 E. Seismicity 4 F. Geologic Hazards 6 VI. CONCLUSIONS AND RECOMMENDATIONS 6 A. General 6 B. Grading and Earthworks 6 C. Slope Stability 8 D. Drainage 8 E. Foundations and Slab-on-Grade 8 F. Retaining Walls 10 G. Pavements 11 H. Utility Trench Backfills 11 I. Grading and Foundation.Plan Review ... 11 J. Geotechnical Inspections 11 K. Preconstruction Meeting 11 VII. LIMITATIONS > 12 ATTACHMENTS: Plate Test Pit Location Map (including Vicinity Map) 1 Test Trench Logs 2-4 Fault - Epicenter Map 5 (continued) Table of Contents/Page 2 Undercutting Detail 6 Key and Benching Details 7&8 Typical Wall Drainage Detail 9 Appendix A: Specifications for Construction of Controlled Fills and Unified Soil Classification Chart Appendix B: General Site Development Recommendations Appendix C: General Grading Recommendations PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PROPOSED 14-LOT RESIDENTIAL SUBDIVISION 3926 PARK DRIVE CARLSBAD, CALIFORNIA I. INTRODUCTION The study site is located on the southeast .corner of Park Drive and Monroe Street in the City of Carlsbad. The approximate site-loca- tion is shown on the Vicinity Map included with this report as a portion of Plate 1. The site is a 4.67-acre, nearly square, graded parcel presently supporting an active nursery with the .associated greenhouses and supporting areas, a single-family residence, and a garage. • Dimensions and orientations, as well as site surface conditions, are indicated on the Test Trench Location Map 'included herein as Plate 1. The Assessor's Parcel Number is 207-061-07. II. PROPOSED DEVELOPMENT A site development and grading plan was made available to us at the time of our investigation. Based upon the site improvement plan, a 14-lot subdivision and a cul-de-sac road construction are planned at the site. Proposed graded cut and fill slopes are designed for 2:1 gradients with approximately 10 feet maximum vertical height. Total earthworks are estimated to be on the order of 2,400 cubic yards cut and fill grading. The development plan further indicates that the existing residence and garage will remain on Lot 9, but the existing AC driveway will be removed. III. SITE DESCRIPTION The subject site is a graded parcel with level pads. The level pads were constructed by conventional cutting and uncontrolled filling, likely for the expansion of the existing nursery. The earthworks carried out for the nursery expansion were considered non-structural and are not documented. The active nursery occupies the majority of the northwestern portion of the property, while vacant level pads occur to the south and east. IV. FIELD INVESTIGATION Fiel"d study of the subject property consisted of five test trenches excavated with a rubber-tired backhoe. The test pits were logged by our project engineer and backfilled. Representative samples of the earth deposits encountered during our subsurface exposures were VINJEtfMIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTINQ PERC TEST SOIL INVESTIGATIONS QEOTECHN1CAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 2 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 collected at selected intervals and transported to our laboratory for .testing and analyses. The location of the test pits are shown on Plate 1. The detailed logs of the test pits and locations of the samples obtained during .this study are presented on Plates 2, 3, and 4. V. FINDINGS A. Earth Materials - Laboratory Testing: Based upon field observa- tions and visual identifications indicated on the attached logs, there are primarily three soil types,- these soil types are referred to in the following sections as Soil Type 1, 2, and 3. SOIL TYPES Soil Type Soil Description 1 light to dark brown silty fine sand 2 medium brown silty fine. sand 3 tan to light brown silty sand The following tests were performed in support of this study. 1. Maximum Dry Density and Optimum Moisture Content: The maximum dry density and. optimum moisture content of Soil Types 1, 2, and 3 were determined in accordance with ASTM D- 1557-91. The results'are tabulated below. Optimum Soil Maximum Di^y Moisture Location Type Density (psf) Content (%) TP-1 @ 2' 1 127.6 7.6 TP-1 @ T 2 131.4 8.3 TP-1 @ 9' 3 128.0 10 .2 • TP = Test Pit These results may be used during the grading where applicable. VINJEff MIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 3 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 2. In-Place Dry Density and Moisture Content: In-place dry . density and moisture content of representative chunk soil samples were determined using the water displacement method. The test results are presented on the logs at the correspond- ing locations. The percent ratios of the in-place dry density to" the corresponding maximum dry density are also determined and included on the excavation logs. 3. Direct Shear Test: A direct shear test .was performed on representative samples of Soil Type 1 for strength parameters in the lateral load and bearing capacity calculations.. Three specimens of the soil were prepared by molding .them in 2M-inch diameter, 1-inch high rings to 90% of the correspond- ing maximum dry density and optimum moisture content and soaked overnight. The specimens were loaded with normal loads of 1, 2, and 4 KSF respectively and sheared to failure, in an undrained shear. The results are presented below. Wet Angle of Apparent Soil Density Int. Fric. Cohesion Location Type fpcf) ° (degree) c. (psf) . TP-1 @ 2' 1 122 .8 34 0 4. Expansion Index Test: An expansion index test was performed on a representative sample of Soil Type 1 in accordance with the Uniform Building Code Standard Procedure 29-2. The results are presented below. Remolded Saturated Soil Moisture Moisture Expansion Location Type Content f%) Content (%) Index (El) TP-1 @ 2' 1 7.8 13.1 0 B. Geotechnical Conditions: The study property is situated within coastal hillside terrain of northern San Diego County. These areas comprise a narrow belt of Pleistocene sedimentary units formed into wave-cut terrace levels. The following deposits are recognized at the project site: r. Existing Fill (unmapped) - Shallow existing fill deposits on the order of one and one-half to four feet below existing _ grades were encountered in our test pits. Fill deposits are comprised of silty fine to medium sands in a dry and loose condition overall. *- VWJE &MIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 4 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20_^_1994 2. Terrace Deposits - The subject property is underlain by silty fine to coarse sandy terrace deposits exposed beneath the upper fills. The Terrace Deposits as encountered in our test pit excavations are in a loose condition at near surface exposures changing rapidly to a dense and cemented condition with depth". C. Groundwater: Groundwater was. not encountered in our -test pit excavations to the depths explored. D. Structural Geology: During our field investigation, no faults were observed or encountered at the property. Based on our review of the pertinent geologic literature and fault maps of the area, the only nearby faults are short, discontinuous features which do not offset recent deposits. Site terrace deposits expose poorly developed bedding structure which is flat lying. E. Seismicity: As with most areas of California, the San Diego region lies within a seismically active zone; however, coastal areas of the county are characterized by low levels of seismic activity relative to inland areas to the east. During a 40-year period (1934-1974), 37 earthquakes were, recorded in San Diego coastal areas by the California Institute of Technology.. None of the recorded events exceeded a Richter magnitude of 3.7, nor did any of the earthquakes generate more than modest ground shaking or significant damages. Most of the recorded events occurred along various offshore faults which characteristically generate modest earthquakes.. Historically, the most significant earthquake events which affect local areas originate along well known, distant fault zones to the east. Less significant events have been recorded along off-shore faults to the west. The, following list repre- sents the most significant active faults'which typically impact the region. Fault Zone Distance from Site Elsinore Fault 25 miles San Jacinto Fault 47 miles f San Andreas Fault 71 miles Coronado Bank Fault 22 miles VINJE & MIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS (JEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 5 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 The location of significant faults and earthquake events relative to the study site are depicted on a Fault - Epicenter Map attached to this report as Plate 5. More recently, the number of seismic events which affect the region appears to have heightened somewhat. Nearly 40 earth- quakes of magnitude 3.5 or higher have been recorded in coastal regions between January, 1984 and August, 1986. Most.of the earthquakes are thought to have been generated along offshore faults. For the most part, the recorded events remain moderate shocks which typically resulted in low levels of ground shaking to local areas. A notable exception to this pattern was recorded on July 13, 1986. An earthquake of magnitude 5.3 shook North County coastal areas with moderate to locally heavy ground shaking resulting in $700,000 in damages, one death, and injuries to 30 people. The quake occurred along an offshore fault located nearly 30 miles southwest of Oceanside. A second series of notable events shook North County areas with a (maximum) magnitude 7.4 shock in the early morning of June 28, 1992. These quakes originated along related segments of the San Andreas Fault approximately 50 miles to the north. Locally high levels of ground shaking over an extended period .of time resulted; however, significant damages to local structures were not reported. The increase in earthquake frequency in the region remains a subject of speculation among geologists; however, based upon empirical information and the .recorded • seismic history of North County areas, the 1986 and 1992 events are thought to represent the highest levels of ground -shaking which can be expected at the study site as a result of seismic activity. In recent years, the Rose Canyon Fault has received added attention from geologists. The fault is a significant structural feature in metropolitan San Diego which includes a series of parallel breaks trending southward from La Jolla Cove through San Diego Bay toward the Mexican border. Recent trenching along the fault in Rose Canyon^indicates that at that location the fault was last active 6,000 to '9,000 years ago. Thus, the fault is classified as "active" by the State of California which defines faults that evidence displacement in the previous 11,000 years as active. More active faults (listed above) are considered most likely to impact the region during the lifetime of the project. The faultfe are periodically active and capable of generating moderate to locally high levels of ground shaking at the project site. Ground separation as a result of seismic activity is not expected at the property. VttUEtfMIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, Californip 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS QEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION • PAGE 6 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20, 1994 F, Geologic Hazards: Geologic hazards are not presently indicated at the project site. Surrounding slopes do not indicate insta- bility. The most significant geologic hazards at the property will be those associated with ground shaking in the event of a maj or seismic event. Liquefaction or related ground rupture failures are not anticipated, VI. CONCLUSIONS AND RECOMMENDATIONS A. General: The following conclusions and recommendations are based upon exposures developed beneath the site to the depths explored, laboratory testing, engineering analyses of the test results, and our experience in the field of geotechnical engineering. B- Grading and Earthworks: 1. Clearing and grubbing .at the site should be completed as recommended in detail in the attached Appendix C. 'All trees and shrubs not to be used for landscaping should be removed from the site prior to any cutting or filling. All buried structures not designated to remain should be removed. All vegetation and soil designated as "unsuitable" by the project geotechnical consultant should be removed under the consul- tant's observations. The ground surface should be plowed.or scarified to a minimum depth of 12 inches or until, the surface is free from roots, ruts, and hummocks. 2. Site Preparation - (a) Treatment of Surface'Soils and Existing Fills (Removal and Recompaction) - The upper native soils and existing fill which mantle the site are not suitable for the support of structures or fills in their present condi- tion. These soils should be excavated down to firm native materials, moisture conditioned to the required moisture content, and recompacted to a minimum of 90% of the corresponding laboratory maximum dry density. The excavations will be on the order of three to nine feet maximum below the existing grades. Approximate removal depths are shown on the enclosed Test Trench Location Map (Plate 1) for specific areas. . .. f In areas of roadway, parking, and driveway areas, the excavations will be on the order of three feet maximum or to firm native soils, whichever is less, extending — VINJEtfMIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 7 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 outside the edge of the pavement as directed in "the field by the proj ect geotechnical consultant. The depth to firm native materials cannot be accurately predicted and will vary throughout the site. The actual depths will be determined during grading by the project geotechnical consultant. All excavation should be inspected and approved by the geotechnical consultant. (b) Scarification and Processing of Subgrade Materials for Cul-de-Sac and Driveway Areas - After completion of the ground preparations outlined above, the upper 12 inches of the subgrade soils beneath the cul-de-sac and driveway areas should be scarified and recompacted to a minimum of 95% of the corresponding maximum dry density at the required moisture content. The subgrade soils .should be prepared at a time not to exceed more than approximately 72 hours prior to the placement of the base materials in order that the appropriate moisture content is main- tained. The base materials should be compacted to a minimum of 95% of the corresponding maximum dry density at the required moisture content. The base materials should be placed at a time not to exceed more than approximately 72 hours prior to the concrete pouring or paving operation. 3. Cut/Fill Transition Lots - The cut portion of all cut/fill transition lots should be undercut a minimum of three feet or 12 inches below the deep footing in order to provide uniform soil conditions beneath the footings and floor slabs. The undercutting should be completed in general accordance with the attached Undercutting Detail (Plate 6). 4. Compaction and Method of Filling - Compaction and method of filling should be completed as recommended in detail in the attached Appendix A. Fill soils should be thoroughly mixed, moisture conditioned to the required moisture contents, and compacted in thin uniform lifts. In-place density tests will confirm adequate compaction in the fill deposits. Earth deposits used as compacted fill should be inspected and approved by the proj ect geotechnical consultant. Asphalt fragments generated from the existing driveway may be used within the fills under the cul-de-sac as long as fragment sizes do not exceed six inches maximum. — VINJEffMIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 * Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTINg PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 8 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 5. Import Fill Materials - If any import soils are used to com- plete the grading, they should be granular and'non-expansive. The import soils should be inspected and approved by a representative from this office prior to the delivery of the soils to the site. Revised foundation recommendations. may be required based upon the tested properties of the import soils and should be anticipated. C. Slope Stability: 1. Fill Slopes - All graded slopes constructed at 2:1 gradients will be grossly stable with respect to deep-seated and surfi- ,. cial failures. However, in some areas loose sand may be exposed in the slope face which may require remedial grading as directed in the field by the geotechnical consultant. It"•' is recommended that all fill slopes be overbuilt and then cut back to the proposed top of bank if order to achieve the 90% compaction. Slope tests will be . taken to verify the compaction requirement. Slope construction should .be completed in general accordance with the enclosed Key and Benching Details, Plates 7 and 8. D. Drainage: All graded lots should direct surface waters away from the proposed buildings and structures. Water should not be allowed to pond at any location on the lot areas or flow over the graded slopes . E. Foundations and Slab-on-Grade: All grading and construction procedures should be completed in accordance with the recom- mendations provided in Appendixes A, B, and C. A report of certification of controlled fill prepared by the project geotechnical engineer will be necessary prior to the excavation of foundation trenches and slab subgrade preparations. On-site soils are non-expansive sandy deposits. The following footing and slab recommendations are appropriate for non-expansive foundation soils. 1. Continuous spread footings may be used for supporting wood stud bearing walls. Footings should be a minimum of 12 inches wide and 12 inches deep for one and two-story • structures and 15 inches wide and 18 inches deep for two- story structures. Isolated square footings, if considered, . should be at least 18 inches wide and 18 inches deep. Foot- ing minimum required depths are measured from the lowest adjacent ground or finished grade not including the thickness of the sand layer under the slabs. VINJEff MIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 9 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 2. Use two #4 reinforcing bars in all interior and' exterior footings. Place one bar three inches below the top of the footing and one bar three inches above the bottom of ,the footing. Reinforcement for isolated square footings should be designed by the project structural engineer. 3 . All interior slabs must be a minimum of four inches in thick- ness reinforced with #3 reinforcing bars spaced 18 inches on' center each way, placed mid-height in the slab. Use four inches of clean sand (SE 30 or greater) beneath all slabs.. A six-mil plastic moisture barrier is recommended, and if used, must be placed mid-height in the sand. 4. The minimum steel reinforcement provided herein is based'on soil characteristics only and is not intended to be in lieu of reinforcement necessary for structural considerations. 5. Provide contraction joints consisting of ' sawcuts spaced 12 feet on center each way within 72 hours of concrete pour for all interior slabs. The sawcuts must be a minimum of one-half inch in depth and must not exceed three-quarter inch in depth or the reinforcing may be damaged. 6. All exterior slabs (walkways, patios, etc.) must be a minimum of four inches in thickness reinforced with minimum 6x6/10x10 welded wire mesh placed mid-height in the slab. Provide contraction joints consisting of sawcuts spaced six feet on center each way within 72 hours of concrete pour. The depths of the sawcuts should be as described in Item #5 above. 7. An allowable bearing capacity of 1,000 psf may be used for continuous and isolated footings. The allowable soil bear- ing pressure provided herein is for dead plus live loads and may be increased by one-third for wind and seismic loading. The allowable soil bearing pressure provided herein was determined for footings having a minimum width of 12 inches and a minimum depth of 12 inches bel,ow the lowest adjacent ground surface. This value may be "increased per Uniform Building Code for additional depths and widths if needed. 8. Footings located on or adjacent to the top of slopes should be extended to a sufficient depth to provide a minimum horizontal distance of seven feet or one-third of the slope height, whichever is greater (need not exceed 40 feet maximum) between the bottom edge of the footing and face of - slope. The outer edge of all fill slopes experience "down slope creep" which may cause distress to structures. If any structures including buildings, patios, sidewalks, swimming — VINJE ff MIDDLETON ENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTINQ PERC TEST SOIL INVESTIGATIONS (JEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 10 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 pools, spas, etc. are placed within the setback; further recommendations will be required. F. Retaining Walls: 1. Expansive clayey soils should not be used for backfilling of any retaining structure. All retaining structures should be designed by the project structural engineer. Retaining walls should maintain at least a 1:2 (horizontal to vertical) wedge of granular non-expansive soils backfill measured -from the base of the wall footing to the ground surface (within 'the active zone of the wall) . All retaining walls should be provided with a drain along the backside as generally.shown on the attached Typical Wall Drain Design, Plate 9. Specific drainage provisions behind retaining wall structures should be verified by this office. 2. Lateral active pressures for select sandy soils with a minimum friction angle of 34 degrees and assumed drained -and level backfill conditions are provided below. These' values may be used for preliminary design estimates only and are to be re-evaluated when the characteristics of the backfill soils have been determined. Revised recommendations should be anticipated. Passive resistance for on-site soils is also provided. Active Pressure = 35 pcf equivalent fluid pressure, cantilever unrestrained walls. At Rest Pressure = 54 pcf equivalent fluid' pressure, restrained walls. Passive Pressure = 434 pcf equivalent fluid pressure, level ground condition.* *Note: Because large movements m\ist take place before maximum passive resistance can be '"developed, the earth pressures given for passive conditions should be reduced by a safety factor of two. 3. A coefficient of friction of 0.42 may be considered for concrete on soils. This value is to be verified at the completion of grading when the properties of the subgrade soils are specifically known. VINJEffMIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 11 3926 PARK DRIVE. CARLSBAD. CALIFORNIA JULY 20. 1994 G. Pavements: Structural sections for the driveway and parking designs will be determined at the completion of grading with the appropriate sampling and laboratory testing. Pavement.struc- tural section design will depend on R-value test results performed on the subgrade soils and should be given by the project geotechnical consultant. H. Utility Trench Backfill: All underground utility trenches should be compacted to a minimum of 90% of the maximum dry density of the soil unless otherwise specified by the respective agencies. Care should be taken not to crush the utilities or pipes during the compaction of the soil. All utility trenches under slabs.in expansive soils (expansion more than 2%) should be backfilled with sand (S. E. 30 or greater) and properly compacted to achieve at least the minimum compaction requirements. The bottom of all utility trenches should be inspected by the project geotechnical engineer or his representative prior to placement of the utility or backfill operations. I. Grading and Foundation Plan Review: Final grading and founda- tion plans should incorporate recommendations provided in this report and be reviewed and approved by the project geotechnical consultant. If the final development plans significantly change, or if they were not available at the time of this investigation, further investigation and subsoil study may be required and should be anticipated. J. Geotechnical Inspections: The bottom of all excavations associated with removal and recompaction of the upper soils, as well as all keys and benches and utility trenches, should be inspected and approved by the geotechnical consultant. The project geotechnical consultant shouldv also be notified to inspect all footing trenches -and foundation reinforcement prior to placing the steel and pouring of the concrete. K. Preconstruction Meeting: A preconstruction meeting is required prior to grading with the owner, grading contractor, design civil engineer, soils engineer, geologist, city grading inspector, project planner, and representatives of the engineering department. VINJEtfMIDDLETONENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTINQ PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION PAGE 12 3926 PARK DRIVE, CARLSBAD. CALIFORNIA JULY 20. 1994 VII. LIMITATIONS The conclusions and recommendations provided herein have been based on all available data obtained from our field investigation and laboratory analyses, as well as our experience with the soils and formational materials located in the general area. The materials encountered on the project site and utilized in our laboratory testing are believed representative of the total area,- however, earth materials may vary in characteristics between excavations, . Of necessity we must assume a certain degree of continuity between exploratory excavations and/or natural exposures. It is necessary, therefore, that all observations, conclusions, and recommendations . be verified during the grading operation. In the event discre- pancies are noted, we should be'contacted immediately so that an inspection can be made and additional recommendations issued if required. The recommendations made in this report are applicable to the site at the time this report was prepared. It is the responsibility of the owner/developer to insure that these recommendations are carried out in the field. - • It is almost impossible to predict with certainty the future performance of a property. The future behavior of the site is also dependent on numerous unpredictable variables, such as earthquakes, rainfall, and on-site drainage patterns. The firm of VINJE & MIDDLETON ENGINEERING, INC. shall not be held responsible for changes to the physical conditions of the property ' such as * addition of fill soils, added cut slopes, or, changing drainage patterns which occur without our inspection or control. The homeowner should be aware of the development of cracks in concrete surfaces such as floor 'slabs and exterior stucco associated with normal concrete shrinkage during the curing process. These features depend chiefly vupon the condition of concrete and weather conditions at the time Naf construction, and do not reflect detrimental ground movement. Hairline stucco cracks will often develop at window/door corners, and floor surface cracks up to 1/8-inch wide in 20 feet may develop as a result of normal concrete shrinkage (according to the American Concrete Institute). This report should be considered valid for a period of one year and is subject to review by our firm following that time. If significant modifications are made to your tentative development plan, especially with respect to the height and location of cut and fill slopes, this report must be presented to us for review and possible revision. VINJE ff MIDDLETON ENQINEERINQ, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 • Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TEST1NQ PERC TEST SOIL INVESTIGATIONS QEOTECHNICAL INVESTIGATIONS PRELIMINARY SOIL AND GEOTECHNICAL INVESTIGATION 3926 PARK DRIVE. CARLSBAD. CALIFORNIA PAGE 13 JULY 20. 1994 Vinje & Middleton Engineering, Inc. warrants that this report has been prepared within the limits prescribed by our client with the usual thoroughness and competence of the engineering profession. No other warranty or representation, either expressed or implied, is included or intended. Once again, should any questions arise concerning this report, please do not hesitate to contact this office. Reference to our Job #94-215-P will expedite response to your inquiries. We appreciate this opportunity to be of service to'you. VINJE & MIDDLETON ENGINEERING, INC. Ralph M. Vinje- GE #863 Dennis Middleton CEG #980 Mehdi Shariat RCE #46174 RMV/MS/DM/kmh Attachments: Plates 1 througl a:94-215-P d Appendixes A, B, and C VINJEtf MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102, Escondido, California 92029-1229 * Phone (760) 743-1214 • Fax (760) 739-0343 SOIL TESTING PERC TEST SOIL INVESTIGATIONS GEOTECHNICAL INVESTIGATIONS Date 7/7/94 Logged by DM/SMS ua - — — 5 — - - 10 —SAMPLE-QJi \f — I \LJ DB £WL TEST TRENCH 1 DESCRIPTION FILL: Silty fine sand. -Light to dark brown. Slightly moist to dry, friable. SOIL TYPE 1 TERRACE DEPOSIT: Silty fine to medium sand. Medium brown. Porus. Moist, loose. ' SOIL TYPE 2 Sand. Dark brown. Medium grained. Wet, medium dense, grading to friable. SOIL TYPE 2 Silty sand. Tan color. Porus. Moist, friable, dense.MOISTURE(%)2.8 3,2 12.8 11.1 DRYDENSITY(PCF)98.9 106.2 118.4 117.5 RELATIVECOMPACTION(%J77 81 90 92 Date 7/7/94 . Logged by DM/SMS jEp o - - — 10 — LU a.5 a a \, \ TEST TRENCH 2 DESCRIPTION FILL: Silry sand. Light brown grading to dark brown. Dry on surface to moist at depth. Loose. SOIL TYPE 1 TERRACE DEPOSIT: Silty fine sand. Tan color. Porus. Slightly moist. Cemented, dense. ' SOIL TYPE 3 LUo:Z3 ,_ co 5s-o -" 2.6 2.2 >tirtr w o o 111.1 130.1 o i ot- < 87 100+ VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102 Escondido, CA 92029-1229 619/743-1214 TEST TRENCH LOGS JAMES MAY - PARK DRIVE • f— tbulk sample [I chunk sample Project No. 9A-215-P pjate (\]0. 2 Date 7/7/94 Logged by DM/ SMS ira — _ — 5 — - 10 — -SAMPLE\ \ \ TEST TRENCH 3 DESCRIPTION ' FILL: Slightly fine sand. Mottled light to medium brown. Slightly moist, loose. SOIL TYPE 1 TERRACE DEPOSIT: Sand. Fine-grained. Light brown. Friable. Slightly moist. SOIL TYPE 2 Sand. Medium grained. Rusty brown. Slightly moist, loose. SOIL TYPE 2 From 6', color is uniformly dark, grading to medium brown. \ Remains loose. SOIL TYPE 2 Silty sand. Tan color. Moist, cemented. SOIL TYPE 3 1 • end trench at 10'MOISTURE1%)9.0 >-L_ f*+ > -U- *2XQSiO 120.3 oup2o5£ •fiiS# CO — 94 Dote 7/7/94 Logged by DM/SMS a"" _ ... — 5 — — 10 —SAMPLE\ \\ TEST TRENCH 4 DESCRIPTION FILL: Silty fine sand, light to medium brown. Moist to dry, loose, includes rootlets in upper foot. SOIL TYPE 1' TERRACE DEPOSITS: Sand. Medium to coarse grained, medium to dark brown. Moist to wet, loose. SOIL TYPE 2 Silty sand. Tan color. Moist, cemented, dense.v UJ£E o — 10.6 > ^ Qj *^ffa 114.1 zo £ o ** t — a: u — 89 VINJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102 Escondido, CA 92029-1229 619/743-1214 TEST TRENCH LOGS JAMES MAY - PARK DRIVE I j chunk sample Project No. 94-215-P Plate No. 3 Date 7/7/94 Logged by SMS/DM ira - 10 —SAMPLEX ^Ch\ TEST TRENCH 5 DESCRIPTION FILL: Silty fine to medium sand. Light to medium brown. Dry loose. Includes rootlets in upper foot. SOIL TYPE 1 \ TERRACE DEPOSIT: Sand, medium to coarse grained. Medium to dark brown. Moist to dry, loose. SOIL TYPE 2 Silty sand. Tan to light brown. Moist, cemented, dense. SOIL TYPE 3 MOISTURE(%)3.5 •_ tiT *2Xa u£o 131.7 RELATIVECOMPACTION(%}100+ Date Logged by . HPu. o 5. — — 10 — D-2 TEST TRENCH DESCRIPTION ^ UJcc 3 *~ -J3CO J^ 0 ~£ , r~i 2 Q- O Oup£ o a: u — V1NJE & MIDDLETON ENGINEERING, INC. 2450 Vineyard Avenue, #102 Escondido, CA 92029-1229 619/743-1214 TEST TRENCH LOGS JAMES MAY - PARK DRIVE [ [ chunk sample Project No. 9A-215-P Plate No. 4 v \ ' i \ e E\ >r \\ - EPICENTER MAP SAN DIEGO COUNTY REGION INDICATED EARTHQUAKE EVENTS THROUGH 75 YEAR PERIOD (1900-1974) Map data is compiled from various sources including California Division of Mines and Geology, California Institude of Technology and the National Oceanic and Atmospheric Administration. Map is reproduced from California Division of Mines and Geology. "Earthquake Epicenter Map of California; Map Sheet 39." Earthquake' Magnitude . 4.0 TO 4.9 O 5.0 TO 5.9 30 20 10 0 30 MILES 6.0 TO 6.9 7.0 TO 7.9 —_.... Fault Vinje & Middleton ENGINEERING, INC PROJECT 94-215-P PLATE NO. UNDERCUTTING DETAILS (Typical - no scale) existing ground surface compacted fill remove unsuitable materials f-L^-^36" min. 12" min, t utsI _=MMin overexcava.te and recompact competent bedrock or firm native ground per project geotechnical engineer CUT-FILL LOT deepest footing existing ground surface remove unsuitable materials overexcavate and recompact competent bedrock or firm native ground per project geotechnical engineer CUT LOT deepest footing Note: Some agencies require complete removal and recompaction of the entire cut portion of the lot. Also, removal and recompaction of the entire cut portion may be required by the project geotechnical engineer based upon soil and groundwater condition at the site. Vertical and horizontal limits of overexcavation are subject to additional revision by the project geotechnical consultant based upon the actual site conditions. Subdrains may also be necessary as determined by the geotechnical consultant. ' PLATE # 6 KEY AND BENCHING DETAILS (Typical - no scale) finish slope finish pad. existing ground surface remove unsuitaole materials cut slope (to be excavated prior to fill placement) bench competent bedrock or firm native ground per- project geotechnical consultant Fill-Over-Cut Slope existing ground surface finish pad remove unsuitable materialsproject 1:1 line from toe of slope to competent materials 2' min. key depth 15' mm. key width cut slope (to be excavated prior to fill placement) bench per project geotechnical engineer in the field - also, see geotechnical report competent bedrock or firm native ground per project geotechnical consultant Cut-Over-Fill Slope Note: Key and benching details shown herein are subject to revision by the project geotechnical engineer based upon actual site conditions. Back drains may also be necessary as determined by the project geotechnical consultant. Plate #7 KEY AND BENCHING DETAILS (Typical - no scale) project 1:1 line from top of slope to outside edge of kev xunsuitabl materials/^ existing ground. surface finish cut pad I one equipment, width min. i.depth min. width bench competent bedrock, or firm/ native ground per project geotechnical engineer .pad overexcavation and recompaction per project geotechnical engineer I Side Hill Stability Fill Slope existing ground surface finish pad finish slope compacted fill project 1:1 line from toe of slope to competent materials one equipment width minimum remove unsuitable materials 2' min. key depth 15' mm. key width Fill Slope competent bedrock or firm native ground per project geotechnical engineer Note: Key and benching details shown herein are subject to revisions by the project geotechnical engineer based upon actual site conditions Back drains may also be necessary as determined by the project geotechnical consultant. Plate #8 TYPICAL WALL DRAINAGE DESIGN NOTE: SUBJECT TO REVISION BY THE GEOTECHN1CAL CONSULTANT BASED UPON SITE CONDITIONS SOIL BACKFILL COMPACTED TO 90 PERCENT RELATIVE COMPACTION RETAINING WALL WALL WATERPROOFING - — _^ PER ARCHITECT'S SPECIFICATIONS ^.H^ ^ .WALL FUOI INta — - '"' — ••>• - ••' .; • -' '•'. •;- .."-':• '- \l 0 6" MIN. ° 0OVERLAP o °o' ° ; 1' MIN. • Do00! 0 3 O *"' ,. o V-X JC- w° o •?— ^ -r"//-r/i-'tn l^-m = " •*- - — k, 3" MIN FILTER FABRIC ENVELOPE (MIRAF1 140N OR APPROVED EQUIVALENT)-* -COMPACTED FILL 3/4ll-11/2" CLEAN GRAVEL' 4" (MIN.) DIAMETER PERFORATED PVC PIPE (SCHEDULE 40. OR ECUIVALENTJWITH PERFORATIONS ORIENTED DOWN AS DIPICTED MINIMUM 1 PERCENT GRADIENT TO SUITABLE OUTLET SPECIFICATIONS FOR CALTRAHS CLASS 2 PERMEABLE MATERIAL U.S. Standard Sieve Size X Passing 1" 3/4" 3/8" No. 4 No. 8 No. 30 No. 50 • No. 200 100 90-100 40-100 25-40 18-33 5-15 0-7 0-3 Sand Equivalent > 75 COMPETENT BEDROCK OR MATERIAL AS EVALUATED BY THE GEOTECHNICAL CONSULTANT *BASED ON ASTM D1557 ** IF CALTRANS CLASS 2 PERMEABLE MATERIAL . (SEE GRADIENT TO LEFT) IS USED IN PLACE OF 3/4"-1 1/2" GRAVEL, FILTER FABRIC MAY BE DELETED. CALTRANS CLASS 2 PERMEABLE MATERIAL SHOULD BE COMPACTED TO 90 PERCENT RELATIVE COMPACTION- MOT TO SCALE PLATE #9 APPENDIX A 8/88 SPECIFICATIONS FOR CONSTRUCTION OF CONTROLLED FILLS GENERAL DESCRIPTION 1. The following grading specifications have been prepared for the subject site and are consistent with the Preliminary Investigation Report performed by this firm. 2. The grading contractor shall be responsible to perform ground preparation and compaction of fills in strict compliance with the specifications outlined herein. All earthwork including ground preparations, placing, watering, spreading, and compacting of fills should be done under the supervision of a state registered geotechnical engineer. The project geotechnical engineer should be consulted if any deviations from the grading requirements provided herein are desired by the owner/developer. 3. The construction of controlled fills shall consist of clearing and removal of existing structures and foundations, preparation of land to be filled, excavation of earth and rock from cut area, compaction and control of the fill, and all other work necessary to complete the grading of the filled areas to conform with the lines, grades, and slopes as shown on the accepted plans. CLEARING AND PREPARATION OF AREAS TO BE FILLED 1. All fill control projects shall have a preliminary soil investigation or a visual examination (depending upon requirements of the governing agency and the nature of the job) by a qualified geotechnical engineer prior to grading. 2. All timber, trees, brush, vegetation, and other rubbish shall be removed, piled, and burned, or otherwise disposed of to leave the prepared areas with a finished appearance, free from unsightly debris. 3. Any soft, swampy, or otherwise unsuitable areas shall be corrected by drainage or removal of compressible material, or both, to the depths indicated on the plans and as directed by the geotechnical engineer. 4. The natural ground which is determined to be satisfactory for the support of the proposed fill shall then be plowed or scarified to a depth of at least six inches (6") or deeper as specified.by the geotechnical engineer. The surface should be free from ruts, hummocks, ;"or other uneven features which would tend to prevent uniform compaction by the equipment to be used. 5. No fill shall be placed until the prepared native ground has been approved by the geotechnical engineer or his representative on site. 6. Where fills are made on hillsides with slopes greater than 5:1 (horizontal to vertical), horizontal benches shall be cut into firm, undisturbed, natural ground. A minimum two-foot deep keyway, one blade width, should be cut. The geotechnical engineer shall determine the width and frequency of all succeeding benches which will vary with the soil conditions and the steepness of slope. 7. After the natural ground has been prepared it shall be brought to the proper moisture content and compacted to not less than 90% of maximum-density per ASTM D-1557-78. .8. Expansive soils may require special compaction specifications as directed in the preliminary soil investigation by the geotechnical engineer. 9. In order to reduce the potential for differential settlement for structures placed on a transition area of the lot, the cut portion should be undercut a minimum depth of three feet below the proposed pad grade or to a minimum depth of twelve inches below the bottom of the footing, whichever is greater, and replaced as structural fill. The undercut should extend a minimum horizontal distance of ten feet outside the building perimeter. 10. Caution should be used during the grading and trench excavations so that existing adjacent or underground structures/improvements are not distressed by the removals. Appropriate setbacks will be required and should be anticipated. All existing utilities on or in the vicinity of the property should be located prior to any grading or trenching operations. These precautions are the responsibility of the owner/contractor. MV ENGINEERING, INC. will not be held responsible for any damage or distress. MATERIALS The fill soils shall consist of select materials, graded so that at least 40 percent of the material passes^ the #4 sieve. The material may be obtained from the excavation, a borrow pit, or by mixing soils from one or more sources. The materials used shall be free from vegetable matter and other deleterious substances. Oversized rocks greater than two feet in maximum diameter should not be included in fills. Rocks greater than 12 inches (12") in diameter should be properly buried ten feet or more below grade, measured vertically. Rocks should be placed per project geotechnical engineer or his representative to assure filling of all voids with compacted soils. Rocks greater than six inches (6") in diameter should not be allowed within the,upper three feet of all graded pads. Rock fills require a special inspection and testing program under direct supervision of the project geotechnical engineer or his representative. If excessive vegetation, rocks, or soils with unacceptable physical characteristics are encountered these materials shall be disposed of in waste areas designated on the plans or as directed by the geotechnical engineer. No material of a perishable, spongy, or otherwise unstable;nature shall be used in the fills. If soils are encountered during the grading operation which were not reported in the preliminary soil investigation further testing will be required to ascertain their engineering properties. Any special treatment recommended in the preliminary or subsequent soil reports not covered herein shall become an addendum to these specifications. Laboratory tests should be performed on representative soil samples to be used as compacted fills in accordance with appropriate testing procedures specified by ASTM in order to determine maximum dry density and optimum moisture content of the fill soils. PLACING, SPREADING, AND COMPACTION OF FILL MATERIAL 1. The selected fill material shall be placed in layers which shall not exceed six inches (6") when compacted. Each layer shall be spread evenly and shall be thoroughly blade-mixed during the spreading to insure uniformity of material and moisture in each layer. 2. When the moisture content of the fill material is below that specified by the geotechnical engineer water shall be added until the moisture content is near optimum as determined by the geotechnical engineer to assure thorough bonding during the compaction process. This is to take place even if the proper density has been achieved without proper moisture. 3. When the moisture content of the fill material is above that specified by the geotechnical engineer the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is near optimum as determined by the geotechnical engineer. 4. After each layer has been placed, mixed, and spread evenly it shall be thoroughly compacted to not less than the recommended minimum compaction requirements per specified maximum density in accordance with ASTM D-1557-78. Compaction shall be by means of tamping or sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other types of rollers. Rollers shall be of such design that they will be able to compact the fill to the specified density. Rolling each layer shall be continuous over its entire area and the rollers shall make sufficient passes to obtain the desired density. The entire area to be filled shall be compacted to the specified density. 5. Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compacting of the slopes shall be accomplished by backrolling the slopes in increments of three to five feet (31- 5") in elevation gain or by overfilling and cutting back to the design configuration or other methods producing satisfactory results. If the method of achieving the required slope compaction selected by the contractor fails to produce the necessary results, the contractor shall rework or rebuild such slopes until the required degree of compaction is obtained. 6. Field density tests shall be made in accordance with ASTM Method D-1556-82 by the geotechnical engineer for approximately each foot in elevation gain after compaction, but not to exceed two feet (2f) in vertical height between tests. The geotechnical engineer shall be notified to test the. fill at regular intervals. If the tests have not been made after, three feet of compacted fill has been placed, the contractor shall stop work on the fill until tests are made. The location of the tests shall be spaced to give the best possible coverage and shall be taken no farther than 100 feet apart. Tests shall be taken on corner and terrace lots for each two feet (21) in elevation gain. The geotechnical engineer may take additional tests as considered necessary to check on the uniformity of compaction. Where sheepsfoot rollers are used, the test shall be taken in the compacted material below the disturbed surface. No additional layers of fill shall be spread until the field density tests indicate that the specified density has been obtained. 7. The fill operation shall be continued in six-inch (6") compacted layers, as specified above, until the fill has been brought to the finished slopes and grades as shown on-the accepted plans. SUPERVISION Supervision by the geotechnical engineer, or his representative shall be made during the filling and compacting operation in order to verify that the fill was constructed in accordance with the preliminary soil report or agency requirements. The specifications and soil testing of subgrade and basegrade material for roads or other public property shall be done in accordance with specifications of the governing agency unless otherwise directed. It should be understood that the contractor shall supervise and direct the work and shall be responsible for all construction means, methods, techniques, sequences, and procedures. The contractor will be solely and completely responsible for conditions at the j ob site, including safety of all persons and property during the performance of the work. Intermittent or continuous inspection by the geotechnical engineer is not intended to include review of the adequacy of the contractor's safety measures in, on, or near the construction site. SEASONAL LIMITS No fill material shall be placed, spread, or rolled during unfavorable weather conditions. When the work is interrupted by heavy rain, grading shall not be resumed until field tests by the geotechnical engineer indicate that the moisture content and density of the fill are as previously specified. In the event that, in the opinion of the engineer, soils unsatisfactory as foundation material are encountered, they shall not be incorporated in the grading; disposition will be made at the engineer!s discretion. UNIFIED SOIL CLASSIFICATION Identifying Criteria COARSE GRAINED (more than 50% larger than #200 sieve). ; Gravels (more than 50% larger than #4 sieve but smaller than 3"), non-plastic. Symbol Soil Description Sands (more than 50% smaller than #4 sieve), non-plastic. II. FINE GRAINED (more than 50% smaller than #200 sieve). Liquid Limit less than 50. GW GP GM GC SW SP SM SC ML CL Gravel, well-graded gravel- sand mixture, little or no fines. Gravel, poorly graded, gravel-sand mixture, little or no fines. Gravel, silty, poorly graded, gravel-sand-silt mixtures. Gravel, clayey, poorly graded, gravel-sand-clay mixtures. Sand, well-graded, gravelly sands, little or no fines. Sand, poorly graded gravelly sand, little or no fines. Sand, silty, poorly graded, sand-silt mixtures. Sand, clayey, poorly graded, sand-clay mixtures. Silt, inorganic silt and fine sand, sandy silt or clayey-silt-sand mixtures with slight plasticity. Clay, inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays. Unified Soil Classification Page 2 II. FINE GRAINED - continued Liquid Limit greater than 50. OL MH III. HIGHLY ORGANIC SOILS CH OH PT Silt, organic, silts and organic silts-clays of low plasticity. Silt, inorganic silts, micaceous or dictomaceous, fine sand or silty soils, elastic silts. Clay, inorganic, clays of medium to high plasticity, fat clays. Clay, organic clays of medium to high plasticity. Peat, other highly organic swamp soils. APPENDIX B General Site Development Recommendations 1. Finalized development plans should incorporate these recommen- dations and be reviewed and approved by this office; If the finalized development plans significantly change, or if they were not available at the time of this investigation, further investigation and engineering by this firm will be required. • 2. Design in accordance with the latest Uniform Building Code Seismic Zone IV Specifications. Earth shaking during a seismic event should be expected to periodically affect the site and structures. 3. In order to maintain future site performance it is recommended that all pad drainage be collected and directed away from pro- posed structures; a minimum of two percent gradient should be maintained. Roof gutters and downspouts should drain away from the foundations and slabs. Installation of area drains should also be considered. In no case should water be allowed to pond adjacent to structures or flow over slopes. 4. All completed slopes should be planted with appropriate ground cover vegetation to protect the slopes from erosion. Deep- rooted types of ground cover will assist in the prevention of surficial slumping. Excessive watering of the planted slopes should be avoided. An irrigation system should be installed in accordance with the governing agency. 5. Any future structures placed on the subject property may affect the on-site drainage pattern or impact the structural.integrity of the existing fill or structures. Construction of any addi- tional future improvements not included/indicated in the initial development or grading should be reviewed by this firm prior to construction. APPENDIX C General Grading Recommendations 1. Grading operations .on the project should be tested, inspected, and approved by a qualified geotechnical engineer. ' Grading should conform to the codes established by the governing agency. Grading procedures should also be completed in accordance with the enclosed "Specifications for Construction of Controlled Fills", Appendix C, except where superseded below. 2. It. is recommended that a pre-grading meeting be held between the owner, grading contractor, and a representative from this firm to discuss the operation and to arrange a testing schedule. This office should be notified a minimum of 24 hours prior .to any grading or any fill placement. 3. Testing and inspections are required any time fill is placed which exceeds 12 inches in depth under any conditions. .In addition, testing and inspections are required but not limited to the following items: building pads, street improvements, side-walks, curbs and .gutters, undercuts, trench and wall backfills, subgrade and basegrade, foundation trenches and reinforcement, and any other operations not included herein which require our testing, supervision, and inspection for certification to the appropriate agencies. 4. It is recommended that any subsurface structures or other buried objects detected during the. grading be removed. The voids should be filled with compacted soil and tested by the geotech- nical engineer or his representative in. charge. All existing structures which are planned to be removed should be removed prior to grading operations.